WorldWideScience

Sample records for high diversity product

  1. Predicting estuarine benthic production using functional diversity

    Directory of Open Access Journals (Sweden)

    Marina Dolbeth

    2014-05-01

    Full Text Available We considered an estuarine system having naturally low levels of diversity, but attaining considerable high production levels, and being subjected to different sorts of anthropogenic impacts and climate events to investigate the relationship between diversity and secondary production. Functional diversity measures were used to predict benthic production, which is considered as a proxy of the ecosystem provisioning services. To this end, we used a 14-year dataset on benthic invertebrate community production from a seagrass and a sandflat habitat and we adopted a sequential modeling approach, where abiotic, trait community weighted means (CWM and functional diversity indices were tested by generalized linear models (GLM, and their significant variables were then combined to produce a final model. Almost 90% of variance of the benthic production could be predicted by combining the number of locomotion types, the absolute maximum atmospheric temperature (proxy of the heat waves occurrence, the type of habitat and the mean body mass, by order of importance. This result is in agreement with the mass ratio hypothesis, where ecosystem functions/services can be chiefly predicted by the dominant trait in the community, here measured as CWM. The increase of benthic production with the number of locomotion types may be seen as greater possibility of using the resources available in the system. Such greater efficiency would increase production. The other variables were also discussed in line of the previous hypothesis and taking into account the general positive relationship obtained between production and functional diversity indices. Overall, it was concluded that traits representative of wider possibilities of using available resources and higher functional diversity are related with higher benthic production.

  2. Does Labour Diversity affect Firm Productivity?

    DEFF Research Database (Denmark)

    Parrotta, Pierpaolo; Pozzoli, Dario; Pytlikova, Mariola

    Using a matched employer-employee dataset, we analyze how workforce diversity in cultural background, education and demographic characteristics affects productivity of firms in Denmark. Implementing a structural estimation of the firms' production function (Ackerberg et al., 2006) we find...... diverse workforce, seem to outweigh the positive effects coming from creativity and knowledge spillovers....... that labor diversity in education significantly enhances a firm's value added. Conversely, diversity in ethnicity and demographics induces negative effects on firm productivity. Hence, the negative effects, coming from communication and integration costs connected to a more culturally and demographically...

  3. Trade-offs between microbiome diversity and productivity in a stratified microbial mat

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Hans C.; Brislawn, Colin; Renslow, Ryan S.; Dana, Karl; Morton, Beau; Lindemann, Stephen R.; Song, Hyun-Seob; Atci, Erhan; Beyenal, Haluk; Fredrickson, James K.; Jansson, Janet K.; Moran, James J.

    2016-11-01

    Productivity is a major determinant of ecosystem diversity. Microbial ecosystems are the most diverse on the planet yet very few relationships between diversity and productivity have been reported as compared to macro-ecological studies. Here we evaluated the spatial relationships of productivity and microbiome diversity in a laboratory-cultivated photosynthetic mat. The goal was to determine how spatial diversification of microorganisms drives localized carbon and energy acquisition rates. We measured sub-millimeter depth profiles of net primary-productivity and gross oxygenic photosynthesis in the context of the localized microenvironment and community structure and observed negative correlations between species richness and productivity within the energy-replete, photic zone. Variations between localized community structures were associated with distinct taxa as well as environmental profiles describing a continuum of biological niches. Spatial regions corresponding to high primary productivity and photosynthesis rates had relatively low species richness and high evenness. Hence, this system exhibited negative species-productivity and species–energy relationships. These negative relationships may be indicative of photosynthetically-driven, light-controlled mat ecosystems that are able to be the most productive with a relatively smaller, even distributions of species that specialize within the highly-oxic, photic zones.

  4. Soil biota suppress positive plant diversity effects on productivity at high but not low soil fertility

    NARCIS (Netherlands)

    Luo, Shan; Deyn, De Gerlinde B.; Jiang, B.; Yu, Shixiao

    2017-01-01

    Plant community productivity commonly increases with increasing plant diversity, which is explained by complementarity among plant species in resource utilization (complementarity effect), or by selection of particularly productive plant species in diverse plant communities (selection effect).

  5. Composition and diversity of High Andean in the Fauna Production Reserve Chimborazo, Ecuador

    Directory of Open Access Journals (Sweden)

    Jorge Caranqui

    2016-03-01

    Full Text Available The present study inquire the floristic diversity of 9 sampling in four plots of 1 m² of high andean in several locations in the “Reserva de Producción de Fauna Chimborazo”. For the development of this study, we used an adaptation of the method of plots “Gloria”. With coverage (% in each of the plots, Further the diversity indices and similarity with respective analysis were obtained. The data obtained reflect a diversity that can range from medium to low, believe that this is due to anthropogenic activities that have taken place in these ecosistems. With the presence mostly Calamagrostis intermedia, it could establish that the type of vegetation is herbaceous in high andean is higher percentage; is the species that is almost always present in most types of vegetation of the RPF Chimborazo and high dominance that influences the results of low floristic diversity indices was found in the analysis. As a result the most abundant family Asteraceae is well Poaceae.

  6. High genetic diversity among strains of the unindustrialized lactic acid bacterium Carnobacterium maltaromaticum in dairy products as revealed by multilocus sequence typing.

    Science.gov (United States)

    Rahman, Abdur; Cailliez-Grimal, Catherine; Bontemps, Cyril; Payot, Sophie; Chaillou, Stéphane; Revol-Junelles, Anne-Marie; Borges, Frédéric

    2014-07-01

    Dairy products are colonized with three main classes of lactic acid bacteria (LAB): opportunistic bacteria, traditional starters, and industrial starters. Most of the population structure studies were previously performed with LAB species belonging to these three classes and give interesting knowledge about the population structure of LAB at the stage where they are already industrialized. However, these studies give little information about the population structure of LAB prior their use as an industrial starter. Carnobacterium maltaromaticum is a LAB colonizing diverse environments, including dairy products. Since this bacterium was discovered relatively recently, it is not yet commercialized as an industrial starter, which makes C. maltaromaticum an interesting model for the study of unindustrialized LAB population structure in dairy products. A multilocus sequence typing scheme based on an analysis of fragments of the genes dapE, ddlA, glpQ, ilvE, pyc, pyrE, and leuS was applied to a collection of 47 strains, including 28 strains isolated from dairy products. The scheme allowed detecting 36 sequence types with a discriminatory index of 0.98. The whole population was clustered in four deeply branched lineages, in which the dairy strains were spread. Moreover, the dairy strains could exhibit a high diversity within these lineages, leading to an overall dairy population with a diversity level as high as that of the nondairy population. These results are in agreement with the hypothesis according to which the industrialization of LAB leads to a diversity reduction in dairy products. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Increasing Cropping System Diversity Balances Productivity, Profitability and Environmental Health

    Science.gov (United States)

    Davis, Adam S.; Hill, Jason D.; Chase, Craig A.; Johanns, Ann M.; Liebman, Matt

    2012-01-01

    Balancing productivity, profitability, and environmental health is a key challenge for agricultural sustainability. Most crop production systems in the United States are characterized by low species and management diversity, high use of fossil energy and agrichemicals, and large negative impacts on the environment. We hypothesized that cropping system diversification would promote ecosystem services that would supplement, and eventually displace, synthetic external inputs used to maintain crop productivity. To test this, we conducted a field study from 2003–2011 in Iowa that included three contrasting systems varying in length of crop sequence and inputs. We compared a conventionally managed 2-yr rotation (maize-soybean) that received fertilizers and herbicides at rates comparable to those used on nearby farms with two more diverse cropping systems: a 3-yr rotation (maize-soybean-small grain + red clover) and a 4-yr rotation (maize-soybean-small grain + alfalfa-alfalfa) managed with lower synthetic N fertilizer and herbicide inputs and periodic applications of cattle manure. Grain yields, mass of harvested products, and profit in the more diverse systems were similar to, or greater than, those in the conventional system, despite reductions of agrichemical inputs. Weeds were suppressed effectively in all systems, but freshwater toxicity of the more diverse systems was two orders of magnitude lower than in the conventional system. Results of our study indicate that more diverse cropping systems can use small amounts of synthetic agrichemical inputs as powerful tools with which to tune, rather than drive, agroecosystem performance, while meeting or exceeding the performance of less diverse systems. PMID:23071739

  8. Fermentative hydrogen production by diverse microflora

    International Nuclear Information System (INIS)

    Baghchehsaraee, B.; Nakhla, G.; Karamanev, D.; Margaritis, A.

    2009-01-01

    'Full text': In this study of hydrogen production with activated sludge, a diverse bacterial source has been investigated and compared to microflora from anaerobic digester sludge, which is less diverse. Batch experiments were conducted at mesophilic (37 o C) and thermophilic (55 o C) temperatures. The hydrogen production yields with activated sludge at 37 o C and 55 o C were 0.25 and 0.93 mol H 2 /mol glucose, respectively. The maximum hydrogen production rates with activated sludge in both temperatures were 4.2 mL/h. Anaerobic digester sludge showed higher hydrogen production yields and rates at both mesophilic and thermophilic temperatures. The results of repeated batch experiments with activated sludge showed an increase in the hydrogen production during the consecutive batches. However, hydrogen production was not stable along the repeated batches. The observed instability was due to the formation of lactic acid and ethanol. (author)

  9. Regional Farm Diversity Can Reduce Vulnerability of Food Production to Climate Change

    NARCIS (Netherlands)

    Reidsma, P.; Ewert, F.A.

    2008-01-01

    Food production must adapt in the face of climate change. In Europe, projected vulnerability of food production to climate change is particularly high in Mediterranean regions. Increasing agricultural diversity has been suggested as an adaptation strategy, but empirical evidence is lacking. We

  10. Smokeless tobacco products harbor diverse bacterial microbiota that differ across products and brands.

    Science.gov (United States)

    Smyth, Eoghan M; Kulkarni, Prachi; Claye, Emma; Stanfill, Stephen; Tyx, Robert; Maddox, Cynthia; Mongodin, Emmanuel F; Sapkota, Amy R

    2017-07-01

    Smokeless tobacco products contain numerous chemical compounds, including known human carcinogens. Other smokeless tobacco constituents, including bacteria, may also contribute to adverse health effects among smokeless tobacco users. However, there is a lack of data regarding the microbial constituents of smokeless tobacco. Our goal was to characterize the bacterial microbiota of different smokeless tobacco products and evaluate differences across product types and brands. DNA was extracted from 15 brands of smokeless tobacco products (including dry snuff, moist snuff, snus, and Swedish snus) and 6 handmade products (e.g., toombak) using an enzymatic and mechanical lysis approach. Bacterial community profiling was performed using PCR amplification of the V1-V2 hypervariable region of the 16S rRNA gene, followed by 454 pyrosequencing of the resulting amplicons and sequence analysis using the QIIME package. Total viable counts were also determined to estimate the number of viable bacteria present in each product. Average total viable counts ranged from 0 to 9.35 × 10 7  CFU g -1 . Analysis of the 16S rRNA gene sequences revealed high bacterial diversity across the majority of products tested: dry snuff products where characterized by the highest diversity indices compared to other products. The most dominant bacterial phyla across all products were Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetes. Significant differences in both bacterial community composition and in silico predicted gene content were observed between smokeless tobacco product types and between brands of specific smokeless tobacco products. These data are useful in order to comprehensively address potential health risks associated with the use of smokeless tobacco products.

  11. Racial Diversity and Macroeconomic Productivity across US States and Cities

    OpenAIRE

    Sparber, Chad

    2007-01-01

    The United States is growing increasingly diverse, so it is important that economists understand the macroeconomic consequences of diversity within the US economy. International analyses often argue that heterogeneity reduces macroeconomic productivity by engendering corruption, political instability, and social turmoil. However, other studies claim that diversity improves creative decision making and augments productivity. This paper exploits differences in diversity across regions of the Un...

  12. Different Diversity and Distribution of Archaeal Community in the Aqueous and Oil Phases of Production Fluid From High-Temperature Petroleum Reservoirs

    Directory of Open Access Journals (Sweden)

    Bo Liang

    2018-04-01

    Full Text Available To get a better knowledge on how archaeal communities differ between the oil and aqueous phases and whether environmental factors promote substantial differences on microbial distributions among production wells, we analyzed archaeal communities in oil and aqueous phases from four high-temperature petroleum reservoirs (55–65°C by using 16S rRNA gene based 454 pyrosequencing. Obvious dissimilarity of the archaeal composition between aqueous and oil phases in each independent production wells was observed, especially in production wells with higher water cut, and diversity in the oil phase was much higher than that in the corresponding aqueous phase. Statistical analysis further showed that archaeal communities in oil phases from different petroleum reservoirs tended to be more similar, but those in aqueous phases were the opposite. In the high-temperature ecosystems, temperature as an environmental factor could have significantly affected archaeal distribution, and archaeal diversity raised with the increase of temperature (p < 0.05. Our results suggest that to get a comprehensive understanding of petroleum reservoirs microbial information both in aqueous and oil phases should be taken into consideration. The microscopic habitats of oil phase, technically the dispersed minuscule water droplets in the oil could be a better habitat that containing the indigenous microorganisms.

  13. Forest Productivity and Diversity: Using Ecological Theory and Landscape Models to Guide Sustainable Forest Management

    Energy Technology Data Exchange (ETDEWEB)

    Huston, M.A.

    1998-11-01

    Sustainable forest management requires maintaining or increasing ecosystem productivity, while preserving or restoring natural levels of biodiversity. Application of general concepts from ecological theory, along with use of mechanistic, landscape-based computer models, can contribute to the successful achievement of both of these objectives. Ecological theories based on the energetics and dynamics of populations can be used to predict the general distribution of individual species, the diversity of different types of species, ecosystem process rates and pool sizes, and patterns of spatial and temporal heterogeneity over a broad range of environmental conditions. This approach requires subdivision of total biodiversity into functional types of organisms, primarily because different types of organisms respond very differently to the spatial and temporal variation of environmental conditions on landscapes. The diversity of species of the same functional type (particularly among plants) tends to be highest at relatively low levels of net primary productivity, while the total number of different functional types (particularly among animals) tends to be highest at high levels of productivity (e.g., site index or potential net primary productivity). In general, the diversity of animals at higher trophic levels (e.g., predators) reaches its maximum at much higher levels of productivity than the diversity of lower trophic levels (e.g., plants). This means that a single environment cannot support high diversity of all types of organisms. Within the framework of the general patterns described above, the distributions, population dynamics, and diversity of organisms in specific regions can be predicted more precisely using a combination of computer simulation models and GIS data based on satellite information and ground surveys. Biophysical models that use information on soil properties, climate, and hydrology have been developed to predict how the abundance and spatial

  14. High-technology exports of EEC countries: Persistence and diversity of specialization patterns

    International Nuclear Information System (INIS)

    Papagni, E.

    1992-01-01

    This analysis of the persistence and diversity of specialization patterns in EEC high technology exports is based on a package of products selected from the Eurostat database, COMEXT. High technology goods are considered as an innovative output indicator. A test of hypotheses of hysteresis and diversity of trade patterns at a national level is performed to verify some claims made by the 'evolutionary' theory of innovation and trade. The three-mode principal component analysis carried out confirms the persistence of specialization patterns of each EEC country in high technology exports, and highlights their sharp differences

  15. Effect of Pulp mill sludge on soil characteristics, microbial diversity and vegetal production of Lollium perene

    Energy Technology Data Exchange (ETDEWEB)

    Gallardo, F.; Cea, M.; Diez, M. C.

    2009-07-01

    The Chemical properties of the sludge (High organic matter content, pH, buffer capacity, nitrogen and phosphorous level, and low concentration of trace heavy metals and organic pollutants) suggest that this material may represent a valuable resource as soil amendment, improving soil characteristics, microbial diversity and vegetal production of mill sludge addition to volcanic soil (Andisol) on soil characteristics, microbial diversity and vegetal production of Lollium perenne, in field assays. (Author)

  16. Climate-suitable planting as a strategy for maintaining forest productivity and functional diversity.

    Science.gov (United States)

    Duveneck, Matthew J; Scheller, Robert M

    2015-09-01

    Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000-2100) at a 2-ha cell resolution and five-year time steps within two landscapes in the Great Lakes region (northeastern Minnesota and northern lower Michigan, USA). We compared current climate to low- and high-emission futures. We simulated a low-emission climate future with the Intergovernmental Panel on Climate Change (IPCC) 2007 B1 emission scenario and the Parallel Climate Model Global Circulation Model (GCM). We simulated a high-emission climate future with the IPCC A1FI emission scenario and the Geophysical Fluid Dynamics Laboratory (GFDL) GCM. We compared current forest management practices (business-as-usual) to CSP management. In the CSP scenario, we simulated a target planting of 5.28% and 4.97% of forested area per five-year time step in the Minnesota and Michigan landscapes, respectively. We found that simulated CSP species successfully established in both landscapes under all climate scenarios. The presence of CSP species generally increased simulated aboveground biomass. Species diversity increased due to CSP; however, the effect on functional diversity was variable. Because the planted species were functionally similar to many native species, CSP did not result in a consistent increase nor decrease in functional diversity. These results provide an assessment of the potential efficacy and limitations of CSP management. These results have

  17. Small diversity effects on ocean primary production under environmental change in a diversity-resolving ocean ecosystem model

    DEFF Research Database (Denmark)

    Prowe, Friederike; Pahlow, M.; Dutkiewicz, S.

    2013-01-01

    Marine ecosystem models used to investigate how global change affects ocean ecosystems and their functioning typically omit pelagic diversity. Diversity, however, can affect functions such as primary production and their sensitivity to environmental changes. Using a global ocean ecosystem model...... the diversity effects on ecosystem functioning captured in ocean ecosystem models....

  18. Highly task-related diversity vs. less task-related diversity among university staff

    DEFF Research Database (Denmark)

    Lauring, Jakob; Selmer, Jan

    2013-01-01

    from 489 university staff members showed that age diversity and cultural diversity, representing highly task-related diversity, were positively associated with most of the variables depicting group cohesiveness. On the other hand, gender diversity, illustrating less task-related diversity, seemed......As only very few large-scale studies have investigated multi-cultural university staff and as none of these studies have dealt with diversity and group processes, this survey was directed toward staffs in 16 science departments from three large universities in Denmark. Results based on the response...

  19. Diversity and evolution of Lactobacillus casei group isolated from fermented dairy products in Tibet.

    Science.gov (United States)

    Feng, Jing; Jiang, Yujun; Li, Mingyu; Zhao, Siyu; Zhang, Yanming; Li, Xuesong; Wang, Hui; Lin, Guangen; Wang, Hao; Li, Tiejing; Man, Chaoxin

    2018-05-25

    Bacteria in Lactobacillus casei group, including Lactobacillus casei (L. casei), Lactobacillus paracasei (L. paracasei), and Lactobacillus rhamnosus (L. rhamnosus) are important lactic acid bacteria in the production of fermented dairy products and are faced with the controversial nomenclatural status due to their close phylogenetic similarity. To probe the evolution and phylogeny of L. casei group, 100 isolates of lactic acid bacteria originated from naturally fermented dairy products in Tibet of China were subjected to multilocus sequence typing (MLST). The MLST scheme, based on analysis of the housekeeping genes fusA, ileS, lepA, leuS, pyrG, recA and recG, revealed that all the isolates belonged to a group containing the L. paracasei reference strains and were clearly different from the strains of L. casei and L. rhamnosus. Although nucleotide diversity (π) was low for the seven genes (ranging from 0.00341 for fusA to 0.01307 for recG), high genetic diversity represented by 83 sequence types (STs) with a discriminatory index of 0.98 was detected. A network-like structure based on split decomposition analysis, and the high values of the relative effect of recombination and mutation in the diversification of the lineages (r/m = 4.76) and the relative frequency of occurrence of recombination and mutation (ρ/θ = 2.62) indicated that intra-species recombination occurred frequently and homologous recombination played a key role in generating genotypic diversity amongst L. paracasei strains in Tibet. The discovery of 51 new STs and the results of STRUCTURE analysis suggested that the L. casei group in Tibet had an individual and particular population structure in comparison to European isolates. Overall, this research might be the first report about genetic diversity and population structure of Lactobacillus populations isolated from naturally fermented dairy products in Tibet based on MLST scheme.

  20. High genetic diversity of Jatropha curcas assessed by ISSR.

    Science.gov (United States)

    Díaz, B G; Argollo, D M; Franco, M C; Nucci, S M; Siqueira, W J; de Laat, D M; Colombo, C A

    2017-05-31

    Jatropha curcas L. is a highly promising oilseed for sustainable production of biofuels and bio-kerosene due to its high oil content and excellent quality. However, it is a perennial and incipiently domesticated species with none stable cultivar created until now despite genetic breeding programs in progress in several countries. Knowledge of the genetic structure and diversity of the species is a necessary step for breeding programs. The molecular marker can be used as a tool for speed up the process. This study was carried out to assess genetic diversity of a germplasm bank represented by J. curcas accessions from different provenance beside interspecific hybrid and backcrosses generated by IAC breeding programs using inter-simple sequence repeat markers. The molecular study revealed 271 bands of which 98.9% were polymorphic with an average of 22.7 polymorphic bands per primer. Genetic diversity of the germplasm evaluated was slightly higher than other germplasm around the world and ranged from 0.55 to 0.86 with an average of 0.59 (Jaccard index). Cluster analysis (UPGMA) revealed no clear grouping as to the geographical origin of accessions, consistent with genetic structure analysis using the Structure software. For diversity analysis between groups, accessions were divided into eight groups by origin. Nei's genetic distance between groups was 0.14. The results showed the importance of Mexican accessions, congeneric wild species, and interspecific hybrids for conservation and development of new genotypes in breeding programs.

  1. Natural Product Biosynthetic Diversity and Comparative Genomics of the Cyanobacteria.

    Science.gov (United States)

    Dittmann, Elke; Gugger, Muriel; Sivonen, Kaarina; Fewer, David P

    2015-10-01

    Cyanobacteria are an ancient lineage of slow-growing photosynthetic bacteria and a prolific source of natural products with intricate chemical structures and potent biological activities. The bulk of these natural products are known from just a handful of genera. Recent efforts have elucidated the mechanisms underpinning the biosynthesis of a diverse array of natural products from cyanobacteria. Many of the biosynthetic mechanisms are unique to cyanobacteria or rarely described from other organisms. Advances in genome sequence technology have precipitated a deluge of genome sequences for cyanobacteria. This makes it possible to link known natural products to biosynthetic gene clusters but also accelerates the discovery of new natural products through genome mining. These studies demonstrate that cyanobacteria encode a huge variety of cryptic gene clusters for the production of natural products, and the known chemical diversity is likely to be just a fraction of the true biosynthetic capabilities of this fascinating and ancient group of organisms. Copyright © 2015. Published by Elsevier Ltd.

  2. Molds contamination of raw milk and dairy products: Occurrence, diversity and contamination source

    Directory of Open Access Journals (Sweden)

    T Moshtaghi Maleki

    2015-11-01

    Full Text Available This study aimed to assess the occurrence and diversity of mold species in raw milk and its products along with the identification of potential contamination sources. For this reason, a total of 260 samples consisting of 80 raw milk, 100 dairy products (i.e., pasteurized milk, yoghurt, cheese and buttermilk and 80 environmental (i.e. ingredients, packaging materials, surface of processing equipments and air specimens were collected. Using culture assay and microscopic observation, the occurrence as well as the diversity of mold species was investigated. According to the results, 82.3% of the samples were identified as positive for mold contamination. The percentage of mold contamination for raw milk was estimated as 97.5%. In the case of pasteurized milk, yoghurt, buttermilk, cheese and environmental samples, it was determined as 52%, 76%, 52%, 56% and 96.25%, respectively. Mold diversity among various samples consisted of Aspergillus, Geotrichum, Penicillium, Mucor, Alternaria, Rhizopus, Stemphylium, Cladosporium, and Fusarium. Results revealed a significant (p < 0.01 correlation between kind of mold species isolated from raw milk and dairy products. Similarly, a correlation was observed between dairy products and environmental sources. Regarding the high occurrence of mold contamination in raw milk and environmental sources, it seems that in some instances heat treatment was not effective enough to inactivate all molds; whereas in some other cases, cross contamination may have resulted in mold contamination. Therefore, it is crucial to maintain hygienic conditions during raw milk handling as well as processing steps. These practices could efficiently reduce the occurrence of mold contaminations in dairy products.

  3. Primary and heterotrophic productivity relate to multikingdom diversity in a hypersaline mat

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Hans C.; Brislawn, Colin J.; Dana, Karl; Flores-Wentz, Tobias; Cory, Alexandra B.; Fansler, Sarah J.; Fredrickson, James K.; Moran, James J.

    2017-10-01

    Benthic microbial ecosystems are widespread yet knowledge gaps still remain on the relationships between the diversity of species across kingdoms and productivity. Here, we ask two fundamental questions: 1) How does species diversity relate to the rates of primary and heterotrophic productivity? 2) How do diel variations in light-energy inputs influence productivity and microbiome diversity? To answer these questions, microbial mats from a magnesium sulfate hypersaline Lake were used to establish microcosms. Both the number and relatedness between bacterial and eukaryotic taxa in the microbiome were assayed via amplicon based sequencing of 16S and 18S rRNA genes over two diel cycles. These results correlated with biomass productivity obtained from substrate-specific 13C stable isotope incorporation that enabled comparisons between primary and heterotrophic productivity. Both bacterial and eukaryotic species richness and evenness were related only to the rates of 13C labeled glucose and acetate biomass incorporation. Interestingly, measures of these heterotrophic relationships changed from positive and negative correlations depending on carbon derived from glucose and acetate, respectively. Bacterial and eukaryotic diversity of this ecosystem is also controlled, in part, energy constraints imposed by changing irradiance over a diel cycle.

  4. Conservation value of low-productivity forests measured as the amount and diversity of dead wood and saproxylic beetles.

    Science.gov (United States)

    Hämäläinen, Aino; Strengbom, Joachim; Ranius, Thomas

    2018-06-01

    In many managed landscapes, low-productivity land comprises most of the remaining relatively untouched areas, and is often over-represented within protected areas. The relationship between the productivity and conservational value of a site is poorly known; however, it has been hypothesized that biodiversity increases with productivity due to higher resource abundance or heterogeneity, and that the species communities of low-productivity land are a nested subset of communities from more productive land. We tested these hypotheses for dead-wood-dependent beetles by comparing their species richness and composition, as well as the amount and diversity of dead wood, between low-productivity (potential forest growth dead wood, but volume appeared to be a better predictor than diversity for the higher species richness in set-asides. Beetle species composition was similar among stand types, and the assemblages in low-productivity stands were largely subsets of those in high-productivity set-asides. However, 11% of all species and 40% of red-listed species only occurred in high-productivity stands, while no species were unique to low-productivity stands. We conclude that low-productivity forests are less valuable for conservation than high-productivity forest land. Given the generally similar species composition among stand types, a comparable conservational effect could be obtained by setting aside a larger area of low-productivity forest in comparison to the high-productivity. In terms of dead wood volumes, 1.8-3.6 ha of low-productivity forest has the same value as 1 ha of unmanaged high-productivity forest. This figure can be used to estimate the conservation value of low-productivity forests; however, as high-productivity forests harbored some unique species, they are not completely exchangeable. © 2018 The Authors. Ecological Applications published by Wiley Periodicals, Inc. on behalf of Ecological Society of America.

  5. Diverse urban plantings managed with sufficient resource availability can increase plant productivity and arthropod diversity

    Directory of Open Access Journals (Sweden)

    Jonathon eMuller

    2014-10-01

    Full Text Available Buildings structures and surfaces are explicitly being used to grow plants, and these ‘urban plantings’ are typically designed for aesthetic value. Urban plantings also have the potential to contribute significant ‘ecological values’ by increasing urban habitat for animals such as arthropods and by increasing plant productivity. In this study, we evaluated how the provision of these additional ecological values is affected by plant species richness; the availability of essential resources for plants, such as water, light, space; and soil characteristics. We sampled 33 plantings located on the exterior of three buildings in the urban centre of Brisbane, Australia (subtropical climatic region over two, six week sampling periods characterised by different temperature and rainfall conditions. Plant cover was estimated as a surrogate for productivity as destructive sampling of biomass was not possible. We measured weekly light levels (photosynthetically active radiation, plant CO2 assimilation, soil CO2 efflux, and arthropod diversity.Differences in plant cover were best explained by a three-way interaction of plant species richness, management water regime and sampling period. As the richness of plant species increased in a planter, productivity and total arthropod richness also increased significantly - likely due to greater habitat heterogeneity and quality. Overall we found urban plantings can provide additional ecological values if essential resources are maintained within a planter such as water, light and soil temperature. Diverse urban plantings that are managed with these principles in mind can contribute to the attraction of diverse arthropod communities, and lead to increased plant productivity within a dense urban context.

  6. Professional diversity and the productivity of cities.

    Science.gov (United States)

    Bettencourt, Luís M A; Samaniego, Horacio; Youn, Hyejin

    2014-06-23

    Attempts to understand the relationship between diversity, productivity and scale have remained limited due to the scheme-dependent nature of the taxonomies describing complex systems. We analyze the diversity of US metropolitan areas in terms of profession diversity and employment to show how this frequency distribution takes a universal scale-invariant form, common to all cities, in the limit of infinite resolution of occupational taxonomies. We show that this limit is obtained under general conditions that follow from the analysis of the variation of the occupational frequency across taxonomies at different resolutions in a way analogous to finite-size scaling in statistical physical systems. We propose a theoretical framework that derives the form and parameters of the limiting distribution of professions based on the appearance, in urban social networks, of new occupations as the result of specialization and coordination of labor. By deriving classification scheme-independent measures of functional diversity and modeling cities as social networks embedded in infrastructural space, these results show how standard economic arguments of division and coordination of labor can be articulated in detail in cities and provide a microscopic basis for explaining increasing returns to population scale observed at the level of entire metropolitan areas.

  7. Bee species diversity enhances productivity and stability in a perennial crop.

    Directory of Open Access Journals (Sweden)

    Shelley R Rogers

    Full Text Available Wild bees provide important pollination services to agroecoystems, but the mechanisms which underlie their contribution to ecosystem functioning--and, therefore, their importance in maintaining and enhancing these services-remain unclear. We evaluated several mechanisms through which wild bees contribute to crop productivity, the stability of pollinator visitation, and the efficiency of individual pollinators in a highly bee-pollination dependent plant, highbush blueberry. We surveyed the bee community (through transect sampling and pan trapping and measured pollination of both open- and singly-visited flowers. We found that the abundance of managed honey bees, Apis mellifera, and wild-bee richness were equally important in describing resulting open pollination. Wild-bee richness was a better predictor of pollination than wild-bee abundance. We also found evidence suggesting pollinator visitation (and subsequent pollination are stabilized through the differential response of bee taxa to weather (i.e., response diversity. Variation in the individual visit efficiency of A. mellifera and the southeastern blueberry bee, Habropoda laboriosa, a wild specialist, was not associated with changes in the pollinator community. Our findings add to a growing literature that diverse pollinator communities provide more stable and productive ecosystem services.

  8. Bee species diversity enhances productivity and stability in a perennial crop.

    Science.gov (United States)

    Rogers, Shelley R; Tarpy, David R; Burrack, Hannah J

    2014-01-01

    Wild bees provide important pollination services to agroecoystems, but the mechanisms which underlie their contribution to ecosystem functioning--and, therefore, their importance in maintaining and enhancing these services-remain unclear. We evaluated several mechanisms through which wild bees contribute to crop productivity, the stability of pollinator visitation, and the efficiency of individual pollinators in a highly bee-pollination dependent plant, highbush blueberry. We surveyed the bee community (through transect sampling and pan trapping) and measured pollination of both open- and singly-visited flowers. We found that the abundance of managed honey bees, Apis mellifera, and wild-bee richness were equally important in describing resulting open pollination. Wild-bee richness was a better predictor of pollination than wild-bee abundance. We also found evidence suggesting pollinator visitation (and subsequent pollination) are stabilized through the differential response of bee taxa to weather (i.e., response diversity). Variation in the individual visit efficiency of A. mellifera and the southeastern blueberry bee, Habropoda laboriosa, a wild specialist, was not associated with changes in the pollinator community. Our findings add to a growing literature that diverse pollinator communities provide more stable and productive ecosystem services.

  9. Defining a breeding objective for Nile tilapia that takes into account the diversity of smallholder production systems.

    Science.gov (United States)

    Omasaki, S K; van Arendonk, J A M; Kahi, A K; Komen, H

    2016-10-01

    In general, livestock and fish farming systems in developing countries tend to be highly diverse in terms of agro-ecological conditions and market orientation. There are no studies that have investigated if and how this diversity translates to varying preferences for breeding objective traits. This is particularly important for breeding programmes that are organized on a national level (e.g. government-supported nucleus breeding programmes). The aim of this study was to investigate whether Nile tilapia farmers with diverse production systems and economic constraints have different preferences for breeding objective traits. The second objective was to derive a consensus breeding goal, using weighted goal programming that could be used for a national breeding programme for Nile tilapia. A survey was conducted among 100 smallholder Nile tilapia farmers in Kenya to obtain preference values for traits of economic importance, by using multiple pairwise comparisons. Individual and group preference values were estimated using analytical hierarchy process. Low-income farmers preferred harvest weight, while medium- and high-income farmers preferred growth rate and survival. Grouping farmers according to market objective (fingerling production or fattening) showed that fingerling producers preferred growth rate and survival, while fattening farmers preferred harvest weight, height and thickness. Weighted goal programming was used to obtain consensus preference values, and these were used to derive desired gains for a breeding goal of a national breeding programme that takes into account the diversity of smallholder production systems. © 2016 Blackwell Verlag GmbH.

  10. Beauveria bassiana: quercetinase production and genetic diversity

    Directory of Open Access Journals (Sweden)

    Eula Maria de M. B Costa

    2011-03-01

    Full Text Available Beauveria bassiana genetic diversity and ability to synthesize quercetin 2,3-dioxygenase (quercetinase were analyzed. B. bassiana isolates, obtained from Brazilian soil samples, produced quercetinase after induction using 0.5 g/L quercetin. B. bassiana ATCC 7159 (29.6 nmol/mL/min and isolate IP 11 (27.5 nmol/ml/min showed the best performances and IP 3a (9.5 nmol/mL/min presented the lowest level of quercetinase activity in the culture supernatant. A high level of polymorphism was detected by random amplified polymorphic DNA (RAPD analysis. The use of internal-transcribed-spacer ribosomal region restriction fragment length polymorphism (ITS-RFLP did not reveal characteristic markers to differentiate isolates. However, the ITS1-5.8S-ITS2 region sequence analysis provided more information on polymorphism among the isolates, allowing them to be clustered by relative similarity into three large groups. Correlation was tested according to the Person's correlation. Data of our studies showed, that lower associations among groups, level of quercetinase production, or geographical origin could be observed. This study presents the production of a novel biocatalyst by B. bassiana and suggests the possible industrial application of this fungal species in large-scale biotechnological manufacture of quercetinase.

  11. Beauveria bassiana: Quercetinase production and genetic diversity

    Science.gov (United States)

    Eula Maria de M. B., Costa; Fabiana Cristina, Pimenta; Christian, Luz; Valéria de, Oliveira; Marília, Oliveira; Elda, Bueno; Silvana, Petrofeza

    2011-01-01

    Beauveria bassiana genetic diversity and ability to synthesize quercetin 2,3-dioxygenase (quercetinase) were analyzed. B. bassiana isolates, obtained from Brazilian soil samples, produced quercetinase after induction using 0.5 g/L quercetin. B. bassiana ATCC 7159 (29.6 nmol/mL/min) and isolate IP 11 (27.5 nmol/ml/min) showed the best performances and IP 3a (9.5 nmol/mL/min) presented the lowest level of quercetinase activity in the culture supernatant. A high level of polymorphism was detected by random amplified polymorphic DNA (RAPD) analysis. The use of internal-transcribed-spacer ribosomal region restriction fragment length polymorphism (ITS-RFLP) did not reveal characteristic markers to differentiate isolates. However, the ITS1-5.8S-ITS2 region sequence analysis provided more information on polymorphism among the isolates, allowing them to be clustered by relative similarity into three large groups. Correlation was tested according to the Person's correlation. Data of our studies showed, that lower associations among groups, level of quercetinase production, or geographical origin could be observed. This study presents the production of a novel biocatalyst by B. bassiana and suggests the possible industrial application of this fungal species in large-scale biotechnological manufacture of quercetinase. PMID:24031599

  12. Does species diversity limit productivity in natural grassland communities?

    NARCIS (Netherlands)

    Grace, James B.; Anderson, T. Michael; Smith, Melinda D.; Seabloom, Eric; Andelman, Sandy J.; Meche, Gayna; Weiher, Evan; Allain, Larry K.; Jutila, Heli; Sankaran, Mahesh; Knops, Johannes; Ritchie, Mark; Willig, Michael R.

    Theoretical analyses and experimental studies of synthesized assemblages indicate that under particular circumstances species diversity can enhance community productivity through niche complementarity. It remains unclear whether this process has important effects in mature natural ecosystems where

  13. High occurrence and unusual serotype diversity of non-typhoidal Salmonella in non-clinical niches, Angola.

    Science.gov (United States)

    Antunes, P; Campos, J; Mourão, J; Ribeiro, T G; Novais, C; Peixe, L

    2017-04-01

    Non-typhoidal Salmonella is an important burden, particularly in developing countries of the African region. We report for the first time in Angola, a sub-Saharan African country with commercial/travel relationships with Europe, an unexpectedly high occurrence of Salmonella (n = 12/63, 19%) from a high diversity of sources, particularly farm and wild animals. The detection of diverse serotypes (n = 12), involving putative new S. enterica subsp. salamae serotypes, is also of note, reinforcing the need for a comprehensive surveillance in Angola critical to identify animal/food/environmental sources of salmonellosis with impact on animal health, local people, tourists and exported products.

  14. Enhanced interannual precipitation variability increases plant functional diversity that in turn ameliorates negative impact on productivity.

    Science.gov (United States)

    Gherardi, Laureano A; Sala, Osvaldo E

    2015-12-01

    Although precipitation interannual variability is projected to increase due to climate change, effects of changes in precipitation variance have received considerable less attention than effects of changes in the mean state of climate. Interannual precipitation variability effects on functional diversity and its consequences for ecosystem functioning are assessed here using a 6-year rainfall manipulation experiment. Five precipitation treatments were switched annually resulting in increased levels of precipitation variability while maintaining average precipitation constant. Functional diversity showed a positive response to increased variability due to increased evenness. Dominant grasses decreased and rare plant functional types increased in abundance because grasses showed a hump-shaped response to precipitation with a maximum around modal precipitation, whereas rare species peaked at high precipitation values. Increased functional diversity ameliorated negative effects of precipitation variability on primary production. Rare species buffered the effect of precipitation variability on the variability in total productivity because their variance decreases with increasing precipitation variance. © 2015 John Wiley & Sons Ltd/CNRS.

  15. Interactive Effects of Diversity and Biomass on Productivity: Insights from Succession

    Science.gov (United States)

    Qinfeng Guo

    2008-01-01

    Do commonly observed spatial relationships also exist over time? As an example of attempting to answer this question, this article examines whether the frequently observed diversity-biomass-productivity-relationships over space can also be seen over time. Syntheses of long-term data and literature show that when the full successional cycles are examined, diversity and...

  16. Natural product diversity of actinobacteria in the Atacama Desert.

    Science.gov (United States)

    Rateb, Mostafa E; Ebel, Rainer; Jaspars, Marcel

    2018-02-14

    The Atacama Desert of northern Chile is considered one of the most arid and extreme environment on Earth. Its core region was described as featuring "Mars-like" soils that were at one point deemed too extreme for life to exist. However, recent investigations confirmed the presence of diverse culturable actinobacteria. In the current review, we discuss a total of 46 natural products isolated to date representing diverse chemical classes characterized from different actinobacteria isolated from various locations in the Atacama Desert. Their reported biological activities are also discussed.

  17. Diversity of condensed tannin structures affects rumen in vitro methane production in sainfoin (Onobrychis viciifolia) accessions

    NARCIS (Netherlands)

    Hatew, B.; Hayot Carbonero, C.; Stringano, E.; Sales, L. F.; Smith, L. M J; Mueller-Harvey, I.; Hendriks, W. H.; Pellikaan, W. F.

    2015-01-01

    Sainfoin is a non-bloating temperate forage legume with a moderate-to-high condensed tannin (CT) content. This study investigated whether the diversity of sainfoin accessions in terms of CT structures and contents could be related to rumen in vitro gas and methane (CH4) production and fermentation

  18. Flow cytometric monitoring of bacterioplankton phenotypic diversity predicts high population-specific feeding rates by invasive dreissenid mussels.

    Science.gov (United States)

    Props, Ruben; Schmidt, Marian L; Heyse, Jasmine; Vanderploeg, Henry A; Boon, Nico; Denef, Vincent J

    2018-02-01

    Species invasion is an important disturbance to ecosystems worldwide, yet knowledge about the impacts of invasive species on bacterial communities remains sparse. Using a novel approach, we simultaneously detected phenotypic and derived taxonomic change in a natural bacterioplankton community when subjected to feeding pressure by quagga mussels, a widespread aquatic invasive species. We detected a significant decrease in diversity within 1 h of feeding and a total diversity loss of 11.6 ± 4.1% after 3 h. This loss of microbial diversity was caused by the selective removal of high nucleic acid populations (29 ± 5% after 3 h). We were able to track the community diversity at high temporal resolution by calculating phenotypic diversity estimates from flow cytometry (FCM) data of minute amounts of sample. Through parallel FCM and 16S rRNA gene amplicon sequencing analysis of environments spanning a broad diversity range, we showed that the two approaches resulted in highly correlated diversity measures and captured the same seasonal and lake-specific patterns in community composition. Based on our results, we predict that selective feeding by invasive dreissenid mussels directly impacts the microbial component of the carbon cycle, as it may drive bacterioplankton communities toward less diverse and potentially less productive states. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  19. Genetic diversity within honeybee colonies increases signal production by waggle-dancing foragers

    Science.gov (United States)

    Mattila, Heather R; Burke, Kelly M; Seeley, Thomas D

    2008-01-01

    Recent work has demonstrated considerable benefits of intracolonial genetic diversity for the productivity of honeybee colonies: single-patriline colonies have depressed foraging rates, smaller food stores and slower weight gain relative to multiple-patriline colonies. We explored whether differences in the use of foraging-related communication behaviour (waggle dances and shaking signals) underlie differences in foraging effort of genetically diverse and genetically uniform colonies. We created three pairs of colonies; each pair had one colony headed by a multiply mated queen (inseminated by 15 drones) and one colony headed by a singly mated queen. For each pair, we monitored the production of foraging-related signals over the course of 3 days. Foragers in genetically diverse colonies had substantially more information available to them about food resources than foragers in uniform colonies. On average, in genetically diverse colonies compared with genetically uniform colonies, 36% more waggle dances were identified daily, dancers performed 62% more waggle runs per dance, foragers reported food discoveries that were farther from the nest and 91% more shaking signals were exchanged among workers each morning prior to foraging. Extreme polyandry by honeybee queens enhances the production of worker–worker communication signals that facilitate the swift discovery and exploitation of food resources. PMID:18198143

  20. Low Functional β-Diversity Despite High Taxonomic β-Diversity among Tropical Estuarine Fish Communities

    Science.gov (United States)

    Villéger, Sébastien; Miranda, Julia Ramos; Hernandez, Domingo Flores; Mouillot, David

    2012-01-01

    The concept of β-diversity, defined as dissimilarity among communities, has been widely used to investigate biodiversity patterns and community assembly rules. However, in ecosystems with high taxonomic β-diversity, due to marked environmental gradients, the level of functional β-diversity among communities is largely overlooked while it may reveal processes shaping community structure. Here, decomposing biodiversity indices into α (local) and γ (regional) components, we estimated taxonomic and functional β-diversity among tropical estuarine fish communities, through space and time. We found extremely low functional β-diversity values among fish communities (diversities, α and γ functional diversities were very close to the minimal value. These patterns were caused by two dominant functional groups which maintained a similar functional structure over space and time, despite the strong dissimilarity in taxonomic structure along environmental gradients. Our findings suggest that taxonomic and functional β-diversity deserve to be quantified simultaneously since these two facets can show contrasting patterns and the differences can in turn shed light on community assembly rules. PMID:22792395

  1. Commercial Plant Production and Consumption Still Follow the Latitudinal Gradient in Species Diversity despite Economic Globalization.

    Science.gov (United States)

    Nelson, Erik J; Helmus, Matthew R; Cavender-Bares, Jeannine; Polasky, Stephen; Lasky, Jesse R; Zanne, Amy E; Pearse, William D; Kraft, Nathan J B; Miteva, Daniela A; Fagan, William F

    2016-01-01

    Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers). According to the economic theory of comparative advantage, countries open to trade will be able to consume more-in terms of volume and diversity-if they concentrate production on commodities that they can most cost-effectively produce, while importing goods that are expensive to produce, relative to other countries. Here, we perform a global analysis of traded commercial plant products and find little evidence that increasing globalization has incentivized agricultural specialization. Instead, a country's plant production and consumption patterns are still largely determined by local evolutionary legacies of plant diversification. Because tropical countries harbor a greater diversity of lineages across the tree of life than temperate countries, tropical countries produce and consume a greater diversity of plant products than do temperate countries. In contrast, the richer and more economically advanced temperate countries have the capacity to produce and consume more plant species than the generally poorer tropical countries, yet this collection of plant species is drawn from fewer branches on the tree of life. Why have countries not increasingly specialized in plant production despite the theoretical financial incentive to do so? Potential explanations include the persistence of domestic agricultural subsidies that distort production decisions, cultural preferences for diverse local food production, and that diverse food production protects rural households in developing countries from food price shocks. Less specialized production patterns will make crop systems more resilient to zonal climatic and social perturbations, but this may come at the expense of global crop production efficiency, an important step in making the transition to a hotter and more

  2. Commercial Plant Production and Consumption Still Follow the Latitudinal Gradient in Species Diversity despite Economic Globalization.

    Directory of Open Access Journals (Sweden)

    Erik J Nelson

    Full Text Available Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers. According to the economic theory of comparative advantage, countries open to trade will be able to consume more-in terms of volume and diversity-if they concentrate production on commodities that they can most cost-effectively produce, while importing goods that are expensive to produce, relative to other countries. Here, we perform a global analysis of traded commercial plant products and find little evidence that increasing globalization has incentivized agricultural specialization. Instead, a country's plant production and consumption patterns are still largely determined by local evolutionary legacies of plant diversification. Because tropical countries harbor a greater diversity of lineages across the tree of life than temperate countries, tropical countries produce and consume a greater diversity of plant products than do temperate countries. In contrast, the richer and more economically advanced temperate countries have the capacity to produce and consume more plant species than the generally poorer tropical countries, yet this collection of plant species is drawn from fewer branches on the tree of life. Why have countries not increasingly specialized in plant production despite the theoretical financial incentive to do so? Potential explanations include the persistence of domestic agricultural subsidies that distort production decisions, cultural preferences for diverse local food production, and that diverse food production protects rural households in developing countries from food price shocks. Less specialized production patterns will make crop systems more resilient to zonal climatic and social perturbations, but this may come at the expense of global crop production efficiency, an important step in making the transition to a

  3. Perceptions of Diversity Training Needs in High Tech Business.

    Science.gov (United States)

    Lieberman, Devorah A.; Gurtov, Ellene

    A study questioned 12 human resource personnel, corporation managers, and diversity trainers about their perceptions of diversity training needs in Pacific Northwest high tech organizations. The overarching research questions for the study were as follows: (1) What are the most frequently reported diversity training needs among human resource…

  4. Global patterns of workplace productivity for people with depression: absenteeism and presenteeism costs across eight diverse countries

    OpenAIRE

    Evans-Lacko, S.; Knapp, M.

    2016-01-01

    Purpose Depression is a leading cause of disability worldwide. Research suggests that by far, the greatest contributor to the overall economic impact of depression is loss in productivity; however, there is very little research on the costs of depression outside of Western high-income countries. Thus, this study examines the impact of depression on workplace productivity across eight diverse countries. Methods We estimated the extent and costs of depression-related absenteeism and presenteeis...

  5. Yeast diversity and dynamics in the production processes of Norwegian dry-cured meat products.

    Science.gov (United States)

    Asefa, Dereje T; Møretrø, Trond; Gjerde, Ragnhild O; Langsrud, Solveig; Kure, Cathrine F; Sidhu, Maan S; Nesbakken, Truls; Skaar, Ida

    2009-07-31

    This study investigate the diversity and dynamics of yeasts in the production processes of one unsmoked and two smoked dry-cured meat products of a Norwegian dry-cured meat production facility. A longitudinal observational study was performed to collect 642 samples from the meat, production materials, room installations and indoor and outdoor air of the production facility. Nutrient rich agar media were used to isolate the yeasts. Morphologically different isolates were re-cultivated in their pure culture forms. Both classical and molecular methods were employed for species identification. Totally, 401 yeast isolates belonging to 10 species of the following six genera were identified: Debaryomyces, Candida, Rhodotorula, Rhodosporidium, Cryptococcus and Sporidiobolus. Debaryomyces hansenii and Candida zeylanoides were dominant and contributed by 63.0% and 26.4% respectively to the total isolates recovered from both smoked and unsmoked products. The yeast diversity was higher at the pre-salting production processes with C. zeylanoides being the dominant. Later at the post-salting stages, D. hansenii occurred frequently. Laboratory studies showed that D. hansenii was more tolerant to sodium chloride and nitrite than C. zeylanoides. Smoking seems to have a killing or a temporary growth inhibiting effect on yeasts that extend to the start of the drying process. Yeasts were isolated only from 31.1% of the environmental samples. They belonged to six different species of which five of them were isolated from the meat samples too. Debaryomyces hansenii and Rhodotorula glutinis were dominant with a 62.6% and 22.0% contribution respectively. As none of the air samples contained D. hansenii, the production materials and room installations used in the production processes were believed to be the sources of contamination. The dominance of D. hansenii late in the production process replacing C. zeylanoides should be considered as a positive change both for the quality and safety

  6. beta-diversity and species accumulation in antarctic coastal benthos: influence of habitat, distance and productivity on ecological connectivity.

    Directory of Open Access Journals (Sweden)

    Simon F Thrush

    Full Text Available High Antarctic coastal marine environments are comparatively pristine with strong environmental gradients, which make them important places to investigate biodiversity relationships. Defining how different environmental features contribute to shifts in beta-diversity is especially important as these shifts reflect both spatio-temporal variations in species richness and the degree of ecological separation between local and regional species pools. We used complementary techniques (species accumulation models, multivariate variance partitioning and generalized linear models to assess how the roles of productivity, bio-physical habitat heterogeneity and connectivity change with spatial scales from metres to 100's of km. Our results demonstrated that the relative importance of specific processes influencing species accumulation and beta-diversity changed with increasing spatial scale, and that patterns were never driven by only one factor. Bio-physical habitat heterogeneity had a strong influence on beta-diversity at scales 40 km. Our analysis supports the emphasis on the analysis of diversity relationships across multiple spatial scales and highlights the unequal connectivity of individual sites to the regional species pool. This has important implications for resilience to habitat loss and community homogenisation, especially for Antarctic benthic communities where rates of recovery from disturbance are slow, there is a high ratio of poor-dispersing and brooding species, and high biogenic habitat heterogeneity and spatio-temporal variability in primary production make the system vulnerable to disturbance. Consequently, large areas need to be included within marine protected areas for effective management and conservation of these special ecosystems in the face of increasing anthropogenic disturbance.

  7. beta-diversity and species accumulation in antarctic coastal benthos: influence of habitat, distance and productivity on ecological connectivity.

    Science.gov (United States)

    Thrush, Simon F; Hewitt, Judi E; Cummings, Vonda J; Norkko, Alf; Chiantore, Mariachiara

    2010-07-30

    High Antarctic coastal marine environments are comparatively pristine with strong environmental gradients, which make them important places to investigate biodiversity relationships. Defining how different environmental features contribute to shifts in beta-diversity is especially important as these shifts reflect both spatio-temporal variations in species richness and the degree of ecological separation between local and regional species pools. We used complementary techniques (species accumulation models, multivariate variance partitioning and generalized linear models) to assess how the roles of productivity, bio-physical habitat heterogeneity and connectivity change with spatial scales from metres to 100's of km. Our results demonstrated that the relative importance of specific processes influencing species accumulation and beta-diversity changed with increasing spatial scale, and that patterns were never driven by only one factor. Bio-physical habitat heterogeneity had a strong influence on beta-diversity at scales 40 km. Our analysis supports the emphasis on the analysis of diversity relationships across multiple spatial scales and highlights the unequal connectivity of individual sites to the regional species pool. This has important implications for resilience to habitat loss and community homogenisation, especially for Antarctic benthic communities where rates of recovery from disturbance are slow, there is a high ratio of poor-dispersing and brooding species, and high biogenic habitat heterogeneity and spatio-temporal variability in primary production make the system vulnerable to disturbance. Consequently, large areas need to be included within marine protected areas for effective management and conservation of these special ecosystems in the face of increasing anthropogenic disturbance.

  8. Understanding Students' Precollege Experiences with Racial Diversity: The High School as Microsystem

    Science.gov (United States)

    Park, Julie J.; Chang, Stephanie H.

    2015-01-01

    Few qualitative studies consider how high school experiences affect readiness for diversity engagement in college. Using data from an ethnographic case study, three central trends (student experiences within homogeneous high schools, racial divisions within diverse high schools, and students who attended diverse high schools but had little…

  9. Isolation of lactobacillus reuteri from Peyer's patches and their effects on sIgA production and gut microbiota diversity.

    Science.gov (United States)

    Wang, Panpan; Li, Ya; Xiao, Hang; Shi, Yonghui; Le, Guo-Wei; Sun, Jin

    2016-09-01

    We previously reported that specific Lactobacillus reuteri colonized within mouse Peyer's patches (PP) effectively prevented high fat diet induced obesity and low-grade chronic inflammation. We further investigated the role of PP Lactobacillus reuteri on sIgA production in rats in this study. Lactobacilli were isolated from rat PP. All isolates were L. reuteri and belonged to three phenotypes according to amplified fragment length polymorphism analysis. Typical strains of two main clusters, PP1 and PP2, were used to treat control and vitamin A deficient (VAD) rats, respectively. The feeding of PP1 and PP2 affected sIgA and Lactobacillus diversity by strain-specific manner. Free sIgA was significantly increased by PP1 (p = 0.069) and PP2 (p Lactobacillus diversity in the control rats (p Lactobacillus diversity in both control and VAD rats. Fecal sIgA was correlated with PP Lactobacillus diversity (R(2) = 0.7958, p = 0.011). Modulation of sIgA production by PP L. reuteri of rat is dependent on vitamin A and change of Lactobacillus diversity in PP. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Knowledge Diversity, Transfer and Coordination

    DEFF Research Database (Denmark)

    Laursen, Keld; Moreira, Solon; Markus, Arjan

    from the widely accepted view that distant, externally-developed knowledge is difficult to incorporate into the focal firm?s own production. We suggest that high levels of intrafirm network diversity, tie strength, and network density are essential for a diversity of knowledge inputs, knowledge...

  11. Commercial Plant Production and Consumption Still Follow the Latitudinal Gradient in Species Diversity despite Economic Globalization

    Science.gov (United States)

    Nelson, Erik J.; Helmus, Matthew R.; Cavender-Bares, Jeannine; Polasky, Stephen; Lasky, Jesse R.; Zanne, Amy E.; Pearse, William D.; Kraft, Nathan J. B.; Miteva, Daniela A.; Fagan, William F.

    2016-01-01

    Increasing trade between countries and gains in income have given consumers around the world access to a richer and more diverse set of commercial plant products (i.e., foods and fibers produced by farmers). According to the economic theory of comparative advantage, countries open to trade will be able to consume more–in terms of volume and diversity–if they concentrate production on commodities that they can most cost-effectively produce, while importing goods that are expensive to produce, relative to other countries. Here, we perform a global analysis of traded commercial plant products and find little evidence that increasing globalization has incentivized agricultural specialization. Instead, a country’s plant production and consumption patterns are still largely determined by local evolutionary legacies of plant diversification. Because tropical countries harbor a greater diversity of lineages across the tree of life than temperate countries, tropical countries produce and consume a greater diversity of plant products than do temperate countries. In contrast, the richer and more economically advanced temperate countries have the capacity to produce and consume more plant species than the generally poorer tropical countries, yet this collection of plant species is drawn from fewer branches on the tree of life. Why have countries not increasingly specialized in plant production despite the theoretical financial incentive to do so? Potential explanations include the persistence of domestic agricultural subsidies that distort production decisions, cultural preferences for diverse local food production, and that diverse food production protects rural households in developing countries from food price shocks. Less specialized production patterns will make crop systems more resilient to zonal climatic and social perturbations, but this may come at the expense of global crop production efficiency, an important step in making the transition to a hotter and more

  12. Hybridization and adaptive evolution of diverse Saccharomyces species for cellulosic biofuel production.

    Science.gov (United States)

    Peris, David; Moriarty, Ryan V; Alexander, William G; Baker, EmilyClare; Sylvester, Kayla; Sardi, Maria; Langdon, Quinn K; Libkind, Diego; Wang, Qi-Ming; Bai, Feng-Yan; Leducq, Jean-Baptiste; Charron, Guillaume; Landry, Christian R; Sampaio, José Paulo; Gonçalves, Paula; Hyma, Katie E; Fay, Justin C; Sato, Trey K; Hittinger, Chris Todd

    2017-01-01

    cellulosic biofuel production. Notably, Saccharomyces mikatae strains have high innate tolerance to hydrolysate toxins, while some Saccharomyces species have a robust native capacity to consume xylose. This research demonstrates that hybridization is a viable method to combine industrially relevant traits from diverse yeast species and that members of the genus Saccharomyces beyond S. cerevisiae may offer advantageous genes and traits of interest to the lignocellulosic biofuel industry.

  13. Primary productivity as a control over soil microbial diversity along environmental gradients in a polar desert ecosystem

    Directory of Open Access Journals (Sweden)

    Kevin M. Geyer

    2017-07-01

    Full Text Available Primary production is the fundamental source of energy to foodwebs and ecosystems, and is thus an important constraint on soil communities. This coupling is particularly evident in polar terrestrial ecosystems where biological diversity and activity is tightly constrained by edaphic gradients of productivity (e.g., soil moisture, organic carbon availability and geochemical severity (e.g., pH, electrical conductivity. In the McMurdo Dry Valleys of Antarctica, environmental gradients determine numerous properties of soil communities and yet relatively few estimates of gross or net primary productivity (GPP, NPP exist for this region. Here we describe a survey utilizing pulse amplitude modulation (PAM fluorometry to estimate rates of GPP across a broad environmental gradient along with belowground microbial diversity and decomposition. PAM estimates of GPP ranged from an average of 0.27 μmol O2/m2/s in the most arid soils to an average of 6.97 μmol O2/m2/s in the most productive soils, the latter equivalent to 217 g C/m2/y in annual NPP assuming a 60 day growing season. A diversity index of four carbon-acquiring enzyme activities also increased with soil productivity, suggesting that the diversity of organic substrates in mesic environments may be an additional driver of microbial diversity. Overall, soil productivity was a stronger predictor of microbial diversity and enzymatic activity than any estimate of geochemical severity. These results highlight the fundamental role of environmental gradients to control community diversity and the dynamics of ecosystem-scale carbon pools in arid systems.

  14. Relationship of subseafloor microbial diversity to sediment age and organic carbon content

    Science.gov (United States)

    Walsh, E. A.; Kirkpatrick, J. B.; Sogin, M. L.; D'Hondt, S. L.

    2013-12-01

    Our tag pyrosequencing investigation of four globally distant sites reveals sediment age and total organic carbon content to be significant components in understanding subseafloor diversity. Our sampling locations include two sites from high-productivity regions (Indian Ocean and Bering Sea) and two from moderate-productivity (eastern and central equatorial Pacific Ocean). Sediment from the high-productivity sites has much higher TOC than sediment from the moderate-productivity equatorial sites. We applied a high-resolution 16S V4-V6 tag pyrosequencing approach to 24 bacterial and 17 archaeal samples, totaling 602,502 reads. We identified1,291 archaeal and 15,910 bacterial OTUs (97%) from these reads. We analyzed bacterial samples from all four sites in addition to archaeal samples from our high productivity sites. These high productivity, high TOC sites have a pronounced methane-rich sulfate-free zone at depth from which archaea have been previously considered to dominate (Biddle et al., 2006). At all four locations, microbial diversity is highest near the seafloor and drops rapidly to low but stable values with increasing sediment depth. The depth at which diversity stabilizes varies greatly from site to site, but the age at which it stabilizes is relatively constant. At all four sites, diversity reaches low stable values a few hundred thousand years after sediment deposition. The sites with high total organic carbon (high productivity sites) generally exhibit higher diversity at each sediment age than the sites with lower total organic carbon (moderate-productivity sites). Archaeal diversity is lower than bacterial diversity at every sampled depth. Biddle, J.F., Lipp, J.S., Lever, M.A., Lloyd, K.G., Sørensen, K.B., Anderson, R. et al. (2006) Heterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru. PNAS 103: 3846-3851.

  15. Does Labor Diversity Affect Firm Productivity?

    DEFF Research Database (Denmark)

    Parrotta, Pierpaolo; Pozzoli, Dario; Pytlikova, Mariola

    /education signi?cantly enhances ?rm performance as measured by ?rm TFP. Conversely, diversity in demographics and ethnicity brings mixed results - both dimensions of workforce diversity have either no or negative e?ects on ?rm TFP. Hence, it seems as if the negative e?ects, coming from communication...... and integration costs connected to a more demographically and culturally diverse workforce, counteract the positive e?ects of diversity on ?rm TFP, coming from creativity and knowledge spillovers. However, we ?nd that ethnic diversity is valuable for ?rms operating in industries characterized by above......-average trade openness, giving support to the hypothesis that an ethnically diverse workforce provides information and access to global markets....

  16. Effect of nitrate addition on prokaryotic diversity and the activity of sulfate-reducing prokaryotes in high-temperature oil production systems

    DEFF Research Database (Denmark)

    Gittel, Antje; Wieczorek, Adam; Sørensen, Ketil

    Adding nitrate to injection water is a possible strategy to control the activity of sulfate-reducing prokaryotes (SRP) in oil production system. To assess the effects of nitrate addition, prokaryotic diversity (Bacteria, Archaea, SRP) and SRP activity were studied in the production waters......-treated site was additionally supported by demonstrating their potential activity at 58°C, indicating that the troublesome SRP were pipeline-derived. Consistent with the low frequency of SRP in the clone libraries, no activity could be shown for samples from the nitrate-treated system suggesting that SRP were...... inhibited by nitrate addition. Visualization and quantification of the identified troublesome prokaryotes and potential competitors using the CARD-FISH technique will be performed on production water from both sites....

  17. A diversity oriented synthesis of natural product inspired molecular libraries.

    Science.gov (United States)

    Chauhan, Jyoti; Luthra, Tania; Gundla, Rambabu; Ferraro, Antonio; Holzgrabe, Ulrike; Sen, Subhabrata

    2017-11-07

    Natural products are the source of innumerable pharmaceutical drug candidates and also form an important aspect of herbal remedies. They are also a source of various bioactive compounds. Herein we have leveraged the structural attributes of several natural products in building a library of architecturally diverse chiral molecules by harnessing R-tryptophan as the chiral auxiliary. It is converted to its corresponding methyl ester 1 which in turn provided a bevy of 1-aryl-tetrahydro-β-carbolines 2a-d, which were then converted to chiral compounds via a diversity oriented synthetic strategy (DOS). In general, intermolecular and intramolecular ring rearrangements facilitated the formation of the final compounds. Four different classes of molecules with distinct architectures were generated, adding up to nearly twenty-two individual molecules. Phenotypic screening of a representative section of the library revealed two molecules that selectively inhibit MCF7 breast cancer cells with IC 50 of ∼5 μg mL -1 potency.

  18. Diversity of governance arrangements for indigenous natural products in communal areas of Namibia

    NARCIS (Netherlands)

    Ndeinoma, A.; Wiersum, K.F.

    2017-01-01

    In several countries, it has been observed that development of policies and regulations for non-timber forest products (NTFPs) rarely follows a systematic approach. This paper characterises the diversity of governance arrangements for accessing and marketing indigenous natural products in communal

  19. Embracing "Soft Skill" Diversity in the Workplace (Invited)

    Science.gov (United States)

    Thomas, T.

    2010-12-01

    Embracing "Soft Skill" Diversity in the Workplace Terri Thomas, Sr. Director Global Customer Support ShoreTel INRODUCTION Truly successful diversity programs go beyond gender, age, ethnicity, race, sexual orientation and spiritual practice. They include diversity of thought, style, leadership and communication styles, the so called “soft skills”. The increasing need for global workforces is stronger than ever and high performance teams have fully embraced, successfully harnessed and put into practice robust diversity programs than include a “soft skill” focus. Managing diversity presents significant organizational challenges, and is not an easy task, particularly in organizations that are heavily weighted with highly technical professionals such as engineers, accountants etc.. The focus of this presentation is on leveraging the “Soft Skills” diversity in technical work environments to create high performance and highly productive teams. WHY DIVERSITY and WHY NOW? Due to increasing changes in the U.S. population, in order to stay competitive, companies need to focus on diversity and look for ways to become inclusive organizations because diversity has the potential of yielding greater productivity and competitive advantages . Managing and valuing diversity is a key component of effective people management, which can improve workplace productivity (Black Enterprise, 2001). Changing demographics, from organizational restructuring, women in the workplace, equal opportunity legislation and other legal issues, are forcing organizations to become more aggressive in implementing robust diversity practices. However, YOU do not need to wait for your organization to introduce a formal “Diversity” program. There are steps you can take to introduce diversity into your own workgroups. There is no “one single answer” to solve this issue, however this discussion will provide thought provoking ideas, examples of success and failure and a starting point for you

  20. Modeling the Effects of Trait Diversity on Short-term Adaptive Capacity and Long-term Productivity of Phytoplankton Communities

    Science.gov (United States)

    Smith, S. L.; Vallina, S. M.; Merico, A.

    2016-02-01

    We examine Biodiversity and Ecosystem Function (BEF) in a model phytoplankton community, using two recently developed mechanisms for sustaining diversity. The Trait Diffusion (TD) formulation represents the maintenance of diversity via endogenous mechanisms, such as inter-generational trait plasticity and rapid evolution. The 'Kill-the-Winner' (KTW) formulation for grazing sustains prey biodiversity via the exogenous mechanism of active prey switching. We implement both TD and KTW in a continuous trait-distribution model using simplified size-scalings to define a gleaner-opportunist trade-off for a phytoplankton community. By simulating semi-continuous culture experiments with periodic external dilutions, we test the dynamic response of the phytoplankton community to different scenarios of pulsed nutrient supply. We quantify the short-term Adaptive Capacity (AC) of the community by the specific growth rate averaged over the first 3 days of perturbations, and the Long-term Productivity (LP) by its average over the entire 120 day period of perturbations. When either the frequency or intensity of pulses is low, both AC and LP tend to decrease with diversity (and vice versa). Trait diversity has more impact on AC, particularly for pulses of high frequency or intensity, for which it tends to increase gradually at first, then steeply, and then to saturate with increasing diversity. For pulses of moderate intensity and frequency, increasing trait diversity from low to moderate levels leads to a trade-off between enhancing AC while slightly decreasing LP. Ultimately, we find that sustaining diversity increases the speed at which the phytoplankton community changes its composition in terms of size and hence nutrient acquisition traits, which may have implications for the transfer of productivity through the foodweb.

  1. Plant diversity surpasses plant functional groups and plant productivity as driver of soil biota in the long term.

    Directory of Open Access Journals (Sweden)

    Nico Eisenhauer

    2011-01-01

    Full Text Available One of the most significant consequences of contemporary global change is the rapid decline of biodiversity in many ecosystems. Knowledge of the consequences of biodiversity loss in terrestrial ecosystems is largely restricted to single ecosystem functions. Impacts of key plant functional groups on soil biota are considered to be more important than those of plant diversity; however, current knowledge mainly relies on short-term experiments.We studied changes in the impacts of plant diversity and presence of key functional groups on soil biota by investigating the performance of soil microorganisms and soil fauna two, four and six years after the establishment of model grasslands. The results indicate that temporal changes of plant community effects depend on the trophic affiliation of soil animals: plant diversity effects on decomposers only occurred after six years, changed little in herbivores, but occurred in predators after two years. The results suggest that plant diversity, in terms of species and functional group richness, is the most important plant community property affecting soil biota, exceeding the relevance of plant above- and belowground productivity and the presence of key plant functional groups, i.e. grasses and legumes, with the relevance of the latter decreasing in time.Plant diversity effects on biota are not only due to the presence of key plant functional groups or plant productivity highlighting the importance of diverse and high-quality plant derived resources, and supporting the validity of the singular hypothesis for soil biota. Our results demonstrate that in the long term plant diversity essentially drives the performance of soil biota questioning the paradigm that belowground communities are not affected by plant diversity and reinforcing the importance of biodiversity for ecosystem functioning.

  2. No correlation between the diversity and productivity of assemblages: evidence from the phytophage and predator assemblages in various cotton agroecosystems.

    Science.gov (United States)

    Gao, Feng; Men, XingYuan; Ge, Feng

    2014-09-01

    Biodiversity research has shown that primary productivity increases with plant species number, especially in many experimental grassland systems. Here, we assessed the correlation between productivity and diversity of phytophages and natural enemy assemblages associated with planting date and intercropping in four cotton agroecosystems. Twenty-one pairs of data were used to determine Pearson correlations between species richness, total number of individuals, diversity indices and productivity for each assemblage every five days from 5 June to 15 September 2012. At the same trophic level, the productivity exhibited a significant positive correlation with species richness of the phytophage or predator assemblage. A significant correlation was found between productivity and total number of individuals in most cotton fields. However, no significant correlations were observed between productivity and diversity indices (including indices of energy flow diversity and numerical diversity) in most cotton fields for either the phytophage or the predator assemblages. Species richness of phytophage assemblage and total individual numbers were significantly correlated with primary productivity. Also, species richness of natural enemy assemblage and total number of individuals correlated with phytophage assemblage productivity. A negative but not significant correlation occurred between the indices of numerical diversity and energy flow diversity and lower trophic-level productivity in the cotton-phytophage and phytophage-predator assemblages for most intercropped cotton agroecosystems. Our results clearly showed that there were no correlations between diversity indices and productivity within the same or lower trophic levels within the phytophage and predator assemblages in cotton agroecosystems, and inter-cropped cotton fields had a stronger ability to support the natural enemy assemblage and potentially to reduce phytophages.

  3. Protozoan Diversity in a productive fishpond of a tropical plateau ...

    African Journals Online (AJOL)

    A survey of the Protozoan species diversity in a productive fishpond of the Jos Plateau, Nigeria was investigated at 7 day interval over a period of 11 months. Samples were collected from water column and sediment. Protozoans were found to compose of the flagellates sarcodines and cilliates. There was a significant ...

  4. Response diversity, functional redundancy, and post-logging productivity in northern temperate and boreal forests.

    Science.gov (United States)

    Correia, David Laginha Pinto; Raulier, Frédéric; Bouchard, Mathieu; Filotas, Élise

    2018-04-19

    The development of efficient ecosystem resilience indicators was identified as one of the key research priorities in the improvement of existing sustainable forest management frameworks. Two indicators of tree diversity associated with ecosystem functioning have recently received particular attention in the literature: functional redundancy (FR) and response diversity (RD). We examined how these indicators could be used to predict post-logging productivity in forests of Québec, Canada. We analysed the relationships between pre-logging FR and RD, as measured with sample plots, and post-logging productivity, measured as seasonal variation in enhanced vegetation index obtained from MODIS satellite imagery. The effects of the deciduous and coniferous tree components in our pre-disturbance diversity assessments were isolated in order to examine the hypothesis that they have different impacts on post-disturbance productivity. We also examined the role of tree species richness and species identity effects. Our analysis revealed the complementary nature of traditional biodiversity indicators and trait-based approaches in the study of biodiversity-ecosystem-functioning relationships in dynamic ecosystems. We report a significant and positive relationship between pre-disturbance deciduous RD and post-disturbance productivity, as well as an unexpected significant negative effect of coniferous RD on productivity. This negative relationship with post-logging productivity likely results from slower coniferous regeneration speeds and from the relatively short temporal scale examined. Negative black-spruce-mediated identity effects were likely associated with increased stand vulnerability to paludification and invasion by ericaceous shrubs that slow down forest regeneration. Response diversity outperformed functional redundancy as a measure of post-disturbance productivity most likely due to the stand-replacing nature of the disturbance considered. To the best of our knowledge

  5. Genetic Diversity Analysis of South and East Asian Duck Populations Using Highly Polymorphic Microsatellite Markers

    Directory of Open Access Journals (Sweden)

    Dongwon Seo

    2016-04-01

    Full Text Available Native duck populations have lower productivity, and have not been developed as much as commercials duck breeds. However, native ducks have more importance in terms of genetic diversity and potentially valuable economic traits. For this reason, population discriminable genetic markers are needed for conservation and development of native ducks. In this study, 24 highly polymorphic microsatellite (MS markers were investigated using commercial ducks and native East and South Asian ducks. The average polymorphic information content (PIC value for all MS markers was 0.584, indicating high discrimination power. All populations were discriminated using 14 highly polymorphic MS markers by genetic distance and phylogenetic analysis. The results indicated that there were close genetic relationships among populations. In the structure analysis, East Asian ducks shared more haplotypes with commercial ducks than South Asian ducks, and they had more independent haplotypes than others did. These results will provide useful information for genetic diversity studies in ducks and for the development of duck traceability systems in the market.

  6. Shade tree diversity enhances coffee production and quality in agroforestry systems in the Western Ghats

    NARCIS (Netherlands)

    Nesper, Maike; Kueffer, Christoph; Krishnan, Smitha; Kushalappa, Cheppudira G.; Ghazoul, Jaboury

    2017-01-01

    Intensification of multispecies coffee agroforests reduces shade tree diversity with implications for tropical biodiversity. We investigated how tree biodiversity and its effects on coffee production and quality changes along a gradient of intensification (from diverse multispecies to Grevillea

  7. The influence of compositional and structural diversity on forest productivity

    Science.gov (United States)

    James N. Long; John D. Shaw

    2010-01-01

    Data from ~1500 ponderosa pine (Pinus ponderosa C. Lawson) stands in the western United States were used to examine the potential influence of compositional and structural diversity on forest productivity. Relative density, height and site quality were combined in a conceptually sound expression of the relationship between growth and growing stock for ponderosa pine-...

  8. Diversity and useful products in some Verbenaceous member of Melghat and Amravati regions, Maharashtra, India

    Directory of Open Access Journals (Sweden)

    SHUBHANGI NAGORAO INGOLE

    2011-07-01

    Full Text Available Ingole SN (2011 Diversity and useful products in some Verbenaceous member of Melghat and Amravati regions, Maharashtra, India. Biodiversitas 12: 146-163. Verbenaceae is a large family of very diverse habit. The present study deals with detailed characteristics, distribution and economically important products of some verbenaceous members of Melghat and Amravati regions. During the survey twenty members belonging to fourteen genera of Verbenaceae were collected. Some members occur abundantly either in wild or cultivated state like Lantana camara L. var. aculeata Mold., Lantana flava Medik., L. nivea Vent., Glandularia bipinnatifida (Schauer Nutt., Duranta erecta L., Vitex negundo L., Volkameria inermis L., Clerodendrum phlomidis L. f., Clerodendrum splendens G. Don, Nyctanthes arbor-tristis L. etc. while Petrea volubilis L., Gmelina arborea Roxb., G. phillippensis Cham., Stachytarpheta jamaicensis (L. Vahl., S. mutabilis (Jacq. Vahl., Rotheca serrata (L. Steane & Mabb., Holmskioldia sanguinea Retz. are not much common and occur in limited locations. Phyla nodiflora (L. Greene, a creeping much-branched herb is found typically in wet places. Tectona grandis L. f. occurs very variable in size according to its habitat and is common dominant tree in forest of Melghat and also planted in plains. Clerodendrum infortunatum L., a gregarious tomentose shrub is exclusively found in shades of forest at limited spots in higher elevations of Melghat. The various members are not only beautiful ornamentals but also the source of important medicinal products useful in a broad range of diseases including skin disorders and snake remedies; they contain alkaloids, sterols, saponin, glucosides, dyes etc. and are economically quite important e.g. as high quality timber. On basis of morphological diversity the generic key is provided.

  9. The influence of crop production and socioeconomic factors on seasonal household dietary diversity in Burkina Faso.

    Science.gov (United States)

    Somé, Jérôme W; Jones, Andrew D

    2018-01-01

    Households in low-income settings are vulnerable to seasonal changes in dietary diversity because of fluctuations in food availability and access. We assessed seasonal differences in household dietary diversity in Burkina Faso, and determined the extent to which household socioeconomic status and crop production diversity modify changes in dietary diversity across seasons, using data from the nationally representative 2014 Burkina Faso Continuous Multisectoral Survey (EMC). A household dietary diversity score based on nine food groups was created from household food consumption data collected during four rounds of the 2014 EMC. Plot-level crop production data, and data on household assets and education were used to create variables on crop diversity and household socioeconomic status, respectively. Analyses included data for 10,790 households for which food consumption data were available for at least one round. Accounting for repeated measurements and controlling for the complex survey design and confounding covariates using a weighted multi-level model, household dietary diversity was significantly higher during both lean seasons periods, and higher still during the harvest season as compared to the post-harvest season (mean: post-harvest: 4.76 (SE 0.04); beginning of lean: 5.13 (SE 0.05); end of lean: 5.21 (SE 0.05); harvest: 5.72 (SE 0.04)), but was not different between the beginning and the end of lean season. Seasonal differences in household dietary diversity were greater among households with higher food expenditures, greater crop production, and greater monetary value of crops sale (P<0.05). Seasonal changes in household dietary diversity in Burkina Faso may reflect nutritional differences among agricultural households, and may be modified both by households' socioeconomic status and agricultural characteristics.

  10. Five willow varieties cultivated across diverse field environments reveal stem density variation associated with high tension wood abundance

    Directory of Open Access Journals (Sweden)

    Nicolas eBerthod

    2015-10-01

    Full Text Available Sustainable and inexpensive production of biomass is necessary to make biofuel production feasible, but represents a challenge. Five short rotation coppice (SRC willow cultivars, selected for high biomass yield, were cultivated on sites at four diverse regions of Quebec to determine their bioenergy potential in contrasting environments. Wood composition and anatomical traits were characterized. Tree height and stem diameter were measured to evaluate growth performance of the cultivars according to the diverse pedoclimatic conditions. Each cultivar showed very specific responses to its environment. While no significant variation in lignin content was observed between sites, there was variation between cultivars. Surprisingly, the pattern of substantial genotype variability in stem density was maintained across all sites. However, wood anatomy did differ between sites in a cultivar (producing high and low density wood, suggesting a probable response to an abiotic stress. Furthermore, twice as many cellulose-rich G-fibers, comprising over 50 % of secondary xylem, were also found in the high density wood, a finding with potential to bring higher value to the lignocellulosic bioethanol industry

  11. Workforce diversity, productivity and wages in France: the role of managers vs. the proprietary structure of the firm

    OpenAIRE

    Garnero, Andrea

    2015-01-01

    This paper estimates the impact of workforce diversity on productivity, wages, and productivity–wage gaps in a sample of French firms using data from a comprehensive establishment-level survey (REPONSE) for 2011 matched with companies’ balance sheet data. Controlling for a wide set of workers’ and firms’ characteristics, findings suggest that age and gender diversity are negatively linked to firm’s productivity and wages while education diversity is positively linked. Contrary to some widespr...

  12. Effect of nitrate addition on the diversity and activity of sulfate-reducing prokaryotes in high-temperature oil production systems

    DEFF Research Database (Denmark)

    Gittel, Antje; Wieczorek, Adam; Sørensen, Ketil

    Sulfate-reducing prokaryotes (SRP) producing hydrogen sulfide cause severe problems like microbial corrosion, souring and plugging in seawater-injected oil production systems. Adding nitrate to the injection water is a possible strategy to control the activity of SRP by favoring the growth of both...... heterotrophic, nitrate-reducing bacteria that outcompete SRP for substrates, and nitrate-reducing, sulfide-oxidizing bacteria (NR-SOB). To assess the effects of nitrate addition, microbial diversity (Bacteria, Archaea) and SRP activity were studied in the production waters of a nitrate-treated and a non...... their potential activity under pipeline (60°C), but not under oil reservoir conditions (80°C), indicating that the troublesome SRP were pipeline-derived. Consistent with the low amount of SRP, no activity could be shown for samples from the nitrate-treated system suggesting that SRP were inhibited by nitrate...

  13. Predicting the impacts of Mississippi River diversions and sea-level rise on spatial patterns of eastern oyster growth rate and production

    Science.gov (United States)

    Wang, Hongqing; Chen, Qin; La Peyre, Megan K.; Hu, Kelin; La Peyre, Jerome F.

    2017-01-01

    There remains much debate regarding the perceived tradeoffs of using freshwater and sediment diversions for coastal restoration in terms of balancing the need for wetland restoration versus preserving eastern oyster (Crassostrea virginica) production. Further complicating the issue, climate change-induced sea-level rise (SLR) and land subsidence are also expected to affect estuarine water quality. In this study, we developed a process-based numerical modeling system that couples hydrodynamic, water quality, and oyster population dynamics. We selected Breton Sound Estuary (BSE) (∼2740 km2) in the eastern Mississippi River Deltaic Plain since it is home to several of the largest public oyster seed grounds and private leases for the Gulf coast. The coupled oyster population model was calibrated and validated against field observed oyster growth data. We predicted the responses of oyster population in BSE to small- (142 m3 s−1) and large-scale (7080 m3 s−1) river diversions at the Caernarvon Freshwater Diversion structure planned in the 2012 Coastal Master Plan (Louisiana) under low (0.38 m) and high (1.44 m) relative sea-level rise (RSLR = eustatic SLR + subsidence) compared to a baseline condition (Year 2009). Model results showed that the large-scale diversion had a stronger negative impact on oyster population dynamics via freshening of the entire estuary, resulting in reduced oyster growth rate and production than RSLR. Under the large-scale diversion, areas with optimal oyster growth rates (>15 mg ash-free dry weight (AFDW) oyster−1 wk−1) and production (>500 g AFDW m−2 yr−1) would shift seaward to the southeastern edge of the estuary, turning the estuary into a very low oyster production system. RSLR however played a greater role than the small-scale diversion on the magnitude and spatial pattern of oyster growth rate and production. RSLR would result in an overall estuary-wide decrease in oyster growth rate and production as a

  14. Sample-size dependence of diversity indices and the determination of sufficient sample size in a high-diversity deep-sea environment

    OpenAIRE

    Soetaert, K.; Heip, C.H.R.

    1990-01-01

    Diversity indices, although designed for comparative purposes, often cannot be used as such, due to their sample-size dependence. It is argued here that this dependence is more pronounced in high diversity than in low diversity assemblages and that indices more sensitive to rarer species require larger sample sizes to estimate diversity with reasonable precision than indices which put more weight on commoner species. This was tested for Hill's diversity number N sub(0) to N sub( proportional ...

  15. Genome-Based Studies of Marine Microorganisms to Maximize the Diversity of Natural Products Discovery for Medical Treatments

    Directory of Open Access Journals (Sweden)

    Xin-Qing Zhao

    2011-01-01

    Full Text Available Marine microorganisms are rich source for natural products which play important roles in pharmaceutical industry. Over the past decade, genome-based studies of marine microorganisms have unveiled the tremendous diversity of the producers of natural products and also contributed to the efficiency of harness the strain diversity and chemical diversity, as well as the genetic diversity of marine microorganisms for the rapid discovery and generation of new natural products. In the meantime, genomic information retrieved from marine symbiotic microorganisms can also be employed for the discovery of new medical molecules from yet-unculturable microorganisms. In this paper, the recent progress in the genomic research of marine microorganisms is reviewed; new tools of genome mining as well as the advance in the activation of orphan pathways and metagenomic studies are summarized. Genome-based research of marine microorganisms will maximize the biodiscovery process and solve the problems of supply and sustainability of drug molecules for medical treatments.

  16. High throughput screening and profiling of high-value carotenoids from a wide diversity of bacteria in surface seawater.

    Science.gov (United States)

    Asker, Dalal

    2018-09-30

    Carotenoids are valuable natural colorants that exhibit numerous health promoting properties, and thus are widely used in food, feeds, pharmaceutical and nutraceuticals industries. In this study, we isolated and identified novel microbial sources that produced high-value carotenoids using high throughput screening (HTS). A total of 701 pigmented microbial strains library including marine bacteria and red yeast was constructed. Carotenoids profiling using HPLC-DAD-MS methods showed 88 marine bacterial strains with potential for the production of high-value carotenoids including astaxanthin (28 strains), zeaxanthin (21 strains), lutein (1 strains) and canthaxanthin (2 strains). A comprehensive 16S rRNA gene based phylogenetic analysis revealed that these strains can be classified into 30 species belonging to five bacterial classes (Flavobacteriia, α-Proteobacteria, γ-Proteobacteria, Actinobacteria and Bacilli). Importantly, we discovered novel producers of zeaxanthin and lutein, and a high diversity in both carotenoids and producing microbial strains, which are promising and highly selective biotechnological sources for high-value carotenoids. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Root interactions in a diverse grassland : the role of root traits in belowground productivity and decomposition

    NARCIS (Netherlands)

    Oram, Natalie J.

    2018-01-01

    Background Plant diversity influences ecosystem functioning. A positive relation between plant diversity and productivity above- and belowground has been established. Aboveground, this effect has been shown to be due to complementarity effects, interactions between species in a mixture

  18. Long-term organic-inorganic fertilization ensures great soil productivity and bacterial diversity after natural-to-agricultural ecosystem conversion.

    Science.gov (United States)

    Xun, Weibing; Xu, Zhihui; Li, Wei; Ren, Yi; Huang, Ting; Ran, Wei; Wang, Boren; Shen, Qirong; Zhang, Ruifu

    2016-09-01

    Natural ecosystems comprise the planet's wild plant and animal resources, but large tracts of land have been converted to agroecosystems to support the demand for agricultural products. This conversion limits the number of plant species and decreases the soil biological diversity. Here we used high-throughput 16S rRNA gene sequencing to evaluate the responses of soil bacterial communities in long-term converted and fertilized red soils (a type of Ferralic Cambisol). We observed that soil bacterial diversity was strongly affected by different types of fertilization management. Oligotrophic bacterial taxa demonstrated large relative abundances in chemically fertilized soil, whereas copiotrophic bacterial taxa were found in large relative abundances in organically fertilized and fallow management soils. Only organic-inorganic fertilization exhibited the same local taxonomic and phylogenetic diversity as that of a natural ecosystem. However, the independent use of organic or inorganic fertilizer reduced local taxonomic and phylogenetic diversity and caused biotic homogenization. This study demonstrated that the homogenization of bacterial communities caused by natural-to-agricultural ecosystem conversion can be mitigated by employing rational organic-inorganic fertilization management.

  19. Flower diversity and bee reproduction in an arid ecosystem

    OpenAIRE

    Dorado, Jimena; V?zquez, Diego P.

    2016-01-01

    Background: Diverse flower communities are more stable in floral resource production along the flowering season, but the question about how the diversity and stability of resources affect pollinator reproduction remains open. High plant diversity could favor short foraging trips, which in turn would enhance bee fitness. In addition to plant diversity, greater temporal stability of floral resources in diverse communities could favor pollinator fitness because such communities are likely to occ...

  20. Genes associated to lactose metabolism illustrate the high diversity of Carnobacterium maltaromaticum

    DEFF Research Database (Denmark)

    Iskandar, Christelle F.; Cailliez-Grimal, Catherine; Rahman, Abdur

    2016-01-01

    The dairy population of Carnobacterium maltaromaticum is characterized by a high diversity suggesting a high diversity of the genetic traits linked to the dairy process. As lactose is the main carbon source in milk, the genetics of lactose metabolism was investigated in this LAB. Comparative...

  1. Development of independent production in Europe: institutional diversity

    International Nuclear Information System (INIS)

    Krause, G.G.

    1995-01-01

    The industrial model of the power sector is being challenged in all but a few countries. Being stable for many years, the power sector is now constrained to evolve to more flexible structures, pushed by financing, political and environmental issues. More so, recent innovations within the financing or entrepreneurial background, as well as in the main equipment suppliers' strategies, have attracted new actors to a formerly closed sector. The independent power production could be seen as a vector leading sector's reforms in several countries, being recognized an a careful path, a way to gradually opening the sector. The analysis of the institutional structures within which the independent production evolves can point out relevant elements and directions of sector's changes. One can find, for instances, within a relatively restraint universe, i.e. that one of the European countries, a variety of situations putting light on the complexity of the debate. This paper aims at discussing the role of the independent power production through such a diversity of institutional structures, avoiding any polarization around themes like privatization or deregulation. (author). 1 fig., 2 tabs., 13 refs

  2. MANAGING HIGH-END, HIGH-VOLUME INNOVATIVE PRODUCTS

    Directory of Open Access Journals (Sweden)

    Gembong Baskoro

    2008-01-01

    Full Text Available This paper discuses the concept of managing high-end, high-volume innovative products. High-end, high-volume consumer products are products that have considerable influence to the way of life. Characteristic of High-end, high-volume consumer products are (1 short cycle time, (2 quick obsolete time, and (3 rapid price erosion. Beside the disadvantages that they are high risk for manufacturers, if manufacturers are able to understand precisely the consumer needs then they have the potential benefit or success to be the market leader. High innovation implies to high utilization of the user, therefore these products can influence indirectly to the way of people life. The objective of managing them is to achieve sustainability of the products development and innovation. This paper observes the behavior of these products in companies operated in high-end, high-volume consumer product.

  3. Leaf bacterial diversity mediates plant diversity and ecosystem function relationships.

    Science.gov (United States)

    Laforest-Lapointe, Isabelle; Paquette, Alain; Messier, Christian; Kembel, Steven W

    2017-06-01

    Research on biodiversity and ecosystem functioning has demonstrated links between plant diversity and ecosystem functions such as productivity. At other trophic levels, the plant microbiome has been shown to influence host plant fitness and function, and host-associated microbes have been proposed to influence ecosystem function through their role in defining the extended phenotype of host organisms However, the importance of the plant microbiome for ecosystem function has not been quantified in the context of the known importance of plant diversity and traits. Here, using a tree biodiversity-ecosystem functioning experiment, we provide strong support for the hypothesis that leaf bacterial diversity is positively linked to ecosystem productivity, even after accounting for the role of plant diversity. Our results also show that host species identity, functional identity and functional diversity are the main determinants of leaf bacterial community structure and diversity. Our study provides evidence of a positive correlation between plant-associated microbial diversity and terrestrial ecosystem productivity, and a new mechanism by which models of biodiversity-ecosystem functioning relationships can be improved.

  4. Rare species support vulnerable functions in high-diversity ecosystems.

    Science.gov (United States)

    Mouillot, David; Bellwood, David R; Baraloto, Christopher; Chave, Jerome; Galzin, Rene; Harmelin-Vivien, Mireille; Kulbicki, Michel; Lavergne, Sebastien; Lavorel, Sandra; Mouquet, Nicolas; Paine, C E Timothy; Renaud, Julien; Thuiller, Wilfried

    2013-01-01

    Around the world, the human-induced collapses of populations and species have triggered a sixth mass extinction crisis, with rare species often being the first to disappear. Although the role of species diversity in the maintenance of ecosystem processes has been widely investigated, the role of rare species remains controversial. A critical issue is whether common species insure against the loss of functions supported by rare species. This issue is even more critical in species-rich ecosystems where high functional redundancy among species is likely and where it is thus often assumed that ecosystem functioning is buffered against species loss. Here, using extensive datasets of species occurrences and functional traits from three highly diverse ecosystems (846 coral reef fishes, 2,979 alpine plants, and 662 tropical trees), we demonstrate that the most distinct combinations of traits are supported predominantly by rare species both in terms of local abundance and regional occupancy. Moreover, species that have low functional redundancy and are likely to support the most vulnerable functions, with no other species carrying similar combinations of traits, are rarer than expected by chance in all three ecosystems. For instance, 63% and 98% of fish species that are likely to support highly vulnerable functions in coral reef ecosystems are locally and regionally rare, respectively. For alpine plants, 32% and 89% of such species are locally and regionally rare, respectively. Remarkably, 47% of fish species and 55% of tropical tree species that are likely to support highly vulnerable functions have only one individual per sample on average. Our results emphasize the importance of rare species conservation, even in highly diverse ecosystems, which are thought to exhibit high functional redundancy. Rare species offer more than aesthetic, cultural, or taxonomic diversity value; they disproportionately increase the potential breadth of functions provided by ecosystems across

  5. Cyanobacteria as a Platform for the High-Value Chemicals Production

    DEFF Research Database (Denmark)

    Wlodarczyk, Artur Jacek

    and cheap fertilizer as a medium for the cultivation of engineered cyanobacterial strains is shown. Alternative strategy to engineer Synechocystis sp. PCC 6803 as a universal platform for the sustainable production of diverse range high-value phenylpropanoids which find use as pharmaceuticals, cosmetics......Emerging problems like increasing global warming and depletion of fossil fuels bring serious concerns regarding production of food and various chemicals in the future. Clearly, there is a need for finding alternative and more sustainable ways of producing chemicals in order to satisfy increasing...... consumer demands of an ever growing population. Considering the ability to convert solar energy and carbon dioxide into biomass, cyanobacteria and microalgae have potential for becoming such alternative in the future. Biosynthesis of a great number of plant high-value secondary metabolites requires...

  6. Twenty-million-year relationship between mammalian diversity and primary productivity

    Science.gov (United States)

    Fritz, Susanne A.; Eronen, Jussi T.; Schnitzler, Jan; Hof, Christian; Janis, Christine M.; Mulch, Andreas; Böhning-Gaese, Katrin; Graham, Catherine H.

    2016-01-01

    At global and regional scales, primary productivity strongly correlates with richness patterns of extant animals across space, suggesting that resource availability and climatic conditions drive patterns of diversity. However, the existence and consistency of such diversity–productivity relationships through geological history is unclear. Here we provide a comprehensive quantitative test of the diversity–productivity relationship for terrestrial large mammals through time across broad temporal and spatial scales. We combine >14,000 occurrences for 690 fossil genera through the Neogene (23–1.8 Mya) with regional estimates of primary productivity from fossil plant communities in North America and Europe. We show a significant positive diversity–productivity relationship through the 20-million-year record, providing evidence on unprecedented spatial and temporal scales that this relationship is a general pattern in the ecology and paleo-ecology of our planet. Further, we discover that genus richness today does not match the fossil relationship, suggesting that a combination of human impacts and Pleistocene climate variability has modified the 20-million-year ecological relationship by strongly reducing primary productivity and driving many mammalian species into decline or to extinction. PMID:27621451

  7. Heat integration in processes with diverse production lines: A comprehensive framework and an application in food industry

    International Nuclear Information System (INIS)

    Miah, J.H.; Griffiths, A.; McNeill, R.; Poonaji, I.; Martin, R.; Yang, A.; Morse, S.

    2014-01-01

    Highlights: • A new practical heat integration framework was developed for complex and diverse production lines. • Heat recovery was maximised by direct and indirect heat integration at zonal and factory levels. • A novel approach to stream data extraction was proposed to account for both stream capacity and availability. • A case study was carried out on a multi-product confectionery factory. - Abstract: Heat integration is a key measure to improving energy efficiency and maximising heat recovery. Since the advent of Pinch analysis in the 1980s, direct and indirect integration approaches have developed in separate domains with very few examples where both approaches are utilised together to maximise heat recovery. This paper presents a novel decision-making framework for heat integration in complex and diverse production lines, with the aim to provide the user with a step-by-step guide to evaluate all heat recovery opportunities through a combination of direct and indirect heat integration. This framework involves analysis at both the zonal level and the factory level. The proposed framework was applied to a case study based on a confectionery factory in the UK that manufactured multiple products across a diverse range of food technologies. It demonstrates that the framework can effectively identify the significant streams to be considered in the heat integration analysis, and address practical factors such as diverse production times, geographical proximity, and potential of compromise to product quality when the direct and indirect heat integration opportunities are proposed and assessed both within and between production zones. This practical framework has the potential to benefit the wider food industry and beyond

  8. Knowledge Production beyond Local and National Blindspots: Remedying Professional Ocularcentrism of Diversity in Music Teacher Education

    Science.gov (United States)

    Westerlund, Heidi; Karlsen, Sidsel

    2017-01-01

    In this article, we argue that mainstream discourses of diversity in music education are ocularcentric; that is, they provide a one-sided way of understanding diversity that has prevented music educators from seeing our biases. In remedying these local and national professional blindspots, we propose transnational knowledge production, which we…

  9. Primary production and algae diversity vs. pollution in xochimilco wet-lands

    Energy Technology Data Exchange (ETDEWEB)

    Pedroza-Pichardo, R.; Hernandez-Delgadillo, R.; Boll-Arguello, G.

    2009-07-01

    Xochimilco is an ancient endorheic lake located in the Valley of Mexico. Due to its shallow water and the freshwater springs that lined the canals, they are surround raised agricultural fields called chinampas. Since the Valley of Mexico was originally wetlands, the chinampas were the most productive means of agricultural production. Xochimilco are considered one of the most important urban lungs in Mexico City. However, it is not clear how the huge urbanization around is to know if there is a correlation between primary production (PP), algae diversity, BOD{sub 5} and faecal coliforms. Sample collection was done every month over a year at six different canals named: Embarcadero Celada, Embarcadero Nuevo Nativitas, Canal Las Abejas, Canal Zacapa, Canal Santo Domingo y Canal Nacional. (Author)

  10. Primary production and algae diversity vs. pollution in xochimilco wet-lands

    International Nuclear Information System (INIS)

    Pedroza-Pichardo, R.; Hernandez-Delgadillo, R.; Boll-Arguello, G.

    2009-01-01

    Xochimilco is an ancient endorheic lake located in the Valley of Mexico. Due to its shallow water and the freshwater springs that lined the canals, they are surround raised agricultural fields called chinampas. Since the Valley of Mexico was originally wetlands, the chinampas were the most productive means of agricultural production. Xochimilco are considered one of the most important urban lungs in Mexico City. However, it is not clear how the huge urbanization around is to know if there is a correlation between primary production (PP), algae diversity, BOD 5 and faecal coliforms. Sample collection was done every month over a year at six different canals named: Embarcadero Celada, Embarcadero Nuevo Nativitas, Canal Las Abejas, Canal Zacapa, Canal Santo Domingo y Canal Nacional. (Author)

  11. Global patterns of workplace productivity for people with depression: absenteeism and presenteeism costs across eight diverse countries.

    Science.gov (United States)

    Evans-Lacko, S; Knapp, M

    2016-11-01

    Depression is a leading cause of disability worldwide. Research suggests that by far, the greatest contributor to the overall economic impact of depression is loss in productivity; however, there is very little research on the costs of depression outside of Western high-income countries. Thus, this study examines the impact of depression on workplace productivity across eight diverse countries. We estimated the extent and costs of depression-related absenteeism and presenteeism in the workplace across eight countries: Brazil, Canada, China, Japan, South Korea, Mexico, South Africa, and the USA. We also examined the individual, workplace, and societal factors associated with lower productivity. To the best of our knowledge, this is the first study to examine the impact of depression on workplace productivity across a diverse set of countries, in terms of both culture and GDP. Mean annual per person costs for absenteeism were lowest in South Korea at $181 and highest in Japan ($2674). Mean presenteeism costs per person were highest in the USA ($5524) and Brazil ($5788). Costs associated with presenteeism tended to be 5-10 times higher than those associated with absenteeism. These findings suggest that the impact of depression in the workplace is considerable across all countries, both in absolute monetary terms and in relation to proportion of country GDP. Overall, depression is an issue deserving much greater attention, regardless of a country's economic development, national income or culture.

  12. Genetic diversity analysis of Leuconostoc mesenteroides from Korean vegetables and food products by multilocus sequence typing.

    Science.gov (United States)

    Sharma, Anshul; Kaur, Jasmine; Lee, Sulhee; Park, Young-Seo

    2018-06-01

    In the present study, 35 Leuconostoc mesenteroides strains isolated from vegetables and food products from South Korea were studied by multilocus sequence typing (MLST) of seven housekeeping genes (atpA, groEL, gyrB, pheS, pyrG, rpoA, and uvrC). The fragment sizes of the seven amplified housekeeping genes ranged in length from 366 to 1414 bp. Sequence analysis indicated 27 different sequence types (STs) with 25 of them being represented by a single strain indicating high genetic diversity, whereas the remaining 2 were characterized by five strains each. In total, 220 polymorphic nucleotide sites were detected among seven housekeeping genes. The phylogenetic analysis based on the STs of the seven loci indicated that the 35 strains belonged to two major groups, A (28 strains) and B (7 strains). Split decomposition analysis showed that intraspecies recombination played a role in generating diversity among strains. The minimum spanning tree showed that the evolution of the STs was not correlated with food source. This study signifies that the multilocus sequence typing is a valuable tool to access the genetic diversity among L. mesenteroides strains from South Korea and can be used further to monitor the evolutionary changes.

  13. Local endemicity and high diversity characterise high-latitude coral- Symbiodinium partnerships

    Science.gov (United States)

    Wicks, L. C.; Sampayo, E.; Gardner, J. P. A.; Davy, S. K.

    2010-12-01

    Obligate symbiotic dinoflagellates ( Symbiodinium) residing within the tissues of most reef invertebrates are important in determining the tolerance range of their host. Coral communities living at high latitudes experience wide fluctuations in environmental conditions and thus provide an ideal system to gain insights into the range within which the symbiotic relationship can be sustained. Further, understanding whether and how symbiont communities associated with high-latitude coral reefs are different from their tropical counterparts will provide clues to the potential of corals to cope with marginal or changing conditions. However, little is known of the host and symbiont partnerships at high latitudes. Symbiodinium diversity and specificity of high-latitude coral communities were explored using denaturing gradient gel electrophoresis (PCR-DGGE) analysis of the internal transcribed spacer regions (ITS1 and ITS2) of the ribosomal DNA at Lord Howe Island (31°S; Australia), and the Kermadec Islands (29°S; New Zealand). All but one host associated with clade C Symbiodinium, the exception being a soft coral ( Capnella sp.) that contained Symbiodinium B1. Besides ‘host-generalist’ Symbiodinium types C1 and C3, approximately 72% of the Symbiodinium identified were novel C types, and zonation of symbionts in relation to environmental parameters such as depth and turbidity was evident in certain host species. The high-latitude Symbiodinium communities showed little overlap and relatively high diversity compared with communities sampled on the tropical Great Barrier Reef. Although host specificity was maintained in certain species, others shared symbionts and this potential reduction of fidelity at high-latitude locations may be the result of locally challenging and highly variable environmental conditions.

  14. Diversity and Composition of Sulfate-Reducing Microbial Communities Based on Genomic DNA and RNA Transcription in Production Water of High Temperature and Corrosive Oil Reservoir

    Directory of Open Access Journals (Sweden)

    Xiao-Xiao Li

    2017-06-01

    Full Text Available Deep subsurface petroleum reservoir ecosystems harbor a high diversity of microorganisms, and microbial influenced corrosion is a major problem for the petroleum industry. Here, we used high-throughput sequencing to explore the microbial communities based on genomic 16S rDNA and metabolically active 16S rRNA analyses of production water samples with different extents of corrosion from a high-temperature oil reservoir. Results showed that Desulfotignum and Roseovarius were the most abundant genera in both genomic and active bacterial communities of all the samples. Both genomic and active archaeal communities were mainly composed of Archaeoglobus and Methanolobus. Within both bacteria and archaea, the active and genomic communities were compositionally distinct from one another across the different oil wells (bacteria p = 0.002; archaea p = 0.01. In addition, the sulfate-reducing microorganisms (SRMs were specifically assessed by Sanger sequencing of functional genes aprA and dsrA encoding the enzymes adenosine-5′-phosphosulfate reductase and dissimilatory sulfite reductase, respectively. Functional gene analysis indicated that potentially active Archaeoglobus, Desulfotignum, Desulfovibrio, and Thermodesulforhabdus were frequently detected, with Archaeoglobus as the most abundant and active sulfate-reducing group. Canonical correspondence analysis revealed that the SRM communities in petroleum reservoir system were closely related to pH of the production water and sulfate concentration. This study highlights the importance of distinguishing the metabolically active microorganisms from the genomic community and extends our knowledge on the active SRM communities in corrosive petroleum reservoirs.

  15. Diversity and Composition of Sulfate-Reducing Microbial Communities Based on Genomic DNA and RNA Transcription in Production Water of High Temperature and Corrosive Oil Reservoir

    Science.gov (United States)

    Li, Xiao-Xiao; Liu, Jin-Feng; Zhou, Lei; Mbadinga, Serge M.; Yang, Shi-Zhong; Gu, Ji-Dong; Mu, Bo-Zhong

    2017-01-01

    Deep subsurface petroleum reservoir ecosystems harbor a high diversity of microorganisms, and microbial influenced corrosion is a major problem for the petroleum industry. Here, we used high-throughput sequencing to explore the microbial communities based on genomic 16S rDNA and metabolically active 16S rRNA analyses of production water samples with different extents of corrosion from a high-temperature oil reservoir. Results showed that Desulfotignum and Roseovarius were the most abundant genera in both genomic and active bacterial communities of all the samples. Both genomic and active archaeal communities were mainly composed of Archaeoglobus and Methanolobus. Within both bacteria and archaea, the active and genomic communities were compositionally distinct from one another across the different oil wells (bacteria p = 0.002; archaea p = 0.01). In addition, the sulfate-reducing microorganisms (SRMs) were specifically assessed by Sanger sequencing of functional genes aprA and dsrA encoding the enzymes adenosine-5′-phosphosulfate reductase and dissimilatory sulfite reductase, respectively. Functional gene analysis indicated that potentially active Archaeoglobus, Desulfotignum, Desulfovibrio, and Thermodesulforhabdus were frequently detected, with Archaeoglobus as the most abundant and active sulfate-reducing group. Canonical correspondence analysis revealed that the SRM communities in petroleum reservoir system were closely related to pH of the production water and sulfate concentration. This study highlights the importance of distinguishing the metabolically active microorganisms from the genomic community and extends our knowledge on the active SRM communities in corrosive petroleum reservoirs. PMID:28638372

  16. Global gradients in vertebrate diversity predicted by historical area-productivity dynamics and contemporary environment.

    Directory of Open Access Journals (Sweden)

    Walter Jetz

    Full Text Available Broad-scale geographic gradients in species richness have now been extensively documented, but their historical underpinning is still not well understood. While the importance of productivity, temperature, and a scale dependence of the determinants of diversity is broadly acknowledged, we argue here that limitation to a single analysis scale and data pseudo-replication have impeded an integrated evolutionary and ecological understanding of diversity gradients. We develop and apply a hierarchical analysis framework for global diversity gradients that incorporates an explicit accounting of past environmental variation and provides an appropriate measurement of richness. Due to environmental niche conservatism, organisms generally reside in climatically defined bioregions, or "evolutionary arenas," characterized by in situ speciation and extinction. These bioregions differ in age and their total productivity and have varied over time in area and energy available for diversification. We show that, consistently across the four major terrestrial vertebrate groups, current-day species richness of the world's main 32 bioregions is best explained by a model that integrates area and productivity over geological time together with temperature. Adding finer scale variation in energy availability as an ecological predictor of within-bioregional patterns of richness explains much of the remaining global variation in richness at the 110 km grain. These results highlight the separate evolutionary and ecological effects of energy availability and provide a first conceptual and empirical integration of the key drivers of broad-scale richness gradients. Avoiding the pseudo-replication that hampers the evolutionary interpretation of non-hierarchical macroecological analyses, our findings integrate evolutionary and ecological mechanisms at their most relevant scales and offer a new synthesis regarding global diversity gradients.

  17. Rare species support vulnerable functions in high-diversity ecosystems.

    Directory of Open Access Journals (Sweden)

    David Mouillot

    Full Text Available Around the world, the human-induced collapses of populations and species have triggered a sixth mass extinction crisis, with rare species often being the first to disappear. Although the role of species diversity in the maintenance of ecosystem processes has been widely investigated, the role of rare species remains controversial. A critical issue is whether common species insure against the loss of functions supported by rare species. This issue is even more critical in species-rich ecosystems where high functional redundancy among species is likely and where it is thus often assumed that ecosystem functioning is buffered against species loss. Here, using extensive datasets of species occurrences and functional traits from three highly diverse ecosystems (846 coral reef fishes, 2,979 alpine plants, and 662 tropical trees, we demonstrate that the most distinct combinations of traits are supported predominantly by rare species both in terms of local abundance and regional occupancy. Moreover, species that have low functional redundancy and are likely to support the most vulnerable functions, with no other species carrying similar combinations of traits, are rarer than expected by chance in all three ecosystems. For instance, 63% and 98% of fish species that are likely to support highly vulnerable functions in coral reef ecosystems are locally and regionally rare, respectively. For alpine plants, 32% and 89% of such species are locally and regionally rare, respectively. Remarkably, 47% of fish species and 55% of tropical tree species that are likely to support highly vulnerable functions have only one individual per sample on average. Our results emphasize the importance of rare species conservation, even in highly diverse ecosystems, which are thought to exhibit high functional redundancy. Rare species offer more than aesthetic, cultural, or taxonomic diversity value; they disproportionately increase the potential breadth of functions provided by

  18. Species Diversity Effects on Productivity, Persistence and Quality of Multispecies Swards in a Four-Year Experiment

    DEFF Research Database (Denmark)

    Jing, Jingying; Søegaard, Karen; Cong, Wen-Feng

    2017-01-01

    ), neutral detergent fiber (NDF) and crude protein (CP), and a lower concentration of ash than the 10-mix and 12-mix. Slurry application increased annual yield production by 10% and changed the botanical composition, increasing the proportion of grass and decreasing the proportion of legumes. Compared......Plant species diversity may benefit natural grassland productivity, but its effect in managed grassland systems is not well understood. A four-year multispecies grassland experiment was conducted to investigate the effect of species diversity±legumes and non-leguminous forbs±on productivity...... increased sward production and yield persistence under cutting regime. The 12-mix had the highest yield from the second year onwards and no statistically significant yield reduction over four years, while annual yields in the 3-mix and 10-mix decreased significantly with increasing grassland age. The higher...

  19. Microsatellite markers suggest high genetic diversity in an urban ...

    Indian Academy of Sciences (India)

    FRANCISCO MORINHA

    diversity in an urban population of Cooper's hawks (Accipiter cooperii). J. Genet. 95, e19–e24. ... high quality habitat for this species (Boggie and Mannan. 2014) and the rapid ... The high densities of birds in urban populations can result in the ..... comparing urban and rural Cooper's hawk populations are mandatory to ...

  20. Resistome diversity in cattle and the environment decreases during beef production.

    Science.gov (United States)

    Noyes, Noelle R; Yang, Xiang; Linke, Lyndsey M; Magnuson, Roberta J; Dettenwanger, Adam; Cook, Shaun; Geornaras, Ifigenia; Woerner, Dale E; Gow, Sheryl P; McAllister, Tim A; Yang, Hua; Ruiz, Jaime; Jones, Kenneth L; Boucher, Christina A; Morley, Paul S; Belk, Keith E

    2016-03-08

    Antimicrobial resistant determinants (ARDs) can be transmitted from livestock systems through meat products or environmental effluents. The public health risk posed by these two routes is not well understood, particularly in non-pathogenic bacteria. We collected pooled samples from 8 groups of 1741 commercial cattle as they moved through the process of beef production from feedlot entry through slaughter. We recorded antimicrobial drug exposures and interrogated the resistome at points in production when management procedures could potentially influence ARD abundance and/or transmission. Over 300 unique ARDs were identified. Resistome diversity decreased while cattle were in the feedlot, indicating selective pressure. ARDs were not identified in beef products, suggesting that slaughter interventions may reduce the risk of transmission of ARDs to beef consumers. This report highlights the utility and limitations of metagenomics for assessing public health risks regarding antimicrobial resistance, and demonstrates that environmental pathways may represent a greater risk than the food supply.

  1. Diversity effects on root length production and loss in an experimental grassland community

    NARCIS (Netherlands)

    Mommer, L.; Padilla, F.M.; Ruijven, van J.; Caluwe, de H.; Smit-Tiekstra, A.E.; Berendse, F.; Kroon, de H.

    2015-01-01

    Advances in root ecology have revealed that root standing biomass is higher in species-rich plant communities than in species-poor communities. Currently, we do not know whether this below-ground diversity effect is the result of enhanced root production or reduced root mortality or both, which is

  2. Genomic Diversity of Lactobacillus salivarius▿ †

    Science.gov (United States)

    Raftis, Emma J.; Salvetti, Elisa; Torriani, Sandra; Felis, Giovanna E.; O'Toole, Paul W.

    2011-01-01

    Strains of Lactobacillus salivarius are increasingly employed as probiotic agents for humans or animals. Despite the diversity of environmental sources from which they have been isolated, the genomic diversity of L. salivarius has been poorly characterized, and the implications of this diversity for strain selection have not been examined. To tackle this, we applied comparative genomic hybridization (CGH) and multilocus sequence typing (MLST) to 33 strains derived from humans, animals, or food. The CGH, based on total genome content, including small plasmids, identified 18 major regions of genomic variation, or hot spots for variation. Three major divisions were thus identified, with only a subset of the human isolates constituting an ecologically discernible group. Omission of the small plasmids from the CGH or analysis by MLST provided broadly concordant fine divisions and separated human-derived and animal-derived strains more clearly. The two gene clusters for exopolysaccharide (EPS) biosynthesis corresponded to regions of significant genomic diversity. The CGH-based groupings of these regions did not correlate with levels of production of bound or released EPS. Furthermore, EPS production was significantly modulated by available carbohydrate. In addition to proving difficult to predict from the gene content, EPS production levels correlated inversely with production of biofilms, a trait considered desirable in probiotic commensals. L. salivarius displays a high level of genomic diversity, and while selection of L. salivarius strains for probiotic use can be informed by CGH or MLST, it also requires pragmatic experimental validation of desired phenotypic traits. PMID:21131523

  3. Microfluidics without channels: highly-flexible synthesis on a digital-microfluidic chip for production of diverse PET tracers

    Energy Technology Data Exchange (ETDEWEB)

    Van Dam, Robert Michael [Univ. of California, Los Angeles, CA (United States)

    2010-09-01

    Positron emission tomography (PET) imaging is used for fundamental studies of living biological organisms and microbial ecosystems in applications ranging from biofuel production to environmental remediation to the study, diagnosis, and treatment monitoring of human disease. Routine access to PET imaging, to monitor biochemical reactions in living organisms in real time, could accelerate a broad range of research programs of interest to DOE. Using PET requires access to short-lived radioactive-labeled compounds that specifically probe the desired living processes. The overall aims of this project were to develop a miniature liquid-handling technology platform (called “microfluidics”) that increases the availability of diverse PET probes by reducing the cost and complexity of their production. Based on preliminary experiments showing that microfluidic chips can synthesis such compounds, we aimed to advance this technology to improve its robustness, increase its flexibility for a broad range of probes, and increase its user-friendliness. Through the research activities of this project, numerous advances were made; Tools were developed to enable the visualization of radioactive materials within microfluidic chips; Fundamental advances were made in the microfluidic chip architecture and fabrication process to increase its robustness and reliability; The microfluidic chip technology was shown to produce useful quantities of an example PET probes, and methods to further increase the output were successfully pursued; A “universal” chip was developed that could produce multiple types of PET probes, enabling the possibility of “on demand” synthesis of different probes; and Operation of the chip was automated to ensure minimal radiation exposure to the operator Based on the demonstrations of promising technical feasibility and performance, the microfluidic chip technology is currently being commercialized. It is anticipated that costs of microfluidic chips can be

  4. Plathelminth abundance in North Sea salt marshes: environmental instability causes high diversity

    Science.gov (United States)

    Armonies, Werner

    1986-09-01

    Although supralittoral salt marshes are habitats of high environmental instability, the meiofauna is rich in species and abundance is high. The community structure of free-living Plathelminthes (Turbellaria) in these salt marshes is described. On an average, 104 individuals are found below an area of 10 cm2. The average species density in ungrazed salt marshes is 11.3 below 10 cm2 and 45.2 below 100 cm2, indicating strong small-scale heterogenity. The faunal similarity between sediment and the corresponding above-ground vegetation is higher than between adjacent sample sites. Species prefer distinct ranges of salinity. In the lower part of the supralittoral salt marshes, the annual fluctuations of salinity are strongest and highly unpredictable. This region is richest in plathelminth species and abundance; diversity is highest, and the faunal composition of parallel samples is quite similar. In the upper part of the supralittoral salt marshes, the annual variability of salinity is lower, plathelminths are poor in species diversity and abundance. Parallel samples often have no species in common. Thus, those salt marsh regions with the most unstable environment are inhabited by the most diverse species assemblage. Compared to other littoral zones of the North Sea, however, plathelminth diversity in salt marshes is low. The observed plathelminth diversity pattern can apparently be explained by the “dynamic equilibrium model” (Huston, 1979).

  5. Experimental analysis of specification language diversity impact on NPP software diversity

    International Nuclear Information System (INIS)

    Yoo, Chang Sik

    1999-02-01

    In order to increase computer system reliability, software fault tolerance methods have been adopted to some safety critical systems including NPP. Prevention of software common mode failure is very crucial problem in software fault tolerance, but the effective method for this problem is not found yet. In our research, to find out an effective method for prevention of software common mode failure, the impact of specification language diversity on NPP software diversity was examined experimentally. Three specification languages were used to compose three requirements specifications, and programmers made twelve product codes from the specifications. From the product codes analysis, using fault diversity criteria, we concluded that diverse specification language method would enhance program diversity through diversification of requirements specification imperfections

  6. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae) outbreak in pine forests.

    Science.gov (United States)

    Pec, Gregory J; Karst, Justine; Sywenky, Alexandra N; Cigan, Paul W; Erbilgin, Nadir; Simard, Suzanne W; Cahill, James F

    2015-01-01

    The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae) in lodgepole pine (Pinus contorta) forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  7. Rapid Increases in forest understory diversity and productivity following a mountain pine beetle (Dendroctonus ponderosae outbreak in pine forests.

    Directory of Open Access Journals (Sweden)

    Gregory J Pec

    Full Text Available The current unprecedented outbreak of mountain pine beetle (Dendroctonus ponderosae in lodgepole pine (Pinus contorta forests of western Canada has resulted in a landscape consisting of a mosaic of forest stands at different stages of mortality. Within forest stands, understory communities are the reservoir of the majority of plant species diversity and influence the composition of future forests in response to disturbance. Although changes to stand composition following beetle outbreaks are well documented, information on immediate responses of forest understory plant communities is limited. The objective of this study was to examine the effects of D. ponderosae-induced tree mortality on initial changes in diversity and productivity of understory plant communities. We established a total of 110 1-m2 plots across eleven mature lodgepole pine forests to measure changes in understory diversity and productivity as a function of tree mortality and below ground resource availability across multiple years. Overall, understory community diversity and productivity increased across the gradient of increased tree mortality. Richness of herbaceous perennials increased with tree mortality as well as soil moisture and nutrient levels. In contrast, the diversity of woody perennials did not change across the gradient of tree mortality. Understory vegetation, namely herbaceous perennials, showed an immediate response to improved growing conditions caused by increases in tree mortality. How this increased pulse in understory richness and productivity affects future forest trajectories in a novel system is unknown.

  8. Flower diversity and bee reproduction in an arid ecosystem

    Directory of Open Access Journals (Sweden)

    Jimena Dorado

    2016-07-01

    Full Text Available Background: Diverse flower communities are more stable in floral resource production along the flowering season, but the question about how the diversity and stability of resources affect pollinator reproduction remains open. High plant diversity could favor short foraging trips, which in turn would enhance bee fitness. In addition to plant diversity, greater temporal stability of floral resources in diverse communities could favor pollinator fitness because such communities are likely to occupy the phenological space more broadly, increasing floral availability for pollinators throughout the season. In addition, this potential effect of flower diversity on bee reproduction could be stronger for generalist pollinators because they can use a broader floral spectrum. Based on above arguments we predicted that pollinator reproduction would be positively correlated to flower diversity, and to temporal stability in flower production, and that this relationship would be stronger for the most generalized pollinator species. Materials and Methods: Using structural equation models, we evaluated the effect of these variables and other ecological factors on three estimates of bee reproduction (average number of brood cells per nest per site, total number of brood cells per site, and total number of nests per site, and whether such effects were modulated by bee generalization on floral resources. Results: Contrary to our expectations, flower diversity had no effect on bee reproduction, stability in flower production had a weakly negative effect on one of the bee reproductive variables, and the strength of the fitness-diversity relationship was unrelated to bee generalization. In contrast, elevation had a negative effect on bee reproduction, despite the narrow elevation range encompassed by our sites. Discussion: Flower diversity did not affect the reproduction of the solitary bees studied here. This result could stem from the context dependence of the

  9. Flower diversity and bee reproduction in an arid ecosystem.

    Science.gov (United States)

    Dorado, Jimena; Vázquez, Diego P

    2016-01-01

    Diverse flower communities are more stable in floral resource production along the flowering season, but the question about how the diversity and stability of resources affect pollinator reproduction remains open. High plant diversity could favor short foraging trips, which in turn would enhance bee fitness. In addition to plant diversity, greater temporal stability of floral resources in diverse communities could favor pollinator fitness because such communities are likely to occupy the phenological space more broadly, increasing floral availability for pollinators throughout the season. In addition, this potential effect of flower diversity on bee reproduction could be stronger for generalist pollinators because they can use a broader floral spectrum. Based on above arguments we predicted that pollinator reproduction would be positively correlated to flower diversity, and to temporal stability in flower production, and that this relationship would be stronger for the most generalized pollinator species. Using structural equation models, we evaluated the effect of these variables and other ecological factors on three estimates of bee reproduction (average number of brood cells per nest per site, total number of brood cells per site, and total number of nests per site), and whether such effects were modulated by bee generalization on floral resources. Contrary to our expectations, flower diversity had no effect on bee reproduction, stability in flower production had a weakly negative effect on one of the bee reproductive variables, and the strength of the fitness-diversity relationship was unrelated to bee generalization. In contrast, elevation had a negative effect on bee reproduction, despite the narrow elevation range encompassed by our sites. Flower diversity did not affect the reproduction of the solitary bees studied here. This result could stem from the context dependence of the diversity-stability relationship, given that elevation had a positive effect on

  10. Plasmodium vivax merozoite surface protein-3 alpha: a high-resolution marker for genetic diversity studies.

    Science.gov (United States)

    Prajapati, Surendra Kumar; Joshi, Hema; Valecha, Neena

    2010-06-01

    Malaria, an ancient human infectious disease caused by five species of Plasmodium, among them Plasmodium vivax is the most widespread human malaria species and causes huge morbidity to its host. Identification of genetic marker to resolve higher genetic diversity for an ancient origin organism is a crucial task. We have analyzed genetic diversity of P. vivax field isolates using highly polymorphic antigen gene merozoite surface protein-3 alpha (msp-3 alpha) and assessed its suitability as high-resolution genetic marker for population genetic studies. 27 P. vivax field isolates collected during chloroquine therapeutic efficacy study at Chennai were analyzed for genetic diversity. PCR-RFLP was employed to assess the genetic variations using highly polymorphic antigen gene msp-3 alpha. We observed three distinct PCR alleles at msp-3 alpha, and among them allele A showed significantly high frequency (53%, chi2 = 8.22, p = 0.001). PCR-RFLP analysis revealed 14 and 17 distinct RFLP patterns for Hha1 and Alu1 enzymes respectively. Further, RFLP analysis revealed that allele A at msp-3 alpha is more diverse in the population compared with allele B and C. Combining Hha1 and Alu1 RFLP patterns revealed 21 distinct genotypes among 22 isolates reflects higher diversity resolution power of msp-3 alpha in the field isolates. P. vivax isolates from Chennai region revealed substantial amount of genetic diversity and comparison of allelic diversity with other antigen genes and microsatellites suggesting that msp-3 alpha could be a high-resolution marker for genetic diversity studies among P. vivax field isolates.

  11. ISSR marker-assisted genetic diversity analysis of Dioscorea hispida and selection of the best variety for sustainable production.

    Science.gov (United States)

    Nudin, Nur Fatihah Hasan; Ali, Abdul Manaf; Ngah, Norhayati; Mazlan, Nor Zuhailah; Mat, Nashriyah; Ghani, Mohd Noor Abd; Alias, Nadiawati; Zakaria, Abd Jamil; Jahan, Md Sarwar

    2017-08-01

    Plant breeding is a way of selection of a particular individual for the production of the progeny by separating or combining desired characteristics. The objective of this study was to justify different characteristics of Dioscorea hispida (Ubi gadong) varieties using molecular techniques to select the best variety for sustainable production at the farmer's level. A total of 160 germplasms of Ubi gadong were collected from different locations at the Terengganu and Kelantan states of Malaysia. Forty eight (48) out of 160 germplasms were selected as "primary" selection based on yield and other qualitative characters. Selected collections were then grown and maintained for ISSR marker-assisted genetic diversity analysis. Overall plant growth and yield of tubers were also determined. A total of 12 ISSR markers were tested to justify the characteristics of Ubi gadong varieties among which three markers showed polymorphic bands and on average 57.3% polymorphism were observed representing the highest variation among germplasms. The ISSR marker based on UPGMA cluster analysis grouped all 48 D. hispida into 10 vital groups that proved a vast genetic variation among germplasm collections. Therefore, hybridization should be made between two distant populations. The D. hispida is already proved as the highest starch content tuber crops and very rich in vitamins with both micro and macro minerals. Considering all these criteria and results from marker-assisted diversity analysis, accessions that are far apart based on their genetic coefficient (like DH27 and DH71; DH30 and DH70; DH43 and DH62; DH45 and DH61; DH77 and DH61; DH78 and DH57) could be selected as parents for further breeding programs. This will bring about greater diversity, which will lead to high productive index in terms of increase in yield and overall quality and for the ultimate target of sustainable Ubi gadong production. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights

  12. The Biological Diversity and Production of Volatile Organic Compounds by Stem-Inhabiting Endophytic Fungi of Ecuador

    OpenAIRE

    Rundell, Susan; Spakowicz, Daniel; Narváez-Trujillo, Alexandra; Strobel, Scott

    2015-01-01

    Fungal endophytes colonize every major lineage of land plants without causing apparent harm to their hosts. Despite their production of interesting and potentially novel compounds, endophytes—particularly those inhabiting stem tissues—are still a vastly underexplored component of microbial diversity. In this study, we explored the diversity of over 1500 fungal endophyte isolates collected from three Ecuadorian ecosystems: lowland tropical forest, cloud forest, and coastal dry forest. We sough...

  13. High and distinct range-edge genetic diversity despite local bottlenecks.

    Directory of Open Access Journals (Sweden)

    Jorge Assis

    Full Text Available The genetic consequences of living on the edge of distributional ranges have been the subject of a largely unresolved debate. Populations occurring along persistent low latitude ranges (rear-edge are expected to retain high and unique genetic diversity. In contrast, currently less favourable environmental conditions limiting population size at such range-edges may have caused genetic erosion that prevails over past historical effects, with potential consequences on reducing future adaptive capacity. The present study provides an empirical test of whether population declines towards a peripheral range might be reflected on decreasing diversity and increasing population isolation and differentiation. We compare population genetic differentiation and diversity with trends in abundance along a latitudinal gradient towards the peripheral distribution range of Saccorhiza polyschides, a large brown seaweed that is the main structural species of kelp forests in SW Europe. Signatures of recent bottleneck events were also evaluated to determine whether the recently recorded distributional shifts had a negative influence on effective population size. Our findings show decreasing population density and increasing spatial fragmentation and local extinctions towards the southern edge. Genetic data revealed two well supported groups with a central contact zone. As predicted, higher differentiation and signs of bottlenecks were found at the southern edge region. However, a decrease in genetic diversity associated with this pattern was not verified. Surprisingly, genetic diversity increased towards the edge despite bottlenecks and much lower densities, suggesting that extinctions and recolonizations have not strongly reduced diversity or that diversity might have been even higher there in the past, a process of shifting genetic baselines.

  14. Multiple criteria decision-making process to derive consensus desired genetic gains for a dairy cattle breeding objective for diverse production systems.

    Science.gov (United States)

    Kariuki, C M; van Arendonk, J A M; Kahi, A K; Komen, H

    2017-06-01

    Dairy cattle industries contribute to food and nutrition security and are a source of income for numerous households in many developing countries. Selective breeding can enhance efficiency in these industries. Developing dairy industries are characterized by diverse production and marketing systems. In this paper, we use weighted goal aggregating procedure to derive consensus trait preferences for different producer categories and processors. We based the study on the dairy industry in Kenya. The analytic hierarchy process was used to derive individual preferences for milk yield (MY), calving interval (CIN), production lifetime (PLT), mature body weight (MBW), and fat yield (FY). Results show that classical classification of production systems into large-scale and smallholder systems does not capture all differences in trait preferences. These differences became apparent when classification was based on productivity at the individual animal level, with high and low intensity producers and processors as the most important groups. High intensity producers had highest preferences for PLT and MY, whereas low intensity producers had highest preference for CIN and PLT; processors preferred MY and FY the most. The highest disagreements between the groups were observed for FY, PLT, and MY. Individual and group preferences were aggregated into consensus preferences using weighted goal programming. Desired gains were obtained as a product of consensus preferences and percentage genetic gains (G%). These were 2.42, 0.22, 2.51, 0.15, and 0.87 for MY, CIN, PLT, MBW, and FY, respectively. Consensus preferences can be used to derive a single compromise breeding objective for situations where the same genetic resources are used in diverse production and marketing circumstances. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license

  15. Biological potential of microalgae in China for biorefinery-based production of biofuels and high value compounds.

    Science.gov (United States)

    Li, Jingjing; Liu, Ying; Cheng, Jay J; Mos, Michal; Daroch, Maurycy

    2015-12-25

    Microalgae abundance and diversity in China shows promise for identifying suitable strains for developing algal biorefinery. Numerous strains of microalgae have already been assessed as feedstocks for bioethanol and biodiesel production, but commercial scale algal biofuel production is yet to be demonstrated, most likely due to huge energy costs associated with algae cultivation, harvesting and processing. Biorefining, integrated processes for the conversion of biomass into a variety of products, can improve the prospects of microalgal biofuels by combining them with the production of high value co-products. Numerous microalgal strains in China have been identified as producers of various high value by-products with wide application in the medicine, food, and cosmetics industries. This paper reviews microalgae resources in China and their potential in producing liquid biofuels (bioethanol and biodiesel) and high value products in an integrated biorefinery approach. Implementation of a 'high value product first' principle should make the integrated process of fuels and chemicals production economically feasible and will ensure that public and private interest in the development of microalgal biotechnology is maintained. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. High-Throughput Sequencing of Microbial Community Diversity and Dynamics during Douchi Fermentation

    Science.gov (United States)

    Tu, Zong-cai; Wang, Xiao-lan

    2016-01-01

    Douchi is a type of Chinese traditional fermented food that is an important source of protein and is used in flavouring ingredients. The end product is affected by the microbial community present during fermentation, but exactly how microbes influence the fermentation process remains poorly understood. We used an Illumina MiSeq approach to investigate bacterial and fungal community diversity during both douchi-koji making and fermentation. A total of 181,443 high quality bacterial 16S rRNA sequences and 221,059 high quality fungal internal transcribed spacer reads were used for taxonomic classification, revealing eight bacterial and three fungal phyla. Firmicutes, Actinobacteria and Proteobacteria were the dominant bacterial phyla, while Ascomycota and Zygomycota were the dominant fungal phyla. At the genus level, Staphylococcus and Weissella were the dominant bacteria, while Aspergillus and Lichtheimia were the dominant fungi. Principal coordinate analysis showed structural separation between the composition of bacteria in koji making and fermentation. However, multivariate analysis of variance based on unweighted UniFrac distances did identify distinct differences (p fermentation. This is the first investigation to integrate douchi fermentation and koji making and fermentation processes through this technological approach. The results provide insight into the microbiome of the douchi fermentation process, and reveal a structural separation that may be stratified by the environment during the production of this traditional fermented food. PMID:27992473

  17. Limnology and cyanobacterial diversity of high altitude lakes of ...

    Indian Academy of Sciences (India)

    Limnological data of four high altitude lakes from the cold desert region of Himachal Pradesh, India, has been correlated with cyanobacterial diversity. Physico-chemical characteristics and nutrient contents of the studied lakes revealed that Sissu Lake is mesotrophic while Chandra Tal, Suraj Tal and Deepak Tal are ...

  18. High-demand jobs: age-related diversity in work ability?

    NARCIS (Netherlands)

    Sluiter, Judith K.

    2006-01-01

    High-demand jobs include 'specific' job demands that are not preventable with state of the art ergonomics knowledge and may overburden the bodily capacities, safety or health of workers. An interesting question is whether the age of the worker is an important factor in explanations of diversity in

  19. Microbial Species and Functional Diversity in Rice Rhizosphere of High-yield Special Ecological Areas

    Directory of Open Access Journals (Sweden)

    PAN Li-yuan

    2016-11-01

    Full Text Available Taoyuan, Yunnan Province is a special eco-site which keeps the highest yield records of rice cultivation in small planting areas. Soil microbial species and functional diversity were evaluated using cultivation method and BIOLOG ecoplates. The results showed that the microbial community of the high yield region was more abundant, and the total microbial population was 2 times of the control, furthermore, the areas belonged to the healthy "bacteria" soil, which was showed as bacteria > actinomycetes > fungi. Bacteria were the dominant populations in the rhizosphere of high yielding rice field, and the yield formation of rice was not correlated with the depth of soil layers. In order to obtain more species diversity information, Shannon diversity index H, Shannon evenness index E and Simpson index D were analyzed, and the results showed that microbial community diversity and evenness were not the main differences between the high and general yield areas. Then, the functional diversity of soil microbial community was investigated through the average well color development(AWCD and diversity index analyses. The results of AWCD analysis indicated that the metabolic activity of soil microbial community in high yield paddy soils were stronger than the control. Moreover, the difference range from large to small showed as tillering stage > harvest period > seedling period > rotation period, the stronger the rice growth, the greater the difference between the high yield region and the control. At tillering stage and harvest stage, due to the vigorous plant growth, the root exudates were rich, and the microbial communities of high yield paddy soils showed a strong metabolic activity and strong ability to use carbon sources. The results of Shannon, Simpson and McIntosh indices analysis indicated that common microbial species was not a key factor affecting the yield of rice. Tillering stage was a key period for the growth of high yield rice, and many

  20. Genetic diversity affects productivity in early but not late stages of stand development

    Czech Academy of Sciences Publication Activity Database

    Münzbergová, Zuzana; Skálová, Hana; Hadincová, Věroslava

    2009-01-01

    Roč. 10, č. 5 (2009), s. 411-419 ISSN 1439-1791 R&D Projects: GA AV ČR IAA600050820; GA AV ČR(CZ) IAA600050623; GA ČR GA206/06/0098 Institutional research plan: CEZ:AV0Z60050516 Keywords : clonal grass * complementarity * diversity-productivity relationships Subject RIV: EF - Botanics Impact factor: 2.422, year: 2009

  1. Genetic diversity of high performance cultivars of upland and irrigated Brazilian rice.

    Science.gov (United States)

    Coelho, G R C; Brondani, C; Hoffmann, L V; Valdisser, P A M R; Borba, T C O; Mendonça, J A; Rodrigues, L A; de Menezes, I P P

    2017-09-21

    The objective of this study was to analyze the diversity and discrimination of high-performance Brazilian rice cultivars using microsatellite markers. Twenty-nine rice cultivars belonging to EMBRAPA Arroz e Feijão germplasm bank in Brazil were genotyped by 24 SSR markers to establish their structure and genetic discrimination. It was demonstrated that the analyzed germplasm of rice presents an expressive and significant genetic diversity with low heterogeneity among the cultivars. All 29 cultivars were differentiated genetically, and were organized into two groups related to their upland and irrigated cultivation systems. These groups showed a high genetic differentiation, with greater diversity within the group that includes the cultivars for irrigated system. The genotyping data of these cultivars, with the morphological e phenotypical data, are valuable information to be used by rice breeding programs to develop new improved cultivars.

  2. High endemism and stem density distinguish New Caledonian from other high-diversity rainforests in the Southwest Pacific.

    Science.gov (United States)

    Ibanez, Thomas; Blanchard, E; Hequet, V; Keppel, G; Laidlaw, M; Pouteau, R; Vandrot, H; Birnbaum, P

    2018-01-25

    The biodiversity hotspot of New Caledonia is globally renowned for the diversity and endemism of its flora. New Caledonia's tropical rainforests have been reported to have higher stem densities, higher concentrations of relictual lineages and higher endemism than other rainforests. This study investigates whether these aspects differ in New Caledonian rainforests compared to other high-diversity rainforests in the Southwest Pacific. Plants (with a diameter at breast height ≥10 cm) were surveyed in nine 1-ha rainforest plots across the main island of New Caledonia and compared with 14 1-ha plots in high-diversity rainforests of the Southwest Pacific (in Australia, Fiji, Papua New Guinea and the Solomon Islands). This facilitated a comparison of stem densities, taxonomic composition and diversity, and species turnover among plots and countries. The study inventoried 11 280 stems belonging to 335 species (93 species ha-1 on average) in New Caledonia. In comparison with other rainforests in the Southwest Pacific, New Caledonian rainforests exhibited higher stem density (1253 stems ha-1 on average) including abundant palms and tree ferns, with the high abundance of the latter being unparalleled outside New Caledonia. In all plots, the density of relictual species was ≥10 % for both stems and species, with no discernible differences among countries. Species endemism, reaching 89 % on average, was significantly higher in New Caledonia. Overall, species turnover increased with geographical distance, but not among New Caledonian plots. High stem density, high endemism and a high abundance of tree ferns with stem diameters ≥10 cm are therefore unique characteristics of New Caledonian rainforests. High endemism and high spatial species turnover imply that the current system consisting of a few protected areas is inadequate, and that the spatial distribution of plant species needs to be considered to adequately protect the exceptional flora of New Caledonian rainforests

  3. User Generated Diversity - Some reflections on how to improve the quality of amateur productions

    NARCIS (Netherlands)

    Helberger, N.; Leurdijk, A.G.D.; Munck, S.G.E. de

    2010-01-01

    The potential of user created content to make a meaningful contribution to media diversity is subject to debates. Central to these debates is the argument of the quality of amateur productions. This article will take a close look at this argument, and make some suggestions on how to improve the

  4. User generated diversity: some reflections on how to improve the quality of amateur productions

    NARCIS (Netherlands)

    Helberger, N.; Leurdijk, A.; de Munck, S.

    2010-01-01

    The potential of user created content to make a meaningful contribution to media diversity is subject to debates. Central to these debates is the argument of the quality of amateur productions. This article will take a close look at this argument, and make some suggestions on how to improve the

  5. De novo assembly of highly diverse viral populations

    Directory of Open Access Journals (Sweden)

    Yang Xiao

    2012-09-01

    Full Text Available Abstract Background Extensive genetic diversity in viral populations within infected hosts and the divergence of variants from existing reference genomes impede the analysis of deep viral sequencing data. A de novo population consensus assembly is valuable both as a single linear representation of the population and as a backbone on which intra-host variants can be accurately mapped. The availability of consensus assemblies and robustly mapped variants are crucial to the genetic study of viral disease progression, transmission dynamics, and viral evolution. Existing de novo assembly techniques fail to robustly assemble ultra-deep sequence data from genetically heterogeneous populations such as viruses into full-length genomes due to the presence of extensive genetic variability, contaminants, and variable sequence coverage. Results We present VICUNA, a de novo assembly algorithm suitable for generating consensus assemblies from genetically heterogeneous populations. We demonstrate its effectiveness on Dengue, Human Immunodeficiency and West Nile viral populations, representing a range of intra-host diversity. Compared to state-of-the-art assemblers designed for haploid or diploid systems, VICUNA recovers full-length consensus and captures insertion/deletion polymorphisms in diverse samples. Final assemblies maintain a high base calling accuracy. VICUNA program is publicly available at: http://www.broadinstitute.org/scientific-community/science/projects/viral-genomics/ viral-genomics-analysis-software. Conclusions We developed VICUNA, a publicly available software tool, that enables consensus assembly of ultra-deep sequence derived from diverse viral populations. While VICUNA was developed for the analysis of viral populations, its application to other heterogeneous sequence data sets such as metagenomic or tumor cell population samples may prove beneficial in these fields of research.

  6. Culture-Dependent and Independent Studies of Microbial Diversity in Highly Copper-Contaminated Chilean Marine Sediments

    NARCIS (Netherlands)

    Besaury, L.; Marty, F.; Buquet, S.; Mesnage, V.; Muijzer, G.; Quillet, L.

    2013-01-01

    Cultivation and molecular-based approaches were used to study microbial diversity in two Chilean marine sediments contaminated with high (835 ppm) and very high concentrations of copper (1,533 ppm). The diversity of cultivable bacteria resistant to copper was studied at oxic and anoxic conditions,

  7. Fluid diversion in oil recovery

    International Nuclear Information System (INIS)

    Nimir, Hassan B.

    1999-01-01

    In any oil recovery process, large scale heterogeneities, such as fractures, channels, or high-permeability streaks, can cause early break through of injected fluid which will reduce oil recovery efficiency. In waterflooding, enhanced oil recovery, and acidizing operations, this problem is particularly acute because of the cost of the injected fluid. On the other hand coping with excess water production is always a challenging task for field operators. The cost of handling and disposing produced water can significantly shorten the economic production life of an oil well. The hydrostatic pressure created by high fluid levels in a well (water coning) is also detrimental to oil production. In this paper, the concept of fluid diversion is explained. Different methods that are suggested to divert the fluid into the oil-bearing-zones are briefly discussed, to show their advantages and disadvantages. Methods of reducing water production in production well are also discussed. (Author)

  8. Weed Diversity Affects Soybean and Maize Yield in a Long Term Experiment in Michigan, USA.

    Science.gov (United States)

    Ferrero, Rosana; Lima, Mauricio; Davis, Adam S; Gonzalez-Andujar, Jose L

    2017-01-01

    Managing production environments in ways that promote weed community diversity may enhance both crop production and the development of a more sustainable agriculture. This study analyzed data of productivity of maize (corn) and soybean in plots in the Main Cropping System Experiment (MCSE) at the W. K. Kellogg Biological Station Long-Term Ecological Research (KBS-LTER) in Michigan, USA, from 1996 to 2011. We used models derived from population ecology to explore how weed diversity, temperature, and precipitation interact with crop yields. Using three types of models that considered internal and external (climate and weeds) factors, with additive or non-linear variants, we found that changes in weed diversity were associated with changes in rates of crop yield increase over time for both maize and soybeans. The intrinsic capacity for soybean yield increase in response to the environment was greater under more diverse weed communities. Soybean production risks were greatest in the least weed diverse systems, in which each weed species lost was associated with progressively greater crop yield losses. Managing for weed community diversity, while suppressing dominant, highly competitive weeds, may be a helpful strategy for supporting long term increases in soybean productivity. In maize, there was a negative and non-additive response of yields to the interaction between weed diversity and minimum air temperatures. When cold temperatures constrained potential maize productivity through limited resources, negative interactions with weed diversity became more pronounced. We suggest that: (1) maize was less competitive in cold years allowing higher weed diversity and the dominance of some weed species; or (2) that cold years resulted in increased weed richness and prevalence of competitive weeds, thus reducing crop yields. Therefore, we propose to control dominant weed species especially in the years of low yield and extreme minimum temperatures to improve maize yields

  9. Epibenthic diversity and productivity on a heavily trawled Barents Sea bank (Tromsøflaket

    Directory of Open Access Journals (Sweden)

    Monika Kędra

    2017-04-01

    Full Text Available Shallow Arctic banks have been observed to harbour rich communities of epifaunal organisms, but have not been well-studied with respect to composition or function due to sampling challenges. In order to determine how these banks function in the Barents Sea ecosystem, we used a combination of video and trawl/dredge sampling at several locations on a heavily trawled bank, Tromsøflaket – located at the southwestern entrance to the Barents Sea. We describe components of the benthic community, and calculate secondary production of dominant epifaunal organisms. Forty-six epibenthic taxa were identified, and sponges were a significant part of the surveyed benthic communities. There were differences in diversity and production among areas, mainly related to the intensity of trawling activities. Gamma was the most diverse and productive area, with highest species abundance and biomass. Trawled areas had considerably lower species numbers, and significant differences in epifaunal abundance and biomass were found between all trawled and untrawled areas. Trawling seems to have an impact on the sponge communities: mean individual poriferan biomass was higher in untrawled areas, and, although poriferans were observed in areas subjected to more intensive trawling, they were at least five times less frequent than in untrawled areas.

  10. High-throughput genotyping for species identification and diversity assessment in germplasm collections.

    Science.gov (United States)

    Mason, Annaliese S; Zhang, Jing; Tollenaere, Reece; Vasquez Teuber, Paula; Dalton-Morgan, Jessica; Hu, Liyong; Yan, Guijun; Edwards, David; Redden, Robert; Batley, Jacqueline

    2015-09-01

    Germplasm collections provide an extremely valuable resource for breeders and researchers. However, misclassification of accessions by species often hinders the effective use of these collections. We propose that use of high-throughput genotyping tools can provide a fast, efficient and cost-effective way of confirming species in germplasm collections, as well as providing valuable genetic diversity data. We genotyped 180 Brassicaceae samples sourced from the Australian Grains Genebank across the recently released Illumina Infinium Brassica 60K SNP array. Of these, 76 were provided on the basis of suspected misclassification and another 104 were sourced independently from the germplasm collection. Presence of the A- and C-genomes combined with principle components analysis clearly separated Brassica rapa, B. oleracea, B. napus, B. carinata and B. juncea samples into distinct species groups. Several lines were further validated using chromosome counts. Overall, 18% of samples (32/180) were misclassified on the basis of species. Within these 180 samples, 23/76 (30%) supplied on the basis of suspected misclassification were misclassified, and 9/105 (9%) of the samples randomly sourced from the Australian Grains Genebank were misclassified. Surprisingly, several individuals were also found to be the product of interspecific hybridization events. The SNP (single nucleotide polymorphism) array proved effective at confirming species, and provided useful information related to genetic diversity. As similar genomic resources become available for different crops, high-throughput molecular genotyping will offer an efficient and cost-effective method to screen germplasm collections worldwide, facilitating more effective use of these valuable resources by breeders and researchers. © 2015 John Wiley & Sons Ltd.

  11. Diversity and Control of Spoilage Fungi in Dairy Products: An Update

    Science.gov (United States)

    Valence, Florence; Mounier, Jérôme

    2017-01-01

    Fungi are common contaminants of dairy products, which provide a favorable niche for their growth. They are responsible for visible or non-visible defects, such as off-odor and -flavor, and lead to significant food waste and losses as well as important economic losses. Control of fungal spoilage is a major concern for industrials and scientists that are looking for efficient solutions to prevent and/or limit fungal spoilage in dairy products. Several traditional methods also called traditional hurdle technologies are implemented and combined to prevent and control such contaminations. Prevention methods include good manufacturing and hygiene practices, air filtration, and decontamination systems, while control methods include inactivation treatments, temperature control, and modified atmosphere packaging. However, despite technology advances in existing preservation methods, fungal spoilage is still an issue for dairy manufacturers and in recent years, new (bio) preservation technologies are being developed such as the use of bioprotective cultures. This review summarizes our current knowledge on the diversity of spoilage fungi in dairy products and the traditional and (potentially) new hurdle technologies to control their occurrence in dairy foods. PMID:28788096

  12. Diversity and Control of Spoilage Fungi in Dairy Products: An Update

    Directory of Open Access Journals (Sweden)

    Lucille Garnier

    2017-07-01

    Full Text Available Fungi are common contaminants of dairy products, which provide a favorable niche for their growth. They are responsible for visible or non-visible defects, such as off-odor and -flavor, and lead to significant food waste and losses as well as important economic losses. Control of fungal spoilage is a major concern for industrials and scientists that are looking for efficient solutions to prevent and/or limit fungal spoilage in dairy products. Several traditional methods also called traditional hurdle technologies are implemented and combined to prevent and control such contaminations. Prevention methods include good manufacturing and hygiene practices, air filtration, and decontamination systems, while control methods include inactivation treatments, temperature control, and modified atmosphere packaging. However, despite technology advances in existing preservation methods, fungal spoilage is still an issue for dairy manufacturers and in recent years, new (bio preservation technologies are being developed such as the use of bioprotective cultures. This review summarizes our current knowledge on the diversity of spoilage fungi in dairy products and the traditional and (potentially new hurdle technologies to control their occurrence in dairy foods.

  13. Can the reproductive system of a rare and narrowly endemic plant species explain its high genetic diversity?

    Directory of Open Access Journals (Sweden)

    Daniele M. Rodrigues

    2018-01-01

    Full Text Available ABSTRACT The reproductive system of flowering plants can be highly variable, affecting their biology, gene flow and genetic variability among populations. Petunia secreta is a rare annual endemic species of Pedra do Segredo, located in the municipality of Caçapava do Sul, state of Rio Grande do Sul, Brazil. Although rare, the species possesses a high level of genetic variability. We investigated the reproductive system of P. secreta, including fruit production and seed germinability, in order to determine if its reproductive system can explain its genetic diversity. We sampled five populations and conducted five greenhouse hand-pollination treatments: 1 autonomous apomixis; 2 self-pollination; 3 hand self-pollination; 4 geitonogamy; and 5 cross-pollination. We analysed a total of 40 plants, 468 flowers, and 6,500 seeds. Only autonomous apomixis and self-pollination did not produce fruit. No differences in fruit weight were observed among pollination treatments (P > 0.05. Seeds of two colours were produced, with no differences in germinability. Considering all plants, populations, and treatments, the average germinability was 73 % (range 9 % to 100 %. These results, along with other previous studies, indicate that the reproductive systems of P. secreta, and its large effective population size, can explain its high genetic diversity.

  14. Caryophyllene driven diversity in an one-pot rearrangement of oxidation and transanular reactions

    Science.gov (United States)

    Tang, Hao-Yu; Quan, Lu-Lu; Yu, Jie; Zhang, Qiang; Gao, Jin-Ming

    2018-03-01

    Diversity oriented synthesis starting from natural products is a newly coming strategy to build diverse skeletons to meet the demands of high throughput screening in drug development. Caryophyllene was being considered as an ideal starting point to build divers natural-like sesquiterpenes due to its rich sources and build-in reactivity. In this paper, six new natural-like products (2-7) were synthesized form the natural cryophyllene oxide via cascade oxidation and transannular reactions in a one-pot procedure. Their structures were elucidated by exhaustive spectra method including 2D NMR and X-ray diffraction. Of the products, compounds 6 and 7 possess very similar skeleton to natural products. Our findings demonstrated that one-pot cascade reactions on macrocyclic natural products is a concise strategy to create diverse natural-like skeletons.

  15. Investigations of the diverse corrosion products on steel in a hydrogen sulfide environment

    International Nuclear Information System (INIS)

    Bai, Pengpeng; Zheng, Shuqi; Zhao, Hui; Ding, Yu; Wu, Jian; Chen, Changfeng

    2014-01-01

    Highlights: • Diverse corrosion products on steel are investigated in H 2 S environment. • The sequence of the main corrosion products is mackinawite + cubic FeS → troilite. • The large single beam-shaped troilite has a growth pattern along the c axis. • The flower-like troilite develops from beam- or hexagonal wire-shaped grains. • The corresponding crystal structure and morphology of the products are provided. - Abstract: The corrosion products of carbon steel in aqueous H 2 S environment are investigated. The products, which include mackinawite, cubic FeS, troilite, and pyrite, are characterized through their shapes, chemical compositions and crystal structures. Mackinawite appears with a flake shape. Cubic FeS has a perfect/truncated octahedral shape, and pyrite is framboid-shaped. Flower-shaped troilite is developed from beam- or hexagonal wire-shaped grains by electrostatic interactions along a certain lattice plane. The large single beam-shaped troilite has a growth pattern along the c axis. The corresponding crystal structure and micro-morphology of the corrosion products are provided, and the three-dimensional models of them are generated

  16. NCI Program for Natural Product Discovery: A Publicly-Accessible Library of Natural Product Fractions for High-Throughput Screening.

    Science.gov (United States)

    Thornburg, Christopher C; Britt, John R; Evans, Jason R; Akee, Rhone K; Whitt, James A; Trinh, Spencer K; Harris, Matthew J; Thompson, Jerell R; Ewing, Teresa L; Shipley, Suzanne M; Grothaus, Paul G; Newman, David J; Schneider, Joel P; Grkovic, Tanja; O'Keefe, Barry R

    2018-06-13

    The US National Cancer Institute's (NCI) Natural Product Repository is one of the world's largest, most diverse collections of natural products containing over 230,000 unique extracts derived from plant, marine, and microbial organisms that have been collected from biodiverse regions throughout the world. Importantly, this national resource is available to the research community for the screening of extracts and the isolation of bioactive natural products. However, despite the success of natural products in drug discovery, compatibility issues that make extracts challenging for liquid handling systems, extended timelines that complicate natural product-based drug discovery efforts and the presence of pan-assay interfering compounds have reduced enthusiasm for the high-throughput screening (HTS) of crude natural product extract libraries in targeted assay systems. To address these limitations, the NCI Program for Natural Product Discovery (NPNPD), a newly launched, national program to advance natural product discovery technologies and facilitate the discovery of structurally defined, validated lead molecules ready for translation will create a prefractionated library from over 125,000 natural product extracts with the aim of producing a publicly-accessible, HTS-amenable library of >1,000,000 fractions. This library, representing perhaps the largest accumulation of natural-product based fractions in the world, will be made available free of charge in 384-well plates for screening against all disease states in an effort to reinvigorate natural product-based drug discovery.

  17. Chemical diversity of microbial volatiles and their potential for plant growth and productivity

    Directory of Open Access Journals (Sweden)

    CHIDANANDA NAGAMANGALA KANCHISWAMY

    2015-03-01

    Full Text Available Microbial volatile organic compounds (MVOCs are produced by a wide array of microorganisms ranging from bacteria to fungi. A growing body of evidence indicates that MVOCs are ecofriendly and can be exploited as a cost-effective sustainable strategy for use in agricultural practice as agents that enhance plant growth, productivity and disease resistance. As naturally occurring chemicals, MVOCs have potential as possible alternatives to harmful pesticides, fungicides and bactericides as well as genetic modification. Recent studies performed under open field conditions demonstrate that efficiently adopting MVOCs may contribute to sustainable crop protection and production. We review here the chemical diversity of MVOCs and their potential physiological effects on crops and analyze potential and actual limitations for MVOC use as a sustainable strategy for improving productivity and reducing pesticide use.

  18. Scaling up the diversity-resilience relationship with trait databases and remote sensing data: the recovery of productivity after wildfire.

    Science.gov (United States)

    Spasojevic, Marko J; Bahlai, Christie A; Bradley, Bethany A; Butterfield, Bradley J; Tuanmu, Mao-Ning; Sistla, Seeta; Wiederholt, Ruscena; Suding, Katharine N

    2016-04-01

    Understanding the mechanisms underlying ecosystem resilience - why some systems have an irreversible response to disturbances while others recover - is critical for conserving biodiversity and ecosystem function in the face of global change. Despite the widespread acceptance of a positive relationship between biodiversity and resilience, empirical evidence for this relationship remains fairly limited in scope and localized in scale. Assessing resilience at the large landscape and regional scales most relevant to land management and conservation practices has been limited by the ability to measure both diversity and resilience over large spatial scales. Here, we combined tools used in large-scale studies of biodiversity (remote sensing and trait databases) with theoretical advances developed from small-scale experiments to ask whether the functional diversity within a range of woodland and forest ecosystems influences the recovery of productivity after wildfires across the four-corner region of the United States. We additionally asked how environmental variation (topography, macroclimate) across this geographic region influences such resilience, either directly or indirectly via changes in functional diversity. Using path analysis, we found that functional diversity in regeneration traits (fire tolerance, fire resistance, resprout ability) was a stronger predictor of the recovery of productivity after wildfire than the functional diversity of seed mass or species richness. Moreover, slope, elevation, and aspect either directly or indirectly influenced the recovery of productivity, likely via their effect on microclimate, while macroclimate had no direct or indirect effects. Our study provides some of the first direct empirical evidence for functional diversity increasing resilience at large spatial scales. Our approach highlights the power of combining theory based on local-scale studies with tools used in studies at large spatial scales and trait databases to

  19. Association of high-risk sexual behaviour with diversity of the vaginal microbiota and abundance of Lactobacillus.

    Science.gov (United States)

    Wessels, Jocelyn M; Lajoie, Julie; Vitali, Danielle; Omollo, Kenneth; Kimani, Joshua; Oyugi, Julius; Cheruiyot, Juliana; Kimani, Makubo; Mungai, John N; Akolo, Maureen; Stearns, Jennifer C; Surette, Michael G; Fowke, Keith R; Kaushic, Charu

    2017-01-01

    To compare the vaginal microbiota of women engaged in high-risk sexual behaviour (sex work) with women who are not engaged in high-risk sexual behaviour. Diverse vaginal microbiota, low in Lactobacillus species, like those in bacterial vaginosis (BV), are associated with increased prevalence of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) acquisition. Although high-risk sexual behaviour increases risk for STIs, the vaginal microbiota of sex workers is understudied. A retrospective cross-sectional study was conducted comparing vaginal microbiota of women who are not engaged in sex work (non-sex worker controls, NSW, N = 19) and women engaged in sex work (female sex workers, FSW, N = 48), using Illumina sequencing (16S rRNA, V3 region). Bacterial richness and diversity were significantly less in controls, than FSW. Controls were more likely to have Lactobacillus as the most abundant genus (58% vs. 17%; P = 0.002) and composition of their vaginal microbiota differed from FSW (PERMANOVA, P = 0.001). Six microbiota clusters were detected, including a high diversity cluster with three sub-clusters, and 55% of women with low Nugent Scores fell within this cluster. High diversity was observed by 16S sequencing in FSW, regardless of Nugent Scores, suggesting that Nugent Score may not be capable of capturing the diversity present in the FSW vaginal microbiota. High-risk sexual behaviour is associated with diversity of the vaginal microbiota and lack of Lactobacillus. These factors could contribute to increased risk of STIs and HIV in women engaged in high-risk sexual behaviour.

  20. Association of high-risk sexual behaviour with diversity of the vaginal microbiota and abundance of Lactobacillus.

    Directory of Open Access Journals (Sweden)

    Jocelyn M Wessels

    Full Text Available To compare the vaginal microbiota of women engaged in high-risk sexual behaviour (sex work with women who are not engaged in high-risk sexual behaviour. Diverse vaginal microbiota, low in Lactobacillus species, like those in bacterial vaginosis (BV, are associated with increased prevalence of sexually transmitted infections (STIs and human immunodeficiency virus (HIV acquisition. Although high-risk sexual behaviour increases risk for STIs, the vaginal microbiota of sex workers is understudied.A retrospective cross-sectional study was conducted comparing vaginal microbiota of women who are not engaged in sex work (non-sex worker controls, NSW, N = 19 and women engaged in sex work (female sex workers, FSW, N = 48, using Illumina sequencing (16S rRNA, V3 region.Bacterial richness and diversity were significantly less in controls, than FSW. Controls were more likely to have Lactobacillus as the most abundant genus (58% vs. 17%; P = 0.002 and composition of their vaginal microbiota differed from FSW (PERMANOVA, P = 0.001. Six microbiota clusters were detected, including a high diversity cluster with three sub-clusters, and 55% of women with low Nugent Scores fell within this cluster. High diversity was observed by 16S sequencing in FSW, regardless of Nugent Scores, suggesting that Nugent Score may not be capable of capturing the diversity present in the FSW vaginal microbiota.High-risk sexual behaviour is associated with diversity of the vaginal microbiota and lack of Lactobacillus. These factors could contribute to increased risk of STIs and HIV in women engaged in high-risk sexual behaviour.

  1. Association of high-risk sexual behaviour with diversity of the vaginal microbiota and abundance of Lactobacillus

    Science.gov (United States)

    Wessels, Jocelyn M.; Lajoie, Julie; Vitali, Danielle; Omollo, Kenneth; Kimani, Joshua; Oyugi, Julius; Cheruiyot, Juliana; Kimani, Makubo; Mungai, John N.; Akolo, Maureen; Stearns, Jennifer C.; Surette, Michael G.; Fowke, Keith R.

    2017-01-01

    Objective To compare the vaginal microbiota of women engaged in high-risk sexual behaviour (sex work) with women who are not engaged in high-risk sexual behaviour. Diverse vaginal microbiota, low in Lactobacillus species, like those in bacterial vaginosis (BV), are associated with increased prevalence of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) acquisition. Although high-risk sexual behaviour increases risk for STIs, the vaginal microbiota of sex workers is understudied. Methods A retrospective cross-sectional study was conducted comparing vaginal microbiota of women who are not engaged in sex work (non-sex worker controls, NSW, N = 19) and women engaged in sex work (female sex workers, FSW, N = 48), using Illumina sequencing (16S rRNA, V3 region). Results Bacterial richness and diversity were significantly less in controls, than FSW. Controls were more likely to have Lactobacillus as the most abundant genus (58% vs. 17%; P = 0.002) and composition of their vaginal microbiota differed from FSW (PERMANOVA, P = 0.001). Six microbiota clusters were detected, including a high diversity cluster with three sub-clusters, and 55% of women with low Nugent Scores fell within this cluster. High diversity was observed by 16S sequencing in FSW, regardless of Nugent Scores, suggesting that Nugent Score may not be capable of capturing the diversity present in the FSW vaginal microbiota. Conclusions High-risk sexual behaviour is associated with diversity of the vaginal microbiota and lack of Lactobacillus. These factors could contribute to increased risk of STIs and HIV in women engaged in high-risk sexual behaviour. PMID:29095928

  2. Determination of a Screening Metric for High Diversity DNA Libraries.

    Science.gov (United States)

    Guido, Nicholas J; Handerson, Steven; Joseph, Elaine M; Leake, Devin; Kung, Li A

    2016-01-01

    The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

  3. Determination of a Screening Metric for High Diversity DNA Libraries.

    Directory of Open Access Journals (Sweden)

    Nicholas J Guido

    Full Text Available The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

  4. Molecular analyses reveal high species diversity of trematodes in a sub-Arctic lake

    Science.gov (United States)

    Soldánová, Miroslava; Georgieva, Simona; Roháčováa, Jana; Knudsen, Rune; Kuhn, Jesper A.; Henriksen, Eirik H.; Siwertsson, Anna; Shaw, Jenny C.; Kuris, Armand M.; Amundsen, Per-Arne; Scholz, Tomáš; Lafferty, Kevin D.; Kostadinova, Aneta

    2017-01-01

    To identify trematode diversity and life-cycles in the sub-Arctic Lake Takvatn, Norway, we characterised 120 trematode isolates from mollusc first intermediate hosts, metacercariae from second intermediate host fishes and invertebrates, and adults from fish and invertebrate definitive hosts, using molecular techniques. Phylogenies based on nuclear and/or mtDNA revealed high species richness (24 species or species-level genetic lineages), and uncovered trematode diversity (16 putative new species) from five families typical in lake ecosystems (Allocreadiidae, Diplostomidae, Plagiorchiidae, Schistosomatidae and Strigeidae). Sampling potential invertebrate hosts allowed matching of sequence data for different stages, thus achieving molecular elucidation of trematode life-cycles and exploration of host-parasite interactions. Phylogenetic analyses also helped identify three major mollusc intermediate hosts (Radix balthica, Pisidium casertanum and Sphaerium sp.) in the lake. Our findings increase the known trematode diversity at the sub-Arctic Lake Takvatn, showing that digenean diversity is high in this otherwise depauperate sub-Arctic freshwater ecosystem, and indicating that sub-Arctic and Arctic ecosystems may be characterised by unique trematode assemblages.

  5. Genetic diversity for fermentable carbohydrates production in alfalfa

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, Y.; Bertrand, A.; Duceppe, M.O.; Dube, M.P.; Michaud, R. [Agriculture and Agri-Food Canada, Quebec City, PQ (Canada)

    2009-07-01

    Alfalfa has many attributes that renders it suitable for bioethanol production, including its adaptability to diverse environmental conditions without any need for nitrogen fertilizer. However research is needed to develop biofuel-type alfalfa with improved biomass production and standability, increased persistence, and better cell wall degradability. The ethanol conversion rates from alfalfa biomass could be increased by genetically improving the accumulation of readily fermentable non-structural carbohydrates (NSC). This presentation reported on a screening project where genotypes with superior cell wall degradability were identified. NSC accumulation within 300 genotypes was randomly selected within six genetic backgrounds from Europe and North America. Biochemical analyses of dried stems revealed a large genetic variability for NSC content, with concentrations ranging from 20 to 100 mg per g DW. NSC variability was considerably higher in a genetic background of European origin compared to the other populations, therefore emphasizing the potential for genetic improvement for that trait. A modified commercial enzymatic cocktail known as AcceleraseTM 1000 Genencor is being developed to optimize the degradation of alfalfa biomass. DNA extracted from genotypes with the highest and lowest cell wall degradability or NSC accumulation will be pooled and used for bulk segregant analysis of DNA polymorphisms using the PCR-based sequence-related amplified polymorphism technique. It was concluded that the commercial release of biofuel-type alfalfa can be accelerated if the genetic markers associated with these traits can be identified.

  6. Construction of 1,3,4-Oxadiazole and 1,3,4-Thiadiazole Library with a High Level of Skeletal Diversity Based on Branching Diversity-Oriented Synthesis on Solid-Phase Supports.

    Science.gov (United States)

    Ha, Ji-Eun; Yang, Seung-Ju; Gong, Young-Dae

    2018-02-12

    An efficient solid-phase synthetic route for the construction of 1,3,4-oxadiazole and 1,3,4-thiadiazole libraries based on branching diversity-oriented synthesis (DOS) has been developed in this study. The core skeleton resins, 1,3,4-oxadiazole and 1,3,4-thiadiazole, were obtained through desulfurative and dehydrative cyclizations of thiosemicarbazide resin, respectively. Various functional groups have been introduced to the core skeleton resins, such as aryl, amine, amide, urea, thiourea, and an amino acid. Most of the libraries were purified by simple trituration without extraction or column chromatography after cleavage of the products from the solid-supported resin. As a result, we obtained high yields of pure 1,3,4-oxadiazole and 1,3,4-thiadiazole derivatives (total numbers = 128). Finally, we confirmed the drug-like properties of our library by calculation of physicochemical properties, displays of the skeletal diversities of the library in 3D-space, and occupation of a broad range of areas by their functional groups.

  7. A secretory system for bacterial production of high-profile protein targets

    DEFF Research Database (Denmark)

    Kotzsch, Alexander; Vernet, Erik; Hammarström, Martin

    2011-01-01

    Escherichia coli represents a robust, inexpensive expression host for the production of recombinant proteins. However, one major limitation is that certain protein classes do not express well in a biologically relevant form using standard expression approaches in the cytoplasm of E. coli. To impr......Escherichia coli represents a robust, inexpensive expression host for the production of recombinant proteins. However, one major limitation is that certain protein classes do not express well in a biologically relevant form using standard expression approaches in the cytoplasm of E. coli...... membrane protein F (OmpF) and osmotically inducible protein Y (OsmY). Based on the results of this initial study, we carried out an extended expression screen employing the OsmY fusion and multiple constructs of a more diverse set of human proteins. Using this high-throughput compatible system, we clearly...

  8. The pig gut microbial diversity: Understanding the pig gut microbial ecology through the next generation high throughput sequencing.

    Science.gov (United States)

    Kim, Hyeun Bum; Isaacson, Richard E

    2015-06-12

    The importance of the gut microbiota of animals is widely acknowledged because of its pivotal roles in the health and well being of animals. The genetic diversity of the gut microbiota contributes to the overall development and metabolic needs of the animal, and provides the host with many beneficial functions including production of volatile fatty acids, re-cycling of bile salts, production of vitamin K, cellulose digestion, and development of immune system. Thus the intestinal microbiota of animals has been the subject of study for many decades. Although most of the older studies have used culture dependent methods, the recent advent of high throughput sequencing of 16S rRNA genes has facilitated in depth studies exploring microbial populations and their dynamics in the animal gut. These culture independent DNA based studies generate large amounts of data and as a result contribute to a more detailed understanding of the microbiota dynamics in the gut and the ecology of the microbial populations. Of equal importance, is being able to identify and quantify microbes that are difficult to grow or that have not been grown in the laboratory. Interpreting the data obtained from this type of study requires using basic principles of microbial diversity to understand importance of the composition of microbial populations. In this review, we summarize the literature on culture independent studies of the pig gut microbiota with an emphasis on its succession and alterations caused by diverse factors. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Diversity of lactic acid bacteria associated with traditional fermented dairy products in Mongolia.

    Science.gov (United States)

    Yu, J; Wang, W H; Menghe, B L G; Jiri, M T; Wang, H M; Liu, W J; Bao, Q H; Lu, Q; Zhang, J C; Wang, F; Xu, H Y; Sun, T S; Zhang, H P

    2011-07-01

    Spontaneous milk fermentation has a long history in Mongolia, and beneficial microorganisms have been handed down from one generation to the next for use in fermented dairy products. The objective of this study was to investigate the diversity of lactic acid bacteria (LAB) communities in fermented yak, mare, goat, and cow milk products by analyzing 189 samples collected from 13 different regions in Mongolia. The LAB counts in these samples varied from 3.41 to 9.03 log cfu/mL. Fermented yak and mare milks had almost identical mean numbers of LAB, which were significantly higher than those in fermented goat milk but slightly lower than those in fermented cow milk. In total, 668 isolates were obtained from these samples using de Man, Rogosa, and Sharpe agar and M17 agar. Each isolate was considered to be presumptive LAB based on gram-positive and catalase-negative properties, and was identified at the species level by 16S rRNA gene sequencing, multiplex PCR assay, and restriction fragment length polymorphism analysis. All isolates from Mongolian dairy products were accurately identified as Enterococcus faecalis (1 strain), Enterococcus durans (3 strains), Lactobacillus brevis (3 strains), Lactobacillus buchneri (2 strains), Lactobacillus casei (16 strains), Lactobacillus delbrueckii ssp. bulgaricus (142 strains), Lactobacillus diolivorans (17 strains), Lactobacillus fermentum (42 strains), Lactobacillus helveticus (183 strains), Lactobacillus kefiri (6 strains), Lactobacillus plantarum ssp. plantarum (7 strains), Lactococcus lactis ssp. lactis (7 strains), Leuconostoc lactis (22 strains), Leuconostoc mesenteroides (21 strains), Streptococcus thermophilus (195 strains), and Weissella cibaria (1 strain). The predominant LAB were Strep. thermophilus and Lb. helveticus, which were isolated from all sampling sites. The results demonstrate that traditional fermented dairy products from different regions of Mongolia have complex compositions of LAB species. Such diversity of

  10. High shrew diversity on Alaska's Seward Peninsula: Community assembly and environmental change

    Science.gov (United States)

    Hope, Andrew G.

    2012-01-01

    In September 2010, 6 species of shrews (genus: Sorex) were collected at a single locality on the Seward Peninsula of Alaska. Such high sympatric diversity within a single mammalian genus is seldom realized. This phenomenon at high latitudes highlights complex Arctic community dynamics that reflect significant turnover through time as a consequence of environmental change. Each of these shrew species occupies a broad geographic distribution collectively spanning the entire Holarctic, although the study site lies within Eastern Beringia, near the periphery of all individual ranges. A review of published genetic evidence reflects a depauperate shrew community within ice-free Beringia through the last glaciation, and recent assembly of current diversity during the Holocene.

  11. Patterns and drivers of bacterial α- and β-diversity across vertical profiles from surface to subsurface sediments.

    Science.gov (United States)

    Luna, Gian Marco; Corinaldesi, Cinzia; Rastelli, Eugenio; Danovaro, Roberto

    2013-10-01

    We investigated the patterns and drivers of bacterial α- and β-diversity, along with viral and prokaryotic abundance and the carbon production rates, in marine surface and subsurface sediments (down to 1 m depth) in two habitats: vegetated sediments (seagrass meadow) and non-vegetated sediments. Prokaryotic abundance and production decreased with depth in the sediment, but cell-specific production rates and the virus-to-prokaryote ratio increased, highlighting unexpectedly high activity in the subsurface. The highest diversity was observed in vegetated sediments. Bacterial β-diversity between sediment horizons was high, and only a minor number of taxa was shared between surface and subsurface layers. Viruses significantly contributed to explain α- and β-diversity patterns. Despite potential limitations due to the only use of fingerprinting techniques, this study indicates that the coastal subsurface host highly active and diversified bacterial assemblages, that subsurface cells are more active than expected and that viruses promote β-diversity and stimulate bacterial metabolism in subsurface layers. The limited number of taxa shared between habitats, and between surface and subsurface sediment horizons, suggests that future investigations of the shallow subsurface will provide insights into the census of bacterial diversity, and the comprehension of the patterns and drivers of prokaryotic diversity in marine ecosystems. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  12. EMMA: An Extensible Mammalian Modular Assembly Toolkit for the Rapid Design and Production of Diverse Expression Vectors.

    Science.gov (United States)

    Martella, Andrea; Matjusaitis, Mantas; Auxillos, Jamie; Pollard, Steven M; Cai, Yizhi

    2017-07-21

    Mammalian plasmid expression vectors are critical reagents underpinning many facets of research across biology, biomedical research, and the biotechnology industry. Traditional cloning methods often require laborious manual design and assembly of plasmids using tailored sequential cloning steps. This process can be protracted, complicated, expensive, and error-prone. New tools and strategies that facilitate the efficient design and production of bespoke vectors would help relieve a current bottleneck for researchers. To address this, we have developed an extensible mammalian modular assembly kit (EMMA). This enables rapid and efficient modular assembly of mammalian expression vectors in a one-tube, one-step golden-gate cloning reaction, using a standardized library of compatible genetic parts. The high modularity, flexibility, and extensibility of EMMA provide a simple method for the production of functionally diverse mammalian expression vectors. We demonstrate the value of this toolkit by constructing and validating a range of representative vectors, such as transient and stable expression vectors (transposon based vectors), targeting vectors, inducible systems, polycistronic expression cassettes, fusion proteins, and fluorescent reporters. The method also supports simple assembly combinatorial libraries and hierarchical assembly for production of larger multigenetic cargos. In summary, EMMA is compatible with automated production, and novel genetic parts can be easily incorporated, providing new opportunities for mammalian synthetic biology.

  13. Does Gender Diversity in Management Contribute to Profitability, Productivity, and the AA system in China and Korea? (Japanese)

    OpenAIRE

    ISHIZUKA Hiromi

    2014-01-01

    The purpose of this paper is to identify the statistical relationship between the utilization of women and profitability as well as productivity. The paper targets Chinese and Korean companies, which have commonalities in the utilization of women, and aims to use the information gained to recommend policies for the economic development of Japan. The effects of gender diversity in management (GDM), work-life balance (WLB), diversity in management (DM), and others were adopted explicitly during...

  14. Pyrosequencing analysis of the microbial diversity of airag, khoormog and tarag, traditional fermented dairy products of mongolia.

    Science.gov (United States)

    Oki, Kaihei; Dugersuren, Jamyan; Demberel, Shirchin; Watanabe, Koichi

    2014-01-01

    Here, we used pyrosequencing to obtain a detailed analysis of the microbial diversities of traditional fermented dairy products of Mongolia. From 22 Airag (fermented mare's milk), 5 Khoormog (fermented camel's milk) and 26 Tarag (fermented milk of cows, goats and yaks) samples collected in the Mongolian provinces of Arhangai, Bulgan, Dundgobi, Tov, Uburhangai and Umnugobi, we obtained a total of 81 operational taxonomic units, which were assigned to 15 families, 21 genera and 41 species in 3 phyla. The genus Lactobacillus is a core bacterial component of Mongolian fermented milks, and Lactobacillus helveticus, Lactobacillus kefiranofaciens and Lactobacillus delbrueckii were the predominant species of lactic acid bacteria (LAB) in the Airag, Khoormog and Tarag samples, respectively. By using this pyrosequencing approach, we successfully detected most LAB species that have been isolated as well as seven LAB species that have not been found in our previous culture-based study. A subsequent analysis of the principal components of the samples revealed that L. delbrueckii, L. helveticus, L. kefiranofaciens and Streptococcus thermophilus were the main factors influencing the microbial diversity of these Mongolian traditional fermented dairy products and that this diversity correlated with the animal species from which the milk was sourced.

  15. Diversity and Biosynthetic Potential of Culturable Microbes Associated with Toxic Marine Animals

    Science.gov (United States)

    Chau, Rocky; Kalaitzis, John A.; Wood, Susanna A.; Neilan, Brett A.

    2013-01-01

    Tetrodotoxin (TTX) is a neurotoxin that has been reported from taxonomically diverse organisms across 14 different phyla. The biogenic origin of tetrodotoxin is still disputed, however, TTX biosynthesis by host-associated bacteria has been reported. An investigation into the culturable microbial populations from the TTX-associated blue-ringed octopus Hapalochlaena sp. and sea slug Pleurobranchaea maculata revealed a surprisingly high microbial diversity. Although TTX was not detected among the cultured isolates, PCR screening identifiedsome natural product biosynthesis genes putatively involved in its assembly. This study is the first to report on the microbial diversity of culturable communities from H. maculosa and P. maculata and common natural product biosynthesis genes from their microbiota. We also reassess the production of TTX reported from three bacterial strains isolated from the TTX-containing gastropod Nassarius semiplicatus. PMID:23917066

  16. Diversity and Biosynthetic Potential of Culturable Microbes Associated with Toxic Marine Animals

    Directory of Open Access Journals (Sweden)

    Brett A. Neilan

    2013-08-01

    Full Text Available Tetrodotoxin (TTX is a neurotoxin that has been reported from taxonomically diverse organisms across 14 different phyla. The biogenic origin of tetrodotoxin is still disputed, however, TTX biosynthesis by host-associated bacteria has been reported. An investigation into the culturable microbial populations from the TTX-associated blue-ringed octopus Hapalochlaena sp. and sea slug Pleurobranchaea maculata revealed a surprisingly high microbial diversity. Although TTX was not detected among the cultured isolates, PCR screening identifiedsome natural product biosynthesis genes putatively involved in its assembly. This study is the first to report on the microbial diversity of culturable communities from H. maculosa and P. maculata and common natural product biosynthesis genes from their microbiota. We also reassess the production of TTX reported from three bacterial strains isolated from the TTX-containing gastropod Nassarius semiplicatus.

  17. Diversity loss with persistent human disturbance increases vulnerability to ecosystem collapse.

    Science.gov (United States)

    MacDougall, A S; McCann, K S; Gellner, G; Turkington, R

    2013-02-07

    Long-term and persistent human disturbances have simultaneously altered the stability and diversity of ecological systems, with disturbances directly reducing functional attributes such as invasion resistance, while eliminating the buffering effects of high species diversity. Theory predicts that this combination of environmental change and diversity loss increases the risk of abrupt and potentially irreversible ecosystem collapse, but long-term empirical evidence from natural systems is lacking. Here we demonstrate this relationship in a degraded but species-rich pyrogenic grassland in which the combined effects of fire suppression, invasion and trophic collapse have created a species-poor grassland that is highly productive, resilient to yearly climatic fluctuations, and resistant to invasion, but vulnerable to rapid collapse after the re-introduction of fire. We initially show how human disturbance has created a negative relationship between diversity and function, contrary to theoretical predictions. Fire prevention since the mid-nineteenth century is associated with the loss of plant species but it has stabilized high-yield annual production and invasion resistance, comparable to a managed high-yield low-diversity agricultural system. In managing for fire suppression, however, a hidden vulnerability to sudden environmental change emerges that is explained by the elimination of the buffering effects of high species diversity. With the re-introduction of fire, grasslands only persist in areas with remnant concentrations of native species, in which a range of rare and mostly functionally redundant plants proliferate after burning and prevent extensive invasion including a rapid conversion towards woodland. This research shows how biodiversity can be crucial for ecosystem stability despite appearing functionally insignificant beforehand, a relationship probably applicable to many ecosystems given the globally prevalent combination of intensive long-term land

  18. Co-occurrence of linguistic and biological diversity in biodiversity hotspots and high biodiversity wilderness areas.

    Science.gov (United States)

    Gorenflo, L J; Romaine, Suzanne; Mittermeier, Russell A; Walker-Painemilla, Kristen

    2012-05-22

    As the world grows less biologically diverse, it is becoming less linguistically and culturally diverse as well. Biologists estimate annual loss of species at 1,000 times or more greater than historic rates, and linguists predict that 50-90% of the world's languages will disappear by the end of this century. Prior studies indicate similarities in the geographic arrangement of biological and linguistic diversity, although conclusions have often been constrained by use of data with limited spatial precision. Here we use greatly improved datasets to explore the co-occurrence of linguistic and biological diversity in regions containing many of the Earth's remaining species: biodiversity hotspots and high biodiversity wilderness areas. Results indicate that these regions often contain considerable linguistic diversity, accounting for 70% of all languages on Earth. Moreover, the languages involved are frequently unique (endemic) to particular regions, with many facing extinction. Likely reasons for co-occurrence of linguistic and biological diversity are complex and appear to vary among localities, although strong geographic concordance between biological and linguistic diversity in many areas argues for some form of functional connection. Languages in high biodiversity regions also often co-occur with one or more specific conservation priorities, here defined as endangered species and protected areas, marking particular localities important for maintaining both forms of diversity. The results reported in this article provide a starting point for focused research exploring the relationship between biological and linguistic-cultural diversity, and for developing integrated strategies designed to conserve species and languages in regions rich in both.

  19. Phytoplankton production systems in a shellfish hatchery: variations of the bacterial load and diversity of vibrios.

    Science.gov (United States)

    Dubert, J; Fernández-Pardo, A; Nóvoa, S; Barja, J L; Prado, S

    2015-06-01

    Outbreaks of disease caused by some Vibrio species represent the main production bottleneck in shellfish hatcheries. Although the phytoplankton used as food is one of the main sources of bacteria, studies of the associated bacterial populations, specifically vibrios, are scarce. The aim of the study was the microbiological monitoring of the microalgae as the first step in assessing the risk disease for bivalve cultures. Two phytoplankton production systems were sampled weekly throughout 1-year period in a bivalve hatchery. Quantitative analysis revealed high levels of marine heterotrophic bacteria in both systems throughout the study. Presumptive vibrios were detected occasionally and at low concentrations. In most of the cases, they belonged to the Splendidus and Harveyi clades. The early detection of vibrios in the microalgae may be the key for a successful bivalve culture. Their abundance and diversity were affected by factors related to the hatchery environment. This work represents the first long study where the presence of vibrios was evaluated rigorously in phytoplankton production systems and provides a suitable microbiological protocol to control and guarantee the quality of the algal cultures to avoid the risk of transferring potential pathogens to shellfish larvae and/or broodstock. © 2015 The Society for Applied Microbiology.

  20. Diversity - Essential quality for agronomy

    Science.gov (United States)

    Diversity is an essential quality for success in agronomy because agronomy touches everyone, everywhere in some way, and food production is crucial for every society around the world. Consider, for example, our membership, which is diverse in almost every way imaginable. This diversity brings differ...

  1. High Levels of Genetic Diversity of Plasmodium falciparum Populations in Papua New Guinea despite Variable Infection Prevalence

    Science.gov (United States)

    Barry, Alyssa E.; Schultz, Lee; Senn, Nicholas; Nale, Joe; Kiniboro, Benson; Siba, Peter M.; Mueller, Ivo; Reeder, John C.

    2013-01-01

    High levels of genetic diversity in Plasmodium falciparum populations are an obstacle to malaria control. Here, we investigate the relationship between local variation in malaria epidemiology and parasite genetic diversity in Papua New Guinea (PNG). Cross-sectional malaria surveys were performed in 14 villages spanning four distinct malaria-endemic areas on the north coast, including one area that was sampled during the dry season. High-resolution msp2 genotyping of 2,147 blood samples identified 761 P. falciparum infections containing a total of 1,392 clones whose genotypes were used to measure genetic diversity. Considerable variability in infection prevalence and mean multiplicity of infection was observed at all of the study sites, with the area sampled during the dry season showing particularly striking local variability. Genetic diversity was strongly associated with multiplicity of infection but not with infection prevalence. In highly endemic areas, differences in infection prevalence may not translate into a decrease in parasite population diversity. PMID:23400571

  2. Tree Diversity Enhances Stand Carbon Storage but Not Leaf Area in a Subtropical Forest.

    Science.gov (United States)

    Castro-Izaguirre, Nadia; Chi, Xiulian; Baruffol, Martin; Tang, Zhiyao; Ma, Keping; Schmid, Bernhard; Niklaus, Pascal A

    2016-01-01

    Research about biodiversity-productivity relationships has focused on herbaceous ecosystems, with results from tree field studies only recently beginning to emerge. Also, the latter are concentrated largely in the temperate zone. Tree species diversity generally is much higher in subtropical and tropical than in temperate or boreal forests, with reasons not fully understood. Niche overlap and thus complementarity in the use of resources that support productivity may be lower in forests than in herbaceous ecosystems, suggesting weaker productivity responses to diversity change in forests. We studied stand basal area, vertical structure, leaf area, and their relationship with tree species richness in a subtropical forest in south-east China. Permanent forest plots of 30 x 30 m were selected to span largely independent gradients in tree species richness and secondary successional age. Plots with higher tree species richness had a higher stand basal area. Also, stand basal area increases over a 4-year census interval were larger at high than at low diversity. These effects translated into increased carbon stocks in aboveground phytomass (estimated using allometric equations). A higher variability in tree height in more diverse plots suggested that these effects were facilitated by denser canopy packing due to architectural complementarity between species. In contrast, leaf area was not or even negatively affected by tree diversity, indicating a decoupling of carbon accumulation from leaf area. Alternatively, the same community leaf area might have assimilated more C per time interval in more than in less diverse plots because of differences in leaf turnover and productivity or because of differences in the display of leaves in vertical and horizontal space. Overall, our study suggests that in species-rich forests niche-based processes support a positive diversity-productivity relationship and that this translates into increased carbon storage in long-lived woody

  3. [Agrobacterium rubi strains from blueberry plants are highly diverse].

    Science.gov (United States)

    Abrahamovich, Eliana; López, Ana C; Alippi, Adriana M

    2014-01-01

    The diversity of a collection of Agrobacterium rubi strains isolated from blueberries from different regions of Argentina was studied by conventional microbiological tests and molecular techniques. Results from biochemical and physiological reactions, as well as from rep-PCR and RFLP analysis of PCR-amplified 23S rDNA showed high phenotypic and genotypic intraspecific variation. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

  4. Diversity beyond the Golden Rule.

    Science.gov (United States)

    Carnevale, Anthony P.; Stone, Susan C.

    1994-01-01

    Diversity implies differences in people based on their identifications with various groups and is also a process of acknowledging differences through action. Those organizations that have welcomed diversity are more productive and have a competitive advantage. Diversity training can be awareness based (cognitive) or skill based (behavioral). (JOW)

  5. Spatial pattern affects diversity-productivity relationships in experimental meadow communities

    Science.gov (United States)

    Lamošová, Tereza; Doležal, Jiří; Lanta, Vojtěch; Lepš, Jan

    2010-05-01

    Plant species create aggregations of conspecifics as a consequence of limited seed dispersal, clonal growth and heterogeneous environment. Such intraspecific aggregation increases the importance of intraspecific competition relative to interspecific competition which may slow down competitive exclusion and promote species coexistence. To examine how spatial aggregation impacts the functioning of experimental assemblages of varying species richness, eight perennial grassland species of different growth form were grown in random and aggregated patterns in monocultures, two-, four-, and eight-species mixtures. In mixtures with an aggregated pattern, monospecific clumps were interspecifically segregated. Mixed model ANOVA was used to test (i) how the total productivity and productivity of individual species is affected by the number of species in a mixture, and (ii) how these relationships are affected by spatial pattern of sown plants. The main patterns of productivity response to species richness conform to other studies: non-transgressive overyielding is omnipresent (the productivity of mixtures is higher than the average of its constituent species so that the net diversity, selection and complementarity effects are positive), whereas transgressive overyielding is found only in a minority of cases (average of log(overyielding) being close to zero or negative). The theoretical prediction that plants in a random pattern should produce more than in an aggregated pattern (the distances to neighbours are smaller and consequently the competition among neighbours stronger) was confirmed in monocultures of all the eight species. The situation is more complicated in mixtures, probably as a consequence of complicated interplay between interspecific and intraspecific competition. The most productive species ( Achillea, Holcus, Plantago) were competitively superior and increased their relative productivity with mixture richness. The intraspecific competition of these species is

  6. Desired Diversity and Symptomatic Anxiety

    DEFF Research Database (Denmark)

    Friis Christensen, Jannick; Muhr, Sara Louise

    2018-01-01

    of diversity that, however, constantly change due to the empty form of diversity. Anxiety manifests itself in the obsession of unobtainable idealised forms of diversity as well as in the uncertainty associated with the traumatic experience of always falling short of what is desired in an object...... – the experience of failed diversity. Conclusively, we discuss the productive potential of the power of lack. The impossibility of diversity is what, at once, conditions the possibility of diversity. We therefore suggest that the symptomatic anxiety provoked by the lack should be enjoyed in order to engage...

  7. The interplay of diversity training and diversity beliefs on team creativity in nationality diverse teams.

    Science.gov (United States)

    Homan, Astrid C; Buengeler, Claudia; Eckhoff, Robert A; van Ginkel, Wendy P; Voelpel, Sven C

    2015-09-01

    Attaining value from nationality diversity requires active diversity management, which organizations often employ in the form of diversity training programs. Interestingly, however, the previously reported effects of diversity training are often weak and, sometimes, even negative. This situation calls for research on the conditions under which diversity training helps or harms teams. We propose that diversity training can increase team creativity, but only for teams with less positive pretraining diversity beliefs (i.e., teams with a greater need for such training) and that are sufficiently diverse in nationality. Comparing the creativity of teams that attended nationality diversity training versus control training, we found that for teams with less positive diversity beliefs, diversity training increased creative performance when the team's nationality diversity was high, but undermined creativity when the team's nationality diversity was low. Diversity training had less impact on teams with more positive diversity beliefs, and training effects were not contingent upon these teams' diversity. Speaking to the underlying process, we showed that these interactive effects were driven by the experienced team efficacy of the team members. We discuss theoretical and practical implications for nationality diversity management. (c) 2015 APA, all rights reserved).

  8. High recombination frequency creates genotypic diversity in colonies of the leaf-cutting ant Acromyrmex echinatior

    DEFF Research Database (Denmark)

    Sirviö, A.; Gadau, J.; Rueppell, O.

    2006-01-01

    Honeybees are known to have genetically diverse colonies because queens mate with many males and the recombination rate is extremely high. Genetic diversity among social insect workers has been hypothesized to improve general performance of large and complex colonies, but this idea has not been t...

  9. High genetic diversity in a potentially vulnerable tropical tree species despite extreme habitat loss.

    Directory of Open Access Journals (Sweden)

    Annika M E Noreen

    Full Text Available Over the last 150 years, Singapore's primary forest has been reduced to less than 0.2% of its previous area, resulting in extinctions of native flora and fauna. Remaining species may be threatened by genetic erosion and inbreeding. We surveyed >95% of the remaining primary forest in Singapore and used eight highly polymorphic microsatellite loci to assess genetic diversity indices of 179 adults (>30 cm stem diameter, 193 saplings (>1 yr, and 1,822 seedlings (<1 yr of the canopy tree Koompassia malaccensis (Fabaceae. We tested hypotheses relevant to the genetic consequences of habitat loss: (1 that the K. malaccensis population in Singapore experienced a genetic bottleneck and a reduction in effective population size, and (2 K. malaccensis recruits would exhibit genetic erosion and inbreeding compared to adults. Contrary to expectations, we detected neither a population bottleneck nor a reduction in effective population size, and high genetic diversity in all age classes. Genetic diversity indices among age classes were not significantly different: we detected overall high expected heterozygosity (He = 0.843-0.854, high allelic richness (R = 16.7-19.5, low inbreeding co-efficients (FIS = 0.013-0.076, and a large proportion (30.1% of rare alleles (i.e. frequency <1%. However, spatial genetic structure (SGS analyses showed significant differences between the adults and the recruits. We detected significantly greater SGS intensity, as well as higher relatedness in the 0-10 m distance class, for seedlings and saplings compared to the adults. Demographic factors for this population (i.e. <200 adult trees are a cause for concern, as rare alleles could be lost due to stochastic factors. The high outcrossing rate (tm = 0.961, calculated from seedlings, may be instrumental in maintaining genetic diversity and suggests that pollination by highly mobile bee species in the genus Apis may provide resilience to acute habitat loss.

  10. Awareness of Consequence of High School Students on Loss of Bio-Diversity

    Science.gov (United States)

    Kasot, Nazim; Özbas, Serap

    2015-01-01

    The aim of this study is to assess the egoistic, altruistic and biospheric awareness of the consequence of high school students regarding the loss of bio-diversity, then comparing the results on the basis of some independent variables (gender, class and family income). The research data were collected from 884 ninth and tenth grade high school…

  11. EAP high-level product architecture

    DEFF Research Database (Denmark)

    Guðlaugsson, Tómas Vignir; Mortensen, Niels Henrik; Sarban, Rahimullah

    2013-01-01

    EAP technology has the potential to be used in a wide range of applications. This poses the challenge to the EAP component manufacturers to develop components for a wide variety of products. Danfoss Polypower A/S is developing an EAP technology platform, which can form the basis for a variety...... of EAP technology products while keeping complexity under control. High level product architecture has been developed for the mechanical part of EAP transducers, as the foundation for platform development. A generic description of an EAP transducer forms the core of the high level product architecture...... the function of the EAP transducers to be changed, by basing the EAP transducers on a different combination of organ alternatives. A model providing an overview of the high level product architecture has been developed to support daily development and cooperation across development teams. The platform approach...

  12. Transverse colon conduit urinary diversion in patients treated with very high dose pelvic irradiation

    International Nuclear Information System (INIS)

    Ravi, R.; Dewan, A.K.; Pandey, K.K.

    1994-01-01

    Urinary diversion may be required in patients receiving pelvic irradiation for gynaecological or genitourinary cancers either as part of a planned or salvage surgical procedure or for urological complications of irradiation. Records were reviewed for 30 such patients who underwent transverse colon conduit as a primary form of urinary diversion. Most of the conduits were constructed using refluxing ureterocolic anastomoses with stents. The results showed no operative mortality. Although the procedure was associated with a complication rate of 37% and a re-operation rate of 20%, there were no bowel or urinary anastomotic leaks. The operation could be safely performed on patients with renal failure, with 83% of such patients showing normal or improved serum creatinine levels post operatively. The advantages of transverse colon conduit urinary diversion are the use of non-irradiated bowel and ureters for diversion. It is recommended as a primary form of urinary diversion in these high risk cases. (Author)

  13. Plant diversity on high elevation islands – drivers of species richness and endemism

    Directory of Open Access Journals (Sweden)

    Severin D.H. Irl

    2016-10-01

    Full Text Available High elevation islands elicit fascination because of their large array of endemic species and strong environmental gradients. First, I define a high elevation island according to geographic and environmental characteristics. Then, within this high elevation island framework, I address local disturbance effects on plant distribution, drivers of diversity and endemism on the island scale, and global patterns of treeline elevation and climate change. Locally, introduced herbivores have strong negative effects on the summit scrub of my model island La Palma (Canary Islands, while roads have unexpected positive effects on endemics. On the island scale, topography and climate drive diversity and endemism. Hotspots of endemicity are found in summit regions – a general pattern on high elevation islands. The global pattern of treeline elevation behaves quite differently on islands than on the mainland. A thorough literature review and climate projections suggest that climate change will profoundly affect oceanic island floras.

  14. Potential impacts of biomass production in the United States on biological diversity

    International Nuclear Information System (INIS)

    Cook, J.H.; Beyea, J.; Keeler, K.H.

    1991-01-01

    This paper reports that biomass could be a renewable source of energy and chemicals that would not add CO 2 to the atmosphere. It will become economically competitive as its cost decreases relative to energy costs, and biotechnology is expected to accelerate this trend by increasing biomass productivity. Pressure to slow global warming may also make biomass more attractive. Substantial dependence on biomass would entail massive changes in land use, risking serious reductions in biodiversity through destruction of habitat for native species. Forests could be managed and harvested more intensively, and virtually all arable land unsuitable for high-value agriculture or silviculture might be used to grow energy crops. The authors estimate that it would require an area equal to that farmed in 1988, about 130 million hectares, just to supply the United States with transportation fuel. Planning at micro to macro scales will be crucial to minimize the ecological impacts of producing biomass. Cropping and harvesting systems will need to provide the spatial and temporal diversity characteristics of natural ecosystems and successional sequences. To maximize habitat value for interior-dependent species, it will be essential to maintain the connectivity of the habitat network, both within biomass farms and to surrounding undisturbed areas

  15. Diet simplification selects for high gut microbial diversity and strong fermenting ability in high-altitude pikas.

    Science.gov (United States)

    Li, Huan; Qu, Jiapeng; Li, Tongtong; Wirth, Stephan; Zhang, Yanming; Zhao, Xinquan; Li, Xiangzhen

    2018-06-03

    The gut microbiota in mammals plays a key role in host metabolism and adaptation. However, relatively little is known regarding to how the animals adapts to extreme environments through regulating gut microbial diversity and function. Here, we investigated the diet, gut microbiota, short-chain fatty acid (SCFA) profiles, and cellulolytic activity from two common pika (Ochotona spp.) species in China, including Plateau pika (Ochotona curzoniae) from the Qinghai-Tibet Plateau and Daurian pika (Ochotona daurica) from the Inner Mongolia Grassland. Despite a partial diet overlap, Plateau pikas harbored lower diet diversity than Daurian pikas. Some bacteria (e.g., Prevotella and Ruminococcus) associated with fiber degradation were enriched in Plateau pikas. They harbored higher gut microbial diversity, total SCFA concentration, and cellulolytic activity than Daurian pikas. Interestingly, cellulolytic activity was positively correlated with the gut microbial diversity and SCFAs. Gut microbial communities and SCFA profiles were segregated structurally between host species. PICRUSt metagenome predictions demonstrated that microbial genes involved in carbohydrate metabolism and energy metabolism were overrepresented in the gut microbiota of Plateau pikas. Our results demonstrate that Plateau pikas harbor a stronger fermenting ability for the plant-based diet than Daurian pikas via gut microbial fermentation. The enhanced ability for utilization of plant-based diets in Plateau pikas may be partly a kind of microbiota adaptation for more energy requirements in cold and hypoxic high-altitude environments.

  16. Signal Diversity of Receptor for Advanced Glycation End Products.

    Science.gov (United States)

    Sakaguchi, Masakiyo; Kinoshita, Rie; Putranto, Endy Widya; Ruma, I Made Winarsa; Sumardika, I Wayan; Youyi, Chen; Tomonobu, Naoko; Yamamoto, Ken-Ichi; Murata, Hitoshi

    2017-12-01

    The receptor for advanced glycation end products (RAGE) is involved in inflammatory pathogenesis. It functions as a receptor to multiple ligands such as AGEs, HMGB1 and S100 proteins, activating multiple intracellular signaling pathways with each ligand binding. The molecular events by which ligand-activated RAGE controls diverse signaling are not well understood, but some progress was made recently. Accumulating evidence revealed that RAGE has multiple binding partners within the cytoplasm and on the plasma membrane. It was first pointed out in 2008 that RAGE's cytoplasmic tail is able to recruit Diaphanous-1 (Dia-1), resulting in the acquisition of increased cellular motility through Rac1/Cdc42 activation. We also observed that within the cytosol, RAGE's cytoplasmic tail behaves similarly to a Toll-like receptor (TLR4)-TIR domain, interacting with TIRAP and MyD88 adaptor molecules that in turn activate multiple downstream signals. Subsequent studies demonstrated the presence of an alternative adaptor molecule, DAP10, on the plasma membrane. The coupling of RAGE with DAP10 is critical for enhancing the RAGE-mediated survival signal. Interestingly, RAGE interaction on the membrane was not restricted to DAP10 alone. The chemotactic G-protein-coupled receptors (GPCRs) formyl peptide receptors1 and 2 (FPR1 and FPR2) also interacted with RAGE on the plasma membrane. Binding interaction between leukotriene B4 receptor 1 (BLT1) and RAGE was also demonstrated. All of the interactions affected the RAGE signal polarity. These findings indicate that functional interactions between RAGE and various molecules within the cytoplasmic area or on the membrane area coordinately regulate multiple ligand-mediated RAGE responses, leading to typical cellular phenotypes in several pathological settings. Here we review RAGE's signaling diversity, to contribute to the understanding of the elaborate functions of RAGE in physiological and pathological contexts.

  17. Grassland-Cropping Rotations: An Avenue for Agricultural Diversification to Reconcile High Production with Environmental Quality.

    Science.gov (United States)

    Lemaire, Gilles; Gastal, François; Franzluebbers, Alan; Chabbi, Abad

    2015-11-01

    A need to increase agricultural production across the world to ensure continued food security appears to be at odds with the urgency to reduce the negative environmental impacts of intensive agriculture. Around the world, intensification has been associated with massive simplification and uniformity at all levels of organization, i.e., field, farm, landscape, and region. Therefore, we postulate that negative environmental impacts of modern agriculture are due more to production simplification than to inherent characteristics of agricultural productivity. Thus by enhancing diversity within agricultural systems, it should be possible to reconcile high quantity and quality of food production with environmental quality. Intensification of livestock and cropping systems separately within different specialized regions inevitably leads to unacceptable environmental impacts because of the overly uniform land use system in intensive cereal areas and excessive N-P loads in intensive animal areas. The capacity of grassland ecosystems to couple C and N cycles through microbial-soil-plant interactions as a way for mitigating the environmental impacts of intensive arable cropping system was analyzed in different management options: grazing, cutting, and ley duration, in order to minimize trade-offs between production and the environment. We suggest that integrated crop-livestock systems are an appropriate strategy to enhance diversity. Sod-based rotations can temporally and spatially capture the benefits of leys for minimizing environmental impacts, while still maintaining periods and areas of intensive cropping. Long-term experimental results illustrate the potential of such systems to sequester C in soil and to reduce and control N emissions to the atmosphere and hydrosphere.

  18. Production of novel types of antibacterial liamocins by diverse strains of Aureobasidium pullulans grown on different culture media

    Science.gov (United States)

    Objective: The objective was to compare production of antibacterial liamocins by diverse strains of A. pullulans grown on different culture media. Results: Liamocins produced by strains of A. pullulans have potential agricultural and pharmaceutical applications as antibacterials with specificity aga...

  19. Inspiring science achievement: a mixed methods examination of the practices and characteristics of successful science programs in diverse high schools

    Science.gov (United States)

    Scogin, Stephen C.; Cavlazoglu, Baki; LeBlanc, Jennifer; Stuessy, Carol L.

    2017-08-01

    While the achievement gap in science exists in the US, research associated with our investigation reveals some high school science programs serving diverse student bodies are successfully closing the gap. Using a mixed methods approach, we identified and investigated ten high schools in a large Southwestern state that fit the definition of "highly successful, highly diverse". By conducting interviews with science liaisons associated with each school and reviewing the literature, we developed a rubric identifying specific characteristics associated with successful science programs. These characteristics and practices included setting high expectations for students, providing extensive teacher support for student learning, and utilizing student-centered pedagogy. We used the rubric to assess the successful high school science programs and compare them to other high school science programs in the state (i.e., less successful and less diverse high school science programs). Highly successful, highly diverse schools were very different in their approach to science education when compared to the other programs. The findings from this study will help schools with diverse students to strengthen hiring practices, enhance teacher support mechanisms, and develop student-focused strategies in the classroom that increase science achievement.

  20. Genetic diversity in wheat germplasm collections from Balochistan province of Pakistan

    International Nuclear Information System (INIS)

    Khan, A.A.; Iqbal, A.; Awan, F.S.; Khan, I.A.

    2010-01-01

    Productivity of wheat varieties being bred for the last many years is stagnant in Pakistan, apparently because of the narrowed genetic base of their parental lines. As a part of the national wheat germplasm characterization programme, we examined genetic diversity among 75 accessions of wheat using RAPD markers and assessed the relationship and genetic distance between them. The accessions surveyed were comprised of land race populations of Triticum aestivum L., collected from various districts of the Balochistan province of Pakistan, which is considered a reservoir of genetic diversity, particularly for wheat. The genetic similarity revealed by RAPD markers among the wheat accessions was medium to high. The accessions collected from Sibi and Pishin districts had the greatest similarity. The polymorphism revealed in the wheat accessions, appeared to be distributed with the location of collections. The high degree of similarity even among the presumably land race material emphasizes the need for the expansion of germplasm resources and development of wheat varieties with diverse genetic background, which could substantiate the wheat breeding programmes to increase its productivity. (author)

  1. The Impact of a Culturally Diverse Workforce on Firms’ Revenues and Productivity : An Empirical Investigation on Germany

    NARCIS (Netherlands)

    Brunow, Stephan; Nijkamp, Peter

    There is evidence from the literature that firms enjoy higher productivity levels, when the workforce employed is culturally more diverse. It is an open question whether this gain is utilized to shift the supply curve and set lower prices in order to achieve a higher demand and possibly higher

  2. Managing gender diversity in healthcare: getting it right.

    Science.gov (United States)

    Vanderbroeck, Paul; Wasserfallen, Jean-Blaise

    2017-02-06

    Purpose Diversity, notably gender diversity, is growing in health care, both at the level of teams and the level of organizations. This paper aims to describe the challenges for team leaders and leaders of organizations to manage this diversity. The authors believe that more could be done to help leaders master these challenges in a way that makes diverse teams and organizations more productive. Design/methodology/approach Drawing on previously published research, using gender diversity as an example, the paper first describes how diversity can both have a positive and a negative influence on team productivity. Next, it describes the challenge of gender diversity at an organizational level, using Switzerland as an example. Findings The first part of the paper espouses the causes of gender diversity, undoes some of the myths surrounding diversity and presents a model for effective management of diversity in teams. The second part looks at gender diversity at an organizational level. Drawing from sources inside and outside healthcare, the effects of the "leaking pipeline", "glass wall" and "glass ceiling" that prevent health-care organizations from leveraging the potential of female talent are discussed. Practical implications The authors propose a model developed for intercultural teamwork as a framework for leveraging gender diversity for better team productivity. Proposals are offered to health-care organizations on how they can tip the gender balance at senior levels into their favor, so as to get the maximum benefit from the available talent. Originality/value Applying the "how to" ideas and recommendations from this general review will help leaders of health-care organizations gain a better return on investment from their talent development as well as to increase the productivity of their workforce by a better use of diverse talent.

  3. Maize cultivar performance under diverse organic production systems

    Science.gov (United States)

    Maize cultivar performance can vary widely among different production systems. The need for high-performing hybrids for organic systems with wide adaptation to various macroenvironments is becoming increasingly important. The goal of this study was to characterize inbred lines developed by distinc...

  4. Microbial diversity in raw milk and traditional fermented dairy products (Hurood cheese and Jueke) from Inner Mongolia, China.

    Science.gov (United States)

    Gao, M L; Hou, H M; Teng, X X; Zhu, Y L; Hao, H S; Zhang, G L

    2017-03-08

    Hurood cheese (HC) and Jueke (Jk) are 2 traditional fermented dairy products produced from raw milk (RM) in the Inner Mongolia region of China. They have a long history of production and consumption. The microbial compositions of RM, HC, and Jk vary greatly, and are influenced by their geographical origins and unique processing methods. In this study, 2 batches of RM, HC, and Jk samples were collected (April and August 2015) from the Zhenglan Banner, a region located in the southern part of Inner Mongolian belonging to the Xilingol league prefecture. The bacterial and fungal diversities of the samples were determined by 16S rRNA and 18S rRNA gene sequence analysis, respectively. A total of 112 bacterial and 30 fungal sequences were identified, with Firmicutes and Ascomycota being the predominant phyla for bacteria and fungi, respectively. Lactococcus and Lactobacillus were identified as the main bacterial genera, whereas Kluyveromyces was the predominant fungus identified in the 3 dairy products. Different bacterial and fungal compositions were observed in RM, HC, and Jk samples collected at different times. These results suggested that time of production may be an important factor influencing the microbial diversity present in RM, HC, and Jk.

  5. High genetic diversity in the coat protein and 3' untranslated regions

    Indian Academy of Sciences (India)

    The 3′ terminal region consisting of the coat protein (CP) coding sequence and 3′ untranslated region (3′UTR) was cloned and sequenced from seven isolates. Sequence comparisons revealed considerable genetic diversity among the isolates in their CP and 3′UTR, making CdMV one of the highly variable members ...

  6. High purity heavy water production: need for total organic carbon determination in process water streams

    International Nuclear Information System (INIS)

    Ayushi; Kumar, Sangita D.; Reddy, A.V.R.; Vithal, G.K.

    2009-01-01

    In recent times, demand for high purity heavy water (99.98% pure) in industries and laboratories has grown by manifold. Its application started in nuclear industry with the design of CANDU reactor, which uses natural uranium as fuel. In this reactor the purest grade of heavy water is used as the moderator and the primary coolant. Diverse industrial applications like fibre optics, medicine, semiconductors etc. use high purity heavy water extensively to achieve better performance of the specific material. In all these applications there is a stringent requirement that the total organic carbon content (TOC) of high purity heavy water should be very low. This is because the presence of TOC can lead to adverse interactions in different applications. To minimize the TOC content in the final product there is a need to monitor and control the TOC content at each and every stage of heavy water production. Hence a simple, rapid and accurate method was developed for the determination of TOC content in process water samples. The paper summarizes the results obtained for the TOC content in the water samples collected from process streams of heavy water production plant. (author)

  7. Unusually high genetic diversity in COI sequences of Chimarra obscura (Trichoptera: Philopotamidae)

    Science.gov (United States)

    Chimarra obscura (Walker 1852) is a philopotamid caddisfly found throughout much of North America. Using the COI DNA barcode locus, we have found unexpectedly high amounts of genetic diversity and distances within C. obscura. Of the approximately 150 specimens sampled, we have fo...

  8. Genomic Diversity in the Genus of Aspergillus

    DEFF Research Database (Denmark)

    Rasmussen, Jane Lind Nybo

    , sections and genus of Aspergillus. The work uncovers a large genomic diversity across all studied groups of species. The genomic diversity was especially evident on the section level, where the proteins shared by all species only represents ⇠55% of the proteome. This number decreases even further, to 38......, sections Nigri, Usti and Cavericolus, clade Tubingensis, and species A. niger. It lastly uses these results to predict genetic traits that take part in fungal speciation. Within a few years the Aspergillus whole-genus sequencing project will have published all currently-accepted Aspergillus genomes......Aspergillus is a highly important genus of saprotrophic filamentous fungi. It is a very diverse genus that is inextricably intertwined with human a↵airs on a daily basis, holding species relevant to plant and human pathology, enzyme and bulk chemistry production, food and beverage biotechnology...

  9. High bacterial diversity of biological soil crusts in water tracks over permafrost in the high arctic polar desert.

    Science.gov (United States)

    Steven, Blaire; Lionard, Marie; Kuske, Cheryl R; Vincent, Warwick F

    2013-01-01

    In this study we report the bacterial diversity of biological soil crusts (biocrusts) inhabiting polar desert soils at the northern land limit of the Arctic polar region (83° 05 N). Employing pyrosequencing of bacterial 16S rRNA genes this study demonstrated that these biocrusts harbor diverse bacterial communities, often as diverse as temperate latitude communities. The effect of wetting pulses on the composition of communities was also determined by collecting samples from soils outside and inside of permafrost water tracks, hill slope flow paths that drain permafrost-affected soils. The intermittent flow regime in the water tracks was correlated with altered relative abundance of phylum level taxonomic bins in the bacterial communities, but the alterations varied between individual sampling sites. Bacteria related to the Cyanobacteria and Acidobacteria demonstrated shifts in relative abundance based on their location either inside or outside of the water tracks. Among cyanobacterial sequences, the proportion of sequences belonging to the family Oscillatoriales consistently increased in relative abundance in the samples from inside the water tracks compared to those outside. Acidobacteria showed responses to wetting pulses in the water tracks, increasing in abundance at one site and decreasing at the other two sites. Subdivision 4 acidobacterial sequences tended to follow the trends in the total Acidobacteria relative abundance, suggesting these organisms were largely responsible for the changes observed in the Acidobacteria. Taken together, these data suggest that the bacterial communities of these high latitude polar biocrusts are diverse but do not show a consensus response to intermittent flow in water tracks over high Arctic permafrost.

  10. Some like it high! Phylogenetic diversity of high-elevation cyanobacterial community from biological soil crusts of Western Himalaya.

    Czech Academy of Sciences Publication Activity Database

    Čapková, K.; Hauer, T.; Řeháková, Klára; Doležal, J.

    2016-01-01

    Roč. 71, č. 1 (2016), s. 113-123 ISSN 0095-3628 Institutional support: RVO:60077344 Keywords : soil crusts * cyanobacterial diversity * Western Himalayas * high-elevation * desert * phosphorus Subject RIV: EH - Ecology, Behaviour Impact factor: 3.630, year: 2016

  11. Ethnic diversity and employment growth in English cities.

    Science.gov (United States)

    Lee, Neil

    2011-01-01

    There are many reasons why cities with diverse populations may grow faster. Ethnic diversity might attract human capital, tourists or firms, increase productivity through diverse approaches to problem-solving or ethnic minority entrepreneurship. Yet there are also reasons to believe that diversity could be harmful, by leading to sub-optimal provision of public goods or reducing trust or social capital. Or it may be irrelevant, being merely a proxy for class. A number of studies have shown both positive and negative relationships between diversity and growth, using a range of different measures for "diversity." This paper asks two questions: have more diverse English cities grown faster? And does measurement matter: is it important to have a multinational population or an ethnically diverse one? To answer these questions, in this paper a range of models are estimated for employment growth for 53 English cities between 1981 and 2001. The evidence suggests that cities with a high proportion of their populations born abroad in 1981 grew faster in the subsequent 10 years. Neither diversity by country of birth nor ethnic diversity is significant in the period 1991-2001. However, when variables accounting for both are included together, it appears that cities with a large number of migrants saw higher employment growth in the 1990s, but that ethnically diverse cities were less successful. The results presented here suggest that considerable attention needs to be paid to the variable used to indicate "diversity" in these studies and that the impact of diversity varies according to nature of the groups any indicator for "diversity" is representing.

  12. High diversity of genogroup I picobirnaviruses in mammals

    Directory of Open Access Journals (Sweden)

    Patrick CY Woo

    2016-11-01

    Full Text Available In a molecular epidemiology study using 791 fecal samples collected from different terrestrial and marine mammals in Hong Kong, genogroup I picobirnaviruses (PBVs were positive by RT-PCR targeting the partial RdRp gene in specimens from 5 cattle, 6 monkeys, 17 horses, 9 pigs, 1 rabbit, 1 dog and 12 California sea lions, with 11, 9, 23, 17, 1, 1 and 15 sequence types in the positive specimens from the corresponding animals, respectively. Phylogenetic analysis showed that the PBV sequences from each kind of animal were widely distributed in the whole tree with high diversity, sharing 47.4 to 89.0% nucleotide identities with other genogroup I PBV strains based on the partial RdRp gene. Nine complete segments 1 (viral loads 1.7×104 to 5.9×106/ml and 15 segments 2 (viral loads 4.1×103 to 1.3×106/ml of otarine PBVs from fecal samples serially collected from California sea lions were sequenced. In the two phylogenetic trees constructed using ORF2 and ORF3 of segment 1, the nine segment 1 sequences were clustered into four distinct clades (C1 to C4. In the tree constructed using RdRp gene of segment 2, the 15 segment 2 sequences were clustered into nine distinct clades (R1 to R9. In four sea lions, PBVs were detected in two different years, with the same segment 1 clade (C3 present in two consecutive years from one sea lion and different clades present in different years from three sea lions. A high diversity of PBVs was observed in a variety of terrestrial and marine mammals. Multiple sequence types with significant differences, representing multiple strains of PBV, were present in the majority of PBV-positive samples from different kinds of animals.

  13. Multilocus sequence analysis (MLSA) of Bradyrhizobium strains: revealing high diversity of tropical diazotrophic symbiotic bacteria.

    Science.gov (United States)

    Delamuta, Jakeline Renata Marçon; Ribeiro, Renan Augusto; Menna, Pâmela; Bangel, Eliane Villamil; Hungria, Mariangela

    2012-04-01

    Symbiotic association of several genera of bacteria collectively called as rhizobia and plants belonging to the family Leguminosae (=Fabaceae) results in the process of biological nitrogen fixation, playing a key role in global N cycling, and also bringing relevant contributions to the agriculture. Bradyrhizobium is considered as the ancestral of all nitrogen-fixing rhizobial species, probably originated in the tropics. The genus encompasses a variety of diverse bacteria, but the diversity captured in the analysis of the 16S rRNA is often low. In this study, we analyzed twelve Bradyrhizobium strains selected from previous studies performed by our group for showing high genetic diversity in relation to the described species. In addition to the 16S rRNA, five housekeeping genes (recA, atpD, glnII, gyrB and rpoB) were analyzed in the MLSA (multilocus sequence analysis) approach. Analysis of each gene and of the concatenated housekeeping genes captured a considerably higher level of genetic diversity, with indication of putative new species. The results highlight the high genetic variability associated with Bradyrhizobium microsymbionts of a variety of legumes. In addition, the MLSA approach has proved to represent a rapid and reliable method to be employed in phylogenetic and taxonomic studies, speeding the identification of the still poorly known diversity of nitrogen-fixing rhizobia in the tropics.

  14. Microbial diversity arising from thermodynamic constraints

    Science.gov (United States)

    Großkopf, Tobias; Soyer, Orkun S

    2016-01-01

    The microbial world displays an immense taxonomic diversity. This diversity is manifested also in a multitude of metabolic pathways that can utilise different substrates and produce different products. Here, we propose that these observations directly link to thermodynamic constraints that inherently arise from the metabolic basis of microbial growth. We show that thermodynamic constraints can enable coexistence of microbes that utilise the same substrate but produce different end products. We find that this thermodynamics-driven emergence of diversity is most relevant for metabolic conversions with low free energy as seen for example under anaerobic conditions, where population dynamics is governed by thermodynamic effects rather than kinetic factors such as substrate uptake rates. These findings provide a general understanding of the microbial diversity based on the first principles of thermodynamics. As such they provide a thermodynamics-based framework for explaining the observed microbial diversity in different natural and synthetic environments. PMID:27035705

  15. Microbial diversity arising from thermodynamic constraints.

    Science.gov (United States)

    Großkopf, Tobias; Soyer, Orkun S

    2016-11-01

    The microbial world displays an immense taxonomic diversity. This diversity is manifested also in a multitude of metabolic pathways that can utilise different substrates and produce different products. Here, we propose that these observations directly link to thermodynamic constraints that inherently arise from the metabolic basis of microbial growth. We show that thermodynamic constraints can enable coexistence of microbes that utilise the same substrate but produce different end products. We find that this thermodynamics-driven emergence of diversity is most relevant for metabolic conversions with low free energy as seen for example under anaerobic conditions, where population dynamics is governed by thermodynamic effects rather than kinetic factors such as substrate uptake rates. These findings provide a general understanding of the microbial diversity based on the first principles of thermodynamics. As such they provide a thermodynamics-based framework for explaining the observed microbial diversity in different natural and synthetic environments.

  16. The Diversity and Productivity of Indigenous Forage in Former Limestone Mining Quarry in Karst Mountain of Southern Gombong, Central Java Indonesia

    Directory of Open Access Journals (Sweden)

    Doso Sarwanto

    2015-05-01

    Full Text Available Indonesia is a country that has a lot of limestone mountains, covering 15.4 million hectares. Limestone mountains have strategic functions as limestone is used as building materials and as raw material in cement industry. Therefore, limestone mining quarry in various areas of limestone mountains in Indonesia is increasingly widespread. The biggest negative impact of limestone mining is the formed open land which is abandoned and unutilized. Changes in the ecosystem will lead to the reduced levels of diversity and productivity of indigenous forage which will ultimately reduce the performance and development of ruminants livestock kept by farmers in the mountainous region of limestone. This study aims to determine the diversity and productivity of indigenous forage on former limestone mining quarry in limestone mountains of southern Gombong. The research was conducted through survey by identifying and measuring the forage production of sample plots assigned purposively. Location of the study was divided into three categories, mild, moderate and heavy mining. Results showed that soil fertility levels in open fields of former limestone mining in southern Gombong mountains are low with total N content of 0.049 - 0.141%, total P2O5 of 0.067 - 0.133% and total K2O of 0.086 - 0.100%. The diversity of indigenous forage on mild mining was more diverse than that of moderate and heavy mining, i.e. 13 species comprising 7 grass species, 2 legumes species, and 4 species of shrubs. The most dominant species in all mining categories are Cynodon dactylon, Imperata cylindrica, Ageratum conyzoides and Mikania micrantha. The results also showed that in the open land of mild mining had the highest production of fresh and dry matter compared to that of moderate and severe mining

  17. High variability of dung beetle diversity patterns at four mountains of the Trans-Mexican Volcanic Belt

    Directory of Open Access Journals (Sweden)

    Alfonsina Arriaga-Jiménez

    2018-02-01

    Full Text Available Insect diversity patterns of high mountain ecosystems remain poorly studied in the tropics. Sampling dung beetles of the subfamilies Aphodiinae, Scarabaeinae, and Geotrupinae was carried out at four volcanoes in the Trans-Mexican Volcanic Belt (TMVB in the Mexican transition zone at 2,700 and 3,400 MASL, and on the windward and leeward sides. Sampling units represented a forest–shrubland–pasture (FSP mosaic typical of this mountain region. A total of 3,430 individuals of 29 dung beetle species were collected. Diversity, abundance and compositional similarity (CS displayed a high variability at all scales; elevation, cardinal direction, or FSP mosaics did not show any patterns of higher or lower values of those measures. The four mountains were different regarding dispersion patterns and taxonomic groups, both for species and individuals. Onthophagus chevrolati dominated all four mountains with an overall relative abundance of 63%. CS was not related to distance among mountains, but when O. chevrolati was excluded from the analysis, CS values based on species abundance decreased with increasing distance. Speciation, dispersion, and environmental instability are suggested as the main drivers of high mountain diversity patterns, acting together at different spatial and temporal scales. Three species new to science were collected (>10% of all species sampled. These discoveries may indicate that speciation rate is high among these volcanoes—a hypothesis that is also supported by the elevated number of collected species with a restricted montane distribution. Dispersion is an important factor in driving species composition, although naturally limited between high mountains; horizontal colonization events at different time scales may best explain the observed species composition in the TMVB, complemented by vertical colonization events to a lesser extent. Environmental instability may be the main factor causing the high variability of diversity

  18. High variability of dung beetle diversity patterns at four mountains of the Trans-Mexican Volcanic Belt.

    Science.gov (United States)

    Arriaga-Jiménez, Alfonsina; Rös, Matthias; Halffter, Gonzalo

    2018-01-01

    Insect diversity patterns of high mountain ecosystems remain poorly studied in the tropics. Sampling dung beetles of the subfamilies Aphodiinae, Scarabaeinae, and Geotrupinae was carried out at four volcanoes in the Trans-Mexican Volcanic Belt (TMVB) in the Mexican transition zone at 2,700 and 3,400 MASL, and on the windward and leeward sides. Sampling units represented a forest-shrubland-pasture (FSP) mosaic typical of this mountain region. A total of 3,430 individuals of 29 dung beetle species were collected. Diversity, abundance and compositional similarity (CS) displayed a high variability at all scales; elevation, cardinal direction, or FSP mosaics did not show any patterns of higher or lower values of those measures. The four mountains were different regarding dispersion patterns and taxonomic groups, both for species and individuals. Onthophagus chevrolati dominated all four mountains with an overall relative abundance of 63%. CS was not related to distance among mountains, but when O. chevrolati was excluded from the analysis, CS values based on species abundance decreased with increasing distance. Speciation, dispersion, and environmental instability are suggested as the main drivers of high mountain diversity patterns, acting together at different spatial and temporal scales. Three species new to science were collected (>10% of all species sampled). These discoveries may indicate that speciation rate is high among these volcanoes-a hypothesis that is also supported by the elevated number of collected species with a restricted montane distribution. Dispersion is an important factor in driving species composition, although naturally limited between high mountains; horizontal colonization events at different time scales may best explain the observed species composition in the TMVB, complemented by vertical colonization events to a lesser extent. Environmental instability may be the main factor causing the high variability of diversity and abundance patterns

  19. Quantification and valuation of ecosystem services in diverse production systems for informed decision-making

    DEFF Research Database (Denmark)

    Ghaley, Bhim Bahadur; Vesterdal, Lars; Porter, John Roy

    2014-01-01

    The empirical evidence of decline in ecosystem services (ES) over the last century has reinforced the call for ES quantification, monitoring and valuation. Usually, only provisioning ES are marketable and accounted for, whereas regulating, supporting and cultural ES are typically non-marketable a......The empirical evidence of decline in ecosystem services (ES) over the last century has reinforced the call for ES quantification, monitoring and valuation. Usually, only provisioning ES are marketable and accounted for, whereas regulating, supporting and cultural ES are typically non......-marketable and overlooked in connection with land-use or management decisions. The objective of this study was to quantify and value total ES (marketable and non-marketable) of diverse production systems and management intensities in Denmark to provide a basis for decisions based on economic values. The production systems...

  20. Bacillus subtilis genome diversity.

    Science.gov (United States)

    Earl, Ashlee M; Losick, Richard; Kolter, Roberto

    2007-02-01

    Microarray-based comparative genomic hybridization (M-CGH) is a powerful method for rapidly identifying regions of genome diversity among closely related organisms. We used M-CGH to examine the genome diversity of 17 strains belonging to the nonpathogenic species Bacillus subtilis. Our M-CGH results indicate that there is considerable genetic heterogeneity among members of this species; nearly one-third of Bsu168-specific genes exhibited variability, as measured by the microarray hybridization intensities. The variable loci include those encoding proteins involved in antibiotic production, cell wall synthesis, sporulation, and germination. The diversity in these genes may reflect this organism's ability to survive in diverse natural settings.

  1. Soil bacterial diversity in degraded and restored lands of Northeast Brazil.

    Science.gov (United States)

    Araújo, Ademir Sérgio Ferreira; Borges, Clovis Daniel; Tsai, Siu Mui; Cesarz, Simone; Eisenhauer, Nico

    2014-11-01

    Land degradation deteriorates biological productivity and affects environmental, social, and economic sustainability, particularly so in the semi-arid region of Northeast Brazil. Although some studies exist reporting gross measures of soil microbial parameters and processes, limited information is available on how land degradation and restoration strategies influence the diversity and composition of soil microbial communities. In this study we compare the structure and diversity of bacterial communities in degraded and restored lands in Northeast Brazil and determine the soil biological and chemical properties influencing bacterial communities. We found that land degradation decreased the diversity of soil bacteria as indicated by both reduced operational taxonomic unit (OTU) richness and Shannon index. Soils under native vegetation and restoration had significantly higher bacterial richness and diversity than degraded soils. Redundancy analysis revealed that low soil bacterial diversity correlated with a high respiratory quotient, indicating stressed microbial communities. By contrast, soil bacterial communities in restored land positively correlated with high soil P levels. Importantly, however, we found significant differences in the soil bacterial community composition under native vegetation and in restored land, which may indicate differences in their functioning despite equal levels of bacterial diversity.

  2. Biodiversity increases the resistance of ecosystem productivity to climate extremes.

    Science.gov (United States)

    Isbell, Forest; Craven, Dylan; Connolly, John; Loreau, Michel; Schmid, Bernhard; Beierkuhnlein, Carl; Bezemer, T Martijn; Bonin, Catherine; Bruelheide, Helge; de Luca, Enrica; Ebeling, Anne; Griffin, John N; Guo, Qinfeng; Hautier, Yann; Hector, Andy; Jentsch, Anke; Kreyling, Jürgen; Lanta, Vojtěch; Manning, Pete; Meyer, Sebastian T; Mori, Akira S; Naeem, Shahid; Niklaus, Pascal A; Polley, H Wayne; Reich, Peter B; Roscher, Christiane; Seabloom, Eric W; Smith, Melinda D; Thakur, Madhav P; Tilman, David; Tracy, Benjamin F; van der Putten, Wim H; van Ruijven, Jasper; Weigelt, Alexandra; Weisser, Wolfgang W; Wilsey, Brian; Eisenhauer, Nico

    2015-10-22

    It remains unclear whether biodiversity buffers ecosystems against climate extremes, which are becoming increasingly frequent worldwide. Early results suggested that the ecosystem productivity of diverse grassland plant communities was more resistant, changing less during drought, and more resilient, recovering more quickly after drought, than that of depauperate communities. However, subsequent experimental tests produced mixed results. Here we use data from 46 experiments that manipulated grassland plant diversity to test whether biodiversity provides resistance during and resilience after climate events. We show that biodiversity increased ecosystem resistance for a broad range of climate events, including wet or dry, moderate or extreme, and brief or prolonged events. Across all studies and climate events, the productivity of low-diversity communities with one or two species changed by approximately 50% during climate events, whereas that of high-diversity communities with 16-32 species was more resistant, changing by only approximately 25%. By a year after each climate event, ecosystem productivity had often fully recovered, or overshot, normal levels of productivity in both high- and low-diversity communities, leading to no detectable dependence of ecosystem resilience on biodiversity. Our results suggest that biodiversity mainly stabilizes ecosystem productivity, and productivity-dependent ecosystem services, by increasing resistance to climate events. Anthropogenic environmental changes that drive biodiversity loss thus seem likely to decrease ecosystem stability, and restoration of biodiversity to increase it, mainly by changing the resistance of ecosystem productivity to climate events.

  3. Unraveling the impact of workforce age diversity on labor productivity : The moderating role of firm size and job security

    NARCIS (Netherlands)

    De Meulenaere, Kim; Boone, Christophe; Buyl, T.P.L.

    Previous literature has suggested both positive and negative effects of age diversity on labor productivity: positive because of the potential knowledge complementarities between employees of different ages and negative because of the age-related value differences that might reduce cohesion and

  4. A robust, simple genotyping-by-sequencing (GBS approach for high diversity species.

    Directory of Open Access Journals (Sweden)

    Robert J Elshire

    Full Text Available Advances in next generation technologies have driven the costs of DNA sequencing down to the point that genotyping-by-sequencing (GBS is now feasible for high diversity, large genome species. Here, we report a procedure for constructing GBS libraries based on reducing genome complexity with restriction enzymes (REs. This approach is simple, quick, extremely specific, highly reproducible, and may reach important regions of the genome that are inaccessible to sequence capture approaches. By using methylation-sensitive REs, repetitive regions of genomes can be avoided and lower copy regions targeted with two to three fold higher efficiency. This tremendously simplifies computationally challenging alignment problems in species with high levels of genetic diversity. The GBS procedure is demonstrated with maize (IBM and barley (Oregon Wolfe Barley recombinant inbred populations where roughly 200,000 and 25,000 sequence tags were mapped, respectively. An advantage in species like barley that lack a complete genome sequence is that a reference map need only be developed around the restriction sites, and this can be done in the process of sample genotyping. In such cases, the consensus of the read clusters across the sequence tagged sites becomes the reference. Alternatively, for kinship analyses in the absence of a reference genome, the sequence tags can simply be treated as dominant markers. Future application of GBS to breeding, conservation, and global species and population surveys may allow plant breeders to conduct genomic selection on a novel germplasm or species without first having to develop any prior molecular tools, or conservation biologists to determine population structure without prior knowledge of the genome or diversity in the species.

  5. Maintaining High Challenge and High Support for Diverse Learners

    Science.gov (United States)

    Athanases, Steven

    2012-01-01

    As teachers, schools and school leaders work to better prepare California's culturally and linguistically diverse students, methods for doing so vary widely. One approach prioritizes safe spaces, welcoming environments, well-structured routines--school and classroom culture features essential for students' well-being. A second key priority, often…

  6. Trends in Ph.D. Productivity and Diversity in Top-50 U.S. Chemistry Departments: An Institutional Analysis

    Science.gov (United States)

    Laursen, Sandra L.; Weston, Timothy J.

    2014-01-01

    The education of doctoral chemists contributes to the chemical research enterprise and thus to innovation as an engine of the economy. This quantitative analysis describes trends in the production and diversity of chemistry Ph.D. degrees in the top-50 U.S. Ph.D.-granting departments in the past two decades. Time series data for individual…

  7. High phylogenetic diversity is preserved in species-poor high-elevation temperate moth assemblages

    NARCIS (Netherlands)

    Zou, Yi; Sang, Weiguo; Hausmann, Axel; Axmacher, Jan Christoph

    2016-01-01

    Understanding the diversity and composition of species assemblages and identifying underlying biotic and abiotic determinants represent great ecological challenges. Addressing some of these issues, we investigated the α-diversity and phylogenetic composition of species-rich geometrid moth

  8. Genetic diversity of Colombian sheep by microsatellite markers

    Directory of Open Access Journals (Sweden)

    Ricardo Ocampo

    2016-03-01

    Full Text Available In Colombia the sheep production systems are managed under extensive conditions and mainly correspond to peasant production systems so their genetic management has led to increased homozygosity and hence productivity loss. The aim of this study was to determine the genetic diversity in 549 individuals corresponding to 13 sheep breeds in Colombia, using a panel of 11 microsatellite molecular markers. One hundred and fifty seven alleles were found (average of 14.27 alleles/locus, with a range of observed and expected heterozygosity from 0.44 to 0.84 and 0.67 to 0.86, respectively. Thirty-three of 143 Hardy Weinberg tests performed showed significant deviations (p < 0.05 due to a general lack of heterozygous individuals. The Fis ranged from 0.01 in Corriedale to 0.15 for the Persian Black Head breed, suggesting that there are presenting low to moderate levels of inbreeding. Overall, Colombian sheep showed high levels of genetic diversity which is very important for future selection and animal breeding programs.

  9. Genetic diversity affects colony survivorship in commercial honey bee colonies

    Science.gov (United States)

    Tarpy, David R.; vanEngelsdorp, Dennis; Pettis, Jeffrey S.

    2013-08-01

    Honey bee ( Apis mellifera) queens mate with unusually high numbers of males (average of approximately 12 drones), although there is much variation among queens. One main consequence of such extreme polyandry is an increased diversity of worker genotypes within a colony, which has been shown empirically to confer significant adaptive advantages that result in higher colony productivity and survival. Moreover, honey bees are the primary insect pollinators used in modern commercial production agriculture, and their populations have been in decline worldwide. Here, we compare the mating frequencies of queens, and therefore, intracolony genetic diversity, in three commercial beekeeping operations to determine how they correlate with various measures of colony health and productivity, particularly the likelihood of queen supersedure and colony survival in functional, intensively managed beehives. We found the average effective paternity frequency ( m e ) of this population of honey bee queens to be 13.6 ± 6.76, which was not significantly different between colonies that superseded their queen and those that did not. However, colonies that were less genetically diverse (headed by queens with m e ≤ 7.0) were 2.86 times more likely to die by the end of the study when compared to colonies that were more genetically diverse (headed by queens with m e > 7.0). The stark contrast in colony survival based on increased genetic diversity suggests that there are important tangible benefits of increased queen mating number in managed honey bees, although the exact mechanism(s) that govern these benefits have not been fully elucidated.

  10. High levels of diversity characterize mandrill (Mandrillus sphinx) Mhc-DRB sequences.

    Science.gov (United States)

    Abbott, Kristin M; Wickings, E Jean; Knapp, Leslie A

    2006-08-01

    The major histocompatibility complex (MHC) is highly polymorphic in most primate species studied thus far. The rhesus macaque (Macaca mulatta) has been studied extensively and the Mhc-DRB region demonstrates variability similar to humans. The extent of MHC diversity is relatively unknown for other Old World monkeys (OWM), especially among genera other than Macaca. A molecular survey of the Mhc-DRB region in mandrills (Mandrillus sphinx) revealed extensive variability, suggesting that other OWMs may also possess high levels of Mhc-DRB polymorphism. In the present study, 33 Mhc-DRB loci were identified from only 13 animals. Eleven were wild-born and presumed to be unrelated and two were captive-born twins. Two to seven different sequences were identified for each individual, suggesting that some mandrills may have as many as four Mhc-DRB loci on a single haplotype. From these sequences, representatives of at least six Mhc-DRB loci or lineages were identified. As observed in other primates, some new lineages may have arisen through the process of gene conversion. These findings indicate that mandrills have Mhc-DRB diversity not unlike rhesus macaques and humans.

  11. [Study on Microbial Diversity of Peri-implantitis Subgingival by High-throughput Sequencing].

    Science.gov (United States)

    Li, Zhi-jie; Wang, Shao-guo; Li, Yue-hong; Tu, Dong-xiang; Liu, Shi-yun; Nie, Hong-bing; Li, Zhi-qiang; Zhang, Ju-mei

    2015-07-01

    To study microbial diversity of peri-implantitis subgingival with high-throughput sequencing, and investigate microbiological etiology of peri-implantitis. Subgingival plaques were sampled from the patients with peri-implantitis (D group) and non-peri-implantitis subjects (N group). The microbiological diversity of the subgingival plaques was detected by sequencing V4 region of 16S rRNA with Illumina Miseq platform. The diversity of the community structure was analyzed using Mothur software. A total of 156 507 gene sequences were detected in nine samples and 4 402 operational taxonomic units (OTUs) were found. Selenomonas, Pseudomonas, and Fusobacterium were dominant bacteria in D group, while Fusobacterium, Veillonella and Streptococcus were dominant bacteria in N group. Differences between peri-implantitis and non-peri-implantitis bacterial communities were observed at all phylogenetic levels by LEfSe, which was also found in PcoA test. The occurrence of peri-implantitis is not only related to periodontitis pathogenic microbe, but also related with the changes of oral microbial community structure. Treponema, Herbaspirillum, Butyricimonas and Phaeobacte may be closely related to the occurrence and development of peri-implantitis.

  12. The genotypic diversity and lipase production of some thermophilic bacilli from different genera

    Directory of Open Access Journals (Sweden)

    Melih Koc

    2015-12-01

    Full Text Available Abstract Thermophilic 32 isolates and 20 reference bacilli were subjected to Rep-PCR and ITS-PCR fingerprinting for determination of their genotypic diversity, before screening lipase activities. By these methods, all the isolates and references could easily be differentiated up to subspecies level from each other. In screening assay, 11 isolates and 7 references were found to be lipase producing. Their extracellular lipase activities were measured quantitatively by incubating in both tributyrin and olive oil broths at 60 °C and pH 7.0. During the 24, 48 and 72-h period of incubation, the changes in the lipase activities, culture absorbance, wet weight of biomass and pH were all measured. The activity was determined by using pNPB in 50 mM phosphate buffer at pH 7.0 at 60 °C. The lipase production of the isolates in olive oil broths varied between 0.008 and 0.052, whereas these values were found to be 0.002-0.019 (U/mL in the case of tyributyrin. For comparison, an index was established by dividing the lipase activities to cell biomass (U/mg. The maximum thermostable lipase production was achieved by the isolates F84a, F84b, and G. thermodenitrificans DSM 465T (0.009, 0.008 and 0.008 U/mg within olive oil broth, whereas G. stearothermophilus A113 displayed the highest lipase activity than its type strain in tyributyrin. Therefore, as some of these isolates displayed higher activities in comparison to references, new lipase producing bacilli were determined by presenting their genotypic diversity with DNA fingerprinting techniques.

  13. Genetic diversity of naturalized cacao (Theobroma cacao L.) in Puerto Rico

    Science.gov (United States)

    Identification of genetically diverse cacao with disease resistance, high productivity and desirable organoleptic traits is vitally important to the agricultural crop’s long-term sustainability. Environmental changes, pests and diseases as well as nation’s sovereign property rights have led to a de...

  14. Relationships between the use of Embden Meyerhof pathway (EMP) or Phosphoketolase pathway (PKP) and lactate production capabilities of diverse Lactobacillus reuteri strains.

    Science.gov (United States)

    Burgé, Grégoire; Saulou-Bérion, Claire; Moussa, Marwen; Allais, Florent; Athes, Violaine; Spinnler, Henry-Eric

    2015-10-01

    The aims of this study is to compare the growth and glucose metabolism of three Lactobacillus reuteri strains (i.e. DSM 20016, DSM 17938, and ATCC 53608) which are lactic acid bacteria of interest used for diverse applications such as probiotics implying the production of biomass, or for the production of valuable chemicals (3-hydroxypropionaldehyde, 3-hydroxypropionic acid, 1,3-propanediol). However, the physiological diversity inside the species, even for basic metabolisms, like its capacity of acidification or glucose metabolism, has not been studied yet. In the present work, the growth and metabolism of three strains representative of the species diversity have been studied in batch mode. The strains were compared through characterization of growth kinetics and evaluation of acidification kinetics, substrate consumption and product formation. The results showed significant differences between the three strains which may be explained, at least in part, by variations in the distribution of carbon source between two glycolytic pathways during the bacterial growth: the phosphoketolase or heterolactic pathway (PKP) and the Embden-Meyerhof pathway (EMP). It was also shown that, in the context of obtaining a large amount of biomass, DSM 20016 and DSM 17938 strains were the most effective in terms of growth kinetics. The DSM 17938 strain, which shows the more significant metabolic shift from EMP to PKP when the pH decreases, is more effective for lactate production.

  15. The impact of group composition and attitudes towards diversity on anticipated outcomes of diversity in groups

    NARCIS (Netherlands)

    van Oudenhoven-van der Zee, Karen; Paulus, Paul; Vos, Menno; Parthasarathy, Niveditha

    In two studies, students evaluated group pictures of workgroups of varying ethnic and gender composition with respect to anticipated affective and productive outcomes. The impact of level of diversity, faultlines and individual differences in diversity attitudes on anticipated outcomes were

  16. The problems of high-nitrogen steels production

    International Nuclear Information System (INIS)

    Svyazhin, A.G.; Kaputkina, L.M.; Efimenko, S.P.

    1999-01-01

    Analysis of existing technologies of high-nitrogen steel production shows that rational nitrogen content in mass production corresponds to moderate high values. Such steels can be smelted under normal or slightly elevated pressure in steelmaking units, using processes of mass- and special metallurgy. High-nitrogen steels with ''overequilibrium'' nitrogen content are promising, but technology and equipment for production of them are complicated, and production of such steels is therefore limited. (orig.)

  17. High-resolution mitochondrial DNA analysis sheds light on human diversity, cultural interactions, and population mobility in Northwestern Amazonia.

    Science.gov (United States)

    Arias, Leonardo; Barbieri, Chiara; Barreto, Guillermo; Stoneking, Mark; Pakendorf, Brigitte

    2018-02-01

    Northwestern Amazonia (NWA) is a center of high linguistic and cultural diversity. Several language families and linguistic isolates occur in this region, as well as different subsistence patterns, with some groups being foragers and others agriculturalists. In addition, speakers of Eastern Tukanoan languages are known for practicing linguistic exogamy, a marriage system in which partners are taken from different language groups. In this study, we use high-resolution mitochondrial DNA sequencing to investigate the impact of this linguistic and cultural diversity on the genetic relationships and population structure of NWA groups. We collected saliva samples from individuals representing 40 different NWA ethnolinguistic groups and sequenced 439 complete mitochondrial genomes to an average coverage of 1,030×. The mtDNA data revealed that NWA populations have high genetic diversity with extensive sharing of haplotypes among groups. Moreover, groups who practice linguistic exogamy have higher genetic diversity, while the foraging Nukak have lower genetic diversity. We also find that rivers play a more important role than either geography or language affiliation in structuring the genetic relationships of populations. Contrary to the view of NWA as a pristine area inhabited by small human populations living in isolation, our data support a view of high diversity and contact among different ethnolinguistic groups, with movement along rivers probably facilitating this contact. Additionally, we provide evidence for the impact of cultural practices, such as linguistic exogamy, on patterns of genetic variation. Overall, this study provides new data and insights into a remote and little-studied region of the world. © 2017 Wiley Periodicals, Inc.

  18. A High Diversity in Chitinolytic and Chitosanolytic Species and Enzymes and Their Oligomeric Products Exist in Soil with a History of Chitin and Chitosan Exposure.

    Science.gov (United States)

    Nampally, Malathi; Rajulu, M B Govinda; Gillet, Dominique; Suryanarayanan, T S; Moerschbacher, Bruno B

    2015-01-01

    Chitin is one of the most abundant biomolecules on earth, and its partially de-N-acetylated counterpart, chitosan, is one of the most promising biotechnological resources due to its diversity in structure and function. Recently, chitin and chitosan modifying enzymes (CCMEs) have gained increasing interest as tools to engineer chitosans with specific functions and reliable performance in biotechnological and biomedical applications. In a search for novel CCME, we isolated chitinolytic and chitosanolytic microorganisms from soils with more than ten-years history of chitin and chitosan exposure and screened them for chitinase and chitosanase isoenzymes as well as for their patterns of oligomeric products by incubating their secretomes with chitosan polymers. Of the 60 bacterial strains isolated, only eight were chitinolytic and/or chitosanolytic, while 20 out of 25 fungal isolates were chitinolytic and/or chitosanolytic. The bacterial isolates produced rather similar patterns of chitinolytic and chitosanolytic enzymes, while the fungal isolates produced a much broader range of different isoenzymes. Furthermore, diverse mixtures of oligosaccharides were formed when chitosan polymers were incubated with the secretomes of select fungal species. Our study indicates that soils with a history of chitin and chitosan exposure are a good source of novel CCME for chitosan bioengineering.

  19. A High Diversity in Chitinolytic and Chitosanolytic Species and Enzymes and Their Oligomeric Products Exist in Soil with a History of Chitin and Chitosan Exposure

    Science.gov (United States)

    Nampally, Malathi; Rajulu, M. B. Govinda; Gillet, Dominique; Suryanarayanan, T. S.; Moerschbacher, Bruno B.

    2015-01-01

    Chitin is one of the most abundant biomolecules on earth, and its partially de-N-acetylated counterpart, chitosan, is one of the most promising biotechnological resources due to its diversity in structure and function. Recently, chitin and chitosan modifying enzymes (CCMEs) have gained increasing interest as tools to engineer chitosans with specific functions and reliable performance in biotechnological and biomedical applications. In a search for novel CCME, we isolated chitinolytic and chitosanolytic microorganisms from soils with more than ten-years history of chitin and chitosan exposure and screened them for chitinase and chitosanase isoenzymes as well as for their patterns of oligomeric products by incubating their secretomes with chitosan polymers. Of the 60 bacterial strains isolated, only eight were chitinolytic and/or chitosanolytic, while 20 out of 25 fungal isolates were chitinolytic and/or chitosanolytic. The bacterial isolates produced rather similar patterns of chitinolytic and chitosanolytic enzymes, while the fungal isolates produced a much broader range of different isoenzymes. Furthermore, diverse mixtures of oligosaccharides were formed when chitosan polymers were incubated with the secretomes of select fungal species. Our study indicates that soils with a history of chitin and chitosan exposure are a good source of novel CCME for chitosan bioengineering. PMID:26273652

  20. High-Resolution Biogeochemical Simulation Identifies Practical Opportunities for Bioenergy Landscape Intensification Across Diverse US Agricultural Regions

    Science.gov (United States)

    Field, J.; Adler, P. R.; Evans, S.; Paustian, K.; Marx, E.; Easter, M.

    2015-12-01

    The sustainability of biofuel expansion is strongly dependent on the environmental footprint of feedstock production, including both direct impacts within feedstock-producing areas and potential leakage effects due to disruption of existing food, feed, or fiber production. Assessing and minimizing these impacts requires novel methods compared to traditional supply chain lifecycle assessment. When properly validated and applied at appropriate spatial resolutions, biogeochemical process models are useful for simulating how the productivity and soil greenhouse gas fluxes of cultivating both conventional crops and advanced feedstock crops respond across gradients of land quality and management intensity. In this work we use the DayCent model to assess the biogeochemical impacts of agricultural residue collection, establishment of perennial grasses on marginal cropland or conservation easements, and intensification of existing cropping at high spatial resolution across several real-world case study landscapes in diverse US agricultural regions. We integrate the resulting estimates of productivity, soil carbon changes, and nitrous oxide emissions with crop production budgets and lifecycle inventories, and perform a basic optimization to generate landscape cost/GHG frontiers and determine the most practical opportunities for low-impact feedstock provisioning. The optimization is constrained to assess the minimum combined impacts of residue collection, land use change, and intensification of existing agriculture necessary for the landscape to supply a commercial-scale biorefinery while maintaining exiting food, feed, and fiber production levels. These techniques can be used to assess how different feedstock provisioning strategies perform on both economic and environmental criteria, and sensitivity of performance to environmental and land use factors. The included figure shows an example feedstock cost-GHG mitigation tradeoff frontier for a commercial-scale cellulosic

  1. Exploring fungal diversity in deep-sea sediments from Okinawa Trough using high-throughput Illumina sequencing

    Science.gov (United States)

    Zhang, Xiao-Yong; Wang, Guang-Hua; Xu, Xin-Ya; Nong, Xu-Hua; Wang, Jie; Amin, Muhammad; Qi, Shu-Hua

    2016-10-01

    The present study investigated the fungal diversity in four different deep-sea sediments from Okinawa Trough using high-throughput Illumina sequencing of the nuclear ribosomal internal transcribed spacer-1 (ITS1). A total of 40,297 fungal ITS1 sequences clustered into 420 operational taxonomic units (OTUs) with 97% sequence similarity and 170 taxa were recovered from these sediments. Most ITS1 sequences (78%) belonged to the phylum Ascomycota, followed by Basidiomycota (17.3%), Zygomycota (1.5%) and Chytridiomycota (0.8%), and a small proportion (2.4%) belonged to unassigned fungal phyla. Compared with previous studies on fungal diversity of sediments from deep-sea environments by culture-dependent approach and clone library analysis, the present result suggested that Illumina sequencing had been dramatically accelerating the discovery of fungal community of deep-sea sediments. Furthermore, our results revealed that Sordariomycetes was the most diverse and abundant fungal class in this study, challenging the traditional view that the diversity of Sordariomycetes phylotypes was low in the deep-sea environments. In addition, more than 12 taxa accounted for 21.5% sequences were found to be rarely reported as deep-sea fungi, suggesting the deep-sea sediments from Okinawa Trough harbored a plethora of different fungal communities compared with other deep-sea environments. To our knowledge, this study is the first exploration of the fungal diversity in deep-sea sediments from Okinawa Trough using high-throughput Illumina sequencing.

  2. High bacterial diversity in epilithic biofilms of oligotrophic mountain lakes.

    Science.gov (United States)

    Bartrons, Mireia; Catalan, Jordi; Casamayor, Emilio O

    2012-11-01

    Benthic microbial biofilms attached to rocks (epilithic) are major sites of carbon cycling and can dominate ecosystem primary production in oligotrophic lakes. We studied the bacterial community composition of littoral epilithic biofilms in five connected oligotrophic high mountain lakes located at different altitudes by genetic fingerprinting and clone libraries of the 16S rRNA gene. Different intra-lake samples were analyzed, and consistent changes in community structure (chlorophyll a and organic matter contents, and bacterial community composition) were observed along the altitudinal gradient, particularly related with the location of the lake above or below the treeline. Epilithic biofilm genetic fingerprints were both more diverse among lakes than within lakes and significantly different between montane (below the tree line) and alpine lakes (above the tree line). The genetic richness in the epilithic biofilm was much higher than in the plankton of the same lacustrine area studied in previous works, with significantly idiosyncratic phylogenetic composition (specifically distinct from lake plankton or mountain soils). Data suggest the coexistence of aerobic, anaerobic, phototrophic, and chemotrophic microorganisms in the biofilm, Bacteroidetes and Cyanobacteria being the most important bacterial taxa, followed by Alpha-, Beta-, Gamma-, and Deltaproteobacteria, Chlorobi, Planctomycetes, and Verrucomicrobia. The degree of novelty was especially high for epilithic Bacteroidetes, and up to 50 % of the sequences formed monophyletic clusters distantly related to any previously reported sequence. More than 35 % of the total sequences matched at <95 % identity to any previously reported 16S rRNA gene, indicating that alpine epilithic biofilms are unexplored habitats that contain a substantial degree of novelty within a short geographical distance. Further research is needed to determine whether these communities are involved in more biogeochemical pathways than

  3. Contextualising diversity in TV drama: Policies, practices and discourses

    Directory of Open Access Journals (Sweden)

    Alexander Dhoest

    2015-12-01

    Full Text Available This paper discusses the representation of social minority groups in Flemish TV drama. After a brief review of academic literature on the topic, three questions are asked. First, 'How should diversity be represented?', discussing broadcasting policies on diversity as well as the opinions of minority groups. Second, 'How is diversity actually represented?' Beside quantitative data, this analysis includes a qualitative assessment of six recent TV drama productions on Flemish television. Third, 'Why is diversity represented this way' Here, production practices and discourses are analysed, using in-depth interviews with production staff in order to better understand their reasons and motivations. The findings show that diversity is addressed by public broadcasting policies, but that minority groups are unhappy about their portrayal. Indeed, quantitative research shows that they are generally under-represented, while qualitative research discloses a lack of diversity in these portrayals. Based on the interviews with producers, these representational patterns can be connected to a number of practical and dramatic considerations, which however do not excuse the lack of on screen diversity.

  4. Dose-on-demand production of diverse 18F-radiotracers for preclinical applications using a continuous flow microfluidic system.

    Science.gov (United States)

    Matesic, Lidia; Kallinen, Annukka; Greguric, Ivan; Pascali, Giancarlo

    2017-09-01

    The production of 18 F-radiotracers using continuous flow microfluidics is under-utilized due to perceived equipment limitations. We describe the dose-on-demand principle, whereby the back-to-back production of multiple, diverse 18 F-radiotracers can be prepared on the same day, on the same microfluidic system using the same batch of [ 18 F]fluoride, the same microreactor, the same HPLC column and SPE cartridge to obtain a useful production yield. [ 18 F]MEL050, [ 18 F]Fallypride and [ 18 F]PBR111 were radiolabeled with [ 18 F]fluoride using the Advion NanoTek Microfluidic Synthesis System. The outlet of the microreactor was connected to an automated HPLC injector and following the collection of the product, SPE reformulation produced the 18 F-radiotracer in productions for [ 18 F]MEL050 and [ 18 F]Fallypride were performed at total flow rates of 20μL/min, resulting in 40±13% and 25±13% RCY respectively. [ 18 F]PBR111 was performed at 200μL/min to obtain 27±8% RCY. Molar activities for each 18 F-radiotracer were >100GBq/μmol and radiochemical purities were >97%, implying that the cleaning procedure was effective. Using the same initial solution of [ 18 F]fluoride, microreactor, HPLC column and SPE cartridge, three diverse 18 F-radiotracers could be produced in yields sufficient for preclinical studies in a back-to-back fashion using a microfluidic system with no detectable cross-contamination. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  5. Effects of plant diversity on primary production and species interactions in brackish water angiosperm communities

    DEFF Research Database (Denmark)

    Salo, Tiina; Gustafsson, Camilla; Boström, Christoffer

    2009-01-01

    Research on plant biodiversity and ecosystem functioning has mainly focused on terrestrial ecosystems, and our understanding of how plant species diversity and interactions affect processes in marine ecosystems is still limited. To investigate if plant species richness and composition influence...... plant productivity in brackish water angiosperm communities, a 14 wk field experiment was conducted. Using a replacement design with a standardized initial aboveground biomass, shoots of Zostera marina, Potamogeton filiformis and P. perfoliatus were planted on a shallow, sandy bottom in replicated...

  6. Diversity and Structure of Diazotrophic Communities in Mangrove Rhizosphere, Revealed by High-Throughput Sequencing.

    Science.gov (United States)

    Zhang, Yanying; Yang, Qingsong; Ling, Juan; Van Nostrand, Joy D; Shi, Zhou; Zhou, Jizhong; Dong, Junde

    2017-01-01

    Diazotrophic communities make an essential contribution to the productivity through providing new nitrogen. However, knowledge of the roles that both mangrove tree species and geochemical parameters play in shaping mangove rhizosphere diazotrophic communities is still elusive. Here, a comprehensive examination of the diversity and structure of microbial communities in the rhizospheres of three mangrove species, Rhizophora apiculata , Avicennia marina , and Ceriops tagal , was undertaken using high - throughput sequencing of the 16S rRNA and nifH genes. Our results revealed a great diversity of both the total microbial composition and the diazotrophic composition specifically in the mangrove rhizosphere. Deltaproteobacteria and Gammaproteobacteria were both ubiquitous and dominant, comprising an average of 45.87 and 86.66% of total microbial and diazotrophic communities, respectively. Sulfate-reducing bacteria belonging to the Desulfobacteraceae and Desulfovibrionaceae were the dominant diazotrophs. Community statistical analyses suggested that both mangrove tree species and additional environmental variables played important roles in shaping total microbial and potential diazotroph communities in mangrove rhizospheres. In contrast to the total microbial community investigated by analysis of 16S rRNA gene sequences, most of the dominant diazotrophic groups identified by nifH gene sequences were significantly different among mangrove species. The dominant diazotrophs of the family Desulfobacteraceae were positively correlated with total phosphorus, but negatively correlated with the nitrogen to phosphorus ratio. The Pseudomonadaceae were positively correlated with the concentration of available potassium, suggesting that diazotrophs potentially play an important role in biogeochemical cycles, such as those of nitrogen, phosphorus, sulfur, and potassium, in the mangrove ecosystem.

  7. Diversity and Structure of Diazotrophic Communities in Mangrove Rhizosphere, Revealed by High-Throughput Sequencing

    Directory of Open Access Journals (Sweden)

    Yanying Zhang

    2017-10-01

    Full Text Available Diazotrophic communities make an essential contribution to the productivity through providing new nitrogen. However, knowledge of the roles that both mangrove tree species and geochemical parameters play in shaping mangove rhizosphere diazotrophic communities is still elusive. Here, a comprehensive examination of the diversity and structure of microbial communities in the rhizospheres of three mangrove species, Rhizophora apiculata, Avicennia marina, and Ceriops tagal, was undertaken using high-throughput sequencing of the 16S rRNA and nifH genes. Our results revealed a great diversity of both the total microbial composition and the diazotrophic composition specifically in the mangrove rhizosphere. Deltaproteobacteria and Gammaproteobacteria were both ubiquitous and dominant, comprising an average of 45.87 and 86.66% of total microbial and diazotrophic communities, respectively. Sulfate-reducing bacteria belonging to the Desulfobacteraceae and Desulfovibrionaceae were the dominant diazotrophs. Community statistical analyses suggested that both mangrove tree species and additional environmental variables played important roles in shaping total microbial and potential diazotroph communities in mangrove rhizospheres. In contrast to the total microbial community investigated by analysis of 16S rRNA gene sequences, most of the dominant diazotrophic groups identified by nifH gene sequences were significantly different among mangrove species. The dominant diazotrophs of the family Desulfobacteraceae were positively correlated with total phosphorus, but negatively correlated with the nitrogen to phosphorus ratio. The Pseudomonadaceae were positively correlated with the concentration of available potassium, suggesting that diazotrophs potentially play an important role in biogeochemical cycles, such as those of nitrogen, phosphorus, sulfur, and potassium, in the mangrove ecosystem.

  8. Eimeria species occurrence varies between geographic regions and poultry production systems and may influence parasite genetic diversity.

    Science.gov (United States)

    Chengat Prakashbabu, B; Thenmozhi, V; Limon, G; Kundu, K; Kumar, S; Garg, R; Clark, E L; Srinivasa Rao, A S R; Raj, D G; Raman, M; Banerjee, P S; Tomley, F M; Guitian, J; Blake, D P

    2017-01-15

    Coccidiosis is one of the biggest challenges faced by the global poultry industry. Recent studies have highlighted the ubiquitous distribution of all Eimeria species which can cause this disease in chickens, but intriguingly revealed a regional divide in genetic diversity and population structure for at least one species, Eimeria tenella. The drivers associated with such distinct geographic variation are unclear, but may impact on the occurrence and extent of resistance to anticoccidial drugs and future subunit vaccines. India is one of the largest poultry producers in the world and includes a transition between E. tenella populations defined by high and low genetic diversity. The aim of this study was to identify risk factors associated with the prevalence of Eimeria species defined by high and low pathogenicity in northern and southern states of India, and seek to understand factors which vary between the regions as possible drivers for differential genetic variation. Faecal samples and data relating to farm characteristics and management were collected from 107 farms from northern India and 133 farms from southern India. Faecal samples were analysed using microscopy and PCR to identify Eimeria occurrence. Multiple correspondence analysis was applied to transform correlated putative risk factors into a smaller number of synthetic uncorrelated factors. Hierarchical cluster analysis was used to identify poultry farm typologies, revealing three distinct clusters in the studied regions. The association between clusters and presence of Eimeria species was assessed by logistic regression. The study found that large-scale broiler farms in the north were at greatest risk of harbouring any Eimeria species and a larger proportion of such farms were positive for E. necatrix, the most pathogenic species. Comparison revealed a more even distribution for E. tenella across production systems in south India, but with a lower overall occurrence. Such a polarised region- and

  9. Bacterial Glycosyltransferases: Challenges and opportunities of a highly diverse enzyme class toward tailoring natural products

    Directory of Open Access Journals (Sweden)

    Jochen eSchmid

    2016-02-01

    Full Text Available The enzyme subclass of glycosyltransferases (EC 2.4 currently comprises 97 families as specified by CAZy classification. One of their important roles is in the biosynthesis of disaccharides, oligosaccharides and polysaccharides by catalyzing the transfer of sugar moieties from activated donor molecules to other sugar molecules. In addition glycosyltransferases also catalyze the transfer of sugar moieties onto aglycons, which is of great relevance for the synthesis of many high value natural products. Bacterial glycosyltransferases show a higher sequence similarity in comparison to mammalian ones. Even when most glycosyltransferases are poorly explored, state of the art technologies, such as protein engineering, domain swapping or computational analysis strongly enhance our understanding and utilization of these very promising classes of proteins. This perspective article will focus on bacterial glycosyltransferases, especially on classification, screening and engineering strategies to alter substrate specificity. The future development in these fields as well as obstacles and challenges will be highlighted and discussed.

  10. Classroom Management Strategies of Highly Effective Teachers in Diverse Middle Schools: Be Strict and Calm, Not Mean

    Science.gov (United States)

    McGregor, Katheryne L.

    2012-01-01

    This qualitative research study investigated and identified the classroom management strategies of 12 highly effective middle school teachers who served diverse student populations at two different school sites. In addition, this research explored the beliefs and experiences of 305 diverse middle school students regarding their experiences with…

  11. Diversity and social cohesion : the case of Jane-Finch, a highly diverse lower-income Toronto neighbourhood

    NARCIS (Netherlands)

    Ahmadi, D.

    2017-01-01

    Diversity has increasingly emerged as the core focus of many studies concerning factors impacting on social cohesion. Various scholars have concluded that diversity is detrimental to cohesion. Most of this research, however, draws generalisations based upon quantitative data and fails to account

  12. Individuals and the variation needed for high species diversity in forest trees

    Science.gov (United States)

    James S. Clark

    2010-01-01

    In the past, explanations for high species diversity have been sought at the species level. Theory shows that coexistence requires substantial differences between species, but species-level data rarely provide evidence for such differences. Using data from forests in the southeastern United States, I show here that variation evident at the individual level provides for...

  13. Diversity and Complexity in the Classroom: Valuing Racial and Cultural Diversity

    Science.gov (United States)

    du Plessis, Pierre; Bisschoff, Tom

    2007-01-01

    From a diversity perspective, all students should receive an education that continuously affirms human diversity--one that embraces the history and culture of all racial groups and that teaches people of colour to take change of their own destinies. With regards to teaching, a diversity perspective assumes that teachers will hold high expectations…

  14. Microbiological Spoilage of High-Sugar Products

    Science.gov (United States)

    Thompson, Sterling

    The high-sugar products discussed in this chapter are referred to as chocolate, sugar confectionery (non-chocolate), liquid sugars, sugar syrups, and honey. Products grouped in the sugar confectionery category include hard candy, soft/gummy candy, caramel, toffee, licorice, marzipan, creams, jellies, and nougats. A common intrinsic parameter associated with high-sugar products is their low water activity (a w), which is known to inhibit the growth of most spoilage and pathogenic bacteria. However, spoilage can occur as a result of the growth of osmophilic yeasts and xerophilic molds (Von Richter, 1912; Anand & Brown, 1968; Brown, 1976). The a w range for high-sugar products is between 0.20 and 0.80 (Banwart, 1979; Richardson, 1987; Lenovich & Konkel, 1992; ICMSF, 1998; Jay, Loessner, & Golden, 2005). Spoilage of products, such as chocolate-covered cherries, results from the presence of yeasts in the liquid sugar brine or the cherry. Generally, the spoiled product will develop leakers. The chocolate covering the cherry would not likely be a source of yeast contamination.

  15. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity.

    Science.gov (United States)

    Hertzog, Lionel R; Meyer, Sebastian T; Weisser, Wolfgang W; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas

  16. Experimental Manipulation of Grassland Plant Diversity Induces Complex Shifts in Aboveground Arthropod Diversity

    Science.gov (United States)

    Hertzog, Lionel R.; Meyer, Sebastian T.; Weisser, Wolfgang W.; Ebeling, Anne

    2016-01-01

    Changes in producer diversity cause multiple changes in consumer communities through various mechanisms. However, past analyses investigating the relationship between plant diversity and arthropod consumers focused only on few aspects of arthropod diversity, e.g. species richness and abundance. Yet, shifts in understudied facets of arthropod diversity like relative abundances or species dominance may have strong effects on arthropod-mediated ecosystem functions. Here we analyze the relationship between plant species richness and arthropod diversity using four complementary diversity indices, namely: abundance, species richness, evenness (equitability of the abundance distribution) and dominance (relative abundance of the dominant species). Along an experimental gradient of plant species richness (1, 2, 4, 8, 16 and 60 plant species), we sampled herbivorous and carnivorous arthropods using pitfall traps and suction sampling during a whole vegetation period. We tested whether plant species richness affects consumer diversity directly (i), or indirectly through increased productivity (ii). Further, we tested the impact of plant community composition on arthropod diversity by testing for the effects of plant functional groups (iii). Abundance and species richness of both herbivores and carnivores increased with increasing plant species richness, but the underlying mechanisms differed between the two trophic groups. While higher species richness in herbivores was caused by an increase in resource diversity, carnivore richness was driven by plant productivity. Evenness of herbivore communities did not change along the gradient in plant species richness, whereas evenness of carnivores declined. The abundance of dominant herbivore species showed no response to changes in plant species richness, but the dominant carnivores were more abundant in species-rich plant communities. The functional composition of plant communities had small impacts on herbivore communities, whereas

  17. Differential iridoid production as revealed by a diversity panel of 84 cultivated and wild blueberry species.

    Directory of Open Access Journals (Sweden)

    Courtney P Leisner

    Full Text Available Cultivated blueberry (Vaccinium corymbosum, Vaccinium angustifolium, Vaccinium darrowii, and Vaccinium virgatum is an economically important fruit crop native to North America and a member of the Ericaceae family. Several species in the Ericaceae family including cranberry, lignonberry, bilberry, and neotropical blueberry species have been shown to produce iridoids, a class of pharmacologically important compounds present in over 15 plant families demonstrated to have a wide range of biological activities in humans including anti-cancer, anti-bacterial, and anti-inflammatory. While the antioxidant capacity of cultivated blueberry has been well studied, surveys of iridoid production in blueberry have been restricted to fruit of a very limited number of accessions of V. corymbosum, V. angustifolium and V. virgatum; none of these analyses have detected iridoids. To provide a broader survey of iridoid biosynthesis in cultivated blueberry, we constructed a panel of 84 accessions representing a wide range of cultivated market classes, as well as wild blueberry species, and surveyed these for the presence of iridoids. We identified the iridoid glycoside monotropein in fruits and leaves of all 13 wild Vaccinium species, yet only five of the 71 cultivars. Monotropein positive cultivars all had recent introgressions from wild species, suggesting that iridoid production can be targeted through breeding efforts that incorporate wild germplasm. A series of diverse developmental tissues was also surveyed in the diversity panel, demonstrating a wide range in iridoid content across tissues. Taken together, this data provides the foundation to dissect the molecular and genetic basis of iridoid production in blueberry.

  18. Differential iridoid production as revealed by a diversity panel of 84 cultivated and wild blueberry species.

    Science.gov (United States)

    Leisner, Courtney P; Kamileen, Mohamed O; Conway, Megan E; O'Connor, Sarah E; Buell, C Robin

    2017-01-01

    Cultivated blueberry (Vaccinium corymbosum, Vaccinium angustifolium, Vaccinium darrowii, and Vaccinium virgatum) is an economically important fruit crop native to North America and a member of the Ericaceae family. Several species in the Ericaceae family including cranberry, lignonberry, bilberry, and neotropical blueberry species have been shown to produce iridoids, a class of pharmacologically important compounds present in over 15 plant families demonstrated to have a wide range of biological activities in humans including anti-cancer, anti-bacterial, and anti-inflammatory. While the antioxidant capacity of cultivated blueberry has been well studied, surveys of iridoid production in blueberry have been restricted to fruit of a very limited number of accessions of V. corymbosum, V. angustifolium and V. virgatum; none of these analyses have detected iridoids. To provide a broader survey of iridoid biosynthesis in cultivated blueberry, we constructed a panel of 84 accessions representing a wide range of cultivated market classes, as well as wild blueberry species, and surveyed these for the presence of iridoids. We identified the iridoid glycoside monotropein in fruits and leaves of all 13 wild Vaccinium species, yet only five of the 71 cultivars. Monotropein positive cultivars all had recent introgressions from wild species, suggesting that iridoid production can be targeted through breeding efforts that incorporate wild germplasm. A series of diverse developmental tissues was also surveyed in the diversity panel, demonstrating a wide range in iridoid content across tissues. Taken together, this data provides the foundation to dissect the molecular and genetic basis of iridoid production in blueberry.

  19. iPad Deployment in a Diverse Urban High School: A Formative Experiment

    Science.gov (United States)

    Frey, Nancy; Fisher, Douglas; Lapp, Diane

    2015-01-01

    We explore the use of iPads in a diverse urban high school and the ways in which teachers and students were supported to integrate these tools into their instruction. We provided 4 English teachers with 20 iPads with little or no professional development about how to integrate them into their instruction. Using a formative experiment design, we…

  20. Ethnic diversity and knowledge synergies: Rethinking the interrelations

    DEFF Research Database (Denmark)

    Lauring, Jakob

    2005-01-01

    desire to see ethnical diversity as productive. Theoretical reviews and empirical research have indicated that the link between diversity and knowledge synergy cannot be taken for granted. This article argues that some theoretical rethinking of managerial strategies toward cultural diversity...

  1. A collective phase in resource competition in a highly diverse ecosystem

    Science.gov (United States)

    Tikhonov, Mikhail; Monasson, Remi

    Recent technological advances uncovered that most habitats, including the human body, harbor hundreds of coexisting microbial ``species''. The problem of understanding such complex communities is currently at the forefront of medical and environmental sciences. A particularly intriguing question is whether the high-diversity regime (large number of species N) gives rise to qualitatively novel phenomena that could not be intuited from analysis of low-dimensional models (with few species). However, few existing approaches allow studying this regime, except in simulations. Here, we use methods of statistical physics to show that the large- N limit of a classic ecological model of resource competition introduced by MacArthur in 1969 can be solved analytically. Our results provide a tractable model where the implications of large dimensionality of eco-evolutionary problems can be investigated. In particular, we show that at high diversity, the MacArthur model exhibits a phase transition into a curious regime where the environment constructed by the community becomes a collective property, insensitive to the external conditions such as the total resource influx supplied to the community. Supported by Harvard Center of Mathematical Sciences and Applications, and the Simons Foundation. This work was completed at the Aspen Center for Physics, supported by National Science Foundation Grant PHY-1066293.

  2. Production Quality Control Of Microfluidic Chip Designs

    DEFF Research Database (Denmark)

    Calaon, Matteo; Hansen, Hans Nørgaard; Tosello, Guido

    2012-01-01

    The challenge of fabricating geometries with critical dimensions ranging from few microns down to 10 nanometers with high production rate is delaying the development of nanotechnology based products. Diverse research works have shown the capability of technologies such as UV lithography, nano imp...

  3. Life Cycle Assessment of a Highly Diverse Vegetable Multi-Cropping System in Fengqiu County, China

    Directory of Open Access Journals (Sweden)

    Li Li

    2018-03-01

    Full Text Available Agricultural biodiversity usually leads to greater sustainability in production practices. To understand the environmental implications of the development of village-level multi-cropping in rural China, we compared the environmental impact of a highly diverse vegetable multi-cropping system to a conventional wheat/maize rotation system based on the method of life cycle assessment (LCA. Using household level cultivation data, this study examined the gate-to-gate environmental impacts of on-site cultivation practices relating to the production of 10,000 nutrient equivalent units. Results show that vegetable multi-cropping resulted in decreased average land requirement, and diesel, water and electricity usage by 69.8%, 62.2%, 71.7%, and 63.4%, respectively, while average nitrogen (Total N, phosphorus (P2O5, and potassium (K2O usage in vegetable multi-cropping systems decreased by 16.3%, 42.1%, and 75.8%, respectively. Additional corresponding effects led to a decrease in the total global warming, eutrophication, and acidification potentials from external inputs by 21.6%, 16.7%, and 16.2% of the entire system, respectively. Moreover, the midpoint human toxicity potential from pesticide usage of the vegetable multi-cropping system was lower than that of the conventional system. However, the midpoint eco-toxicity potential from pesticide usage was higher due to certain highly toxic substances, and both human and eco-toxicity potentials from heavy metals were all higher by a few orders of magnitudes. Thus, to mitigate these detrimental consequences, some related measures are proposed for sustainable practices in the future implementation of multi-cropping systems.

  4. Regional Diversity and Diversification in Mammals.

    Science.gov (United States)

    Machac, Antonin; Graham, Catherine H

    2017-01-01

    The effects of regional diversity on diversification remain controversial. The classic hypothesis that diversification decelerates as regional diversity increases has been recently revived. Yet, there is little geographic evidence for slower diversification across regions of high diversity, and diversity is often thought to promote diversification through its effects on ecological divergence and speciation. Here, we use the newest phylogeny for mammals (4,990 species) and two different methods to test the effects of regional diversity on diversification. We find that regions of high diversity are dominated by expanding clades that are far from their estimated carrying capacities. Regions of low diversity host clades that are small and mostly saturated. These results were supported across mammals and their six largest orders. They were corroborated by the two methods when controlling for clade relatedness, clade nestedness, and clade size. Together, these results reject the hypothesis that high geographic concentration of mammals effectively suppresses their further diversification. Instead, highly diverse regions (especially the tropics) seem to act as the engine of mammalian richness.

  5. Culture-dependent and independent studies of microbial diversity in highly copper-contaminated Chilean marine sediments.

    Science.gov (United States)

    Besaury, Ludovic; Marty, Florence; Buquet, Sylvaine; Mesnage, Valérie; Muyzer, Gerard; Quillet, Laurent

    2013-02-01

    Cultivation and molecular-based approaches were used to study microbial diversity in two Chilean marine sediments contaminated with high (835 ppm) and very high concentrations of copper (1,533 ppm). The diversity of cultivable bacteria resistant to copper was studied at oxic and anoxic conditions, focusing on sulfate-, thiosulfate-, and iron-reducing bacteria. For both sediments, the cultivable bacteria isolated at oxic conditions were mostly affiliated to the genus Bacillus, while at anoxic conditions the majority of the cultivable bacteria found were closely related to members of the genera Desulfovibrio, Sphingomonas, and Virgibacillus. Copper resistance was between 100 and 400 ppm, with the exception of a strain affiliated to members of the genus Desulfuromonas, which was resistant up to 1,000 ppm of copper. In parallel, cloning and sequencing of 16S rRNA was performed to study the total bacterial diversity in the sediments. A weak correlation was observed between the isolated strains and the 16S rRNA operational taxonomic units detected. The presence of copper resistance genes (copA, cusA, and pcoA) was tested for all the strains isolated; only copA was detected in a few isolates, suggesting that other copper resistance mechanisms could be used by the bacteria in those highly copper-contaminated sediments.

  6. High-throughput screening platform for natural product-based drug discovery against 3 neglected tropical diseases: human African trypanosomiasis, leishmaniasis, and Chagas disease.

    Science.gov (United States)

    Annang, F; Pérez-Moreno, G; García-Hernández, R; Cordon-Obras, C; Martín, J; Tormo, J R; Rodríguez, L; de Pedro, N; Gómez-Pérez, V; Valente, M; Reyes, F; Genilloud, O; Vicente, F; Castanys, S; Ruiz-Pérez, L M; Navarro, M; Gamarro, F; González-Pacanowska, D

    2015-01-01

    African trypanosomiasis, leishmaniasis, and Chagas disease are 3 neglected tropical diseases for which current therapeutic interventions are inadequate or toxic. There is an urgent need to find new lead compounds against these diseases. Most drug discovery strategies rely on high-throughput screening (HTS) of synthetic chemical libraries using phenotypic and target-based approaches. Combinatorial chemistry libraries contain hundreds of thousands of compounds; however, they lack the structural diversity required to find entirely novel chemotypes. Natural products, in contrast, are a highly underexplored pool of unique chemical diversity that can serve as excellent templates for the synthesis of novel, biologically active molecules. We report here a validated HTS platform for the screening of microbial extracts against the 3 diseases. We have used this platform in a pilot project to screen a subset (5976) of microbial extracts from the MEDINA Natural Products library. Tandem liquid chromatography-mass spectrometry showed that 48 extracts contain potentially new compounds that are currently undergoing de-replication for future isolation and characterization. Known active components included actinomycin D, bafilomycin B1, chromomycin A3, echinomycin, hygrolidin, and nonactins, among others. The report here is, to our knowledge, the first HTS of microbial natural product extracts against the above-mentioned kinetoplastid parasites. © 2014 Society for Laboratory Automation and Screening.

  7. Overcoming the Gap between Diversity Recruitment Research and Practice

    Science.gov (United States)

    Bocanegra, Joel O.

    2012-01-01

    The profession of school psychology has repeatedly advocated for increasing the diversity of its membership. However, the production of diversity recruitment research has not coalesced with the urgency espoused by organizations governing school psychology. This gap between official organizational position and production of literature has…

  8. Diversity and Phenology of Wild Bees in a Highly Disturbed Tropical Dry Forest "Desierto de la Tatacoa", Huila-Colombia.

    Science.gov (United States)

    Poveda-Coronel, C A; Riaño-Jiménez, D; Cure, J R

    2018-01-12

    Colombian tropical dry forest is considered the most endangered tropical biome due to anthropic activities. Desierto de la Tatacoa (DsT) is an example of high disturbed tropical dry forest which still maintains a high biodiversity. The objective of the study was to record the diversity and phenology of wild bees in this place by monthly sampling between December 2014 and December 2016 in a 9-km 2 area. During the study, there was a prolonged El Niño-Southern Oscillation period. Bees were collected by entomological nets, malaise traps, eugenol scent trapping, and nest traps. Shannon index was calculated to estimate diversity and Simpson index to determine dominance of a species. The effect of environmental conditions (wet and dry season) in richness and abundance was analyzed by paired T tests. A total of 3004 bee specimens were collected, belonging to 80 species from Apidae, Megachilidae, Halictidae, and Colletidae. Apidae was the most diverse. Shannon index value was 2.973 (discarding Apis mellifera Linnaeus 1758 data); thus, DsT can be considered as a zone of high wild bee diversity. Dry and rainy season showed differences in diversity (p < 0.05). Rainy season showed larger blooming periods and higher bee diversity than dry season. In both seasons, social species were dominant (e.g., A. mellifera or Trigona fulviventris Guérin 1844). Although DsT is a highly disturbed ecosystem, this study found it has the second highest number of genera and the fourth highest number of species reported in Colombia.

  9. Diverse microbial species survive high ammonia concentrations

    Science.gov (United States)

    Kelly, Laura C.; Cockell, Charles S.; Summers, Stephen

    2012-04-01

    Planetary protection regulations are in place to control the contamination of planets and moons with terrestrial micro-organisms in order to avoid jeopardizing future scientific investigations relating to the search for life. One environmental chemical factor of relevance in extraterrestrial environments, specifically in the moons of the outer solar system, is ammonia (NH3). Ammonia is known to be highly toxic to micro-organisms and may disrupt proton motive force, interfere with cellular redox reactions or cause an increase of cell pH. To test the survival potential of terrestrial micro-organisms exposed to such cold, ammonia-rich environments, and to judge whether current planetary protection regulations are sufficient, soil samples were exposed to concentrations of NH3 from 5 to 35% (v/v) at -80°C and room temperature for periods up to 11 months. Following exposure to 35% NH3, diverse spore-forming taxa survived, including representatives of the Firmicutes (Bacillus, Sporosarcina, Viridibacillus, Paenibacillus, Staphylococcus and Brevibacillus) and Actinobacteria (Streptomyces). Non-spore forming organisms also survived, including Proteobacteria (Pseudomonas) and Actinobacteria (Arthrobacter) that are known to have environmentally resistant resting states. Clostridium spp. were isolated from the exposed soil under anaerobic culture. High NH3 was shown to cause a reduction in viability of spores over time, but spore morphology was not visibly altered. In addition to its implications for planetary protection, these data show that a large number of bacteria, potentially including spore-forming pathogens, but also environmentally resistant non-spore-formers, can survive high ammonia concentrations.

  10. Household food production is positively associated with dietary diversity and intake of nutrient-dense foods for older preschool children in poorer families: Results from a nationally-representative survey in Nepal.

    Science.gov (United States)

    Mulmi, Prajula; Masters, William A; Ghosh, Shibani; Namirembe, Grace; Rajbhandary, Ruchita; Manohar, Swetha; Shrestha, Binod; West, Keith P; Webb, Patrick

    2017-01-01

    Nutrition-sensitive interventions supporting enhanced household food production have potential to improve child dietary quality. However, heterogeneity in market access may cause systematic differences in program effectiveness depending on household wealth and child age. Identifying these effect modifiers can help development agencies specify and target their interventions. This study investigates mediating effects of household wealth and child age on links between farm production and child diets, as measured by production and intake of nutrient-dense food groups. Two rounds (2013 and 2014) of nationally representative survey data (n = 5,978 observations) were used to measure production and children's dietary intake, as well as a household wealth index and control variables, including breastfeeding. Novel steps used include measuring production diversity in terms of both species grown and food groups grown, as well as testing for mediating effects of family wealth and age of child. We find significant associations between child dietary diversity and agricultural diversity in terms of diversity of food groups and of species grown, especially for older children in poorer households, and particularly for fruits and vegetables, dairy and eggs. With each additional food group produced, log-odds of meeting minimum dietary diversity score (≥4) increase by 0.25 (p = 0.01) for children aged 24-59 months. For younger children aged 18-23 months there is a similar effect size but only in the poorest two quintiles of household wealth, and for infants 6-18 months we find no correlation between production and intake in most models. Child dietary intake is associated with the composition of farm production, most evident among older preschool children and in poorer households. To improve the nutrition of infants, other interventions are needed; and for relatively wealthier households, own farm production may displace market purchases, which could attenuate the impact of household

  11. Household food production is positively associated with dietary diversity and intake of nutrient-dense foods for older preschool children in poorer families: Results from a nationally-representative survey in Nepal.

    Directory of Open Access Journals (Sweden)

    Prajula Mulmi

    Full Text Available Nutrition-sensitive interventions supporting enhanced household food production have potential to improve child dietary quality. However, heterogeneity in market access may cause systematic differences in program effectiveness depending on household wealth and child age. Identifying these effect modifiers can help development agencies specify and target their interventions.This study investigates mediating effects of household wealth and child age on links between farm production and child diets, as measured by production and intake of nutrient-dense food groups.Two rounds (2013 and 2014 of nationally representative survey data (n = 5,978 observations were used to measure production and children's dietary intake, as well as a household wealth index and control variables, including breastfeeding. Novel steps used include measuring production diversity in terms of both species grown and food groups grown, as well as testing for mediating effects of family wealth and age of child.We find significant associations between child dietary diversity and agricultural diversity in terms of diversity of food groups and of species grown, especially for older children in poorer households, and particularly for fruits and vegetables, dairy and eggs. With each additional food group produced, log-odds of meeting minimum dietary diversity score (≥4 increase by 0.25 (p = 0.01 for children aged 24-59 months. For younger children aged 18-23 months there is a similar effect size but only in the poorest two quintiles of household wealth, and for infants 6-18 months we find no correlation between production and intake in most models.Child dietary intake is associated with the composition of farm production, most evident among older preschool children and in poorer households. To improve the nutrition of infants, other interventions are needed; and for relatively wealthier households, own farm production may displace market purchases, which could attenuate the impact

  12. Characterization of glutathione peroxidase diversity in the symbiotic sea anemone Anemonia viridis.

    Science.gov (United States)

    Pey, Alexis; Zamoum, Thamilla; Christen, Richard; Merle, Pierre-Laurent; Furla, Paola

    2017-01-01

    Cnidarians living in symbiosis with photosynthetic dinoflagellates (commonly named zooxanthellae) are exposed to high concentrations of reactive oxygen species (ROS) upon illumination. To quench ROS production, both the cnidarian host and zooxanthellae express a full suite of antioxidant enzymes. Studying antioxidative balance is therefore crucial to understanding how symbiotic cnidarians cope with ROS production. We characterized glutathione peroxidases (GPx) in the symbiotic cnidarian Anemonia viridis by analysis of their isoform diversity, their activity distribution in the three cellular compartments (ectoderm, endoderm and zooxanthellae) and their involvement in the response to thermal stress. We identified a GPx repertoire through a phylogenetic analysis showing 7 GPx transcripts belonging to the A. viridis host and 4 GPx transcripts strongly related to Symbiodinium sp. The biochemical approach, used for the first time with a cnidarian species, allowed the identification of GPx activity in the three cellular compartments and in the animal mitochondrial fraction, and revealed a high GPx electrophoretic diversity. The symbiotic lifestyle of zooxanthellae requires more GPx activity and diversity than that of free-living species. Heat stress induced no modification of GPx activities. We highlight a high GPx diversity in A. viridis tissues by genomic and biochemical approaches. GPx activities represent an overall constitutive enzymatic pattern inherent to symbiotic lifestyle adaptation. This work allows the characterization of the GPx family in a symbiotic cnidarian and establishes a foundation for future studies of GPx in symbiotic cnidarians. Copyright © 2016 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  13. Curcumin profiing and genetic diversity of different accessions of Curcuma longa L.

    Directory of Open Access Journals (Sweden)

    Neelam Arya

    2016-01-01

    Full Text Available Objective: To investigate the genetic diversity and variation in active compound of turmeric rhizomes collected from different niches of Uttarakhand. Methods: Genetic diversity and relationship of Curcuma longa accessions was evaluated by random amplification polymorphism DNA analysis and curcumin profiling was evaluated by high performance liquid chromatography method. Results: The curcumin contents in 20 accessions of turmeric rhizomes were found to be in the range of 0.90% to 3.26%. All accessions were separated into six groups (92% genetic similarity by using 10 decamer oligonucleotide primers for the amplification of genomic DNA. Conclusions: The results indicated the possibility of selecting high quality clones for large scale production.

  14. Mitochondrial DNA Analyses Indicate High Diversity, Expansive Population Growth and High Genetic Connectivity of Vent Copepods (Dirivultidae) across Different Oceans.

    Science.gov (United States)

    Gollner, Sabine; Stuckas, Heiko; Kihara, Terue C; Laurent, Stefan; Kodami, Sahar; Martinez Arbizu, Pedro

    2016-01-01

    Communities in spatially fragmented deep-sea hydrothermal vents rich in polymetallic sulfides could soon face major disturbance events due to deep-sea mineral mining, such that unraveling patterns of gene flow between hydrothermal vent populations will be an important step in the development of conservation policies. Indeed, the time required by deep-sea populations to recover following habitat perturbations depends both on the direction of gene flow and the number of migrants available for re-colonization after disturbance. In this study we compare nine dirivultid copepod species across various geological settings. We analyze partial nucleotide sequences of the mtCOI gene and use divergence estimates (FST) and haplotype networks to infer intraspecific population connectivity between vent sites. Furthermore, we evaluate contrasting scenarios of demographic population expansion/decline versus constant population size (using, for example, Tajima's D). Our results indicate high diversity, population expansion and high connectivity of all copepod populations in all oceans. For example, haplotype diversity values range from 0.89 to 1 and FST values range from 0.001 to 0.11 for Stygiopontius species from the Central Indian Ridge, Mid Atlantic Ridge, East Pacific Rise, and Eastern Lau Spreading Center. We suggest that great abundance and high site occupancy by these species favor high genetic diversity. Two scenarios both showed similarly high connectivity: fast spreading centers with little distance between vent fields and slow spreading centers with greater distance between fields. This unexpected result may be due to some distinct frequency of natural disturbance events, or to aspects of individual life histories that affect realized rates of dispersal. However, our statistical performance analyses showed that at least 100 genomic regions should be sequenced to ensure accurate estimates of migration rate. Our demography parameters demonstrate that dirivultid

  15. High diversity at PRDM9 in chimpanzees and bonobos.

    Directory of Open Access Journals (Sweden)

    Linn Fenna Groeneveld

    Full Text Available BACKGROUND: The PRDM9 locus in mammals has increasingly attracted research attention due to its role in mediating chromosomal recombination and possible involvement in hybrid sterility and hence speciation processes. The aim of this study was to characterize sequence variation at the PRDM9 locus in a sample of our closest living relatives, the chimpanzees and bonobos. METHODOLOGY/PRINCIPAL FINDINGS: PRDM9 contains a highly variable and repetitive zinc finger array. We amplified this domain using long-range PCR and determined the DNA sequences using conventional Sanger sequencing. From 17 chimpanzees representing three subspecies and five bonobos we obtained a total of 12 alleles differing at the nucleotide level. Based on a data set consisting of our data and recently published Pan PRDM9 sequences, we found that at the subspecies level, diversity levels did not differ among chimpanzee subspecies or between chimpanzee subspecies and bonobos. In contrast, the sample of chimpanzees harbors significantly more diversity at PRDM9 than samples of humans. Pan PRDM9 shows signs of rapid evolution including no alleles or ZnFs in common with humans as well as signals of positive selection in the residues responsible for DNA binding. CONCLUSIONS AND SIGNIFICANCE: The high number of alleles specific to the genus Pan, signs of positive selection in the DNA binding residues, and reported lack of conservation of recombination hotspots between chimpanzees and humans suggest that PRDM9 could be active in hotspot recruitment in the genus Pan. Chimpanzees and bonobos are considered separate species and do not have overlapping ranges in the wild, making the presence of shared alleles at the amino acid level between the chimpanzee and bonobo species interesting in view of the hypothesis that PRDM9 plays a universal role in interspecific hybrid sterility.

  16. Lactic acid bacteria involved in cocoa beans fermentation from Ivory Coast: Species diversity and citrate lyase production.

    Science.gov (United States)

    Ouattara, Hadja D; Ouattara, Honoré G; Droux, Michel; Reverchon, Sylvie; Nasser, William; Niamke, Sébastien L

    2017-09-01

    Microbial fermentation is an indispensable process for high quality chocolate from cocoa bean raw material. lactic acid bacteria (LAB) are among the major microorganisms responsible for cocoa fermentation but their exact role remains to be elucidated. In this study, we analyzed the diversity of LAB in six cocoa producing regions of Ivory Coast. Ribosomal 16S gene sequence analysis showed that Lactobacillus plantarum and Leuconostoc mesenteroides are the dominant LAB species in these six regions. In addition, other species were identified as the minor microbial population, namely Lactobacillus curieae, Enterococcus faecium, Fructobacillus pseudoficulneus, Lactobacillus casei, Weissella paramesenteroides and Weissella cibaria. However, in each region, the LAB microbial population was composed of a restricted number of species (maximum 5 species), which varied between the different regions. LAB implication in the breakdown of citric acid was investigated as a fundamental property for a successful cocoa fermentation process. High citrate lyase producer strains were characterized by rapid citric acid consumption, as revealed by a 4-fold decrease in citric acid concentration in the growth medium within 12h, concomitant with an increase in acetic acid and lactic acid concentration. The production of citrate lyase was strongly dependent on environmental conditions, with optimum production at acidic pH (pHfermentation. This study reveals that one of the major roles of LAB in the cocoa fermentation process involves the breakdown of citric acid during the early stage of cocoa fermentation through the activity of citrate lyase. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Hydrothermal activity, functional diversity and chemoautotrophy are major drivers of seafloor carbon cycling

    NARCIS (Netherlands)

    Bell, J.B.; Woulds, C.; van Oevelen, D.

    2017-01-01

    Hydrothermal vents are highly dynamic ecosystems and are unusually energy rich in the deep-sea. Insitu hydrothermal-based productivity combined with sinking photosynthetic organic matter in a softsedimentsetting creates geochemically diverse environments, which remain poorly studied. Here,we use

  18. High-end encroachment patterns of new products

    NARCIS (Netherlands)

    Rhee, van der B.; Schmidt, G.; Orden, van J.

    2012-01-01

    Previous research describes two key ways in which a new product may encroach on an existing market. In high-end encroachment, the new product first sells to high-end customers and then diffuses down-market; in low-end encroachment, the new product enters at the low end and encroaches up-market. This

  19. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium.

    Science.gov (United States)

    Machado, Henrique; Gram, Lone

    2017-01-01

    Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationships using several analyses (16S rRNA, MLSA, fur , amino-acid usage, ANI), which allowed us to identify two misidentified strains. Genome analyses also revealed occurrence of higher and lower GC content clades, correlating with phylogenetic clusters. Pan- and core-genome analysis revealed the conservation of 25% of the genome throughout the genus, with a large and open pan-genome. The major source of genomic diversity could be traced to the smaller chromosome and plasmids. Several of the physiological traits studied in the genus did not correlate with phylogenetic data. Since horizontal gene transfer (HGT) is often suggested as a source of genetic diversity and a potential driver of genomic evolution in bacterial species, we looked into evidence of such in Photobacterium genomes. Genomic islands were the source of genomic differences between strains of the same species. Also, we found transposase genes and CRISPR arrays that suggest multiple encounters with foreign DNA. Presence of genomic exchange traits was widespread and abundant in the genus, suggesting a role in genomic evolution. The high genetic variability and indications of genetic exchange make it difficult to elucidate genome evolutionary paths and raise the awareness of the roles of foreign DNA in the genomic evolution of environmental organisms.

  20. Production of highly unsaturated fatty acids using agro-processing by-products

    CSIR Research Space (South Africa)

    Jacobs, A

    2008-11-01

    Full Text Available The South African agro-processing industry generates millions of tons of cereal derived by-products annually. The by-products from biofuel production are expected to increase these volumes dramatically. Highly unsaturated fatty acids (HUFA...

  1. High genetic diversity and low population structure in Porter's sunflower (Helianthus porteri).

    Science.gov (United States)

    Gevaert, Scott D; Mandel, Jennifer R; Burke, John M; Donovan, Lisa A

    2013-01-01

    Granite outcrops in the southeastern United States are rare and isolated habitats that support edaphically controlled communities dominated by herbaceous plants. They harbor rare and endemic species that are expected to have low genetic variability and high population structure due to small population sizes and their disjunct habitat. We test this expectation for an annual outcrop endemic, Helianthus porteri (Porter's sunflower). Contrary to expectation, H. porteri has relatively high genetic diversity (H e = 0.681) and relatively low genetic structure among the native populations (F ST = 0.077) when compared to 5 other Helianthus species (N = 288; 18 expressed sequence tag-SSR markers). These findings suggest greater gene flow than expected. The potential for gene flow is supported by the analysis of transplant populations established with propagules from a common source in 1959. One population established close to a native population (1.5 km) at the edge of the natural range is genetically similar to and shares rare alleles with the adjacent native population and is distinct from the central source population. In contrast, a transplant population established north of the native range has remained similar to the source population. The relatively high genetic diversity and low population structure of this species, combined with the long-term success of transplanted populations, bode well for its persistence as long as the habitat persists.

  2. Prokaryotic diversity and biochemical properties in aging artificial pit mud used for the production of Chinese strong flavor liquor.

    Science.gov (United States)

    Sun, Zhongke; Chen, Can; Hou, Xiaoge; Zhang, Jie; Tian, Fengshou; Li, Chengwei

    2017-10-01

    At present, artificial pit mud (APM) is widely used in Chinese liquor-making industry and plays a particular role in the production of Chinese strong flavor liquor (CSFL). However, APM frequently ages during fermentation, thus becoming unsuitable for sustainable use due to its low-quality. The reasons behind, and results of, APM aging during the production of CSFL are not yet understood. Sequencing the V4 region of the 16S rRNA gene shows that prokaryotic diversity is significantly decreased (Shannon's diversity index, P  aging APM. On the phylum level, the increase of Firmicutes and decrease of Proteobacteria are the main consequences of APM aging during the production of CSFL. The counting of cultivatable bacteria confirmed that there was a large increase in Lactobacilli and aerobic spore-forming bacteria in aging low-quality APM (more than twofold). Unexpectedly, the total number of caproic acid-producing bacteria, mainly Clostridia , did not change significantly between the two kinds of APM. Furthermore, biochemical analysis indicates that the pH and the levels of NH 4 + and K + are decreased in aging low-quality APM ( P  aging can be controlled potentially by adjustment of environmental factors and/or supplementation of diminished or missed microorganisms.

  3. Diversity spurs diversification in ecological communities

    Science.gov (United States)

    Calcagno, Vincent; Jarne, Philippe; Loreau, Michel; Mouquet, Nicolas; David, Patrice

    2017-06-01

    Diversity is a fundamental, yet threatened, property of ecological systems. The idea that diversity can itself favour diversification, in an autocatalytic process, is very appealing but remains controversial. Here, we study a generalized model of ecological communities and investigate how the level of initial diversity influences the possibility of evolutionary diversification. We show that even simple models of intra- and inter-specific ecological interactions can predict a positive effect of diversity on diversification: adaptive radiations may require a threshold number of species before kicking-off. We call this phenomenon DDAR (diversity-dependent adaptive radiations) and identify mathematically two distinct pathways connecting diversity to diversification, involving character displacement and the positive diversity-productivity relationship. Our results may explain observed delays in adaptive radiations at the macroscale and diversification patterns reported in experimental microbial communities, and shed new light on the dynamics of ecological diversity, the diversity-dependence of diversification rates, and the consequences of biodiversity loss.

  4. Diversity spurs diversification in ecological communities.

    Science.gov (United States)

    Calcagno, Vincent; Jarne, Philippe; Loreau, Michel; Mouquet, Nicolas; David, Patrice

    2017-06-09

    Diversity is a fundamental, yet threatened, property of ecological systems. The idea that diversity can itself favour diversification, in an autocatalytic process, is very appealing but remains controversial. Here, we study a generalized model of ecological communities and investigate how the level of initial diversity influences the possibility of evolutionary diversification. We show that even simple models of intra- and inter-specific ecological interactions can predict a positive effect of diversity on diversification: adaptive radiations may require a threshold number of species before kicking-off. We call this phenomenon DDAR (diversity-dependent adaptive radiations) and identify mathematically two distinct pathways connecting diversity to diversification, involving character displacement and the positive diversity-productivity relationship. Our results may explain observed delays in adaptive radiations at the macroscale and diversification patterns reported in experimental microbial communities, and shed new light on the dynamics of ecological diversity, the diversity-dependence of diversification rates, and the consequences of biodiversity loss.

  5. Long-term followup of bilateral high (Sober) urinary diversion in patients with posterior urethral valves and its effect on bladder function

    NARCIS (Netherlands)

    Ghanem, MA; Nijman, RJM

    Purpose: Although valve ablation is the treatment of choice in patients with posterior urethral valves (PLTV), temporary high (ureterostomy) diversion remains controversial. In this study we evaluated the effect of bilateral Sober high urinary diversion on renal and bladder function. Materials and

  6. The Catalytic Diversity of Multimodular Polyketide Synthases: Natural Product Biosynthesis Beyond Textbook Assembly Rules.

    Science.gov (United States)

    Gulder, Tobias A M; Freeman, Michael F; Piel, Jörn

    2011-03-01

    Bacterial multimodular polyketide synthases (PKSs) are responsible for the biosynthesis of a wide range of pharmacologically active natural products. These megaenzymes contain numerous catalytic and structural domains and act as biochemical templates to generate complex polyketides in an assembly line-like fashion. While the prototypical PKS is composed of only a few different domain types that are fused together in a combinatorial fashion, an increasing number of enzymes is being found that contain additional components. These domains can introduce remarkably diverse modifications into polyketides. This review discusses our current understanding of such noncanonical domains and their role in expanding the biosynthetic versatility of bacterial PKSs.

  7. Consistent patterns of high alpha and low beta diversity in tropical parasitic and free-living protists.

    Science.gov (United States)

    Lentendu, Guillaume; Mahé, Frédéric; Bass, David; Rueckert, Sonja; Stoeck, Thorsten; Dunthorn, Micah

    2018-05-30

    Tropical animals and plants are known to have high alpha diversity within forests, but low beta diversity between forests. By contrast, it is unknown whether microbes inhabiting the same ecosystems exhibit similar biogeographic patterns. To evaluate the biogeographies of tropical protists, we used metabarcoding data of species sampled in the soils of three lowland Neotropical rainforests. Taxa-area and distance-decay relationships for three of the dominant protist taxa and their subtaxa were estimated at both the OTU and phylogenetic levels, with presence-absence and abundance-based measures. These estimates were compared to null models. High local alpha and low regional beta diversity patterns were consistently found for both the parasitic Apicomplexa and the largely free-living Cercozoa and Ciliophora. Similar to animals and plants, the protists showed spatial structures between forests at the OTU and phylogenetic levels, and only at the phylogenetic level within forests. These results suggest that the biogeographies of macro- and micro-organismal eukaryotes in lowland Neotropical rainforests are partially structured by the same general processes. However, and unlike the animals and plants, the protist OTUs did not exhibit spatial structures within forests, which hinders our ability to estimate the local and regional diversity of protists in tropical forests. © 2018 John Wiley & Sons Ltd.

  8. Microbial Diversity-Based Novel Crop Protection Products

    Energy Technology Data Exchange (ETDEWEB)

    Pioneer Hi-Bred International Inc.; DuPont Experimental Station; Yalpani, Ronald Flannagan, Rafael Herrmann, James Presnail, Tamas Torok, and Nasser; Herrmann, Rafael; Presnail, James; Torok, Tamas; Yalpani, Nasser

    2007-05-10

    Extremophilic microorganisms are adapted to survive in ecological niches with high temperatures, extremes of pH, high salt concentrations, high pressure, radiation, etc. Extremophiles produce unique biocatalysts and natural products that function under extreme conditions comparab le to those prevailing in various industrial processes. Therefore, there is burgeoning interest in bioprospecting for extremophiles with potential immediate use in agriculture, the food, chemical, and pharm aceutical industries, and environmental biotechnology. Over the years, several thousand extremophilic bacteria, archaea, and filamentous fungi were collected at extreme environmental sites in the USA, the Chernobyl Exclusion Zone surrounding the faeild nuclear power plant in Ukraine, in and around Lake Baikal in Siberia, and at geothermal sites on the Kamchatka peninsula in Russia. These organisms were cultured under proprietary conditions, and the cell- free supernatants were screened for biological activities against plant pathogenic fungi and major crop damaging insects. Promising peptide lead molecules were isolated, characterized, and sequenced. Relatively high hit rates characterized the tested fermentation broths. Of the 26,000 samples screened, over thousand contained biological activity of interest. A fair number of microorganisms expressed broad- spectrum antifungal or insecticidal activity. Two- dozen broadly antifungal peptides (AFPs) are alr eady patent protected, and many more tens are under further investigation. Tapping the gene pool of extremophilic microorganisms to provide novel ways of crop protection proved a successful strategy.

  9. Microbial Diversity-Based Novel Crop Protection Products

    International Nuclear Information System (INIS)

    Flannagan, Ronald; Herrmann, Rafael; Presnail, James; Torok, Tamas; Yalpani, Nasser

    2007-01-01

    Extremophilic microorganisms are adapted to survive in ecological niches with high temperatures, extremes of pH, high salt concentrations, high pressure, radiation, etc. Extremophiles produce unique biocatalysts and natural products that function under extreme conditions comparab le to those prevailing in various industrial processes. Therefore, there is burgeoning interest in bioprospecting for extremophiles with potential immediate use in agriculture, the food, chemical, and pharm aceutical industries, and environmental biotechnology. Over the years, several thousand extremophilic bacteria, archaea, and filamentous fungi were collected at extreme environmental sites in the USA, the Chernobyl Exclusion Zone surrounding the faeild nuclear power plant in Ukraine, in and around Lake Baikal in Siberia, and at geothermal sites on the Kamchatka peninsula in Russia. These organisms were cultured under proprietary conditions, and the cell- free supernatants were screened for biological activities against plant pathogenic fungi and major crop damaging insects. Promising peptide lead molecules were isolated, characterized, and sequenced. Relatively high hit rates characterized the tested fermentation broths. Of the 26,000 samples screened, over thousand contained biological activity of interest. A fair number of microorganisms expressed broad- spectrum antifungal or insecticidal activity. Two- dozen broadly antifungal peptides (AFPs) are alr eady patent protected, and many more tens are under further investigation. Tapping the gene pool of extremophilic microorganisms to provide novel ways of crop protection proved a successful strategy.

  10. Cultural diversity in the digital age: EU competences, policies and regulations for diverse audio-visual and online content

    NARCIS (Netherlands)

    Irion, K.; Valcke, P.; Psychogiopoulou, E.

    2015-01-01

    Cultural diversity is a multifaceted concept that differs from the notion of media pluralism. However, the two concepts share important concerns particularly as regards content production, content distribution and access to content. This chapter considers the EU’s role in contributing to diverse

  11. Application of the Nutrition Functional Diversity indicator to assess food system contributions to dietary diversity and sustainable diets of Malawian households.

    Science.gov (United States)

    Luckett, Brian G; DeClerck, Fabrice A J; Fanzo, Jessica; Mundorf, Adrienne R; Rose, Donald

    2015-09-01

    Dietary diversity is associated with nutrient adequacy and positive health outcomes but indicators to measure diversity have focused primarily on consumption, rather than sustainable provisioning of food. The Nutritional Functional Diversity score was developed by ecologists to describe the contribution of biodiversity to sustainable diets. We have employed this tool to estimate the relative contribution of home production and market purchases in providing nutritional diversity to agricultural households in Malawi and examine how food system provisioning varies by time, space and socio-economic conditions. A secondary analysis of nationally representative household consumption data to test the applicability of the Nutritional Functional Diversity score. The data were collected between 2010 and 2011 across the country of Malawi. Households (n 11 814) from predominantly rural areas of Malawi. Nutritional Functional Diversity varied demographically, geographically and temporally. Nationally, purchased foods contributed more to household nutritional diversity than home produced foods (mean score=17·5 and 7·8, respectively). Households further from roads and population centres had lower overall diversity (PFunctional Diversity score is an effective indicator for identifying populations with low nutritional diversity and the relative roles that markets, agricultural extension and home production play in achieving nutritional diversity. This information may be used by policy makers to plan agricultural and market-based interventions that support sustainable diets and local food systems.

  12. Global status of and prospects for protection of terrestrial geophysical diversity.

    Science.gov (United States)

    Sanderson, Eric W; Segan, Daniel B; Watson, James E M

    2015-06-01

    Conservation of representative facets of geophysical diversity may help conserve biological diversity as the climate changes. We conducted a global classification of terrestrial geophysical diversity and analyzed how land protection varies across geophysical diversity types. Geophysical diversity was classified in terms of soil type, elevation, and biogeographic realm and then compared to the global distribution of protected areas in 2012. We found that 300 (45%) of 672 broad geophysical diversity types currently meet the Convention on Biological Diversity's Aichi Target 11 of 17% terrestrial areal protection, which suggested that efforts to implement geophysical diversity conservation have a substantive basis on which to build. However, current protected areas were heavily biased toward high elevation and low fertility soils. We assessed 3 scenarios of protected area expansion and found that protection focused on threatened species, if fully implemented, would also protect an additional 29% of geophysical diversity types, ecoregional-focused protection would protect an additional 24%, and a combined scenario would protect an additional 42%. Future efforts need to specifically target low-elevation sites with productive soils for protection and manage for connectivity among geophysical diversity types. These efforts may be hampered by the sheer number of geophysical diversity facets that the world contains, which makes clear target setting and prioritization an important next step. © 2015 Society for Conservation Biology.

  13. Genetic and phenotypic diversity of naturally isolated wild strains of Aspergillus niger with hyper glucose oxidase production

    Directory of Open Access Journals (Sweden)

    MAHMOUD EL-HARIRI

    2015-12-01

    Full Text Available Glucose oxidase (GOx is the basic stone for many of biological industry worldwide. The improvement of GOx production basically depends on selection of hyper producer strain of Aspergillus niger. Selective isolation and screening for natural hyper producer strains of A. niger and sequence analysis of the GOD gene, which is responsible for production of the enzyme, are very effective approaches to investigate the naturally modified strains of A. niger with hyper productive capacity of GOx enzyme. The aims of the current study were selective isolation of naturally hyper GOx producing strains of A. niger and evaluation of their GOx activities under optimized parameters in the laboratory. Five wild Egyptian isolates of A. niger were screened for GOx and catalase activity using two types of modified basal liquid media. The GOx activity was evaluated by high throughout liquid phase system. The isolates showed a variable activity for GOx production ranged from 0 to 28.7 U.ml-1. One isolate coded Strain 7 was negative GOx producer on Vogel's broth medium in comparison to other isolates, while its GOx activity on Cazpek Dox was considered as positive (7.28 U.ml-1. It was concluded that GOx production is affected by three controllable factors – the basal media components, time of incubation, and the strain with its adaption to the media components‎. Also, the catalase activity was tested and it was produced with a different degree of variability, which may be reflected on GOx stability. GOD genes of these wild variant of A. niger were cloned and sequenced to determine intraspecies diversity of GOD between the wild variants. The comparison of isolated wild variants to other reference hyper GOx producer strains of A. niger was performed to determine if the GOD sequence analysis of these strains can be distinguished based on their GOx activity. This is the first report for isolation and detection of naturally A. niger hyper GOx-producer strains with

  14. Diversity in research projects - A key to success?

    Science.gov (United States)

    Henkel, Daniela; Eisenhauer, Anton; Taubner, Isabelle

    2017-04-01

    According to demographers, psychologists, sociologists and economists diverse groups, which are groups of different race, ethnicity, gender and sexual orientation, are more innovative than homogeneous groups. This is also true for groups working together in research collaborations and international cooperation involving a culturally and functionally diverse mix of individuals who have to be integrated into an effective unit - a project team. If the goal is scientific excellence, diversity should be an essential ingredient to conduct science on high level productivity, quality and innovation. Effective teamwork is a key to project success and prime responsibilities of the project manager. Therefore, the project manager has to take into consideration different characteristics such as cultures, languages, and different values related to individual project partners. Here we show how diversity can affect the performance of a research project. Furthermore, the presentation indicates skills and abilities which are required for the management in order to deal also with the challenges of diversity in research projects. The presentation is based on insights experienced in the context of an Innovative Training Network (ITN) project within Marie Skłodowska-Curie Actions of the European HORIZON 2020 program and TRION a Collaborative Research Project in the Framework of the Trilateral Program of the German Research Foundation.

  15. Estimation of Anadara tuberculosa genetic diversity in five mangroves from Tumaco, using Cytochrome oxidase I enzyme

    Directory of Open Access Journals (Sweden)

    Esmeralda Chamorro L

    2016-09-01

    Full Text Available Objective. To estimate the genetic diversity of the Anadara tuberculosa en five mangrove swams of Tumaco, Nariño, Colombia using as a mitocondrial molecular marker the cytochromo oxidase sub-unit I (COI. Materials and methods. A total of 50 individuals were collected from the San Jorge, La Tiburonera, El Pajal, La Playa y Bajito Vaquería mangrove swamps, randomly selecting 10 specimens of each zone. The tissue sample was worked with absolute alcohol at ambient temperature in microtubes. DNA was extracted, and the mitocondrial DNA was amplified using the PCR technique (polymerase chain reaction. The amplified and quantified products of PCR were sequenced on both sides (Macrogen. Each one of the obtained sequences was edited and aligned. Later, the parameters of genetic diversity (haplotypical and nucleotidical were measured, and the analysis of distribution between frequency pairs (Mistmach distribution was elaborated. Finally, the analysis of nucleotidic variation and population structure (AMOVA was completed. Results. The amplified product gene weighed 710 bp. The haplotypical diversity reported for all the populations was high (0.683±0.060 and the reported nucleotídical diversity was low for all the populations (0.040±0.020. The AMOVA results indicate that the variance amongst populations is low (4.20% and that the variance within populations is high (95.80%. Conclusions. The studied populations are not structured and although there is a decrease of natural banks, the genetic diversity is high.

  16. Smallholder pig production

    DEFF Research Database (Denmark)

    Braae, Uffe Christian; Ngowi, Helena; Johansen, Maria Vang

    2013-01-01

    A cross-sectional study was carried out in the Mbeya Region, Tanzania, with the aim of describing the distribution and diversity of ectoparasites on pigs, within confinement and free-range production systems of smallholder farms. A total of 128 farms were surveyed, with 96 practising confinement...... and 32 practising free-range production systems. The prevalence of ectoparasites on pigs within confinement and free-range production systems was 24% and 84%, respectively. Logistic regression analyses revealed that keeping pigs in a free-range system and the presence of neighbouring pigs were risk...... although highly prevalent within both production systems. Keeping pigs in a free-range system and contact with neighbouring pigs were main risk factors for the presence of ectoparasites. Confinement was highly effective as a preventive tool against hard ticks....

  17. Multiple criteria decision-making process to derive consensus desired genetic gains for a dairy cattle breeding objective for diverse production systems

    NARCIS (Netherlands)

    Kariuki, C.M.; Arendonk, van J.A.M.; Kahi, A.K.; Komen, H.

    2017-01-01

    Dairy cattle industries contribute to food and nutrition security and are a source of income for numerous households in many developing countries. Selective breeding can enhance efficiency in these industries. Developing dairy industries are characterized by diverse production and marketing

  18. Species Diversity Enhances Predator Growth Rates

    International Nuclear Information System (INIS)

    Olson, M.H.; Jacobs, R.P.; O'Donnell, E.B.

    2007-01-01

    Predators can be important top-down regulators of community structure and are known to have both positive and negative effects on species diversity. However, little is known about the reciprocal effects of species diversity on predators. Across a set of 80 lakes in Connecticut, USA, we found a strong positive correlation between prey species diversity (using the Shannon-Weiner Diversity Index) and growth rates of largemouth bass (Micropterus salmoides). This correlation was strongest for small predators and decreased with body size. Although the underlying mechanisms are not known, the correlation is not driven by total fish abundance, predator abundance, or productivity.

  19. High Schools, Race, and America's Future: What Students Can Teach Us about Morality, Diversity, and Community

    Science.gov (United States)

    Blum, Lawrence

    2012-01-01

    In "High Schools, Race, and America's Future", Lawrence Blum offers a lively account of a rigorous high school course on race and racism. Set in a racially, ethnically, and economically diverse high school, the book chronicles students' engagement with one another, with a rich and challenging academic curriculum, and with questions that relate…

  20. Unexpected high diversity of galling insects in the Amazonian upper canopy: the savanna out there.

    Science.gov (United States)

    Julião, Genimar R; Venticinque, Eduardo M; Fernandes, G Wilson; Price, Peter W

    2014-01-01

    A relatively large number of studies reassert the strong relationship between galling insect diversity and extreme hydric and thermal status in some habitats, and an overall pattern of a greater number of galling species in the understory of scleromorphic vegetation. We compared galling insect diversity in the forest canopy and its relationship with tree richness among upland terra firme, várzea, and igapó floodplains in Amazonia, Brazil. The soils of these forest types have highly different hydric and nutritional status. Overall, we examined the upper layer of 1,091 tree crowns. Galling species richness and abundance were higher in terra firme forests compared to várzea and igapó forests. GLM-ANCOVA models revealed that the number of tree species sampled in each forest type was determinant in the gall-forming insect diversity. The ratio between galling insect richness and number of tree species sampled (GIR/TSS ratio) was higher in the terra firme forest and in seasonally flooded igapó, while the várzea presented the lowest GIR/TSS ratio. In this study, we recorded unprecedented values of galling species diversity and abundance per sampling point. The GIR/TSS ratio from várzea was approximately 2.5 times higher than the highest value of this ratio ever reported in the literature. Based on this fact, we ascertained that várzea and igapó floodplain forests (with lower GIA and GIR), together with the speciose terra firme galling community emerge as the gall diversity apex landscape among all biogeographic regions already investigated. Contrary to expectation, our results also support the "harsh environment hypothesis", and unveil the Amazonian upper canopy as similar to Mediterranean vegetation habitats, hygrothermically stressed environments with leaf temperature at lethal limits and high levels of leaf sclerophylly.

  1. Unexpected high diversity of galling insects in the Amazonian upper canopy: the savanna out there.

    Directory of Open Access Journals (Sweden)

    Genimar R Julião

    Full Text Available A relatively large number of studies reassert the strong relationship between galling insect diversity and extreme hydric and thermal status in some habitats, and an overall pattern of a greater number of galling species in the understory of scleromorphic vegetation. We compared galling insect diversity in the forest canopy and its relationship with tree richness among upland terra firme, várzea, and igapó floodplains in Amazonia, Brazil. The soils of these forest types have highly different hydric and nutritional status. Overall, we examined the upper layer of 1,091 tree crowns. Galling species richness and abundance were higher in terra firme forests compared to várzea and igapó forests. GLM-ANCOVA models revealed that the number of tree species sampled in each forest type was determinant in the gall-forming insect diversity. The ratio between galling insect richness and number of tree species sampled (GIR/TSS ratio was higher in the terra firme forest and in seasonally flooded igapó, while the várzea presented the lowest GIR/TSS ratio. In this study, we recorded unprecedented values of galling species diversity and abundance per sampling point. The GIR/TSS ratio from várzea was approximately 2.5 times higher than the highest value of this ratio ever reported in the literature. Based on this fact, we ascertained that várzea and igapó floodplain forests (with lower GIA and GIR, together with the speciose terra firme galling community emerge as the gall diversity apex landscape among all biogeographic regions already investigated. Contrary to expectation, our results also support the "harsh environment hypothesis", and unveil the Amazonian upper canopy as similar to Mediterranean vegetation habitats, hygrothermically stressed environments with leaf temperature at lethal limits and high levels of leaf sclerophylly.

  2. Importance of riparian remnants for frog species diversity in a highly fragmented rainforest.

    Science.gov (United States)

    Rodríguez-Mendoza, Clara; Pineda, Eduardo

    2010-12-23

    Tropical forests undergo continuous transformation to other land uses, resulting in landscapes typified by forest fragments surrounded by anthropogenic habitats. Small forest fragments, specifically strip-shaped remnants flanking streams (referred to as riparian remnants), can be particularly important for the maintenance and conservation of biodiversity within highly fragmented forests. We compared frog species diversity between riparian remnants, other forest fragments and cattle pastures in a tropical landscape in Los Tuxtlas, Mexico. We found similar species richness in the three habitats studied and a similar assemblage structure between riparian remnants and forest fragments, although species composition differed by 50 per cent. Frog abundance was halved in riparian remnants compared with forest fragments, but was twice that found in pastures. Our results suggest that riparian remnants play an important role in maintaining a portion of frog species diversity in a highly fragmented forest, particularly during environmentally stressful (hot and dry) periods. In this regard, however, the role of riparian remnants is complementary, rather than substitutive, with respect to the function of other forest fragments within the fragmented forest.

  3. Impact of highly saline wetland ecosystem on floral diversity of the Cholistan desert

    International Nuclear Information System (INIS)

    Gill, A.H.; Ahmad, K.S.; Habib, S.; Ahmad, S.A.; Nawaz, T.; Ahmad, F.

    2012-01-01

    The impact of highly saline wetland ecosystem created under Salinity Control and Reclamation Project (SCARP) on floral diversity was investigated in the arid environments of Cholistan Desert. Species richness, diversity indices and evenness indices were worked out to look at the distance at which the salt water has altered the native vegetation. Four sites including SCARP ponds of different ages (S1, S2, S3 and S4), and a reference site (SR) were selected for vegetation studies and data were recorded by 1 x 1 m quadrats, which were laid on permanent transect lines. Salt water showed great influence on ecological parameters of the native vegetation up to 40 m. Multivariate (cluster) analysis showed close clustering of highly salt tolerant species, Aeluropus lagopoides, Tamarix dioica and Suaeda fruticosa in one group, and relatively less tolerant Crotalaria burhia, Cyperus conglomeratus, Indigofera argentea, Haloxylon salicornicum, Haloxylon stocksii, Neurada procumbens and Salsola baryosma in second group. Moderately salt tolerant Aristida adscensionis, Lasiurus scindicus and Sporobolus iocladus were clustered in a separate group. (author)

  4. DIVERSITY in binding, regulation, and evolution revealed from high-throughput ChIP.

    Science.gov (United States)

    Mitra, Sneha; Biswas, Anushua; Narlikar, Leelavati

    2018-04-23

    Genome-wide in vivo protein-DNA interactions are routinely mapped using high-throughput chromatin immunoprecipitation (ChIP). ChIP-reported regions are typically investigated for enriched sequence-motifs, which are likely to model the DNA-binding specificity of the profiled protein and/or of co-occurring proteins. However, simple enrichment analyses can miss insights into the binding-activity of the protein. Note that ChIP reports regions making direct contact with the protein as well as those binding through intermediaries. For example, consider a ChIP experiment targeting protein X, which binds DNA at its cognate sites, but simultaneously interacts with four other proteins. Each of these proteins also binds to its own specific cognate sites along distant parts of the genome, a scenario consistent with the current view of transcriptional hubs and chromatin loops. Since ChIP will pull down all X-associated regions, the final reported data will be a union of five distinct sets of regions, each containing binding sites of one of the five proteins, respectively. Characterizing all five different motifs and the corresponding sets is important to interpret the ChIP experiment and ultimately, the role of X in regulation. We present diversity which attempts exactly this: it partitions the data so that each partition can be characterized with its own de novo motif. Diversity uses a Bayesian approach to identify the optimal number of motifs and the associated partitions, which together explain the entire dataset. This is in contrast to standard motif finders, which report motifs individually enriched in the data, but do not necessarily explain all reported regions. We show that the different motifs and associated regions identified by diversity give insights into the various complexes that may be forming along the chromatin, something that has so far not been attempted from ChIP data. Webserver at http://diversity.ncl.res.in/; standalone (Mac OS X/Linux) from https://github.com/NarlikarLab/DIVERSITY

  5. Occupational therapy's dance with diversity.

    Science.gov (United States)

    Black, Roxie M

    2002-01-01

    As the demographics of the United States continue to change and we become a more pluralistic society, the increased diversity of the occupational therapy workforce and our consumers calls for an examination of the profession's stance on multiculturalism and diversity. Using the metaphor of dance, this article identifies the dance partners as the organization's leaders and its members. A historical review of the profession from the 1940s to the present traces the partners' steps to determine which led the dance of diversity during the profession's development. In this review, I discovered that the period when the profession most effectively and productively explored issues of diversity was during the early- to mid-1990s--a time when the organization and its members worked in harmony. At that time, occupational therapy's dance with diversity flowed with rhythm and synchronicity.

  6. Multiplicity and diversity of Plasmodium vivax infections in a highly endemic region in Papua New Guinea.

    Directory of Open Access Journals (Sweden)

    Cristian Koepfli

    2011-12-01

    Full Text Available Plasmodium vivax is highly endemic in the lowlands of Papua New Guinea and accounts for a large proportion of the malaria cases in children less than 5 years of age. We collected 2117 blood samples at 2-monthly intervals from a cohort of 268 children aged 1 to 4.5 years and estimated the diversity and multiplicity of P. vivax infection. All P. vivax clones were genotyped using the merozoite surface protein 1 F3 fragment (msp1F3 and the microsatellite MS16 as molecular markers. High diversity was observed with msp1F3 (H(E = 88.1% and MS16 (H(E = 97.8%. Of the 1162 P. vivax positive samples, 74% harbored multi-clone infections with a mean multiplicity of 2.7 (IQR = 1-3. The multiplicity of P. vivax infection increased slightly with age (P = 0.02, with the strongest increase in very young children. Intensified efforts to control malaria can benefit from knowledge of the diversity and MOI both for assessing the endemic situation and monitoring the effects of interventions.

  7. Linking secondary metabolites to gene clusters through genome sequencing of six diverse Aspergillus species

    DEFF Research Database (Denmark)

    Kjærbølling, Inge; Vesth, Tammi C.; Frisvad, Jens C.

    2018-01-01

    The fungal genus of Aspergillus is highly interesting, containing everything from industrial cell factories, model organisms, and human pathogens. In particular, this group has a prolific production of bioactive secondary metabolites (SMs). In this work, four diverse Aspergillus species (A...

  8. High energy gamma-ray production in nuclear reactions

    International Nuclear Information System (INIS)

    Pinston, J.A.; Nifenecker, H.; Nifenecker, H.

    1989-01-01

    Experimental techniques used to study high energy gamma-ray production in nuclear reactions are reviewed. High energy photon production in nucleus-nucleus collisions is discussed. Semi-classical descriptions of the nucleus-nucleus gamma reactions are introduced. Nucleon-nucleon gamma cross sections are considered, including theoretical aspects and experimental data. High energy gamma ray production in proton-nucleus reactions is explained. Theoretical explanations of photon emission in nucleus-nucleus collisions are treated. The contribution of charged pion currents to photon production is mentioned

  9. A new combination of substrates: biogas production and diversity of the methanogenic microorganisms

    Directory of Open Access Journals (Sweden)

    Kushkevych Ivan

    2018-04-01

    Full Text Available Agriculture, food industry, and manufacturing are just some of the areas where anaerobic technology can be used. Currently, anaerobic technologies are mainly used for wastewater treatment, solid waste treatment, or for the production of electrical and thermal energy from energy crops processing. However, a clear trend is towards more intensive use of this technology in biomass and biodegradable waste processing and hydrogen or biomethane production. An enormous number of anaerobic digesters are operating worldwide but there is very little information about the effect of different substrate combinations on the methanogens community. This is due to the fact that each of the anaerobic digesters has its own unique microbial community. For the most effective management of anaerobic processes it would be important to know the composition of a consortium of anaerobic microorganisms present in anaerobic digesters processing different input combinations of raw material. This paper characterizes the effect of the input raw materials on the diversity of the methanogen community. Two predominant microorganisms in anaerobic digesters were found to be 99% identity by the sequences of the 16S rRNA gene to the Methanoculleus and Thermogymnomonas genera deposited in GenBank.

  10. A highly diverse, desert-like microbial biocenosis on solar panels in a Mediterranean city.

    Science.gov (United States)

    Dorado-Morales, Pedro; Vilanova, Cristina; Peretó, Juli; Codoñer, Francisco M; Ramón, Daniel; Porcar, Manuel

    2016-07-05

    Microorganisms colonize a wide range of natural and artificial environments although there are hardly any data on the microbial ecology of one the most widespread man-made extreme structures: solar panels. Here we show that solar panels in a Mediterranean city (Valencia, Spain) harbor a highly diverse microbial community with more than 500 different species per panel, most of which belong to drought-, heat- and radiation-adapted bacterial genera, and sun-irradiation adapted epiphytic fungi. The taxonomic and functional profiles of this microbial community and the characterization of selected culturable bacteria reveal the existence of a diverse mesophilic microbial community on the panels' surface. This biocenosis proved to be more similar to the ones inhabiting deserts than to any human or urban microbial ecosystem. This unique microbial community shows different day/night proteomic profiles; it is dominated by reddish pigment- and sphingolipid-producers, and is adapted to withstand circadian cycles of high temperatures, desiccation and solar radiation.

  11. Hydrogen Production Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The Hydrogen Production Technical Team Roadmap identifies research pathways leading to hydrogen production technologies that produce near-zero net greenhouse gas (GHG) emissions from highly efficient and diverse renewable energy sources. This roadmap focuses on initial development of the technologies, identifies their gaps and barriers, and describes activities by various U.S. Department of Energy (DOE) offices to address the key issues and challenges.

  12. Pyrosequencing Analysis of the Microbial Diversity of Airag, Khoormog and Tarag, Traditional Fermented Dairy Products of Mongolia

    OpenAIRE

    OKI, Kaihei; DUGERSUREN, Jamyan; DEMBEREL, Shirchin; WATANABE, Koichi

    2014-01-01

    Here, we used pyrosequencing to obtain a detailed analysis of the microbial diversities of traditional fermented dairy products of Mongolia. From 22 Airag (fermented mare’s milk), 5 Khoormog (fermented camel’s milk) and 26 Tarag (fermented milk of cows, goats and yaks) samples collected in the Mongolian provinces of Arhangai, Bulgan, Dundgobi, Tov, Uburhangai and Umnugobi, we obtained a total of 81 operational taxonomic units, which were assigned to 15 families, 21 genera and 41 species in 3 ...

  13. Functional diversity of soil invertebrates: a potential tool to explain N2O emission?

    Science.gov (United States)

    Lubbers, Ingrid; De Deyn, Gerlinde; Drake, Harold; Hunger, Sindy; Oppermann, Timo; van Groenigen, Jan Willem

    2017-04-01

    Soil biota play a crucial role in the mineralization of nutrients from organic material. However, they can thereby increase emissions of the potent greenhouse gas nitrous oxide (N2O). Our current lack of understanding of the factors controlling N2O production and emission is impeding the development of effective mitigation strategies. It is the challenge to control N2O emissions from production systems without reducing crop yield, and diversity of soil fauna may play a key role. A high functional diversity of soil invertebrates is known to stimulate nitrogen mineralization and thereby plant growth, however, it is unknown whether a high functional diversity of soil invertebrates can concurrently diminish N2O emissions. We hypothesized that increased functional diversity of soil invertebrates reduces faunal-induced N2O emissions by facilitating more complete denitrification through (i) stimulating the activity of denitrifying microbes, and (ii) affecting the distribution of micro and macro pores, creating more anaerobic reaction sites. Using state-of-the-art X-ray tomography and next-generation sequencing, we studied effects of functional diversity on soil structural properties and the diversity of the microbial community (16S rRNA genes and 16S rRNA), and linked these to soil N2O emissions. In a 120-day study we found that the functional composition of the soil invertebrate community determined N2O emissions: earthworm activity was key to faunal-induced N2O emissions (a 32-fold increase after 120 days, Pstructural properties (mean pore size, pore size distribution) were found to be radically altered by earthworm activity. We conclude that the presence of a few functional groups (ecosystem engineers) is more important than overall increased functional diversity in explaining faunal-affected N2O emissions.

  14. Multicontext Diversity: The critical dimension of diversity that can attract students and help them thrive

    Science.gov (United States)

    Weissmann, G. S.; Ibarra, R.; Howland-Davis, M.

    2017-12-01

    Diversity programs on college campuses have expanded over the past several decades, bringing a broad range of students to academia; however, these programs have not resulted in diversification of faculty or PhD students. Current diversity programs generally focus on two dimensions of diversity: (1) structural diversity, which aims to bring in students from underrepresented groups to college campuses through scholarships, admissions policies, and targeted marketing; and (2) multicultural diversity, which uses programs designed to give students from underrepresented groups homes on campus and programs designed to study cultural aspects of different groups. Though these programs are important, something else must be controlling the lack of minority participation in STEM at advanced levels. We posit that a third dimension of diversity, context diversity, is lacking in university education, especially in STEM fields, and without accessing this form of diversity, programs will never benefit from the broader diversity of society. Context diversity results through application of Multicontext theory, which both explains and predicts the inclusion of exclusion of people within an institutional culture. It describes how different cultures approach understanding the world around them. This "cultural ways of knowing and doing" has been described using a binary system, consisting of "Low Context" and "High Context" cultures. Ibarra (2001) described how a spectrum exists between these end members, and thus individuals brought up in different cultures will understand the world from somewhere along this context diversity spectrum. Academic culture tends to fall on the low context side of the spectrum. Thus, students (and faculty) who come from cultures that tend toward the high context side of the spectrum often feel excluded from the academic setting, especially in STEM fields which tend to be strongly low context in nature. A high percentage of students from underrepresented

  15. Sphagnum mosses harbour highly specific bacterial diversity during their whole lifecycle.

    Science.gov (United States)

    Bragina, Anastasia; Berg, Christian; Cardinale, Massimiliano; Shcherbakov, Andrey; Chebotar, Vladimir; Berg, Gabriele

    2012-04-01

    Knowledge about Sphagnum-associated microbial communities, their structure and their origin is important to understand and maintain climate-relevant Sphagnum-dominated bog ecosystems. We studied bacterial communities of two cosmopolitan Sphagnum species, which are well adapted to different abiotic parameters (Sphagnum magellanicum, which are strongly acidic and ombrotrophic, and Sphagnum fallax, which are weakly acidic and mesotrophic), in three Alpine bogs in Austria by a multifaceted approach. Great differences between bacterial fingerprints of both Sphagna were found independently from the site. This remarkable specificity was confirmed by a cloning and a deep sequencing approach. Besides the common Alphaproteobacteria, we found a discriminative spectrum of bacteria; although Gammaproteobacteria dominated S. magellanicum, S. fallax was mainly colonised by Verrucomicrobia and Planctomycetes. Using this information for fluorescent in situ hybridisation analyses, corresponding colonisation patterns for Alphaproteobacteria and Planctomycetes were detected. Bacterial colonies were found in high abundances inside the dead big hyalocytes, but they were always connected with the living chlorocytes. Using multivariate statistical analysis, the abiotic factors nutrient richness and pH were identified to modulate the composition of Sphagnum-specific bacterial communities. Interestingly, we found that the immense bacterial diversity was transferred via the sporophyte to the gametophyte, which can explain the high specificity of Sphagnum-associated bacteria over long distances. In contrast to higher plants, which acquire their bacteria mainly from the environment, mosses as the phylogenetically oldest land plants maintain their bacterial diversity within the whole lifecycle.

  16. Highly structured genetic diversity of the Mycobacterium tuberculosis population in Djibouti.

    Science.gov (United States)

    Godreuil, S; Renaud, F; Choisy, M; Depina, J J; Garnotel, E; Morillon, M; Van de Perre, P; Bañuls, A L

    2010-07-01

    Djibouti is an East African country with a high tuberculosis incidence. This study was conducted over a 2-month period in Djibouti, during which 62 consecutive patients with pulmonary tuberculosis (TB) were included. Genetic characterization of Mycobacterium tuberculosis, using mycobacterial interspersed repetitive-unit variable-number tandem-repeat typing and spoligotyping, was performed. The genetic and phylogenetic analysis revealed only three major families (Central Asian, East African Indian and T). The high diversity and linkage disequilibrium within each family suggest a long period of clonal evolution. A Bayesian approach shows that the phylogenetic structure observed in our sample of 62 isolates is very likely to be representative of the phylogenetic structure of the M. tuberculosis population in the total number of TB cases.

  17. Skeletal Diversity in Combinatorial Fashion: A New Format for the Castagnoli-Cushman Reaction.

    Science.gov (United States)

    Lepikhina, Anastasia; Dar'in, Dmitry; Bakulina, Olga; Chupakhin, Evgeny; Krasavin, Mikhail

    2017-11-13

    A new format for the Castagnoli-Cushman reaction of structurally diverse dicarboxylic acids, amines, and aldehydes in the presence of acetic anhydride as dehydrating agent is described. The reaction is distinctly amenable to parallel format: the combinatorial array of 180 reactions delivered 157 products of >85% purity without chromatographic purification (of this number, 143 compounds had >94% purity). The new method offers a convenient preparation of the skeletally and peripherally diverse, lead- and druglike γ- and δ-lactam carboxylic acids with high diastereoselectivity in combinatorial fashion.

  18. High frequency of phylogenetically diverse reductive dehalogenase-homologous genes in deep subseafloor sedimentary metagenomes

    Directory of Open Access Journals (Sweden)

    Mikihiko eKawai

    2014-03-01

    Full Text Available Marine subsurface sediments on the Pacific margin harbor diverse microbial communities even at depths of several hundreds meters below the seafloor (mbsf or more. Previous PCR-based molecular analysis showed the presence of diverse reductive dehalogenase gene (rdhA homologs in marine subsurface sediment, suggesting that anaerobic respiration of organohalides is one of the possible energy-yielding pathways in the organic-rich sedimentary habitat. However, primer-independent molecular characterization of rdhA has remained to be demonstrated. Here, we studied the diversity and frequency of rdhA homologs by metagenomic analysis of five different depth horizons (0.8, 5.1, 18.6, 48.5 and 107.0 mbsf at Site C9001 off the Shimokita Peninsula of Japan. From all metagenomic pools, remarkably diverse rdhA-homologous sequences, some of which are affiliated with novel clusters, were observed with high frequency. As a comparison, we also examined frequency of dissimilatory sulfite reductase genes (dsrAB, key functional genes for microbial sulfate reduction. The dsrAB were also widely observed in the metagenomic pools whereas the frequency of dsrAB genes was generally smaller than that of rdhA-homologous genes. The phylogenetic composition of rdhA-homologous genes was similar among the five depth horizons. Our metagenomic data revealed that subseafloor rdhA homologs are more diverse than previously identified from PCR-based molecular studies. Spatial distribution of similar rdhA homologs across wide depositional ages indicates that the heterotrophic metabolic processes mediated by the genes can be ecologically important, functioning in the organic-rich subseafloor sedimentary biosphere.

  19. Genetic diversity of dispersed seeds is highly variable among leks of the long-wattled umbrellabird

    Science.gov (United States)

    Ottewell, Kym; Browne, Luke; Cabrera, Domingo; Olivo, Jorge; Karubian, Jordan

    2018-01-01

    Frugivorous animals frequently generate clumped distributions of seeds away from source trees, but genetic consequences of this phenomenon remain poorly resolved. Seed dispersal of the palm Oenocarpus bataua by long-wattled umbrellabirds Cephalopterus penduliger generates high seed densities in leks (i.e., multi-male display sites), providing a suitable venue to investigate how dispersal by this frugivore may influence seed source diversity and genetic structure at local and landscape levels. We found moderate levels of maternal seed source diversity in primary seed rain across five leks in northwest Ecuador (unweighted mean alpha diversity α = 9.52, weighted mean αr = 3.52), with considerable variation among leks (αr range: 1.81-24.55). Qualitatively similar findings were obtained for allelic diversity and heterozygosity. Higher densities of O. bataua adults around leks were associated with higher values of αr and heterozygosity (non-significant trends) and allelic diversity (significant correlation). Seed source overlap between different leks was not common but did occur at low frequency, providing evidence for long-distance seed dispersal by umbrellabirds into leks. Our findings are consistent with the idea that seed pool diversity within leks may be shaped by the interaction between density of local trees, which can vary considerably between leks, and umbrellabird foraging ecology, particularly a lack of territorial defense of fruiting trees. Taken as a whole, this work adds to our growing appreciation of the ways resource distribution and associated frugivore foraging behaviors mechanistically shape seed dispersal outcomes and the distribution of plant genotypes across the landscape.

  20. Assessing the drug-likeness of lamellarins, a marine-derived natural product class with diverse oncological activities.

    Science.gov (United States)

    Chittchang, Montakarn; Gleeson, M Paul; Ploypradith, Poonsakdi; Ruchirawat, Somsak

    2010-06-01

    Natural products currently represent an underutilized source of leads for the pharmaceutical industry, especially when one considers that almost 50% of all drugs were either derived from such sources or are very closely related. Lamellarins are a class of natural products with diverse biological activities and have entered into preclinical development for the treatment of multidrug-resistant tumors. Although these compounds demonstrated good cell penetration, as observed by their low microM activity in whole cell models, they have not been extensively profiled from a physicochemical point of view, and this is the goal of this study. For this study, we have determined the experimental logP values of a set of 25 lamellarins, given it is the single most important parameter in determining multiple ADMET parameters. We also discuss the relationship between this natural product class, natural product derivatives in development and on the market, oral marketed drugs, as well as drug molecules in development, using a range of physicochemical parameters in conjunction with principal components analysis (PCA). The impact of this systematic analysis on our ongoing medicinal chemistry strategy is also discussed. Copyright (c) 2010 Elsevier Masson SAS. All rights reserved.

  1. Diversity and stability of coral endolithic microbial communities at a naturally high pCO2 reef.

    Science.gov (United States)

    Marcelino, Vanessa Rossetto; Morrow, Kathleen M; van Oppen, Madeleine J H; Bourne, David G; Verbruggen, Heroen

    2017-10-01

    The health and functioning of reef-building corals is dependent on a balanced association with prokaryotic and eukaryotic microbes. The coral skeleton harbours numerous endolithic microbes, but their diversity, ecological roles and responses to environmental stress, including ocean acidification (OA), are not well characterized. This study tests whether pH affects the diversity and structure of prokaryotic and eukaryotic algal communities associated with skeletons of Porites spp. using targeted amplicon (16S rRNA gene, UPA and tufA) sequencing. We found that the composition of endolithic communities in the massive coral Porites spp. inhabiting a naturally high pCO 2 reef (avg. pCO 2 811 μatm) is not significantly different from corals inhabiting reference sites (avg. pCO 2 357 μatm), suggesting that these microbiomes are less disturbed by OA than previously thought. Possible explanations may be that the endolithic microhabitat is highly homeostatic or that the endolithic micro-organisms are well adapted to a wide pH range. Some of the microbial taxa identified include nitrogen-fixing bacteria (Rhizobiales and cyanobacteria), algicidal bacteria in the phylum Bacteroidetes, symbiotic bacteria in the family Endozoicomoniaceae, and endolithic green algae, considered the major microbial agent of reef bioerosion. Additionally, we test whether host species has an effect on the endolithic community structure. We show that the endolithic community of massive Porites spp. is substantially different and more diverse than that found in skeletons of the branching species Seriatopora hystrix and Pocillopora damicornis. This study reveals highly diverse and structured microbial communities in Porites spp. skeletons that are possibly resilient to OA. © 2017 John Wiley & Sons Ltd.

  2. A phylogenetic perspective on species diversity, β-diversity and biogeography for the microbial world.

    Science.gov (United States)

    Barberán, Albert; Casamayor, Emilio O

    2014-12-01

    There is an increasing interest to combine phylogenetic data with distributional and ecological records to assess how natural communities arrange under an evolutionary perspective. In the microbial world, there is also a need to go beyond the problematic species definition to deeply explore ecological patterns using genetic data. We explored links between evolution/phylogeny and community ecology using bacterial 16S rRNA gene information from a high-altitude lakes district data set. We described phylogenetic community composition, spatial distribution, and β-diversity and biogeographical patterns applying evolutionary relatedness without relying on any particular operational taxonomic unit definition. High-altitude lakes districts usually contain a large mosaic of highly diverse small water bodies and conform a fine biogeographical model of spatially close but environmentally heterogeneous ecosystems. We sampled 18 lakes in the Pyrenees with a selection criteria focused on capturing the maximum environmental variation within the smallest geographical area. The results showed highly diverse communities nonrandomly distributed with phylogenetic β-diversity patterns mainly shaped by the environment and not by the spatial distance. Community similarity based on both bacterial taxonomic composition and phylogenetic β-diversity shared similar patterns and was primarily structured by similar environmental drivers. We observed a positive relationship between lake area and phylogenetic diversity with a slope consistent with highly dispersive planktonic organisms. The phylogenetic approach incorporated patterns of common ancestry into bacterial community analysis and emerged as a very convenient analytical tool for direct inter- and intrabiome biodiversity comparisons and sorting out microbial habitats with potential application in conservation studies. © 2014 John Wiley & Sons Ltd.

  3. Production of high-specific activity radionuclides using SM high-flux reactor

    International Nuclear Information System (INIS)

    Karelin, Ye.A.; Toporov, Yu.G.; Filimonov, V.T.; Vakhetov, F.Z.; Tarasov, V.A.; Kuznetsov, R.A.; Lebedev, V.M.; Andreev, O.I.; Melnik, M.I.; Gavrilov, V.D.

    1997-01-01

    The development of High Specific Activity (HSA) radionuclides production technologies is one of the directions of RIAR activity, and the high flux research reactor SM, having neutron flux density up to 2.10 15 cm -2 s 1 in a wide range of neutron spectra hardness, plays the principal role in this development. The use of a high-flux reactor for radionuclide production provides the following advantages: production of radionuclides with extremely high specific activity, decreasing of impurities content in irradiated targets (both radioactive and non-radioactive), cost-effective use of expensive isotopically enriched target materials. The production technologies of P-33, Gd-153, W-188, Ni-63, Fe-55,59, Sn-113,117m,119m, Sr- 89, applied in industry, nuclear medicine, research, etc, were developed by RIAR during the last 5-10 years. The research work included the development of calculation procedures for radionuclide reactor accumulation forecast, experimental determination of neutron cross-sections, the development of irradiated materials reprocessing procedures, isolation and purification of radionuclides. The principal results are reviewed in the paper. (authors)

  4. Genetic diversity, phylogeographic structure and effect of selection ...

    Indian Academy of Sciences (India)

    Abdulhakeem B. Ajibike

    2017-12-11

    Dec 11, 2017 ... RESEARCH ARTICLE. Genetic diversity, phylogeographic ... chickens as genetic resources towards ensuring food security. Keywords. genetic diversity ... PCR product as template DNA, 3.2 pmol of primer and. 8 μL of Big Dye ...

  5. In silico and experimental methods revealed highly diverse bacteria with quorum sensing and aromatics biodegradation systems--a potential broad application on bioremediation.

    Science.gov (United States)

    Huang, Yili; Zeng, Yanhua; Yu, Zhiliang; Zhang, Jing; Feng, Hao; Lin, Xiuchun

    2013-11-01

    Phylogenetic overlaps between aromatics-degrading bacteria and acyl-homoserine-lactone (AHL) or autoinducer (AI) based quorum-sensing (QS) bacteria were evident in literatures; however, the diversity of bacteria with both activities had never been finely described. In-silico searching in NCBI genome database revealed that more than 11% of investigated population harbored both aromatic ring-hydroxylating-dioxygenase (RHD) gene and AHL/AI-synthetase gene. These bacteria were distributed in 10 orders, 15 families, 42 genus and 78 species. Horizontal transfers of both genes were common among them. Using enrichment and culture dependent method, 6 Sphingomonadales and 4 Rhizobiales with phenanthrene- or pyrene-degrading ability and AHL-production were isolated from marine, wetland and soil samples. Thin-layer-chromatography and gas-chromatography-mass-spectrum revealed that these Sphingomonads produced various AHL molecules. This is the first report of highly diverse bacteria that harbored both aromatics-degrading and QS systems. QS regulation may have broad impacts on aromatics biodegradation, and would be a new angle for developing bioremediation technology. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. High genetic diversity and fine-scale spatial structure in the marine flagellate Oxyrrhis marina (Dinophyceae uncovered by microsatellite loci.

    Directory of Open Access Journals (Sweden)

    Chris D Lowe

    2010-12-01

    Full Text Available Free-living marine protists are often assumed to be broadly distributed and genetically homogeneous on large spatial scales. However, an increasing application of highly polymorphic genetic markers (e.g., microsatellites has provided evidence for high genetic diversity and population structuring on small spatial scales in many free-living protists. Here we characterise a panel of new microsatellite markers for the common marine flagellate Oxyrrhis marina. Nine microsatellite loci were used to assess genotypic diversity at two spatial scales by genotyping 200 isolates of O. marina from 6 broad geographic regions around Great Britain and Ireland; in one region, a single 2 km shore line was sampled intensively to assess fine-scale genetic diversity. Microsatellite loci resolved between 1-6 and 7-23 distinct alleles per region in the least and most variable loci respectively, with corresponding variation in expected heterozygosities (H(e of 0.00-0.30 and 0.81-0.93. Across the dataset, genotypic diversity was high with 183 genotypes detected from 200 isolates. Bayesian analysis of population structure supported two model populations. One population was distributed across all sampled regions; the other was confined to the intensively sampled shore, and thus two distinct populations co-occurred at this site. Whilst model-based analysis inferred a single UK-wide population, pairwise regional F(ST values indicated weak to moderate population sub-division (0.01-0.12, but no clear correlation between spatial and genetic distance was evident. Data presented in this study highlight extensive genetic diversity for O. marina; however, it remains a substantial challenge to uncover the mechanisms that drive genetic diversity in free-living microorganisms.

  7. Organisational Diversity and Knowledge Sharing

    DEFF Research Database (Denmark)

    Lauring, Jakob; Jonasson, Charlotte

    productivity and diversity management - that is not engaging in a discussion of how and why there could be potential benefits or difficulties. In this paper we will describe and analyse some of the complications multicultural organisations can experience in regard to knowledge sharing......The last years' focus on diversity management has gone from social responsibility to arguments for the competitive advantages, called the business case. It has been argued that diversity management can increase organisational efficiency, improve on moral, and give better access to new market...... segments. But a substantial critique has recently been launched at the arguments for the business case for diversity, especially in the employment of knowledge synergies. Most studies that support or reject the business case argument have limited their research to establish a link between organisational...

  8. Disclosure Experiences of Urban, Ethnically Diverse LGBT High School Students: Implications for School Personnel

    Science.gov (United States)

    Varjas, Kris; Kiperman, Sarah; Meyers, Joel

    2016-01-01

    Disclosure of sexual orientation and/or gender identity is a milestone event for lesbian, gay, bisexual, or transgender (LGBT) youth and can have both positive and negative mental health consequences. Twenty-nine urban, ethnically diverse LGBT high school students participated in face-to-face, in-depth interviews. Qualitative results revealed two…

  9. Diversity-Guided Evolutionary Algorithms

    DEFF Research Database (Denmark)

    Ursem, Rasmus Kjær

    2002-01-01

    Population diversity is undoubtably a key issue in the performance of evolutionary algorithms. A common hypothesis is that high diversity is important to avoid premature convergence and to escape local optima. Various diversity measures have been used to analyze algorithms, but so far few...... algorithms have used a measure to guide the search. The diversity-guided evolutionary algorithm (DGEA) uses the wellknown distance-to-average-point measure to alternate between phases of exploration (mutation) and phases of exploitation (recombination and selection). The DGEA showed remarkable results...

  10. Hydrogen Production from Nuclear Energy via High Temperature Electrolysis

    International Nuclear Information System (INIS)

    James E. O'Brien; Carl M. Stoots; J. Stephen Herring; Grant L. Hawkes

    2006-01-01

    This paper presents the technical case for high-temperature nuclear hydrogen production. A general thermodynamic analysis of hydrogen production based on high-temperature thermal water splitting processes is presented. Specific details of hydrogen production based on high-temperature electrolysis are also provided, including results of recent experiments performed at the Idaho National Laboratory. Based on these results, high-temperature electrolysis appears to be a promising technology for efficient large-scale hydrogen production

  11. Urban Household Characteristics and Dietary Diversity: An Analysis of Food Security in Accra, Ghana.

    Science.gov (United States)

    Codjoe, Samuel Nii Ardey; Okutu, David; Abu, Mumuni

    2016-06-01

    The world's population is increasingly becoming urbanized. If the current urban growth rate is to continue, new and unprecedented challenges for food security will be inevitable. Dietary diversity has been used to ascertain food security status albeit at the multicountry and country levels. Thus, household-level studies in urban settings, particularly in sub-Sahara African, are few. Yet, it is imperative that assessments of food security are undertaken particularly in urban settings, due to the projected fast rate of urbanization and the challenges of attaining food security. To examine household characteristics and dietary diversity. The study uses data from 452 households from the second round of the Regional Institute for Population Studies (RIPS) EDULINK urban poverty and health study. Bivariate and multivariate analyses are undertaken. Mean dietary diversity for all households is 6.8. Vegetables have the highest diversity, followed by cereal-based and grain products. Household characteristics that have statistically significant associations with dietary diversity include sex and level of education of household head, household wealth quintile, and source of food. There is high dietary diversity in the study communities of Accra but low consumption of foods rich in micronutrient, such as fruits and milk/dairy products. The study brings to fore issues related to resource-disadvantaged entities of the urban system, namely, females, poor households, and the non-educated who have food insecurity problems. © The Author(s) 2016.

  12. Validation of Product Properties Considering a High Variety of Complex Products

    OpenAIRE

    Kortler, S.;Kohn, A.;Lindemann, U.

    2017-01-01

    Validation processes are becoming more and more complex. Due to rising technical capabilities and a wide variety of customer requirements, OEMs are increasing their product variety in order to increase profits. According to the various characteristics of subcontracted components involved in complex products, the product variety can be very high. The impacts of the involved subcontracted components on the composed product variety during the product’s application are difficult to predict. This ...

  13. Diverse by Default

    DEFF Research Database (Denmark)

    Holck, Lotte

    arguments that arise from migrants’ paradoxical situation. To improve their situation, the article discusses whether alternative conceptualization of talents, ‘high potentials’, and making the ambitions of diverse employees more prominent in strategic human resource management can be a relavant strategy......: Employing highlyskilled, career-minded migrants in low-skilled postions, migrants are simultaneously casted as a disposable, replicable and temporary resource, the ‘ideal worker’, AND as a ‘high potential’ for first line management. This extended business case of diversity draws on multifaceted business......This paper contributes to theoretical debates around migrant workers at the workplace, labour market inequality and the business case of diversity. Building on stories of overqualified migrant stuck in low-rank jobs due to their migration, this paper explores how migrant workers are simultaneous...

  14. What makes age diverse teams effective? Results from a six-year research program.

    Science.gov (United States)

    Wegge, J; Jungmann, F; Liebermann, S; Shemla, M; Ries, B C; Diestel, S; Schmidt, K-H

    2012-01-01

    Based on a new model of productivity in age diverse tams, findings from a six-year research program are reported in which data from more than 745 natural teams with 8,848 employees in three different fields (car production, administrative work, financial services) were collected. Moreover, central assumptions of this model were tested with a representative survey of the German workforce (N = 2,000). Results support both significant advantages and disadvantages for age-mixed teams. Based on the findings, the following preconditions for the effectiveness of age diverse teams are identified: high task complexity, low salience and high appreciation of age diversity, a positive team climate, low age-discrimination, ergonomic design of work places, and the use of age differentiated leadership. Based on these insights, we developed a new training for supervisors, which addresses the aforementioned aspects and seeks to improve team performance and health of team members. It was found that the training reduces age stereotypes, team conflicts and enhances innovation. Thus, we can conclude that effective interventions for a successful integration of elderly employees in work groups are available and that combinations of measures that address ergonomic design issues, team composition and leadership are to be strongly recommended for practice.

  15. [Elaboration of Pseudo-natural Products Using Artificial In Vitro Biosynthesis Systems].

    Science.gov (United States)

    Goto, Yuki

    2018-01-01

     Peptidic natural products often consist of not only proteinogenic building blocks but also unique non-proteinogenic structures such as macrocyclic scaffolds and N-methylated backbones. Since such non-proteinogenic structures are important structural motifs that contribute to diverse bioactivity, we have proposed that peptides with non-proteinogenic structures should be attractive candidates as artificial bioactive peptides mimicking natural products, or so-called pseudo-natural products. We previously devised an engineered translation system for pseudo-natural peptides, referred to as the flexible in vitro translation (FIT) system. This system enabled "one-pot" synthesis of highly diverse pseudo-natural peptide libraries, which can be rapidly screened by mRNA display technology for the discovery of pseudo-natural peptides with diverse bioactivities.

  16. Species dispersal rates alter diversity and ecosystem stability in pond metacommunities.

    Science.gov (United States)

    Howeth, Jennifer G; Leibold, Mathew A

    2010-09-01

    Metacommunity theory suggests that relationships between diversity and ecosystem stability can be determined by the rate of species dispersal among local communities. The predicted relationships, however, may depend upon the relative strength of local environmental processes and disturbance. Here we evaluate the role of dispersal frequency and local predation perturbations in affecting patterns of diversity and stability in pond plankton metacommunities. Pond metacommunities were composed of three mesocosm communities: one of the three communities maintained constant "press" predation from a selective predator, bluegill sunfish (Lepomis macrochirus); the second community maintained "press" conditions without predation; and the third community experienced recurrent "pulsed" predation from bluegill sunfish. The triads of pond communities were connected at either no, low (0.7%/d), or high (20%/d) planktonic dispersal. Richness and composition of zooplankton and stability of plankton biomass and ecosystem productivity were measured at local and regional spatial scales. Dispersal significantly affected diversity such that local and regional biotas at the low dispersal rate maintained the greatest number of species. The unimodal local dispersal-diversity relationship was predator-dependent, however, as selective press predation excluded species regardless of dispersal. Further, there was no effect of dispersal on beta diversity because predation generated local conditions that selected for distinct community assemblages. Spatial and temporal ecosystem stability responded to dispersal frequency but not predation. Low dispersal destabilized the spatial stability of producer biomass but stabilized temporal ecosystem productivity. The results indicate that selective predation can prevent species augmentation from mass effects but has no apparent influence on stability. Dispersal rates, in contrast, can have significant effects on both species diversity and ecosystem

  17. Listeria monocytogenes serotype prevalence and biodiversity in diverse food products.

    Science.gov (United States)

    Hadjilouka, Agni; Andritsos, Nikolaos D; Paramithiotis, Spiros; Mataragas, Marios; Drosinos, Eleftherios H

    2014-12-01

    The aim of this study was to assess serotype prevalence and biodiversity of Listeria monocytogenes strains isolated from diverse food products, i.e., minced pork, fruits, and vegetables. Three hundred twenty-six samples previously purchased from supermarkets and street markets within the Athens area were studied for L. monocytogenes prevalence. A total of 121 strains were isolated from the 36 samples that were positive for L. monocytogenes. Serotyping was performed with multiplex PCR, and biodiversity was assessed with random amplified polymorphic DNA (RAPD) PCR analysis using M13, UBC155, and HLWL85 as primers and with repetitive element palindromic (rep) PCR analysis using (GTG)5 as the primer. The majority (17 of 22) of the contaminated minced pork samples contained strains identified as serotype 1/2a, either alone or in combination with strains belonging to serotypes 1/2b, 4a, 4c, or 4ab. However, all L. monocytogenes isolates from fruits and vegetables belonged to serotype 4b. Rep-PCR provided better differentiation of the isolates than did RAPD PCR and resulted in discrimination of the isolates into a larger number of unique profiles. Complete differentiation was achieved only with the combination of these subtyping techniques.

  18. Multilocus genotypic data reveal high genetic diversity and low population genetic structure of Iranian indigenous sheep

    International Nuclear Information System (INIS)

    Vahidi, S.M.F.; Faruque, M.O.; Falahati Anbaran, M.; Afraz, F.; Mousavi, S.M.; Boettcher, P.; Joost, S.; Han, J.L.; Colli, L.; Periasamy, K.; Negrini, R.; Ajmone-Marsan, P.

    2016-01-01

    Full text: Iranian livestock diversity is still largely unexplored, in spite of the interest in the populations historically reared in this country located near the Fertile Crescent, a major livestock domestication centre. In this investigation, the genetic diversity and differentiation of 10 Iranian indigenous fat-tailed sheep breeds were investigated using 18 microsatellite markers. Iranian breeds were found to host a high level of diversity. This conclusion is substantiated by the large number of alleles observed across loci (average 13.83, range 7–22) and by the high within-breed expected heterozygosity (average 0.75, range 0.72–0.76). Iranian sheep have a low level of genetic differentiation, as indicated by the analysis of molecular variance, which allocated a very small proportion (1.67%) of total variation to the between-population component, and by the small fixation index (FST = 0.02). Both Bayesian clustering and principal coordinates analysis revealed the absence of a detectable genetic structure. Also, no isolation by distance was observed through comparison of genetic and geographical distances. In spite of high within-breed variation, signatures of inbreeding were detected by the FIS indices, which were positive in all and statistically significant in three breeds. Possible factors explaining the patterns observed, such as considerable gene flow and inbreeding probably due to anthropogenic activities in the light of population management and conservation programmes are discussed. (author)

  19. Diversity of protists and bacteria determines predation performance and stability.

    Science.gov (United States)

    Saleem, Muhammad; Fetzer, Ingo; Harms, Hauke; Chatzinotas, Antonis

    2013-10-01

    Predation influences prey diversity and productivity while it effectuates the flux and reallocation of organic nutrients into biomass at higher trophic levels. However, it is unknown how bacterivorous protists are influenced by the diversity of their bacterial prey. Using 456 microcosms, in which different bacterial mixtures with equal initial cell numbers were exposed to single or multiple predators (Tetrahymena sp., Poterioochromonas sp. and Acanthamoeba sp.), we showed that increasing prey richness enhanced production of single predators. The extent of the response depended, however, on predator identity. Bacterial prey richness had a stabilizing effect on predator performance in that it reduced variability in predator production. Further, prey richness tended to enhance predator evenness in the predation experiment including all three protists predators (multiple predation experiment). However, we also observed a negative relationship between prey richness and predator production in multiple predation experiments. Mathematical analysis of potential ecological mechanisms of positive predator diversity-functioning relationships revealed predator complementarity as a factor responsible for both enhanced predator production and prey reduction. We suggest that the diversity at both trophic levels interactively determines protistan performance and might have implications in microbial ecosystem processes and services.

  20. Species diversity of plant communities from territories with natural origin radionuclides contamination

    Energy Technology Data Exchange (ETDEWEB)

    Kaneva, A.V.; Belykh, E.S.; Maystrenko, T.A.; Grusdev, B.I.; Zainullin, V.G.; Vakhrusheva, O.M. [Institute of Biology, Komi Scientific Center, Ural Division of RAS, Syktyvkar, 167982 (Russian Federation); Oughton, D. [Norwegian University of Life Sciences, P.O. Box 5003, NO-1432 Aas (Norway)

    2014-07-01

    Since plants dominate every landscape, the impact of any environmental stressor on plants can directly affect the structure and function of an ecosystem, resulting in decreased primary productivity and degradation of wildlife habitat. The investigation goal of the present research was to study how vascular plant species' composition at a former radium mining site could be related to i) soil contamination with heavy metals and uranium and thorium decay chain radionuclides and ii) soil agrochemical properties. Between the 1930's and 1950's, the commercial extraction of radium, storage of the uranium mill tailings and radium production wastes, together with deactivation of the site with a mixture of sand and gravel completely destroyed plant communities in the vicinity of Vodny settlement (Komi Republic, Russia). The plant cover recovery started more than 60 years ago, and resulted in overgrowing with common grassland plant species. Three meadow sites were investigated, one with low contamination (on the territory of former radium production plant), one with high contamination (waste storage cell) and a reference sites out of the radiochemical plant zone of influence, but with similar natural conditions. Geo-botanical descriptions revealed 134 vascular plant species from 34 families in the meadow communities studied. The greatest richness was seen for Poaceae, Asteraceae, Rosaceae and Fabaceae families; others had 1-5 species. The highest richness in diversity was seen at reference sites with 95 vascular plant species. 87 species were registered on low contaminated sites and 75 species on high contaminated. Perennial herbs were the dominant life form on all the studied meadow communities. Arboreal species expansion in vegetation was noted at both experimental and reference sites. Shannon index calculations indicated a significant (p<0.05) decrease in species diversity on sample areas of the highly contaminated radioactive waste storage cell. Mean values

  1. Dynamics of Phylogenetic Diversity and Its Influence on the Production of Extracellular Protease by Moderately Halotolerant Alkaliphilic Bacteria Acinetobacter Baumannii GTCR407 Nov

    Directory of Open Access Journals (Sweden)

    Thiyagarajan Gurunathan

    2010-07-01

    Full Text Available New characters emerge in the population of microorganisms living in the extreme environments due to its adaptation to ecological association. The microorganisms living in saline habitat utilize complex nutrients by adopting different strategies in Deoxyribonucleic Acid (DNA and Ribonucleic Acid (RNA, which are related to their metabolic and ecological diversities. Isolation and characterization of the organisms producing extracellular protease from such environment were the prime focus of this investigation, which can indicate the importance of metabolic diversity in phylogeny. Norberg medium was used to isolate halotolerant microorganisms from salt-cured skin. The isolates were screened for high activity of protease and the strain showing maximum activity of protease was taken for further studies. The biochemical characterization and 16s ribosomal RNA sequencing studies confirm that the isolate is Acinetobacter baumannii. Moreover, hydrolysis positive for starch and casein, negative for gelatin shows that the organism is a variant form of A. baumannii. Cell growth parameters such as pH and temperature were optimized and their values are 8 and 37oC respectively. The extracellular production of protease was optimized in the suitable medium and its enzyme activity was 165μg/ml/min. The results imply that the isolate had acquired operational genes through lateral gene transfer (LGT probably from unrelated species in the environment. This indicates that the isolate identified possesses metabolic and ecological diversities with values of phylogenetic delineation

  2. Rare earth magnets with high energy products

    International Nuclear Information System (INIS)

    Hirosawa, S.; Kaneko, Y.

    1998-01-01

    High energy-products exceeding 430 kj/m 3 (54 MGOe) have been realized on anisotropic permanent magnets based on the Nd 2 Fe 14 B phase, recently. To produce extremely high-energy-product permanent magnets, special processes have been designed in order to realize the minimum oxygen content, the maximum volume fraction of the hard magnetic Nd 2 Fe 14 B phase, the highest orientation of the easy axis of magnetization, and small and homogeneous crystalline grain sizes in the finished magnets. For the powder metallurgical process, special techniques such as low-oxygen fine powder processing and magnetic alignment using pulsed magnetic fields have been developed. It has been shown that a good control of both homogeneity of distribution of constituent phases and the narrowness of the size distribution in the starting powder have great influences on the magnetic energy products. It is emphasized that the recently developed techniques are applicable in a large-scale production, meaning that extremely high-energy-product magnets are available on commercial basis. (orig.)

  3. Genetic Diversity in Jatropha curcas L. Assessed with SSR and SNP Markers

    Directory of Open Access Journals (Sweden)

    Juan M. Montes

    2014-08-01

    Full Text Available Jatropha curcas L. (jatropha is an undomesticated plant that has recently received great attention for its utilization in biofuel production, rehabilitation of wasteland, and rural development. Knowledge of genetic diversity and marker-trait associations is urgently needed for the design of breeding strategies. The main goal of this study was to assess the genetic structure and diversity in jatropha germplasm with co-dominant markers (Simple Sequence Repeats (SSR and Single Nucleotide Polymorphism (SNP in a diverse, worldwide, germplasm panel of 70 accessions. We found a high level of homozygosis in the germplasm that does not correspond to the purely outcrossing mating system assumed to be present in jatropha. We hypothesize that the prevalent mating system of jatropha comprise a high level of self-fertilization and that the outcrossing rate is low. Genetic diversity in accessions from Central America and Mexico was higher than in accession from Africa, Asia, and South America. We identified makers associated with the presence of phorbol esters. We think that the utilization of molecular markers in breeding of jatropha will significantly accelerate the development of improved cultivars.

  4. Does genetic diversity hinder parasite evolution in social insect colonies?

    DEFF Research Database (Denmark)

    Hughes, William Owen Hamar; Boomsma, Jacobus Jan

    2006-01-01

    of host genetic diversity on parasite evolution by carrying out serial passages of a virulent fungal pathogen through leaf-cutting ant workers of known genotypes. Parasite virulence increased over the nine-generation span of the experiment while spore production decreased. The effect of host relatedness...... upon virulence appeared limited. However, parasites cycled through more genetically diverse hosts were more likely to go extinct during the experiment and parasites cycled through more genetically similar hosts had greater spore production. These results indicate that host genetic diversity may indeed...

  5. Integrative Production Technology for High-Wage Countries

    CERN Document Server

    2012-01-01

    Industrial production in high-wage countries like Germany is still at risk. Yet, there are many counter-examples in which producing companies dominate their competitors by not only compensating for their specific disadvantages in terms of factor costs (e.g. wages, energy, duties and taxes) but rather by minimising waste using synchronising integrativity as well as by obtaining superior adaptivity on alternating conditions. In order to respond to the issue of economic sustainability of industrial production in high-wage countries, the leading production engineering and material research scientists of RWTH Aachen University together with renowned companies have established the Cluster of Excellence “Integrative Production Technology for High-Wage Countries”. This compendium comprises the cluster’s scientific results as well as a selection of business and technology cases, in which these results have been successfully implemented into industrial practice in close cooperation with more than 30 companies of ...

  6. Pyrosequencing reveals highly diverse and species-specific microbial communities in sponges from the Red Sea

    KAUST Repository

    Lee, Onon

    2010-11-18

    Marine sponges are associated with a remarkable array of microorganisms. Using a tag pyrosequencing technology, this study was the first to investigate in depth the microbial communities associated with three Red Sea sponges, Hyrtios erectus, Stylissa carteri and Xestospongia testudinaria. We revealed highly diverse sponge-associated bacterial communities with up to 1000 microbial operational taxonomic units (OTUs) and richness estimates of up to 2000 species. Altogether, 26 bacterial phyla were detected from the Red Sea sponges, 11 of which were absent from the surrounding sea water and 4 were recorded in sponges for the first time. Up to 100 OTUs with richness estimates of up to 300 archaeal species were revealed from a single sponge species. This is by far the highest archaeal diversity ever recorded for sponges. A non-negligible proportion of unclassified reads was observed in sponges. Our results demonstrated that the sponge-associated microbial communities remained highly consistent in the same sponge species from different locations, although they varied at different degrees among different sponge species. A significant proportion of the tag sequences from the sponges could be assigned to one of the sponge-specific clusters previously defined. In addition, the sponge-associated microbial communities were consistently divergent from those present in the surrounding sea water. Our results suggest that the Red Sea sponges possess highly sponge-specific or even sponge-species-specific microbial communities that are resistant to environmental disturbance, and much of their microbial diversity remains to be explored. © 2011 International Society for Microbial Ecology All rights reserved.

  7. Unexpected absence of genetic separation of a highly diverse population of hookworms from geographically isolated hosts.

    Science.gov (United States)

    Haynes, Benjamin T; Marcus, Alan D; Higgins, Damien P; Gongora, Jaime; Gray, Rachael; Šlapeta, Jan

    2014-12-01

    The high natal site fidelity of endangered Australian sea lions (Neophoca cinerea) along the southern Australian coast suggests that their maternally transmitted parasitic species, such as hookworms, will have restricted potential for dispersal. If this is the case, we would expect to find a hookworm haplotype structure corresponding to that of the host mtDNA haplotype structure; that is, restricted among geographically separated colonies. In this study, we used a fragment of the cytochrome c oxidase I mitochondrial DNA (mtDNA) gene to investigate the diversity of hookworms (Uncinaria sanguinis) in N. cinerea to assess the importance of host distribution and ecology on the evolutionary history of the parasite. High haplotype (h=0.986) and nucleotide diversity (π=0.013) were seen, with 45 unique hookworm mtDNA haplotypes across N. cinerea colonies; with most of the variation (78%) arising from variability within hookworms from individual colonies. This is supported by the low genetic differentiation co-efficient (GST=0.007) and a high gene flow (Nm=35.25) indicating a high migration rate between the populations of hookworms. The haplotype network demonstrated no clear distribution and delineation of haplotypes according to geographical location. Our data rejects the vicariance hypothesis; that female host natal site fidelity and the transmammary route of infection restrict hookworm gene flow between N. cinerea populations and highlights the value of studies of parasite diversity and dispersal to challenge our understanding of parasite and host ecology. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. High Diversity of Myocyanophage in Various Aquatic Environments Revealed by High-Throughput Sequencing of Major Capsid Protein Gene With a New Set of Primers

    Directory of Open Access Journals (Sweden)

    Weiguo Hou

    2018-05-01

    Full Text Available Myocyanophages, a group of viruses infecting cyanobacteria, are abundant and play important roles in elemental cycling. Here we investigated the particle-associated viral communities retained on 0.2 μm filters and in sediment samples (representing ancient cyanophage communities from four ocean and three lake locations, using high-throughput sequencing and a newly designed primer pair targeting a gene fragment (∼145-bp in length encoding the cyanophage gp23 major capsid protein (MCP. Diverse viral communities were detected in all samples. The fragments of 142-, 145-, and 148-bp in length were most abundant in the amplicons, and most sequences (>92% belonged to cyanophages. Additionally, different sequencing depths resulted in different diversity estimates of the viral community. Operational taxonomic units obtained from deep sequencing of the MCP gene covered the majority of those obtained from shallow sequencing, suggesting that deep sequencing exhibited a more complete picture of cyanophage community than shallow sequencing. Our results also revealed a wide geographic distribution of marine myocyanophages, i.e., higher dissimilarities of the myocyanophage communities corresponded with the larger distances between the sampling sites. Collectively, this study suggests that the newly designed primer pair can be effectively used to study the community and diversity of myocyanophage from different environments, and the high-throughput sequencing represents a good method to understand viral diversity.

  9. Meeting diversity in ergonomics

    NARCIS (Netherlands)

    Pikaar, R.N.; Koningsveld, E.A.P.; Settels, P.J.M.

    2007-01-01

    Key Features: Offers the conceptual tools for creating more adaptable ergonomic designs to meet the needs of diverse human populations, Unlock the strategic business value found in ergonomically safe and comfortable products, Learn from in-depth case studies how ergonomic intervention was

  10. Strain-Level Diversity of Secondary Metabolism in Streptomyces albus

    Science.gov (United States)

    Seipke, Ryan F.

    2015-01-01

    Streptomyces spp. are robust producers of medicinally-, industrially- and agriculturally-important small molecules. Increased resistance to antibacterial agents and the lack of new antibiotics in the pipeline have led to a renaissance in natural product discovery. This endeavor has benefited from inexpensive high quality DNA sequencing technology, which has generated more than 140 genome sequences for taxonomic type strains and environmental Streptomyces spp. isolates. Many of the sequenced streptomycetes belong to the same species. For instance, Streptomyces albus has been isolated from diverse environmental niches and seven strains have been sequenced, consequently this species has been sequenced more than any other streptomycete, allowing valuable analyses of strain-level diversity in secondary metabolism. Bioinformatics analyses identified a total of 48 unique biosynthetic gene clusters harboured by Streptomyces albus strains. Eighteen of these gene clusters specify the core secondary metabolome of the species. Fourteen of the gene clusters are contained by one or more strain and are considered auxiliary, while 16 of the gene clusters encode the production of putative strain-specific secondary metabolites. Analysis of Streptomyces albus strains suggests that each strain of a Streptomyces species likely harbours at least one strain-specific biosynthetic gene cluster. Importantly, this implies that deep sequencing of a species will not exhaust gene cluster diversity and will continue to yield novelty. PMID:25635820

  11. What is the relationship between diversity and performance? A study about the relationship between the proportion of people with disabilities in the productivity of Brazilian firms

    Directory of Open Access Journals (Sweden)

    Luciana Carvalho de Mesquita Ferreira

    2016-06-01

    Full Text Available Purpose – This study aims to analyze the relationship between greater participation of people with disabilities in Brazilian firms and productivity as a performance indicator. Design/methodology/approach – To test the relationship between the proportion of PwD and the productivity of Brazilian firms, we used regression analysis with panel data and a dataset of public information from 46 firms for years 2010 and 2011. Findings – There was no statistical evidence stating that a greater proportion of people with disabilities in the workforce has a negative (or positive relationship with the productivity of Brazilian firms. Conversely, a positive relationship between a greater proportion of people with disabilities and productivity was found amongst firms that present greater social commitment. Originality/value – These results indicate the contingent character associated with diversity management, and that the adoption of social practices by Brazilian firms can be an important mechanism for the management of diversity and inclusion.

  12. Long-range high-speed visible light communication system over 100-m outdoor transmission utilizing receiver diversity technology

    Science.gov (United States)

    Wang, Yiguang; Huang, Xingxing; Shi, Jianyang; Wang, Yuan-quan; Chi, Nan

    2016-05-01

    Visible light communication (VLC) has no doubt become a promising candidate for future wireless communications due to the increasing trends in the usage of light-emitting diodes (LEDs). In addition to indoor high-speed wireless access and positioning applications, VLC usage in outdoor scenarios, such as vehicle networks and intelligent transportation systems, are also attracting significant interest. However, the complex outdoor environment and ambient noise are the key challenges for long-range high-speed VLC outdoor applications. To improve system performance and transmission distance, we propose to use receiver diversity technology in an outdoor VLC system. Maximal ratio combining-based receiver diversity technology is utilized in two receivers to achieve the maximal signal-to-noise ratio. A 400-Mb/s VLC transmission using a phosphor-based white LED and a 1-Gb/s wavelength division multiplexing VLC transmission using a red-green-blue LED are both successfully achieved over a 100-m outdoor distance with the bit error rate below the 7% forward error correction limit of 3.8×10-3. To the best of our knowledge, this is the highest data rate at 100-m outdoor VLC transmission ever achieved. The experimental results clearly prove the benefit and feasibility of receiver diversity technology for long-range high-speed outdoor VLC systems.

  13. Genotypic and phenotypic diversity does not affect productivity and drought response in competitive stands of Trifolium repens

    Directory of Open Access Journals (Sweden)

    Heidrun eHuber

    2016-03-01

    Full Text Available Clonal plants can form dense canopies in which plants of different genetic origin are competing for the uptake of essential resources. The competitive relationships among these clones are likely to be affected by extreme environmental conditions, such as prolonged drought spells, which are predicted to occur more frequently due to global climate change. This, in turn, may alter characteristics of the ecological system and its associated functioning.We hypothesized that the relative success of individual clones will depend on the size of the ramets as ramets with larger leaves and longer petioles (large ramets were predicted to have a competitive advantage in terms of increased light interception over smaller-sized ramets. Under drier conditions the relative performances of genotypes were expected to change leading to a change in genotype ranking. We also hypothesized that increased genotypic and phenotypic diversity will increase stand performance and resistance to drought. These hypotheses and the mechanisms responsible for shifts in competitive relationships were investigated by subjecting genotypes of the important pasture legume Trifolium repens to competition with either genetically identical clones, genetically different but similarly sized clones, or genetically as well as morphologically different clones under well-watered and dry conditions.Competitive relationships were affected by ramet size with large genotypes outperforming small genotypes in diverse stands in terms of biomass production. However, large genotypes also produced relatively fewer ramets than small genotypes and could not benefit in terms of clonal reproduction from competing with smaller genotypes, indicating that evolutionary shifts in genotype composition will depend on whether ramet size or ramet number is under selection. In contrast to our hypotheses, diversity did not increase stand performance under different selection regimes and genotype ranking was hardly

  14. Genotypic and Phenotypic Diversity Does Not Affect Productivity and Drought Response in Competitive Stands of Trifolium repens.

    Science.gov (United States)

    Huber, Heidrun; During, Heinjo J; Bruine de Bruin, Fabienne; Vermeulen, Peter J; Anten, Niels P R

    2016-01-01

    Clonal plants can form dense canopies in which plants of different genetic origin are competing for the uptake of essential resources. The competitive relationships among these clones are likely to be affected by extreme environmental conditions, such as prolonged drought spells, which are predicted to occur more frequently due to global climate change. This, in turn, may alter characteristics of the ecological system and its associated functioning. We hypothesized that the relative success of individual clones will depend on the size of the ramets as ramets with larger leaves and longer petioles (large ramets) were predicted to have a competitive advantage in terms of increased light interception over smaller-sized ramets. Under drier conditions the relative performances of genotypes were expected to change leading to a change in genotype ranking. We also hypothesized that increased genotypic and phenotypic diversity will increase stand performance and resistance to drought. These hypotheses and the mechanisms responsible for shifts in competitive relationships were investigated by subjecting genotypes of the important pasture legume Trifolium repens to competition with either genetically identical clones, genetically different but similarly sized clones, or genetically as well as morphologically different clones under well-watered and dry conditions. Competitive relationships were affected by ramet size with large genotypes outperforming small genotypes in diverse stands in terms of biomass production. However, large genotypes also produced relatively fewer ramets than small genotypes and could not benefit in terms of clonal reproduction from competing with smaller genotypes, indicating that evolutionary shifts in genotype composition will depend on whether ramet size or ramet number is under selection. In contrast to our hypotheses, diversity did not increase stand performance under different selection regimes and genotype ranking was hardly affected by soil

  15. Strategies for achieving high sequencing accuracy for low diversity samples and avoiding sample bleeding using illumina platform.

    Science.gov (United States)

    Mitra, Abhishek; Skrzypczak, Magdalena; Ginalski, Krzysztof; Rowicka, Maga

    2015-01-01

    Sequencing microRNA, reduced representation sequencing, Hi-C technology and any method requiring the use of in-house barcodes result in sequencing libraries with low initial sequence diversity. Sequencing such data on the Illumina platform typically produces low quality data due to the limitations of the Illumina cluster calling algorithm. Moreover, even in the case of diverse samples, these limitations are causing substantial inaccuracies in multiplexed sample assignment (sample bleeding). Such inaccuracies are unacceptable in clinical applications, and in some other fields (e.g. detection of rare variants). Here, we discuss how both problems with quality of low-diversity samples and sample bleeding are caused by incorrect detection of clusters on the flowcell during initial sequencing cycles. We propose simple software modifications (Long Template Protocol) that overcome this problem. We present experimental results showing that our Long Template Protocol remarkably increases data quality for low diversity samples, as compared with the standard analysis protocol; it also substantially reduces sample bleeding for all samples. For comprehensiveness, we also discuss and compare experimental results from alternative approaches to sequencing low diversity samples. First, we discuss how the low diversity problem, if caused by barcodes, can be avoided altogether at the barcode design stage. Second and third, we present modified guidelines, which are more stringent than the manufacturer's, for mixing low diversity samples with diverse samples and lowering cluster density, which in our experience consistently produces high quality data from low diversity samples. Fourth and fifth, we present rescue strategies that can be applied when sequencing results in low quality data and when there is no more biological material available. In such cases, we propose that the flowcell be re-hybridized and sequenced again using our Long Template Protocol. Alternatively, we discuss how

  16. Strategies for achieving high sequencing accuracy for low diversity samples and avoiding sample bleeding using illumina platform.

    Directory of Open Access Journals (Sweden)

    Abhishek Mitra

    Full Text Available Sequencing microRNA, reduced representation sequencing, Hi-C technology and any method requiring the use of in-house barcodes result in sequencing libraries with low initial sequence diversity. Sequencing such data on the Illumina platform typically produces low quality data due to the limitations of the Illumina cluster calling algorithm. Moreover, even in the case of diverse samples, these limitations are causing substantial inaccuracies in multiplexed sample assignment (sample bleeding. Such inaccuracies are unacceptable in clinical applications, and in some other fields (e.g. detection of rare variants. Here, we discuss how both problems with quality of low-diversity samples and sample bleeding are caused by incorrect detection of clusters on the flowcell during initial sequencing cycles. We propose simple software modifications (Long Template Protocol that overcome this problem. We present experimental results showing that our Long Template Protocol remarkably increases data quality for low diversity samples, as compared with the standard analysis protocol; it also substantially reduces sample bleeding for all samples. For comprehensiveness, we also discuss and compare experimental results from alternative approaches to sequencing low diversity samples. First, we discuss how the low diversity problem, if caused by barcodes, can be avoided altogether at the barcode design stage. Second and third, we present modified guidelines, which are more stringent than the manufacturer's, for mixing low diversity samples with diverse samples and lowering cluster density, which in our experience consistently produces high quality data from low diversity samples. Fourth and fifth, we present rescue strategies that can be applied when sequencing results in low quality data and when there is no more biological material available. In such cases, we propose that the flowcell be re-hybridized and sequenced again using our Long Template Protocol. Alternatively

  17. Plant diversity and energy potency of community forest in East Kalimantan, Indonesia: Searching for fast growing wood species for energy production

    Directory of Open Access Journals (Sweden)

    RUDIANTO AMIRTA

    2016-05-01

    Full Text Available Abstract. Amirta R, Yuliansyah, Angi EM, Ananto BR, Setiyono B, Haqiqi MT, Septiana HA, Lodong M, Oktavianto RN. 2016. Plant diversity and energy potency of community forest in East Kalimantan, Indonesia: Searching for fast growing wood species for energy production. Nusantara Bioscience 8: 22-30. Nowadays, there is an increasing interest in intensifying the production and use of biomass to replace fossil fuels for the production of heat and electricity, especially for a remote area that generally abundance with the wood biomass resources including in East Kalimantan, Indonesia. In this work, diversity of plant species that commonly growth in community forest area of East Kutai District, East Kalimantan, Indonesia had been studied to point out their energy potency to be used as biomass feedstock for the electricity generated. Diversity of plant species in the community forest was evaluated by making 13 sampling plots with 20mx20m size approximately. Concurently, the energy properties of plant biomass such as proximate and ultimate compositions were also analyzed using ASTM methods. Results showed that more than 30 species of tropical trees and wood shrubs were grown in the community forest. The presence of them was classified into two different growth of origins: natural and artificial plantation, and also three different categories of plant resources: tree species from logged over forest, commercial fast growing plant tree species for the fiber production and woody shrubs. The highest dominancy and productivity was found in Paraserianthes falcataria (L. Nielsen since the wood biomass was artificially planted for the commercial purposes. Among the 31 plant species analyzed we found the highest energy potency was obtained from Cratoxylum cochinchinense (Lour. Blume that produced 3.17 MWh/ton, and the lowest was from Trema orientalis (L. Blume 0.97 MWh/ton. The woody shrubs species such as Vernonia amigdalina Delile., Piper aduncum L., Gliricidia

  18. Limited Bacterial Diversity within a Treatment Plant Receiving Antibiotic-Containing Waste from Bulk Drug Production

    Science.gov (United States)

    Shouche, Yogesh S.; Larsson, D. G. Joakim

    2016-01-01

    Biological treatment of waste water from bulk drug production, contaminated with high levels of fluoroquinolone antibiotics, can lead to massive enrichment of antibiotic resistant bacteria, resistance genes and associated mobile elements, as previously shown. Such strong selection may be boosted by the use of activated sludge (AS) technology, where microbes that are able to thrive on the chemicals within the wastewater are reintroduced at an earlier stage of the process to further enhance degradation of incoming chemicals. The microbial community structure within such a treatment plant is, however, largely unclear. In this study, Illumina-based 16S rRNA amplicon sequencing was applied to investigate the bacterial communities of different stages from an Indian treatment plant operated by Patancheru Environment Technology Limited (PETL) in Hyderabad, India. The plant receives waste water with high levels of fluoroquinolones and applies AS technology. A total of 1,019,400 sequences from samples of different stages of the treatment process were analyzed. In total 202, 303, 732, 652, 947 and 864 operational taxonomic units (OTUs) were obtained at 3% distance cutoff in the equilibrator, aeration tanks 1 and 2, settling tank, secondary sludge and old sludge samples from PETL, respectively. Proteobacteria was the most dominant phyla in all samples with Gammaproteobacteria and Betaproteobacteria being the dominant classes. Alcaligenaceae and Pseudomonadaceae, bacterial families from PETL previously reported to be highly multidrug resistant, were the dominant families in aeration tank samples. Despite regular addition of human sewage (approximately 20%) to uphold microbial activity, the bacterial diversity within aeration tanks from PETL was considerably lower than corresponding samples from seven, regular municipal waste water treatment plants. The strong selection pressure from antibiotics present may be one important factor in structuring the microbial community in PETL

  19. Limited Bacterial Diversity within a Treatment Plant Receiving Antibiotic-Containing Waste from Bulk Drug Production.

    Science.gov (United States)

    Marathe, Nachiket P; Shetty, Sudarshan A; Shouche, Yogesh S; Larsson, D G Joakim

    2016-01-01

    Biological treatment of waste water from bulk drug production, contaminated with high levels of fluoroquinolone antibiotics, can lead to massive enrichment of antibiotic resistant bacteria, resistance genes and associated mobile elements, as previously shown. Such strong selection may be boosted by the use of activated sludge (AS) technology, where microbes that are able to thrive on the chemicals within the wastewater are reintroduced at an earlier stage of the process to further enhance degradation of incoming chemicals. The microbial community structure within such a treatment plant is, however, largely unclear. In this study, Illumina-based 16S rRNA amplicon sequencing was applied to investigate the bacterial communities of different stages from an Indian treatment plant operated by Patancheru Environment Technology Limited (PETL) in Hyderabad, India. The plant receives waste water with high levels of fluoroquinolones and applies AS technology. A total of 1,019,400 sequences from samples of different stages of the treatment process were analyzed. In total 202, 303, 732, 652, 947 and 864 operational taxonomic units (OTUs) were obtained at 3% distance cutoff in the equilibrator, aeration tanks 1 and 2, settling tank, secondary sludge and old sludge samples from PETL, respectively. Proteobacteria was the most dominant phyla in all samples with Gammaproteobacteria and Betaproteobacteria being the dominant classes. Alcaligenaceae and Pseudomonadaceae, bacterial families from PETL previously reported to be highly multidrug resistant, were the dominant families in aeration tank samples. Despite regular addition of human sewage (approximately 20%) to uphold microbial activity, the bacterial diversity within aeration tanks from PETL was considerably lower than corresponding samples from seven, regular municipal waste water treatment plants. The strong selection pressure from antibiotics present may be one important factor in structuring the microbial community in PETL

  20. Limited Bacterial Diversity within a Treatment Plant Receiving Antibiotic-Containing Waste from Bulk Drug Production.

    Directory of Open Access Journals (Sweden)

    Nachiket P Marathe

    Full Text Available Biological treatment of waste water from bulk drug production, contaminated with high levels of fluoroquinolone antibiotics, can lead to massive enrichment of antibiotic resistant bacteria, resistance genes and associated mobile elements, as previously shown. Such strong selection may be boosted by the use of activated sludge (AS technology, where microbes that are able to thrive on the chemicals within the wastewater are reintroduced at an earlier stage of the process to further enhance degradation of incoming chemicals. The microbial community structure within such a treatment plant is, however, largely unclear. In this study, Illumina-based 16S rRNA amplicon sequencing was applied to investigate the bacterial communities of different stages from an Indian treatment plant operated by Patancheru Environment Technology Limited (PETL in Hyderabad, India. The plant receives waste water with high levels of fluoroquinolones and applies AS technology. A total of 1,019,400 sequences from samples of different stages of the treatment process were analyzed. In total 202, 303, 732, 652, 947 and 864 operational taxonomic units (OTUs were obtained at 3% distance cutoff in the equilibrator, aeration tanks 1 and 2, settling tank, secondary sludge and old sludge samples from PETL, respectively. Proteobacteria was the most dominant phyla in all samples with Gammaproteobacteria and Betaproteobacteria being the dominant classes. Alcaligenaceae and Pseudomonadaceae, bacterial families from PETL previously reported to be highly multidrug resistant, were the dominant families in aeration tank samples. Despite regular addition of human sewage (approximately 20% to uphold microbial activity, the bacterial diversity within aeration tanks from PETL was considerably lower than corresponding samples from seven, regular municipal waste water treatment plants. The strong selection pressure from antibiotics present may be one important factor in structuring the microbial

  1. Active Seattle: achieving walkability in diverse neighborhoods.

    Science.gov (United States)

    Deehr, Rebecca C; Shumann, Amy

    2009-12-01

    The Active Living by Design project based in Seattle (Active Seattle) advocated for policies and projects in diverse communities supporting a more walkable city, while using social marketing and education to get more people walking more often. Walking audits were carried out in select diverse neighborhoods, resulting in recommendations for policy change and built-environment improvements. Advocacy for city-scale policies also occurred. Walking maps and other social-marketing products promoted behavior change. Major Safe Routes to School activities occurred and were made possible by separate funding sources. Positive results of Active Seattle included an increase in funding for pedestrian infrastructure, a pedestrian master plan, a Complete Streets policy, substantial increase in Safe Routes to School activity, and institutionalization of active living and active transportation within partner agencies. Challenges included institutional prioritization for improving pedestrian infrastructure, funding inequity, and a community need that was greater than could be fulfilled. Efforts to overcome funding inequities or other resistance to pedestrian-oriented physical projects will benefit from high-visibility campaigns that have a lasting impact on public perception and decision makers' political will. To reach vulnerable populations that have substantial barriers to increasing walking frequency, extensive staff time for outreach is needed. Changing the built environment to encourage walking may be a long-term solution in communities with diverse populations. Influencing and educating local government officials to make active living projects and policies a high budgetary priority is essential for large-scale impact and long-term change.

  2. How important is diversity for capturing environmental-change responses in ecosystem models?

    DEFF Research Database (Denmark)

    Prowe, Friederike; Pahlow, M.; Dutkiewicz, S.

    2014-01-01

    Marine ecosystem models used to investigate how global change affects ocean ecosystems and their functioning typically omit pelagic plankton diversity. Diversity, however, may affect functions such as primary production and their sensitivity to environmental changes. Here we use a global ocean...... ecosystem model that explicitly resolves phytoplankton diversity by defining subtypes within four phytoplankton functional types (PFTs). We investigate the model's ability to capture diversity effects on primary production under environmental change. An idealized scenario with a sudden reduction in vertical...... in the model, for example via trade-offs or different PFTs, thus determines the diversity effects on ecosystem functioning captured in ocean ecosystem models....

  3. Patterns of tree species diversity in relation to climatic factors on the Sierra Madre Occidental, Mexico.

    Science.gov (United States)

    Silva-Flores, Ramón; Pérez-Verdín, Gustavo; Wehenkel, Christian

    2014-01-01

    Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole), 54 species of Quercus (ca. 9-14%), 7 species of Arbutus (ca. 50%) and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally higher in cold

  4. Patterns of Tree Species Diversity in Relation to Climatic Factors on the Sierra Madre Occidental, Mexico

    Science.gov (United States)

    Silva-Flores, Ramón; Pérez-Verdín, Gustavo; Wehenkel, Christian

    2014-01-01

    Biological diversity can be defined as variability among living organisms from all sources, including terrestrial organisms, marine and other aquatic ecosystems, and the ecological complexes which they are part of. This includes diversity within species, between species, and of ecosystems. Numerous diversity indices combine richness and evenness in a single expression, and several climate-based explanations have been proposed to explain broad-scale diversity patterns. However, climate-based water-energy dynamics appears to be an essential factor that determines patterns of diversity. The Mexican Sierra Madre Occidental occupies an area of about 29 million hectares and is located between the Neotropical and Holarctic ecozones. It shelters a high diversity of flora, including 24 different species of Pinus (ca. 22% on the whole), 54 species of Quercus (ca. 9–14%), 7 species of Arbutus (ca. 50%) and many other trees species. The objectives of this study were to model how tree species diversity is related to climatic and geographic factors and stand density and to test the Metabolic Theory, Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis, Mid-Domain Effect, and the Water-Energy Dynamic Theory on the Sierra Madre Occidental, Durango. The results supported the Productivity-Diversity Hypothesis, Physiological Tolerance Hypothesis and Water-Energy Dynamic Theory, but not the Mid-Domain Effect or Metabolic Theory. The annual aridity index was the variable most closely related to the diversity indices analyzed. Contemporary climate was found to have moderate to strong effects on the minimum, median and maximum tree species diversity. Because water-energy dynamics provided a satisfactory explanation for the patterns of minimum, median and maximum diversity, an understanding of this factor is critical to future biodiversity research. Quantile regression of the data showed that the three diversity parameters of tree species are generally higher in cold

  5. Salmonella enterica Prophage Sequence Profiles Reflect Genome Diversity and Can Be Used for High Discrimination Subtyping

    Directory of Open Access Journals (Sweden)

    Walid Mottawea

    2018-05-01

    Full Text Available Non-typhoidal Salmonella is a leading cause of foodborne illness worldwide. Prompt and accurate identification of the sources of Salmonella responsible for disease outbreaks is crucial to minimize infections and eliminate ongoing sources of contamination. Current subtyping tools including single nucleotide polymorphism (SNP typing may be inadequate, in some instances, to provide the required discrimination among epidemiologically unrelated Salmonella strains. Prophage genes represent the majority of the accessory genes in bacteria genomes and have potential to be used as high discrimination markers in Salmonella. In this study, the prophage sequence diversity in different Salmonella serovars and genetically related strains was investigated. Using whole genome sequences of 1,760 isolates of S. enterica representing 151 Salmonella serovars and 66 closely related bacteria, prophage sequences were identified from assembled contigs using PHASTER. We detected 154 different prophages in S. enterica genomes. Prophage sequences were highly variable among S. enterica serovars with a median ± interquartile range (IQR of 5 ± 3 prophage regions per genome. While some prophage sequences were highly conserved among the strains of specific serovars, few regions were lineage specific. Therefore, strains belonging to each serovar could be clustered separately based on their prophage content. Analysis of S. Enteritidis isolates from seven outbreaks generated distinct prophage profiles for each outbreak. Taken altogether, the diversity of the prophage sequences correlates with genome diversity. Prophage repertoires provide an additional marker for differentiating S. enterica subtypes during foodborne outbreaks.

  6. Multi-stage high cell continuous fermentation for high productivity and titer.

    Science.gov (United States)

    Chang, Ho Nam; Kim, Nag-Jong; Kang, Jongwon; Jeong, Chang Moon; Choi, Jin-dal-rae; Fei, Qiang; Kim, Byoung Jin; Kwon, Sunhoon; Lee, Sang Yup; Kim, Jungbae

    2011-05-01

    We carried out the first simulation on multi-stage continuous high cell density culture (MSC-HCDC) to show that the MSC-HCDC can achieve batch/fed-batch product titer with much higher productivity to the fed-batch productivity using published fermentation kinetics of lactic acid, penicillin and ethanol. The system under consideration consists of n-serially connected continuous stirred-tank reactors (CSTRs) with either hollow fiber cell recycling or cell immobilization for high cell-density culture. In each CSTR substrate supply and product removal are possible. Penicillin production is severely limited by glucose metabolite repression that requires multi-CSTR glucose feeding. An 8-stage C-HCDC lactic acid fermentation resulted in 212.9 g/L of titer and 10.6 g/L/h of productivity, corresponding to 101 and 429% of the comparable lactic acid fed-batch, respectively. The penicillin production model predicted 149% (0.085 g/L/h) of productivity in 8-stage C-HCDC with 40 g/L of cell density and 289% of productivity (0.165 g/L/h) in 7-stage C-HCDC with 60 g/L of cell density compared with referring batch cultivations. A 2-stage C-HCDC ethanol experimental run showed 107% titer and 257% productivity of the batch system having 88.8 g/L of titer and 3.7 g/L/h of productivity. MSC-HCDC can give much higher productivity than batch/fed-batch system, and yield a several percentage higher titer as well. The productivity ratio of MSC-HCDC over batch/fed-batch system is given as a multiplication of system dilution rate of MSC-HCDC and cycle time of batch/fed-batch system. We suggest MSC-HCDC as a new production platform for various fermentation products including monoclonal antibody.

  7. Discovering Diversity in Marketing Practice

    OpenAIRE

    Murray, John; O'Driscoll, Aidan; Torres, Ann

    2002-01-01

    Marketing practice varies among firms. However, the prescriptive literature emphasises a universal view of practice, a “one-size-fits-all” view. This paper addresses the issue of explaining diversity in competitive space and over time. Diversity in competitive space reflects the existence of different routes to high performance. Diversity over time reflects some combination of change in the individual firm and change in a population of firms. In the former case, diversity is shaped by organis...

  8. Forbs enhance productivity of unfertilised grass-clover leys and support low-carbon bioenergy

    DEFF Research Database (Denmark)

    Cong, Wen-Feng; Jing, Jingying; Rasmussen, Jim

    2017-01-01

    Intensively managed grasslands are dominated by highly productive grass-clover mixtures. Increasing crop diversity by inclusion of competitive forbs may enhance biomass production and sustainable biofuel production. Here we examined if one or all of three forbs (chicory, Cichorium intybus L.; car...

  9. Large-scale diversity of slope fishes: pattern inconsistency between multiple diversity indices.

    Science.gov (United States)

    Gaertner, Jean-Claude; Maiorano, Porzia; Mérigot, Bastien; Colloca, Francesco; Politou, Chrissi-Yianna; Gil De Sola, Luis; Bertrand, Jacques A; Murenu, Matteo; Durbec, Jean-Pierre; Kallianiotis, Argyris; Mannini, Alessandro

    2013-01-01

    Large-scale studies focused on the diversity of continental slope ecosystems are still rare, usually restricted to a limited number of diversity indices and mainly based on the empirical comparison of heterogeneous local data sets. In contrast, we investigate large-scale fish diversity on the basis of multiple diversity indices and using 1454 standardized trawl hauls collected throughout the upper and middle slope of the whole northern Mediterranean Sea (36°3'- 45°7' N; 5°3'W - 28°E). We have analyzed (1) the empirical relationships between a set of 11 diversity indices in order to assess their degree of complementarity/redundancy and (2) the consistency of spatial patterns exhibited by each of the complementary groups of indices. Regarding species richness, our results contrasted both the traditional view based on the hump-shaped theory for bathymetric pattern and the commonly-admitted hypothesis of a large-scale decreasing trend correlated with a similar gradient of primary production in the Mediterranean Sea. More generally, we found that the components of slope fish diversity we analyzed did not always show a consistent pattern of distribution according either to depth or to spatial areas, suggesting that they are not driven by the same factors. These results, which stress the need to extend the number of indices traditionally considered in diversity monitoring networks, could provide a basis for rethinking not only the methodological approach used in monitoring systems, but also the definition of priority zones for protection. Finally, our results call into question the feasibility of properly investigating large-scale diversity patterns using a widespread approach in ecology, which is based on the compilation of pre-existing heterogeneous and disparate data sets, in particular when focusing on indices that are very sensitive to sampling design standardization, such as species richness.

  10. Networking for Successful Diversity Recruiting: Creating a Highly Diverse Research Experiences for Undergraduates Program by Networking with Mentors, Faculty, and Students.

    Science.gov (United States)

    Dalbotten, D. M.; Berthelote, A.; Watts, N. B.

    2017-12-01

    Successfully recruiting for diversity begins as you plan your program and make sure that all elements of the program support diverse participation. The REU on Sustainable Land and Water Resources continues to be one of the most diverse NSF-funded Research Experience for Undergraduate Programs in the geosciences. Every aspect of the program, from recruiting, the application process, selecting participants, and the methods developed to support participant success have been scrutinized and tailored towards broadening participation. While the focus of the research has been on collaboration with Native American reservations to create community-based participatory research projects and improving access for Native American students, the PIs strive for ethnic and cultural diversity of the participants. Emphasis on networking and building relationships with minority-serving institutions has led to increasing numbers of underrepresented students applying to the REU. In 2017, a full 30% of our applications were from underrepresented groups. The authors will discuss methods for improved diversity recruiting, as well as ways to make every aspect of your program support diversity in the geosciences.

  11. Food variety, dietary diversity and perceived hunger among lactating ...

    African Journals Online (AJOL)

    Food variety, dietary diversity and perceived hunger among lactating women (0-6 ... Vitamin A rich vegetables/fruits (6.6%) and dairy products (1.7%) had the ... from culturally acceptable and affordable foods to increase dietary diversity of ...

  12. High abundance and diversity of consumers associated with eutrophic areas in a semi-desert macrotidal coastal ecosystem in Patagonia, Argentina

    Science.gov (United States)

    Martinetto, Paulina; Daleo, Pedro; Escapa, Mauricio; Alberti, Juan; Isacch, Juan Pablo; Fanjul, Eugenia; Botto, Florencia; Piriz, Maria Luz; Ponce, Gabriela; Casas, Graciela; Iribarne, Oscar

    2010-07-01

    Here we evaluated the response to eutrophication in terms of abundance and diversity of flora and fauna in a semi-desert macrotidal coastal system (San Antonio bay, Patagonia, Argentina, 40° 48' S) where signs of eutrophication (high nutrient concentration, seaweed blooms, high growth rate of macroalgae) have been reported. We compared abundances and species composition of macroalgae, small infaunal and epifaunal invertebrates, and birds associated with tidal channels of the San Antonio Bay subject to contrasting anthropogenic influence. Macroalgae were more abundant and diverse in the channel closer to human activity where nutrient concentrations were also higher. In contrast to what others have observed in eutrophic sites, small invertebrates and birds were also more abundant and diverse in the channel with macroalgal blooms and high nutrient concentration. The large water flushing during the tidal cycle could prevent anoxic or hypoxic events, making the environment suitable for consumers. Thus, this could be a case in which eutrophication supports high densities of consumers by increasing food availability, rather than negatively affecting the survival of organisms.

  13. High throughput protein production screening

    Science.gov (United States)

    Beernink, Peter T [Walnut Creek, CA; Coleman, Matthew A [Oakland, CA; Segelke, Brent W [San Ramon, CA

    2009-09-08

    Methods, compositions, and kits for the cell-free production and analysis of proteins are provided. The invention allows for the production of proteins from prokaryotic sequences or eukaryotic sequences, including human cDNAs using PCR and IVT methods and detecting the proteins through fluorescence or immunoblot techniques. This invention can be used to identify optimized PCR and WT conditions, codon usages and mutations. The methods are readily automated and can be used for high throughput analysis of protein expression levels, interactions, and functional states.

  14. Above- and below-ground effects of plant diversity depend on species origin

    DEFF Research Database (Denmark)

    Kuebbing, Sara E.; Classen, Aimee Taylor; Sanders, Nate

    2015-01-01

    -interaction models to describe how species' interactions influenced diversity-productivity relationships. Communities with more species had higher total biomass than did monoculture communities, but native and nonnative communities diverged in root : shoot ratios and the mechanism responsible for increased......Although many plant communities are invaded by multiple nonnative species, we have limited information on how a species' origin affects ecosystem function. We tested how differences in species richness and origin affect productivity and seedling establishment. We created phylogenetically paired...... native and nonnative plant communities in a glasshouse experiment to test diversity-productivity relationships and responsible mechanisms (i.e. selection or complementarity effects). Additionally, we tested how productivity and associated mechanisms influenced seedling establishment. We used diversity...

  15. CUSTOMER SERVICES AND PRODUCT QUALITY

    Directory of Open Access Journals (Sweden)

    NEAMŢU Liviu

    2013-04-01

    Full Text Available Objective level of product is a combination of material elements. They are supplemented by satisfying highly heterogeneous and complex motivations, representing highly diverse subjective functions associated to product until individualization for each type of consumption. Thus it observes highly surprising developments of subjective function associated with a product and which determines in the consumer's opinion the quality level of the product. The present study examines the role of associated services covering the subjective function of the product in view of the fact that the utility or subjective function is dependent on elements such as style, fashion and fads. Consumers will no longer accept products with average quality of related services. For a company that wants to stay in the market and achieve profitability, the only solution is moving towards a complete product package type goods-services. Associated services are thus an indicator of quality and the best customer loyalty insurance policy, there is a close relationship between the quality of services provided by a firm, customer satisfaction and company profitability.

  16. Estimating tree species diversity in the savannah using NDVI and woody canopy cover

    Science.gov (United States)

    Madonsela, Sabelo; Cho, Moses Azong; Ramoelo, Abel; Mutanga, Onisimo; Naidoo, Laven

    2018-04-01

    Remote sensing applications in biodiversity research often rely on the establishment of relationships between spectral information from the image and tree species diversity measured in the field. Most studies have used normalized difference vegetation index (NDVI) to estimate tree species diversity on the basis that it is sensitive to primary productivity which defines spatial variation in plant diversity. The NDVI signal is influenced by photosynthetically active vegetation which, in the savannah, includes woody canopy foliage and grasses. The question is whether the relationship between NDVI and tree species diversity in the savanna depends on the woody cover percentage. This study explored the relationship between woody canopy cover (WCC) and tree species diversity in the savannah woodland of southern Africa and also investigated whether there is a significant interaction between seasonal NDVI and WCC in the factorial model when estimating tree species diversity. To fulfil our aim, we followed stratified random sampling approach and surveyed tree species in 68 plots of 90 m × 90 m across the study area. Within each plot, all trees with diameter at breast height of >10 cm were sampled and Shannon index - a common measure of species diversity which considers both species richness and abundance - was used to quantify tree species diversity. We then extracted WCC in each plot from existing fractional woody cover product produced from Synthetic Aperture Radar (SAR) data. Factorial regression model was used to determine the interaction effect between NDVI and WCC when estimating tree species diversity. Results from regression analysis showed that (i) WCC has a highly significant relationship with tree species diversity (r2 = 0.21; p NDVI and WCC is not significant, however, the factorial model significantly reduced the error of prediction (RMSE = 0.47, p NDVI (RMSE = 0.49) or WCC (RMSE = 0.49) model during the senescence period. The result justifies our assertion

  17. An ecological paradox: high species diversity and low position of the upper forest line in the Andean Depression.

    Science.gov (United States)

    Peters, Thorsten; Braeuning, Achim; Muenchow, Jannes; Richter, Michael

    2014-06-01

    Systematic investigations of the upper forest line (UFL) primarily concentrate on mid and high latitudes of the Northern Hemisphere, whereas studies of Neotropical UFLs are still fragmentary. This article outlines the extraordinary high tree diversity at the UFL within the Andean Depression and unravels the links between the comparatively low position of the local UFL, high tree-species diversity, and climate. On the basis of Gentry's rapid inventory methodology for the tropics, vegetation sampling was conducted at 12 UFL sites, and local climate (temperature, wind, precipitation, and soil moisture) was investigated at six sites. Monotypic forests dominated by Polylepis were only found at the higher located margins of the Andean Depression while the lower situated core areas were characterized by a species-rich forest, which lacked the elsewhere dominant tree-species Polylepis. In total, a remarkably high tree-species number of 255 tree species of 40 different plant families was found. Beta-diversity was also high with more than two complete species turnovers. A non-linear relationship between the floristic similarity of the investigated study sites and elevation was detected. Temperatures at the investigated study sites clearly exceeded 5.5°C, the postulated threshold value for the upper tree growth limit in the tropics. Instead, quasi-permanent trade winds, high precipitation amounts, and high soil water contents affect the local position of the UFL in a negative way. Interestingly, most of the above-mentioned factors are also contributing to the high species richness. The result is a combination of a clearly marked upper forest line depression combined with an extraordinary forest line complexity, which was an almost unknown paradox.

  18. Ecological partitioning and diversity in tropical planktonic foraminifera

    Directory of Open Access Journals (Sweden)

    Seears Heidi A

    2012-04-01

    Full Text Available Abstract Background Ecological processes are increasingly being viewed as an important mode of diversification in the marine environment, where the high dispersal potential of pelagic organisms, and a lack of absolute barriers to gene flow may limit the occurrence of allopatric speciation through vicariance. Here we focus on the potential role of ecological partitioning in the diversification of a widely distributed group of marine protists, the planktonic foraminifera. Sampling was conducted in the tropical Arabian Sea, during the southwest (summer monsoon, when pronounced environmental conditions result in a strong disparity in temperature, salinity and productivity between distinct northern and southern water masses. Results We uncovered extensive genetic diversity within the Arabian Sea planktonic foraminifera, identifying 13 morphospecies, represented by 20 distinct SSU rRNA genetic types. Several morphospecies/genetic types displayed non-random biogeographical distributions, partitioning between the northern and southern water masses, giving a strong indication of independent ecological adaptations. Conclusions We propose sea-surface primary productivity as the main factor driving the geographical segregation of Arabian Sea planktonic foraminifera, during the SW monsoon, with variations in symbiotic associations possibly playing a role in the specific ecological adaptations observed. Our findings suggest that ecological partitioning could be contributing to the high levels of 'cryptic' genetic diversity observed within the planktonic foraminifera, and support the view that ecological processes may play a key role in the diversification of marine pelagic organisms.

  19. Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea)

    KAUST Repository

    Amer, Ranya A.

    2015-02-01

    Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt). Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed.

  20. Characterization of the diversity of mycosporine-like amino acids in lichens from high altitude region of Himalaya.

    Science.gov (United States)

    Shukla, Vertika; Kumari, Rupender; Patel, Davendra K; Upreti, Dalip K

    2016-01-01

    Lichens are tolerant to a number of environmental variables including high-intensity solar radiations, which is mainly due to the presence of chemical substances in the thallus. Especially, cyanobacterial lichens synthesize a unique class of chemical substances known as mycosporine-like amino acids (MAAs) the primary characteristic of which is strong ultraviolet (UV) absorption between 300 and 360 nm. In view of its UV-protecting potential, the applicability of mass spectral fragmentation using electrospray ionization tandem mass spectrometric analysis for the characterization of MAAs in lichen samples was explored. MAA compounds were characterized in four cyanobacteria-containing lichen species belonging to genus Peltigera, Stereocaulon and Lobaria. Among them, Peltigera and Lobaria are true cyanobacteria containing lichens (cyanolichens) while Stereocaulon is a tripartite lichen, as it contains both green algae (in the thallus) and cyanobacteria (in the cephalodia), collected from higher altitudes of Himalaya (Tungnath-Chopta in Garhwal Himalaya, 3432 m) from an exposed locality experiencing high light intensity. Mass spectral data of distinctive fragmentation pattern revealed that all the four species have good diversity of MAA compounds, especially Lobaria retigera was found to be enriched with highest diversity of oxo and imino MAAs. Overall, different numbers of oxo and imino MAA compounds were detected in the remaining lichen species. Good diversity of imino MAAs has ecological significance which is required to be investigated further. Moreover, the impressive diversity characterized in each lichen species suggests that lichens should be thoroughly studied for their MAAs contents.

  1. Historical and biological determinants of genetic diversity in the highly endemic triploid sea lavender Limonium dufourii (Plumbaginaceae).

    Science.gov (United States)

    Palop-Esteban, M; Segarra-Moragues, J G; González-Candelas, F

    2007-09-01

    Microsatellite markers were used to evaluate the genetic diversity and population genetic structure in the critically endangered Limonium dufourii (Plumbaginaceae), a highly endemic triploid species from the coasts of eastern Spain. Sixty-five alleles from 13 microsatellite regions were amplified in a sample of 122 individuals collected from the six extant populations. Microsatellite patterns were consistent with the triploid nature of L. dufourii. Alleles were unambiguously assigned to two different parental subgenomes in this hybrid species and the greater contribution of the diploid parental subgenome was confirmed. Eleven, 25 and 26 multilocus genotypes were recorded from the haploid, diploid and from the combined information of both subgenomes, respectively. Genetic diversity was mostly distributed among populations (72.06% of the total genetic variation). Genotypes from Marjal del Moro populations grouped into two highly structured clusters (88.41% of the total variance). The observed patterns of distribution of genetic diversity are interpreted to result from multiple hybridization events and isolation between populations. Threats to this species are mainly anthropogenic (urbanization and tourism pressure), although stochastic risks cannot be ignored. Therefore, in order to preserve extant genetic variation of L. dufourii, in situ strategies such as the preservation of its habitat are a high priority. Several recommendations in order to assist ex situ measures to guarantee the success of conservation strategies and maintain the relationships between individuals and populations are proposed.

  2. Beyond the Coral Triangle: high genetic diversity and near panmixia in Singapore's populations of the broadcast spawning sea star Protoreaster nodosus.

    Science.gov (United States)

    Tay, Y C; Chng, M W P; Sew, W W G; Rheindt, F E; Tun, K P P; Meier, R

    2016-08-01

    The Coral Triangle is widely considered the most important centre of marine biodiversity in Asia while areas on its periphery such as the South China Sea, have received much less interest. Here, we demonstrate that a small population of the knobbly sea star Protoreaster nodosus in Singapore has similarly high levels of genetic diversity as comparable Indonesian populations from the Coral Triangle. The high genetic diversity of this population is remarkable because it is maintained despite decades of continued anthropogenic disturbance. We postulate that it is probably due to broadcast spawning which is likely to maintain high levels of population connectivity. To test this, we analysed 6140 genome-wide single nucleotide polymorphism (SNP) loci for Singapore's populations and demonstrate a pattern of near panmixia. We here document a second case of high genetic diversity and low genetic structure for a broadcast spawner in Singapore, which suggests that such species have high resilience against anthropogenic disturbances. The study demonstrates the feasibility and power of using genome-wide SNPs for connectivity studies of marine invertebrates without a sequenced genome.

  3. Epigenetic diversity increases the productivity and stability of plant populations

    Czech Academy of Sciences Publication Activity Database

    Latzel, Vít; Allan, E.; Bortolini Silveira, A.; Colot, V.; Fischer, M.; Bossdorf, O.

    2013-01-01

    Roč. 4, Nov 2013 (2013), s. 1-7, č. 2875 ISSN 2041-1723 Institutional support: RVO:67985939 Keywords : Arabidopsis thaliana * ecosystem * diversity Subject RIV: EF - Botanics Impact factor: 10.742, year: 2013

  4. HIV populations are large and accumulate high genetic diversity in a nonlinear fashion.

    Science.gov (United States)

    Maldarelli, Frank; Kearney, Mary; Palmer, Sarah; Stephens, Robert; Mican, JoAnn; Polis, Michael A; Davey, Richard T; Kovacs, Joseph; Shao, Wei; Rock-Kress, Diane; Metcalf, Julia A; Rehm, Catherine; Greer, Sarah E; Lucey, Daniel L; Danley, Kristen; Alter, Harvey; Mellors, John W; Coffin, John M

    2013-09-01

    HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIV pro-pol to assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n = 22) or multiple, longitudinal (n = 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift.

  5. Analysing and Navigating Natural Products Space for Generating Small, Diverse, But Representative Chemical Libraries.

    Science.gov (United States)

    O'Hagan, Steve; Kell, Douglas B

    2018-01-01

    Armed with the digital availability of two natural products libraries, amounting to some 195 885 molecular entities, we ask the question of how we can best sample from them to maximize their "representativeness" in smaller and more usable libraries of 96, 384, 1152, and 1920 molecules. The term "representativeness" is intended to include diversity, but for numerical reasons (and the likelihood of being able to perform a QSAR) it is necessary to focus on areas of chemical space that are more highly populated. Encoding chemical structures as fingerprints using the RDKit "patterned" algorithm, we first assess the granularity of the natural products space using a simple clustering algorithm, showing that there are major regions of "denseness" but also a great many very sparsely populated areas. We then apply a "hybrid" hierarchical K-means clustering algorithm to the data to produce more statistically robust clusters from which representative and appropriate numbers of samples may be chosen. There is necessarily again a trade-off between cluster size and cluster number, but within these constraints, libraries containing 384 or 1152 molecules can be found that come from clusters that represent some 18 and 30% of the whole chemical space, with cluster sizes of, respectively, 50 and 27 or above, just about sufficient to perform a QSAR. By using the online availability of molecules via the Molport system (www.molport.com), we are also able to construct (and, for the first time, provide the contents of) a small virtual library of available molecules that provided effective coverage of the chemical space described. Consistent with this, the average molecular similarities of the contents of the libraries developed is considerably smaller than is that of the original libraries. The suggested libraries may have use in molecular or phenotypic screening, including for determining possible transporter substrates. © 2017 The Authors. Biotechnology Journal Published by Wiley

  6. "Legal highs" on the net-Evaluation of UK-based Websites, products and product information.

    Science.gov (United States)

    Schmidt, Martin M; Sharma, Akhilesh; Schifano, Fabrizio; Feinmann, Charlotte

    2011-03-20

    A vast array of substances are marketed as "legal highs" in the UK. These products are mainly marketed online and are packaged and produced to mimic illicit drugs. Little is known about the full range of products available at present and no studies have evaluated the product information provided to consumers. AIMS & HYPOTHESIS: To describe the available legal high products marketed by UK-based Internet retailers and evaluate the product information provided to consumers. Websites were identified using the terms "buy legal highs+UK" and two search engines. The first 100 hits and a random sample of 5% of the remaining results were screened. Websites based in the UK were included and all products were entered on a database. Information on product name, list price, claimed effects, side effects, contraindications and interactions was extracted. A descriptive analysis was conducted using SPSS v14. 115 Websites met the inclusion criteria but due to duplicate listings this was reduced to 39 unique Websites. 1308 products were found and evaluated. The average product price was 9.69 British pounds. Products took the form of pills (46.6%), smoking material (29.7%) and single plant material/extract (18.1%). Most products claimed to be stimulants (41.7%), sedatives (32.3%), or hallucinogens (12.9%). 40.1% of products failed to list ingredients, 91.9% failed to list side effects, 81.9% failed to list contraindications and 86.3% failed to list drug interactions. Top 5 products (with active ingredients in brackets) by frequency were Salvia divinorum (Salivinorin A), Kratom (Mitragynine), Hawaiian Baby Woodrose Seeds (Lysergic Acid Amide), Fly Agaric (Ibotenic Acid, Muscimol) and Genie (JWH018, CP47497). Products marketed as "legal highs" are easily available from UK-based Internet retailers and are reasonably affordable. Safety information provided to consumers is poor. Uninformed users risk serious adverse effects. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  7. Creative work environments in sport organizations: the influence of sexual orientation diversity and commitment to diversity.

    Science.gov (United States)

    Cunningham, George B

    2011-01-01

    Drawing from creative capital theory, the purpose of this study was to examine the degree to which sexual orientation diversity and commitment to diversity were predictive of workplaces that fostered creativity. Data were collected from 653 senior level athletic administrators and aggregated to the athletic department level of analysis (n = 199). Moderated regression indicated that sexual orientation diversity did not influence the presence of a creative work environment. There was however, a significant sexual orientation diversity × commitment to diversity interaction. When commitment to diversity was high, there was a positive association between sexual orientation diversity and a creative work environment; on the other hand, when commitment to diversity was low, the aforementioned relationship was negative. Results provide support for the notion that all diversity forms can be a source of enrichment and understanding, thereby benefiting the workplace.

  8. Local Plant Diversity Across Multiple Habitats Supports a Diverse Wild Bee Community in Pennsylvania Apple Orchards.

    Science.gov (United States)

    Kammerer, Melanie A; Biddinger, David J; Rajotte, Edwin G; Mortensen, David A

    2016-02-01

    Wild pollinators supply essential, historically undervalued pollination services to crops and other flowering plant communities with great potential to ensure agricultural production against the loss of heavily relied upon managed pollinators. Local plant communities provision wild bees with crucial floral and nesting resources, but the distribution of floristic diversity among habitat types in North American agricultural landscapes and its effect on pollinators are diverse and poorly understood, especially in orchard systems. We documented floristic diversity in typical mid-Atlantic commercial apple (Malus domestica Borkh.) orchards including the forest and orchard-forest edge ("edge") habitats surrounding orchards in a heterogeneous landscape in south-central Pennsylvania, USA. We also assessed the correlation between plant richness and orchard pollinator communities. In this apple production region, edge habitats are the most species rich, supporting 146 out of 202 plant species recorded in our survey. Plant species richness in the orchard and edge habitats were significant predictors of bee species richness and abundance in the orchard, as well as landscape area of the forest and edge habitats. Both the quantity and quality of forest and edges close to orchards play a significant role in provisioning a diverse wild bee community in this agroecosystem. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. THE RELATIONSHIP BETWEEN THE DIVERSITY OF EMPLOYEES AND ORGANIZATIONAL PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Latif Abdul Ridha ATIYAH

    2016-12-01

    Full Text Available The current research aims to analyze the diversity of workers and its influence on the organizational performance. The success of an organization is achieved by bringing new creative ideas. Thus, adopting diversity management and diverse workforce inside organization, will create a behavior to add several traits that will enhance the organizational performance by adapting the current work environment to the future work plan. The goal of the research is to identify the impact of diversity in being an independent variant resembled by: (Type, sex, age, religion, ethnicity and the other one the organizational performance in being a dependent (Related variant resembled by (market share, sales growth, customer satisfaction, the release cycle of a new product. The present research reached a number of conclusions, their highlights resembled by the importance of diversity relying on diversity strategy on improving the current products while offering continuous and effective support to the projects of development and research, considering it as the main tool to support the success of effective organizational performance. The results generally confirmed the relation and the expected impact between the effective organization performance and diversity in the researched organization.

  10. Fasciola hepatica demonstrates high levels of genetic diversity, a lack of population structure and high gene flow: possible implications for drug resistance.

    Science.gov (United States)

    Beesley, Nicola J; Williams, Diana J L; Paterson, Steve; Hodgkinson, Jane

    2017-01-01

    Fasciola hepatica, the liver fluke, is a trematode parasite of considerable economic importance to the livestock industry and is a re-emerging zoonosis that poses a risk to human health in F. hepatica-endemic areas worldwide. Drug resistance is a substantial threat to the current and future control of F. hepatica, yet little is known about how the biology of the parasite influences the development and spread of resistance. Given that F. hepatica can self-fertilise and therefore inbreed, there is the potential for greater population differentiation and an increased likelihood of recessive alleles, such as drug resistance genes, coming together. This could be compounded by clonal expansion within the snail intermediate host and aggregation of parasites of the same genotype on pasture. Alternatively, widespread movement of animals that typically occurs in the UK could promote high levels of gene flow and prevent population differentiation. We identified clonal parasites with identical multilocus genotypes in 61% of hosts. Despite this, 84% of 1579 adult parasites had unique multilocus genotypes, which supports high levels of genotypic diversity within F. hepatica populations. Our analyses indicate a selfing rate no greater than 2%, suggesting that this diversity is in part due to the propensity for F. hepatica to cross-fertilise. Finally, although we identified high genetic diversity within a given host, there was little evidence for differentiation between populations from different hosts, indicating a single panmictic population. This implies that, once those emerge, anthelmintic resistance genes have the potential to spread rapidly through liver fluke populations. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Production of High-Intensity, Highly Charged Ions

    CERN Document Server

    Gammino, S.

    2013-12-16

    In the past three decades, the development of nuclear physics facilities for fundamental and applied science purposes has required an increasing current of multicharged ion beams. Multiple ionization implies the formation of dense and energetic plasmas, which, in turn, requires specific plasma trapping configurations. Two types of ion source have been able to produce very high charge states in a reliable and reproducible way: electron beam ion sources (EBIS) and electron cyclotron resonance ion sources (ECRIS). Multiple ionization is also obtained in laser-generated plasmas (laser ion sources (LIS)), where the high-energy electrons and the extremely high electron density allow step-by-step ionization, but the reproducibility is poor. This chapter discusses the atomic physics background at the basis of the production of highly charged ions and describes the scientific and technological features of the most advanced ion sources. Particular attention is paid to ECRIS and the latest developments, since they now r...

  12. Identity, Diversity and Diversity Management

    DEFF Research Database (Denmark)

    Holck, Lotte; Muhr, Sara Louise; Villeseche, Florence

    2016-01-01

    – The work can encourage policy makers, diversity and HR managers to question their own practices and assumptions leading to more theoretical informed diversity management practices. Originality/value – The theoretical connections between identity and diversity literature have so far not been reviewed......The purpose of this paper is to examine the relationship between the identity and diversity literatures and discuss how a better understanding of the theoretical connections between the two informs both diversity research and diversity management practices. Design/methodology/approach – Literature...... and limitations – is crucial for successful diversity management research and practice. Research limitations/implications – The authors argue for a better understanding of differences, overlaps and limits of different identity perspectives, and for a stronger engagement with practice. Practical implications...

  13. Examining the resilience of national energy systems: Measurements of diversity in production-based and consumption-based electricity in the globalization of trade networks

    International Nuclear Information System (INIS)

    Kharrazi, Ali; Sato, Masahiro; Yarime, Masaru; Nakayama, Hirofumi; Yu, Yadong; Kraines, Steven

    2015-01-01

    Energy is a critical component of achieving sustainable development. In addition to the three aspects of promoting access, renewables, and efficiency, the dimension of resilience in energy systems should also considered. The implementation of resilient energy systems requires a quantitative understanding of the socio-economic practices underlying such systems. Specifically, in line with the increasing globalization of trade, there remains a critical knowledge gap on the link between embodied energy in the production and consumption of traded goods. To bridge this knowledge gap, we investigate the resilience of global energy systems through an examination of a diversity measure of global embodied electricity trade based on multi-regional input-output (MRIO) networks. The significance of this research lies in its ability to utilize high resolution MRIO data sets in assessing the resilience of national energy systems. This research indicates that secure and responsible consumption requires the diversification of not only energy generation but also energy imports. This research will lay the ground for further research in the governance of resilience in global energy networks. - Highlights: • We examine the resilience of global embodied energy based on (MRIO) trade networks. • We propose a secure and responsible mode of thinking for national energy consumption. • Secure & responsible consumption requires diversity in energy generation and imports.

  14. Diversity in global maize germplasm: Characterization and utilization

    Indian Academy of Sciences (India)

    Maize (Zea mays L.) is not only of worldwide importance as a food, feed and as a source of diverse industrially important products, but is also a model genetic organism with immense genetic diversity. Although it was first domesticated in Mexico, maize landraces are widely found across the continents. Several studies in ...

  15. Genetic diversity of Pakistani maize genotypes using chromosome ...

    African Journals Online (AJOL)

    For improvement of maize crop presence of genetic diversity in the germplasm is very important. This study was conducted to determine genetic diversity among 17 Pakistani maize genotypes using 10 simple sequence repeat (SSR) primer sets. All the amplification products were in the range of <250-750 bp. To estimate the ...

  16. The development of isomerization catalysts for production of high-octane products

    Energy Technology Data Exchange (ETDEWEB)

    Pedrosa, A.M. Garrido; Melo, D.M.A.; Araujo, A.S. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Dept. de Quimica; Souza, M.J.B.; Silva, A.O.S. [Universidade Federal do Rio Grande do Norte, Natal, RN (Brazil). Dept. de Engenharia Quimica

    2004-07-01

    In current petroleum industry, paraffins larger than C5 are used for catalytic reform. The catalytic reform is one of the most important processes for petroleum refine in reason of all reactions they drive to production of high-octane products. Reformate has high-octane products, but they contain 60% aromatics. Isomerization of C5- C7 can improve the octane number. The octane number of n-heptane is zero and increases after isomerization. For tri branched C7, the octane number reaches 113, which is higher than that of benzene. So, isomerization of C5-C7 is suggested to be a reasonable way to replace or partly replace the catalytic reforming process. It can decrease aromatics content with enhancement of octane number. Liquid acid catalysts were widely used in chemical industry in past decades. However, they face strong environmental challenges. The heavy corrosion of the reactor system is one of the main problems. Thus, solid acid catalysts are investigated for the isomerization reactions. The aim of this work is to develop a catalysts for the production of reformate products. Isomerization is catalyzed by metal-acid bifunctional catalysts. The metal components aid in hydrogenation, while the support, such as, zirconium, clays or zeolites, is the acidic component. (author)

  17. High Volume Manufacturing and Field Stability of MEMS Products

    Science.gov (United States)

    Martin, Jack

    Low volume MEMS/NEMS production is practical when an attractive concept is implemented with business, manufacturing, packaging, and test support. Moving beyond this to high volume production adds requirements on design, process control, quality, product stability, market size, market maturity, capital investment, and business systems. In a broad sense, this chapter uses a case study approach: It describes and compares the silicon-based MEMS accelerometers, pressure sensors, image projection systems, and gyroscopes that are in high volume production. Although they serve several markets, these businesses have common characteristics. For example, the manufacturing lines use automated semiconductor equipment and standard material sets to make consistent products in large quantities. Standard, well controlled processes are sometimes modified for a MEMS product. However, novel processes that cannot run with standard equipment and material sets are avoided when possible. This reliance on semiconductor tools, as well as the organizational practices required to manufacture clean, particle-free products partially explains why the MEMS market leaders are integrated circuit manufacturers. There are other factors. MEMS and NEMS are enabling technologies, so it can take several years for high volume applications to develop. Indeed, market size is usually a strong function of price. This becomes a vicious circle, because low price requires low cost - a result that is normally achieved only after a product is in high volume production. During the early years, IC companies reduced cost and financial risk by using existing facilities for low volume MEMS production. As a result, product architectures are partially determined by capabilities developed for previous products. This chapter includes a discussion of MEMS product architecture with particular attention to the impact of electronic integration, packaging, and surfaces. Packaging and testing are critical, because they are

  18. Molecular Technique to Understand Deep Microbial Diversity

    Science.gov (United States)

    Vaishampayan, Parag A.; Venkateswaran, Kasthuri J.

    2012-01-01

    Current sequencing-based and DNA microarray techniques to study microbial diversity are based on an initial PCR (polymerase chain reaction) amplification step. However, a number of factors are known to bias PCR amplification and jeopardize the true representation of bacterial diversity. PCR amplification of the minor template appears to be suppressed by the exponential amplification of the more abundant template. It is widely acknowledged among environmental molecular microbiologists that genetic biosignatures identified from an environment only represent the most dominant populations. The technological bottleneck has overlooked the presence of the less abundant minority population, and underestimated their role in the ecosystem maintenance. To generate PCR amplicons for subsequent diversity analysis, bacterial l6S rRNA genes are amplified by PCR using universal primers. Two distinct PCR regimes are employed in parallel: one using normal and the other using biotinlabeled universal primers. PCR products obtained with biotin-labeled primers are mixed with streptavidin-labeled magnetic beads and selectively captured in the presence of a magnetic field. Less-abundant DNA templates that fail to amplify in this first round of PCR amplification are subjected to a second round of PCR using normal universal primers. These PCR products are then subjected to downstream diversity analyses such as conventional cloning and sequencing. A second round of PCR amplified the minority population and completed the deep diversity picture of the environmental sample.

  19. Range-edge genetic diversity: locally poor extant southern patches maintain a regionally diverse hotspot in the seagrass Zostera marina.

    Science.gov (United States)

    Diekmann, Onno E; Serrão, Ester A

    2012-04-01

    Refugial populations at the rear edge are predicted to contain higher genetic diversity than those resulting from expansion, such as in post-glacial recolonizations. However, peripheral populations are also predicted to have decreased diversity compared to the centre of a species' distribution. We aim to test these predictions by comparing genetic diversity in populations at the limits of distribution of the seagrass Zostera marina, with populations in the species' previously described central diversity 'hotspot'. Zostera marina populations show decreased allelic richness, heterozygosity and genotypic richness in both the 'rear' edge and the 'leading' edge compared to the diversity 'hotspot' in the North Sea/Baltic region. However, when populations are pooled, genetic diversity at the southern range is as high as in the North Sea/Baltic region while the 'leading edge' remains low in genetic diversity. The decreased genetic diversity in these southern Iberian populations compared to more central populations is possibly the effect of drift because of small effective population size, as a result of reduced habitat, low sexual reproduction and low gene flow. However, when considering the whole southern edge of distribution rather than per population, diversity is as high as in the central 'hotspot' in the North Sea/Baltic region. We conclude that diversity patterns assessed per population can mask the real regional richness that is typical of rear edge populations, which have played a key role in the species biogeographical history and as marginal diversity hotspots have very high conservation value. © 2012 Blackwell Publishing Ltd.

  20. Nitrogen partitioning and milk production of dairy cows grazing simple and diverse pastures.

    Science.gov (United States)

    Totty, V K; Greenwood, S L; Bryant, R H; Edwards, G R

    2013-01-01

    Research was conducted to examine the effects of a diverse pasture mix on dry matter intake, milk yield, and N partitioning of lactating dairy cows. A pasture containing only ryegrass and white clover (RG), or high-sugar ryegrass and white clover (HS), was compared with a diverse pasture mix (HSD) including chicory, plantain, lotus, high-sugar ryegrass, and white clover. The experiment was conducted over a 10-d period using 3 groups of 12 cows in late lactation. No difference was observed in dry matter (14.3 kg of dry matter/cow per day) or N (583 g of N/cow per day) intake between treatments. The cows grazing the HSD pasture had an increased milk yield (16.9 kg/d) compared with those grazing the simple RG and HS pastures (15.2 and 14.7 kg/d, respectively). However, no differences were observed in milk solids yield for the 3 treatments. A tendency toward greater milk protein yields in the HSD group resulted in improved N use efficiency for milk of 20.4% from the cows fed HSD, compared with 17.8 and 16.7% from cows in the RG and HS treatments, respectively. Urinary N excretion was lower from the cows fed HSD, at 353.8 g/d, compared with 438.3 and 426.6 g/d for cows fed RG and HS, respectively. These results suggest that the use of pastures containing chicory, lotus, and plantain can contribute to the goal of reducing N losses from cows in late lactation. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  1. High Inter-Individual Diversity of Point Mutations, Insertions, and Deletions in Human Influenza Virus Nucleoprotein-Specific Memory B Cells.

    Directory of Open Access Journals (Sweden)

    Sven Reiche

    Full Text Available The diversity of virus-specific antibodies and of B cells among different individuals is unknown. Using single-cell cloning of antibody genes, we generated recombinant human monoclonal antibodies from influenza nucleoprotein-specific memory B cells in four adult humans with and without preceding influenza vaccination. We examined the diversity of the antibody repertoires and found that NP-specific B cells used numerous immunoglobulin genes. The heavy chains (HCs originated from 26 and the kappa light chains (LCs from 19 different germ line genes. Matching HC and LC chains gave rise to 43 genetically distinct antibodies that bound influenza NP. The median lengths of the CDR3 of the HC, kappa and lambda LC were 14, 9 and 11 amino acids, respectively. We identified changes at 13.6% of the amino acid positions in the V gene of the antibody heavy chain, at 8.4% in the kappa and at 10.6 % in the lambda V gene. We identified somatic insertions or deletions in 8.1% of the variable genes. We also found several small groups of clonal relatives that were highly diversified. Our findings demonstrate broadly diverse memory B cell repertoires for the influenza nucleoprotein. We found extensive variation within individuals with a high number of point mutations, insertions, and deletions, and extensive clonal diversification. Thus, structurally conserved proteins can elicit broadly diverse and highly mutated B-cell responses.

  2. Workforce Diversity And Organizational Communication: Analysis Of Human Capital Performance And Productivity

    OpenAIRE

    Ephraim A. Okoro; Melvin C. Washington

    2012-01-01

    The twenty-first century organizations are increasingly becoming multicultural workplaces for communication. This paper explores recent literature on the increasing global influence of workforce diversity and its affect on workplace communication. It provides a model for the discussion of the opportunities and challenges of diversity in the workplace. The paper then provides an analytical framework that guides readers with practical ideas that can assist them in their endeavors to effectively...

  3. Diversity of picoeukaryotes at an oligotrophic site off the Northeastern Red Sea Coast.

    Science.gov (United States)

    Acosta, Francisco; Ngugi, David Kamanda; Stingl, Ulrich

    2013-08-20

    Picoeukaryotes are protists ≤ 3 μm composed of a wide diversity of taxonomic groups. They are an important constituent of the ocean's microbiota and perform essential ecological roles in marine nutrient and carbon cycles. Despite their importance, the true extent of their diversity has only recently been uncovered by molecular surveys that resulted in the discovery of a substantial number of previously unknown groups. No study on picoeukaryote diversity has been conducted so far in the main Red Sea basin-a unique marine environment characterized by oligotrophic conditions, high levels of irradiance, high salinity and increased water temperature. We sampled surface waters off the coast of the northeastern Red Sea and analyzed the picoeukaryotic diversity using Sanger-based clone libraries of the 18S rRNA gene in order to produce high quality, nearly full-length sequences. The community captured by our approach was dominated by three main phyla, the alveolates, stramenopiles and chlorophytes; members of Radiolaria, Cercozoa and Haptophyta were also found, albeit in low abundances. Photosynthetic organisms were especially diverse and abundant in the sample, confirming the importance of picophytoplankton for primary production in the basin as well as indicating the existence of numerous ecological micro-niches for this trophic level in the upper euphotic zone. Heterotrophic organisms were mostly composed of the presumably parasitic Marine Alveolates (MALV) and the presumably bacterivorous Marine Stramenopiles (MAST) groups. A small number of sequences that did not cluster closely with known clades were also found, especially in the MALV-II group, some of which could potentially belong to novel clades. This study provides the first snapshot of the picoeukaryotic diversity present in surface waters of the Red Sea, hence setting the stage for large-scale surveying and characterization of the eukaryotic diversity in the entire basin. Our results indicate that the

  4. High diversity in cretaceous ichthyosaurs from Europe prior to their extinction.

    Directory of Open Access Journals (Sweden)

    Valentin Fischer

    Full Text Available BACKGROUND: Ichthyosaurs are reptiles that inhabited the marine realm during most of the Mesozoic. Their Cretaceous representatives have traditionally been considered as the last survivors of a group declining since the Jurassic. Recently, however, an unexpected diversity has been described in Upper Jurassic-Lower Cretaceous deposits, but is widely spread across time and space, giving small clues on the adaptive potential and ecosystem control of the last ichthyosaurs. The famous but little studied English Gault Formation and 'greensands' deposits (the Upper Greensand Formation and the Cambridge Greensand Member of the Lower Chalk Formation offer an unprecedented opportunity to investigate this topic, containing thousands of ichthyosaur remains spanning the Early-Late Cretaceous boundary. METHODOLOGY/PRINCIPAL FINDINGS: To assess the diversity of the ichthyosaur assemblage from these sedimentary bodies, we recognized morphotypes within each type of bones. We grouped these morphotypes together, when possible, by using articulated specimens from the same formations and from new localities in the Vocontian Basin (France; a revised taxonomic scheme is proposed. We recognize the following taxa in the 'greensands': the platypterygiines 'Platypterygius' sp. and Sisteronia seeleyi gen. et sp. nov., indeterminate ophthalmosaurines and the rare incertae sedis Cetarthrosaurus walkeri. The taxonomic diversity of late Albian ichthyosaurs now matches that of older, well-known intervals such as the Toarcian or the Tithonian. Contrasting tooth shapes and wear patterns suggest that these ichthyosaurs colonized three distinct feeding guilds, despite the presence of numerous plesiosaur taxa. CONCLUSION/SIGNIFICANCE: Western Europe was a diversity hot-spot for ichthyosaurs a few million years prior to their final extinction. By contrast, the low diversity in Australia and U.S.A. suggests strong geographical disparities in the diversity pattern of Albian

  5. Microbial diversity and their roles in the vinegar fermentation process.

    Science.gov (United States)

    Li, Sha; Li, Pan; Feng, Feng; Luo, Li-Xin

    2015-06-01

    Vinegar is one of the oldest acetic acid-diluted solution products in the world. It is produced from any fermentable sugary substrate by various fermentation methods. The final vinegar products possess unique functions, which are endowed with many kinds of compounds formed in the fermentation process. The quality of vinegar is determined by many factors, especially by the raw materials and microbial diversity involved in vinegar fermentation. Given that metabolic products from the fermenting strains are directly related to the quality of the final products of vinegar, the microbial diversity and features of the dominant strains involved in different fermentation stages should be analyzed to improve the strains and stabilize fermentation. Moreover, although numerous microbiological studies have been conducted to examine the process of vinegar fermentation, knowledge about microbial diversity and their roles involved in fermentation is still fragmentary and not systematic enough. Therefore, in this review, the dominant microorganism species involved in the stages of alcoholic fermentation and acetic acid fermentation of dissimilar vinegars were summarized. We also summarized various physicochemical properties and crucial compounds in disparate types of vinegar. Furthermore, the merits and drawbacks of vital fermentation methods were generalized. Finally, we described in detail the relationships among microbial diversity, raw materials, fermentation methods, physicochemical properties, compounds, functionality, and final quality of vinegar. The integration of this information can provide us a detailed map about the microbial diversity and function involved in vinegar fermentation.

  6. Farmers' contributions to the conservation of tree diversity in the Groundnut Basin, Senegal

    Institute of Scientific and Technical Information of China (English)

    Antoine Sambou; Bienvenu Sambou; Anders R(ae)bild

    2017-01-01

    Tree diversity in West Africa is threatened by intensified land uses and salinization,and farmers' role in conservation of tree species is unclear.We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes.Inventories were carried out in three villages in the Groundnut Basin in Senegal,assessing tree diversity,density and crown cover.Tree diversity as assessed by species accumulation curves was high in forests,but cultivated landscapes had comparable or almost comparable diversity,especially in the cases where the forest was planted or was affected by charcoal production.However,the occurrence of exotic species was higher in cultivated parts of the landscape,and although many species were in common,ordination plots indicated that forests and cultivated landscapes to some degree had different species composition.Salinity had a strong influence on vegetation,not only in the tans (salt marshes) but also across the other landscape classes.In conclusion,agroforestry landscapes in the three villages harbor considerable tree diversity,but insufficient to fully conserve the tree species.We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

  7. Substrate Scope of O-Methyltransferase from Streptomyces peucetius for Biosynthesis of Diverse Natural Products Methoxides.

    Science.gov (United States)

    Parajuli, Prakash; Pandey, Ramesh Prasad; Nguyen, Thi Huyen Trang; Dhakal, Dipesh; Sohng, Jae Kyung

    2018-04-01

    Methylation is a common post-modification reaction that is observed during the biosynthesis of secondary metabolites produced by plants and microorganisms. Based on the sequence information from Streptomyces peucetius ATCC27952, a putative O-methyltransferase (OMT) gene SpOMT7740 was polymerase chain reaction amplified and cloned into E. coli BL21 (DE3) host to test the substrate promiscuity and conduct functional characterization. In vitro and in vivo reaction assays were carried out over various classes of substrates: flavonoids (flavonol, flavones, and isoflavonoid), chalcones, anthraquinones, anthracyclines, and sterol molecules, and the applications in synthesizing diverse classes of O-methoxy natural products were also illustrated. SpOMT7740 catalyzed the O-methylation reaction to form various natural and non-natural O-methoxides, includes 7-hydroxy-8-O-methoxy flavone, 3-O-methoxy flavone, three mono-, di-, and tri-O-methoxy genistein, mono-O-methoxy phloretin, mono-O-methoxy luteolin, 3-O-methoxy β-sitosterol, and O-methoxy anthraquinones (emodin and aloe emodin) and O-methoxy anthracycline (daunorubicin) exhibiting diverse substrate flexibility. Daunorubicin is a native secondary metabolite of S. peucetius. Among the compounds tested, 7,8-dihydroxyflavone was the best substrate for bioconversion to 7-hydroxy-8-O-methoxy flavone, and it was structurally elucidated. This enzyme showed a flexible catalysis over the given ranges of temperature, pH, and divalent cationic conditions for O-methylation.

  8. Amino acid composition reveals functional diversity of zooplankton in tropical lakes related to geography, taxonomy and productivity.

    Science.gov (United States)

    Aranguren-Riaño, Nelson J; Guisande, Cástor; Shurin, Jonathan B; Jones, Natalie T; Barreiro, Aldo; Duque, Santiago R

    2018-04-16

    Variation in resource use among species determines their potential for competition and co-existence, as well as their impact on ecosystem processes. Planktonic crustaceans consume a range of micro-organisms that vary among habitats and species, but these differences in resource consumption are difficult to characterize due to the small size of the organisms. Consumers acquire amino acids from their diet, and the composition of tissues reflects both the use of different resources and their assimilation in proteins. We examined the amino acid composition of common crustacean zooplankton from 14 tropical lakes in Colombia in three regions (the Amazon floodplain, the eastern range of the Andes, and the Caribbean coast). Amino acid composition varied significantly among taxonomic groups and the three regions. Functional richness in amino acid space was greatest in the Amazon, the most productive region, and tended to be positively related to lake trophic status, suggesting the niche breadth of the community could increase with ecosystem productivity. Functional evenness increased with lake trophic status, indicating that species were more regularly distributed within community-wide niche space in more productive lakes. These results show that zooplankton resource use in tropical lakes varies with both habitat and taxonomy, and that lake productivity may affect community functional diversity and the distribution of species within niche space.

  9. Cacao Cultivation under Diverse Shade Tree Cover Allows High Carbon Storage and Sequestration without Yield Losses.

    Science.gov (United States)

    Abou Rajab, Yasmin; Leuschner, Christoph; Barus, Henry; Tjoa, Aiyen; Hertel, Dietrich

    2016-01-01

    One of the main drivers of tropical forest loss is their conversion to oil palm, soy or cacao plantations with low biodiversity and greatly reduced carbon storage. Southeast Asian cacao plantations are often established under shade tree cover, but are later converted to non-shaded monocultures to avoid resource competition. We compared three co-occurring cacao cultivation systems (3 replicate stands each) with different shade intensity (non-shaded monoculture, cacao with the legume Gliricidia sepium shade trees, and cacao with several shade tree species) in Sulawesi (Indonesia) with respect to above- and belowground biomass and productivity, and cacao bean yield. Total biomass C stocks (above- and belowground) increased fivefold from the monoculture to the multi-shade tree system (from 11 to 57 Mg ha-1), total net primary production rose twofold (from 9 to 18 Mg C ha-1 yr-1). This increase was associated with a 6fold increase in aboveground biomass, but only a 3.5fold increase in root biomass, indicating a clear shift in C allocation to aboveground tree organs with increasing shade for both cacao and shade trees. Despite a canopy cover increase from 50 to 93%, cacao bean yield remained invariant across the systems (variation: 1.1-1.2 Mg C ha-1 yr-1). The monocultures had a twice as rapid leaf turnover suggesting that shading reduces the exposure of cacao to atmospheric drought, probably resulting in greater leaf longevity. Thus, contrary to general belief, cacao bean yield does not necessarily decrease under shading which seems to reduce physical stress. If planned properly, cacao plantations under a shade tree cover allow combining high yield with benefits for carbon sequestration and storage, production system stability under stress, and higher levels of animal and plant diversity.

  10. Diversity as strategy.

    Science.gov (United States)

    Thomas, David A

    2004-09-01

    IBM's turnaround in the last decade is an impressive and well-documented business story. But behind that success is a less told people story, which explains how the corporation dramatically altered its already diverse composition and created millions of dollars in new business. By the time Lou Gerstner took the helm in 1993, IBM had a long history of progressive management when it came to civil rights and equal-opportunity employment. But Gerstner felt IBM wasn't taking full advantage of a diverse market for talent, nor was it maximizing the potential of its diverse customer and employee base. So in 1995, he launched a diversity task force initiative to uncover and understand differences among people within the organization and find ways to appeal to an even broader set of employees and customers. Gerstner established a task force for each of eight constituencies: Asians; blacks; the gay, lesbian, bisexual, transgendered community; Hispanics; white men; Native Americans; people with disabilities; and women. He asked the task forces to research four questions: What does your constituency need to feel welcome and valued at IBM? What can the corporation do, in partnership with your group, to maximize your constituency's productivity? What can the corporation do to influence your constituency's buying decisions so that IBM is seen as a preferred solution provider? And with which external organizations should IBM form relationships to better understand the needs of your constituency? The answers to these questions became the basis for IBM's diversity strategy. Thomas stresses that four factors are key to implementing any major change initiative: strong support from company leaders, an employee base that is fully engaged with the initiative, management practices that are integrated and aligned with the effort, and a strong and well-articulated business case for action. All four elements have helped IBM make diversity a key corporate strategy tied to real growth.

  11. CVD growth of large-area and high-quality HfS2 nanoforest on diverse substrates

    Science.gov (United States)

    Zheng, Binjie; Wang, Zegao; Qi, Fei; Wang, Xinqiang; Yu, Bo; Zhang, Wanli; Chen, Yuanfu

    2018-03-01

    Two-dimensional layered transition metal dichalcogenides (TMDs) have attracted burgeoning attention due to their various properties and wide potential applications. As a new TMD, hafnium disulfide (HfS2) is theoretically predicted to have better electrical performance than widely studied MoS2. The experimental researches also confirmed the extraordinary feature in electronics and optoelectronics. However, the maximal device performance may not be achieved due to its own limitation of planar structure and challenge of transfer without contamination. Here, through the chemical vapor deposition (CVD) technique, inch-size HfS2 nanoforest has been directly grown on diverse objective substrates covering insulating, semiconducting and conducting substrates. This direct CVD growth without conventional transfer process avoids contamination and degradation in quality, suggesting its promising and wide applications in high-quality and multifarious devices. It is noted that all the HfS2 nanoforests grown on diverse substrates are constructed with vertically aligned few-layered HfS2 nanosheets with high crystalline quality and edge orientation. Moreover, due to its unique structure, the HfS2 nanoforest owns abundant exposed edge sites and large active surface area, which is essential to apply in high-performance catalyst, sensor, and energy storage or field emitter.

  12. Evolutionary history determines how plant productivity responds to phylogenetic diversity and species richness

    Directory of Open Access Journals (Sweden)

    Mark A. Genung

    2014-03-01

    Full Text Available The relationship between biodiversity and ecosystem function has received a great deal of attention in ecological research and recent results, from re-analyses, suggest that ecosystem function improves with increases in phylogenetic diversity. However, many of these results have been generalized across a range of different species and clades, and plants with different evolutionary histories could display different relationships between biodiversity and ecosystem function. To experimentally test this hypothesis, we manipulated species richness and phylogenetic diversity using 26 species from two subgenera of the genus Eucalyptus (subgenus Eucalyptus and subgenus Symphyomyrtus. We found that plant biomass (a measurement of ecosystem function sometimes, but not always, responded to increases in species richness and phylogenetic diversity. Specifically, Symphyomyrtus plants showed a positive response while no comparable effect was observed for Eucalyptus plants, showing that responses to biodiversity can vary across different phylogenetic groups. Our results show that the impacts of evolutionary history may complicate the relationship between the diversity of plant communities and plant biomass.

  13. Engaging Students in the Research Process: Comparing Approaches Used with Diverse Learners in Two Urban High School Classrooms

    Science.gov (United States)

    Lawrence, Salika A.; Jefferson, Tiffany; Osborn, Nancy

    2017-01-01

    This paper describes instructional choices used by two high school teachers to engage students in the research process. Working with diverse learners in large urban high schools, the teachers used different approaches to support students' through the research process. The teachers' intentional teaching helped to engage students through structured…

  14. The future of textile production in high wage countries

    Science.gov (United States)

    Kemper, M.; Gloy, Y.-S.; Gries, T.

    2017-10-01

    It is undisputed that smart production in the context of industry 4.0 offers significant potential for industrial production in Germany. Exploiting this potential provides an opportunity to meet the growing competitive pressure for textile production in high-wage Germany. The complete cross-linking of textile mills towards Textile Production 4.0 means substantial savings. However, currently there are still some challenges that have to be overcome on the long way to Textile Production 4.0. This paper initially reflects the particular challenges of textile production in high-wage Germany. Later, the vision of the future of smart textile production will be outlined. In addition, first pilot solutions and current research approaches which pave the way for Textile Production 4.0 are described.

  15. The global diversion of pharmaceutical drugs. India: the third largest illicit opium producer?

    Science.gov (United States)

    Paoli, Letizia; Greenfield, Victoria A; Charles, Molly; Reuter, Peter

    2009-03-01

    This paper explores India's role in the world illicit opiate market, particularly its role as a producer. India, a major illicit opiate consumer, is also the sole licensed exporter of raw opium: this unique status may be enabling substantial diversion to the illicit market. Participant observation and interviews were carried out at eight different sites. Information was also drawn from all standard secondary sources and the analysis of about 180 drug-related criminal proceedings reviewed by Indian High Courts and the Supreme Court from 1985 to 2001. Diversion from licit opium production takes place on such a large scale that India may be the third largest illicit opium producer after Afghanistan and Burma. With the possible exceptions of 2005 and 2006, 200-300 tons of India's opium may be diverted yearly. After estimating India's opiate consumption on the basis of UN-reported prevalence estimates, we find that diversion from licit production might have satisfied a quarter to more than a third of India's illicit opiate demand to 2004. India is not only among the world's largest consumer of illicit opiates but also one of the largest illicit opium producers. In contrast to all other illicit producers, India owes the latter distinction not to blatantly illicit cultivation but to diversion from licit cultivation. India's experience suggests the difficulty of preventing substantial leakage, even in a relatively well-governed nation.

  16. Determinants of Aggregate Agricultural Productivity among High ...

    African Journals Online (AJOL)

    African Journal of Food, Agriculture, Nutrition and Development ... Determinants of Aggregate Agricultural Productivity among High External Input Technology Farms in a ... of aggregate agricultural productivity in an environment where policy on ... to increase the farm sizes through re-examination of the existing land laws.

  17. Population genetic diversity and fitness in multiple environments

    Directory of Open Access Journals (Sweden)

    McGreevy Thomas J

    2010-07-01

    Full Text Available Abstract Background When a large number of alleles are lost from a population, increases in individual homozygosity may reduce individual fitness through inbreeding depression. Modest losses of allelic diversity may also negatively impact long-term population viability by reducing the capacity of populations to adapt to altered environments. However, it is not clear how much genetic diversity within populations may be lost before populations are put at significant risk. Development of tools to evaluate this relationship would be a valuable contribution to conservation biology. To address these issues, we have created an experimental system that uses laboratory populations of an estuarine crustacean, Americamysis bahia with experimentally manipulated levels of genetic diversity. We created replicate cultures with five distinct levels of genetic diversity and monitored them for 16 weeks in both permissive (ambient seawater and stressful conditions (diluted seawater. The relationship between molecular genetic diversity at presumptive neutral loci and population vulnerability was assessed by AFLP analysis. Results Populations with very low genetic diversity demonstrated reduced fitness relative to high diversity populations even under permissive conditions. Population performance decreased in the stressful environment for all levels of genetic diversity relative to performance in the permissive environment. Twenty percent of the lowest diversity populations went extinct before the end of the study in permissive conditions, whereas 73% of the low diversity lines went extinct in the stressful environment. All high genetic diversity populations persisted for the duration of the study, although population sizes and reproduction were reduced under stressful environmental conditions. Levels of fitness varied more among replicate low diversity populations than among replicate populations with high genetic diversity. There was a significant correlation

  18. Culture-independent discovery of natural products from soil metagenomes.

    Science.gov (United States)

    Katz, Micah; Hover, Bradley M; Brady, Sean F

    2016-03-01

    Bacterial natural products have proven to be invaluable starting points in the development of many currently used therapeutic agents. Unfortunately, traditional culture-based methods for natural product discovery have been deemphasized by pharmaceutical companies due in large part to high rediscovery rates. Culture-independent, or "metagenomic," methods, which rely on the heterologous expression of DNA extracted directly from environmental samples (eDNA), have the potential to provide access to metabolites encoded by a large fraction of the earth's microbial biosynthetic diversity. As soil is both ubiquitous and rich in bacterial diversity, it is an appealing starting point for culture-independent natural product discovery efforts. This review provides an overview of the history of soil metagenome-driven natural product discovery studies and elaborates on the recent development of new tools for sequence-based, high-throughput profiling of environmental samples used in discovering novel natural product biosynthetic gene clusters. We conclude with several examples of these new tools being employed to facilitate the recovery of novel secondary metabolite encoding gene clusters from soil metagenomes and the subsequent heterologous expression of these clusters to produce bioactive small molecules.

  19. Yeast diversity and native vigor for flavor phenotypes.

    Science.gov (United States)

    Carrau, Francisco; Gaggero, Carina; Aguilar, Pablo S

    2015-03-01

    Saccharomyces cerevisiae, the yeast used widely for beer, bread, cider, and wine production, is the most resourceful eukaryotic model used for genetic engineering. A typical concern about using engineered yeasts for food production might be negative consumer perception of genetically modified organisms. However, we believe the true pitfall of using genetically modified yeasts is their limited capacity to either refine or improve the sensory properties of fermented foods under real production conditions. Alternatively, yeast diversity screening to improve the aroma and flavors could offer groundbreaking opportunities in food biotechnology. We propose a 'Yeast Flavor Diversity Screening' strategy which integrates knowledge from sensory analysis and natural whole-genome evolution with information about flavor metabolic networks and their regulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. High risks of losing genetic diversity in an endemic Mauritian gecko: implications for conservation.

    Directory of Open Access Journals (Sweden)

    Steeves Buckland

    Full Text Available Genetic structure can be a consequence of recent population fragmentation and isolation, or a remnant of historical localised adaptation. This poses a challenge for conservationists since misinterpreting patterns of genetic structure may lead to inappropriate management. Of 17 species of reptile originally found in Mauritius, only five survive on the main island. One of these, Phelsuma guimbeaui (lowland forest day gecko, is now restricted to 30 small isolated subpopulations following severe forest fragmentation and isolation due to human colonisation. We used 20 microsatellites in ten subpopulations and two mitochondrial DNA (mtDNA markers in 13 subpopulations to: (i assess genetic diversity, population structure and genetic differentiation of subpopulations; (ii estimate effective population sizes and migration rates of subpopulations; and (iii examine the phylogenetic relationships of haplotypes found in different subpopulations. Microsatellite data revealed significant population structure with high levels of genetic diversity and isolation by distance, substantial genetic differentiation and no migration between most subpopulations. MtDNA, however, showed no evidence of population structure, indicating that there was once a genetically panmictic population. Effective population sizes of ten subpopulations, based on microsatellite markers, were small, ranging from 44 to 167. Simulations suggested that the chance of survival and allelic diversity of some subpopulations will decrease dramatically over the next 50 years if no migration occurs. Our DNA-based evidence reveals an urgent need for a management plan for the conservation of P. guimbeaui. We identified 18 threatened and 12 viable subpopulations and discuss a range of management options that include translocation of threatened subpopulations to retain maximum allelic diversity, and habitat restoration and assisted migration to decrease genetic erosion and inbreeding for the viable

  1. Transcriptional diversity and regulation across time and states

    DEFF Research Database (Denmark)

    Vitting-Seerup, Kristoffer

    Originally the production of RNA copies from genes was thought to serve just as an intermediary step in the production of proteins. This view has however drastically changed with the emergence of several important functions of RNA. It has been found that the production of RNA also serves as to in......Originally the production of RNA copies from genes was thought to serve just as an intermediary step in the production of proteins. This view has however drastically changed with the emergence of several important functions of RNA. It has been found that the production of RNA also serves...... is transferred through the regulatory levels is currently unknown. In this thesis we have utilized high-throughput sequencing of RNA to perform genome wide analysis of transcriptional diversity and regulation across time and states. Specifically we have developed computational tools for both genome wide analysis...... used time-course data to perform an analysis of gene regulation in unprecedented details. The analysis resulted in a model where regulatory signals are deciphered first at enhancers and then subsequently in genes (Article V). This model, which is consistent across different stimuli and species...

  2. First report of cyanobacterial diversity and microcystins in a ...

    African Journals Online (AJOL)

    The cyanobacterial diversity of Sidi Boughaba, a Moroccan coastal lagoon and Ramsar site, was evaluated and its potentially toxic species were isolated and characterised. This study was the first time that cyanobacterial diversity and cyanotoxin production have been characterised in a Moroccan coastal lagoon. Samples ...

  3. Microsatellite genotyping reveals high genetic diversity but low ...

    African Journals Online (AJOL)

    JMwacharos

    2016-03-16

    Mar 16, 2016 ... diversity and (2) Investigate population structure and extent of admixture .... to estimate and partition genetic variation within and ... K between 1 and 40 and inferred its most optimal value ... populations of 0.84 ± 0.021 with the lowest mean in ..... on population stratification and the distribution of genetic.

  4. Large-Scale Spatio-Temporal Patterns of Mediterranean Cephalopod Diversity.

    Directory of Open Access Journals (Sweden)

    Stefanie Keller

    Full Text Available Species diversity is widely recognized as an important trait of ecosystems' functioning and resilience. Understanding the causes of diversity patterns and their interaction with the environmental conditions is essential in order to effectively assess and preserve existing diversity. While diversity patterns of most recurrent groups such as fish are commonly studied, other important taxa such as cephalopods have received less attention. In this work we present spatio-temporal trends of cephalopod diversity across the entire Mediterranean Sea during the last 19 years, analysing data from the annual bottom trawl survey MEDITS conducted by 5 different Mediterranean countries using standardized gears and sampling protocols. The influence of local and regional environmental variability in different Mediterranean regions is analysed applying generalized additive models, using species richness and the Shannon Wiener index as diversity descriptors. While the western basin showed a high diversity, our analyses do not support a steady eastward decrease of diversity as proposed in some previous studies. Instead, high Shannon diversity was also found in the Adriatic and Aegean Seas, and high species richness in the eastern Ionian Sea. Overall diversity did not show any consistent trend over the last two decades. Except in the Adriatic Sea, diversity showed a hump-shaped trend with depth in all regions, being highest between 200-400 m depth. Our results indicate that high Chlorophyll a concentrations and warmer temperatures seem to enhance species diversity, and the influence of these parameters is stronger for richness than for Shannon diversity.

  5. Honey bee nest thermoregulation: diversity promotes stability.

    Science.gov (United States)

    Jones, Julia C; Myerscough, Mary R; Graham, Sonia; Oldroyd, Benjamin P

    2004-07-16

    A honey bee colony is characterized by high genetic diversity among its workers, generated by high levels of multiple mating by its queen. Few clear benefits of this genetic diversity are known. Here we show that brood nest temperatures in genetically diverse colonies (i.e., those sired by several males) tend to be more stable than in genetically uniform ones (i.e., those sired by one male). One reason this increased stability arises is because genetically determined diversity in workers' temperature response thresholds modulates the hive-ventilating behavior of individual workers, preventing excessive colony-level responses to temperature fluctuations.

  6. High Production Volume Information System (HPVIS)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The High Production Volume Information System (HPVIS) provides access to select health and environmental effect information on chemicals that are manufactured in...

  7. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses

    Directory of Open Access Journals (Sweden)

    Guy Ungerechts

    2016-01-01

    Full Text Available Oncolytic viruses (OVs are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention.

  8. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses.

    Science.gov (United States)

    Ungerechts, Guy; Bossow, Sascha; Leuchs, Barbara; Holm, Per S; Rommelaere, Jean; Coffey, Matt; Coffin, Rob; Bell, John; Nettelbeck, Dirk M

    2016-01-01

    Oncolytic viruses (OVs) are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention.

  9. Unexpected high genetic diversity in small populations suggests maintenance by associative overdominance

    DEFF Research Database (Denmark)

    Schou, Mads F.; Loeschcke, Volker; Bechsgaard, Jesper

    2017-01-01

    fragmented populations. More genetic diversity was retained in areas of low recombination, suggesting that associative overdominance, driven by disfavoured homozygosity of recessive deleterious alleles, is responsible for the maintenance of genetic diversity in smaller populations. Consistent...

  10. Comparative Genomics Reveals High Genomic Diversity in the Genus Photobacterium

    DEFF Research Database (Denmark)

    Machado, Henrique; Gram, Lone

    2017-01-01

    was widespread and abundant in the genus, suggesting a role in genomic evolution. The high genetic variability and indications of genetic exchange make it difficult to elucidate genome evolutionary paths and raise the awareness of the roles of foreign DNA in the genomic evolution of environmental organisms.......Vibrionaceae is a large marine bacterial family, which can constitute up to 50% of the prokaryotic population in marine waters. Photobacterium is the second largest genus in the family and we used comparative genomics on 35 strains representing 16 of the 28 species described so far, to understand...... the genomic diversity present in the Photobacterium genus. Such understanding is important for ecophysiology studies of the genus. We used whole genome sequences to evaluate phylogenetic relationships using several analyses (16S rRNA, MLSA, fur, amino-acid usage, ANI), which allowed us to identify two...

  11. Automated Production of High Rep Rate Foam Targets

    Science.gov (United States)

    Hall, F.; Spindloe, C.; Haddock, D.; Tolley, M.; Nazarov, W.

    2016-04-01

    Manufacturing low density targets in the numbers needed for high rep rate experiments is highly challenging. This report summarises advances from manual production to semiautomated and the improvements that follow both in terms of production time and target uniformity. The production process is described and shown to be improved by the integration of an xyz robot with dispensing capabilities. Results are obtained from manual and semiautomated production runs and compared. The variance in the foam thickness is reduced significantly which should decrease experimental variation due to target parameters and could allow for whole batches to be characterised by the measurement of a few samples. The work applies to both foil backed and free standing foam targets.

  12. High genetic diversity among and within bitter manioc varieties cultivated in different soil types in Central Amazonia

    Directory of Open Access Journals (Sweden)

    Alessandro Alves-Pereira

    2017-04-01

    Full Text Available Abstract Although manioc is well adapted to nutrient-poor Oxisols of Amazonia, ethnobotanical observations show that bitter manioc is also frequently cultivated in the highly fertile soils of the floodplains and Amazonian dark earths (ADE along the middle Madeira River. Because different sets of varieties are grown in each soil type, and there are agronomic similarities between ADE and floodplain varieties, it was hypothesized that varieties grown in ADE and floodplain were more closely related to each other than either is to varieties grown in Oxisols. We tested this hypothesis evaluating the intra-varietal genetic diversity and the genetic relationships among manioc varieties commonly cultivated in Oxisols, ADE and floodplain soils. Genetic results did not agree with ethnobotanical expectation, since the relationships between varieties were variable and most individuals of varieties with the same vernacular name, but grown in ADE and floodplain, were distinct. Although the same vernacular name could not always be associated with genetic similarities, there is still a great amount of variation among the varieties. Many ecological and genetic processes may explain the high genetic diversity and differentiation found for bitter manioc varieties, but all contribute to the maintenance and amplification of genetic diversity within the manioc in Central Amazonia.

  13. Cost-effectiveness of ergonomic interventions in production

    NARCIS (Netherlands)

    Looze, M.P. de; Koningsveld, E.P.A.; Fritzsche, L.; O'Sullivan, L.; Levizzari, A.

    2008-01-01

    Ergonomic measures to reduce or eliminate the risks for developing musculoskeletal disorders, usually affects the performance at work as well, e.g. productivity or quality. The costs and benefits that can be associated with ergonomic measures are highly diverse in nature. Prior to investing in any

  14. Bacterial diversity in two Neonatal Intensive Care Units (NICUs.

    Directory of Open Access Journals (Sweden)

    Krissi M Hewitt

    Full Text Available Infants in Neonatal Intensive Care Units (NICUs are particularly susceptible to opportunistic infection. Infected infants have high mortality rates, and survivors often suffer life-long neurological disorders. The causes of many NICU infections go undiagnosed, and there is debate as to the importance of inanimate hospital environments (IHEs in the spread of infections. We used culture-independent next-generation sequencing to survey bacterial diversity in two San Diego NICUs and to track the sources of microbes in these environments. Thirty IHE samples were collected from two Level-Three NICU facilities. We extracted DNA from these samples and amplified the bacterial small subunit (16S ribosomal RNA gene sequence using 'universal' barcoded primers. The purified PCR products were pooled into a single reaction for pyrosequencing, and the data were analyzed using QIIME. On average, we detected 93+/-39 (mean +/- standard deviation bacterial genera per sample in NICU IHEs. Many of the bacterial genera included known opportunistic pathogens, and many were skin-associated (e.g., Propionibacterium. In one NICU, we also detected fecal coliform bacteria (Enterobacteriales in a high proportion of the surface samples. Comparison of these NICU-derived sequences to previously published high-throughput 16S rRNA amplicon studies of other indoor environments (offices, restrooms and healthcare facilities, as well as human- and soil-associated environments, found the majority of the NICU samples to be similar to typical building surface and air samples, with the notable exception of the IHEs which were dominated by Enterobacteriaceae. Our findings provide evidence that NICU IHEs harbor a high diversity of human-associated bacteria and demonstrate the potential utility of molecular methods for identifying and tracking bacterial diversity in NICUs.

  15. A diversity-oriented synthesis strategy enabling the combinatorial-type variation of macrocyclic peptidomimetic scaffolds.

    Science.gov (United States)

    Isidro-Llobet, Albert; Hadje Georgiou, Kathy; Galloway, Warren R J D; Giacomini, Elisa; Hansen, Mette R; Méndez-Abt, Gabriela; Tan, Yaw Sing; Carro, Laura; Sore, Hannah F; Spring, David R

    2015-04-21

    Macrocyclic peptidomimetics are associated with a broad range of biological activities. However, despite such potentially valuable properties, the macrocyclic peptidomimetic structural class is generally considered as being poorly explored within drug discovery. This has been attributed to the lack of general methods for producing collections of macrocyclic peptidomimetics with high levels of structural, and thus shape, diversity. In particular, there is a lack of scaffold diversity in current macrocyclic peptidomimetic libraries; indeed, the efficient construction of diverse molecular scaffolds presents a formidable general challenge to the synthetic chemist. Herein we describe a new, advanced strategy for the diversity-oriented synthesis (DOS) of macrocyclic peptidomimetics that enables the combinatorial variation of molecular scaffolds (core macrocyclic ring architectures). The generality and robustness of this DOS strategy is demonstrated by the step-efficient synthesis of a structurally diverse library of over 200 macrocyclic peptidomimetic compounds, each based around a distinct molecular scaffold and isolated in milligram quantities, from readily available building-blocks. To the best of our knowledge this represents an unprecedented level of scaffold diversity in a synthetically derived library of macrocyclic peptidomimetics. Cheminformatic analysis indicated that the library compounds access regions of chemical space that are distinct from those addressed by top-selling brand-name drugs and macrocyclic natural products, illustrating the value of our DOS approach to sample regions of chemical space underexploited in current drug discovery efforts. An analysis of three-dimensional molecular shapes illustrated that the DOS library has a relatively high level of shape diversity.

  16. Microbial community structure and soil pH correspond to methane production in Arctic Alaska soils.

    Science.gov (United States)

    Wagner, Robert; Zona, Donatella; Oechel, Walter; Lipson, David

    2017-08-01

    While there is no doubt that biogenic methane production in the Arctic is an important aspect of global methane emissions, the relative roles of microbial community characteristics and soil environmental conditions in controlling Arctic methane emissions remains uncertain. Here, relevant methane-cycling microbial groups were investigated at two remote Arctic sites with respect to soil potential methane production (PMP). Percent abundances of methanogens and iron-reducing bacteria correlated with increased PMP, while methanotrophs correlated with decreased PMP. Interestingly, α-diversity of the methanogens was positively correlated with PMP, while β-diversity was unrelated to PMP. The β-diversity of the entire microbial community, however, was related to PMP. Shannon diversity was a better correlate of PMP than Simpson diversity across analyses, while rarefied species richness was a weak correlate of PMP. These results demonstrate the following: first, soil pH and microbial community structure both probably control methane production in Arctic soils. Second, there may be high functional redundancy in the methanogens with regard to methane production. Third, iron-reducing bacteria co-occur with methanogens in Arctic soils, and iron-reduction-mediated effects on methanogenesis may be controlled by α- and β-diversity. And finally, species evenness and rare species abundances may be driving relationships between microbial groups, influencing Arctic methane production. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  17. Hydrogen - High pressure production and storage

    International Nuclear Information System (INIS)

    Lauretta, J.R

    2005-01-01

    The development of simple, safe and more and more efficient technologies for the production and the storage of hydrogen is necessary condition for the transition towards the economy of hydrogen.In this work the hydrogen production studies experimentally to high pressure by electrolysis of alkaline solutions without the intervention of compressing systems and its direct storage in safe containers.The made tests show that the process of electrolysis to high pressure is feasible and has better yield than to low pressure, and that is possible to solve the operation problems, with relatively simple technology.The preliminary studies and tests indicate that the system container that studied is immune to the outbreak and can have forms and very different sizes, nevertheless, to reach or to surpass the efficiency of storage of the conventional systems the investments necessary will be due to make to be able to produce aluminum alloy tubes of high resistance

  18. Diversity in Dermatology Residency Programs.

    Science.gov (United States)

    Van Voorhees, Abby S; Enos, Clinton W

    2017-10-01

    Given the change in our population to one that is more racially and ethnically diverse, the topic of diversity in dermatology residency programs has gained attention. In a field that has become highly competitive, diversity is lagging behind. What are the reasons for this? The existing diversity among medical school matriculants is reflective of the applicant pool, and although modest, there has been an increase in applications and acceptances from minority populations. However, these proportions do not carry through to the population applying to dermatology residency. Making sense of this and planning how to recruit a more diverse applicant pool will improve the quality and cultural competency of future dermatologists. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  19. DIVERSITY, STRUCTURAL PARAMETERS AND NON-TIMBER FOREST PRODUCTS IN THE FOREST RESERVE OF BONEPOUPA (DOUALA, CAMEROON

    Directory of Open Access Journals (Sweden)

    Jean Paul Kamdem

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812363In order to come up with a sustainable use of forest ecosystems in Cameroon, its vegetal diversity has been inventoried; the plant potentials and the structural parameters were studied in the forest reserve of Bonepoupa. Ten non-continuous plots of 200 m² were done and the materialization of the lines was done with a topofil put at the centre of the field with ropes at 5 m each of the topofil. In addition, ninety people were interviewed in order to know the potential use of species in this region. Up to 172 individuals with Diameter at Breast Height (DBH ≥ 5 cm divided into 27 species, 25 genera and 18 families were inventoried and the coefficient of abundance-dominance was determined. The diversity index of Shannon (H’ was H’1 = 4.17 ± 0.45 with H’1max = 4.75 and the evenness was R1 = 0.88. Taking into account herbaceous species, H’ determined by the coefficient of abundance-dominance was H’2 = 4.74 ± 0.56 with H’2max = 5.70 and the evenness  was  R2 = 0.83. The  total  basal  area  was 19.69 m2/ha and the density was 860 individuals/ha. These results indicate that herbaceous significantly modifies the value of the diversity index and that forest reserve of Bonepoupa is experiencing a problem of conservation which is due to a lack of its appropriate management. The knowledge of non-timber forest products and their use as food as well as medicinal resources by local population might be helpful for the sustainable management of resources in this forest reserve.

  20. FEATURES OF THE LOGISTICS MANAGEMENT OF PRODUCTION OF HIGH TECHNOLOGY PRODUCTS IN TURBULENCE CHANGING GLOBAL ECONOMY

    Directory of Open Access Journals (Sweden)

    Oleg M. Tolmachev

    2015-01-01

    Full Text Available The subject / topic: The level of development of any country is currently determined by the proportion of high technologies in the GDP. Logistics – the basis for efficient management of modern knowledge-intensive production. Given the adverse conditions in the global economy, greatly enhanced the relevance of the study of logistical aspects in the management of high-tech products.Subject of research: The logistics management of production of high technology products in turbulence changing global economy. In this paper we apply scientific methods: the dialectic, comparisons and analogies, analysis and synthesis, deduction and induction, abstract , logical, historical and retrospective. The purpose of this article is to identify the characteristics and problems of logistics management of production of high technology products in the countries of the Customs Union and the Eastern Partnership. Also consider the role of clusters in the formation of innovation infrastructure in the countries of the Customs Union.Results: As part of the presentation was the author of the present article the urgency of application of CALS-technologies as a tool for organization and information support for the creation, production and operation of the product at the enterprises of the national economy.Conclusions / significance: Management of enterprises in the real sector of the economy in modern conditions should be based on synergies methodological principles of market and state regulation, with increased use of methods focused on the long term. By such methods, in particular, should include the methods of logistic management of production of high technology products. The importance of these technologies has increased steadily, and in modern conditions gets a new quality content that refl ects the phased development plan targeted action to ensure that the desired state of the enterprise as a socio-economic system. This in turn points to the need to ensure that new

  1. High-precision genetic mapping of behavioral traits in the diversity outbred mouse population

    Science.gov (United States)

    Logan, R W; Robledo, R F; Recla, J M; Philip, V M; Bubier, J A; Jay, J J; Harwood, C; Wilcox, T; Gatti, D M; Bult, C J; Churchill, G A; Chesler, E J

    2013-01-01

    Historically our ability to identify genetic variants underlying complex behavioral traits in mice has been limited by low mapping resolution of conventional mouse crosses. The newly developed Diversity Outbred (DO) population promises to deliver improved resolution that will circumvent costly fine-mapping studies. The DO is derived from the same founder strains as the Collaborative Cross (CC), including three wild-derived strains. Thus the DO provides more allelic diversity and greater potential for discovery compared to crosses involving standard mouse strains. We have characterized 283 male and female DO mice using open-field, light–dark box, tail-suspension and visual-cliff avoidance tests to generate 38 behavioral measures. We identified several quantitative trait loci (QTL) for these traits with support intervals ranging from 1 to 3 Mb in size. These intervals contain relatively few genes (ranging from 5 to 96). For a majority of QTL, using the founder allelic effects together with whole genome sequence data, we could further narrow the positional candidates. Several QTL replicate previously published loci. Novel loci were also identified for anxiety- and activity-related traits. Half of the QTLs are associated with wild-derived alleles, confirming the value to behavioral genetics of added genetic diversity in the DO. In the presence of wild-alleles we sometimes observe behaviors that are qualitatively different from the expected response. Our results demonstrate that high-precision mapping of behavioral traits can be achieved with moderate numbers of DO animals, representing a significant advance in our ability to leverage the mouse as a tool for behavioral genetics PMID:23433259

  2. Assessment of genetic diversity among sixty bread wheat (Triticum ...

    African Journals Online (AJOL)

    Mwale

    2016-05-25

    May 25, 2016 ... the highest genetic diversity followed by genome B while genome D was the lowest diverse. Cluster ... and 95% of people in the developing countries eat wheat or maize in ... area for wheat production in China due to pressure from ...... hypertension in the stroke-prone spontaneously hypertensive rat. Cell.

  3. Genetic diversity in tef [Eragrostis tef (Zucc. Trotter

    Directory of Open Access Journals (Sweden)

    Kebebew eAssefa

    2015-03-01

    Full Text Available Tef [Eragrostis tef (Zucc. Trotter] is a cereal crop resilient to adverse climatic and soil conditions, and possessing desirable storage properties. Although tef provides high quality food and grows under marginal conditions unsuitable for other cereals, it is considered to be an orphan crop because it has benefited little from genetic improvement. Hence, unlike other cereals such as maize and wheat, the productivity of tef is extremely low. In spite of the low productivity, tef is widely cultivated by over six million small-scale farmers in Ethiopia where it is annually grown on more than three million hectares of land, accounting for over 30% of the total cereal acreage. Tef, a tetraploid with 40 chromosomes (2n=4x=40, belongs to the Family Poaceae and, together with finger millet (Eleusine coracana Gaertn, to the Subfamily Chloridoideae. It was believed to have originated in Ethiopia. There are about 350 Eragrostis species of which E. tef is the only species cultivated for human consumption. At the present time, the gene bank in Ethiopia holds over five thousand tef accessions collected from geographical regions diverse in terms of climate and elevation. These germplasm accessions appear to have huge variability with regard to key agronomic and nutritional traits. In order to properly utilize the variability in developing new tef cultivars, various techniques have been implemented to catalog the extent and unravel the patterns of genetic diversity. In this review, we show some recent initiatives investigating the diversity of tef using genomics, transcriptomics and proteomics and discuss the prospect of these efforts in providing molecular resources that can aid modern tef breeding.

  4. Product design - Molecules, devices, functional products, and formulated products

    DEFF Research Database (Denmark)

    Gani, Rafiqul; Ng, Ka M.

    2015-01-01

    Chemical product design is a multidisciplinary and diverse subject. This article provides an overview of product design while focusing on product conceptualization. Four product types are considered - molecular products, formulated products, devices and functional products. For molecular products......, computer-aided design tools are used to predict the physicochemical properties of single molecules and blends. For formulated products, an integrated experiment-modeling approach is used to generate the formula with the specified product attributes. For devices and functional products, conceptual product...... design is carried out by modeling the product based on thermodynamics, kinetics and transport processes, by performing experiments, and by decision making based on rule-based methods The results are product specifications in terms of the type of ingredients, composition, and the structure, form, shape...

  5. Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Ranya A. Amer

    2015-01-01

    Full Text Available Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt. Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed.

  6. Bacterial Diversity and Bioremediation Potential of the Highly Contaminated Marine Sediments at El-Max District (Egypt, Mediterranean Sea)

    Science.gov (United States)

    Amer, Ranya A.; El Gendi, Hamada M.; Goda, Doaa A.; Corsini, Anna; Cavalca, Lucia; Fusi, Marco; Daffonchio, Daniele; Abdel-Fattah, Yasser R.

    2015-01-01

    Coastal environments worldwide are threatened by the effects of pollution, a risk particularly high in semienclosed basins like the Mediterranean Sea that is poorly studied from bioremediation potential perspective especially in the Southern coast. Here, we investigated the physical, chemical, and microbiological features of hydrocarbon and heavy metals contaminated sediments collected at El-Max bay (Egypt). Molecular and statistical approaches assessing the structure of the sediment-dwelling bacterial communities showed correlations between the composition of bacterial assemblages and the associated environmental parameters. Fifty strains were isolated on mineral media supplemented by 1% crude oil and identified as a diverse range of hydrocarbon-degrading bacteria involved in different successional stages of biodegradation. We screened the collection for biotechnological potential studying biosurfactant production, biofilm formation, and the capability to utilize different hydrocarbons. Some strains were able to grow on multiple hydrocarbons as unique carbon source and presented biosurfactant-like activities and/or capacity to form biofilm and owned genes involved in different detoxification/degradation processes. El-Max sediments represent a promising reservoir of novel bacterial strains adapted to high hydrocarbon contamination loads. The potential of the strains for exploitation for in situ intervention to combat pollution in coastal areas is discussed. PMID:26273661

  7. Effects of shearing on biogas production and microbial community structure during anaerobic digestion with recuperative thickening.

    Science.gov (United States)

    Yang, Shufan; Phan, Hop V; Bustamante, Heriberto; Guo, Wenshan; Ngo, Hao H; Nghiem, Long D

    2017-06-01

    Recuperative thickening can intensify anaerobic digestion to produce more biogas and potentially reduce biosolids odour. This study elucidates the effects of sludge shearing during the thickening process on the microbial community structure and its effect on biogas production. Medium shearing resulted in approximately 15% increase in biogas production. By contrast, excessive or high shearing led to a marked decrease in biogas production, possibly due to sludge disintegration and cell lysis. Microbial analysis using 16S rRNA gene amplicon sequencing showed that medium shearing increased the evenness and diversity of the microbial community in the anaerobic digester, which is consistent with the observed improved biogas production. By contrast, microbial diversity decreased under either excessive shearing or high shearing condition. In good agreement with the observed decrease in biogas production, the abundance of Bacteroidales and Syntrophobaterales (which are responsible for hydrolysis and acetogenesis) decreased due to high shearing during recuperative thickening. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  8. Scaffold Diversity from N-Acyliminium Ions

    DEFF Research Database (Denmark)

    Wu, Peng; Nielsen, Thomas E

    2017-01-01

    N-Acyliminium ions are powerful reactive species for the formation of carbon-carbon and carbon-heteroatom bonds. Strategies relying on intramolecular reactions of N-acyliminium intermediates, also referred to as N-acyliminium ion cyclization reactions, have been employed for the construction...... of structurally diverse scaffolds, ranging from simple bicyclic skeletons to complex polycyclic systems and natural-product-like compounds. This review aims to provide an overview of cyclization reactions of N-acyliminium ions derived from various precursors for the assembly of structurally diverse scaffolds...

  9. Improving industrial yeast strains: exploiting natural and artificial diversity

    Science.gov (United States)

    Steensels, Jan; Snoek, Tim; Meersman, Esther; Nicolino, Martina Picca; Voordeckers, Karin; Verstrepen, Kevin J

    2014-01-01

    Yeasts have been used for thousands of years to make fermented foods and beverages, such as beer, wine, sake, and bread. However, the choice for a particular yeast strain or species for a specific industrial application is often based on historical, rather than scientific grounds. Moreover, new biotechnological yeast applications, such as the production of second-generation biofuels, confront yeast with environments and challenges that differ from those encountered in traditional food fermentations. Together, this implies that there are interesting opportunities to isolate or generate yeast variants that perform better than the currently used strains. Here, we discuss the different strategies of strain selection and improvement available for both conventional and nonconventional yeasts. Exploiting the existing natural diversity and using techniques such as mutagenesis, protoplast fusion, breeding, genome shuffling and directed evolution to generate artificial diversity, or the use of genetic modification strategies to alter traits in a more targeted way, have led to the selection of superior industrial yeasts. Furthermore, recent technological advances allowed the development of high-throughput techniques, such as ‘global transcription machinery engineering’ (gTME), to induce genetic variation, providing a new source of yeast genetic diversity. PMID:24724938

  10. The California Biomass Crop Adoption Model estimates biofuel feedstock crop production across diverse agro-ecological zones within the state, under different future climates

    Science.gov (United States)

    Kaffka, S.; Jenner, M.; Bucaram, S.; George, N.

    2012-12-01

    Both regulators and businesses need realistic estimates for the potential production of biomass feedstocks for biofuels and bioproducts. This includes the need to understand how climate change will affect mid-tem and longer-term crop performance and relative advantage. The California Biomass Crop Adoption Model is a partial mathematical programming optimization model that estimates the profit level needed for new crop adoption, and the crop(s) displaced when a biomass feedstock crop is added to the state's diverse set of cropping systems, in diverse regions of the state. Both yield and crop price, as elements of profit, can be varied. Crop adoption is tested against current farmer preferences derived from analysis of 10 years crop production data for all crops produced in California, collected by the California Department of Pesticide Regulation. Analysis of this extensive data set resulted in 45 distinctive, representative farming systems distributed across the state's diverse agro-ecological regions. Estimated yields and water use are derived from field trials combined with crop simulation, reported elsewhere. Crop simulation is carried out under different weather and climate assumptions. Besides crop adoption and displacement, crop resource use is also accounted, derived from partial budgets used for each crop's cost of production. Systematically increasing biofuel crop price identified areas of the state where different types of crops were most likely to be adopted. Oilseed crops like canola that can be used for biodiesel production had the greatest potential to be grown in the Sacramento Valley and other northern regions, while sugar beets (for ethanol) had the greatest potential in the northern San Joaquin Valley region, and sweet sorghum in the southern San Joaquin Valley. Up to approximately 10% of existing annual cropland in California was available for new crop adoption. New crops are adopted if the entire cropping system becomes more profitable. In

  11. The HARNESS Workbench: Unified and Adaptive Access to Diverse HPC Platforms

    Energy Technology Data Exchange (ETDEWEB)

    Sunderam, Vaidy S.

    2012-03-20

    The primary goal of the Harness WorkBench (HWB) project is to investigate innovative software environments that will help enhance the overall productivity of applications science on diverse HPC platforms. Two complementary frameworks were designed: one, a virtualized command toolkit for application building, deployment, and execution, that provides a common view across diverse HPC systems, in particular the DOE leadership computing platforms (Cray, IBM, SGI, and clusters); and two, a unified runtime environment that consolidates access to runtime services via an adaptive framework for execution-time and post processing activities. A prototype of the first was developed based on the concept of a 'system-call virtual machine' (SCVM), to enhance portability of the HPC application deployment process across heterogeneous high-end machines. The SCVM approach to portable builds is based on the insertion of toolkit-interpretable directives into original application build scripts. Modifications resulting from these directives preserve the semantics of the original build instruction flow. The execution of the build script is controlled by our toolkit that intercepts build script commands in a manner transparent to the end-user. We have applied this approach to a scientific production code (Gamess-US) on the Cray-XT5 machine. The second facet, termed Unibus, aims to facilitate provisioning and aggregation of multifaceted resources from resource providers and end-users perspectives. To achieve that, Unibus proposes a Capability Model and mediators (resource drivers) to virtualize access to diverse resources, and soft and successive conditioning to enable automatic and user-transparent resource provisioning. A proof of concept implementation has demonstrated the viability of this approach on high end machines, grid systems and computing clouds.

  12. TX-RX isolation method based on polarization diversity, spatial diversity and TX beamforming

    DEFF Research Database (Denmark)

    Foroozanfard, Ehsan; Carvalho, Elisabeth De; Pedersen, Gert F.

    2016-01-01

    In this paper, the feasibility of an antenna isolation technique based on null-steer beamforming, polarization diversity and spatial diversity is investigated. The proposed system consists of six patch antennas which are fed by a feeding network to obtain a null-steer beamformer. To achieve spatial...... diversity, antenna elements are located on two layers, facing in a different direction. Moreover, the antenna elements in two layers use different polarization. The measured results of the antenna system present a high TX-RX isolation in the order of 70 dB which shows the feasibility of such a system...

  13. Microbial diversity of a high salinity oil field

    International Nuclear Information System (INIS)

    Neria, I.; Gales, G.; Alazard, D.; Ollivier, B.; Borgomano, J.; Joulian, C.

    2009-01-01

    This work is a preliminary study to investigate the microbial diversity of an onshore oil field. It aim to compare results obtained from molecular methods, physicochemical analyses and cultivation. A core of 1150 m depth sediments ( in situ T=45 degree centigrade) was collected and immediately frozen with liquid nitrogen prior to further investigation. Macroscopic and Scanning Electron Microscopy analyses were performed. (Author)

  14. Repeated burning of eastern tallgrass prairie increases richness and diversity, stabilizing late successional vegetation.

    Science.gov (United States)

    Bowles, Marlin L; Jones, Michael D

    2013-03-01

    Understanding temporal effects of fire frequency on plant species diversity and vegetation structure is critical for managing tallgrass prairie (TGP), which occupies a mid-continental longitudinal precipitation and productivity gradient. Eastern TGP has contributed little information toward understanding whether vegetation-fire interactions are uniform or change across this biome. We resampled 34 fire-managed mid- and late-successional ungrazed TGP remnants occurring across a dry to wet-mesic moisture gradient in the Chicago region of Illinois, USA. We compared hypotheses that burning acts either as a stabilizing force or causes change in diversity and structure, depending upon fire frequency and successional stage. Based on western TGP, we expected a unimodal species richness distribution across a cover-productivity gradient, variable functional group responses to fire frequency, and a negative relationship between fire frequency and species richness. Species diversity was unimodal across the cover gradient and was more strongly humpbacked in stands with greater fire frequency. In support of a stabilizing hypothesis, temporal similarity of late-successional vegetation had a logarithmic relationship with increasing fire frequency, while richness and evenness remained stable. Temporal similarity within mid-successional stands was not correlated with fire frequency, while richness increased and evenness decreased over time. Functional group responses to fire frequency were variable. Summer forb richness increased under high fire frequency, while C4 grasses, spring forbs, and nitrogen-fixing species decreased with fire exclusion. On mesic and wet-mesic sites, vegetation structure measured by the ratio of woody to graminoid species was negatively correlated with abundance of forbs and with fire frequency. Our findings that species richness responds unimodally to an environmental-productivity gradient, and that fire exclusion increases woody vegetation and leads to loss

  15. Genetic diversity study of common bean ( Phaseolus vulgaris L ...

    African Journals Online (AJOL)

    In PCoA, majority individuals of Metekel (L) tended to form separate group. The result of the study confirmed the presence of genetic diversity that can be exploited to improve the productivity. This calls for a conserted efforts in the collection, conservation and sustainable use of P. vulgaris. Keywords: Genetic diversity, ISSR, ...

  16. Race and Academic Achievement in Racially Diverse High Schools: Opportunity and Stratification.

    Science.gov (United States)

    Muller, Chandra; Riegle-Crumb, Catherine; Schiller, Kathryn S; Wilkinson, Lindsey; Frank, Kenneth A

    2010-04-01

    BACKGROUND/CONTEXT: Brown v Board of Education fundamentally changed our nation's schools, yet we know surprisingly little about how and whether they provide equality of educational opportunity. Although substantial evidence suggests that African American and Latino students who attend these schools face fewer learning opportunities than their White counterparts, until now, it has been impossible to examine this using a representative sample because of lack of data. PURPOSE/OBJECTIVE/RESEARCH QUESTION/FOCUS OF STUDY: This study uses newly available data to investigate whether racially diverse high schools offer equality of educational opportunity to students from different racial and ethnic groups. This is examined by measuring the relative representation of minority students in advanced math classes at the beginning of high school and estimating whether and how this opportunity structure limits the level of achievement attained by African American and Latino students by the end of high school. SETTING: This study uses data from the Adolescent Health and Academic Achievement Study (AHAA) and its partner study, the National Longitudinal Study of Adolescent Health (Add Health), a stratified, nationally representative study of students in U.S. high schools first surveyed in 1994-1995. POPULATION/PARTICIPANTS/SUBJECTS: Two samples of racially diverse high schools were used in the analysis: one with African Americans, Whites, and Asians (26 schools with 3,149 students), and the other with Latinos, Whites, and Asians (22 schools with 2,775 students). RESEARCH DESIGN: Quantitative analyses first assess how high schools vary in the extent to which minority students are underrepresented in advanced sophomore math classes. Hierarchical multilevel modeling is then used to estimate whether racial-ethnic differences in representation in advanced math have an impact on African American and Latino students' achievement by the end of high school, relative to the Whites and Asians

  17. Pricing Policy and Strategies for Consumer High-Tech Products

    Directory of Open Access Journals (Sweden)

    Dovleac, L.

    2014-06-01

    Full Text Available This paper highlights the complex process of price setting for consumer high-tech products. These prices are highly influenced by some external factors from the economic and social environment. The main objective of this paper is to establish the most effective pricing policies and strategies used by high-tech companies of various sizes. Decisions about price fixing for consumer high-technology products are largely influenced by consumer behaviour, too.

  18. Production processes at extremely high energies

    CERN Document Server

    Gastmans, R; Wu, Tai Tsun

    2013-01-01

    The production processes are identified that contribute to the rise of the total cross section in proton-proton scattering at extremely high energies, s->~. At such energies, the scattering can be described by a black disk (completely absorptive) with a radius expanding logarithmically with energy surrounded by a gray fringe (partially absorptive). For the leading term of (lns)^2 in the increasing total cross section, the gray fringe is neglected, and geometrical optics is generalized to production processes. It is known that half of the rise in the total cross section is due to elastic scattering. The other half is found to originate from the production of jets with relatively small momenta in the center-of-mass system.

  19. The Effect of Mutual Coupling on a High Altitude Platform Diversity System Using Compact Antenna Arrays

    Directory of Open Access Journals (Sweden)

    Tommy Hult

    2010-01-01

    Full Text Available We analyze the destructive effects of mutual coupling and spatial correlation between the separate antenna elements on a combined diversity system consisting of multiple HAPs (High-Altitude Platforms employing various compact MIMO (Multiple-Input Multiple-Output antenna array configurations, in order to enhance the mutual information in HAP communication links. In addition, we assess the influence of the separation angle between HAPs on system performance, and determine the optimal separation angles that maximize the total mutual information of the system for various compact MIMO antennas. Simulation results show that although the mutual information is degraded by mutual coupling and spatial correlation, the proposed HAP diversity system still provides better performance compared to a nondiversity system for all tested scenarios.

  20. Nursing and health sciences workforce diversity research using PhotoVoice: a college and high school student participatory project.

    Science.gov (United States)

    Benavides-Vaello, Sandra; Katz, Janet R; Peterson, Jeffery Chaichana; Allen, Carol B; Paul, Robbie; Charette-Bluff, Andrea Lelana; Morris, Phyllis

    2014-04-01

    This participatory study used PhotoVoice and qualitative description to (a) mentor baccalaureate nursing and college students in workforce diversity research; (b) explore barriers and facilitators encountered by rural American Indian, Hispanic, and other high school students when attending college and pursuing careers in nursing or the health sciences; and (c) model a process of social action to help existing and future students. Baccalaureate nursing and graduate students participated in all stages of research, including dissemination. Five themes emerged from analysis of PhotoVoice data: (a) being afraid; (b) believing; (c) taking small steps; (d) facing fears; and (e) using support systems. Findings underscore the importance of helping students participate in efforts to increase work-force diversity through research. Increasing nursing and health sciences workforce diversity may require strategies developed within and tailored to specific cultures and communities. Copyright 2014, SLACK Incorporated.

  1. Marine reserves help preserve genetic diversity after impacts derived from climate variability: Lessons from the pink abalone in Baja California

    Directory of Open Access Journals (Sweden)

    Adrián Munguía-Vega

    2015-07-01

    Full Text Available Genetic diversity is crucial for the adaptation of exploited species like the pink abalone (Haliotis corrugata, faced with threats from climate change, overfishing and impacts associated with aquaculture production. While marine reserves are commonly used to mitigate risks to marine populations, the duration, size, location and larval connectivity needed for a reserve to help conserve genetic resources is still poorly understood. Here, we examine the effects of fishing, reserves, and restocking on the genetic diversity of 10 populations from central Baja California, Mexico, and Southern California, USA. We demonstrate that each population shows characteristic genetic signatures according to recent management decisions. We found high allelic diversity, particularly rare alleles, a larger effective population size and a lack of a recent genetic bottleneck in pink abalones within a small (0.8 km2, recently established (5 years reserve in Baja California, compared to other fished sites after a climatic bottleneck. Higher diversity may result from the presence of older animals in the reserve. Due to its location, the reserve may also act as an important hub connecting distant populations via larval dispersal. In contrast, a population from California showed genetic isolation, loss of allelic diversity and high relatedness, consistent with the collapse of fisheries in the 1990s and their lack of recovery thereafter. In addition, a fished area in Baja California with a history of restocking for over a decade showed an increase in frequency of related individuals and high genetic differentiation from nearby sites that were consistent with the production of larvae from a few adults in the laboratory. A network of strategically placed small marine reserves that considers ocean circulation patterns could help to maintain genetic diversity and connectivity of exploited populations.

  2. Human Diversity in a Cell Surface Receptor that Inhibits Autophagy.

    Science.gov (United States)

    Chaudhary, Anu; Leite, Mara; Kulasekara, Bridget R; Altura, Melissa A; Ogahara, Cassandra; Weiss, Eli; Fu, Wenqing; Blanc, Marie-Pierre; O'Keeffe, Michael; Terhorst, Cox; Akey, Joshua M; Miller, Samuel I

    2016-07-25

    Mutations in genes encoding autophagy proteins have been associated with human autoimmune diseases, suggesting that diversity in autophagy responses could be associated with disease susceptibility or severity. A cellular genome-wide association study (GWAS) screen was performed to explore normal human diversity in responses to rapamycin, a microbial product that induces autophagy. Cells from several human populations demonstrated variability in expression of a cell surface receptor, CD244 (SlamF4, 2B4), that correlated with changes in rapamycin-induced autophagy. High expression of CD244 and receptor activation with its endogenous ligand CD48 inhibited starvation- and rapamycin-induced autophagy by promoting association of CD244 with the autophagy complex proteins Vps34 and Beclin-1. The association of CD244 with this complex reduced Vps34 lipid kinase activity. Lack of CD244 is associated with auto-antibody production in mice, and lower expression of human CD244 has previously been implicated in severity of human rheumatoid arthritis and systemic lupus erythematosus, indicating that increased autophagy as a result of low levels of CD244 may alter disease outcomes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Hearing diversity in moths confronting a neotropical bat assemblage.

    Science.gov (United States)

    Cobo-Cuan, Ariadna; Kössl, Manfred; Mora, Emanuel C

    2017-09-01

    The tympanal ear is an evolutionary acquisition which helps moths survive predation from bats. The greater diversity of bats and echolocation strategies in the Neotropics compared with temperate zones would be expected to impose different sensory requirements on the neotropical moths. However, even given some variability among moth assemblages, the frequencies of best hearing of moths from different climate zones studied to date have been roughly the same: between 20 and 60 kHz. We have analyzed the auditory characteristics of tympanate moths from Cuba, a neotropical island with high levels of bat diversity and a high incidence of echolocation frequencies above those commonly at the upper limit of moths' hearing sensitivity. Moths of the superfamilies Noctuoidea, Geometroidea and Pyraloidea were examined. Audiograms were determined by non-invasively measuring distortion-product otoacoustic emissions. We also quantified the frequency spectrum of the echolocation sounds to which this moth community is exposed. The hearing ranges of moths in our study showed best frequencies between 36 and 94 kHz. High sensitivity to frequencies above 50 kHz suggests that the auditory sensitivity of moths is suited to the sounds used by sympatric echolocating bat fauna. Biodiversity characterizes predators and prey in the Neotropics, but the bat-moth acoustic interaction keeps spectrally matched.

  4. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    International Nuclear Information System (INIS)

    McPhee, William S.

    2001-01-01

    The Department of Energy (DOE) needs improved technologies to decontaminate large areas of both concrete and steel surfaces. The technology should have high operational efficiency, minimize exposures to workers, and produce low levels of secondary waste. In order to meet the DOE's needs, an applied research and development project for the improvement of a current decontamination technology, Vacuum Blasting, is proposed. The objective of this project is to improve the productivity and lower the expense of the existing vacuum blasting technology which has been widely used in DOE sites for removing radioactive contamination, PCBs, and lead-based paint. The proposed work would increase the productivity rate and provide safe and cost-effective decontamination of the DOE sites

  5. Stress Tolerance Variations in Saccharomyces cerevisiae Strains from Diverse Ecological Sources and Geographical Locations.

    Directory of Open Access Journals (Sweden)

    Yan-Lin Zheng

    Full Text Available The budding yeast Saccharomyces cerevisiae is a platform organism for bioethanol production from various feedstocks and robust strains are desirable for efficient fermentation because yeast cells inevitably encounter stressors during the process. Recently, diverse S. cerevisiae lineages were identified, which provided novel resources for understanding stress tolerance variations and related shaping factors in the yeast. This study characterized the tolerance of diverse S. cerevisiae strains to the stressors of high ethanol concentrations, temperature shocks, and osmotic stress. The results showed that the isolates from human-associated environments overall presented a higher level of stress tolerance compared with those from forests spared anthropogenic influences. Statistical analyses indicated that the variations of stress tolerance were significantly correlated with both ecological sources and geographical locations of the strains. This study provides guidelines for selection of robust S. cerevisiae strains for bioethanol production from nature.

  6. Metagenomic analysis revealed highly diverse microbial arsenic metabolism genes in paddy soils with low-arsenic contents

    International Nuclear Information System (INIS)

    Xiao, Ke-Qing; Li, Li-Guan; Ma, Li-Ping; Zhang, Si-Yu; Bao, Peng; Zhang, Tong; Zhu, Yong-Guan

    2016-01-01

    Microbe-mediated arsenic (As) metabolism plays a critical role in global As cycle, and As metabolism involves different types of genes encoding proteins facilitating its biotransformation and transportation processes. Here, we used metagenomic analysis based on high-throughput sequencing and constructed As metabolism protein databases to analyze As metabolism genes in five paddy soils with low-As contents. The results showed that highly diverse As metabolism genes were present in these paddy soils, with varied abundances and distribution for different types and subtypes of these genes. Arsenate reduction genes (ars) dominated in all soil samples, and significant correlation existed between the abundance of arr (arsenate respiration), aio (arsenite oxidation), and arsM (arsenite methylation) genes, indicating the co-existence and close-relation of different As resistance systems of microbes in wetland environments similar to these paddy soils after long-term evolution. Among all soil parameters, pH was an important factor controlling the distribution of As metabolism gene in five paddy soils (p = 0.018). To the best of our knowledge, this is the first study using high-throughput sequencing and metagenomics approach in characterizing As metabolism genes in the five paddy soil, showing their great potential in As biotransformation, and therefore in mitigating arsenic risk to humans. - Highlights: • Use metagenomics to analyze As metabolism genes in paddy soils with low-As content. • These genes were ubiquitous, abundant, and associated with diverse microbes. • pH as an important factor controlling their distribution in paddy soil. • Imply combinational effect of evolution and selection on As metabolism genes. - Metagenomics was used to analyze As metabolism genes in paddy soils with low-As contents. These genes were ubiquitous, abundant, and associated with diverse microbes.

  7. Sustainability of mega water diversion projects: Experience and lessons from China.

    Science.gov (United States)

    Yu, Min; Wang, Chaoran; Liu, Yi; Olsson, Gustaf; Wang, Chunyan

    2018-04-01

    Water availability and water demand are not evenly distributed in time and space. Many mega water diversion projects have been launched to alleviate water shortages in China. This paper analyzes the temporal and spatial features of 59 mega water diversion projects in China using statistical analysis. The relationship between nine major basins is measured using a network analysis method, and the associated economic, environmental and social impacts are explored using an impact analysis method. The study finds the development of water diversion has experienced four stages in China, from a starting period through to a period of high-speed development. Both the length of water diversion channels and the amount of transferred water have increased significantly in the past 50years. As of 2015, over 100billionm 3 of water was transferred in China through 16,000km in channels. These projects reached over half of China's provinces. The Yangtze River Basin is now the largest source of transferred water. Through inter-basin water diversion, China gains the opportunity to increase Gross Domestic Product by 4%. However, the construction costs exceed 150 billion US dollars, larger than in any other country. The average cost per unit of transferred water has increased with time and scale but decreased from western to eastern China. Furthermore, annual total energy consumption for pumping exceeded 50billionkilowatt-hours and the related greenhouse gas emissions are estimated to be 48milliontons. It is worth noting that ecological problems caused by water diversion affect the Han River and Yellow River Basins. Over 500 thousand people have been relocated away from their homes due to water diversion. To improve the sustainability of water diversion, four kinds of innovative measures have been provided for decision makers: national diversion guidelines, integrated water basin management, economic incentives and ex-post evaluation. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Diversity of Communications, Diversity of Communities: Strategic Choices for Maximum Engagement

    Science.gov (United States)

    Bartel, B. A.; Unger, M.

    2017-12-01

    One of the challenges around the edges of scientific research is finding ways to effectively communicate about that research beyond the confines of a highly specialized scientific community. While peer-review, publication, and scientific conferences and workshops allow scientists to effectively share their research with colleagues in their field, these exclusive communications do little to reach outside of those circles. Amid increasing requirements to demonstrate the value of research, and threats to funding of both basic and applied research, it becomes increasingly important for scientists and those in fields related to science communications to find, and continually update, tools for effectively reaching broad audiences. Drawing on experiences in science communications from various entities including the National Center for Atmospheric Research, UNAVCO, and the National Snow and Ice Data Center, we will present lessons learned that can be applied to communications endeavors on all scales, from individual researchers to large organizations. We will explore various channels, messengers, messages, and methods we have used effectively to reach diverse and broad audiences. In thinking about science communications, it is critical to not only understand the audiences we are attempting to reach, but also to meet them in the spaces they frequent. Therefore, we have found value in diversifying communications strategies in order to engage with diverse demographics, using the means most likely to connect with each. Multiple communications channels and strategies reach different age groups, speakers of different languages, and audiences of varying knowledge, experience, age, and interest levels. For example, on social media, Instagram reaches a young demographic and Pinterest is an ideal way to reach educators. Diversity in communications products and channels also addresses varying learning styles and moods, offering opportunities for explanations (e.g, videos

  9. North-South differentiation and a region of high diversity in European wolves (Canis lupus.

    Directory of Open Access Journals (Sweden)

    Astrid V Stronen

    Full Text Available European wolves (Canis lupus show population genetic structure in the absence of geographic barriers, and across relatively short distances for this highly mobile species. Additional information on the location of and divergence between population clusters is required, particularly because wolves are currently recolonizing parts of Europe. We evaluated genetic structure in 177 wolves from 11 countries using over 67K single nucleotide polymorphism (SNP loci. The results supported previous findings of an isolated Italian population with lower genetic diversity than that observed across other areas of Europe. Wolves from the remaining countries were primarily structured in a north-south axis, with Croatia, Bulgaria, and Greece (Dinaric-Balkan differentiated from northcentral wolves that included individuals from Finland, Latvia, Belarus, Poland and Russia. Carpathian Mountain wolves in central Europe had genotypes intermediate between those identified in northcentral Europe and the Dinaric-Balkan cluster. Overall, individual genotypes from northcentral Europe suggested high levels of admixture. We observed high diversity within Belarus, with wolves from western and northern Belarus representing the two most differentiated groups within northcentral Europe. Our results support the presence of at least three major clusters (Italy, Carpathians, Dinaric-Balkan in southern and central Europe. Individuals from Croatia also appeared differentiated from wolves in Greece and Bulgaria. Expansion from glacial refugia, adaptation to local environments, and human-related factors such as landscape fragmentation and frequent killing of wolves in some areas may have contributed to the observed patterns. Our findings can help inform conservation management of these apex predators and the ecosystems of which they are part.

  10. Genetic diversity of sesame (sesamum indicum L.) germplasm from Pakistan using RAPD markers

    Energy Technology Data Exchange (ETDEWEB)

    Akbar, F; Rabbani, M A; Masood, M S; Shinwari, Z.K., E-mail: shinwari@qau.edu.p

    2011-08-15

    Genetic diversity among 20 sesame (Sesamum indicum L.) accessions was examined at DNA level by means of random amplified polymorphic DNA (RAPD) analysis. Ten primers used produced a total of 93 RAPD fragments, of which 70 (75%) were polymorphic. Each primer generated 5 to 17 amplified fragments with an average of 9.3 bands per primer. Based on pair-wise comparisons of RAPD amplification products, Nei and Li's similarity coefficients were computed to assess the associations among the accessions. Pair-wise similarity indices varied from 0.65 to 0.91. A UPGMA cluster analysis based on these genetic similarities located most of the accessions far apart from one another, showing a high level of polymorphism. Genetically, all the genotypes were classified into two major groups and six subgroups or clusters. A single accession (22243) was relatively distinct from rest of the accessions and created independent cluster. In conclusion, even with the use of a limited set of primers, RAPD technique revealed a high level of genetic variation among sesame accessions collected from diverse ecologies of Pakistan. This high level of genetic diversity among the genotypes suggested that RAPD technique is valuable for sesame systematic, and can be helpful for the upholding of germplasm banks and the competent choice of parents in breeding programs. (author)

  11. Genetic diversity of sesame (sesamum indicum L.) germplasm from Pakistan using RAPD markers

    International Nuclear Information System (INIS)

    Akbar, F; Rabbani, M.A.; Masood, M.S.; Shinwari, Z.K.

    2011-01-01

    Genetic diversity among 20 sesame (Sesamum indicum L.) accessions was examined at DNA level by means of random amplified polymorphic DNA (RAPD) analysis. Ten primers used produced a total of 93 RAPD fragments, of which 70 (75%) were polymorphic. Each primer generated 5 to 17 amplified fragments with an average of 9.3 bands per primer. Based on pair-wise comparisons of RAPD amplification products, Nei and Li's similarity coefficients were computed to assess the associations among the accessions. Pair-wise similarity indices varied from 0.65 to 0.91. A UPGMA cluster analysis based on these genetic similarities located most of the accessions far apart from one another, showing a high level of polymorphism. Genetically, all the genotypes were classified into two major groups and six subgroups or clusters. A single accession (22243) was relatively distinct from rest of the accessions and created independent cluster. In conclusion, even with the use of a limited set of primers, RAPD technique revealed a high level of genetic variation among sesame accessions collected from diverse ecologies of Pakistan. This high level of genetic diversity among the genotypes suggested that RAPD technique is valuable for sesame systematic, and can be helpful for the upholding of germplasm banks and the competent choice of parents in breeding programs. (author)

  12. The Methodical Instrumentarium for Analytical Monitoring of Markets for High-Tech Products

    Directory of Open Access Journals (Sweden)

    Mikaelian Suren G.

    2017-10-01

    Full Text Available The article is aimed at clarifying the essential characteristics of high-tech products and specifying the features of analytical monitoring of markets for high-tech products. The conceptual approaches to interpretation of the essence of high-tech products as a basic concept in the categorical apparatus for researching the systemic and complex processes of technological development have been clarified. The most efficient instruments for assessing innovation processes in the high-tech sphere have been systematized. The methodical instrumentarium for analytical monitoring of the markets for high-tech products has been clarified. The terminology of a high-tech product has been clarified in order to formulate the methodical instrumentarium for analytical monitoring of market for high-tech products. It has been determined that «high-tech products» are the original basic concept in the categorical apparatus for researching the systemic and complex processes of the high-tech market that needs to be concretized. Conceptual approaches to the essence of high-tech products have been systematized.

  13. Spillovers from immigrant diversity in cities

    OpenAIRE

    Kemeny, Thomas; Cooke, Abigail

    2018-01-01

    Theory and evidence suggest that people born in different countries complement each other in the labor market. Immigrant diversity could augment productivity by enabling the combination of different skills, ideas and perspectives, resulting in greater productivity. Using matched employer-employee data for the U.S., this paper evaluates this claim, and makes empirical and conceptual contributions to prior work. It addresses potential bias from unobserved heterogeneity among individuals, work...

  14. High amino acid diversity and positive selection at a putative coral immunity gene (tachylectin-2

    Directory of Open Access Journals (Sweden)

    Hellberg Michael E

    2010-05-01

    Full Text Available Abstract Background Genes involved in immune functions, including pathogen recognition and the activation of innate defense pathways, are among the most genetically variable known, and the proteins that they encode are often characterized by high rates of amino acid substitutions, a hallmark of positive selection. The high levels of variation characteristic of immunity genes make them useful tools for conservation genetics. To date, highly variable immunity genes have yet to be found in corals, keystone organisms of the world's most diverse marine ecosystem, the coral reef. Here, we examine variation in and selection on a putative innate immunity gene from Oculina, a coral genus previously used as a model for studies of coral disease and bleaching. Results In a survey of 244 Oculina alleles, we find high nonsynonymous variation and a signature of positive selection, consistent with a putative role in immunity. Using computational protein structure prediction, we generate a structural model of the Oculina protein that closely matches the known structure of tachylectin-2 from the Japanese horseshoe crab (Tachypleus tridentatus, a protein with demonstrated function in microbial recognition and agglutination. We also demonstrate that at least three other genera of anthozoan cnidarians (Acropora, Montastrea and Nematostella possess proteins structurally similar to tachylectin-2. Conclusions Taken together, the evidence of high amino acid diversity, positive selection and structural correspondence to the horseshoe crab tachylectin-2 suggests that this protein is 1 part of Oculina's innate immunity repertoire, and 2 evolving adaptively, possibly under selective pressure from coral-associated microorganisms. Tachylectin-2 may serve as a candidate locus to screen coral populations for their capacity to respond adaptively to future environmental change.

  15. Diversity and functions of bacterial community in drinking water biofilms revealed by high-throughput sequencing

    Science.gov (United States)

    Chao, Yuanqing; Mao, Yanping; Wang, Zhiping; Zhang, Tong

    2015-06-01

    The development of biofilms in drinking water (DW) systems may cause various problems to water quality. To investigate the community structure of biofilms on different pipe materials and the global/specific metabolic functions of DW biofilms, PCR-based 454 pyrosequencing data for 16S rRNA genes and Illumina metagenomic data were generated and analysed. Considerable differences in bacterial diversity and taxonomic structure were identified between biofilms formed on stainless steel and biofilms formed on plastics, indicating that the metallic materials facilitate the formation of higher diversity biofilms. Moreover, variations in several dominant genera were observed during biofilm formation. Based on PCA analysis, the global functions in the DW biofilms were similar to other DW metagenomes. Beyond the global functions, the occurrences and abundances of specific protective genes involved in the glutathione metabolism, the SoxRS system, the OxyR system, RpoS regulated genes, and the production/degradation of extracellular polymeric substances were also evaluated. A near-complete and low-contamination draft genome was constructed from the metagenome of the DW biofilm, based on the coverage and tetranucleotide frequencies, and identified as a Bradyrhizobiaceae-like bacterium according to a phylogenetic analysis. Our findings provide new insight into DW biofilms, especially in terms of their metabolic functions.

  16. Situational Leadership And Diversity Management Coaching Skills

    OpenAIRE

    Bahaudin G. Mujtaba; Jatuporn Sungkhawan

    2011-01-01

    Leadership and diversity management have been part of the work life since the beginning of formal organizations and a critical element of globalization. The authors provide an overview of situational leadership and link it to diversity management so the focus can remain on productivity rather than personalities and biases which are part of each society and individual. Based on personal training experiences of the authors, this conceptual and practical paper provides a model to link situationa...

  17. Genetic diversity in some tunisian barley land races based on raped markers

    International Nuclear Information System (INIS)

    Abdellaos, R.; Kadir, K.; Naceur, M.B.; Kaab, L.B.B.

    2010-01-01

    The genetic diversity analysis of 15 barley land races was carried out using RAPD markers.These land races were collected from various bio climatic Tunisian zones. The amplification products varied from 4 to 11 bands ranging between 250 pb and 3000 pb. On 698 fragments counted, 578 are polymorphic showing a high level of polymorphism (82.8%). The relationship between the studied land races was evaluated according to (UPGMA) method that classified barley land races in 4 homogeneous groups. Among which, the group D included the majority of the land races with the introduced variety 'Martin'. The genetic distance between these land races is reduced, may be because of the presence of a common ancestor which led to a narrow genetic diversity. (author)

  18. Genetic diversity in some tunisian barley land races based on raped markers

    Energy Technology Data Exchange (ETDEWEB)

    Abdellaos, R; Kadir, K; Naceur, M B; Kaab, L B.B.,

    2010-12-15

    The genetic diversity analysis of 15 barley land races was carried out using RAPD markers.These land races were collected from various bio climatic Tunisian zones. The amplification products varied from 4 to 11 bands ranging between 250 pb and 3000 pb. On 698 fragments counted, 578 are polymorphic showing a high level of polymorphism (82.8%). The relationship between the studied land races was evaluated according to (UPGMA) method that classified barley land races in 4 homogeneous groups. Among which, the group D included the majority of the land races with the introduced variety 'Martin'. The genetic distance between these land races is reduced, may be because of the presence of a common ancestor which led to a narrow genetic diversity. (author)

  19. Intraspecies genomic diversity and natural population structure of the meat-borne lactic acid bacterium Lactobacillus sakei.

    Science.gov (United States)

    Chaillou, Stéphane; Daty, Marie; Baraige, Fabienne; Dudez, Anne-Marie; Anglade, Patricia; Jones, Rhys; Alpert, Carl-Alfred; Champomier-Vergès, Marie-Christine; Zagorec, Monique

    2009-02-01

    Lactobacillus sakei is a food-borne bacterium naturally found in meat and fish products. A study was performed to examine the intraspecies diversity among 73 isolates sourced from laboratory collections in several different countries. Pulsed-field gel electrophoresis analysis demonstrated a 25% variation in genome size between isolates, ranging from 1,815 kb to 2,310 kb. The relatedness between isolates was then determined using a PCR-based method that detects the possession of 60 chromosomal genes belonging to the flexible gene pool. Ten different strain clusters were identified that had noticeable differences in their average genome size reflecting the natural population structure. The results show that many different genotypes may be isolated from similar types of meat products, suggesting a complex ecological habitat in which intraspecies diversity may be required for successful adaptation. Finally, proteomic analysis revealed a slight difference between the migration patterns of highly abundant GapA isoforms of the two prevailing L. sakei subspecies (sakei and carnosus). This analysis was used to affiliate the genotypic clusters with the corresponding subspecies. These findings reveal for the first time the extent of intraspecies genomic diversity in L. sakei. Consequently, identification of molecular subtypes may in the future prove valuable for a better understanding of microbial ecosystems in food products.

  20. Drivers of aboveground wood production in a lowland tropical forest of West Africa: teasing apart the roles of tree density, tree diversity, soil phosphorus, and historical logging.

    Science.gov (United States)

    Jucker, Tommaso; Sanchez, Aida Cuni; Lindsell, Jeremy A; Allen, Harriet D; Amable, Gabriel S; Coomes, David A

    2016-06-01

    Tropical forests currently play a key role in regulating the terrestrial carbon cycle and abating climate change by storing carbon in wood. However, there remains considerable uncertainty as to whether tropical forests will continue to act as carbon sinks in the face of increased pressure from expanding human activities. Consequently, understanding what drives productivity in tropical forests is critical. We used permanent forest plot data from the Gola Rainforest National Park (Sierra Leone) - one of the largest tracts of intact tropical moist forest in West Africa - to explore how (1) stand basal area and tree diversity, (2) past disturbance associated with past logging, and (3) underlying soil nutrient gradients interact to determine rates of aboveground wood production (AWP). We started by statistically modeling the diameter growth of individual trees and used these models to estimate AWP for 142 permanent forest plots. We then used structural equation modeling to explore the direct and indirect pathways which shape rates of AWP. Across the plot network, stand basal area emerged as the strongest determinant of AWP, with densely packed stands exhibiting the fastest rates of AWP. In addition to stand packing density, both tree diversity and soil phosphorus content were also positively related to productivity. By contrast, historical logging activities negatively impacted AWP through the removal of large trees, which contributed disproportionately to productivity. Understanding what determines variation in wood production across tropical forest landscapes requires accounting for multiple interacting drivers - with stand structure, tree diversity, and soil nutrients all playing a key role. Importantly, our results also indicate that logging activities can have a long-lasting impact on a forest's ability to sequester and store carbon, emphasizing the importance of safeguarding old-growth tropical forests.

  1. Some Like it High! Phylogenetic Diversity of High-Elevation Cyanobacterial Community from Biological Soil Crusts of Western Himalaya.

    Science.gov (United States)

    Čapková, Kateřina; Hauer, Tomáš; Řeháková, Klára; Doležal, Jiří

    2016-01-01

    The environment of high-altitudinal cold deserts of Western Himalaya is characterized by extensive development of biological soil crusts, with cyanobacteria as dominant component. The knowledge of their taxonomic composition and dependency on soil chemistry and elevation is still fragmentary. We studied the abundance and the phylogenetic diversity of the culturable cyanobacteria and eukaryotic microalgae in soil crusts along altitudinal gradients (4600-5900 m) at two sites in the dry mountains of Ladakh (SW Tibetan Plateau and Eastern Karakoram), using both microscopic and molecular approaches. The effects of environmental factors (altitude, mountain range, and soil physico-chemical parameters) on the composition and biovolume of phototrophs were tested by multivariate redundancy analysis and variance partitioning. Both phylogenetic diversity and composition of morphotypes were similar between Karakorum and Tibetan Plateau. Phylogenetic analysis of 16S rRNA gene revealed strains belonging to at least five genera. Besides clusters of common soil genera, e.g., Microcoleus, Nodosilinea, or Nostoc, two distinct clades of simple trichal taxa were newly discovered. The most abundant cyanobacterial orders were Oscillatoriales and Nostacales, whose biovolume increased with increasing elevation, while that of Chroococales decreased. Cyanobacterial species richness was low in that only 15 morphotypes were detected. The environmental factors accounted for 52 % of the total variability in microbial data, 38.7 % of which was explained solely by soil chemical properties, 14.5 % by altitude, and 8.4 % by mountain range. The elevation, soil phosphate, and magnesium were the most important predictors of soil phototrophic communities in both mountain ranges despite their different bedrocks and origin. The present investigation represents a first record on phylogenetic diversity of the cyanobacterial community of biological soil crusts from Western Himalayas and first record

  2. Evaluating productivity-biodiversity relationship and spectral diversity in prairie grasslands under different fire management treatments using in-situ and remote sensing hyperspectral data

    Science.gov (United States)

    Gholizadeh, H.; Gamon, J. A.; Zygielbaum, A. I.; Schweiger, A. K.; Cavender-Bares, J.; Yang, Y.; Knops, J. M. H.

    2017-12-01

    Grasslands cover as much as 25% of the Earth's surface and account for approximately 20% of overall terrestrial productivity and contribute to global biodiversity. To optimize the status of grasslands and to counteract their degradation, different management practices have been adopted. Fire has been shown to be an important management practice in the maintenance of grasslands. Our main goals were 1) to evaluate the productivity-biodiversity relationship in grasslands under fire treatment, and 2) to evaluate the capability of hyperspectral remote sensing in estimating biodiversity using spectral data (i.e. spectral diversity). We used above-ground biomass (as a surrogate for productivity), species richness (SR; as a surrogate for biodiversity), and airborne hyperspectral data from a natural grassland with fire treatment (20 plots), and a natural grassland without fire treatment (21 plots), all located at the Cedar Creek Ecosystem Science Reserve in Central Minnesota, USA. The productivity-biodiversity relationship for the fire treatment plots showed a hump-shaped model with adjusted R2=0.37, whereas the relationship for the non-burned plots were non-significant. The relationship between SR and spectral diversity (SD) were positive linear for both treatments; however, the relationship for plots with fire treatment was higher (adjusted R2 = 0.34 vs. 0.19). It is assumed that post-fire foliar nutrients increase soil nitrogen and phosphorus which facilitate post-fire growth and induce higher above-ground biomass and chlorophyll content in plants. Overall, the results of this study showed that management practices affect the productivity-biodiversity relationship and illustrated the effect of fire treatment on remote sensing of biodiversity.

  3. Motivators of and Barriers to Health-Promoting Behaviors among Culturally Diverse Middle and High School Students

    Science.gov (United States)

    Wippold, Guillermo M.; Tucker, Carolyn M; Smith, Tasia M.; Rodriguez, Victoria A.; Hayes, Lynda F.; Folger, Austin C.

    2018-01-01

    Background: Youth obesity in the United States is a major health concern. Obesity can be reduced by increasing health-promoting behaviors. Purpose: The goals of the present study were to (1) identify the strongest motivators of and barriers to health-promoting behaviors among a culturally diverse group of middle and high school students and (2)…

  4. Arthropod Diversity and Functional Importance in Old-Growth Forests of North America

    Directory of Open Access Journals (Sweden)

    Timothy Schowalter

    2017-03-01

    Full Text Available Old-growth forests have become rare in North America but provide habitat for unique assemblages of species that often are rare in younger forests. Insects and related arthropods reach their highest diversity in old-growth forests because of their stable moderate temperature and relative humidity and the rich variety of resources represented by high plant species richness and structural complexity. Old-growth arthropod assemblages typically are distinct from those in younger, managed forests. Major subcommunities include the arboreal community that is composed of a rich assemblage of herbivores, fungivores, and their associated predators and parasitoids that function to regulate primary production and nutrient fluxes, the stem zone community that includes bark- and wood-boring species and their associated predators and parasitoids that initiate the decomposition of coarse woody debris, and the forest floor community composed of a variety of detritivores, fungivores, burrowers, and their associated predators and parasitoids that are instrumental in litter decomposition. Insect outbreaks are relatively rare in old-growth forests, where the diversity of resources and predators limit population growth. In turn, insects contribute to plant diversity and limit primary production of host plant species, thereby promoting development of old-growth forest characteristics. Arthropods also provide important functions in decomposition and nutrient cycling that may be lost in younger, managed forests with limited provision of coarse woody debris and accumulated litter. Protection of remnant old-growth forests within the forest matrix may be particularly valuable for maintaining the diversity of plant and arthropod predators that can minimize outbreaks, thereby contributing to resilience to changing environmental conditions.

  5. Origins of Cell-to-Cell Bioprocessing Diversity and Implications of the Extracellular Environment Revealed at the Single-Cell Level.

    Science.gov (United States)

    Vasdekis, A E; Silverman, A M; Stephanopoulos, G

    2015-12-14

    Bioprocess limitations imposed by microbial cell-to-cell phenotypic diversity remain poorly understood. To address this, we investigated the origins of such culture diversity during lipid production and assessed the impact of the fermentation microenvironment. We measured the single-cell lipid production dynamics in a time-invariant microfluidic environment and discovered that production is not monotonic, but rather sporadic with time. To characterize this, we introduce bioprocessing noise and identify its epigenetic origins. We linked such intracellular production fluctuations with cell-to-cell productivity diversity in culture. This unmasked the phenotypic diversity amplification by the culture microenvironment, a critical parameter in strain engineering as well as metabolic disease treatment.

  6. Various Ready-to-Eat Products from Retail Stores Linked to Occurrence of Diverse Listeria monocytogenes and Listeria spp. Isolates.

    Science.gov (United States)

    Vongkamjan, Kitiya; Fuangpaiboon, Janejira; Turner, Matthew P; Vuddhakul, Varaporn

    2016-02-01

    Listeriosis outbreaks have been associated with a variety of foods. This study investigated the prevalence and diversity of Listeria monocytogenes and Listeria spp. in ready-to-eat (RTE) products and evaluated the performance of a rapid detection method, the 3M molecular detection assay for L. monocytogenes (MDA-LM), for detection of L. monocytogenes. Assay results were compared with those obtained using the U.S. Food and Drug Administration standard culture method described in the Bacteriological Analytical Manual. Products (n = 200) were purchased from retail stores: 122 aquatic products, 22 products of animal origin, 18 vegetarian products, 15 deli meat products, 13 salad and vegetable products, 4 desserts, 2 egg-based products, and 4 other products. L. monocytogenes prevalence was comparable with both methods. Overall, 15 (7.5%) of 200 samples were positive for L. monocytogenes: 3% of aquatic products, 1.5% of products of animal origin, 1% of vegetarian products, and 2% of deli meat products. Compared with the standard culture method, the sensitivity, specificity, and the accuracy of the MDA-LM were 86.7% (95% confidence interval, 58.4 to 97.7%), 98.4% (95% confidence interval, 95.0 to 99.6%), and 97.5%, respectively. Using the culture-based method, 18 (9%) of 200 samples were positive for Listeria species other than L. monocytogenes. Listeria isolates from these samples were classified into nine allelic types (ATs). The majority of isolates were classified as ATs 58 and 74, which were identified as L. monocytogenes lineages I and IV, respectively. Listeria innocua and Listeria welshimeri also were represented by isolates of multiple ATs. The MDA-LM is a rapid and reliable technique for detecting L. monocytogenes in various RTE foods. Further study is needed to develop effective control strategies to reduce L. monocytogenes contamination in RTE foods.

  7. High genetic diversity and geographic subdivision of three lance nematode species (Hoplolaimus spp.) in the United States.

    Science.gov (United States)

    Holguin, Claudia M; Baeza, Juan A; Mueller, John D; Agudelo, Paula

    2015-07-01

    Lance nematodes (Hoplolaimus spp.) feed on the roots of a wide range of plants, some of which are agronomic crops. Morphometric values of amphimictic lance nematode species overlap considerably, and useful morphological characters for their discrimination require high magnification and significant diagnostic time. Given their morphological similarity, these Hoplolaimus species provide an interesting model to investigate hidden diversity in crop agroecosystems. In this scenario, H. galeatus may have been over-reported and the related species that are morphologically similar could be more widespread in the United States that has been recognized thus far. The main objectives of this study were to delimit Hoplolaimus galeatus and morphologically similar species using morphology, phylogeny, and a barcoding approach, and to estimate the genetic diversity and population structure of the species found. Molecular analyses were performed using sequences of the cytochrome c oxidase subunit 1 (Cox1) and the internal transcribed spacer (ITS1) on 23 populations. Four morphospecies were identified: H. galeatus, H. magnistylus, H. concaudajuvencus, and H. stephanus, along with a currently undescribed species. Pronounced genetic structure correlated with geographic origin was found for all species, except for H. galeatus. Hoplolaimus galeatus also exhibited low genetic diversity and the shortest genetic distances among populations. In contrast, H. stephanus, the species with the fewest reports from agricultural soils, was the most common and diverse species found. Results of this project may lead to better delimitation of lance nematode species in the United States by contributing to the understanding the diversity within this group.

  8. Does staff diversity imply openness to diversity?

    DEFF Research Database (Denmark)

    Lauring, Jakob; Selmer, Jan

    2013-01-01

    Purpose – Post-secondary educational organizations are currently some of the most diverse settings to be found. However, few educational studies have dealt with staff diversity and hardly any has looked outside the USA. The purpose of this paper is to present a study of members of international...... university departments in Denmark. The authors set out to investigate the relationship between different types of staff diversity and openness to diversity in terms of linguistic, visible, value, and informational heterogeneity. Design/methodology/approach – This study uses responses from 489 staff members......, was unrelated or negatively associated with positive diversity attitudes. Originality/value – Few studies deal with the role of staff diversity and no prior studies the authors know of have examined the link between diversity types and openness to diversity....

  9. Diversity Strategies to Mitigate Postulated Common Cause Failure Vulnerabilities

    International Nuclear Information System (INIS)

    Wood, Richard Thomas

    2010-01-01

    This paper describes an approach to establish effective mitigating strategies that can resolve potential common-cause failure (CCF) vulnerabilities in instrumentation and control (I and C) systems at nuclear power plants. A particular objective in the development of these strategies, which consist of combinations of diversity attributes and their associated criteria, is to address the unique characteristics of digital technology that can contribute to CCF concerns. The research approach employed to establish diversity strategies involves investigation of available documentation on diversity usage and experience from nuclear power and non-nuclear industries, capture of expert knowledge and lessons learned, determination of common practices, and assessment of the nature of CCFs and compensating diversity attributes. The resulting diversity strategies address considerations such as the effect of technology choices, the nature of CCF vulnerabilities, and the prospective impact of each diversity type. In particular, the impact of each attribute and criterion on the purpose, process, product, and performance aspects of diverse systems are considered.

  10. Cigar Product Modification Among High School Youth.

    Science.gov (United States)

    Trapl, Erika S; Koopman Gonzalez, Sarah J; Cofie, Leslie; Yoder, Laura D; Frank, Jean; Sterling, Kymberle L

    2018-02-07

    Prevalence of cigar use has been increasing among youth. Research indicates that youth are modifying cigar products either by "freaking" (ie, removing the filter paper) or "blunting" (removing the tobacco and supplementing or replacing with marijuana), yet little is known about youth who engage in this behavior. Thus, this study examines demographic and concurrent substance use behaviors of youth who modify cigars. Data from the 2013 Cuyahoga County Youth Risk Behavior survey were examined (n = 16 855). The survey collected data on demographics, cigar product use, cigar modification behaviors, and current cigarette, hookah and marijuana use. Responses to cigar product use items were used to create a composite to classify youth in one of eight unique user categories. Univariate and bivariate statistics were calculated using SPSS complex samples procedures. Overall, 15.2% reported current cigar product use, 11.0% reported current freaking, and 18.5% reported current blunt use; taken together, 25.3% of respondents reported any current use of a cigar product. When examined by user category, of those who endorsed any cigar product use, cigars, cigarillos, and little cigars use only was most endorsed (26.3%), followed by Blunt only (25.2%) and all three (ie, cigars, cigarillos, and little cigars, freaking, and blunting; 17.4%). A substantial proportion of high school youth who report using cigar products are modifying them in some way, with nearly half freaking and nearly two-thirds blunting. Given the FDA Center for Tobacco products recent extension of its regulatory authority to include cigar products, it is imperative to understand more about the prevalence of and reasons for cigar modification behaviors. Although the FDA has recently enacted regulatory authority over cigar products, little is known about cigar product modification. This is the first study to concurrently examine two unique cigar modification behaviors, "freaking" (ie, removing the filter paper) and

  11. Network Based High Speed Product Innovation

    DEFF Research Database (Denmark)

    Lindgren, Peter

    In the first decade of the 21st century, New Product Development has undergone major changes in the way NPD is managed and organised. This is due to changes in technology, market demands, and in the competencies of companies. As a result NPD organised in different forms of networks is predicted...... to be of ever-increasing importance to many different kinds of companies. This happens at the same times as the share of new products of total turnover and earnings is increasing at unprecedented speed in many firms and industries. The latter results in the need for very fast innovation and product development...... - a need that can almost only be resolved by organising NPD in some form of network configuration. The work of Peter Lindgren is on several aspects of network based high speed product innovation and contributes to a descriptive understanding of this phenomenon as well as with normative theory on how NPD...

  12. Carbohydrates in diversity-oriented synthesis: challenges and opportunities.

    Science.gov (United States)

    Lenci, E; Menchi, G; Trabocchi, A

    2016-01-21

    Over the last decade, Diversity-Oriented Synthesis (DOS) has become a new paradigm for developing large collections of structurally diverse small molecules as probes to investigate biological pathways, and to provide a larger array of the chemical space. Drug discovery and chemical biology are taking advantage of DOS approaches to exploit highly-diverse and complex molecular platforms, producing advances in both target and ligand discovery. In this view, carbohydrates are attractive building blocks for DOS libraries, due to their stereochemical diversity and high density of polar functional groups, thus offering many possibilities for chemical manipulation and scaffold decoration. This review will discuss research contributions and perspectives on the application of carbohydrate chemistry to explore the accessible chemical space through appendage, stereochemical and scaffold diversity.

  13. How Should Beta-Diversity Inform Biodiversity Conservation?

    Science.gov (United States)

    Socolar, Jacob B; Gilroy, James J; Kunin, William E; Edwards, David P

    2016-01-01

    To design robust protected area networks, accurately measure species losses, or understand the processes that maintain species diversity, conservation science must consider the organization of biodiversity in space. Central is beta-diversity--the component of regional diversity that accumulates from compositional differences between local species assemblages. We review how beta-diversity is impacted by human activities, including farming, selective logging, urbanization, species invasions, overhunting, and climate change. Beta-diversity increases, decreases, or remains unchanged by these impacts, depending on the balance of processes that cause species composition to become more different (biotic heterogenization) or more similar (biotic homogenization) between sites. While maintaining high beta-diversity is not always a desirable conservation outcome, understanding beta-diversity is essential for protecting regional diversity and can directly assist conservation planning. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Native wildflower plantings support wild bee abundance and diversity in agricultural landscapes across the United States.

    Science.gov (United States)

    Williams, Neal M; Ward, Kimiora L; Pope, Nathaniel; Isaacs, Rufus; Wilson, Julianna; May, Emily A; Ellis, Jamie; Daniels, Jaret; Pence, Akers; Ullmann, Katharina; Peters, Jeff

    2015-12-01

    Global trends in pollinator-dependent crops have raised awareness of the need to support managed and wild bee populations to ensure sustainable crop production. Provision of sufficient forage resources is a key element for promoting bee populations within human impacted landscapes, particularly those in agricultural lands where demand for pollination service is high and land use and management practices have reduced available flowering resources. Recent government incentives in North America and Europe support the planting of wildflowers to benefit pollinators; surprisingly, in North America there has been almost no rigorous testing of the performance of wildflower mixes, or their ability to support wild bee abundance and diversity. We tested different wildflower mixes in a spatially replicated, multiyear study in three regions of North America where production of pollinator-dependent crops is high: Florida, Michigan, and California. In each region, we quantified flowering among wildflower mixes composed of annual and perennial species, and with high and low relative diversity. We measured the abundance and species richness of wild bees, honey bees, and syrphid flies at each mix over two seasons. In each region, some but not all wildflower mixes provided significantly greater floral display area than unmanaged weedy control plots. Mixes also attracted greater abundance and richness of wild bees, although the identity of best mixes varied among regions. By partitioning floral display size from mix identity we show the importance of display size for attracting abundant and diverse wild bees. Season-long monitoring also revealed that designing mixes to provide continuous bloom throughout the growing season is critical to supporting the greatest pollinator species richness. Contrary to expectation, perennials bloomed in their first season, and complementarity in attraction of pollinators among annuals and perennials suggests that inclusion of functionally diverse

  15. Floristic diversity in fragmented Afromontane rainforests

    DEFF Research Database (Denmark)

    Schmitt, Christine B.; Denich, Manfred; Demissew, Sebsebe

    2010-01-01

    Ordination and indicator species analyses showed gradual variations in floristic diversity along the altitudinal gradient with a pronounced shift in species composition at ca. 1830 m. Upper montane forest is characterized by high fern diversity and indicator species that are Afromontane endemics...

  16. Genetic diversity and demographic instability in Riftia pachyptila tubeworms from eastern Pacific hydrothermal vents

    Science.gov (United States)

    Coykendall, D.K.; Johnson, S.B.; Karl, S.A.; Lutz, R.A.; Vrijenhoek, R.C.

    2011-01-01

    Background: Deep-sea hydrothermal vent animals occupy patchy and ephemeral habitats supported by chemosynthetic primary production. Volcanic and tectonic activities controlling the turnover of these habitats contribute to demographic instability that erodes genetic variation within and among colonies of these animals. We examined DNA sequences from one mitochondrial and three nuclear gene loci to assess genetic diversity in the siboglinid tubeworm, Riftia pachyptila, a widely distributed constituent of vents along the East Pacific Rise and Galpagos Rift. Results: Genetic differentiation (FST) among populations increased with geographical distances, as expected under a linear stepping-stone model of dispersal. Low levels of DNA sequence diversity occurred at all four loci, allowing us to exclude the hypothesis that an idiosyncratic selective sweep eliminated mitochondrial diversity alone. Total gene diversity declined with tectonic spreading rates. The southernmost populations, which are subjected to superfast spreading rates and high probabilities of extinction, are relatively homogenous genetically. Conclusions: Compared to other vent species, DNA sequence diversity is extremely low in R. pachyptila. Though its dispersal abilities appear to be effective, the low diversity, particularly in southern hemisphere populations, is consistent with frequent local extinction and (re)colonization events. ?? 2011 Coykendall et al; licensee BioMed Central Ltd.

  17. Iterative-Transform Phase Retrieval Using Adaptive Diversity

    Science.gov (United States)

    Dean, Bruce H.

    2007-01-01

    A phase-diverse iterative-transform phase-retrieval algorithm enables high spatial-frequency, high-dynamic-range, image-based wavefront sensing. [The terms phase-diverse, phase retrieval, image-based, and wavefront sensing are defined in the first of the two immediately preceding articles, Broadband Phase Retrieval for Image-Based Wavefront Sensing (GSC-14899-1).] As described below, no prior phase-retrieval algorithm has offered both high dynamic range and the capability to recover high spatial-frequency components. Each of the previously developed image-based phase-retrieval techniques can be classified into one of two categories: iterative transform or parametric. Among the modifications of the original iterative-transform approach has been the introduction of a defocus diversity function (also defined in the cited companion article). Modifications of the original parametric approach have included minimizing alternative objective functions as well as implementing a variety of nonlinear optimization methods. The iterative-transform approach offers the advantage of ability to recover low, middle, and high spatial frequencies, but has disadvantage of having a limited dynamic range to one wavelength or less. In contrast, parametric phase retrieval offers the advantage of high dynamic range, but is poorly suited for recovering higher spatial frequency aberrations. The present phase-diverse iterative transform phase-retrieval algorithm offers both the high-spatial-frequency capability of the iterative-transform approach and the high dynamic range of parametric phase-recovery techniques. In implementation, this is a focus-diverse iterative-transform phaseretrieval algorithm that incorporates an adaptive diversity function, which makes it possible to avoid phase unwrapping while preserving high-spatial-frequency recovery. The algorithm includes an inner and an outer loop (see figure). An initial estimate of phase is used to start the algorithm on the inner loop, wherein

  18. Diversity

    Science.gov (United States)

    Portraits In Courage Vol. VIII Portraits In Courage Vol. IX Portraits In Courage Vol. X AF Sites Social -Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce Executive Order 13548 : Virtual Diversity Conference Air Force Diversity & Inclusion Air Force Diversity Graphic There is no

  19. High production rate of IBAD-MgO buffered substrate

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizumi, M., E-mail: myoshizumi@istec.or.j [Superconductivity Research Laboratory, ISTEC, Shinonome 1-10-13, Koto-ku, Tokyo 135-0062 (Japan); Miyata, S.; Ibi, A.; Fukushima, H.; Yamada, Y.; Izumi, T.; Shiohara, Y. [Superconductivity Research Laboratory, ISTEC, Shinonome 1-10-13, Koto-ku, Tokyo 135-0062 (Japan)

    2009-10-15

    The conventional IBAD (Ion Beam Assisted Deposition) process using fluorite materials yields low production rates, resulting in high production cost, which reduces the motivation for practical application in spite of its high quality. The IBAD process using rock salt materials, e.g. MgO, is well known as a strong candidate of practical application due to its potential of high production rate and high in-plane grain alignment. In this work, the IBAD-MgO process was investigated for a newly developed architecture of PLD (Pulsed Laser Deposition)-CeO{sub 2}/sputter-LMO (LaMnO{sub 3})/IBAD-MgO/sputter-GZO (Gd{sub 2}Zr{sub 2}O{sub 7})/Hastelloy{sup TM} to make long buffered metal tapes with high properties and a high production rate. The 50 m-long IBAD-MgO substrates with about 4 deg. of DELTAphiCeO{sub 2} in an XRD phi scan could be fabricated repeatedly. A GdBCO (GdBa{sub 2}Cu{sub 3}O{sub x}) layer deposited on the buffered substrate showed the minimum I{sub c} value of 325 A/cm-w in a 41 m-long tape. Almost of the tape showed 500-600 A/cm-w of I{sub c} value. The deposition time for the IBAD-MgO layer was 60 s which was about 2 orders of magnitude shorter than the conventional IBAD process. The production rate of 24 m/h was realized at the IBAD-MgO process to fabricate the GdBCO coated conductor with high J{sub c} and I{sub c} properties.

  20. Production of highly charged ion beams with SECRAL

    International Nuclear Information System (INIS)

    Sun, L. T.; Zhao, H. W.; Zhang, X. Z.; Feng, Y. C.; Li, J. Y.; Guo, X. H.; Ma, H. Y.; Zhao, H. Y.; Ma, B. H.; Wang, H.; Li, X. X.; Jin, T.; Xie, D. Z.; Lu, W.; Cao, Y.; Shang, Y.

    2010-01-01

    Superconducting electron cyclotron resonance ion source with advanced design in Lanzhou (SECRAL) is an all-superconducting-magnet electron cyclotron resonance ion source (ECRIS) for the production of intense highly charged ion beams to meet the requirements of the Heavy Ion Research Facility in Lanzhou (HIRFL). To further enhance the performance of SECRAL, an aluminum chamber has been installed inside a 1.5 mm thick Ta liner used for the reduction of x-ray irradiation at the high voltage insulator. With double-frequency (18+14.5 GHz) heating and at maximum total microwave power of 2.0 kW, SECRAL has successfully produced quite a few very highly charged Xe ion beams, such as 10 e μA of Xe 37+ , 1 e μA of Xe 43+ , and 0.16 e μA of Ne-like Xe 44+ . To further explore the capability of the SECRAL in the production of highly charged heavy metal ion beams, a first test run on bismuth has been carried out recently. The main goal is to produce an intense Bi 31+ beam for HIRFL accelerator and to have a feel how well the SECRAL can do in the production of very highly charged Bi beams. During the test, though at microwave power less than 3 kW, more than 150 e μA of Bi 31+ , 22 e μA of Bi 41+ , and 1.5 e μA of Bi 50+ have been produced. All of these results have again demonstrated the great capability of the SECRAL source. This article will present the detailed results and brief discussions to the production of highly charged ion beams with SECRAL.

  1. First high-temperature electronics products survey 2005.

    Energy Technology Data Exchange (ETDEWEB)

    Normann, Randy Allen

    2006-04-01

    On April 4-5, 2005, a High-Temperature Electronics Products Workshop was held. This workshop engaged a number of governmental and private industry organizations sharing a common interest in the development of commercially available, high-temperature electronics. One of the outcomes of this meeting was an agreement to conduct an industry survey of high-temperature applications. This report covers the basic results of this survey.

  2. Preserving biological diversity in the face of large-scale demands for biofuels

    International Nuclear Information System (INIS)

    Cook, J.J.; Beyea, J.; Keeler, K.H.

    1991-01-01

    Large-scale production and harvesting of biomass to replace fossil fuels could reduce biological diversity by eliminating habitat for native species. Forests would be managed and harvested more intensively, and virtually all arable land unsuitable for high-value agriculture or silviculture might be used to grow crops dedicated to energy. Given the prospects for a potentially large increase in biofuel production, it is time now to develop strategies for mitigating the loss of biodiversity that might ensue. Planning at micro to macro scales will be crucial to minimize the ecological impacts of producing biofuels. In particular, cropping and harvesting systems will need to provide the biological, spatial, and temporal diversity characteristics of natural ecosystems and successional sequences, if we are to have this technology support the environmental health of the world rather than compromise it. Incorporation of these ecological values will be necessary to forestall costly environmental restoration, even at the cost of submaximal biomass productivity. It is therefore doubtful that all managers will take the longer view. Since the costs of biodiversity loss are largely external to economic markets, society cannot rely on the market to protect biodiversity, and some sort of intervention will be necessary. 116 refs., 1 tab

  3. Not all are free-living: high-throughput DNA metabarcoding reveals a diverse community of protists parasitizing soil metazoa

    NARCIS (Netherlands)

    Geisen, S.; Laros, I.; Vizcaino, A.; Bonkowski, M.; Groot, de G.A.

    2015-01-01

    Protists, the most diverse eukaryotes, are largely considered to be free-living bacterivores, but vast numbers of taxa are known to parasitize plants or animals. High-throughput sequencing (HTS) approaches now commonly replace cultivation-based approaches in studying soil protists, but insights into

  4. Extraordinary Genetic Diversity in a Wood Decay Mushroom.

    Science.gov (United States)

    Baranova, Maria A; Logacheva, Maria D; Penin, Aleksey A; Seplyarskiy, Vladimir B; Safonova, Yana Y; Naumenko, Sergey A; Klepikova, Anna V; Gerasimov, Evgeny S; Bazykin, Georgii A; James, Timothy Y; Kondrashov, Alexey S

    2015-10-01

    Populations of different species vary in the amounts of genetic diversity they possess. Nucleotide diversity π, the fraction of nucleotides that are different between two randomly chosen genotypes, has been known to range in eukaryotes between 0.0001 in Lynx lynx and 0.16 in Caenorhabditis brenneri. Here, we report the results of a comparative analysis of 24 haploid genotypes (12 from the United States and 12 from European Russia) of a split-gill fungus Schizophyllum commune. The diversity at synonymous sites is 0.20 in the American population of S. commune and 0.13 in the Russian population. This exceptionally high level of nucleotide diversity also leads to extreme amino acid diversity of protein-coding genes. Using whole-genome resequencing of 2 parental and 17 offspring haploid genotypes, we estimate that the mutation rate in S. commune is high, at 2.0 × 10(-8) (95% CI: 1.1 × 10(-8) to 4.1 × 10(-8)) per nucleotide per generation. Therefore, the high diversity of S. commune is primarily determined by its elevated mutation rate, although high effective population size likely also plays a role. Small genome size, ease of cultivation and completion of the life cycle in the laboratory, free-living haploid life stages and exceptionally high variability of S. commune make it a promising model organism for population, quantitative, and evolutionary genetics. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  5. Cercospora zeina from Maize in South Africa Exhibits High Genetic Diversity and Lack of Regional Population Differentiation.

    Science.gov (United States)

    Muller, Mischa F; Barnes, Irene; Kunene, Ncobile T; Crampton, Bridget G; Bluhm, Burton H; Phillips, Sonia M; Olivier, Nicholas A; Berger, Dave K

    2016-10-01

    South Africa is one of the leading maize-producing countries in sub-Saharan Africa. Since the 1980s, Cercospora zeina, a causal agent of gray leaf spot of maize, has become endemic in South Africa, and is responsible for substantial yield reductions. To assess genetic diversity and population structure of C. zeina in South Africa, 369 isolates were collected from commercial maize farms in three provinces (KwaZulu-Natal, Mpumalanga, and North West). These isolates were evaluated with 14 microsatellite markers and species-specific mating type markers that were designed from draft genome sequences of C. zeina isolates from Africa (CMW 25467) and the United States (USPA-4). Sixty alleles were identified across 14 loci, and gene diversity values within each province ranged from 0.18 to 0.35. High levels of gene flow were observed (Nm = 5.51), and in a few cases, identical multilocus haplotypes were found in different provinces. Overall, 242 unique multilocus haplotypes were identified with a low clonal fraction of 34%. No distinct population clusters were identified using STRUCTURE, principal coordinate analysis, or Weir's theta θ statistic. The lack of population differentiation was supported by analysis of molecular variance tests, which indicated that only 2% of the variation was attributed to variability between populations from each province. Mating type ratios of MAT1-1 and MAT1-2 idiomorphs from 335 isolates were not significantly different from a 1:1 ratio in all provinces, which provided evidence for sexual reproduction. The draft genome of C. zeina CMW 25467 exhibited a complete genomic copy of the MAT1-1 idiomorph as well as exonic fragments of MAT genes from both idiomorphs. The high level of gene diversity, shared haplotypes at different geographical locations within South Africa, and presence of both MAT idiomorphs at all sites indicates widespread dispersal of C. zeina between maize fields in the country as well as evidence for sexual recombination. The

  6. Genetic diversity and apple leaf spot disease resistance characterization assessed by SSR markers

    Directory of Open Access Journals (Sweden)

    Gustavo H.F. Klabunde

    2016-09-01

    Full Text Available Among the cultivation problems of apple production in Brazil, Apple Leaf Spot (ALS disease represents one of the main breeding challenges. This study aims at analyzing the genetic diversity among 152 apple scion accessions available at the Apple Gene Bank of EPAGRI, located in Caçador, Santa Catarina/ Brazil. Eleven genomic SSR loci were analyzed to assess genetic diversity of ALS resistant and susceptible accessions. Results revealed high genetic diversity of the studied accessions, being 120 exclusive alleles (67 unique from scion accessions resistant to ALS, and a mean PIC of 0.823. The locus Probability of Identity (I ranged from 0.017 to 0.089. The combined I was 4.11 x 10-16, and the Power of Exclusion was 99.99999259%. In addition, the DNA fingerprint patterns will contribute as additional descriptors to select parental for crosses and early identification of apple accessions for breeding purposes, and also for cultivar protection.

  7. Genetic diversity and population structure of Miscanthus sinensis germplasm in China.

    Directory of Open Access Journals (Sweden)

    Hua Zhao

    Full Text Available Miscanthus is a perennial rhizomatous C4 grass native to East Asia. Endowed with great biomass yield, high ligno-cellulose composition, efficient use of radiation, nutrient and water, as well as tolerance to stress, Miscanthus has great potential as an excellent bioenergy crop. Despite of the high potential for biomass production of the allotriploid hybrid M. ×giganteus, derived from M. sacchariflorus and M. sinensis, other options need to be explored to improve the narrow genetic base of M. ×giganteus, and also to exploit other Miscanthus species, including M. sinensis (2n = 2x = 38, as bioenergy crops. In the present study, a large number of 459 M. sinensis accessions, collected from the wide geographical distribution regions in China, were genotyped using 23 SSR markers transferable from Brachypodium distachyon. Genetic diversity and population structure were assessed. High genetic diversity and differentiation of the germplasm were observed, with 115 alleles in total, a polymorphic rate of 0.77, Nei's genetic diversity index (He of 0.32 and polymorphism information content (PIC of 0.26. Clustering of germplasm accessions was primarily in agreement with the natural geographic distribution. AMOVA and genetic distance analyses confirmed the genetic differentiation in the M. sinensis germplasm and it was grouped into five clusters or subpopulations. Significant genetic variation among subpopulations indicated obvious genetic differentiation in the collections, but within-subpopulation variation (83% was substantially greater than the between-subpopulation variation (17%. Considerable phenotypic variation was observed for multiple traits among 300 M. sinensis accessions. Nine SSR markers were found to be associated with heading date and biomass yield. The diverse Chinese M. sinensis germplasm and newly identified SSR markers were proved to be valuable for breeding Miscanthus varieties with desired bioenergy traits.

  8. Species Diversity and Functional Prediction of Surface Bacterial Communities on Aging Flue-Cured Tobaccos.

    Science.gov (United States)

    Wang, Fan; Zhao, Hongwei; Xiang, Haiying; Wu, Lijun; Men, Xiao; Qi, Chang; Chen, Guoqiang; Zhang, Haibo; Wang, Yi; Xian, Mo

    2018-06-05

    Microbes on aging flue-cured tobaccos (ATFs) improve the aroma and other qualities desirable in products. Understanding the relevant organisms would picture microbial community diversity, metabolic potential, and their applications. However, limited efforts have been made on characterizing the microbial quality and functional profiling. Herein, we present our investigation of the bacterial diversity and predicted potential genetic capability of the bacteria from two AFTs using 16S rRNA gene sequences and phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) software. The results show that dominant bacteria from AFT surfaces were classified into 48 genera, 36 families, and 7 phyla. In addition, Bacillus spp. was found prevalent on both ATFs. Furthermore, PICRUSt predictions of bacterial community functions revealed many attractive metabolic capacities in the AFT microbiota, including several involved in the biosynthesis of flavors and fragrances and the degradation of harmful compounds, such as nicotine and nitrite. These results provide insights into the importance of AFT bacteria in determining product qualities and indicate specific microbial species with predicted enzymatic capabilities for the production of high-efficiency flavors, the degradation of undesirable compounds, and the provision of nicotine and nitrite tolerance which suggest fruitful areas of investigation into the manipulation of AFT microbiota for AFT and other product improvements.

  9. Methods for high yield production of terpenes

    Energy Technology Data Exchange (ETDEWEB)

    Kutchan, Toni; Higashi, Yasuhiro; Feng, Xiaohong

    2017-01-03

    Provided are enhanced high yield production systems for producing terpenes in plants via the expression of fusion proteins comprising various combinations of geranyl diphosphate synthase large and small subunits and limonene synthases. Also provided are engineered oilseed plants that accumulate monoterpene and sesquiterpene hydrocarbons in their seeds, as well as methods for producing such plants, providing a system for rapidly engineering oilseed crop production platforms for terpene-based biofuels.

  10. International P/L Insurance Output, Input, and Productivity Comparisons

    OpenAIRE

    Mary A. Weiss

    1991-01-01

    This research provides (bilateral) divisia and multilateral divisia indexes of output, input, and productivity for the property-liability (P-L) insurance industry for the following countries: United States, West Germany, Switzerland, France, and Japan. The time period studied is 1975 to 1987. The results indicate that considerable diversity exists among different countries, with Japan showing the weakest productivity growth. The United States and West Germany are associated overall with high ...

  11. Investigating Effects of Participatory Range Management Plans on Species Diversity in Semirum-Isfahan Province

    Directory of Open Access Journals (Sweden)

    M. Borhani

    2016-05-01

    Full Text Available In order to investigate the effects of range management plans on species diversity, richness and evenness in Semirum rangelands, 52 sites (28 with treated plan and 24 without treated plan were selected. The non-parametric indices for species richness (Margalof, Menhinick, Jacknife and counting method and species diversity (Simpson, Camargo, Smith and Wilson and modified Nee were compared in two management plans. The mean comparisons were made by independent T Student Test and Mann-Witheny U Test, and correlation was determined between diversity indices and vegetation parameters. Based on the results there was no significant difference between the two management systems regarding environmental features, while the implementation of range management plans caused significant reduction of stocking rate. Among the studied indices, evenness of species in sites without treated plan was significantly more than the sites with treated plan. The correlation matrix showed that there was a significant positive correlation between species richness and vegetation cover, production of perennial plans, and the rangeland condition and trend, while evenness showed significant negative correlation with these indices. Generally, implementation of range management plans has considerable effect on increasing climax species, dominance of Bromus tomentellus and it causes improvement of rangeland condition and reduction of evenness. This behavior could be explained by the balance between species competition and grazing pressure. Further, succession process of the studied communities demonstrates domination of some desirable species, high production and less diversity.

  12. Prices and species diversity

    DEFF Research Database (Denmark)

    Sauer, Johannes

    of biodiversity and the appropriate incorporation in stochastic fron-tier models to achieve more realistic measures of production efficiency. We use the empirical example of tobacco production drawing from as well as affecting species diversity in the surrounding forests. We apply a shadow profit distance......In recent decades a significant amount of literature has been produced concerned with establishing a link between production efficiency and environmental efficiency with respect to quantitative modelling. This has been mainly addressed by focusing on the incorporation of undesirable outputs...... or the incorporation of environmentally det-rimental inputs. However, while the debate with respect to linear programming based DEA modelling is already at an advanced stage the corresponding one with respect to stochastic frontier modelling still needs considerable efforts. This contribution fo-cuses on the case...

  13. Improving industrial yeast strains: exploiting natural and artificial diversity.

    Science.gov (United States)

    Steensels, Jan; Snoek, Tim; Meersman, Esther; Picca Nicolino, Martina; Voordeckers, Karin; Verstrepen, Kevin J

    2014-09-01

    Yeasts have been used for thousands of years to make fermented foods and beverages, such as beer, wine, sake, and bread. However, the choice for a particular yeast strain or species for a specific industrial application is often based on historical, rather than scientific grounds. Moreover, new biotechnological yeast applications, such as the production of second-generation biofuels, confront yeast with environments and challenges that differ from those encountered in traditional food fermentations. Together, this implies that there are interesting opportunities to isolate or generate yeast variants that perform better than the currently used strains. Here, we discuss the different strategies of strain selection and improvement available for both conventional and nonconventional yeasts. Exploiting the existing natural diversity and using techniques such as mutagenesis, protoplast fusion, breeding, genome shuffling and directed evolution to generate artificial diversity, or the use of genetic modification strategies to alter traits in a more targeted way, have led to the selection of superior industrial yeasts. Furthermore, recent technological advances allowed the development of high-throughput techniques, such as 'global transcription machinery engineering' (gTME), to induce genetic variation, providing a new source of yeast genetic diversity. © 2014 The Authors. FEMS Microbiology Reviews published by John Wiley & Sons Ltd on behalf of Federation of European Microbiological Societies.

  14. Sustainable, efficient livestock production with high biodiversity and good welfare for animals.

    Science.gov (United States)

    Broom, D M; Galindo, F A; Murgueitio, E

    2013-11-22

    What is the future for livestock agriculture in the world? Consumers have concerns about sustainability but many widely used livestock production methods do not satisfy consumers' requirements for a sustainable system. However, production can be sustainable, occurring in environments that: supply the needs of the animals resulting in good welfare, allow coexistence with a wide diversity of organisms native to the area, minimize carbon footprint and provide a fair lifestyle for the people working there. Conservation need not just involve tiny islands of natural vegetation in a barren world of agriculture, as there can be great increases in biodiversity in farmed areas. Herbivores, especially ruminants that consume materials inedible by humans, are important for human food in the future. However, their diet should not be just ground-level plants. Silvopastoral systems, pastures with shrubs and trees as well as herbage, are described which are normally more productive than pasture alone. When compared with widely used livestock production systems, silvopastoral systems can provide efficient feed conversion, higher biodiversity, enhanced connectivity between habitat patches and better animal welfare, so they can replace existing systems in many parts of the world and should be further developed.

  15. The genetic diversity of commensal Escherichia coli strains isolated from nonantimicrobial treated pigs varies according to age group

    DEFF Research Database (Denmark)

    Ahmed, Shahana; Olsen, John E.; Herrero-Fresno, Ana

    2017-01-01

    This is the first report on the genetic diversity of commensal E. coli from pigs reared in an antibiotic free production system and belonging to different age groups. The study investigated the genetic diversity and relationship of 900 randomly collected commensal E. coli strains from non......-antimicrobial treated pigs assigned to five different age groups in a Danish farm. Fifty-two unique REP profiles were detected suggesting a high degree of diversity. The number of strains per pig ranged from two to 13. The highest and the lowest degree of diversity were found in the early weaners group (Shannon...... diversity index, H' of 2.22) and piglets (H' of 1.46) respectively. The REP profiles, R1, R7 and R28, were the most frequently observed in all age groups. E. coli strains representing each REP profile and additional strains associated with the dominant profiles were subjected to PFGE and were assigned to 67...

  16. Perspectives regarding disproportionate representation of culturally and linguistically diverse students in high-incidence special education programs in the United States

    Directory of Open Access Journals (Sweden)

    Jolanta Jonak

    2014-02-01

    Full Text Available Background The number of culturally and linguistically diverse students in the U.S. is growing, and research shows they are often underassessed, misdiagnosed, and placed into special education unnecessarily. This problem mainly concerns high-incidence, or judgmental, disabilities such as learning disability, emotional disturbance, or mental retardation. Participants and procedure In this study, the author examines how some educators perceive and address culturally and linguistically diverse students in the U.S. A survey developed by the author was used to examine how educators perceive culturally and linguistically diverse student populations and how one Midwestern school system in the United States dealt with culturally and linguistically diverse students’ needs versus expected ideal practices. Results Results indicated that most participants recognized that the issue of disproportionate representation is nationwide, but did not believe that their district shared that problem. Conclusions Participants indicated that best practices were not being followed maximally to reduce and avoid the problem of disproportionate representation of culturally and linguistically diverse students in special education programs. Difficulties in meeting students’ needs may be related to cultural differences that school personnel are unable to assess or address. Recommendations include suggestions for further studies and for applying the survey in other school systems to increase the understanding and improve their practice in working with culturally and linguistically diverse students.

  17. Quantitative measurement of vitamin K2 (menaquinones) in various fermented dairy products using a reliable high-performance liquid chromatography method.

    Science.gov (United States)

    Manoury, E; Jourdon, K; Boyaval, P; Fourcassié, P

    2013-03-01

    We evaluated menaquinone contents in a large set of 62 fermented dairy products samples by using a new liquid chromatography method for accurate quantification of lipo-soluble vitamin K(2), including distribution of individual menaquinones. The method used a simple and rapid purification step to remove matrix components in various fermented dairy products 3 times faster than a reference preparation step. Moreover, the chromatography elution time was significantly shortened and resolution and efficiency were optimized. We observed wide diversity of vitamin K(2) contents in the set of fermented dairy products, from undetectable to 1,100 ng/g of product, and a remarkable diversity of menaquinone forms among products. These observations relate to the main microorganism species currently in the different fermented product technologies. The major form in this large set of fermented dairy products was menaquinone (MK)-9, and contents of MK-9 and MK-8 forms were correlated, that of MK-9 being around 4 times that of MK-8, suggesting that microorganisms able to produce MK-9 also produce MK-8. This was not the case for the other menaquinones, which were produced independently of each other. Finally, no obvious link was established between MK-9 content and fat content or pH of the fermented dairy products. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  18. Population Structure, Genetic Diversity and Molecular Marker-Trait Association Analysis for High Temperature Stress Tolerance in Rice.

    Directory of Open Access Journals (Sweden)

    Sharat Kumar Pradhan

    Full Text Available Rice exhibits enormous genetic diversity, population structure and molecular marker-traits associated with abiotic stress tolerance to high temperature stress. A set of breeding lines and landraces representing 240 germplasm lines were studied. Based on spikelet fertility percent under high temperature, tolerant genotypes were broadly classified into four classes. Genetic diversity indicated a moderate level of genetic base of the population for the trait studied. Wright's F statistic estimates showed a deviation of Hardy-Weinberg expectation in the population. The analysis of molecular variance revealed 25 percent variation between population, 61 percent among individuals and 14 percent within individuals in the set. The STRUCTURE analysis categorized the entire population into three sub-populations and suggested that most of the landraces in each sub-population had a common primary ancestor with few admix individuals. The composition of materials in the panel showed the presence of many QTLs representing the entire genome for the expression of tolerance. The strongly associated marker RM547 tagged with spikelet fertility under stress and the markers like RM228, RM205, RM247, RM242, INDEL3 and RM314 indirectly controlling the high temperature stress tolerance were detected through both mixed linear model and general linear model TASSEL analysis. These markers can be deployed as a resource for marker-assisted breeding program of high temperature stress tolerance.

  19. Population Structure, Genetic Diversity and Molecular Marker-Trait Association Analysis for High Temperature Stress Tolerance in Rice.

    Science.gov (United States)

    Pradhan, Sharat Kumar; Barik, Saumya Ranjan; Sahoo, Ambika; Mohapatra, Sudipti; Nayak, Deepak Kumar; Mahender, Anumalla; Meher, Jitandriya; Anandan, Annamalai; Pandit, Elssa

    2016-01-01

    Rice exhibits enormous genetic diversity, population structure and molecular marker-traits associated with abiotic stress tolerance to high temperature stress. A set of breeding lines and landraces representing 240 germplasm lines were studied. Based on spikelet fertility percent under high temperature, tolerant genotypes were broadly classified into four classes. Genetic diversity indicated a moderate level of genetic base of the population for the trait studied. Wright's F statistic estimates showed a deviation of Hardy-Weinberg expectation in the population. The analysis of molecular variance revealed 25 percent variation between population, 61 percent among individuals and 14 percent within individuals in the set. The STRUCTURE analysis categorized the entire population into three sub-populations and suggested that most of the landraces in each sub-population had a common primary ancestor with few admix individuals. The composition of materials in the panel showed the presence of many QTLs representing the entire genome for the expression of tolerance. The strongly associated marker RM547 tagged with spikelet fertility under stress and the markers like RM228, RM205, RM247, RM242, INDEL3 and RM314 indirectly controlling the high temperature stress tolerance were detected through both mixed linear model and general linear model TASSEL analysis. These markers can be deployed as a resource for marker-assisted breeding program of high temperature stress tolerance.

  20. Study on genetic diversity in Pakistani wheat varieties using simple ...

    African Journals Online (AJOL)

    Common wheat ( Triticum aestivum L.) is a grass species, cultivated world wide. Globally, it is the most important human food grain and ranks second in total production as a cereal crop behind maize. Genetic diversity evaluation of germplasm is the basis of improvement in wheat. In the present study genetic diversity of 10 ...