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Sample records for factors limiting fish

  1. Concentration factors for fish

    International Nuclear Information System (INIS)

    Feldt, W.; Lauer, R.; Melzer, M.; Siebert, W.

    1978-01-01

    Concentration factors are defined as operators allowing to calculate the specific activity of fish meat from a given concentration of an element in the water. This parameter depends among others from the content of stable isotopes and homologues in the different waters. If this parameter is reasonably to be used for model calculations it must be referred to water with all of its content substances, these calculations also being based on this type of 'water'. (orig.) [de

  2. Endangered river fish: factors hindering conservation and restoration

    Science.gov (United States)

    Cooke, Steven J.; Paukert, Craig P.; Hogan, Zeb

    2012-01-01

    Globally, riverine fish face many anthropogenic threats including riparian and flood plain habitat degradation, altered hydrology, migration barriers, fisheries exploitation, environmental (climate) change, and introduction of invasive species. Collectively, these threats have made riverine fishes some of the most threatened taxa on the planet. Although much effort has been devoted to identifying the threats faced by river fish, there has been less effort devoted to identifying the factors that may hinder our ability to conserve and restore river fish populations and their watersheds. Therefore, we focus our efforts on identifying and discussing 10 general factors (can also be viewed as research and implementation needs) that constrain or hinder effective conservation action for endangered river fish: (1) limited basic natural history information; (2) limited appreciation for the scale/extent of migrations and the level of connectivity needed to sustain populations; (3) limited understanding of fish/river-flow relationships; (4) limited understanding of the seasonal aspects of river fish biology, particularly during winter and/or wet seasons; (5) challenges in predicting the response of river fish and river ecosystems to both environmental change and various restoration or management actions; (6) limited understanding of the ecosystem services provided by river fish; (7) the inherent difficulty in studying river fish; (8) limited understanding of the human dimension of river fish conservation and management; (9) limitations of single species approaches that often fail to address the broader-scale problems; and (10) limited effectiveness of governance structures that address endangered river fish populations and rivers that cross multiple jurisdictions. We suggest that these issues may need to be addressed to help protect, restore, or conserve river fish globally, particularly those that are endangered.

  3. Fish consumption limit for mercury compounds

    Directory of Open Access Journals (Sweden)

    Abbas Esmaili-Sari

    2011-09-01

    Full Text Available Background and objectives: Methyl mercury can carry out harmful effects on the reproductive, respiratory, and nervous system of human. Moreover, mercury is known as the most toxic heavy metal in nature. Fish and seafood consumption is the major MeHg exposure route for human. The present study tries to cover researches which have been conducted on mercury levels in 21 species of fish from Persian Gulf, Caspian Sea and Anzali Wetland during the past 6 years, and in addition to stating mercury level, it provides recommendations about the restriction of monthly fish consumption for each species separately. Material and methods: Fish samples were transferred to the laboratory and stored in refrigerator under -20oC until they were dissected. Afterwards, the muscle tissues were separated and dried. The dried samples were ground and changed into a homogenous powder and then the mercury concentration rate has been determined by advanced mercury analyzer, model 254. Results: In general, mercury contamination in fishes caught from Anzali Wetland was much more than fishes from Caspian Sea. Also, from among all studied fishes, oriental sole (Euryglossa orientalis, caught from Persian Gulf, allocated the most mercury level to itself with the rate of 5.61ml per kg., therefore, it exercises a severe consumption restriction for pregnant women and vulnerable groups. Conclusion: Based on the calculations, about 50% of fishes, mostly with short food chain, can be easily consumed during the year. However, with regard to Oriental sole (Euryglossa orientalis and shark (Carcharhinus dussumieri, caught from Persian Gulf, special consideration should be taken in their consumption. On the other hand, careful planning should be made for the high rate of fish consumption among fishing community.

  4. Apoptosis in fish: environmental factors and programmed cell death.

    Science.gov (United States)

    AnvariFar, Hossein; Amirkolaie, Abdolsamad Keramat; Miandare, Hamed Kolangi; Ouraji, Hossein; Jalali, M Ali; Üçüncü, Sema İşisağ

    2017-06-01

    Apoptosis, a form of programmed cell death, is a critical component in maintaining homeostasis and growth in all tissues and plays a significant role in immunity and cytotoxicity. In contrast to necrosis or traumatic cell death, apoptosis is a well-controlled and vital process characterized mainly by cytoplasmic shrinkage, chromatin condensation, DNA fragmentation, membrane blebbing and apoptotic bodies. Our understanding of apoptosis is partly based on observations in invertebrates but mainly in mammals. Despite the great advantages of fish models in studying vertebrate development and diseases and the tremendous interest observed in recent years, reports on apoptosis in fish are still limited. Although apoptotic machinery is well conserved between aquatic and terrestrial organisms throughout the history of evolution, some differences exist in key components of apoptotic pathways. Core parts of apoptotic machinery in fish are virtually expressed as equivalent to the mammalian models. Some differences are, however, evident, such as the extrinsic and intrinsic pathways of apoptosis including lack of a C-terminal region in the Fas-associated protein with a death domain in fish. Aquatic species inhabit a complex and highly fluctuating environment, making these species good examples to reveal features of apoptosis that may not be easily investigated in mammals. Therefore, in order to gain a wider view on programmed cell death in fish, interactions between the main environmental factors, chemicals and apoptosis are discussed in this review. It is indicated that apoptosis can be induced in fish by exposure to environmental stressors during different stages of the fish life cycle.

  5. The limiting layer of fish scales: Structure and properties.

    Science.gov (United States)

    Arola, D; Murcia, S; Stossel, M; Pahuja, R; Linley, T; Devaraj, Arun; Ramulu, M; Ossa, E A; Wang, J

    2018-02-01

    Fish scales serve as a flexible natural armor that have received increasing attention across the materials community. Most efforts in this area have focused on the composite structure of the predominately organic elasmodine, and limited work addresses the highly mineralized external portion known as the Limiting Layer (LL). This coating serves as the first barrier to external threats and plays an important role in resisting puncture. In this investigation the structure, composition and mechanical behavior of the LL were explored for three different fish, including the arapaima (Arapaima gigas), the tarpon (Megalops atlanticus) and the carp (Cyprinus carpio). The scales of these three fish have received the most attention within the materials community. Features of the LL were evaluated with respect to anatomical position to distinguish site-specific functional differences. Results show that there are significant differences in the surface morphology of the LL from posterior and anterior regions in the scales, and between the three fish species. The calcium to phosphorus ratio and the mineral to collagen ratios of the LL are not equivalent among the three fish. Results from nanoindentation showed that the LL of tarpon scales is the hardest, followed by the carp and the arapaima and the differences in hardness are related to the apatite structure, possibly induced by the growth rate and environment of each fish. The natural armor of fish, turtles and other animals, has become a topic of substantial scientific interest. The majority of investigations have focused on the more highly organic layer known as the elasmodine. The present study addresses the highly mineralized external portion known as the Limiting Layer (LL). Specifically, the structure, composition and mechanical behavior of the LL were explored for three different fish, including the arapaima (Arapaima gigas), the tarpon (Megalops atlanticus) and the carp (Cyprinus carpio). Results show that there are

  6. Environmental Factors Influencing Artisanal Fishing in Eastern ...

    African Journals Online (AJOL)

    user

    The study identified the environmental factors affecting artisanal fishing in. Eastern Obolo local government area of Akwa ... colonial administration (Anko &Eyo, 2003). According to Olomola (1998), artisanal ... The problems faced by artisanal fishers in Nigeria are not far from what is experienced by artisanal fishermen in ...

  7. Landscape genetics and limiting factors

    Science.gov (United States)

    Samuel A. Cushman; Andrew J. Shirk; Erin L. Landguth

    2013-01-01

    Population connectivity is mediated by the movement of organisms or propagules through landscapes. However, little is known about how variation in the pattern of landscape mosaics affects the detectability of landscape genetic relationships. The goal of this paper is to explore the impacts of limiting factors on landscape genetic processes using simulation...

  8. Impacts of fishing and environmental factors driving changes on littoral fish assemblages in a subtropical oceanic island

    Science.gov (United States)

    Sangil, Carlos; Martín-García, Laura; Hernández, José Carlos; Concepción, Laura; Fernández, Raúl; Clemente, Sabrina

    2013-08-01

    The structure of demersal fish assemblages of commercial interest was studied at 51 sites on La Palma Island (Canary Islands, northeastern Atlantic). On this island, demersal fish populations are limited and independent from other islands. As deep water separates the islands and the shallow sublittoral platforms are not continuous, adult inter-island migrations are not possible except between the islands of Lanzarote and Fuerteventura. Otherwise, each island functions as a closed system, and the status of an island fish assemblage depends on local environmental conditions and activities performed in situ by the islanders. These circumstances provide a unique opportunity to test the intrainsular variability of fish assemblages. With this background, environmental parameters, fishing pressure and distance to the MPA were considered to identify the main factors explaining the spatial variation of fish assemblages off La Palma Island. Twenty-six fish species were recorded, but 60% of the total fish biomass was represented by only five species (Sparisoma cretense, Pomadasys incisus, Canthidermis sufflamen, Diplodus cervinus cervinus and Bodianus scrofa). However, the structure of assemblages was heterogeneous in response to different variables and showed substantial spatial variation. The assemblages were strongly modified by the presence of upright seaweed cover, fishing activities, and certain environmental variables. Differences were more pronounced in species that occupied the higher trophic levels. The most disturbed assemblages were those located in areas with lower upright seaweed cover and with higher fishing pressure, whereas the best-preserved assemblages corresponded to sites with controlled fishing activities, located within the MPA.

  9. Relative and combined effects of habitat and fishing on reef fish communities across a limited fishing gradient at Ningaloo.

    Science.gov (United States)

    Wilson, Shaun K; Babcock, Russ C; Fisher, Rebecca; Holmes, Thomas H; Moore, James A Y; Thomson, Damian P

    2012-10-01

    Habitat degradation and fishing are major drivers of temporal and spatial changes in fish communities. The independent effects of these drivers are well documented, but the relative importance and interaction between fishing and habitat shifts is poorly understood, particularly in complex systems such as coral reefs. To assess the combined and relative effects of fishing and habitat we examined the composition of fish communities on patch reefs across a gradient of high to low structural complexity in fished and unfished areas of the Ningaloo Marine Park, Western Australia. Biomass and species richness of fish were positively correlated with structural complexity of reefs and negatively related to macroalgal cover. Total abundance of fish was also positively related to structural complexity, however this relationship was stronger on fished reefs than those where fishing is prohibited. The interaction between habitat condition and fishing pressure is primarily due to the high abundance of small bodied planktivorous fish on fished reefs. However, the influence of management zones on the abundance and biomass of predators and target species is small, implying spatial differences in fishing pressure are low and unlikely to be driving this interaction. Our results emphasise the importance of habitat in structuring reef fish communities on coral reefs especially when gradients in fishing pressure are low. The influence of fishing effort on this relationship may however become more important as fishing pressure increases. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Piscivory limits diversification of feeding morphology in centrarchid fishes.

    Science.gov (United States)

    Collar, David C; O'Meara, Brian C; Wainwright, Peter C; Near, Thomas J

    2009-06-01

    Proximity to an adaptive peak influences a lineage's potential to diversify. We tested whether piscivory, a high quality but functionally demanding trophic strategy, represents an adaptive peak that limits morphological diversification in the teleost fish clade, Centrarchidae. We synthesized published diet data and applied a well-resolved, multilocus and time-calibrated phylogeny to reconstruct ancestral piscivory. We measured functional features of the skull and performed principal components analysis on species' values for these variables. To assess the role of piscivory on morphological diversification, we compared the fit of several models of evolution for each principal component (PC), where model parameters were allowed to vary between lineages that differed in degree of piscivory. According to the best-fitting model, two adaptive peaks influenced PC 1 evolution, one peak shared between highly and moderately piscivorous lineages and another for nonpiscivores. Brownian motion better fit PCs 2, 3, and 4, but the best Brownian models infer a slow rate of PC 2 evolution shared among all piscivores and a uniquely slow rate of PC 4 evolution in highly piscivorous lineages. These results suggest that piscivory limits feeding morphology diversification, but this effect is most severe in lineages that exhibit an extreme form of this diet.

  11. Fish consumption preferences and factors influencing it

    Directory of Open Access Journals (Sweden)

    Mehmet Ferit Can

    2015-06-01

    Full Text Available Fish consumption preferences are affected by individuals’ socioeconomic characteristics. The aims of the present paper were (i to obtain information on fish consumption level and frequency; (ii to investigate the associations between the socioeconomic characteristics of consumers and their preferences; and (iii to examine the influence of determinants on fish consumption. Data were gathered through a questionnaire completed by a total of 127 randomly selected individuals from different socioeconomic backgrounds from the Antakya, Turkey. The average consumption was found to be 2.98 kg/person/year for fish. Anchovies, gilt-head sea bream, and sea bass were reported as the most consumed three species, respectively. Significant differences in fish consumption were found among age groups, gender groups, and education groups, as well as between marital statuses. A majority of the consumers eat fish once a month throughout the year or only during the winter months. Fish consumption level and frequency were significantly positively correlated with education (p<0.01, income (p<0.05 and total meat consumption (p<0.01. The stepwise multiple regression model explained 41.7% (p<0.01 of the total variance for fish consumption. The amount and frequency of the consumption in the region, which is very far below the world and Turkey average especially for lower socioeconomic groups and for less-consumed fish species, can be increased by certain policies, such as training, advertising and different marketing strategies. Moreover, consumption should be distributed equally throughout the year instead of consuming only in certain seasons.

  12. Preliminary disposal limits, plume interaction factors, and final disposal limits

    Energy Technology Data Exchange (ETDEWEB)

    Flach, G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2018-01-11

    In the 2008 E-Area Performance Assessment (PA), each final disposal limit was constructed as the product of a preliminary disposal limit and a plume interaction factor. The following mathematical development demonstrates that performance objectives are generally expected to be satisfied with high confidence under practical PA scenarios using this method. However, radionuclides that experience significant decay between a disposal unit and the 100-meter boundary, such as H-3 and Sr-90, can challenge performance objectives, depending on the disposed-of waste composition, facility geometry, and the significance of the plume interaction factor. Pros and cons of analyzing single disposal units or multiple disposal units as a group in the preliminary disposal limits analysis are also identified.

  13. 50 CFR 697.19 - Trap limits and trap tag requirements for vessels fishing with lobster traps.

    Science.gov (United States)

    2010-10-01

    ... vessels fishing with lobster traps. 697.19 Section 697.19 Wildlife and Fisheries FISHERY CONSERVATION AND... requirements for vessels fishing with lobster traps. (a) Trap limits for vessels fishing or authorized to fish... management area designation certificate or valid limited access American lobster permit specifying one or...

  14. Limiting factors in caribou population ecology

    Directory of Open Access Journals (Sweden)

    David R. Klein

    1991-10-01

    Full Text Available Caribou and wild reindeer populations fluctuate over time. On this fact there is general agreement. Factors responsible for population limitation and subsequent declines have been examined within the framework of animal population theory. There is, however, little agreement when factors limiting specific populations are generalized to Rangifer populations over broad geographic regions. Comparative examinations of wild Rangifer populations worldwide discloses that factors that have regulated those populations are highly variable between populations, apparently as a reflection of the differences in environmental variables unique to each population. Examples exist of populations where major regulating factors have been climatic extremes, predation, hunting mortality, food limitation, insects, parasites, disease, interspecific competition, and human developmental impacts or combinations of these factors. This diversity of limiting factors affecting caribou and wild reindeer populations is a reflection of the ecologial complexity of the species, a concept that has often been ignored in past efforts to reach management decisions by extrapolation from the limited localized knowledge available on the species.

  15. Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus).

    Science.gov (United States)

    Besson, M; Komen, H; Aubin, J; de Boer, I J M; Poelman, M; Quillet, E; Vancoillie, C; Vandeputte, M; van Arendonk, J A M

    2014-12-01

    In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal growth coefficient (TGC) and the feed conversion ratio (FCR). This approach was applied to a farm producing African catfish (Clarias gariepinus) in a recirculating aquaculture system (RAS). In the RAS, 2 factors could limit production level: the nitrogen treatment capacity of the biofilter or the fish density in rearing tanks at harvest. Profit calculation includes revenue from fish sales, cost of juveniles, cost of feed, cost of waste water treatment, and fixed costs. In the reference scenario, profit was modeled to zero. EV were calculated as the difference in profit per kilogram of fish between the current population mean for both traits (µt) and the next generation of selective breeding (µt+Δt) for either TGC or FCR. EV of TGC and FCR were calculated for three generations of hypothetical selection on either TGC or FCR (respectively 6.8% and 7.6% improvement per generation). The results show that changes in TGC and FCR can affect both the number of fish that can be stocked (number of batches per year and number of fish per batch) and the factor limiting production. The EV of TGC and FCR vary and depend on the limiting factors. When dissolved NH3-N is the limiting factor for both µt and µt+Δt, increasing TGC decreases the number of fish that can be stocked but increases the number of batches that can be grown. As a result, profit remains constant and EVTGC is zero. Increasing FCR, however, increases the number of fish stocked and the ratio of fish produced per kilogram of feed consumed ("economic efficiency"). The EVFCR is 0.14 €/kg of fish, and profit per kilogram of fish increases by about 10%. When density is the limiting factor for both µt and µt+Δt, the

  16. Factors limiting device efficiency in organic photovoltaics

    NARCIS (Netherlands)

    Janssen, R.A.J.; Nelson, J.

    2013-01-01

    The power conversion efficiency of the most efficient organic photovoltaic (OPV) cells has recently increased to over 10%. To enable further increases, the factors limiting the device efficiency in OPV must be identified. In this review, the operational mechanism of OPV cells is explained and the

  17. Factors affecting the recovery of fish populations in an industrial river. [Brown trout

    Energy Technology Data Exchange (ETDEWEB)

    Turnpenny, A W.M.; Williams, R

    1981-01-01

    The river Ebbw Fawr, an industrial river of South-East Wales, was investigated over a three-year period to follow the re-establishment of fish populations as a result of pollution control measures at coal washeries and a steelworks on the river. These measures were effective in reducing levels of toxic materials and restoring dissolved oxygen levels and pH values acceptable for fish. Five freshwater fish species became established in parts of the river during the study period (1974-77). The brown trout Salmo trutta l. was the first to enter, followed by eel Anguilla anguilla l., stoneloach Noemacheilus barbatulus l., stickleback Gasterosteus aculeatus l. and bullhead Cottus gobio l., respectively. The flounder Platicthys flesus l., a euryhaline species, penetrated the river beyond the upper tidal limit. The minnow Phoxinus phoxinus l., a resident of other parts of the Ebbw system, did not recolonise during the study. Calculated toxicities and the results of fish caging tests indicated that water quality was satisfactory for fish populations throughout the river with the possible exception of a short reach immediately below the steelworks. The absence of fish from some upstream reaches with good water quality was due to the limited numbers of fish available for recolonisation and their restricted movements. Good growth and condition factors among the recolonising brown trout stock suggest that a sport fishery could be developed on the river, though constraints on spawning due to residual silt pollution indicate that stocking with hatchery reared fish will be necessary to maintain trout numbers.

  18. Limiting Factors for External Reactor Vessel Cooling

    International Nuclear Information System (INIS)

    Cheung, F.B.

    2005-01-01

    The method of external reactor vessel cooling (ERVC) that involves flooding of the reactor cavity during a severe accident has been considered a viable means for in-vessel retention (IVR). For high-power reactors, however, there are some limiting factors that might adversely affect the feasibility of using ERVC as a means for IVR. In this paper, the key limiting factors for ERVC have been identified and critically discussed. These factors include the choking limit for steam venting (CLSV) through the bottleneck of the vessel/insulation structure, the critical heat flux (CHF) for downward-facing boiling on the vessel outer surface, and the two-phase flow instabilities in the natural circulation loop within the flooded cavity. To enhance ERVC, it is necessary to eliminate or relax these limiting factors. Accordingly, methods to enhance ERVC and thus improve margins for IVR have been proposed and demonstrated, using the APR1400 as an example. The strategy is based on using two distinctly different methods to enhance ERVC. One involves the use of an enhanced vessel/insulation design to facilitate steam venting through the bottleneck of the annular channel. The other involves the use of an appropriate vessel coating to promote downward-facing boiling. It is found that the use of an enhanced vessel/insulation design with bottleneck enlargement could greatly facilitate the process of steam venting through the bottleneck region as well as streamline the resulting two-phase motions in the annular channel. By selecting a suitable enhanced vessel/insulation design, not only the CLSV but also the CHF limits could be significantly increased. In addition, the problem associated with two-phase flow instabilities and flow-induced mechanical vibration could be minimized. It is also found that the use of vessel coatings made of microporous metallic layers could greatly facilitate downward-facing boiling on the vessel outer surface. With vessel coatings, the local CHF limits at

  19. Optimizing fish and stream-water mercury metrics for calculation of fish bioaccumulation factors

    Science.gov (United States)

    Paul Bradley; Karen Riva Murray; Barbara C. Scudder Elkenberry; Christopher D. Knightes; Celeste A. Journey; Mark A. Brigham

    2016-01-01

    Mercury (Hg) bioaccumulation factors (BAFs; ratios of Hg in fish [Hgfish] and water[Hgwater]) are used to develop Total Maximum Daily Load and water quality criteria for Hg-impaired waters. Protection of wildlife and human health depends directly on the accuracy of site-specific estimates of Hgfish and Hgwater and the predictability of the relation between these...

  20. Nucleon form factors. Probing the chiral limit

    Energy Technology Data Exchange (ETDEWEB)

    Goeckeler, M. [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Haegler, P. [Technische Univ. Muenchen, Garching (Germany). Physik-Dept.; Horsley, R. [Edinburgh Univ. (GB). School of Physics] (and others)

    2006-10-15

    The electromagnetic form factors provide important hints for the internal structure of the nucleon and continue to be of major interest for experimentalists. For an intermediate range of momentum transfers the form factors can be calculated on the lattice. However, reliability of the results is limited by systematic errors due to the required extrapolation to physical quark masses. Chiral effective field theories predict a rather strong quark mass dependence in a range which was yet unaccessible for lattice simulations. We give an update on recent results from the QCDSF collaboration using gauge configurations with Nf=2, non-perturbatively O(a)-improved Wilson fermions at very small quark masses down to 340 MeV pion mass, where we start to probe the relevant quark mass region. (orig.)

  1. Nucleon form factors. Probing the chiral limit

    International Nuclear Information System (INIS)

    Goeckeler, M.; Haegler, P.; Horsley, R.

    2006-10-01

    The electromagnetic form factors provide important hints for the internal structure of the nucleon and continue to be of major interest for experimentalists. For an intermediate range of momentum transfers the form factors can be calculated on the lattice. However, reliability of the results is limited by systematic errors due to the required extrapolation to physical quark masses. Chiral effective field theories predict a rather strong quark mass dependence in a range which was yet unaccessible for lattice simulations. We give an update on recent results from the QCDSF collaboration using gauge configurations with Nf=2, non-perturbatively O(a)-improved Wilson fermions at very small quark masses down to 340 MeV pion mass, where we start to probe the relevant quark mass region. (orig.)

  2. Carbon Monoxide in Meat and Fish Packaging: Advantages and Limits

    Science.gov (United States)

    Roncalés, Pedro

    2018-01-01

    Due to increased demands for greater expectation in relation to quality, convenience, safety and extended shelf-life, combined with growing demand from retailers for cost-effective extensions of fresh muscle foods’ shelf-life, the food packaging industry quickly developed to meet these expectations. During the last few decades, modified atmosphere packaging (MAP) of foods has been a promising area of research, but much remains to be known regarding the use of unconventional gases such carbon monoxide (CO). The use of CO for meat and seafood packaging is not allowed in most countries due to the potential toxic effect, and its use is controversial in some countries. The commercial application of CO in food packaging was not then considered feasible because of possible environmental hazards for workers. CO has previously been reported to mask muscle foods’ spoilage, and this was the primary concern raised for the prohibition, as this may mislead consumers. This review was undertaken to present the most comprehensive and current overview of the widely-available, scattered information about the use of CO in the preservation of muscle foods. The advantages of CO and its industrial limits are presented and discussed. The most recent literature on the consumer safety issues related to the use of CO and consumer acceptance of CO especially in meat packaging systems were also discussed. Recommendations and future prospects were addressed for food industries, consumers and regulators on what would be a “best practice” in the use of CO in food packaging. All this promotes high ethical standards in commercial communications by means of effective regulation, for the benefit of consumers and businesses in the world, and this implies that industrialized countries and members of their regulatory agencies must develop a coherent and robust systems of regulation and control that can respond effectively to new challenges. PMID:29360803

  3. Carbon Monoxide in Meat and Fish Packaging: Advantages and Limits

    Directory of Open Access Journals (Sweden)

    Djamel Djenane

    2018-01-01

    Full Text Available Due to increased demands for greater expectation in relation to quality, convenience, safety and extended shelf-life, combined with growing demand from retailers for cost-effective extensions of fresh muscle foods’ shelf-life, the food packaging industry quickly developed to meet these expectations. During the last few decades, modified atmosphere packaging (MAP of foods has been a promising area of research, but much remains to be known regarding the use of unconventional gases such carbon monoxide (CO. The use of CO for meat and seafood packaging is not allowed in most countries due to the potential toxic effect, and its use is controversial in some countries. The commercial application of CO in food packaging was not then considered feasible because of possible environmental hazards for workers. CO has previously been reported to mask muscle foods’ spoilage, and this was the primary concern raised for the prohibition, as this may mislead consumers. This review was undertaken to present the most comprehensive and current overview of the widely-available, scattered information about the use of CO in the preservation of muscle foods. The advantages of CO and its industrial limits are presented and discussed. The most recent literature on the consumer safety issues related to the use of CO and consumer acceptance of CO especially in meat packaging systems were also discussed. Recommendations and future prospects were addressed for food industries, consumers and regulators on what would be a “best practice” in the use of CO in food packaging. All this promotes high ethical standards in commercial communications by means of effective regulation, for the benefit of consumers and businesses in the world, and this implies that industrialized countries and members of their regulatory agencies must develop a coherent and robust systems of regulation and control that can respond effectively to new challenges.

  4. Limitation and facilitation of one of the world's most invasive fish: an intercontinental comparison

    Science.gov (United States)

    Budy, Phaedra E.; Thiede, Gary P.; Lobón-Cerviá, Javier; Fernandez, Gustavo Gonzolez; McHugh, Peter; McIntosh, Angus; Vøllestad, Lief Asbjørn; Becares, Eloy; Jellyman, Phillip

    2013-01-01

    Purposeful species introductions offer opportunities to inform our understanding of both invasion success and conservation hurdles. We evaluated factors determining the energetic limitations of brown trout (Salmo trutta) in both their native and introduced ranges. Our focus was on brown trout because they are nearly globally distributed, considered one of the world's worst invaders, yet imperiled in much of their native habitat. We synthesized and compared data describing temperature regime, diet, growth, and maximum body size across multiple spatial and temporal scales, from country (both exotic and native habitats) and major geographic area (MGA) to rivers and years within MGA. Using these data as inputs, we next used bioenergetic efficiency (BioEff), a relative scalar representing a realized percentage of maximum possible consumption (0–100%) as our primary response variable and a multi-scale, nested, mixed statistical model (GLIMMIX) to evaluate variation among and within spatial scales and as a function of density and elevation. MGA and year (the residual) explained the greatest proportion of variance in BioEff. Temperature varied widely among MGA and was a strong driver of variation in BioEff. We observed surprisingly little variation in the diet of brown trout, except the overwhelming influence of the switch to piscivory observed only in exotic MGA. We observed only a weak signal of density-dependent effects on BioEff; however, BioEff remained 2.5 fish/m2. The trajectory of BioEff across the life span of the fish elucidated the substantial variation in performance among MGAs; the maximum body size attained by brown trout was consistently below 400 mm in native habitat but reached 600 mm outside their native range, where brown trout grew rapidly, feeding in part on naive prey fishes. The integrative, physiological approach, in combination with the intercontinental and comparative nature of our study, allowed us to overcome challenges associated with context

  5. 14 CFR 27.337 - Limit maneuvering load factor.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 27.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

  6. 14 CFR 29.337 - Limit maneuvering load factor.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit maneuvering load factor. 29.337... Limit maneuvering load factor. The rotorcraft must be designed for— (a) A limit maneuvering load factor... load factor not less than 2.0 and any negative limit maneuvering load factor of not less than −0.5 for...

  7. Factors Which Influence The Fish Purchasing Decision: A study on Traditional Market in Riau Mainland

    Science.gov (United States)

    Siswati, Latifa; Putri, Asgami

    2018-05-01

    The purposes of the research are to analyze and assess the factors which influence fish purchasing by the community at Tenayan Raya district Pekanbaru.Research methodology which used is survey method, especially interview and observation technique or direct supervision on the market which located at Tenayan Raya district. Determination technique of sampling location/region is done by purposive sampling. The sampling method is done by accidental sampling. Technique analysis of factors which used using the data that derived from the respondent opinion to various fish variable. The result of this research are the factors which influence fish purchasing decision done in a traditional market which located at Tenayan Raya district are product factor, price factors, social factor and individual factor. Product factor which influences fish purchasing decision as follows: the eyelets condition, the nutrition of fresh fish, the diversity of sold fish. Price factors influence the fish purchasing decision, such as: the price of fresh fish, the convincing price and the suitability price and benefits of the fresh fish. Individual factors which influence a fish purchasing decision, such as education and income levels. Social factors which influence a fish purchasing decision, such as family, colleagues and feeding habits of fish.

  8. Uranium, a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    Ohnemus, J.

    2006-01-01

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this step was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken into account: stocks, resources, and reserves. To clarify the situation, this article outlines important aspects of short and long term uranium supplies, and analyzes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the influence of the price of uranium on the cost of electricity generation? Among other results, it is found that comprehensive sources of low-price uranium and nuclear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig.)

  9. Uranium, a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    2006-01-01

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this step was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken into account: stocks, resources, and reserves. To clarify the situation, this article outlines important aspects of short and long term uranium supplies, and analyzes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the influence of the price of uranium on the cost of electricity generation? Among other results, it is found that comprehensive sources of low-price uranium and nuclear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig./GL)

  10. Uranium - a factor limiting nuclear energy?

    International Nuclear Information System (INIS)

    Ohnemus, J.

    2006-01-01

    Nuclear power has been back as a topic of public debate since early this year. A special subject under discussion is the extension of nuclear power plant life. Hardly had it been on the agenda, when interested parties announced that this st ep was impossible because uranium reserves were no longer sufficient. A variety of terms are being used in this discussion without their meaning being taken int o account: stocks, resources, and reserves. To clarify the situation, this artic le outlines important aspects of short and long term uranium supplies, and analy zes their meaning. Here are some of the most important issues under consideration: - For what period of time is there really enough uranium? - Is uranium becoming the limiting factor in the use of nuclear power? - Is uranium really a 'sustainable' energy resource? - Will higher prices extend the range? - What is the in fluence of the price of uranium on the cost of electricity generation? Among oth er results, it is found that comprehensive sources of low-price uranium and nucl ear fuels are, or can be made, available worldwide. Consequently, the 'range' is beyond the time frames currently mentioned, also as a function of technological factors, i.e. reaching several hundred years. It is also important to note that nuclear power - ensures greater independence of volatile imported sources, - guarantees reliably low electricity prices, - has a huge potential of environmental protection, and - is a clean source of energy. (orig.)

  11. Physiology-based modelling approaches to characterize fish habitat suitability: Their usefulness and limitations

    Science.gov (United States)

    Teal, Lorna R.; Marras, Stefano; Peck, Myron A.; Domenici, Paolo

    2018-02-01

    Models are useful tools for predicting the impact of global change on species distribution and abundance. As ectotherms, fish are being challenged to adapt or track changes in their environment, either in time through a phenological shift or in space by a biogeographic shift. Past modelling efforts have largely been based on correlative Species Distribution Models, which use known occurrences of species across landscapes of interest to define sets of conditions under which species are likely to maintain populations. The practical advantages of this correlative approach are its simplicity and the flexibility in terms of data requirements. However, effective conservation management requires models that make projections beyond the range of available data. One way to deal with such an extrapolation is to use a mechanistic approach based on physiological processes underlying climate change effects on organisms. Here we illustrate two approaches for developing physiology-based models to characterize fish habitat suitability. (i) Aerobic Scope Models (ASM) are based on the relationship between environmental factors and aerobic scope (defined as the difference between maximum and standard (basal) metabolism). This approach is based on experimental data collected by using a number of treatments that allow a function to be derived to predict aerobic metabolic scope from the stressor/environmental factor(s). This function is then integrated with environmental (oceanographic) data of current and future scenarios. For any given species, this approach allows habitat suitability maps to be generated at various spatiotemporal scales. The strength of the ASM approach relies on the estimate of relative performance when comparing, for example, different locations or different species. (ii) Dynamic Energy Budget (DEB) models are based on first principles including the idea that metabolism is organised in the same way within all animals. The (standard) DEB model aims to describe

  12. Factors influencing the marketing of fresh fish in Ogun State, Nigeria ...

    African Journals Online (AJOL)

    Factors influencing the marketing of fresh fish in Ogun State, Nigeria. ... The market prices of Clarias spp. ranged between □250 □400/Kg and the farmers were mostly patronized by retailers. Fish farm ... EMAIL FULL TEXT EMAIL FULL TEXT

  13. The effectiveness of fish oil supplementation in asthmatic rats is limited by an inefficient action on ASM function.

    Science.gov (United States)

    Miranda, D T S Z; Zanatta, A L; Dias, B C L; Fogaça, R T H; Maurer, J B B; Donatti, L; Calder, P C; Nishiyama, A

    2013-09-01

    Episodes of acute exacerbation are the major clinical feature of asthma and therefore represent an important focus for developing novel therapies for this disease. There are many reports that the n-3 fatty acids found in fish oil exert anti-inflammatory effects, but there are few studies of the action of fish oil on airway smooth muscle (ASM) function. In the present investigation, we evaluated the effect of fish oil supplementation on smooth muscle force of contraction in ovalbumin-induced asthmatic Wistar rats, and its consequences on static lung compliance, mucus production, leukocyte chemotaxis and production of proinflammatory cytokines. Fish oil supplementation suppressed the infiltration of inflammatory cells into the lung in asthmatic animals (2.04 ± 0.19 × 10(6) cells vs. 3.33 ± 0.43 × 10(6) cells in the control asthmatic group; P < 0.05). Static lung compliance increased with fish oil supplementation in asthmatic rats (0.640 ± 0.053 mL/cm H2O vs. 0.399 ± 0.043 mL/cm H2O; P < 0.05). However, fish oil did not prevent asthma-associated lung eosinophilia and did not affect the concentrations of tumor necrosis factor-α and interleukin-1β in lung tissue or the proportion of the airways obliterated with mucus. Fish oil had no effect on the force of contraction in asthmatic rats in response to acetylcholine (3.026 ± 0.274 mN vs. 2.813 ± 0.364 mN in the control asthmatic group). In conclusion, although fish oil exerts some benefits in this model of asthma, its effectiveness appears to be limited by an inefficient action on airway smooth muscle function.

  14. Perceived factors limiting rice production in Pategi Local ...

    African Journals Online (AJOL)

    user

    perceived limiting factors in rice production include lack of rice processing ... This production increase has not been enough to meet the consumption demand of ... of Kwara State, Nigeria seeks to determine some of the factors limiting rice ...

  15. Oxygen limitation and tissue metabolic potential of the African fish Barbus neumayeri: roles of native habitat and acclimatization

    Directory of Open Access Journals (Sweden)

    Rees Bernard B

    2011-01-01

    Full Text Available Abstract Background Oxygen availability in aquatic habitats is a major environmental factor influencing the ecology, behaviour, and physiology of fishes. This study evaluates the contribution of source population and hypoxic acclimatization of the African fish, Barbus neumayeri, in determining growth and tissue metabolic enzyme activities. Individuals were collected from two sites differing dramatically in concentration of dissolved oxygen (DO, Rwembaita Swamp (annual average DO 1.35 mgO2 L-1 and Inlet Stream West (annual average DO 5.58 mgO2 L-1 in Kibale National Park, Uganda, and reciprocally transplanted using a cage experiment in the field, allowing us to maintain individuals under natural conditions of oxygen, food availability, and flow. Fish were maintained under these conditions for four weeks and sampled for growth rate and the activities of phosphofructokinase (PFK, lactate dehydrogenase (LDH, citrate synthase (CS, and cytochrome c oxidase (CCO in four tissues, liver, heart, brain, and skeletal muscle. Results Acclimatization to the low DO site resulted in lower growth rates, lower activities of the aerobic enzyme CCO in heart, and higher activities of the glycolytic enzyme PFK in heart and skeletal muscle. The activity of LDH in liver tissue was correlated with site of origin, being higher in fish collected from a hypoxic habitat, regardless of acclimatization treatment. Conclusions Our results suggest that the influence of site of origin and hypoxic acclimatization in determining enzyme activity differs among enzymes and tissues, but both factors contribute to higher glycolytic capacity and lower aerobic capacity in B. neumayeri under naturally-occurring conditions of oxygen limitation.

  16. Hankin and Reeves' approach to estimating fish abundance in small streams: limitations and potential options; TOPICAL

    International Nuclear Information System (INIS)

    Thompson, William L.

    2000-01-01

    Hankin and Reeves' (1988) approach to estimating fish abundance in small streams has been applied in stream-fish studies across North America. However, as with any method of population estimation, there are important assumptions that must be met for estimates to be minimally biased and reasonably precise. Consequently, I investigated effects of various levels of departure from these assumptions via simulation based on results from an example application in Hankin and Reeves (1988) and a spatially clustered population. Coverage of 95% confidence intervals averaged about 5% less than nominal when removal estimates equaled true numbers within sampling units, but averaged 62% - 86% less than nominal when they did not, with the exception where detection probabilities of individuals were and gt;0.85 and constant across sampling units (95% confidence interval coverage= 90%). True total abundances averaged far (20% - 41%) below the lower confidence limit when not included within intervals, which implies large negative bias. Further, average coefficient of variation was about 1.5 times higher when removal estimates did not equal true numbers within sampling units (C(bar V)0.27[SE= 0.0004]) than when they did (C(bar V)= 0.19[SE= 0.0002]). A potential modification to Hankin and Reeves' approach is to include environmental covariates that affect detection rates of fish into the removal model or other mark-recapture model. A potential alternative is to use snorkeling in combination with line transect sampling to estimate fish densities. Regardless of the method of population estimation, a pilot study should be conducted to validate the enumeration method, which requires a known (or nearly so) population of fish to serve as a benchmark to evaluate bias and precision of population estimates

  17. Ecological limit functions relating fish community response to hydrologic departures of the ecological flow regime in the Tennessee River basin, United States

    Science.gov (United States)

    Knight, Rodney R.; Murphy, Jennifer C.; Wolfe, William J.; Saylor, Charles F.; Wales, Amy K.

    2014-01-01

    Ecological limit functions relating streamflow and aquatic ecosystems remain elusive despite decades of research. We investigated functional relationships between species richness and changes in streamflow characteristics at 662 fish sampling sites in the Tennessee River basin. Our approach included the following: (1) a brief summary of relevant literature on functional relations between fish and streamflow, (2) the development of ecological limit functions that describe the strongest discernible relationships between fish species richness and streamflow characteristics, (3) the evaluation of proposed definitions of hydrologic reference conditions, and (4) an investigation of the internal structures of wedge-shaped distributions underlying ecological limit functions.Twenty-one ecological limit functions were developed across three ecoregions that relate the species richness of 11 fish groups and departures from hydrologic reference conditions using multivariate and quantile regression methods. Each negatively sloped function is described using up to four streamflow characteristics expressed in terms of cumulative departure from hydrologic reference conditions. Negative slopes indicate increased departure results in decreased species richness.Sites with the highest measured fish species richness generally had near-reference hydrologic conditions for a given ecoregion. Hydrology did not generally differ between sites with the highest and lowest fish species richness, indicating that other environmental factors likely limit species richness at sites with reference hydrology.Use of ecological limit functions to make decisions regarding proposed hydrologic regime changes, although commonly presented as a management tool, is not as straightforward or informative as often assumed. We contend that statistical evaluation of the internal wedge structure below limit functions may provide a probabilistic understanding of how aquatic ecology is influenced by altered hydrology

  18. Genetic transformation of barley: limiting factors

    Czech Academy of Sciences Publication Activity Database

    Vyroubalová, Š.; Šmehilová, M.; Galuszka, P.; Ohnoutková, Ludmila

    2011-01-01

    Roč. 55, č. 2 (2011), s. 213-224 ISSN 0006-3134 R&D Projects: GA ČR GD522/08/H003; GA MŠk 1M06030 Institutional research plan: CEZ:AV0Z50380511 Keywords : Agrobacterium * albinism * Hordeum Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.974, year: 2011

  19. Radiation risk factors and dose limits

    International Nuclear Information System (INIS)

    Barendsen, G.W.

    1979-01-01

    The contents of the ICRP publications 9 (1965) and 26 (1977) are outlined and the research conducted during these years considered. Expressions are derived for the frequency for induction of cancer from the most common irradiations - X rays, gamma rays and electrons. The dose limits advised by the ICRP are discussed and the first two fundamental principles are presented - that no one should be subjected to radiation without useful cause and that in those cases where irradiation is thought necessary, the medical, scientific, social and economic advantages need to be carefully considered with respect to the possible disadvantages. (C.F.)

  20. Preliminary assessment of factors influencing riverine fish communities in Massachusetts.

    Science.gov (United States)

    Armstrong, David S.; Richards, Todd A.; Brandt, Sara L.

    2010-01-01

    The U.S. Geological Survey, in cooperation with the Massachusetts Department of Conservation and Recreation (MDCR), Massachusetts Department of Environmental Protection (MDEP), and the Massachusetts Department of Fish and Game (MDFG), conducted a preliminary investigation of fish communities in small- to medium-sized Massachusetts streams. The objective of this investigation was to determine relations between fish-community characteristics and anthropogenic alteration, including flow alteration and impervious cover, relative to the effect of physical basin and land-cover (environmental) characteristics. Fish data were obtained for 756 fish-sampling sites from the Massachusetts Division of Fisheries and Wildlife fish-community database. A review of the literature was used to select a set of fish metrics responsive to flow alteration. Fish metrics tested include two fish-community metrics (fluvial-fish relative abundance and fluvial-fish species richness), and five indicator species metrics (relative abundance of brook trout, blacknose dace, fallfish, white sucker, and redfin pickerel). Streamflows were simulated for each fish-sampling site using the Sustainable Yield Estimator application (SYE). Daily streamflows and the SYE water-use database were used to determine a set of indicators of flow alteration, including percent alteration of August median flow, water-use intensity, and withdrawal and return-flow fraction. The contributing areas to the fish-sampling sites were delineated and used with a Geographic Information System (GIS) to determine a set of environmental characteristics, including elevation, basin slope, percent sand and gravel, percent wetland, and percent open water, and a set of anthropogenic-alteration variables, including impervious cover and dam density. Two analytical techniques, quantile regression and generalized linear modeling, were applied to determine the association between fish-response variables and the selected environmental and

  1. Quality evaluation of fish and other seafood by traditional and nondestructive instrumental methods: Advantages and limitations.

    Science.gov (United States)

    Hassoun, Abdo; Karoui, Romdhane

    2017-06-13

    Although being one of the most vulnerable and perishable products, fish and other seafoods provide a wide range of health-promoting compounds. Recently, the growing interest of consumers in food quality and safety issues has contributed to the increasing demand for sensitive and rapid analytical technologies. Several traditional physicochemical, textural, sensory, and electrical methods have been used to evaluate freshness and authentication of fish and other seafood products. Despite the importance of these standard methods, they are expensive and time-consuming, and often susceptible to large sources of variation. Recently, spectroscopic methods and other emerging techniques have shown great potential due to speed of analysis, minimal sample preparation, high repeatability, low cost, and, most of all, the fact that these techniques are noninvasive and nondestructive and, therefore, could be applied to any online monitoring system. This review describes firstly and briefly the basic principles of multivariate data analysis, followed by the most commonly traditional methods used for the determination of the freshness and authenticity of fish and other seafood products. A special focus is put on the use of rapid and nondestructive techniques (spectroscopic techniques and instrumental sensors) to address several issues related to the quality of these products. Moreover, the advantages and limitations of each technique are reviewed and some perspectives are also given.

  2. Hypoxic areas, density-dependence and food limitation drive the body condition of a heavily exploited marine fish predator

    DEFF Research Database (Denmark)

    Casini, Michele; Käll, Filip; Hansson, Martin

    2016-01-01

    Investigating the factors regulating fish condition is crucial in ecology and the management of exploited fish populations. The body condition of cod (Gadus morhua) in the Baltic Sea has dramatically decreased during the past two decades, with large implications for the fishery relying on this re...

  3. Metabolic factors limiting performance in marathon runners.

    Science.gov (United States)

    Rapoport, Benjamin I

    2010-10-21

    Each year in the past three decades has seen hundreds of thousands of runners register to run a major marathon. Of those who attempt to race over the marathon distance of 26 miles and 385 yards (42.195 kilometers), more than two-fifths experience severe and performance-limiting depletion of physiologic carbohydrate reserves (a phenomenon known as 'hitting the wall'), and thousands drop out before reaching the finish lines (approximately 1-2% of those who start). Analyses of endurance physiology have often either used coarse approximations to suggest that human glycogen reserves are insufficient to fuel a marathon (making 'hitting the wall' seem inevitable), or implied that maximal glycogen loading is required in order to complete a marathon without 'hitting the wall.' The present computational study demonstrates that the energetic constraints on endurance runners are more subtle, and depend on several physiologic variables including the muscle mass distribution, liver and muscle glycogen densities, and running speed (exercise intensity as a fraction of aerobic capacity) of individual runners, in personalized but nevertheless quantifiable and predictable ways. The analytic approach presented here is used to estimate the distance at which runners will exhaust their glycogen stores as a function of running intensity. In so doing it also provides a basis for guidelines ensuring the safety and optimizing the performance of endurance runners, both by setting personally appropriate paces and by prescribing midrace fueling requirements for avoiding 'the wall.' The present analysis also sheds physiologically principled light on important standards in marathon running that until now have remained empirically defined: The qualifying times for the Boston Marathon.

  4. Metabolic factors limiting performance in marathon runners.

    Directory of Open Access Journals (Sweden)

    Benjamin I Rapoport

    2010-10-01

    Full Text Available Each year in the past three decades has seen hundreds of thousands of runners register to run a major marathon. Of those who attempt to race over the marathon distance of 26 miles and 385 yards (42.195 kilometers, more than two-fifths experience severe and performance-limiting depletion of physiologic carbohydrate reserves (a phenomenon known as 'hitting the wall', and thousands drop out before reaching the finish lines (approximately 1-2% of those who start. Analyses of endurance physiology have often either used coarse approximations to suggest that human glycogen reserves are insufficient to fuel a marathon (making 'hitting the wall' seem inevitable, or implied that maximal glycogen loading is required in order to complete a marathon without 'hitting the wall.' The present computational study demonstrates that the energetic constraints on endurance runners are more subtle, and depend on several physiologic variables including the muscle mass distribution, liver and muscle glycogen densities, and running speed (exercise intensity as a fraction of aerobic capacity of individual runners, in personalized but nevertheless quantifiable and predictable ways. The analytic approach presented here is used to estimate the distance at which runners will exhaust their glycogen stores as a function of running intensity. In so doing it also provides a basis for guidelines ensuring the safety and optimizing the performance of endurance runners, both by setting personally appropriate paces and by prescribing midrace fueling requirements for avoiding 'the wall.' The present analysis also sheds physiologically principled light on important standards in marathon running that until now have remained empirically defined: The qualifying times for the Boston Marathon.

  5. Measured elemental transfer factors for boreal hunter/gatherer scenarios: fish, game and berries

    International Nuclear Information System (INIS)

    Sheppard, S.C.; Long, J.M.; Sanipelli, B.

    2010-01-01

    The environmental assessment of long-term nuclear waste management requires data to estimate food chain transfers for radionuclides in various environmental settings. For key elements such as iodine (I) and chlorine (Cl), there is a paucity of transfer factor data, particularly outside of agricultural food chains. This study dealt with transfers of I, Cl and 28 other elements to foods that would be typical of boreal hunter/gatherer lifestyles, as well as being common foods for modern recreational and subsistence hunters. Food/substrate concentration ratios (CRs) and related transfer factors for eight species of widely distributed fish, whitetail deer (Odocoileus virginianus), Canada geese (Branta canadensis) and wild blueberries (Vaccinium myrtilloides) were measured and compared to the literature. Limited data were obtained for caribou (Rangifer tarandus), elk (Cervus elaphus) and moose (Alces americanus). Freshwater sediment Kd values and CRs for a ubiquitous freshwater macrophyte were also obtained. The CRs for I in fish were 29 L kg -1 in edible muscle (fillets) of large-bodied species and 85 L kg -1 for whole, small-bodied fish. The log CRs for fish and macrophytes were correlated across elements. For several elements, the Kds for sediments in deep water were ∼4-fold higher than for littoral samples. The elemental transfers to wild animals for some elements were notably different than the literature indicates for domestic animals. It is argued that the transfer data obtained using indigenous elements from real environmental settings, as opposed to contaminant elements in experimental or impacted environments, are especially relevant to assessment of long-term impacts.

  6. Measured elemental transfer factors for boreal hunter/gatherer scenarios: fish, game and berries

    Energy Technology Data Exchange (ETDEWEB)

    Sheppard, S.C., E-mail: sheppards@ecomatters.co [ECOMatters Inc., WB Lewis Business Centre, 24 Aberdeen Avenue, Pinawa, Manitoba R0E 1L0 (Canada); Long, J.M.; Sanipelli, B. [ECOMatters Inc., WB Lewis Business Centre, 24 Aberdeen Avenue, Pinawa, Manitoba R0E 1L0 (Canada)

    2010-11-15

    The environmental assessment of long-term nuclear waste management requires data to estimate food chain transfers for radionuclides in various environmental settings. For key elements such as iodine (I) and chlorine (Cl), there is a paucity of transfer factor data, particularly outside of agricultural food chains. This study dealt with transfers of I, Cl and 28 other elements to foods that would be typical of boreal hunter/gatherer lifestyles, as well as being common foods for modern recreational and subsistence hunters. Food/substrate concentration ratios (CRs) and related transfer factors for eight species of widely distributed fish, whitetail deer (Odocoileus virginianus), Canada geese (Branta canadensis) and wild blueberries (Vaccinium myrtilloides) were measured and compared to the literature. Limited data were obtained for caribou (Rangifer tarandus), elk (Cervus elaphus) and moose (Alces americanus). Freshwater sediment Kd values and CRs for a ubiquitous freshwater macrophyte were also obtained. The CRs for I in fish were 29 L kg{sup -1} in edible muscle (fillets) of large-bodied species and 85 L kg{sup -1} for whole, small-bodied fish. The log CRs for fish and macrophytes were correlated across elements. For several elements, the Kds for sediments in deep water were {approx}4-fold higher than for littoral samples. The elemental transfers to wild animals for some elements were notably different than the literature indicates for domestic animals. It is argued that the transfer data obtained using indigenous elements from real environmental settings, as opposed to contaminant elements in experimental or impacted environments, are especially relevant to assessment of long-term impacts.

  7. Factors associated with persistent airflow limitation in severe asthma

    NARCIS (Netherlands)

    ten Brinke, A.; Zwinderman, A. H.; Sterk, P. J.; Rabe, K. F.; Bel, E. H.

    2001-01-01

    Persistent airflow limitation can develop in nonsmoking patients with asthma. However, the prevalence and risk factors for airways obstruction with incomplete reversibility in asthma are unknown. We assessed the prevalence of persistent airflow limitation (defined as postbronchodilator FEV(1) or

  8. Concentration factors for 137Cs in Japanese coastal fish (1984-1990)

    International Nuclear Information System (INIS)

    Tateda, Yutaka; Koyanagi, Taku.

    1996-01-01

    Concentration factors (CFs; Bq kg -1 wet in fish muscle/Bq kg -1 in filtered seawater) for 137 Cs were determined in Japanese coastal fish collected from 1984 to 1990. 137 Cs/Cs (stable) atom ratios were also examined to clarify the distribution equilibrium of 137 Cs-between marine fish and seawater. The geometric mean of CF in Japanese coastal fish was 52±4 (standard error of the mean), with values ranging from 14 to 133. 137 Cs/Cs atom ratios both in marine fish and seawater indicate that the distribution of 137 Cs was in equilibrium between fish muscle and seawater. Therefore, CF values obtained in the present study can be regarded as equilibrated. Our results show that the CFs for 137 Cs in Japanese coastal fish were within the range of Japanese guidelines, but were below the recommended IAEA value. (author)

  9. Quantifying environmental limiting factors on tree cover using geospatial data.

    Science.gov (United States)

    Greenberg, Jonathan A; Santos, Maria J; Dobrowski, Solomon Z; Vanderbilt, Vern C; Ustin, Susan L

    2015-01-01

    Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2) How are the ELFs distributed spatially? 3) To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET) and PET minus precipitation (PET-P) as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4) environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

  10. Variable Eddington factors and flux-limiting diffusion coefficients

    International Nuclear Information System (INIS)

    Whalen, P.P.

    1982-01-01

    Variable Eddington factors and flux limiting diffusion coefficients arise in two common techniques of closing the moment equations of transport. The first two moment equations of the full transport equation are still frequently used to solve many problems of radiative or particle transport. An approximate analysis, developed by Levermore, exhibits the relation between the coefficients of the two different techniques. This analysis is described and then used to test the validity of several commonly used flux limiters and Eddington factors. All of the ad-hoc flux limiters have limited validity. All of the variable Eddington factors derived from some underlying description of the angular distribution function are generally valid. The use of coefficients from Minerbo's elegant maximum entropy Eddington factor analysis is suggested for use in either flux limited diffusion or variable Eddington factor equations

  11. Quantifying environmental limiting factors on tree cover using geospatial data.

    Directory of Open Access Journals (Sweden)

    Jonathan A Greenberg

    Full Text Available Environmental limiting factors (ELFs are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1 Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2 How are the ELFs distributed spatially? 3 To what extent are unmeasured environmental factors limiting tree cover? ELFs are difficult to quantify as they require significant sample sizes. We addressed this by using geospatial data over a relatively large spatial extent, where the wall-to-wall sampling ensures the inclusion of rare data points which define the minimum or maximum response to environmental factors. We tested mean temperature, minimum temperature, potential evapotranspiration (PET and PET minus precipitation (PET-P as potential limiting factors on percent tree cover. We found that the study area showed system-wide limitations on tree cover, and each of the factors showed evidence of being limiting on tree cover. However, only 1.2% of the total area appeared to be limited by the four (4 environmental factors, suggesting other unmeasured factors are limiting much of the tree cover in the study area. Where sites were near their theoretical maximum, non-forest sites (tree cover < 25% were primarily limited by cold mean temperatures, open-canopy forest sites (tree cover between 25% and 60% were primarily limited by evaporative demand, and closed-canopy forests were not limited by any particular environmental factor. The detection of ELFs is necessary in order to fully understand the width of limitations that species experience within their geographic range.

  12. Evidence of market-driven size-selective fishing and the mediating effects of biological and institutional factors

    Science.gov (United States)

    Reddy, Sheila M. W.; Wentz, Allison; Aburto-Oropeza, Octavio; Maxey, Martin; Nagavarapu, Sriniketh; Leslie, Heather M.

    2014-01-01

    Market demand is often ignored or assumed to lead uniformly to the decline of resources. Yet little is known about how market demand influences natural resources in particular contexts, or the mediating effects of biological or institutional factors. Here, we investigate this problem by examining the Pacific red snapper (Lutjanus peru) fishery around La Paz, Mexico, where medium or “plate-sized” fish are sold to restaurants at a premium price. If higher demand for plate-sized fish increases the relative abundance of the smallest (recruit size class) and largest (most fecund) fish, this may be a market mechanism to increase stocks and fishermen’s revenues. We tested this hypothesis by estimating the effect of prices on the distribution of catch across size classes using daily records of prices and catch. We linked predictions from this economic choice model to a staged-based model of the fishery to estimate the effects on the stock and revenues from harvest. We found that the supply of plate-sized fish increased by 6%, while the supply of large fish decreased by 4% as a result of a 13% price premium for plate-sized fish. This market-driven size selection increased revenues (14%) but decreased total fish biomass (−3%). However, when market-driven size selection was combined with limited institutional constraints, both fish biomass (28%) and fishermen’s revenue (22%) increased. These results show that the direction and magnitude of the effects of market demand on biological populations and human behavior can depend on both biological attributes and institutional constraints. Fisheries management may capitalize on these conditional effects by implementing size-based regulations when economic and institutional incentives will enhance compliance, as in the case we describe here, or by creating compliance enhancing conditions for existing regulations. PMID:23865225

  13. Evidence of market-driven size-selective fishing and the mediating effects of biological and institutional factors.

    Science.gov (United States)

    Reddy, Sheila M W; Wentz, Allison; Aburto-Oropeza, Octavio; Maxey, Martin; Nagavarapu, Sriniketh; Leslie, Heather M

    2013-06-01

    Market demand is often ignored or assumed to lead uniformly to the decline of resources. Yet little is known about how market demand influences natural resources in particular contexts, or the mediating effects of biological or institutional factors. Here, we investigate this problem by examining the Pacific red snapper (Lutjanus peru) fishery around La Paz, Mexico, where medium or "plate-sized" fish are sold to restaurants at a premium price. If higher demand for plate-sized fish increases the relative abundance of the smallest (recruit size class) and largest (most fecund) fish, this may be a market mechanism to increase stocks and fishermen's revenues. We tested this hypothesis by estimating the effect of prices on the distribution of catch across size classes using daily records of prices and catch. We linked predictions from this economic choice model to a staged-based model of the fishery to estimate the effects on the stock and revenues from harvest. We found that the supply of plate-sized fish increased by 6%, while the supply of large fish decreased by 4% as a result of a 13% price premium for plate-sized fish. This market-driven size selection increased revenues (14%) but decreased total fish biomass (-3%). However, when market-driven size selection was combined with limited institutional constraints, both fish biomass (28%) and fishermen's revenue (22%) increased. These results show that the direction and magnitude of the effects of market demand on biological populations and human behavior can depend on both biological attributes and institutional constraints. Fisheries management may capitalize on these conditional effects by implementing size-based regulations when economic and institutional incentives will enhance compliance, as in the case we describe here, or by creating compliance enhancing conditions for existing regulations.

  14. Hankin and Reeves' approach to estimating fish abundance in small streams: limitations and alternatives

    Science.gov (United States)

    William L. Thompson

    2003-01-01

    Hankin and Reeves' (1988) approach to estimating fish abundance in small streams has been applied in stream fish studies across North America. However, their population estimator relies on two key assumptions: (1) removal estimates are equal to the true numbers of fish, and (2) removal estimates are highly correlated with snorkel counts within a subset of sampled...

  15. Factors affecting the fishing impact on cartilaginous fishes in southeastern Spain (western Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Manuel Mendoza

    2014-03-01

    Full Text Available We propose a global index of impact based on the relative vulnerability of the local population of every species and the further application of regression trees globally optimized with evolutionary algorithms to study the fishing impact on the cartilaginous fish in southeastern Spain. The fishing impact is much higher in areas of less than 40 m depth within 11 km of the Cape Palos marine reserve. The impact also depends on the state of the sea and the kind of habitat. Deep-sea habitats associated with hard substrata and sandy beds show the highest impact, and sublittoral muds and habitats associated with circa littoral rocks with moderate energy show the lowest impact. The fishing impact changes throughout the moon cycle, showing different day-scale patterns associated with different habitats and different species compositions. Finally, we show that the global optimization of the regression trees can be essential to find some important patterns and that these trees are a useful tool for determining which areas are considered to be more important in terms of protection, taking into account specifically the vulnerability of the local populations.

  16. Logistic Regression Analysis on Factors Affecting Adoption of Rice-Fish Farming in North Iran

    Directory of Open Access Journals (Sweden)

    Seyyed Ali NOORHOSSEINI-NIYAKI

    2012-06-01

    Full Text Available We evaluated the factors influencing the adoption of rice-fish farming in the Tavalesh region near the Caspian Sea in northern Iran. We conducted a survey with open-ended questions. Data were collected from 184 respondents (61 adopters and 123 non-adopters randomly sampled from selected villages and analyzed using logistic regression and multi-response analysis. Family size, number of contacts with an extension agent, participation in extension-education activities, membership in social institutions and the presence of farm workers were the most important socio-economic factors for the adoption of rice-fish farming system. In addition, economic problems were the most common issue reported by adopters. Other issues such as lack of access to appropriate fish food, losses of fish, lack of access to high quality fish fingerlings and dehydration and poor water quality were also important to a number of farmers.

  17. Classical limit of diagonal form factors and HHL correlators

    Energy Technology Data Exchange (ETDEWEB)

    Bajnok, Zoltan [MTA Lendület Holographic QFT Group, Wigner Research Centre,H-1525 Budapest 114, P.O.B. 49 (Hungary); Janik, Romuald A. [Institute of Physics, Jagiellonian University,ul. Łojasiewicza 11, 30-348 Kraków (Poland)

    2017-01-16

    We propose an expression for the classical limit of diagonal form factors in which we integrate the corresponding observable over the moduli space of classical solutions. In infinite volume the integral has to be regularized by proper subtractions and we present the one, which corresponds to the classical limit of the connected diagonal form factors. In finite volume the integral is finite and can be expressed in terms of the classical infinite volume diagonal form factors and subvolumes of the moduli space. We analyze carefully the periodicity properties of the finite volume moduli space and found a classical analogue of the Bethe-Yang equations. By applying the results to the heavy-heavy-light three point functions we can express their strong coupling limit in terms of the classical limit of the sine-Gordon diagonal form factors.

  18. Farm-level risk factors for fish-borne zoonotic trematode infection in integrated small-scale fish farms in northern Vietnam.

    Directory of Open Access Journals (Sweden)

    Van Thi Phan

    Full Text Available BACKGROUND: Northern Vietnam is an endemic region for fish-borne zoonotic trematodes (FZT, including liver and intestinal flukes. Humans acquire the FZT infection by eating raw or inadequately cooked fish. The production of FZT-free fish in aquaculture is a key component in establishing a sustainable program to prevent and control the FZT transmission to humans. Interventions in aquaculture should be based on knowledge of the main risk factors associated with FZT transmission. METHODOLOGY/PRINCIPAL FINDINGS: A longitudinal study was carried out from June 2006 to May 2007 in Nam Dinh province, Red River Delta to investigate the development and risk factors of FZT infections in freshwater cultured fish. A total of 3820 fish were sampled six times at two-month intervals from 96 fish farms. Logistic analysis with repeated measurements was used to evaluate potential risk factors based on information collected through questionnaire interviews with 61 fish farm owners. The results showed that the FZT infections significantly increased from first sampling in June to July 2006 (65% to sixth sampling in April to May, 2007 (76%. The liver fluke, Clonorchis sinensis and different zoonotic intestinal flukes including Haplochis pumilio, H. taichui, H. yokogawai, Centrocestus formosanus and Procerovum varium were found in sampled fish. Duration of fish cultured (sampling times, mebendazole drug self-medication of household members, presence of snails in the pond, and feeding fish with green vegetation collected outside fish farms all had a significant effect on the development of FZT prevalence in the fish. CONCLUSIONS/SIGNIFICANCE: The FZT prevalence in fish increased by 11 percentage points during a one-year culture period and the risk factors for the development of infection were identified. Results also highlight that the young fish are already highly infected when stocked into the grow-out systems. This knowledge should be incorporated into control

  19. Critical Success Factors for Limited Service Hotels in Malaysia

    OpenAIRE

    Wong, Chee Keng

    2015-01-01

    Critical success factors were used originally in Information technology areas when it was first introduced but has since been applied generically in other industries. This study explores the critical success factors for limited service hotels in Malaysia from both customer and hotel operator/ business owners’ perspective. The literature presents information from tourism in general and in Malaysia, definition of limited service hotels and its relevance to the hospitality industry in Malaysia, ...

  20. VARIOUS FACTORS AFFECTING DRESSING PERCENTAGE OF COMMERCIALLY CULTURED CYPRINID FISH IN CARP FISH PONDS IN SERBIA

    Directory of Open Access Journals (Sweden)

    Todor Marković

    2012-12-01

    Full Text Available The aim of this study was to determine the yield carcass of all categories of cyprinid fish reared in ponds in Serbia. Samples of two and three-year old carp, two-year old silver carp and grass carp were taken in the winter from a pond where the production is organized in a semi­intensive system. The three­year old carp was sampled from two ponds. In one case, it fed on barley, maize and wheat in the following proportions 40:30:30, while in the second case it fed on complete diet mixtures. Also, the samples of two­year old carp were taken from ponds where they fed on complete feed mixture. Dressing percentage was the most favourable in common carp (67%, followed by silver carp (62%, and it was the least in grass carp (60% (p<0.01. The best yield (66% was obtained in two-year old carp, followed by one-year old carp (64%, and the worst yield was determined in three-year old carp (58% (p<0.01. Carcasses yield was better in two-year old carp fed on pelleted feed (68% than in carp of the same age fed on grains (66% (p<0.01. The values of dressing percentage measured in three-year old carp reared in the semi-intensive system was 56%, and 59% in three-year old carp fed on pelleted complete feed mixture. Fish species, age, system of husbandry and diet showed a significant effect on carcasses yield. The highest dressing percentage and weight of fillets was noted in two-year old carp fed on complete feed, and it was a result of lower weight of internal organs and associated fat. The obtained results may be helpful in creating the best strategy for the selection of raw fish for fish manufacturing.

  1. Factors Affecting Fish Production and Fishing Quality in New Reservoirs, with Guidance on Timber Clearing, Basin Preparation, and Filling.

    Science.gov (United States)

    1981-08-01

    filling and site preparation exist. Knowledge of what the controlling factors are, how they function, and whether they can be manipulated is essential...protection from water- skiers and speedboaters (Jenkins 1970c). Fish food organisms 55. Submerged structures in the littoral zone of reservoirs often are...tolerance 78. Knowledge of the tolerance of terrestrial vegetation to inun- dation is essential to management of "green-tree reservoirs"--i.e., reservoirs

  2. Limiting Size of Fish Fillets at the Center of the Plate Improves the Sustainability of Aquaculture Production

    Directory of Open Access Journals (Sweden)

    Stephen F. Cross

    2011-07-01

    Full Text Available North American dining customers like to have a singular large piece of protein in the center of the plate. When fish is the protein of choice, the portion size from many species is limited by the overall size of the fish. Therefore, for these species, the means to achieve a singular larger portion of “center of the plate” protein is to grow a larger animal. However, fish become less efficient in converting feed to protein as they age. A second option would be to provide two smaller fillets originating from younger, more efficient fish. Here, the sustainability ramifications of these two protein provisioning strategies (single large or two small fillets are considered for three species of fish produced in aquaculture. Growth data for channel catfish (Ictalurus punctatus produced in ponds, rainbow trout (Oncorhynchus mykiss in raceways, and sablefish (Anoplopoma fimbria in marine net pens, were modeled to assess the total biomass and overall food conversion ratio for the production of small, medium or large fish. The production of small fish added an additional 50% or more biomass per year for trout, catfish, and sablefish compared to the production of large fish. Feed conversion ratios were also improved by nearly 10% for the smaller compared to larger fish of each species. Thus, even though all of these species tend to be considered aquaculture species of low environmental impact (and hence “green” or sustainable options, the product form requested by retailers and served by chefs can further increase the sustainability of these species.

  3. Environmental factors affecting large-bodied coral reef fish assemblages in the Mariana Archipelago.

    Directory of Open Access Journals (Sweden)

    Benjamin L Richards

    Full Text Available Large-bodied reef fishes represent an economically and ecologically important segment of the coral reef fish assemblage. Many of these individuals supply the bulk of the reproductive output for their population and have a disproportionate effect on their environment (e.g. as apex predators or bioeroding herbivores. Large-bodied reef fishes also tend to be at greatest risk of overfishing, and their loss can result in a myriad of either cascading (direct or indirect trophic and other effects. While many studies have investigated habitat characteristics affecting populations of small-bodied reef fishes, few have explored the relationship between large-bodied species and their environment. Here, we describe the distribution of the large-bodied reef fishes in the Mariana Archipelago with an emphasis on the environmental factors associated with their distribution. Of the factors considered in this study, a negative association with human population density showed the highest relative influence on the distribution of large-bodied reef fishes; however, depth, water temperature, and distance to deep water also were important. These findings provide new information on the ecology of large-bodied reef fishes can inform discussions concerning essential fish habitat and ecosystem-based management for these species and highlight important knowledge gaps worthy of additional research.

  4. Comparison of the Condition Factor of Five Fish Species of the Araguaia River Basin, Central Brazil

    Directory of Open Access Journals (Sweden)

    Bruno Bastos Gonçalves

    2016-06-01

    Full Text Available This study aims to assess the condition factor (K of five fish species (Serrasalmus rhombeus, Psectrogaster amazonica, Loricaria cataphracta, Panaque nigrolineatus and Squaliforma emarginata. Samplings were conducted during the low-water period of 2007 and 2008 using gillnets and minnow traps. All equipments were placed along a stretch of 1000 m at 5 pm and retrieved at 7 am. Collected fish were taxonomically identified, weighed (g and measured (standard length; mm. The fish fitness was assessed by the condition factor (K=W/L³ and compared among groups of tributaries by a Kruskal-Wallis test. From the five species considered, two (S. emarginata and P. amazonica displayed significant differences of the condition factor among the groups of tributaries. The highest values of K correspond to fish located in the headwaters, while lowest values are observed in tributaries located in the floodplain.

  5. Thermoelectric Power Factor Limit of a 1D Nanowire

    Science.gov (United States)

    Chen, I.-Ju; Burke, Adam; Svilans, Artis; Linke, Heiner; Thelander, Claes

    2018-04-01

    In the past decade, there has been significant interest in the potentially advantageous thermoelectric properties of one-dimensional (1D) nanowires, but it has been challenging to find high thermoelectric power factors based on 1D effects in practice. Here we point out that there is an upper limit to the thermoelectric power factor of nonballistic 1D nanowires, as a consequence of the recently established quantum bound of thermoelectric power output. We experimentally test this limit in quasiballistic InAs nanowires by extracting the maximum power factor of the first 1D subband through I -V characterization, finding that the measured maximum power factors conform to the theoretical limit. The established limit allows the prediction of the achievable power factor of a specific nanowire material system with 1D electronic transport based on the nanowire dimension and mean free path. The power factor of state-of-the-art semiconductor nanowires with small cross section and high crystal quality can be expected to be highly competitive (on the order of mW /m K2 ) at low temperatures. However, they have no clear advantage over bulk materials at, or above, room temperature.

  6. Quantifying Environmental Limiting Factors on Tree Cover Using Geospatial Data

    NARCIS (Netherlands)

    Greenberg, Jonathan; Ferreira Dos Santos, Maria Joao; Dobrowski, Solomon; Vanderbilt, Vern; Ustin, Susan

    2015-01-01

    Environmental limiting factors (ELFs) are the thresholds that determine the maximum or minimum biological response for a given suite of environmental conditions. We asked the following questions: 1) Can we detect ELFs on percent tree cover across the eastern slopes of the Lake Tahoe Basin, NV? 2)

  7. The Value and limitations of various approaches to the monitoring of water quality for freshwater fish

    National Research Council Canada - National Science Library

    1978-01-01

    ... tolerated by fish are known with some accuracy. Studies have shown that, for many contaminants, the water quality requirements for freshwater fisheries are more demanding than those for potable water...

  8. Maternal fish consumption, fatty acid levels and angiogenic factors: The Generation R Study

    NARCIS (Netherlands)

    P.K. Bautista-Niño (Paula); M.J. Tielemans (Myrte); S. Schalekamp-Timmermans (Sarah); J.C.J. Steenweg-de Graaff (Jolien); A. Hofman (Albert); H.W. Tiemeier (Henning); V.W.V. Jaddoe (Vincent); E.A.P. Steegers (Eric); J.F. Felix (Janine); O.H. Franco (Oscar)

    2015-01-01

    textabstractIntroduction Angiogenic factors, such as placental growth factor (PlGF) and soluble Flt-1 (sFlt-1), are key regulators of placental vascular development. Evidence from in vitro studies indicates that fatty acids can affect angiogenesis. We investigated the associations of maternal fish

  9. Host Cell Restriction Factors that Limit Influenza A Infection

    Directory of Open Access Journals (Sweden)

    Fernando Villalón-Letelier

    2017-12-01

    Full Text Available Viral infection of different cell types induces a unique spectrum of host defence genes, including interferon-stimulated genes (ISGs and genes encoding other proteins with antiviral potential. Although hundreds of ISGs have been described, the vast majority have not been functionally characterised. Cellular proteins with putative antiviral activity (hereafter referred to as “restriction factors” can target various steps in the virus life-cycle. In the context of influenza virus infection, restriction factors have been described that target virus entry, genomic replication, translation and virus release. Genome wide analyses, in combination with ectopic overexpression and/or gene silencing studies, have accelerated the identification of restriction factors that are active against influenza and other viruses, as well as providing important insights regarding mechanisms of antiviral activity. Herein, we review current knowledge regarding restriction factors that mediate anti-influenza virus activity and consider the viral countermeasures that are known to limit their impact. Moreover, we consider the strengths and limitations of experimental approaches to study restriction factors, discrepancies between in vitro and in vivo studies, and the potential to exploit restriction factors to limit disease caused by influenza and other respiratory viruses.

  10. Factors limiting heterotrophic bacterial production in the southern Pacific Ocean

    Directory of Open Access Journals (Sweden)

    F. Van Wambeke

    2008-05-01

    Full Text Available The role of potential factors limiting bacterial growth was investigated along vertical and longitudinal gradients across the South Eastern Pacific Gyre. The effects of glucose, nitrate, ammonium and phosphate additions on heterotrophic bacterial production (using leucine technique were studied in parallel in unfiltered seawater samples incubated under natural daily irradiance. The enrichments realized on the subsurface showed three types of responses. From 141° W (Marquesas plateau to approx 125° W, bacteria were not bottom-up controlled, as confirmed by the huge potential of growth in non-enriched seawater (median of enhancement factor×39 in 24 h. Within the Gyre (125° W–95° W, nitrogen alone stimulated leucine incorporation rates (median×4.2, but rapidly labile carbon (glucose became a second limiting factor (median×37 when the two elements were added. Finally from the border of the gyre to the Chilean upwelling (95° W–73° W, labile carbon was the only factor stimulating heterotrophic bacterial production. Interaction between phytoplankton and heterotrophic bacterial communities and the direct versus indirect effect of iron and macronutrients on bacterial production were also investigated in four selected sites: two sites on the vicinity of the Marquesas plateau, the centre of the gyre and the Eastern border of the gyre. Both phytoplankton and heterotrophic bacteria were limited by availability of nitrogen within the gyre, but not by iron. Iron limited phytoplankton at Marquesas plateau and at the eastern border of the gyre. However 48 h enrichment experiments were not sufficient to show any clear limitation of heterotrophic bacteria within Marquesas plateau and showed a limitation of these organisms by labile carbon in the eastern border of the Gyre.

  11. White fish reduces cardiovascular risk factors in patients with metabolic syndrome: the WISH-CARE study, a multicenter randomized clinical trial.

    Science.gov (United States)

    Vázquez, C; Botella-Carretero, J I; Corella, D; Fiol, M; Lage, M; Lurbe, E; Richart, C; Fernández-Real, J M; Fuentes, F; Ordóñez, A; de Cos, A I; Salas-Salvadó, J; Burguera, B; Estruch, R; Ros, E; Pastor, O; Casanueva, F F

    2014-03-01

    Reduction of cardiovascular risk with high consumption of fish in diet is still a matter of debate, and concerns about heavy metal contamination have limited consumption of oily fish. We aimed to evaluate the effect of regular ingestion of white fish on cardiovascular risk factors in patients with metabolic syndrome. Multicenter randomized crossover clinical trial including 273 individuals with metabolic syndrome. An 8-week only-one dietary intervention: 100 g/d of white fish (Namibia hake) with advice on a healthy diet, compared with no fish or seafood with advice on a healthy diet. Outcomes were lipid profile, individual components of the metabolic syndrome, serum insulin concentrations, homeostasis model of insulin resistance, serum C-reactive protein and serum fatty acid levels. We found a significant lowering effect of the intervention with white fish on waist circumference (P rise (P syndrome, regular consumption of hake reduces LDL cholesterol concentrations, waist circumference and blood pressure components of the metabolic syndrome. White Fish for Cardiovascular Risk Factors in Patients with Metabolic Syndrome Study, Registered under ClinicalTrials.gov Identifier: NCT01758601. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Lake variability: Key factors controlling mercury concentrations in New York State fish

    International Nuclear Information System (INIS)

    Simonin, Howard A.; Loukmas, Jefferey J.; Skinner, Lawrence C.; Roy, Karen M.

    2008-01-01

    A 4 year study surveyed 131 lakes across New York State beginning in 2003 to improve our understanding of mercury and gather information from previously untested waters. Our study focused on largemouth and smallmouth bass, walleye and yellow perch, common piscivorous fish shown to accumulate high mercury concentrations and species important to local fisheries. Fish from Adirondack and Catskill Forest Preserve lakes generally had higher mercury concentrations than those from lakes in other areas of the state. Variability between nearby individual lakes was observed, and could be due to differences in water chemistry, lake productivity or the abundance of wetlands in the watershed. We found the following factors impact mercury bioaccumulation: fish length, lake pH, specific conductivity, chlorophyll a, mercury concentration in the water, presence of an outlet dam and amount of contiguous wetlands. - Lake water chemistry variables, dams, and wetlands play major roles in determining fish mercury concentrations

  13. Not finding Nemo: limited reef-scale retention in a coral reef fish

    KAUST Repository

    Nanninga, Gerrit B.

    2015-02-03

    The spatial scale of larval dispersal is a key predictor of marine metapopulation dynamics and an important factor in the design of reserve networks. Over the past 15 yr, studies of larval dispersal in coral reef fishes have generated accumulating evidence of consistently high levels of self-recruitment and local retention at various spatial scales. These findings have, to a certain degree, created a paradigm shift toward the perception that large fractions of locally produced recruitment may be the rule rather than the exception. Here we examined the degree of localized settlement in an anemonefish, Amphiprion bicinctus, at a solitary coral reef in the central Red Sea by integrating estimates of self-recruitment obtained from genetic parentage analysis with predictions of local retention derived from a biophysical dispersal model parameterized with real-time physical forcing. Self-recruitment at the reef scale (c. 0.7 km2) was virtually absent during two consecutive January spawning events (1.4 % in 2012 and 0 % in 2013). Predicted levels of local retention at the reef scale varied temporally, but were comparatively low for both simulations (7 % in 2012 and 0 % in 2013). At the same time, the spatial scale of simulated dispersal was restricted to approximately 20 km from the source. Model predictions of reef-scale larval retention were highly dependent on biological parameters, underlining the need for further empirical validations of larval traits over a range of species. Overall, our findings present an urgent caution when assuming the potential for self-replenishment in small marine reserves.

  14. Statistical Hot Channel Factors and Safety Limit CHFR/OFIR

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Byeonghee; Park, Suki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    The fuel integrity of research reactors are usually judged by comparing the critical heat flux ratio (CHFR) and the maximum fuel temperature (MFT) with the safety limits. Onset of flow instability ratio (OFIR) can also be used for the examination with CHFR. Hot channel factors (HCFs) are incorporated when calculating the CHFR/OFIR and MFT, to consider the uncertainties of fuel properties and thermo-hydraulic variables affecting them. The HCFs and safety limit CHFR is sometimes estimated to include too much conservatism, deteriorating the design flexibilities and operating margins. In this paper, a statistical estimation of HCFs and the safety limit CHFR/OFIR is presented by a random sampling of uncertainty parameters. A 15MW pool type research reactor is selected as the sample reactor for the estimation. The HCFs and the safety limit CHFR/OFIR of a 15MW pool type research reactor are evaluated statistically. The parameters affecting the HCF and the safety limit CHFR/OFIR are listed and their uncertainties are estimated. The relevant parameter uncertainties are sampled randomly and the HCFs and the safety limits are evaluated from them. The HCFs and the safety limit CHFR/OFIR with 95% probability are smaller than those estimated deterministically because the statistical evaluation convolute the correlation uncertainties and the other uncertainties in probabilistic way, whereas the deterministic evaluation simply multiply them.

  15. Bioaccumulation of radiocesium by fish: the influence of physicochemical factors and trophic structure

    International Nuclear Information System (INIS)

    Rowan, D.J.; Rasmussen, J.B.

    1994-01-01

    Although many measurements have been made on radiocesium levels in water and aquatic biota, no agreement has been reached regarding the factors affecting bioaccumulation of these radionuclides. With monitoring data from countries that operate nuclear facilities and data from the primary literature, we explored the chemical and ecological factors that determine the bioaccumulation of radiocesium. Using log-linear regression we found that the bioaccumulation of 137 CS by fish was a negative function of both dissolved potassium and suspended sediment concentration, and a positive function of temperature. Important ecological factors were the trophic level of the fish (piscivores bioaccumulate more than planktivores and benthivores), and the length of the food chain as reflected by the ratio of piscivore yield relative to net primary production. Fish from softwater drainages, which make up a large portion of northern Europe and Canada, are more vulnerable to radiocesium contamination than fish from hardwater sedimentary drainages, because these waters are extremely low in potassium and suspended sediment, and their watersheds are less efficient in retaining radiocesium. High dissolved potassium, short food chains, and the much greater volume and mixing potential of the ocean make marine fish less vulnerable to releases of radiocesium. (author)

  16. Massive three-loop form factor in the planar limit

    Energy Technology Data Exchange (ETDEWEB)

    Henn, Johannes [PRISMA Cluster of Excellence, Johannes Gutenberg University,Staudingerweg 9, 55099 Mainz (Germany); Smirnov, Alexander V. [Research Computing Center, Moscow State University,119991 Moscow (Russian Federation); Smirnov, Vladimir A. [Skobeltsyn Institute of Nuclear Physics of Moscow State University,119991 Moscow (Russian Federation); Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology (KIT),Wolfgang-Gaede Straße 1, 76128 Karlsruhe (Germany); Steinhauser, Matthias [Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology (KIT),Wolfgang-Gaede Straße 1, 76128 Karlsruhe (Germany)

    2017-01-17

    We compute the three-loop QCD corrections to the massive quark-anti-quark-photon form factors F{sub 1} and F{sub 2} in the large-N{sub c} limit. The analytic results are expressed in terms of Goncharov polylogarithms. This allows for a straightforward numerical evaluation. We also derive series expansions, including power suppressed terms, for three kinematic regions corresponding to small and large invariant masses of the photon momentum, and small velocities of the heavy quarks.

  17. Characteristic Features and Contributory Factors in Fatal Ciguatera Fish Poisoning—Implications for Prevention and Public Education

    Science.gov (United States)

    Chan, Thomas Y. K.

    2016-01-01

    In this review, the main objective was to describe the characteristic features of fatal ciguatera fish poisoning and identify contributory factors, with a view to promote prevention and public education. Ciguatera-related deaths, although rare, have been reported from the Pacific, Caribbean, and Indian Ocean regions. The clinical features were generally dominated by convulsions and coma, with various focal neurological signs. Several contributory factors could be identified, including consumption of ciguatoxin (CTX)-rich fish parts (viscera and head) in larger amounts, the most ciguatoxic fish species (e.g., Gymnothorax flavimarginatus) and reef fish collected after storms and individuals' susceptibility. Mass ciguatera fish poisoning with mortalities also occurred when G. flavimarginatus and other ciguatoxic fish species were shared in gatherings and parties. The characteristic features of fatal ciguatera fish poisoning must be recognized early. The public should be repeatedly reminded to avoid eating the most ciguatoxic fish species and the CTX-rich parts of reef fish. To prevent mass poisoning in gatherings and parties, the most ciguatoxic fish species and potentially toxic fish species must be avoided. Particularly after hits by disastrous storms, it is important to monitor the toxicity of reef fish and the incidence rates of ciguatera. PMID:26787145

  18. Characteristic Features and Contributory Factors in Fatal Ciguatera Fish Poisoning--Implications for Prevention and Public Education.

    Science.gov (United States)

    Chan, Thomas Y K

    2016-04-01

    In this review, the main objective was to describe the characteristic features of fatal ciguatera fish poisoning and identify contributory factors, with a view to promote prevention and public education. Ciguatera-related deaths, although rare, have been reported from the Pacific, Caribbean, and Indian Ocean regions. The clinical features were generally dominated by convulsions and coma, with various focal neurological signs. Several contributory factors could be identified, including consumption of ciguatoxin (CTX)-rich fish parts (viscera and head) in larger amounts, the most ciguatoxic fish species (e.g.,Gymnothorax flavimarginatus) and reef fish collected after storms and individuals' susceptibility. Mass ciguatera fish poisoning with mortalities also occurred when G. flavimarginatus and other ciguatoxic fish species were shared in gatherings and parties. The characteristic features of fatal ciguatera fish poisoning must be recognized early. The public should be repeatedly reminded to avoid eating the most ciguatoxic fish species and the CTX-rich parts of reef fish. To prevent mass poisoning in gatherings and parties, the most ciguatoxic fish species and potentially toxic fish species must be avoided. Particularly after hits by disastrous storms, it is important to monitor the toxicity of reef fish and the incidence rates of ciguatera. © The American Society of Tropical Medicine and Hygiene.

  19. Influence of environmental factors on fish assemblages in streams of the Elbe and Oder basins

    Directory of Open Access Journals (Sweden)

    Luboš Kůra

    2015-11-01

    Full Text Available The effects of environmental parameters on changes in the structure of fish assemblages were studied in the Elbe and the Odra basin. Research was done at 819 sites surveyed in the field during the period 1993-2007. The impact of 46 factors derived from the maps through a GIS was tested as well as the impact of 10 factors recognized in the field. To evaluate the influence of these factors the indirect (DCA and direct (CCA multivariate cluster analysis were used. Analyses were performed with data on presence-absence and relative abundance of each species. DCA well reflects changes in assemblages in the longitudinal profile of streams. CCA refers to a significant influence of regional and temporal variability and influence of individual factors. The fish assemblages are best characterized by distance from the source location, stream slope, altitude of locality, representation of arable land in the basin, number of ponds in the sub-basin above the locality, type of waters (salmonid or cyprinid, and water temperature (the only of the parameters of the field. The analyzed factors better reflect the variability in fish assemblages of the Odra than of Elbe river basin. The analysis showed good practical efficiency of processing information from a large sample of data from ichthyological surveys. The tools of GIS and the use of statistical methods make possible to characterize basic ecological requirements of most species and specify conditions determining specific composition of fish assemblages.

  20. Worldwide patterns of fish biodiversity in estuaries: Effect of global vs. local factors

    Science.gov (United States)

    Pasquaud, Stéphanie; Vasconcelos, Rita P.; França, Susana; Henriques, Sofia; Costa, Maria José; Cabral, Henrique

    2015-03-01

    The main ecological patterns and the functioning of estuarine ecosystems are difficult to evaluate due to natural and human induced complexity and variability. Broad geographical approaches appear particularly useful. This study tested, at a worldwide scale, the influence of global and local variables in fish species richness in estuaries, aiming to determine the latitudinal pattern of species richness, and patterns which could be driven by local features such as estuary area, estuary mouth width, river flow and intertidal area. Seventy one estuarine systems were considered with data obtained from the literature and geographical information system. Correlation tests and generalized linear models (GLM) were used in data analyses. Species richness varied from 23 to 153 fish species. GLM results showed that estuary area was the most important factor explaining species richness, followed by latitude and mouth width. Species richness increased towards the equator, and higher values were found in larger estuaries and with a wide mouth. All these trends showed a high variability. A larger estuary area probably reflects a higher diversity of habitats and/or productivity, which are key features for estuarine ecosystem functioning and biota. The mouth width effect is particularly notorious for marine and diadromous fish species, enhancing connectivity between marine and freshwater realms. The effects of river flow and intertidal area on the fish species richness appear to be less evident. These two factors may have a marked influence in the trophic structure of fish assemblages.

  1. Influence of environmental factors on fish production in Ogun-State ...

    African Journals Online (AJOL)

    The study investigated environmental factors influencing fish farming in Ijebu - Ode Local Government Area (LGA) of Ogun-state, Nigeria. Data were obtained from 50 respondents selected from 10 ponds in the area of study. Respondents were selected for the study using random sampling technique while the ponds ...

  2. LIMITING FACTORS FOR THE DEVELOPMENT OF THE SERBIAN HOSPITALITY INDUSTRY

    Directory of Open Access Journals (Sweden)

    Nikolina Kosar

    2016-12-01

    Full Text Available Heterogeneity and complexity determine multidisciplinary approach to the hospitality research. Identification and analysis of limited hospitality development factors imply very complex scientific approach. Case study methodology is applied on Republic of Serbia, which is transition country and candidate for EU accession. Research results identified key factors which had impact on lag, stagnation and contemporary level of hospitality development. Firstly, way of executed privatization process of hospitality companies in Serbia i.e. only ownership transformation, as part of business transformation, was done (organizational, management, technological, financial and human resources parts of business transformation didn’t implement. Secondly, non-acceptable terms and conditions of credit lines for financing privatization and future business of privatized hospitality companies. Furthermore, buyers of privatized hospitality companies didn’t prepared adequate projections of cash flow and sources of financing (owned and borrowed. Finally, technological development and human resources were result of the first mentioned limited factor. In order to improve business in hospitality industry in transition economies, all stakeholders should be involved. State should improve business environment. Educational institutions should create applicable programs on market. Investors should be ready to invest in technological and human resource development. Banks should implement the best financing practice from headquarters in EU.

  3. Factors affecting haematological indices in free-living fish populations

    Czech Academy of Sciences Publication Activity Database

    Lusková, Věra

    1998-01-01

    Roč. 67, č. 4 (1998), s. 249-255 ISSN 0001-7213. [International ichthyohaematology conference /5./. Protivín, 30.11.1998-03.12.1998] R&D Projects: GA ČR GA514/95/0203; GA AV ČR IAA6087704 Subject RIV: EH - Ecology, Behaviour Impact factor: 0.288, year: 1998 http://vfu-www.vfu.cz/acta-vet/vol67/249-98.htm

  4. Hankin and Reeves' Approach to Estimating Fish Abundance in Small Streams : Limitations and Potential Options.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, William L. [Bonneville Power Administration, Portland, OR (US). Environment, Fish and Wildlife

    2000-11-01

    Hankin and Reeves' (1988) approach to estimating fish abundance in small streams has been applied in stream-fish studies across North America. However, as with any method of population estimation, there are important assumptions that must be met for estimates to be minimally biased and reasonably precise. Consequently, I investigated effects of various levels of departure from these assumptions via simulation based on results from an example application in Hankin and Reeves (1988) and a spatially clustered population. Coverage of 95% confidence intervals averaged about 5% less than nominal when removal estimates equaled true numbers within sampling units, but averaged 62% - 86% less than nominal when they did not, with the exception where detection probabilities of individuals were >0.85 and constant across sampling units (95% confidence interval coverage = 90%). True total abundances averaged far (20% - 41%) below the lower confidence limit when not included within intervals, which implies large negative bias. Further, average coefficient of variation was about 1.5 times higher when removal estimates did not equal true numbers within sampling units (C{bar V} = 0.27 [SE = 0.0004]) than when they did (C{bar V} = 0.19 [SE = 0.0002]). A potential modification to Hankin and Reeves' approach is to include environmental covariates that affect detection rates of fish into the removal model or other mark-recapture model. A potential alternative is to use snorkeling in combination with line transect sampling to estimate fish densities. Regardless of the method of population estimation, a pilot study should be conducted to validate the enumeration method, which requires a known (or nearly so) population of fish to serve as a benchmark to evaluate bias and precision of population estimates.

  5. Environmental factors predicting fish community structure in two neotropical rivers in Brazil

    Directory of Open Access Journals (Sweden)

    Yzel Rondon Súarez

    Full Text Available In order to assess the organization patterns of the fish communities in the Jogui and Iguatemi rivers, we collected fish with gill nets tri-monthly from November 1999 to August 2000. Hypostomus ancistroides and Parauchenipterus galeatus were the most abundant species in the Jogui and Iguatemi rivers, respectively. Longitudinal variation was more important than seasonal in determining the species composition in both rivers, and the difference between seasons was not statistically significant. Altitude was the most important factor determining species distribution.

  6. Derived concentration factors for caesium-137 in edible species of North Sea fish

    International Nuclear Information System (INIS)

    Steele, A.K.

    1990-01-01

    Concentration factor (CF=Bq kg -1 fillet/Bg kg -1 filtered sea water) values for 137 Cs in fillets of cod (Gadus morhua), haddock (Merlanogrammus aeglefinus), plaice (Pleuronectes platessa) and whiting (Merlangius merlangius), were derived from fish and filtered seawater concentrations. Samples were collected in twelve sampling boxes in the North Sea over an eight-year period - 1978-1985. The range of results with species, between species, and between surveys are discussed. Mean CF values of 92, 58, 39 and 150 were found in cod, haddock, plaice and whiting respectively. These support the International Atomic Energy Authority recommended CF value of 100 for fish in generalised dose assessments. (author)

  7. Concentration factors of stable elements and radionuclides in Po river fish

    International Nuclear Information System (INIS)

    Achilli, M.; Ciceri, G.; Bozzani, A.; Guzzi, L.; Queirazza, G.

    1988-01-01

    The concentration factors (CF) of stable Co, Cs, Mn, Fe, Zn and Sr in different fish from six stretches in the middle course of the Po river (N. Italy) have been investigated. The space-time variation in water has been followed for 14 months. The investigation has been undertaken to study CF variations in the same fish species as a function of the physico-chemical form of the different elements in water (dissolved, dissolved and exchangeable fraction of the particulate, total). CF values of 103 Ru, 131 I and 134 - 137 Cs were also investigated for Cyprinus carpio reared, with artificial food, in two semi-natural environments

  8. Limiting factors in the production of deep microstructures

    Science.gov (United States)

    Tolfree, David W. L.; O'Neill, William; Tunna, Leslie; Sutcliffe, Christopher

    1999-10-01

    Microsystems increasingly require precision deep microstructures that can be cost-effectively designed and manufactured. New products must be able to meet the demands of the rapidly growing markets for microfluidic, micro- optical and micromechanical devices in industrial sectors which include chemicals, pharmaceuticals, biosciences, medicine and food. The realization of such products, first requires an effective process to design and manufacture prototypes. Two process methods used for the fabrication of high aspect-ratio microstructures are based on X-ray beam lithography with electroforming processes and direct micromachining with a frequency multiplied Nd:YAG laser using nanosecond pulse widths. Factors which limit the efficiency and precision obtainable using such processes are important parameters when deciding on the best fabrication method to use. A basic microstructure with narrow channels suitable for a microfluidic mixer have been fabricated using both these techniques and comparisons made of the limitations and suitability of the processes in respect of fast prototyping and manufacture or working devices.

  9. Limits to the reliability of size-based fishing status estimation for data-poor stocks

    DEFF Research Database (Denmark)

    Kokkalis, Alexandros; Thygesen, Uffe Høgsbro; Nielsen, Anders

    2015-01-01

    For stocks which are considered “data-poor” no knowledge exist about growth, mortality or recruitment. The only available information is from catches. Here we examine the ability to assess the level of exploitation of a data-poor stock based only on information of the size of individuals in catches....... The model is a formulation of the classic Beverton–Holt theory in terms of size where stock parameters describing growth, natural mortality, recruitment, etc. are determined from life-history invariants. A simulation study was used to compare the reliability of assessments performed under different...... to a considerable improvement in the assessment. Overall, the simulation study demonstrates that it may be possible to classify a data-poor stock as undergoing over- or under-fishing, while the exact status, i.e., how much the fishing mortality is above or below Fmsy, can only be assessed with a substantial...

  10. Radiation pressure acceleration: The factors limiting maximum attainable ion energy

    Energy Technology Data Exchange (ETDEWEB)

    Bulanov, S. S.; Esarey, E.; Schroeder, C. B. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Bulanov, S. V. [KPSI, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 (Japan); A. M. Prokhorov Institute of General Physics RAS, Moscow 119991 (Russian Federation); Esirkepov, T. Zh.; Kando, M. [KPSI, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 (Japan); Pegoraro, F. [Physics Department, University of Pisa and Istituto Nazionale di Ottica, CNR, Pisa 56127 (Italy); Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Department, University of California, Berkeley, California 94720 (United States)

    2016-05-15

    Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it transparent for radiation and effectively terminating the acceleration. The off-normal incidence of the laser on the target, due either to the experimental setup, or to the deformation of the target, will also lead to establishing a limit on maximum ion energy.

  11. Physiological and ecological factors influencing the radiocaesium contamination of fish species from Kiev reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Koulikov, A.O. [A.N. Severtzov Institute of Evolutionary Morphology and Ecology of Animals, Russian Academy of Sciences, Moscow (Russian Federation)

    1995-11-23

    The monitoring of {sup 137}Cs contamination of fish from the northern part of the Kiev reservoir between 1987 and 1992 indicated systematic differences in the long-term average contamination levels of different species, which are closely related to their trophic levels. The average contamination of the predatory species: perch (Perca fluviatilis) and pike (Esox lucius) were roughly factors of 6.3 and 4.4 respectively, higher than those of the nonpredatory species: bream (Abramis brama), silver bream (Blicca bjoerkna) and rudd (Scardinius erythrophothalmus). For tench (Tinca tinca) and goldfish (Carassius sp.), this factor is 2. The solution of the caesium balance equation in fish obtained for equilibrium conditions, which is applicable to the long-term contamination, provides some explanations for these accumulation differences between the species with respect to influences by different ecological and physiological factors.

  12. Individual-based analyses reveal limited functional overlap in a coral reef fish community.

    Science.gov (United States)

    Brandl, Simon J; Bellwood, David R

    2014-05-01

    Detailed knowledge of a species' functional niche is crucial for the study of ecological communities and processes. The extent of niche overlap, functional redundancy and functional complementarity is of particular importance if we are to understand ecosystem processes and their vulnerability to disturbances. Coral reefs are among the most threatened marine systems, and anthropogenic activity is changing the functional composition of reefs. The loss of herbivorous fishes is particularly concerning as the removal of algae is crucial for the growth and survival of corals. Yet, the foraging patterns of the various herbivorous fish species are poorly understood. Using a multidimensional framework, we present novel individual-based analyses of species' realized functional niches, which we apply to a herbivorous coral reef fish community. In calculating niche volumes for 21 species, based on their microhabitat utilization patterns during foraging, and computing functional overlaps, we provide a measurement of functional redundancy or complementarity. Complementarity is the inverse of redundancy and is defined as less than 50% overlap in niche volumes. The analyses reveal extensive complementarity with an average functional overlap of just 15.2%. Furthermore, the analyses divide herbivorous reef fishes into two broad groups. The first group (predominantly surgeonfishes and parrotfishes) comprises species feeding on exposed surfaces and predominantly open reef matrix or sandy substrata, resulting in small niche volumes and extensive complementarity. In contrast, the second group consists of species (predominantly rabbitfishes) that feed over a wider range of microhabitats, penetrating the reef matrix to exploit concealed surfaces of various substratum types. These species show high variation among individuals, leading to large niche volumes, more overlap and less complementarity. These results may have crucial consequences for our understanding of herbivorous processes on

  13. Quantitative assessment of a data-limited recreational bonefish fishery using a time-series of fishing guides reports.

    Directory of Open Access Journals (Sweden)

    Rolando O Santos

    Full Text Available Recreational fisheries can be prone to severe declines, yet these fisheries, particularly catch-and-release, are often data-limited, constraining our ability to conduct stock assessments. A combination of catch and effort indices derived from fisheries-dependent data (FDD gathered from fishing logbooks could be a powerful approach to inform these data gaps. This study demonstrates the utility of using different catch metrics such as indices of abundance, species richness associated with reported catch, and the success rate of targeted trips, to assess historical shifts in the trajectory of the data-limited bonefish (Albula vulpes fishery in Florida Bay, an economically-important recreational fishery within the Caribbean Basin. We used FDD from fishing guide reports submitted to Everglades National Park to determine temporal patterns in the bonefish population over the past 35 years. These reports indicated a decline in recreational catches in Florida Bay since the late 1980s, with an accelerated decline starting in the late 1990s-early 2000s. Analyses showed an overall 42% reduction in bonefish catches. Trends in the proportion of positive trips (i.e., the probability of catching success followed the declining catch patterns, suggesting major population changes starting in 1999-2000. As bonefish catches declined, species richness in bonefish trips increased by 34%, suggesting a decrease in bonefish abundance and/or shift in fishing effort (e.g., giving-up time, changes in preferred species. Results provide additional resolution to a pattern of decline for bonefish in South Florida and highlight the value of reconstructing time-series for the development of hypotheses about the potential driving mechanisms of species decline. Further, the data-limited nature of most recreational fisheries, and the increase in a use of catch-and-release as a fisheries management strategy point to the need to develop further data integration tools to assess

  14. Do limiting factors at Alaskan treelines shift with climatic regimes?

    International Nuclear Information System (INIS)

    Ohse, B; Jansen, F; Wilmking, M

    2012-01-01

    Trees at Alaskan treelines are assumed to be limited by temperature and to expand upslope and/or to higher latitudes with global warming. However, recent studies describe negative temperature responses and drought stress of Alaskan treeline trees in recent decades. In this study, we have analyzed the responses of treeline white spruce to temperature and precipitation according to different climatic regimes in Alaska, described as negative (cool) and positive (warm) phases of the Pacific Decadal Oscillation (PDO). We found that in three consecutive phases (positive from 1925–46, negative from 1947–76, and positive again from 1977–98), the growth responses to temperature and precipitation differed markedly. Before 1947, in a phase of warm winters and with summer temperatures being close to the century mean, the trees at most sites responded positively to summer temperature, as one would expect from treeline trees at northern high latitudes. Between 1947 and 1976, a phase of cold winters and average summers, the trees showed similar responses, but a new pattern of negative responses to the summer temperature of the year prior to growth coupled with positive responses to the precipitation in the same year emerged at some sites. As the precipitation was relatively low at those sites, we assume that drought stress might have played a role. However, the climate responses were not uniform but were modified by regional gradients (trees at northern sites responded more often to temperature than trees at southern sites) and local site conditions (forest trees responded more often to precipitation than treeline trees), possibly reflecting differences in energy and water balance across regions and sites, respectively. However, since the shift in the PDO in 1976 from a negative to a positive phase, the trees’ climate–growth responses are much less pronounced and climate seems to have lost its importance as a limiting factor for the growth of treeline white spruce. If

  15. Cardiovascular oxygen transport limitations to thermal niche expansion and the role of environmental Po2 in Antarctic notothenioid fishes.

    Science.gov (United States)

    Buckley, Bradley A; Hedrick, Michael S; Hillman, Stanley S

    2014-01-01

    The notothenioid fishes of the Southern Ocean possess some of the lowest upper thermal thresholds of any species and display a range of cardiovascular features that distinguish them from other fishes. Some species lack hemoglobin, and it has been posited that the inability to deliver sufficient oxygen at elevated temperature may in part determine upper thermal thresholds. Here, we provide an analysis of systemic O2 transport based on circulatory resistance, cardiac outputs, and cardiac power for three species of Antarctic fishes, including species that possess hemoglobin (Trematomus bernacchii, Pagothenia borchgrevinki) and a species lacking hemoglobin (Chaenocephalus aceratus) and that differ in their cardiovascular characteristics. This analysis supports the hypothesis that the mutation resulting in the lack of hemoglobin would be metabolically prohibitive at elevated temperatures. The analysis also suggests that such a mutation would be least detrimental to species with greater cardiac power outputs and lower total peripheral resistance. Decreased environmental Po2 has the greatest detrimental effect on the metabolic capacity in the species without hemoglobin. These data indicate that differences in cardiovascular characteristics of the notothenioid fishes place varying limits on thermal niche expansion in these species, but any significant increase in environmental temperature or decrease in environmental Po2 will prohibit maintenance of cardiovascular systemic O2 transport in all species. These data also suggest an evolutionary sequence of events such that a reduction in hematocrit, to reduce blood viscosity and resistance, was a first step in the invasion of low-temperature habitats and loss of hemoglobin was followed by increased cardiac power output to achieve sustainable metabolic rates.

  16. Limiting factors in single particle cryo electron tomography

    Directory of Open Access Journals (Sweden)

    Mikhail Kudryashev

    2012-07-01

    Full Text Available Modern methods of cryo electron microscopy and tomography allow visualization of protein nanomachines in their native state at the nanometer scale. Image processing methods including sub-volume averaging applied to repeating macromolecular elements within tomograms allow exploring their structures within the native context of the cell, avoiding the need for protein isolation and purification. Today, many different data acquisition protocols and software solutions are available to researchers to determine average structures of macromolecular complexes and potentially to classify structural intermediates. Here, we list the density maps reported in the literature, and analyze each structure for the chosen instrumental settings, sample conditions, main processing steps, and obtained resolution. We present conclusions that identify factors currently limiting the resolution gained by this approach.

  17. Variability in connectivity patterns of fish with ontogenetic migrations: Modelling effects of abiotic and biotic factors

    Directory of Open Access Journals (Sweden)

    Susanne Eva Tanner

    2015-10-01

    Full Text Available Connectivity is a critical property of marine fish populations as it drives population replenishment, determines colonization patterns and the resilience of populations to harvest. Understanding connectivity patterns is particularly important in species that present ontogenetic migrations and segregated habitat use during their life history, such as marine species with estuarine nursery areas. Albeit challenging, fish movement can be estimated and quantified using different methodologies depending on the life history stages of interest (e.g. biophysical modelling, otolith chemistry, genetic markers. Relative contributions from estuarine nursery areas to the adult coastal populations were determined using otolith elemental composition and maximum likelihood estimation for four commercially important species (Dicentrarchus labrax, Plathichtys flesus, Solea senegalensis and Solea solea and showed high interannual variability. Here, the effects of abiotic and biotic factors on the observed variability in connectivity rates and extent between estuarine juvenile and coastal adult subpopulations are investigated using generalized linear models (GLM and generalized mixed models (GMM. Abiotic factors impacting both larval and juvenile life history stages are included in the models (e.g. wind force and direction, NAO, water temperature while biotic factors relative to the estuarine residency of juvenile fish are evaluated (e.g. juvenile density, food availability. Factors contributing most to the observed variability in connectivity rates are singled out and compared among species. General trends are identified and results area discussed in the general context of identifying potential management frameworks applicable to different life stages and which may prove useful for ontogenetically migrating species.

  18. Factors associated with worker slipping in limited-service restaurants.

    Science.gov (United States)

    Courtney, Theodore K; Verma, Santosh K; Huang, Yueng-Hsiang; Chang, Wen-Ruey; Li, Kai Way; Filiaggi, Alfred J

    2010-02-01

    Slips, trips and falls (STF) are responsible for a substantial injury burden in the global workplace. Restaurant environments are challenged by STF. This study assessed individual and work environment factors related to slipping in US limited-service restaurant workers. Workers in 10 limited-service restaurants in Massachusetts were recruited to participate. Workers' occupational slip and/or fall history within the past 4 weeks was collected by multilingual written questionnaires. Age, gender, job tenure, work hours per week and work shift were also collected. Shoe type, condition and gross shoe contamination were visually assessed. Floor friction was measured and each restaurant's overall mean coefficient of friction (COF) was calculated. The logistic generalised estimating equations model was used to compute adjusted odds ratios (OR). Of 125 workers, 42 reported one or more slips in the past 4 weeks with two reporting a resultant fall. Results from multivariable regression showed that higher restaurant mean COF was significantly associated with a decreased risk of self-reported slipping (OR 0.59, 95% CI 0.42 to 0.82). From the highest to the lowest COF restaurant, the odds of a positive slip history increased by a factor of more than seven. Younger age, male gender, lower weekly work hours and the presence of gross contamination on worker's shoe sole were also associated with increased odds of slip history. Published findings of an association between friction and slipping and falling in actual work environments are rare. The findings suggest that effective intervention strategies to reduce the risk of slips and falls in restaurant workers could include increasing COF and improving housekeeping practices.

  19. Fish allergy and fish allergens

    DEFF Research Database (Denmark)

    Kuehn, A; Hilger, Christiane; Ollert, Markus

    2016-01-01

    Fish is one of the main elicitors for food allergies. For a long time, the clinical picture of fish allergy was reduced to the following features. First, fish-allergic patients suffer from a high IgE cross-reactivity among fishes so that they have to avoid all species. Second, clinically relevant...... symptoms are linked to the presence of IgE-antibodies recognizing parvalbumin, the fish panallergen. This view was challenged by results from recent studies as follows. 1. Allergic reactions which are limited to single or several fish species (mono-or oligosensitisations) apply not only to single cases...... but patients with this phenotype constitute an important sub-group among fish-allergic individuals. 2. Newly identified fish allergens, enolases, aldolases, and fish gelatin, are of high relevance as the majority of the fish-allergic individuals seem to develop specific IgE against these proteins. The present...

  20. Limited Capacity for Faster Digestion in Larval Coral Reef Fish at an Elevated Temperature.

    Science.gov (United States)

    McLeod, Ian M; Clark, Timothy D

    2016-01-01

    The prevalence of extreme, short-term temperature spikes in coastal regions during summer months is predicted to increase with ongoing climate change. In tropical systems, these changes are predicted to increase the metabolic demand of coral reef fish larvae while also altering the plankton communities upon which the larvae feed during their pelagic phase. The consequences of these predictions remain speculative in the absence of empirical data on the interactive effects of warm temperatures on the metabolism, postprandial processes and growth responses of coral reef fish larvae. Here, we tested the effect of increased temperature on the metabolism, postprandial performance and fine-scale growth patterns of a coral reef fish (Amphiprion percula) in the latter half of its ~11-d larval phase. First, we measured the length and weight of fed versus fasted larvae (N = 340; mean body mass 4.1±0.05 mg) across fine temporal scales at a typical current summer temperature (28.5°C) and a temperature that is likely be encountered during warm summer periods later this century (31.5°C). Second, we measured routine metabolic rate (Mo2 routine) and the energetics of the postprandial processes (i.e., digestion, absorption and assimilation of a meal; termed specific dynamic action (SDA)) at both temperatures. Larvae fed voraciously when provided with food for a 12-hour period and displayed a temperature-independent increase in mass of 40.1% (28.5°C) and 42.6% (31.5°C), which was largely associated with the mass of prey in the gut. A subsequent 12-h fasting period revealed that the larvae had grown 21.2±4.8% (28.5°C) and 22.8±8.8% (31.5°C) in mass and 10.3±2.0% (28.5°C) and 7.8±2.6% (31.5°C) in length compared with pre-feeding values (no significant temperature effect). Mo2 routine was 55±16% higher at 31.5°C and peak Mo2 during the postprandial period was 28±11% higher at 31.5°C, yet elevated temperature had no significant effect on SDA (0.51±0.06 J at 28.5°C vs

  1. Limited Capacity for Faster Digestion in Larval Coral Reef Fish at an Elevated Temperature.

    Directory of Open Access Journals (Sweden)

    Ian M McLeod

    Full Text Available The prevalence of extreme, short-term temperature spikes in coastal regions during summer months is predicted to increase with ongoing climate change. In tropical systems, these changes are predicted to increase the metabolic demand of coral reef fish larvae while also altering the plankton communities upon which the larvae feed during their pelagic phase. The consequences of these predictions remain speculative in the absence of empirical data on the interactive effects of warm temperatures on the metabolism, postprandial processes and growth responses of coral reef fish larvae. Here, we tested the effect of increased temperature on the metabolism, postprandial performance and fine-scale growth patterns of a coral reef fish (Amphiprion percula in the latter half of its ~11-d larval phase. First, we measured the length and weight of fed versus fasted larvae (N = 340; mean body mass 4.1±0.05 mg across fine temporal scales at a typical current summer temperature (28.5°C and a temperature that is likely be encountered during warm summer periods later this century (31.5°C. Second, we measured routine metabolic rate (Mo2 routine and the energetics of the postprandial processes (i.e., digestion, absorption and assimilation of a meal; termed specific dynamic action (SDA at both temperatures. Larvae fed voraciously when provided with food for a 12-hour period and displayed a temperature-independent increase in mass of 40.1% (28.5°C and 42.6% (31.5°C, which was largely associated with the mass of prey in the gut. A subsequent 12-h fasting period revealed that the larvae had grown 21.2±4.8% (28.5°C and 22.8±8.8% (31.5°C in mass and 10.3±2.0% (28.5°C and 7.8±2.6% (31.5°C in length compared with pre-feeding values (no significant temperature effect. Mo2 routine was 55±16% higher at 31.5°C and peak Mo2 during the postprandial period was 28±11% higher at 31.5°C, yet elevated temperature had no significant effect on SDA (0.51±0.06 J at 28.5

  2. Hierarchy in factors affecting fish biodiversity in floodplain lakes of the Mississippi Alluvial Valley

    Science.gov (United States)

    Dembkowski, D.J.; Miranda, L.E.

    2012-01-01

    River-floodplain ecosystems offer some of the most diverse and dynamic environments in the world. Accordingly, floodplain habitats harbor diverse fish assemblages. Fish biodiversity in floodplain lakes may be influenced by multiple variables operating on disparate scales, and these variables may exhibit a hierarchical organization depending on whether one variable governs another. In this study, we examined the interaction between primary variables descriptive of floodplain lake large-scale features, suites of secondary variables descriptive of water quality and primary productivity, and a set of tertiary variables descriptive of fish biodiversity across a range of floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas (USA). Lakes varied considerably in their representation of primary, secondary, and tertiary variables. Multivariate direct gradient analyses indicated that lake maximum depth and the percentage of agricultural land surrounding a lake were the most important factors controlling variation in suites of secondary and tertiary variables, followed to a lesser extent by lake surface area. Fish biodiversity was generally greatest in large, deep lakes with lower proportions of watershed agricultural land. Our results may help foster a holistic approach to floodplain lake management and suggest the framework for a feedback model wherein primary variables can be manipulated for conservation and restoration purposes and secondary and tertiary variables can be used to monitor the success of such efforts. ?? 2011 Springer Science+Business Media B.V.

  3. Factors affecting fish biodiversity in floodplain lakes of the Mississippi Alluvial Valley

    Science.gov (United States)

    Miranda, Leandro E.; Dembkowski, Daniel J.

    2012-01-01

    River-floodplain ecosystems offer some of the most diverse and dynamic environments in the world. Accordingly, floodplain habitats harbor diverse fish assemblages. Fish biodiversity in floodplain lakes may be influenced by multiple variables operating on disparate scales, and these variables may exhibit a hierarchical organization depending on whether one variable governs another. In this study, we examined the interaction between primary variables descriptive of floodplain lake large-scale features, suites of secondary variables descriptive of water quality and primary productivity, and a set of tertiary variables descriptive of fish biodiversity across a range of floodplain lakes in the Mississippi Alluvial Valley of Mississippi and Arkansas (USA). Lakes varied considerably in their representation of primary, secondary, and tertiary variables. Multivariate direct gradient analyses indicated that lake maximum depth and the percentage of agricultural land surrounding a lake were the most important factors controlling variation in suites of secondary and tertiary variables, followed to a lesser extent by lake surface area. Fish biodiversity was generally greatest in large, deep lakes with lower proportions of watershed agricultural land. Our results may help foster a holistic approach to floodplain lake management and suggest the framework for a feedback model wherein primary variables can be manipulated for conservation and restoration purposes and secondary and tertiary variables can be used to monitor the success of such efforts.

  4. Economic and Environmental Impacts of Improving Growth Rate and Feed Efficiency in Fish Farming Depend on Nitrogen and Density Limitation

    NARCIS (Netherlands)

    Besson, M.; Komen, H.; Vandeputte, M.; Aubin, J.; Boer, de I.J.M.; Arendonk, van J.A.M.

    2014-01-01

    The aim of fish breeding is to increase profit by producing faster growing fish with lower feed intake. However, little is known about the economic and environmental impacts of selective breeding programs for fish. We modelled a fish farm producing African catfish in a Recirculating Aquaculture

  5. Factors limiting the recovery of boreal toads (Bufo b. boreas)

    Science.gov (United States)

    Carey, C.; Corn, P.S.; Jones, M.S.; Livo, L.J.; Muths, E.; Loeffler, C.W.; Lannoo, M.

    2005-01-01

    Boreal toads (Bufo b. boreas) are widely distributed over much of the mountainous western United States. Populations in the Southern Rocky Mountains suffered extensive declines in the late 1970s through early 1980s (Carey, 1993). At the time, these mass mortalities were thought to be associated with a bacterial infection (Carey, 1993). Although the few populations that survived the mass die-offs were not systematically monitored until at least 1993, no mass mortalities had been observed until 1996 when die-offs were observed. A mycotic skin infection associated with a chytrid fungus is now causing mortality of toads in at least two of the populations (M.S. Jones and D.E. Green, unpublished data; Muths et al., 2003). Boreal toads are now absent throughout large areas of their former distribution in Colorado and southern Wyoming and may be extinct in New Mexico (Corn et al., 1989; Carey, 1993; Stuart and Painter, 1994). These toads are classified as “endangered” by Colorado and New Mexico and are designated as a protected non-game species in Wyoming. The U.S. Fish and Wildlife Service has categorized the Southern Rocky Mountain populations for federal listing and is currently reviewing their designation as a “warranted but precluded” species for possible listing in the next few years. For the management of boreal toads and their habitats, a Boreal Toad Recovery Team was formed by the Colorado Division of Wildlife in 1995 as part of a collaborative effort with federal agencies within the United States’ departments of the Interior and Agriculture and with agencies in two adjoining states. To date, conservation agreements have been signed by eight state and federal agencies and by the Colorado Natural Heritage Program. Although boreal toads were considered common throughout their range in Colorado, no comprehensive surveys of the numbers and sizes of their populations were conducted prior to mass die-offs in the 1970s. Surveys completed in the late 1980s to

  6. Coded-Wire Tag Expansion Factors for Chinook Salmon Carcass Surveys in California: Estimating the Numbers and Proportions of Hatchery-Origin Fish

    Directory of Open Access Journals (Sweden)

    Michael S. Mohr

    2013-12-01

    Full Text Available Recovery of fish with adipose fin clips (adc and coded-wire tags (cwt in escapement surveys allows calculation of expansion factors used in estimation of the total number of fish from each adc,cwt release group, allowing escapement to be resolved by age and stock of origin. Expanded recoveries are used to derive important estimates such as the total number and proportion of hatchery-origin fish present. The standard estimation scheme assumes accurate visual classification of adc status, which can be problematic for decomposing carcasses. Failure to account for this potential misclassification can lead to significant estimation bias. We reviewed sample expansion factors used for the California Central Valley Chinook salmon 2010 carcass surveys in this context. For upper Sacramento River fall-run and late fall-run carcass surveys, the estimated proportions of adc,cwt fish for fresh and non-fresh carcasses differed substantially, likely from the under-recognition of adc fish in non-fresh carcasses. The resulting estimated proportions of hatchery-origin fish in the upper Sacramento River fall-run and late fall-run carcass surveys were 2.33 to 2.89 times higher if only fresh carcasses are considered. Similar biases can be avoided by consideration of only fresh carcasses for which determination of adc status is relatively straightforward; however, restricting the analysis entirely to fresh carcasses may limit precision because of reduced sample size, and is only possible if protocols for sampling and recording data ensure that the sample data and results for fresh carcasses can be extracted. Thus we recommend sampling protocols that are clearly documented and separately track fresh versus non-fresh carcasses, either collecting only definitively adc fish or that carefully track non-fresh carcasses that are definitively adc versus those that are possibly adc. This would allow judicious use of non-fresh carcass data when sample sizes are otherwise

  7. Is iron a limiting factor of Nodularia spumigena blooms?

    Directory of Open Access Journals (Sweden)

    Lidia Paczuska

    2003-12-01

    Full Text Available It is well known that a deficiency of iron, a trace element essential to every living organism, limits the growth of algae and cyanobacteria. Nodularia spumigena Mertens is a blue-green algae species inhabiting the Baltic region that often forms toxic blooms.     The aim of the study was to assess the growth of the toxic cyanobacteria with respect to iron bioavailability. The measured growth parameters were the numbers of cells (optical density, chlorophyll a and pheopigment a concentrations. The iron concentrations used ranged from 10-7 to 10-4 mol dm-3. Under iron stress conditions (<5 × 10-7 mol dm-3, growth inhibition, gradual pigment decay and cell mortality were observed. However, enriching the medium with complexing factors like citric acid and EDTA significantly stimulated the growth rate and chlorophyll a production. The citric acid - EDTA - Fe (5 × 10-7 mol dm-3 complex was demonstrably effective in stimulating the rate of cell division. Starting with 10-6 mol dm-3, the higher the iron(III concentration used in the media, the more intensive the growth of the cyanobacteria populations. This was most rapid in the presence of high iron concentrations (10-4 mol dm-3, regardless of the presence of complexing agents.     It appears that the growth of toxic cyanobacteria N. spumigena, and thus also its ability to form blooms, may well depend on iron availability in the environment.

  8. Factors which could limit the nuclear fuel cycle development

    International Nuclear Information System (INIS)

    Pecqueur, M.; Barre, B.

    1977-01-01

    The nuclear fuel cycle is a most important industry for the energy future of the world. It has also a leading part as regards the physical continuity of energy supply of the countries engaged in the nuclear field. The development of this industry is subject to the economic or political constraints involved by the availability of raw materials, technologies or production means. The various limiting factors which could affect the different stages of the fuel cycle are linked with the technical, economic and financial aspects, with the impact on the environment, nuclear safety, risks of non-pacific uses and proliferation of arms. Interesting to note is also the correlation between the fuel cycle development and the problems of energy independence and security of nuclear programs. As a conclusion, the nuclear fuel cycle industry is confronted to difficulties due to its extremely rapid growth (doubling time 5 years) which only few heavy industries have encountered for long periods. It is more over submitted to the political and safety constraints always linked with nuclear matters. The task is therefore a difficult one. But the objective is worth-while since it is a condition to the development of nuclear industry [fr

  9. Oxygen delivery to the fish eye: root effect as crucial factor for elevated retinal PO2.

    Science.gov (United States)

    Waser, W; Heisler, N

    2005-11-01

    Although the retina has one of the highest metabolic rates among tissues, certain teleost fishes lack any vascular supply to this organ which, in combination with the overall thickness of the organ, results in extremely long diffusion distances. As the only way to compensate for these obstacles, oxygen partial pressure (PO2) in the eyes of such fish is elevated far above atmospheric values. Although not supported by any direct evidence, the enhancement of PO2 is considered to be related to the Root effect, the release upon acidification of Hb-bound O2 into physical dissolution, possibly supported by counter-current multiplication similar to the loop of Henle. The present study evaluates the magnitude of intraocular PO2 enhancement under tightly controlled physiological conditions, to directly confirm the involvement of the Root effect on intraocular PO2 in the retina of rainbow trout Oncorhynchus mykiss. Intraocular PO2 was determined with special polarographic microelectrodes inserted into the eye. PO2 profiles established in vivo by driving electrodes through the entire retina yielded average PO2 values between 10 mmHg (1.3 kPa) at the inner retinal surface and 382 mmHg (50.9 kPa) close to the outer retinal limit (Bruch's membrane). According to estimates on the basis of the diffusion distances determined from sections of the retina (approximately 436 microm at the site of PO2 measurement) and literature data on specific oxygen consumption, the in vivo determined values would be sufficient to cover the oxygen demand of the retina with some safety margin. For a clear and direct in-tissue-test as to the involvement of the Root effect, an isolated in vitro eye preparation was established in order to avoid the problem of indirect blood supply to the eye from the dorsal aorta only via the pseudobranch, a hemibranch thought to modulate blood composition before entry of the eye. Any humoral effects (e.g. catecholamines) were eliminated by perfusing isolated eyes

  10. Mercury Contamination in Fish in Midcontinent Great Rivers of the United States: Importance of Species Traits and Environmental Factors

    Science.gov (United States)

    We measured mercury (Hg) concentrations in whole fish from the Upper Mississippi, Missouri, and Ohio Rivers to characterize the extent and magnitude of Hg contamination and to identify environmental factors influencing Hg accumulation. Concentrations were generally lower (80% of ...

  11. Evidence of bottom-up limitations in nearshore marine systems based on otolith proxies of fish growth

    Science.gov (United States)

    von Biela, Vanessa R.; Kruse, Gordon H.; Mueter, Franz J.; Black, Bryan A.; Douglas, David C.; Helser, Thomas E.; Zimmerman, Christian E.

    2015-01-01

    Fish otolith growth increments were used as indices of annual production at nine nearshore sites within the Alaska Coastal Current (downwelling region) and California Current (upwelling region) systems (~36–60°N). Black rockfish (Sebastes melanops) and kelp greenling (Hexagrammos decagrammus) were identified as useful indicators in pelagic and benthic nearshore food webs, respectively. To examine the support for bottom-up limitations, common oceanographic indices of production [sea surface temperature (SST), upwelling, and chlorophyll-a concentration] during summer (April–September) were compared to spatial and temporal differences in fish growth using linear mixed models. The relationship between pelagic black rockfish growth and SST was positive in the cooler Alaska Coastal Current and negative in the warmer California Current. These contrasting growth responses to SST among current systems are consistent with the optimal stability window hypothesis in which pelagic production is maximized at intermediate levels of water column stability. Increased growth rates of black rockfish were associated with higher chlorophyll concentrations in the California Current only, but black rockfish growth was unrelated to the upwelling index in either current system. Benthic kelp greenling growth rates were positively associated with warmer temperatures and relaxation of downwelling (upwelling index near zero) in the Alaska Coastal Current, while none of the oceanographic indices were related to their growth in the California Current. Overall, our results are consistent with bottom-up forcing of nearshore marine ecosystems—light and nutrients constrain primary production in pelagic food webs, and temperature constrains benthic food webs.

  12. Resolution-limiting factors in 2-deoxyglucose autoradiography. I. Factors other than diffusion

    Energy Technology Data Exchange (ETDEWEB)

    Gallistel, C.R.; Nichols, S. (Pennsylvania Univ., Philadelphia, PA (USA). Dept. of Psychology)

    1983-05-16

    The authors measured the extent to which factors other than the diffusion of the radioactive label during tissue preparation limits the spatial resolving power of 2-deoxyglucose (2-DG) autoradiography. Radioactive swept frequency gratings were created using microcircuit lithography. The gratings consisted of alternating equal width radioactive and non-radioactive bars in groups of narrowing bar width (effective range 500-20 ..mu..m). The vertical thickness of the gratings ranged from 2.25 to 20 ..mu..m. The isotope in the radioactive bars was either /sup 14/C or /sup 3/H. A variety of X-ray films were exposed to these gratings and the resulting images scanned with microdensitometers or video digitizers to determine the fall off in image contrast (dark-bar values minus light-bar values) as a function of the number of dark bars (lines) per millimeter. The power of the isotope was the resolution limiting factor. Grating thickness and type of film made little difference. The limit of resolution with /sup 14/C was 10 lines/mm: with /sup 3/H it was 25 lines/mm. The microdensitometer itself is apt to be a resolution limiting factor; the resolving power of those commonly used in autoradiography is unlikely to exceed 10 lines/mm. From measurements of the steepness of gray-matter to white-matter transitions in the image from a tissue section, they conclude that the resolution in the image was no worse than 1.6-3.2 lines/mm. Either the isotope or diffusion of the 2-DG during tissue preparation must be the factor that limits resolution.

  13. Importance of fish behaviour in modelling conservation problems: food limitation as an example

    Science.gov (United States)

    Steven Railsback; Bret Harvey

    2011-01-01

    Simulation experiments using the inSTREAM individual-based brown trout Salmo trutta population model explored the role of individual adaptive behaviour in food limitation, as an example of how behaviour can affect managers’ understanding of conservation problems. The model includes many natural complexities in habitat (spatial and temporal variation in characteristics...

  14. 76 FR 59658 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2011-09-27

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets..., the antidumping duty order on certain frozen fish fillets from the Socialist Republic of Vietnam... of initiation for the new shipper review of [[Page 59659

  15. Influence of seasonal, diel, lunar, and other environmental factors on upstream fish passage in the igarapava fish ladder, Brazil

    Science.gov (United States)

    Bizzotto, P.M.; Godinho, Alexandre L.; Vono, V.; Kynard, B.; Godinho, Hugo P.

    2009-01-01

    Upstream fish passage was evaluated during 12 months in the vertical-slot Igarapava Fish Ladder constructed around Igarapava Dam, in the heavily dammed Grande River, Southeast Brazil. A video monitoring system was used to observe 61,621 fish that passed the ladder, of which 93.5% were identified to 15 taxa. Among the migratory species, the most abundant were Pimelodus maculatus (33.6% of all fish), Leporinus octofasciatus (31.4%), Leporinus friderici (4.5%), and Prochilodus lineatus (3.1%). Seven taxa were classified as nonmigratory, and of these taxa, the small Bryconamericus stramineus was the most abundant (12.7%) of all fishes. Passage of the 'nonmigratory' taxa upstream in the ladder shows they are migratory in this system and have a strong behavioural drive to move to upstream habitat. Passage of most taxa had a strong seasonal pattern. While some species passed primarily during the day, others showed a distinct nocturnal pattern. Lunar phase and water temperature also strongly affected passage of some taxa. Rainfall and dam discharge had a small or null influence on most taxa; perhaps due to the fairly small catchment area of the reservoir and the highly regulated discharge at Igarapava Dam. ?? 2009 John Wiley & Sons A/S.

  16. Effect of dietary fish oil and corn oil on blood biochemical factors in diabetic Rat

    Directory of Open Access Journals (Sweden)

    Mehdi Shariati

    2005-09-01

    Full Text Available Background: The potential role of omega – 3 (ω-3 and omega-6 (ω-6 fatty acids on blood biochemical factors are in interest and controversy. Some experiences showed that omega – 3 (ω-3 and omega-6 (ω-6 fatty acids have a potential effect on triglyceride, LDL-cholesterol, HDL-cholesterol and total cholesterol levels in diabetes mellitus. Methods: Male rats were divided into four groups (one normal group and three diabetic groups. Induction of diabetes was done by streptozotocin [50mg/kg, s.c. (STZ]. In diabetic groups, one group was Control, received STZ alone, and the other diabetic groups were fed with fish oil or corn oil for 8 weeks after 4 weeks of induction of diabetes. Plasma glucose, total cholesterol, triglyceride, LDL- choleserol and HDL-cholesterol were measured at 4 and 8 weeks after intervention. Results: Fish oil and corn oil diets had an inhibitory effect on increased plasma glucose in diabetic rat by 46.8% and 40.7%, respectively. Diabetic rats in the control group demonstrated increased plasma total cholesterol, triglyceride and LDL-cholesterol levels, but plasma total cholesterol, triglyceride and LDL-cholesterol levels were significantly decreased and HDL-cholesterol level was increased by both diets in interventional groups. Conclusion: Corn oil and fish oil supplementation have a role on plasma glucose and lipid profile in diabetic rats. To understand the functional mechanisms of these diets, further studies remain to be accomplished.

  17. 76 FR 81913 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2011-12-29

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... antidumping duty order on certain frozen fish fillets from the Socialist Republic of Vietnam.\\1\\ Subsequent to..., 2012. \\1\\ See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Preliminary Results...

  18. 76 FR 12939 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2011-03-09

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... the Preliminary Results of the seventh new shipper reviews of certain frozen fish fillets from the... later than April 14, 2011. \\1\\ See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam...

  19. 75 FR 30374 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-06-01

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets.... See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Preliminary Results of New.... See Memorandum to the File, from Javier Barrientos, Senior Case Analyst, Certain Frozen Fish Fillets...

  20. 76 FR 20626 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2011-04-13

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... and requests for revocation in part for certain frozen fish fillets from the Socialist Republic of... administrative reviews and requests for revocation in part for certain frozen fish fillets from the Socialist...

  1. 75 FR 20983 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-04-22

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... frozen fish fillets from the Socialist Republic of Vietnam covering the period August 1, 2008, through...''), covering the period August 1, 2008, through July 31, 2009. See Certain Frozen Fish Fillets from the...

  2. 75 FR 80795 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-12-23

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... of the sixth administrative and new shipper reviews of certain frozen fish fillets from the Socialist... January 13, 2011. \\1\\ See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Notice of...

  3. 75 FR 44938 - Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-07-30

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... the period August 1, 2008, through July 31, 2009. See Certain Frozen Fish Fillets from the Socialist...: Antidumping Duty Administrative Review of Certain Frozen Fish Fillets from the Socialist Republic of Vietnam...

  4. 75 FR 26199 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-05-11

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... 31, 2009. See Certain Frozen Fish Fillets From the Socialist Republic of Vietnam: Preliminary Results... Barrientos, Senior Case Analyst, Certain Frozen Fish Fillets from the Socialist Republic of Vietnam, dated...

  5. 75 FR 47771 - Certain Frozen Fish Fillets from the Socialist Republic of Vietnam: Extension of Time Limit for...

    Science.gov (United States)

    2010-08-09

    ... DEPARTMENT OF COMMERCE International Trade Administration [A-552-801] Certain Frozen Fish Fillets... initiation of antidumping duty new shipper reviews for certain frozen fish fillets from the Socialist Republic of Vietnam covering the period August 1, 2009, through February 15, 2010. See Certain Frozen Fish...

  6. Importance of Natural and Anthropogenic Environmental Factors to Fish Communities of the Fox River in Illinois

    Science.gov (United States)

    Schnier, Spencer; Cai, Ximing; Cao, Yong

    2016-02-01

    The dominant environmental determinants of aquatic communities have been a persistent topic for many years. Interactions between natural and anthropogenic characteristics within the aquatic environment influence fish communities in complex ways that make the effect of a single characteristic difficult to ascertain. Researchers are faced with the question of how to deal with a large number of variables and complex interrelationships. This study utilized multiple approaches to identify key environmental variables to fish communities of the Fox River Basin in Illinois: Pearson and Spearman correlations, an algorithm based on information theory called mutual information, and a measure of variable importance built into the machine learning algorithm Random Forest. The results are based on a dataset developed for this study, which uses a fish index of biological integrity (IBI) and its ten component metrics as response variables and a range of environmental variables describing geomorphology, stream flow statistics, climate, and both reach-scale and watershed-scale land use as independent variables. Agricultural land use and the magnitude and duration of low flow events were ranked by the algorithms as key factors for the study area. Reach-scale characteristics were dominant for native sunfish, and stream flow metrics were rated highly for native suckers. Regression tree analyses of environmental variables on fish IBI identified breakpoints in percent agricultural land in the watershed (~64 %), duration of low flow pulses (~12 days), and 90-day minimum flow (~0.13 cms). The findings should be useful for building predictive models and design of more effective monitoring systems and restoration plans.

  7. Investigation of the factors influencing radiocesium concentrations of fish inhabiting natural aquatic ecosystems

    International Nuclear Information System (INIS)

    Jinks, S.M.

    1975-01-01

    Distributions of radioactive and stable cesium were determined in water, sediment, and biota from eight different aquatic ecosystems between 1971 and 1973. The ecosystems included four lakes, fresh and brackish water regions of the Hudson River estuary, and two coastal marine sites. In the Hudson River estuary, the distribution of radiocesium between suspended and dissolved phases in water was found to be a function of salinity. Mean rates of deposition of suspended radiocesium into bottom sediment are calculated from the temporal changes in concentrations of the media, and observed depth distributions in sediment are semi-quantitatively described. Desorption by salt water is identified as the major mechanism for transport of radiocesium from bottom sediment in the lower estuary, and half-times for removal by this mechanism are estimated to be 1.5 to 2.0 years. Suspended-dissolved distributions of radiocesium in water, and depth distributions in sediment are also presented for lake and marine systems. Accumulation of radiocesium by fish is examined in relation to radiocesium distributions in water, sediment, and other biota, and to the chemical characteristics of each ecosystem. Radiocesium dissolved in water was the primary source to the fish in all ecosystems. Sediment inventories of 137 Cs constituted a secondary source which provided as much as 50 percent of the radiocesium in benthic feeding fish in the Hudson River. Dietary intake of 137 Cs is shown to be inversely related to the potassium concentration in the ambient water, and results in an inverse proportionality between the concentration factor in fish and the potassium concentrations in the different freshwater and estuarine ecosystems

  8. Factors mediating co-occurrence of an economically valuable introduced fish and its native frog prey.

    Science.gov (United States)

    Hartman, Rosemary; Pope, Karen; Lawler, Sharon

    2014-06-01

    Habitat characteristics mediate predator-prey coexistence in many ecological systems but are seldom considered in species introductions. When economically important introduced predators are stocked despite known negative impacts on native species, understanding the role of refuges, landscape configurations, and community interactions can inform habitat management plans. We measured these factors in basins with introduced trout (Salmonidae) and the Cascades frog (Rana cascadae) to determine, which are responsible for observed patterns of co-occurrence of this economically important predator and its native prey. Large, vegetated shallows were strongly correlated to co-occurrence, and R. cascadae larvae occur in shallower water when fish are present, presumably to escape predation. The number of nearby breeding sites of R. cascadae was also correlated to co-occurrence, but only when the western toad (Anaxyrus boreas) was present. Because A. boreas larvae are unpalatable to fish and resemble R. cascadae, they may provide protection from trout via Batesian mimicry. Although rescue-effect dispersal from nearby populations may maintain co-occurrence, within-lake factors proved more important for predicting co-occurrence. Learning which factors allow co-occurrence between economically important introduced species and their native prey enables managers to make better-informed stocking decisions. © 2013 Society for Conservation Biology.

  9. Factors Limiting Vocational Agriculture Student Participation in Supervised Occupational Experience Programs in Nebraska.

    Science.gov (United States)

    Foster, Richard M.

    1986-01-01

    In this study, economic factors were consistently rated as important considerations in limited student participation in supervised farm practice in Nebraska high schools. It was indicated that administrative support was the least limiting factor for student participation. (CT)

  10. Zooplankton of an urban coastal lagoon: composition and association with environmental factors and summer fish kill

    Directory of Open Access Journals (Sweden)

    Leonardo C. e Souza

    2011-06-01

    Full Text Available Zooplankton may be regarded as a sensitive tool for monitoring environmental variations in coastal lagoons due to their ability to immediately react to changes in the water column trophic features and salinity levels. As a coastal lagoon with a broad history of anthropic influence, Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil is widely used for water sports and artisanal fishing. The present study aimed to expand the knowledge base about zooplankton in the Rodrigo de Freitas Lagoon by assessing the composition and time-spatial distribution of the major zooplankton groups. Samples were collected fortnightly from at four distinct sampling points August 2001 to July 2002. At each point, salinity, temperature, dissolved oxygen and water transparency were measured. During the study period, the lagoon behaved as an spatially homogeneous environment in what regards the abiotic variables. However, all these variables showed significant differences along the time, mainly related to seasonality (air temperature and rainy and dry periods. The zooplankton community showed low taxonomic richness, with the predominance of species commonly found in coastal lagoons, especially with mesohaline conditions, as well as those found in estuaries. An interesting fact was the rise in zooplankton abundance at all sampling points right after a fish kill event. Such increase was caused mainly by the Brachionus plicatilis O.F. Müller 1786 species. Thus, the zooplankton community was affected by physical and chemical factors, mainly by the dissolved oxygen decline event and variations in the influx of seawater into the lagoon. In addition, phytoplankton availability and fish predation pressure were suggested as important regulating factors of the zooplankton community.

  11. Human Health Risk from Metals in Fish from Saudi Arabia: Consumption Patterns for Some Species Exceed Allowable Limits

    KAUST Repository

    Burger, Joanna

    2014-10-06

    ABSTRACT: Fish are a healthful source of protein, but contaminants in some fish pose a risk. While there are multiple risk assessments from Europe and North America, there are far fewer for other parts of the world. We examined the risks from mercury, arsenic, lead, and other metals in fish consumed by people in Jeddah area, Saudi Arabia, using site-specific data on consumption patterns and metal levels in fish. The U.S. Environmental Protection Agency\\'s Hazard Quotient (HQ) and cumulative Hazard Index (HI) for non-cancer endpoints and Carcinogenic Index for cancer were used to determine the health risk based on fish consumption rates. Of the 13 fish species examined, HQ was greater than 1 (indicating elevated risk) in two species for arsenic, and seven species for methylmercury. The cumulative HI for all metals was above 1 for all but three species of fish at the mean consumption rates. Generally, fish species with HI above 1 for one sampling location, had HI above 1 for all sampling locations. The implications of these findings are discussed in the light of strategies for reducing risk from fish consumption while encouraging dietary intakes of fish with low mercury and arsenic levels.

  12. The Big Fish-Little Pond Effect on Affective Factors Based on PISA 2012 Mathematics Achievement

    Directory of Open Access Journals (Sweden)

    Dilara BAKAN KALAYCIOĞLU

    2017-03-01

    Full Text Available In this study, the 2012 PISA Turkey student questionnaire data is considered to determine the big fish-little pond effect. The mathematics self-efficacy, self-concept and anxiety affective factors are examined to explain the relation of each of them with the school type, gender, socioeconomic status, student’s mathematics achievement and school’s mathematics achievement covariates. A total number of 771 students from 88 high schools are in the sample. Factor analyses’ results support the construct validity of the Student Questionnaire’s mathematics self-efficacy, anxiety and self-concept items. Data set is analyzed with Multiple Indicator Multiple Cause Model and the patterns of association with covariates and affective factors were tested simultaneously. According to the results, Anatolian high school students have a higher mathematics self-efficacy and lower mathematics anxiety than do the general high school students. However, when the student mathematics achievement and school mathematics achievement variables were inserted to the model, school type was not associated with mathematics self-efficacy. Moreover, Anatolian high school student’s mathematics anxiety was higher than that of the general high school students. Student’s mathematics achievement was the most significant predictor of the mathematics self-efficacy, anxiety and self-concept factors. Finally, school’s mathematics achievement was a significant predictor of only mathematics self-concept. The identification of increase in school’s mathematics achievement yields a decrease in the student’s mathematics self-concept may be considered as the most important result of this study. These results provide evidence about the Anatolian high schools’ students experience big fish-little pond effect.

  13. THE INFLUENCE OF LIMITING FACTORS ON ELECTRIC MACHINES ELECTROMAGNETIC POWER

    Directory of Open Access Journals (Sweden)

    Mr. Konstantin K. Kim

    2016-06-01

    Full Text Available The increase of electromechanical transducers single capacity is one of the main ways of their efficiency upgrading. The article discusses the impact of the main electromagnetic and me-chanical factors on the power, transmitted through the air gap of DC electric machines.

  14. Activity limitations and factors influencing functional outcome of ...

    African Journals Online (AJOL)

    EB

    2013-09-03

    Sep 3, 2013 ... life and satisfaction with life1,22. A recent study conducted among community dwelling stroke survivors found functional ability and independence to be the strongest predictor of, and were responsible for the greatest variance on participation22. For determining the factors influencing outcome with the use ...

  15. Six Sigma: Problems, Limitations, Critical Success Factors and Future Prospects

    Directory of Open Access Journals (Sweden)

    Paulo Mazieiro Pohlmann

    2015-12-01

    Full Text Available Six Sigma is a business strategy based on objective decision making and problem solving in order to achieve, maintain and maximize business success through understanding and meeting the needs of customers. The visualization of this methodology as a powerful tool in reducing variability and improving quality led to the interest in performing this bibliographical study, whose purpose was to assess the critical success factors and future prospects of this managerial system. A survey was conducted in order to discover the main critical success factors of the implementation of the methodology in organizations, among which stood out the proper selection of projects, connecting the project with the business strategy, customer focus, financial, human and infrastructure resources, the involvement of senior management, professional training, and cultural change.

  16. Factors Limiting Complete Tumor Ablation by Radiofrequency Ablation

    International Nuclear Information System (INIS)

    Paulet, Erwan; Aube, Christophe; Pessaux, Patrick; Lebigot, Jerome; Lhermitte, Emilie; Oberti, Frederic; Ponthieux, Anne; Cales, Paul; Ridereau-Zins, Catherine; Pereira, Philippe L.

    2008-01-01

    The purpose of this study was to determine radiological or physical factors to predict the risk of residual mass or local recurrence of primary and secondary hepatic tumors treated by radiofrequency ablation (RFA). Eighty-two patients, with 146 lesions (80 hepatocellular carcinomas, 66 metastases), were treated by RFA. Morphological parameters of the lesions included size, location, number, ultrasound echogenicity, computed tomography density, and magnetic resonance signal intensity were obtained before and after treatment. Parameters of the generator were recorded during radiofrequency application. The recurrence-free group was statistically compared to the recurrence and residual mass groups on all these parameters. Twenty residual masses were detected. Twenty-nine lesions recurred after a mean follow-up of 18 months. Size was a predictive parameter. Patients' sex and age and the echogenicity and density of lesions were significantly different for the recurrence and residual mass groups compared to the recurrence-free group (p < 0.05). The presence of an enhanced ring on the magnetic resonance control was more frequent in the recurrence and residual mass groups. In the group of patients with residual lesions, analysis of physical parameters showed a significant increase (p < 0.05) in the time necessary for the temperature to rise. In conclusion, this study confirms risk factors of recurrence such as the size of the tumor and emphasizes other factors such as a posttreatment enhanced ring and an increase in the time necessary for the rise in temperature. These factors should be taken into consideration when performing RFA and during follow-up

  17. Latent Factors Limiting the Performance of sEMG-Interfaces

    Directory of Open Access Journals (Sweden)

    Sergey Lobov

    2018-04-01

    Full Text Available Recent advances in recording and real-time analysis of surface electromyographic signals (sEMG have fostered the use of sEMG human–machine interfaces for controlling personal computers, prostheses of upper limbs, and exoskeletons among others. Despite a relatively high mean performance, sEMG-interfaces still exhibit strong variance in the fidelity of gesture recognition among different users. Here, we systematically study the latent factors determining the performance of sEMG-interfaces in synthetic tests and in an arcade game. We show that the degree of muscle cooperation and the amount of the body fatty tissue are the decisive factors in synthetic tests. Our data suggest that these factors can only be adjusted by long-term training, which promotes fine-tuning of low-level neural circuits driving the muscles. Short-term training has no effect on synthetic tests, but significantly increases the game scoring. This implies that it works at a higher decision-making level, not relevant for synthetic gestures. We propose a procedure that enables quantification of the gestures’ fidelity in a dynamic gaming environment. For each individual subject, the approach allows identifying “problematic” gestures that decrease gaming performance. This information can be used for optimizing the training strategy and for adapting the signal processing algorithms to individual users, which could be a way for a qualitative leap in the development of future sEMG-interfaces.

  18. Human Health Risk from Metals in Fish from Saudi Arabia: Consumption Patterns for Some Species Exceed Allowable Limits

    KAUST Repository

    Burger, Joanna; Gochfeld, Michael; Mannalamkunnath Alikunhi, Nabeel; Al-Jahdali, Haitham; Al-Jebreen, Dalal Hamad; Al-Suwailem, Abdulaziz M.; Aziz, Mohammed A M; Batang, Zenon B.

    2014-01-01

    ABSTRACT: Fish are a healthful source of protein, but contaminants in some fish pose a risk. While there are multiple risk assessments from Europe and North America, there are far fewer for other parts of the world. We examined the risks from

  19. Limited contemporary gene flow and high self-replenishment drives peripheral isolation in an endemic coral reef fish.

    Science.gov (United States)

    van der Meer, Martin H; Horne, John B; Gardner, Michael G; Hobbs, Jean-Paul A; Pratchett, Morgan; van Herwerden, Lynne

    2013-06-01

    Extensive ongoing degradation of coral reef habitats worldwide has lead to declines in abundance of coral reef fishes and local extinction of some species. Those most vulnerable are ecological specialists and endemic species. Determining connectivity between locations is vital to understanding recovery and long-term persistence of these species following local extinction. This study explored population connectivity in the ecologically-specialized endemic three-striped butterflyfish (Chaetodon tricinctus) using mt and msatDNA (nuclear microsatellites) to distinguish evolutionary versus contemporary gene flow, estimate self-replenishment and measure genetic diversity among locations at the remote Australian offshore coral reefs of Middleton Reef (MR), Elizabeth Reef (ER), Lord Howe Island (LHI), and Norfolk Island (NI). Mt and msatDNA suggested genetic differentiation of the most peripheral location (NI) from the remaining three locations (MR, ER, LHI). Despite high levels of mtDNA gene flow, there is limited msatDNA gene flow with evidence of high levels of self-replenishment (≥76%) at all four locations. Taken together, this suggests prolonged population recovery times following population declines. The peripheral population (NI) is most vulnerable to local extinction due to its relative isolation, extreme levels of self-replenishment (95%), and low contemporary abundance.

  20. Explanatory factors of female entrepreneurship and limiting elements

    Directory of Open Access Journals (Sweden)

    Carmina Pérez-Pérez

    2016-06-01

    Full Text Available Researches on entrepreneurship from a gender perspective reveal significant differences not only between the levels of participation of men and women in business, but also between the orientations, motives and business opportunities for both. Based on this fact, the following investigation is performed, whose objective is twofold: firstly, to know what are the aspects that influence the entrepreneurship of women and secondly, to identify what factors determine and/or difficult the creation and development of business that they undertake. To achieve both, it is reviewed, first, the literature on this subject and, second, are exposed the main results of the qualitative analysis with Atlas.ti from interviews with a group of Spanish entrepreneurs.

  1. Association of health involvement and attitudes towards eating fish on farmed and wild fish consumption in Belgium, Norway and Spain

    NARCIS (Netherlands)

    Altintzoglou, T.; Vanhonacker, F.; Verbeke, W.; Luten, J.B.

    2011-01-01

    Consumers in many European countries do not equally meet the recommended daily intake levels for fish consumption. Various factors that can influence fish consumption behaviour have been identified but limited research has been performed on fish consumption behaviour, discriminating between farmed

  2. The influence of chemical degradation during dietary exposures to fish on biomagnification factors and bioaccumulation factors.

    Science.gov (United States)

    Arnot, Jon A; Mackay, Donald

    2018-01-24

    The chemical dietary absorption efficiency (E D ) quantifies the amount of chemical absorbed by an organism relative to the amount of chemical an organism is exposed to following ingestion. In particular, E D can influence the extent of bioaccumulation and biomagnification for hydrophobic chemicals. A new E D model is developed to quantify chemical process rates in the gastrointestinal tract (GIT). The new model is calibrated with critically evaluated measured E D values (n = 250) for 80 hydrophobic persistent chemicals. The new E D model is subsequently used to estimate chemical reaction rate constants (k R ) assumed to occur in the lumen of the GIT from experimental dietary exposure tests (n = 255) for 165 chemicals. The new k R estimates are corroborated with k R estimates for the same chemicals from the same data derived previously by other methods. The roles of k R and the biotransformation rate constant (k B ) on biomagnification factors (BMFs) determined under laboratory test conditions and on BMFs and bioaccumulation factors (BAFs) in the environment are examined with the new model. In this regard, differences in lab and field BMFs are highlighted. Recommendations to address uncertainty in E D and k R data are provided.

  3. Efficiency limit factor analysis for the Francis-99 hydraulic turbine

    Science.gov (United States)

    Zeng, Y.; Zhang, L. X.; Guo, J. P.; Guo, Y. K.; Pan, Q. L.; Qian, J.

    2017-01-01

    The energy loss in hydraulic turbine is the most direct factor that affects the efficiency of the hydraulic turbine. Based on the analysis theory of inner energy loss of hydraulic turbine, combining the measurement data of the Francis-99, this paper calculates characteristic parameters of inner energy loss of the hydraulic turbine, and establishes the calculation model of the hydraulic turbine power. Taken the start-up test conditions given by Francis-99 as case, characteristics of the inner energy of the hydraulic turbine in transient and transformation law are researched. Further, analyzing mechanical friction in hydraulic turbine, we think that main ingredients of mechanical friction loss is the rotation friction loss between rotating runner and water body, and defined as the inner mechanical friction loss. The calculation method of the inner mechanical friction loss is given roughly. Our purpose is that explore and research the method and way increasing transformation efficiency of water flow by means of analysis energy losses in hydraulic turbine.

  4. Children's selective trust decisions: rational competence and limiting performance factors.

    Science.gov (United States)

    Hermes, Jonas; Behne, Tanya; Bich, Anna Elisa; Thielert, Christa; Rakoczy, Hannes

    2018-03-01

    Recent research has amply documented that even preschoolers learn selectively from others, preferring, for example, reliable over unreliable and competent over incompetent models. It remains unclear, however, what the cognitive foundations of such selective learning are, in particular, whether it builds on rational inferences or on less sophisticated processes. The current study, therefore, was designed to test directly the possibility that children are in principle capable of selective learning based on rational inference, yet revert to simpler strategies such as global impression formation under certain circumstances. Preschoolers (N = 75) were shown pairs of models that either differed in their degree of competence within one domain (strong vs. weak or knowledgeable vs. ignorant) or were both highly competent, but in different domains (e.g., strong vs. knowledgeable model). In the test trials, children chose between the models for strength- or knowledge-related tasks. The results suggest that, in fact, children are capable of rational inference-based selective trust: when both models were highly competent, children preferred the model with the competence most predictive and relevant for a given task. However, when choosing between two models that differed in competence on one dimension, children reverted to halo-style wide generalizations and preferred the competent models for both relevant and irrelevant tasks. These findings suggest that the rational strategies for selective learning, that children master in principle, can get masked by various performance factors. © 2017 John Wiley & Sons Ltd.

  5. Plasma triacylglycerol and coagulation factor concentrations predict the anticoagulant effect of dietary fish oil in overweight subjects

    DEFF Research Database (Denmark)

    Vanschoonbeek, Kristof; Feijge, Marion A H; Saris, Wim H M

    2007-01-01

    fish-oil effects. In study 1, 54 overweight subjects consumed 3.1 g (n-3) PUFA daily. In study 2, which involved 42 overweight patients with type 2 diabetes, 20 subjects consumed (n-3) PUFA, whereas 22 others ingested a preparation rich in (n-6) PUFA. Tissue factor-induced thrombin generation (thrombin...... potential) was determined as an integrated measure of plasma coagulant activity. In both studies, multivariate analysis indicated a strong clustering of fasting concentrations of triacylglycerols, prothrombin, factor V, factor VII, and factor X with one another at baseline. This cluster of factors......-induced lowering of triacylglycerol and coagulation factor V, VII, and X concentrations, and thrombin generation. We conclude that high fasting triacylglycerol concentrations predict high procoagulant activity and a lowering of thrombin potential with dietary fish oil....

  6. Patterns of parasite distribution in the hybrids of non-congeneric cyprinid fish species: is asymmetry in parasite infection the result of limited coadaptation?

    Czech Academy of Sciences Publication Activity Database

    Krasnovyd, V.; Vetešník, Lukáš; Gettová, L.; Civáňová, K.; Šimková, A.

    2017-01-01

    Roč. 47, č. 8 (2017), s. 471-483 ISSN 0020-7519 R&D Projects: GA ČR GAP505/12/0375 Institutional support: RVO:68081766 Keywords : Interspecific hybrids * Cyprinid fish * Parasite communities * Host specificity * Maternal ancestry Subject RIV: EG - Zoology OBOR OECD: Parasitology Impact factor: 3.730, year: 2016

  7. The bioaccumulation factor for phosphorus-32 in edible fish tissue. Final report 1 Aug 77-15 Oct 79

    International Nuclear Information System (INIS)

    Kaho, B.; Turgeon, K.

    1980-03-01

    Information used to derive the bioaccumulation factor for P-32 in edible portions of fish from water was reviewed to evaluate the currently recommended values of 100,000 in fresh water and 29,000 in sea water that are applied in generic calculations of radiation doses to persons from nuclear power reactor effluents. A phosphorus bioaccumulation factor of 70,000 was calculated for larger rivers and estuarine waters on the basis of geometric mean phosphorus concentrations of 2 mg/g wet weight in fish muscle and 0.03 mg/1 dissolved in water. A bioaccumulation factor for P-32 of 3,000 was computed by multiplying the phosphorus bioaccumulation factor by the ratio of the biological to the effective turnover rate in fish muscle. A biological turnover rate in muscle of 0.2 percent per day was estimated from phosphorus balances as a long-term average for large fish, although more rapid turnovers have been observed for brief periods. Large deviations from these selected generic bioaccumulation factors occur because of differences in phosphorus concentrations and turnover rates. Bioaccumulation of this magnitude is due to P-32 concentration at lowest trophic levels in the food web, not by concentration in fish, hence the availability of concentrating organisms determines whether this bioaccumulation factor is reached. Several other conditions that affect the P-32 bioaccumulation factor have not been quantified but are suggested for study. Measurement programs are recommended to determine site-specific P-32 bioaccumulation factors and enlarge the data base for the generic values

  8. Feed intake and oxygen consumption in fish

    NARCIS (Netherlands)

    Subramanian, S.

    2013-01-01

    In fish, the voluntary feed intake is influenced by dietary, environmental and/or physiological factors. It is well known that under hypoxia the concentration of oxygen in the water (DO) determines the feed intake of fish. However at non-limiting water DO levels (normoxia), several other

  9. Influence of temporal and spatial factors on abundance and richness of fish early stages in shallow tropical estuaries

    NARCIS (Netherlands)

    Arévalo-Frías, W.; Mendoza-Carranza, M.

    2015-01-01

    Accurate determination of abundance and richness of fish early stages in estuarine zones is critical to support management and protection plans; it is therefore necessary to consider all influential factors. Habitat diversity, seasonality, moon phase and diel variations, and their interactions are

  10. Towards improved behavioural testing in aquatic toxicology: Acclimation and observation times are important factors when designing behavioural tests with fish.

    Science.gov (United States)

    Melvin, Steven D; Petit, Marie A; Duvignacq, Marion C; Sumpter, John P

    2017-08-01

    The quality and reproducibility of science has recently come under scrutiny, with criticisms spanning disciplines. In aquatic toxicology, behavioural tests are currently an area of controversy since inconsistent findings have been highlighted and attributed to poor quality science. The problem likely relates to limitations to our understanding of basic behavioural patterns, which can influence our ability to design statistically robust experiments yielding ecologically relevant data. The present study takes a first step towards understanding baseline behaviours in fish, including how basic choices in experimental design might influence behavioural outcomes and interpretations in aquatic toxicology. Specifically, we explored how fish acclimate to behavioural arenas and how different lengths of observation time impact estimates of basic swimming parameters (i.e., average, maximum and angular velocity). We performed a semi-quantitative literature review to place our findings in the context of the published literature describing behavioural tests with fish. Our results demonstrate that fish fundamentally change their swimming behaviour over time, and that acclimation and observational timeframes may therefore have implications for influencing both the ecological relevance and statistical robustness of behavioural toxicity tests. Our review identified 165 studies describing behavioural responses in fish exposed to various stressors, and revealed that the majority of publications documenting fish behavioural responses report extremely brief acclimation times and observational durations, which helps explain inconsistencies identified across studies. We recommend that researchers applying behavioural tests with fish, and other species, apply a similar framework to better understand baseline behaviours and the implications of design choices for influencing study outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Fish stock assessment under data limitations developing a new method based on a size-structured theoretical ecology framework

    DEFF Research Database (Denmark)

    Kokkalis, Alexandros

    catch is known, important quantities about the stock (e.g. biomass of spawners, recruitment) can be quantified. The method is tested using simulated data and validated using a subset of available data from data-rich fish stocks. The implementation of the method as a software package in the R programming......Fish stock assessment is an integral part of every fisheries management system. Modern assessment methods require data about the fishery and the stock, such as catches, survey estimates, aging information and life history parameters, all of which is difficult and expensive to gather. However......, the majority of global fish catches comes from species that lack an official assessment due to lack of data. That is true especially for small scale fisheries and fisheries in developing countries. New methods are in need that require little amount of easily attainable data and provide scientific advice...

  12. Factors affecting farmers' adoption of integrated rice-fish farming systems in the Mekong delta, Vietnam

    NARCIS (Netherlands)

    Bosma, R.H.; Nhan, D.K.; Udo, H.M.J.; Kaymak, U.

    2012-01-01

    This study investigated the determinants of the adoption of improved rice–fish farming systems in the Mekong delta to support policy making, agricultural land-use planning and extension of integrated rice–fish farming. Recently these systems have been referred to as adaptations to climate change,

  13. Radiocaesium in lake fishes - pre and post Chernobyl evaluation of transfer factors from deposition

    International Nuclear Information System (INIS)

    Dominici, G.; Malvicini, A.

    1991-01-01

    The amounts and concentration of radiocaesium in fishes and in lake water, taken from major lakes in the Varese region for the periods pre and post Chernobyl are reported. Some relationships are obtained which permit to forecast the intake on behalf of the fishes knowing the quantity of radioactivity entering into the lake bed. (15 tabs; 18 figs)

  14. Important variations in parvalbumin content in common fish species: a factor possibly contributing to variable allergenicity.

    Science.gov (United States)

    Kuehn, A; Scheuermann, T; Hilger, C; Hentges, F

    2010-01-01

    Although 95% of fish-allergic patients are sensitized to the major fish allergen parvalbumin, clinical reactions to different fish species vary considerably in symptoms, intensity and frequency in allergic subjects. This study aimed at the quantification of parvalbumin levels in salmon, trout, cod, carp, mackerel, herring, redfish and tuna. Fish muscle extracts were separated by SDS-PAGE and parvalbumin content was estimated by densitometric band quantification. Individual antisera were raised in BALB/c mice against parvalbumins purified from seven fish species. Parvalbumin content was quantified in fish (raw/processed) and skin prick test (SPT) solutions by ELISA using the corresponding anti-serum for detection and the purified parvalbumins as standards. Using SDS-PAGE scanning, parvalbumin contents were 2 mg for cod, carp, redfish and herring. Using ELISA, parvalbumin content ranged from 2.5 mg per gram raw muscle for carp, herring and redfish. The parvalbumin content of processed samples (cooked/commercial) was 20-60% lower. Allergen content in SPT samples ranged from 20 to 70 μg parvalbumin/ml of extract. No parvalbumin was found in tuna SPT solution. The parvalbumin content of most commonly consumed fish species varies considerably. Differences range from severalfold to one hundredfold. This has to be taken into account when designing food challenge tests and advising fish-allergic patients. Copyright © 2010 S. Karger AG, Basel.

  15. Histamine fish poisoning revisited.

    Science.gov (United States)

    Lehane, L; Olley, J

    2000-06-30

    Histamine (or scombroid) fish poisoning (HFP) is reviewed in a risk-assessment framework in an attempt to arrive at an informed characterisation of risk. Histamine is the main toxin involved in HFP, but the disease is not uncomplicated histamine poisoning. Although it is generally associated with high levels of histamine (> or =50 mg/100 g) in bacterially contaminated fish of particular species, the pathogenesis of HFP has not been clearly elucidated. Various hypotheses have been put forward to explain why histamine consumed in spoiled fish is more toxic than pure histamine taken orally, but none has proved totally satisfactory. Urocanic acid, like histamine, an imidazole compound derived from histidine in spoiling fish, may be the "missing factor" in HFP. cis-Urocanic acid has recently been recognised as a mast cell degranulator, and endogenous histamine from mast cell degranulation may augment the exogenous histamine consumed in spoiled fish. HFP is a mild disease, but is important in relation to food safety and international trade. Consumers are becoming more demanding, and litigation following food poisoning incidents is becoming more common. Producers, distributors and restaurants are increasingly held liable for the quality of the products they handle and sell. Many countries have set guidelines for maximum permitted levels of histamine in fish. However, histamine concentrations within a spoiled fish are extremely variable, as is the threshold toxic dose. Until the identity, levels and potency of possible potentiators and/or mast-cell-degranulating factors are elucidated, it is difficult to establish regulatory limits for histamine in foods on the basis of potential health hazard. Histidine decarboxylating bacteria produce histamine from free histidine in spoiling fish. Although some are present in the normal microbial flora of live fish, most seem to be derived from post-catching contamination on board fishing vessels, at the processing plant or in the

  16. Fish health and fish quality

    DEFF Research Database (Denmark)

    Ingerslev, Hans-Christian

    Aquaculture is an expanding worldwide industry producing an increasing amount of fish every year. The quality of the fish meat is dependent upon many biological and non-biological factors. Infectious diseases are known to cause bleedings and damage of the muscle tissue that may lead to scarring...... are poorly described in fish. The present work in this thesis focused on: 1) examination of potential changes in the quality regarding texture of the muscle tissue in rainbow trout (Oncorhynchus mykiss) after previous infection with the bacterial pathogens Yersinia ruckeri and Vibrio anguillarum; 2...... of these studies showed that previous infections by Yersinia ruckeri and Vibrio anguillarum gave rise to subsequent changes regarding textural quality parameters in fresh fish meat, while no differences were seen for cold-smoked meat from the same fish. The texture in previous infected fish was less flaky and less...

  17. Lake Roosevelt Fisheries Evaluation Program; Evaluation of Limiting Factors for Stocked Kokanee and Rainbow Trout in Lake Roosevelt, Washington, 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, Casey; Polacek, Matt

    2009-03-01

    Hatchery supplementation of kokanee Oncorhynchus nerka and rainbow trout O. mykiss has been the primary mitigation provided by Bonneville Power Administration for loss of anadromous fish to the waters above Grand Coulee Dam (GCD). The hatchery program for rainbow trout has consistently met management goals and provided a substantial contribution to the fishery; however, spawner returns and creel survey results for kokanee have been below management goals. Our objective was to identify factors that limit limnetic fish production in Lake Roosevelt by evaluating abiotic conditions, food limitations, piscivory, and entrainment. Dissolved oxygen concentration was adequate throughout most of the year; however, levels dropped to near 6 mg/L in late July. For kokanee, warm water temperatures during mid-late summer limited their nocturnal distribution to 80-100 m in the lower section of the reservoir. Kokanee spawner length was consistently several centimeters longer than in other Pacific Northwest systems, and the relative weights of rainbow trout and large kokanee were comparable to national averages. Large bodied daphnia (> 1.7 mm) were present in the zooplankton community during all seasons indicating that top down effects were not limiting secondary productivity. Walleye Stizostedion vitreum were the primary piscivore of salmonids in 1998 and 1999. Burbot Lota lota smallmouth bass Micropterus dolomieui, and northern pikeminnow Ptychocheilus oregonensis preyed on salmonids to a lesser degree. Age 3 and 4 walleye were responsible for the majority (65%) of the total walleye consumption of salmonids. Bioenergetics modeling indicated that reservoir wide consumption by walleye could account for a 31-39% loss of stocked kokanee but only 6-12% of rainbow trout. Size at release was the primary reason for differential mortality rates due to predation. Entrainment ranged from 2% to 16% of the monthly abundance estimates of limnetic fish, and could account for 30% of total

  18. Mortality of centrarchid fishes in the Potomac drainage: survey results and overview of potential contributing factors.

    Science.gov (United States)

    Blazer, V S; Iwanowicz, L R; Starliper, C E; Iwanowicz, D D; Barbash, P; Hedrick, J D; Reeser, S J; Mullican, J E; Zaugg, S D; Burkhardt, M R; Kelble, J

    2010-09-01

    Skin lesions and spring mortality events of smallmouth bass Micropterus dolomieu and selected other species were first noted in the South Branch of the Potomac River in 2002. Since that year morbidity and mortality have also been observed in the Shenandoah and Monocacy rivers. Despite much research, no single pathogen, parasite, or chemical cause for the lesions and mortality has been identified. Numerous parasites, most commonly trematode metacercariae and myxozoans; the bacterial pathogens Aeromonas hydrophila, Aeromonas salmonicida, and Flavobacterium columnare; and largemouth bass virus have all been observed. None have been consistently isolated or observed at all sites, however, nor has any consistent microscopic pathology of the lesions been observed. A variety of histological changes associated with exposure to environmental contaminants or stressors, including intersex (testicular oocytes), high numbers of macrophage aggregates, oxidative damage, gill lesions, and epidermal papillomas, were observed. The findings indicate that selected sensitive species may be stressed by multiple factors and constantly close to the threshold between a sustainable (healthy) and nonsustainable (unhealthy) condition. Fish health is often used as an indicator of aquatic ecosystem health, and these findings raise concerns about environmental degradation within the Potomac River drainage. Unfortunately, while much information has been gained from the studies conducted to date, due to the multiple state jurisdictions involved, competing interests, and other issues, there has been no coordinated approach to identifying and mitigating the stressors. This synthesis emphasizes the need for multiyear, interdisciplinary, integrative research to identify the underlying stressors and possible management actions to enhance ecosystem health.

  19. Fish assemblages in the Upper Esopus Creek, NY: Current status, variability, and controlling factors

    Science.gov (United States)

    Baldigo, Barry P.; George, Scott D.; Keller, Walter T

    2015-01-01

    The Upper Esopus Creek receives water diversions from a neighboring basin through the Shandaken Tunnel (the portal) from the Schoharie Reservoir. Although the portal is closed during floods, mean flows and turbidity of portal waters are generally greater than in Esopus Creek above their confluence. These conditions could potentially affect local fish assemblages, yet such effects have not been assessed in this highly regulated stream. We studied water quality, hydrology, temperature, and fish assemblages at 18 sites in the Upper Esopus Creek during 2009–2011 to characterize the effects of the portal input on resident-fish assemblages and to document the status of the fishery resource. In general, fish-community richness increased by 2–3 species at mainstem sites near the portal, and median density and biomass of fish communities at sites downstream of the portal were significantly lower than they were at sites upstream of the portal. Median densities of Salmo trutta (Brown Trout) and all trout species were significantly lower than at mainstem sites downstream from the portal—25.1 fish/0.1 ha and 148.9 fish/0.1 ha, respectively—than at mainstem sites upstream from the portal—68.8 fish/0.1 ha and 357.7 fish/0.1 ha, respectively—yet median biomass for Brown Trout and all trout did not differ between sites from both reaches. The median density of young-of-year Brown Trout at downstream sites (9.3 fish/0.1 ha) was significantly lower than at upstream sites (33.9 fish/0.1 ha). Waters from the portal appeared to adversely affect the density and biomass of young-of-year Brown Trout, but lower temperatures and increased flows also improved habitat quality for mature trout at downstream sites during summer. These findings, and those from companion studies, indicate that moderately turbid waters from the portal had few if any adverse impacts on trout populations and overall fish communities in the Upper Esopus Creek during this study.

  20. Risk factors for mobility limitation in community-dwelling older adults: a social ecological perspective.

    Science.gov (United States)

    Yeom, Hye A; Fleury, Julie; Keller, Colleen

    2008-01-01

    Although a variety of risk factors for mobility limitation in older adults have been examined, a collective review of relevant literature has not been reported. The purposes of this review are to report the intrapersonal, interpersonal, environmental, and organizational risk factors related to mobility limitation using a social ecological perspective and to discuss the direction of future clinical practice consistent with current literature on mobility limitation of community-dwelling older adults. Intrapersonal risk factors related to mobility limitation include advanced age, female gender, low socioeconomic status, comorbidity, lack of motivation (i.e., dependent personality, decreased self-efficacy), lifestyle factors (i.e., sedentary lifestyle, smoking, obesity), and physiological factors (i.e., vitamin D deficiency, inflammation, poor nutritional status). Interpersonal risk factors related to mobility limitation include weak social networks and limited social activities. Geriatric clients may also experience a decline in mobility when they encounter environmental challenges such as an inconvenient home environment and lack of availability of services in their community, as well as lack of organizational resources stemming from social policy. Potential intervention strategies focused on modifiable risk factors may include lifestyle modifications, social networking programs, and enhancing awareness of environmental and organizational resources in the community for older adults at risk for mobility limitation.

  1. Neuroendocrine immune interaction in fish: differential regulation of phagocyte activity by neuroendocrine factors

    NARCIS (Netherlands)

    Verburg-van Kemenade, B.M.L.; Ribeiro, C.M.S.; Chadzinska, M.K.

    2011-01-01

    Coping with physical, chemical and biological disturbances depends on an extensive repertoire of physiological, endocrinological and immunological responses. Fish provide intriguing models to study bi-directional interaction between the neuroendocrine and the immune systems. Macrophages and

  2. Recruitment of juvenile fishes into a small temperate choked lagoon (Argentina and the influence of environmental factors during the process

    Directory of Open Access Journals (Sweden)

    Daniel O. Bruno

    2015-03-01

    Full Text Available Juvenile fishes were sampled every 15 days from September 2009 to April 2010 along the marine-estuarine gradient (surf zone, estuary and a freshwater stream of the Mar Chiquita lagoon, Argentina. The temporal variations of juvenile assemblages in spring-summer and the environmental variables related to the spatial and temporal patterns were analysed. Four groups of sampling stations were defined, indicating differences in fish composition among zones during the spring–early summer period (Groups I to III, while the composition of juvenile fishes was homogeneous along the marine-estuarine gradient during the late summer–early autumn period (Group IV. Platanichthys platana and Ramnogaster arcuata (Group A and Odontesthes argentinensis and Brevoortia aureaz (Group B contributed most to the temporal differences observed. The three first species reached this estuarine system in spring, although with lower abundances than in early summer, while B. aurea was dominant in late summer–early autumn, showing different periods of recruitment of these species into the lagoon. After factoring out variation due to shared spatial-temporal-environmental factors (4.43%, canonical correspondence analysis (CCA showed that temporal factors had an almost five times greater contribution (15.15% than spatial factors (2.85% and almost twice as great as the pure environmental factors (8.11% to explaining the variation in abundance of the juvenile fishes. From the significant environmental variables incorporated in the CCA, wind direction contributed more than water temperature, salinity or transparency in explaining data variability. Indeed, most species were related to “onshore winds” and therefore the importance of wind in the successful recruitment of juveniles into this shallow and micro-tidal estuary is discussed.

  3. Driving automation forward : human factors for limited-ability autonomous driving systems.

    Science.gov (United States)

    2010-01-01

    Over the past 100 years, there has been a : steady progression of innovations that : enhance the driving experience, in particular : the continuing trend toward automating more : driving tasks. Human Factors for Limited-Ability : Autonomous Drivin...

  4. Assessment and validation of the CAESAR predictive model for bioconcentration factor (BCF in fish

    Directory of Open Access Journals (Sweden)

    Milan Chiara

    2010-07-01

    Full Text Available Abstract Background Bioconcentration factor (BCF describes the behaviour of a chemical in terms of its likelihood of concentrating in organisms in the environment. It is a fundamental property in recent regulations, such as the European Community Regulation on chemicals and their safe use or the Globally Harmonized System for classification, labelling and packaging. These new regulations consider the possibility of reducing or waiving animal tests using alternative methods, such as in silico methods. This study assessed and validated the CAESAR predictive model for BCF in fish. Results To validate the model, new experimental data were collected and used to create an external set, as a second validation set (a first validation exercise had been done just after model development. The performance of the model was compared with BCFBAF v3.00. For continuous values and for classification purposes the CAESAR BCF model gave better results than BCFBAF v3.00 for the chemicals in the applicability domain of the model. R2 and Q2 were good and accuracy in classification higher than 90%. Applying an offset of 0.5 to the compounds predicted with BCF close to the thresholds, the number of false negatives (the most dangerous errors dropped considerably (less than 0.6% of chemicals. Conclusions The CAESAR model for BCF is useful for regulatory purposes because it is robust, reliable and predictive. It is also fully transparent and documented and has a well-defined applicability domain, as required by REACH. The model is freely available on the CAESAR web site and easy to use. The reliability of the model reporting the six most similar compounds found in the CAESAR dataset, and their experimental and predicted values, can be evaluated.

  5. Transfer Factors of Nuclides for Five Fish Species Inhabiting the Sea near the Yonggwang Nuclear Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Kwangmuk; Choi, Yongho; Jun, In; Kim, Byungho; Keum, Dongkwon [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The IAEA is going to publish a handbook of the TF values of various radionuclides for a number of plant and animal species. However, it is recommended that they be used in case there is no site-specific data. This is because TF values can vary considerably with wild-life species and environmental conditions. Therefore, it is necessary to urgently establish our own database of wild-life transfer factors for use in the wild-life dose assessment probably in the near future. In the present study, TF values of various radionuclides were investigated for several marine fish species living around the Younggwang NPP. It was done by measuring the concentrations of stable isotopes in fish and seawater samples. TF values of 21 nuclides were measured for five fish species inhabiting the sea near the Younggwang NPP. They showed considerable variations with the nuclides and fish species. Determination of TF values needs to be extended to various kinds of domestic wild lives so as to establish an input data file for a Korean assessment model such as K-BIOTA.

  6. Risk factors for persistent airflow limitation: Analysis of 306 patients with asthma

    OpenAIRE

    Wang, Lingcheng; Gao, Shuncui; Zhu, Wei; Su, Jun

    2014-01-01

    Objectives : To determine the risk factors associated with persistent airflow limitation in patients with asthma. Method s: This study was designed and carried out in the department of respiratory medicine, fourth People?s Hospital of Jinan City, Shandong province, China between Jan 2012 and Dec 2012. Three hundred and six asthma patients participating in the study were divided into persistent airflow limitation group (PAFL) and no persistent airflow limitation group (NPAFL). The patients par...

  7. Zebra mussels (Dreissena polymorpha) limit food for larval fish (Pimephales promelas) in turbulent systems: A bioenergetics analysis

    Science.gov (United States)

    Bartsch, L.A.; Richardson, W.B.; Sandheinrich, M.B.

    2003-01-01

    We conducted a factorial experiment, in outdoor mesocosms, on the effects of zebra mussels and water column mixing (i.e., turbulence) on the diet, growth, and survival of larval fathead minnows (Pimephales promelas). Significant (P zebra mussels, whereas mortality was 37% in treatment with turbulence and 17% and 18% in the zebra mussels treatment, and the control, respectively. The size of individual fish was significantly different among treatments at the end of the experiment and was inversely related to survival. Levels of trophic resources (i.e., phyto and zooplankton) varied among treatments and were treatment specific. Turbulent mixing facilitated removal of phytoplankton by zebra mussels by making the entire water column of the tanks available to these benthic filter feeders. Early in the experiment (Day = 0 to 14) the physical process of turbulent mixing likely caused a reduction in standing stocks of zooplankton. The interactive effect of turbulence and mussels reduced copepod and rotifer stocks, through physical processes and through filtration by zebra mussels, relative to the turbulence treatment. The reductions in the number of total zooplankton in the turbulent mixing mesocosms and the further reduction of rotifer and copepod in the turbulence and mussels treatment coincided with a period of increased reliance of larval fathead minnows on these prey. Estimates of consumption from bioenergetics modeling and measured prey standing stocks indicated caloric resources of suitable prey in turbulence treatments during the early weeks of the experiment were insufficient to prevent starvation. Early mortality in the turbulence and mussels treatment likely released surviving fish from intense intraspecific competition and resulted in higher individual growth rates. A combination of high abundance of zebra mussels in an environment with a well-mixed water column can have significant effects on larval fish survival and growth.

  8. Physical factors affecting the abundance and species richness of fishes in the shallow waters of the southern Bothnian Sea (Sweden)

    Science.gov (United States)

    Thorman, Staffan

    1986-03-01

    The relationship between the composition of the fish assemblages and the abiotic environment in seven shallow areas within the same geographical range in the southern Bothnian Sea were studied in May, July, September and November 1982. Eighteen species were found in the areas and the major species were Pungitius pungitius (L.), Pomatoschistus minutus (Pallas), Gasterosteus aculeatus (L.), Phoxinus phoxinus (L.), Pomatoschistus microps (Krøyer) and Gobius niger L. The main purpose of the study was to examine the possible effects of exposure, organic contents in sediments and habitat heterogeneity on species richness and abundance of the assemblages. There was a negative correlation between the organic contents of the sediment and exposure. There were no significant correlations between exposure, organic contents, size of the areas and species numbers but habitat heterogeneity was positively correlated with species number. There were no correlations between fish abundance and heterogeneity of the areas. Negative correlations occurred between the exposure of the areas and fish abundance. The amounts of the pooled benthic fauna were negatively correlated to the exposure. The species/area hypothesis finds no support in the results, because there was no correlation between habitat heterogeneity of an area and its size. The effective fetch combined with the heterogeneity measurement of the areas seemed to be useful indicators of the species composition and fish abundance. Habitat heterogeneity and exposure were the most important structuring factors of these shallow water fish assemblages during the ice-free period and within the local geographical range. The assemblages consist of a mixture of species with marine or limnic origin and they have probably not evolved in the Bothnian Sea or together. They are most likely regulated by their physiological plasticity and not by interactions with other species.

  9. Evolution of hematopoiesis: Three members of the PU.1 transcription factor family in a cartilaginous fish, Raja eglanteria

    Science.gov (United States)

    Anderson, M. K.; Sun, X.; Miracle, A. L.; Litman, G. W.; Rothenberg, E. V.

    2001-01-01

    T lymphocytes and B lymphocytes are present in jawed vertebrates, including cartilaginous fishes, but not in jawless vertebrates or invertebrates. The origins of these lineages may be understood in terms of evolutionary changes in the structure and regulation of transcription factors that control lymphocyte development, such as PU.1. The identification and characterization of three members of the PU.1 family of transcription factors in a cartilaginous fish, Raja eglanteria, are described here. Two of these genes are orthologs of mammalian PU.1 and Spi-C, respectively, whereas the third gene, Spi-D, is a different family member. In addition, a PU.1-like gene has been identified in a jawless vertebrate, Petromyzon marinus (sea lamprey). Both DNA-binding and transactivation domains are highly conserved between mammalian and skate PU.1, in marked contrast to lamprey Spi, in which similarity is evident only in the DNA-binding domain. Phylogenetic analysis of sequence data suggests that the appearance of Spi-C may predate the divergence of the jawed and jawless vertebrates and that Spi-D arose before the divergence of the cartilaginous fish from the lineage leading to the mammals. The tissue-specific expression patterns of skate PU.1 and Spi-C suggest that these genes share regulatory as well as structural properties with their mammalian orthologs.

  10. Effects of social factors on fishing effort: The case of the Philippine tuna purse seine fishery

    NARCIS (Netherlands)

    Libre, S.V.D.; Voorn, van G.A.K.; Broeke, Ten G.A.; Bailey, M.L.; Berentsen, P.B.M.; Bush, S.R.

    2015-01-01

    High fishing effort remains in many of the world’s fisheries despite a variety of policies that have been implemented to reduce it. These policies have predominantly focused on models of cause and effect that ignore the possibility that the intended outcomes are altered by social behavior and

  11. Bioaccumulation factor for I-131 in aquatic biota II fish - tilapia (Tilapia Mossambica)

    International Nuclear Information System (INIS)

    Garcia, G.F.; Casyao, J.M.; Bautista, E.Rb.

    1982-01-01

    The study was undertaken to provide local values for an essential parameter in the estimation of the dose contribution of I-131 through ingestion of fresh water fish. The result showed that the tilapia used in the experiment did not vary significantly in weight and no definite conclusion can be derived as to the effect of body size to bioaccumulation of I-131. (ELC)

  12. Diet and lifestyle factors associated with fish consumption in men and women: a study of whether gender differences can result in gender-specific confounding

    Directory of Open Access Journals (Sweden)

    Wennberg Maria

    2012-12-01

    Full Text Available Abstract Background Fish consumption and intake of omega-3 fatty acids from fish are associated with a lower risk of cardiovascular disease. However, a prospective study from northern Sweden showed that high consumption of fish is associated with an increased risk of stroke in men, but not in women. The current study aimed to determine if fish consumption is differently related to lifestyle in men compared with women in northern Sweden. Methods Lifestyle information on 32,782 men and 34,866 women (aged 30–60 years was collected between 1992 and 2006 within the Västerbotten Intervention Programme (a health intervention in northern Sweden. Spearman correlations coefficients (Rs were calculated between self-reported consumption of fish and other food items. Lifestyle variables were compared between fish consumption categories. Results Fish consumption was positively associated with other foods considered healthy (e.g., root vegetables, lettuce/cabbage/spinach/broccoli, chicken, and berries; Rs = 0.21-0.30, as well as with other healthy lifestyle factors (e.g., exercise and not smoking and a higher educational level, in both men and women. The only gender difference found, concerned the association between fish consumption and alcohol consumption. Men who were high consumers of fish had a higher intake of all types of alcohol compared with low to moderate fish consumers. For women, this was true only for wine. Conclusions Except for alcohol, the association between fish consumption and healthy lifestyle did not differ between men and women in northern Sweden. It is important to adjust for other lifestyle variables and socioeconomic variables in studies concerning the effect of fish consumption on disease outcome.

  13. Good news for conservation: mitochondrial and microsatellite DNA data detect limited genetic signatures of inter-basin fish transfer in Thymallus thymallus (Salmonidae from the Upper Drava River

    Directory of Open Access Journals (Sweden)

    Meraner A.

    2013-06-01

    Full Text Available In the last few decades, numerous populations of European grayling, Thymallus thymallus, have been suffering from stocking-induced genetic admixture of foreign strains into wild populations. Concordantly, genetic introgression was also reportedfor grayling stocks inhabiting the Upper Drava River, but all published genetic data based on specimens caught at least a decade ago, when stocking load was strong. Here, we applied mitochondrial control region sequencing and nuclear microsatellite genotyping to Upper Drava grayling fry collections and reference samples to update patterns and extent of human-mediated introgression. In contrast to previous data, we highlighted an almost genetic integrity of Drava grayling, evidencing limited genetic signatures of trans-basin stocking for grayling of Northern Alpine Danubian origin. Recent hybridisation was detected only twice among sixty-nine samples, while several cases of later-generation hybrids were disclosed by linking mitochondrial sequence to nuclear genetic data. The observed past, but very limited recent genetic introgression in grayling from Upper Drava seems to reflect shifting stocking trends, changing from massive introduction of trans-basin fish to more conservation-oriented strategies during the last 27 years. In a conservation context, we encourage pursuing the use of local wild grayling for supportive- and captive-breeding, but underline the need for genetic approaches in brood-stock selection programs. Finally, our integrated results from sibship reconstruction validate our strictly fry-based sampling scheme, thus offering a reasonable alternative also for other rheophilic fish species with similar life-history characteristics.

  14. Limiting factor analysis of high availability nuclear plants (boiling water reactors). Final report

    International Nuclear Information System (INIS)

    Frederick, L.G.; Brady, R.M.; Shor, S.W.W.; McCusker, J.T.; Alden, W.M.; Kovacs, S.

    1979-08-01

    The pertinent results are presented of a 16-month study conducted for Electric Power Research Institute by General Electric Company, Bechtel Power Corporation, and Philadelphia Electric Company. The study centered around the Peach Bottom 2 Atomic Power Station, but also included limited study of operations at 20 additional operating boiling water reactors. The purpose of the study was to identify and evaluate key factors limiting plant availability, and to identify potential improvements for eliminating or alleviating those limitations. The key limiting factors were found to be refueling activities; activities related to the reactor fuel; reactor scrams; activities related to 20 operating systems or major components; delays due to radiation, turbid water during refueling operations, facilities/working conditions, and dirt/foreign material; and general maintenance/repair of valves and piping. Existing programs to reduce the effect on plant unavailability are identified, and suggestions for further action are made

  15. Fish population dynamics

    National Research Council Canada - National Science Library

    Gulland, J. A

    1977-01-01

    This book describes how the dynamics of fish populations can be analysed in terms of the factors affecting their rates of growth, mortality and reproduction, with particular emphasis on the effects of fishing...

  16. Soil types and limiting factors in agricultural production in the San Fernando district, Tamaulipas, Mexico

    International Nuclear Information System (INIS)

    Espinosa Ramirez, M.; Garza Cedillo, R.; Andrade limas, E.; Belmonte Serrato, F.

    2009-01-01

    The limiting factors in agricultural production, defined as those properties and characteristics of the geographical environment that influence the development of crops, can be diverse and are grouped with the physical environment of soil. They are the result of soil characteristics and soil degradation processes by anthropogenic influence. Due to the above, the objective of this study was to identify and surveying the limitative factors to agricultural production, as well as to define its ability land use capacity in San Fernando district, Tamaulipas. (Author) 7 refs.

  17. Factors that affect riverines territorial behavior on fishing environments in flooding areas, Low Solimões, Central Amazonia, Brazil

    Directory of Open Access Journals (Sweden)

    Jorge Iván Sánchez-Botero

    2010-12-01

    Full Text Available Flooding areas present high biological productivity and are inhabited by populations that practice agriculture-fishing activities, based on the multiple use of resources. The economicity of the system leads the riverines to territorial appropriation and the common dependence of the resources leads to the establishment of internal agreements, defining criteria of access and intensity of extraction. This study, through 244 interviews with fishermen and meetings at 16 communities of Low Solimões River, identified factors that influence on the magnitude and purpose of the fisheries, especially at common use fishing spots, describing appropriation mechanisms and conflicts. The studied area comprehends two systems of terra firme and one of flooding lakes. For subsistence and commercial fisheries was estimated the area, extension, and frequency of use for period of the year (dry/flood. Each community explored the fishing environments depending on the proximity and/or accessibility, revealing uses inside its territorial delimitations, with superposing on that explored for subsistence and commercial means. There are conflicts with commercial and sporting fisheries, fishermen out from the region and farmers. Prohibitions or access control don't exist to the igapós systems, but informal rules regulating the use. Three sceneries are proposed for the integrated management of the systems in the area, due to the diversity of environments and interests of the involved groups.

  18. Salinity as the main factor structuring small-bodied fish assemblages in hydrologically altered Mediterranean coastal lagoons

    Directory of Open Access Journals (Sweden)

    Sílvia Rodríguez-Climent

    2013-03-01

    Full Text Available In the Ebro Delta coastal lagoons, one of the main anthropogenic pressures is the artificial freshwater input. Each coastal lagoon has different water management schemes causing profound changes in its physicochemical characteristics. The main objective of this water management is to favour some bird species with interest either for conservation or hunting activities. The present study assesses the influence of hydrological alteration on the fish assemblages of three coastal lagoons in the Ebro Delta. The small-bodied fish fauna was mainly composed of five families: Gobiidae, Poecilidae, Cyprinodontidae, Atherinidae and Mugilidae. Salinity was found to be the main factor structuring fish community in the lagoons. The dominant species was the common goby (Pomatochistus microps when the lagoons reached higher salinity values, whereas the invasive eastern mosquitofish (Gambusia holbrooki dominated during the period of higher freshwater inputs. The juveniles of the family Mugilidae showed low catch per unit effort, especially during the period of lower salinity. This same pattern was found for the endangered Spanish toothcarp (Aphanius iberus. Overall, introduced species were favoured by low salinity, which highlights the importance of changing the present water management by reducing the freshwater inputs in order to maintain suitable levels of salinity to favour native species that are important for both commercial and conservation purposes.

  19. Comparison of cadmium and chromium bioconcentration factors between scaled and scale less fish species: common carp and sutchi (striped catfish

    Directory of Open Access Journals (Sweden)

    Sideh Zainab Abedi

    2014-10-01

    Full Text Available Background: Water-borne, indissoluble heavy metals are bioaccumulated in fish (human food source. In this research, chromium (Cr and cadmium (Cd bioconcentration factors (BCFs in the skin, gills, scales, livers and muscles of two widely-consumed fish species, scaled common carp Cyprinus carpio and scaleless catfish Pangasius hypophthalmus were compared. Material and Methods: Lethal concentrations of Cd and Cr (64.89 & 7.46, and 84.8 & 17.05 mg/L for the catfish and carp, respectively were determined during 96 hrs (96 h LC50, and the fishes were exposed for 15 days. Then the tissue samples were chemically digested and the contents of Cd and Cr were determined using atomic absorption. Results: Total contents of Cr and Cd in the catfish's tissues were 2286.11 & 360.73, and those of Cr & Cd in carp were 734.71 & 725.67 μg/g.dw (excluding the scales, respectively. Metal concentrations in the water residues (day 15 revealed lower Cr and Cd (0.059 & 0.0036 mg/L in the catfish than those in the carp media (0.1 & 0.0412 mg/L, respectively. In common carp, BCF of Cd was as liver > skin > gills > muscle > scales, and those in the catfish marked as liver>muscle >gills >skin. The BCF of Cr in common carp ranked as gills>liver>skin>scales>muscle, and the catfish showing a BCF pattern of Cr as liver> muscle>skin>gills. Conclusion: This study signifies that small amounts of cadmium and chromium with high BCFs especially in the muscles of scale less fish (catfish threat consumers’ health.

  20. JOB BEHAVIORAL FACTORS AND TURNOVER INTENTION: EVIDENCE FROM SIME DARBY PROPERTY LIMITED

    OpenAIRE

    Amran Awang; Abdul Razak Amir; Wirda Osman

    2013-01-01

    Some job behavioral factors are utilized to examine their relationship with turnover intention among 201 employees in Sime Darby Property (Malaysia) Limited. Job satisfaction, job stress, organizational commitment, job enrichment and person-organization fit are the job behavioral factors selected for the study. The variables used in the study justify the reliability scores consistent with indicators in previous studies. Research methodology justifies the quantitative requirements ...

  1. The influence of the key limiting factors on the limitations of heat transfer in heat pipes with various working fluids

    Directory of Open Access Journals (Sweden)

    Melnyk R. S.

    2017-04-01

    Full Text Available Aluminium and copper heat pipes with grooved and metal fibrous capillary structure are high effective heat transfer devices. They are used in different cooling systems of electronic equipment like a LED modules, microprocessors, receive-transmit modules and so on. However thus heat pipes have heat transfer limitations. There are few types of this limitations: hydraulic limitation, boiling limitation, liquid entrainment by vapor flow and sonic limitation. There is necessity to know which one of these limitations is determinant for heat pipe due to design process. At a present article calculations of maximum heat transfer ability represented. All these calculations were made for LED cooling by using heat pipes with grooved and metal fibrous capillary structures. Pentane, acetone, isobutane and water were used as a coolants. It was shown that the main operation limit for axial grooved heat pipe, which determinate maximum heat transfer ability due to inclination angle for location of cooling zone higher than evaporation zone case, is entrainment limit for pentane and acetone coolants. Nevertheless, for isobutane coolant the main limitation is a boiling limit. However, for heat pipes with metal fibrous capillary structure the main limitation is a capillary limit. This limitation was a determinant for all calculated coolants: water, pentane and acetone. For high porosity range of capillary structure, capillary limit transfer to sonic limit for heat pipes with water, that means that the vapor velocity increases to sonic velocity and can't grow any more. Due to this, coolant cant in a needed quantity infill condensation zone and the last one drained. For heat pipes with acetone and pentane, capillary limit transfer to boiling limit. All calculations were made for vapor temperature equal to 50°C, and for porosity range from 30% to 90%.

  2. Study in situ of the natural uranium, 60 Co and 137 Cs bioaccumulation factor in fish (Cyprinus carpio)

    International Nuclear Information System (INIS)

    Todoran, A.; Toma, A.; Dulama, C.; Horhoianu, V.; Hirica, O.; Patriche, N.; Tenciu, M.; Talpes, M.; Cristea, V.

    2006-01-01

    The paper presents the results of the 'in situ' research, aiming to determine the bioaccumulation factor of natural uranium, 60 Co and 137 Cs in fish (Cyprinus carpio) - the find link in aquatic ecosystems. The work performed is a part of a radioecological study achieved in the experimental pool of S.C.N. Pitesti. The objective of the research was to evaluate the release of the radioactive materials in the environment as well as to establish the transfer mechanisms of the radionuclides in the trophic chains from the aquatic ecosystem. (authors)

  3. Study in situ of the natural uranium, 60 Co and 137 Cs bioaccumulation factor in fish (Cyprinus carpio)

    Energy Technology Data Exchange (ETDEWEB)

    Todoran, A.; Toma, A.; Dulama, C.; Horhoianu, V.; Hirica, O. [Institute for Nuclear Research, Pitesti (Romania); Patriche, N.; Tenciu, M.; Talpes, M. [CPPPPIP, Galati (Romania); Cristea, V. [Galati Univ. (Romania)

    2006-07-01

    The paper presents the results of the 'in situ' research, aiming to determine the bioaccumulation factor of natural uranium, {sup 60}Co and {sup 137}Cs in fish (Cyprinus carpio) - the find link in aquatic ecosystems. The work performed is a part of a radioecological study achieved in the experimental pool of S.C.N. Pitesti. The objective of the research was to evaluate the release of the radioactive materials in the environment as well as to establish the transfer mechanisms of the radionuclides in the trophic chains from the aquatic ecosystem. (authors)

  4. Exploration of factors limiting biomass estimation by polarimetric radar in tropical forests

    NARCIS (Netherlands)

    Quiñones Fernández, M.J.; Hoekman, D.H.

    2004-01-01

    Direct inversion of radar return signals for forest biomass estimation is limited by signal saturation at medium biomass levels (roughly 150 ton/ha for P-band). Disturbing factors such as forest structural differences-and, notably, at low biomass levels, terrain roughness, and soil moisture

  5. Lifestyle Factors and Incident Mobility Limitation in Obese and Non-obese Older Adults.

    NARCIS (Netherlands)

    Koster, A.; Penninx, B.W.J.H.; Newman, A.B.; Visser, M.; van Gool, C.H.; Harris, T.B.; van Eijk, J.T.; Kempen, G.I.; Brach, J.S.; Simonsick, E.M.; Houston, D.K.; Tylavsky, F.A.; Rubin, S.M.; Kritchevsky, S.B.

    2007-01-01

    Objective: This study examines the association between incident mobility limitation and 4 lifestyle factors: smoking, alcohol intake, physical activity, and diet in well-functioning obese (n = 667) and non-obese (n = 2027) older adults. Research Methods and Procedures: Data were from men and women,

  6. What is the most prominent factor limiting photosynthesis in different layers of a greenhouse cucumber canopy?

    NARCIS (Netherlands)

    Chen, T.W.; Henke, M.; Visser, de P.H.B.; Buck-Sorlin, G.H.; Wiechers, D.; Kahlen, K.; Stützel, H.

    2014-01-01

    Background and Aims Maximizing photosynthesis at the canopy level is important for enhancing crop yield, and this requires insights into the limiting factors of photosynthesis. Using greenhouse cucumber (Cucumis sativus) as an example, this study provides a novel approach to quantify different

  7. Scientific Study of Malnutrition as a Limiting Factor in the Development of Education.

    Science.gov (United States)

    Picasso de Oyague, Alfredo

    This study on malnutrition as a limiting factor in the development of education (and, hence, in socioeconomic development generally) was presented to the UNESCO Seminar on Education, Nutrition, Agriculture and Man. The paper reports on recent research showing that the development of the central nervous system in very young children (including the…

  8. Enhanced production of recombinant nattokinase in Bacillus subtilis by the elimination of limiting factors.

    Science.gov (United States)

    Chen, Po Ting; Chao, Yun-Peng

    2006-10-01

    By systematic investigation, glutamate and a mixture of metal ions were identified as factors limiting the production of nattokinase in Bacillus subtilis. Consequently, in medium supplemented with these materials, the recombinant strain secreted 4 times more nattokinase (260 mg l(-1)) than when grown in the unsupplemented medium.

  9. Data-Limited Population-Status Evaluation of Two Coastal Fishes in Southern Angola Using Recreational Catch Length-Frequency Data.

    Science.gov (United States)

    Beckensteiner, Jennifer; Kaplan, David M; Potts, Warren M; Santos, Carmen V; O'Farrell, Michael R

    2016-01-01

    Excessive truncation of a population's size structure is often identified as an important deleterious effect of exploitation, yet the effect on population persistence of size-structure truncation caused by exploitation is often not quantified due to data limitations. In this study, we estimate changes in eggs per recruit (EPR) using annual length-frequency samples over a 9 year period to assess persistence of the two most important recreational fishes in southern Angola: west coast dusky kob (Argyrosomus coronus) and leerfish (Lichia amia). Using a length- and age-structured model, we improve on an existing method to fit this type of model to length-frequency data and estimate EPR. The objectives of the methodological changes are to add flexibility and robustness to the approach for assessing population status in data-limited situations. Results indicate that dusky kob presents very low levels of EPR (5%-10% of the per recruit reproductive capacity in the absence of fishing) in 2013, whereas large inter-annual variability in leerfish estimates suggest caution must be applied when drawing conclusions about its exploitation status. Using simulated length frequency data with known parameter values, we demonstrate that recruitment decline due to overexploitation leads to overestimation of EPR values. Considering the low levels of EPR estimated for the study species, recruitment limitation is not impossible and true EPR values may be even lower than our estimates. It is, therefore, likely that management action, such as the creation of Marine Protected Areas, is needed to reconstitute the west coast dusky kob population.

  10. Fish Allergy

    Science.gov (United States)

    ... Cause Blog Vision Awards Common Allergens Fish Allergy Fish Allergy Learn about fish allergy, how to read ... that you must avoid both. Allergic Reactions to Fish Finned fish can cause severe and potentially life- ...

  11. The Nutraceutical Bioavailability Classification Scheme: Classifying Nutraceuticals According to Factors Limiting their Oral Bioavailability.

    Science.gov (United States)

    McClements, David Julian; Li, Fang; Xiao, Hang

    2015-01-01

    The oral bioavailability of a health-promoting dietary component (nutraceutical) may be limited by various physicochemical and physiological phenomena: liberation from food matrices, solubility in gastrointestinal fluids, interaction with gastrointestinal components, chemical degradation or metabolism, and epithelium cell permeability. Nutraceutical bioavailability can therefore be improved by designing food matrices that control their bioaccessibility (B*), absorption (A*), and transformation (T*) within the gastrointestinal tract (GIT). This article reviews the major factors influencing the gastrointestinal fate of nutraceuticals, and then uses this information to develop a new scheme to classify the major factors limiting nutraceutical bioavailability: the nutraceutical bioavailability classification scheme (NuBACS). This new scheme is analogous to the biopharmaceutical classification scheme (BCS) used by the pharmaceutical industry to classify drug bioavailability, but it contains additional factors important for understanding nutraceutical bioavailability in foods. The article also highlights potential strategies for increasing the oral bioavailability of nutraceuticals based on their NuBACS designation (B*A*T*).

  12. Role of socio-cultural and economic factors in cyprinid fish distribution networks and consumption in Lawa Lake region, Northeast Thailand: Novel perspectives on Opisthorchis viverrini transmission dynamics.

    Science.gov (United States)

    Kim, Christina Sunyoung; Smith, John F; Suwannatrai, Apiporn; Echaubard, Pierre; Wilcox, Bruce; Kaewkes, Sasithorn; Sithithaworn, Paiboon; Sripa, Banchob

    2017-06-01

    Opisthorchis viverrini (Ov) is a fish-borne parasite endemic in parts of Lao PDR, Cambodia, southern Vietnam and Northeast Thailand (Isaan) where an estimated 10 million people are infected. Human Ov infection, associated with hepatobiliary complications, including cholangiocarcinoma (CCA), occurs when infected fish are consumed raw or undercooked, a longstanding cultural tradition in the region. This mixed- methods descriptive study was carried out in Isaan villages around Lawa Lake, Khon Kaen Province, known for their Ov endemicity. Focus group discussions (FGDs) and in depth interviews (IDIs) were used to explore socio-cultural determinants underlying raw fish consumption practices, and global positioning system (GPS) devices to map local fish distribution networks. Qualitative data affirmed major socio-cultural and dietary lifestyle transitions occurring consequent on recent decades of modernization policies and practices, but also the persistence of Isaan traditional raw-fish eating practices and incorrect beliefs about infection risk avoidance. Fish traders/middlemen purchase most of the catch at the lakeshore and play the dominant role in district market fish distribution networks, at least for the larger and less likely infected, fish species. The lower economic value of the small potentially-infected cyprinid fish means local fishermen typically distribute them free, or sell cheaply, to family and friends, effectively concentrating infection risk in already highly Ov infected villages. Our study confirmed the persistence of traditional Isaan raw-fish meal practices, despite major ongoing socio-cultural lifestyle transitions and decades of Ov infection health education programs. We contend that diffuse socio-cultural drivers underpin this practice, including its role as a valued cultural identity marker. A "fish economics" factor was also evident in the concentration of more likely infected fish back into local villages due to their low economic value at

  13. Factors Affecting Mercury Stable Isotopic Distribution in Piscivorous Fish of the Laurentian Great Lakes.

    Science.gov (United States)

    Lepak, Ryan F; Janssen, Sarah E; Yin, Runsheng; Krabbenhoft, David P; Ogorek, Jacob M; DeWild, John F; Tate, Michael T; Holsen, Thomas M; Hurley, James P

    2018-03-06

    Identifying the sources of methylmercury (MeHg) and tracing the transformations of mercury (Hg) in the aquatic food web are important components of effective strategies for managing current and legacy Hg sources. In our previous work, we measured stable isotopes of Hg (δ 202 Hg, Δ 199 Hg, and Δ 200 Hg) in the Laurentian Great Lakes and estimated source contributions of Hg to bottom sediment. Here, we identify isotopically distinct Hg signatures for Great Lakes trout ( Salvelinus namaycush) and walleye ( Sander vitreus), driven by both food-web and water-quality characteristics. Fish contain high values for odd-isotope mass independent fractionation (MIF) with averages ranging from 2.50 (western Lake Erie) to 6.18‰ (Lake Superior) in Δ 199 Hg. The large range in odd-MIF reflects variability in the depth of the euphotic zone, where Hg is most likely incorporated into the food web. Even-isotope MIF (Δ 200 Hg), a potential tracer for Hg from precipitation, appears both disconnected from lake sedimentary sources and comparable in fish among the five lakes. We suggest that similar to the open ocean, water-column methylation also occurs in the Great Lakes, possibly transforming recently deposited atmospheric Hg deposition. We conclude that the degree of photochemical processing of Hg is controlled by phytoplankton uptake rather than by dissolved organic carbon quantity among lakes.

  14. Psychosocial factors at work and the development of mobility limitations among adults in Denmark

    DEFF Research Database (Denmark)

    Hansen, Åse Marie; Darsø, Lilie; Manty, Minna

    2014-01-01

    Aim: Psychosocial factors in the working environment have been shown to be associated with mobility limitations, but this has not yet been confirmed in a Danish population. We aimed to examine how psychosocial factors at work are related to developing mobility limitations in Denmark. Methods......: This study is based on data from 2952 middle-aged men and women without mobility limitations in 2000. Results: We found increased risk of incident mobility limitations during 6-year follow up among men who often perceived high work pace (OR 5.45, 95% CI 1.21-24.52) vs. never, who only sometimes or....../never perceived the work to be meaningful (OR 6.54, 95% CI 1.55-27.55) vs. always, and who sometimes perceived high emotional demands at work (OR 7.85, 95% CI 1.78-34.65) vs. never. Among women, lower risk of incident mobility limitations was observed among those who in 2000 perceived high work pace sometimes (OR...

  15. Fuel channel life limiting factors that dictate fuel channel maintenance requirements

    International Nuclear Information System (INIS)

    Richinson, P.J.; Wong, H.W.; Ellis, P.J.

    1995-01-01

    CANDU reactors have been operating for 33 years. The Nuclear Power Demonstration (NPD) Unit started up in 1962 and the prototype of CANDU, Douglas Point, started in 1967. The first commercial reactors, Pickering Units 1 and 2 both went into service in 1971 closely followed by Units 3 and 4 in 1972 and 1973 respectively. Operating commercial reactor experience represents over 10,000 pressure tubes, not including the replaced channels in all the Pickering A Units, and nearly 130,000 pressure tube operating years. No pressure tube has yet operated for its 30 year design lifetime of 210 KEFPH at 80% capacity factor. The longest operating time for pressure tubes to-date is about 120 KEFPH in Pickering Unit 4. Many lessons have been learned regarding pressure tube life limiting factors from the early CANDU units and these, together with the information obtained from an extensive pressure tube R and D program, have resulted in many design changes and improvements in material properties, mainly from manufacturing route changes. Reactors built recently are expected to achieve their 30 year design life. The development of Periodic and In-service Inspection programs and equipment, assessment methodologies and acceptance criteria, and the development of maintenance tooling and procedures are enabling the life limiting factors to be addressed in the currently operating units. The life limiting factors in currently operating Units are reviewed in relation to the experience gained from the early units, the R and D programs and the inspection and maintenance performed to date. (author)

  16. Breastfeeding in the first hour of life and modern technology: prevalence and limiting factors

    Directory of Open Access Journals (Sweden)

    Maria Cristina Pillegi

    2008-12-01

    Full Text Available Objective: To identify the prevalence and limiting factors ofbreastfeeding in the first hour of life at the Maternity Center of HospitalIsraelita Albert Einstein, where the predominant model of childbirthcare is largely based on the use of modern technology. Methods: Aretrospective study with quantitative analysis in a middle and upperclass population of different cultural backgrounds. Data were obtainedfrom the delivery record book in a total of 12,350 births from January2004 to December 2007. Results: Of 12,350 births, 3,277 (26.9%were excluded because of contraindications to breastfeeding in thefirst hour of life such as: prematurity, respiratory distress, adverseeffects of anesthesia, obstetric conditions, congenital malformation,and others. Other 180 cases were excluded due to missing data.Of the remaining 8,893 cases, 2,279 (18.7% were not breastfedbecause of limiting factors that require improvement actions: highdelivery turnover, patient refusal, medical refusal, tiredness due toprolonged labor, loss of data recording. Cesarean delivery and the useof anesthesia did neither prevent breastfeeding in the first hour of lifenor skin-to-skin contact. The prevalence was 74.3%. Conclusions:The use of technology and the hospital practices interfere inbreastfeeding, but are not factors that prevent it. The identificationof the prevalence and limiting factors contributes to the evaluationof the care provided and elaboration of nursing interventions forcontinuous improvement of the care practice. Improvement actionsshould include prenatal care and delivery itself.

  17. Factors associated with dropout in a long term observational cohort of fishing communities around lake Victoria, Uganda.

    Science.gov (United States)

    Abaasa, Andrew; Asiki, Gershim; Mpendo, Juliet; Levin, Jonathan; Seeley, Janet; Nielsen, Leslie; Ssetaala, Ali; Nanvubya, Annet; De Bont, Jan; Kaleebu, Pontiano; Kamali, Anatoli

    2015-12-24

    Fishing communities are potentially suitable for Human immunodeficiency virus (HIV) efficacy trials due to their high risk profile. However, high mobility and attrition could decrease statistical power to detect the impact of a given intervention. We report dropout and associated factors in a fisher-folk observational cohort in Uganda. Human immunodeficiency virus-uninfected high-risk volunteers aged 13-49 years living in five fishing communities around Lake Victoria were enrolled and followed every 6 months for 18 months at clinics located within each community. Volunteers from two of the five communities had their follow-up periods extended to 30 months and were invited to attend clinics 10-40 km (km) away from their communities. Human immunodeficiency virus counseling and testing was provided, and data on sexual behaviour collected at all study visits. Study completion was defined as completion of 18 or 30 months or visits up to the date of sero-conversion and dropout as missing one or more visits. Discrete time survival models were fitted to find factors independently associated with dropout. A total of 1000 volunteers (55% men) were enrolled. Of these, 91.9% completed 6 months, 85.2% completed 12 months and 76.0% completed 18 months of follow-up. In the two communities with additional follow-up, 76.9% completed 30 months. In total 299 (29.9%) volunteers missed at least one visit (dropped out). Dropout was independently associated with age (volunteers aged 13-24 being most likely to dropout), gender [men being more likely to dropout than women [adjusted hazard ratio (aHR) 1.4; 95% confidence interval (CI) 1.1-1.8)], time spent in the fishing community (those who stayed dropout), History of marijuana use (users being more likely to dropout than non-users [1.7; (1.2-2.5)], ethnicity (non-Baganda being more likely to dropout than Baganda [1.5; (1.2-1.9)], dropout varied between the five fishing communities, having a new sexual partner in the previous 3 months [1

  18. Environmental impacts of genetic improvement of growth rate and feed conversion ratio in fish farming under rearing density and nitrogen output limitations

    NARCIS (Netherlands)

    Besson, M.; Aubin, J.; Komen, H.; Poelman, M.; Quillet, E.; Vandeputte, M.; Arendonk, Van J.A.M.; Boer, De I.J.M.

    2016-01-01

    Today, fish farming faces an increasing demand in fish products, but also various environmental challenges. Genetic improvement in growth rate and feed conversion ratio is known to be an efficient way to increase production and increase efficiency in fish farming. The environmental consequences

  19. Previous Exposure to the Fish Parasite Anisakis as a Potential Risk Factor for Gastric or Colon Adenocarcinoma.

    Science.gov (United States)

    Garcia-Perez, Juan Carlos; Rodríguez-Perez, Rosa; Ballestero, Araceli; Zuloaga, Jaime; Fernandez-Puntero, Belen; Arias-Díaz, Javier; Caballero, María Luisa

    2015-10-01

    Anisakiasis is a global disease caused by consumption of raw or lightly cooked fish contaminated with L3 Anisakis spp. larvae. High rates of parasitization of fish worldwide make Anisakis a serious health hazard. In fact, anisakiasis is a growing disease in countries such as Spain, Italy, and Japan, where consumption of raw/marinated fish is high. Some parasitic infections have been recognized as a causative factor for human cancer. Suggested mechanisms include chronic inflammation elicited by the parasite, and a possible tumorigenic effect from certain parasitic secretions. Anisakis can produce persistent local inflammation and granuloma, and larvae have been incidentally found in gastrointestinal (GI) tumors. Our aim was to discover possible differences in the prevalence of unnoticed or asymptomatic previous Anisakis infection in GI cancer patients compared with healthy individuals. Serum levels of specific antibodies against Anisakis antigens were used as a reliable marker of previous contact with their larvae. Ninety-four participants without a previous history of Anisakis infection were prospectively allocated into 1 of 2 groups: 47 patients with GI cancer and 47 controls. Specific IgE, IgA1, and IgG1 against the Anisakis recombinant antigens Ani s 1, Ani s 5, Ani s 9, and Ani s 10 were determined by an ELISA assay. The ratio of positivity to sIgA1, rAni s 1, or rAni s 5 was significantly higher in the cancer patients than in the controls (38.30% vs 6.38%, P cancer showed a higher proportion of positive results for sIgA1 to rAni s 1 (P cancer patients were shown to be positive for sIgA1 to both rAni s 1 (P cancer.

  20. Oceanographic Factors in Fishing Ground Location of Anchovy at Teluk Cenderawasih National Park, West Papua : Are These Factors Have an Effect of Whale Sharks Appearance Frequencies?

    Science.gov (United States)

    Nurul Ihsan, Evi; Yasmina Enita, Siti; Kunarso; Wirasatriya, Anindya

    2018-02-01

    The appearance frequencies of whale sharks in Teluk Cenderawasih National Park (TCNP) is unique because they appear throughout the year and are not related to any seasons. WWF Indonesia's monitoring results from 2011 untill now showed the appearance of whale sharks is closely related to the presence of fisherman liftnet and anchovies. This study focuses on oceanographic factors in fishing ground areas such as chlorophyll-a and satellite imagery data including chlorophyll-a, Sea surface Temperature (SST) over the last four years resulting in AQUA MODIS level 2 recording with 1km resolution in 2013-2016. The catch of anchovies and chlorophyll-a values showed a fairly good correlation during the west monsoon, 0.305, in addition the relationship between the anchovies with SST has a good correlation value starting in the transition period 1 towards the east monsoon. Based on these data, oceanographic factor conditions in TCNP provide a good opportunity for anchovies that live in warm waters to grow and reproduce. This also influences the appearance of whale sharks closely related to the presence of the anchovies where a positive correlation value is found between the catch of anchovies and whale sharks during the west monsoon and east monsoon in sequence 0,912 and 0.819. Chlorophyll-a and SST have a significant effect on fish catch of anchovies and the appearance frequencies of whale sharks even it were not in all seasons.

  1. Breastfeeding in the first hour of life and modern technology: prevalence and limiting factors

    OpenAIRE

    Maria Cristina Pillegi; Adriana Policastro; Sulim Abramovici; Eduardo Cordioli; Alice D’Agostini Deutsch

    2008-01-01

    Objective: To identify the prevalence and limiting factors ofbreastfeeding in the first hour of life at the Maternity Center of HospitalIsraelita Albert Einstein, where the predominant model of childbirthcare is largely based on the use of modern technology. Methods: Aretrospective study with quantitative analysis in a middle and upperclass population of different cultural backgrounds. Data were obtainedfrom the delivery record book in a total of 12,350 births from January2004 to December 200...

  2. Preliminary identification of the bioremediation limiting factors of a clay bearing soil contaminated with crude oil

    OpenAIRE

    Rizzo, Andréa C. L.; Cunha, Claudia D. da; Santos, Ronaldo L. C.; Santos, Renata M.; Magalhães, Hugo M.; Leite, Selma G. F.; Soriano, Adriana U.

    2008-01-01

    Bioremediation is an attractive alternative to treat soils contaminated with petroleum hydrocarbons. However, the effectiveness of biodegradation process can be limited by both contaminant characteristics and its bioavailability in soil. This work aims at establishing a preliminary procedure to identify the main factor (hydrocarbon recalcitrance or its bioavailability) that impairs the biodegradation, possibly resulting in low remediation efficiencies. Tests in soil microcosms were carried ou...

  3. Tokamak βaB/I limit and its dependence on the safety factor

    International Nuclear Information System (INIS)

    Ramos, J.J.

    1990-01-01

    It is shown that, for a given tokamak cross-sectional shape and arbitrary values of the magnetic axis safety factor q 0 , the first stability condition against pressure-driven magnetohydrodynamic modes has the form 40πβaB 0 /I≤C R (q 0 )/q 0 . Moreover, in the limit of large q 0 , C R (q 0 ) becomes independent of q 0 and independent of the toroidal mode number

  4. Biodiversities and limiting factors of Lashgardar Protected Area (LPA), Hamadan Province, Iran

    OpenAIRE

    MAHDI REYAHI KHORAM; VAHID NORISHARIKABAD

    2010-01-01

    Reyahi-Khoram M, Norisharikabad V (2011) Biodiversities and limiting factors of Lashgardar Protected Area (LPA), Hamadan Province, Iran. Biodiversitas 12: 216-221. Lashgardar Protected Area (LPA) located in Hamadan Province in Iran, it is a mountainous and plain area and proximal to Malayer Township. In 1991, the region was known as a protected area for increasing wild animals' population. This research has been conducted during 2001 through 2009. Plant and animal species of the region were i...

  5. Impact of selected risk factors on expected lifetime without long-standing, limiting illness in Denmark

    DEFF Research Database (Denmark)

    Brønnum-Hansen, Henrik; Juel, Knud; Davidsen, Michael

    2007-01-01

    long-standing, limiting illness was 8-10 years shorter among sedentary than physically active people. Obesity shortened lifetime without illness by 5 years for men and ten years for women. CONCLUSION: The results of this study could be used in health policy-making, as the potential gains in public......OBJECTIVE: To estimate the impacts of tobacco smoking, high alcohol consumption, physical inactivity and overweight on expected lifetime with and without long-standing, limiting illness. METHODS: Life tables for each level of exposure to the risk factors were constructed, mainly on the basis......-olds was 9-10 years shorter for heavy smokers than for those who never smoke, and all the lifetime lost would have been without long-standing, limiting illness. Similarly, all 5 years of expected lifetime lost by men with high alcohol consumption would have been without illness. The expected lifetime without...

  6. Turbine related fish mortality

    International Nuclear Information System (INIS)

    Eicher, G.J.

    1993-01-01

    A literature review was conducted to assess the factors affecting turbine-related fish mortality. The mechanics of fish passage through a turbine is outlined, and various turbine related stresses are described, including pressure and shear effects, hydraulic head, turbine efficiency, and tailwater level. The methodologies used in determining the effects of fish passage are evaluated. The necessity of adequate controls in each test is noted. It is concluded that mortality is the result of several factors such as hardiness of study fish, fish size, concentrations of dissolved gases, and amounts of cavitation. Comparisons between Francis and Kaplan turbines indicate little difference in percent mortality. 27 refs., 5 figs

  7. What is the most prominent factor limiting photosynthesis in different layers of a greenhouse cucumber canopy?

    Science.gov (United States)

    Chen, Tsu-Wei; Henke, Michael; de Visser, Pieter H B; Buck-Sorlin, Gerhard; Wiechers, Dirk; Kahlen, Katrin; Stützel, Hartmut

    2014-09-01

    Maximizing photosynthesis at the canopy level is important for enhancing crop yield, and this requires insights into the limiting factors of photosynthesis. Using greenhouse cucumber (Cucumis sativus) as an example, this study provides a novel approach to quantify different components of photosynthetic limitations at the leaf level and to upscale these limitations to different canopy layers and the whole plant. A static virtual three-dimensional canopy structure was constructed using digitized plant data in GroIMP. Light interception of the leaves was simulated by a ray-tracer and used to compute leaf photosynthesis. Different components of photosynthetic limitations, namely stomatal (S(L)), mesophyll (M(L)), biochemical (B(L)) and light (L(L)) limitations, were calculated by a quantitative limitation analysis of photosynthesis under different light regimes. In the virtual cucumber canopy, B(L) and L(L) were the most prominent factors limiting whole-plant photosynthesis. Diffusional limitations (S(L) + M(L)) contributed Photosynthesis in the lower canopy was more limited by the biochemical capacity, and the upper canopy was more sensitive to light than other canopy parts. Although leaves in the upper canopy received more light, their photosynthesis was more light restricted than in the leaves of the lower canopy, especially when the light condition above the canopy was poor. An increase in whole-plant photosynthesis under diffuse light did not result from an improvement of light use efficiency but from an increase in light interception. Diffuse light increased the photosynthesis of leaves that were directly shaded by other leaves in the canopy by up to 55%. Based on the results, maintaining biochemical capacity of the middle-lower canopy and increasing the leaf area of the upper canopy would be promising strategies to improve canopy photosynthesis in a high-wire cucumber cropping system. Further analyses using the approach described in this study can be expected to

  8. Self-imposed length limits in recreational fisheries

    Science.gov (United States)

    Chizinski, Christopher J.; Martin, Dustin R.; Hurley, Keith L.; Pope, Kevin L.

    2014-01-01

    A primary motivating factor on the decision to harvest a fish among consumptive-orientated anglers is the size of the fish. There is likely a cost-benefit trade-off for harvest of individual fish that is size and species dependent, which should produce a logistic-type response of fish fate (release or harvest) as a function of fish size and species. We define the self-imposed length limit as the length at which a captured fish had a 50% probability of being harvested, which was selected because it marks the length of the fish where the probability of harvest becomes greater than the probability of release. We assessed the influences of fish size, catch per unit effort, size distribution of caught fish, and creel limit on the self-imposed length limits for bluegill Lepomis macrochirus, channel catfish Ictalurus punctatus, black crappie Pomoxis nigromaculatus and white crappie Pomoxis annularis combined, white bass Morone chrysops, and yellow perch Perca flavescens at six lakes in Nebraska, USA. As we predicted, the probability of harvest increased with increasing size for all species harvested, which supported the concept of a size-dependent trade-off in costs and benefits of harvesting individual fish. It was also clear that probability of harvest was not simply defined by fish length, but rather was likely influenced to various degrees by interactions between species, catch rate, size distribution, creel-limit regulation and fish size. A greater understanding of harvest decisions within the context of perceived likelihood that a creel limit will be realized by a given angler party, which is a function of fish availability, harvest regulation and angler skill and orientation, is needed to predict the influence that anglers have on fish communities and to allow managers to sustainable manage exploited fish populations in recreational fisheries.

  9. [Limiting factors in the class III camouflage treatment: a potential protocol].

    Science.gov (United States)

    Chaques Asensi, José

    2016-06-01

    The Class III skeletal malocclusion has been traditionally treated with a combined approach of orthodontics and orthognathic surgery or with a strategy of orthodontic camouflage. Some severe cases can be identified as ideal candidates for a surgical treatment whereas some others can be handled with orthodontics alone, with a reasonable expectation of an acceptable result. However, the problem remains for the borderline patient. In fact, limited information is available in the literature regarding the identification of the factors that can help in establishing the limits for one treatment modality or the other. Furthermore, the quantification of some of these factors, for practical purposes, is practically missing or very seldom suggested. Therefore, the decision making process remains a subjective reflection based on the "good clinical sense" of the orthodontist or just reduced to an "educated guess". In order to add some information, hopefully useful in deciding the most suitable treatment option for the individual patient, we propose a clinical protocol based on four different factors. Namely: the skeletal discrepancy, the occlusal discrepancy, the periodontal condition and facial aesthetics. For each one of these factors several parameters will be evaluated and, for some of them, an attempt to provide some reference numerical values will be made. Finally, clinical examples will be presented to illustrate the concepts discussed and the treatment alternatives, final treatment plan and treatment outcome will be analyzed for each one of them. © EDP Sciences, SFODF, 2016.

  10. Thermodynamic limit of particle-hole form factors in the massless XXZ Heisenberg chain

    Energy Technology Data Exchange (ETDEWEB)

    Kitanine, N. [Univ. de Bourgogne (France). IMB, UMR 5584 du CNRS; Kozlowski, K.K. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Maillet, J.M.; Terras, V. [ENS Lyon (France). UMR 5672 du CNRS, Lab. de Physique; Slavnov, N.A. [Steklov Mathematical Inst., Moscow (Russian Federation)

    2011-03-15

    We study the thermodynamic limit of the particle-hole form factors of the XXZ Heisenberg chain in the massless regime. We show that, in this limit, such form factors decrease as an explicitly computed power-law in the system size. Moreover, the corresponding amplitudes can be obtained as a product of a ''smooth'' and a ''discrete'' part: the former depends continuously on the rapidities of the particles and holes, whereas the latter has an additional explicit dependence on the set of integer numbers that label each excited state in the associated logarithmic Bethe equations. We also show that special form factors corresponding to zero-energy excitations lying on the Fermi surface decrease as a power-law in the system size with the same critical exponents as in the longdistance asymptotic behavior of the related two-point correlation functions. The methods we develop in this article are rather general and can be applied to other massless integrable models associated to the six-vertex R-matrix and having determinant representations for their form factors. (orig.)

  11. Registration factors that limit international mobility of people holding physiotherapy qualifications: A systematic review.

    Science.gov (United States)

    Foo, Jonathan S; Storr, Michael; Maloney, Stephen

    2016-06-01

    There is no enforced international standardisation of the physiotherapy profession. Thus, registration is used in many countries to maintain standards of care and to protect the public. However, registration may also limit international workforce mobility. What is known about the professional registration factors that may limit the international mobility of people holding physiotherapy qualifications? Systematic review using an electronic database search and hand searching of the World Confederation for Physical Therapy and International Network of Physiotherapy Regulatory Authorities websites. Analysis was conducted using thematic analysis. 10 articles and eight websites were included from the search strategy. Data is representative of high-income English speaking countries. Four themes emerged regarding limitations to professional mobility: practice context, qualification recognition, verification of fitness to practice, and incidental limitations arising from the registration process. Professional mobility is limited by differences in physiotherapy education programmes, resulting in varying standards of competency. Thus, it is often necessary to verify clinical competencies through assessments, as well as determining professional attributes and ability to apply competencies in a different practice context, as part of the registration process. There has been little evaluation of registration practices, and at present, there is a need to re-evaluate current registration processes to ensure they are efficient and effective, thereby enhancing workforce mobility. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Comparing the demographic factors of patient with limited and diffuse type of alopecia areata

    Directory of Open Access Journals (Sweden)

    Mina Daliri

    2010-09-01

    Full Text Available Background: Alopecia areata is a chronic inflammatory disease that involves the hair follicle. Clinically, patients with alopecia areata may have patchy or confluent hair loss on the scalp or body so we conduct a study to compare the demographic aspects of patient with limited and diffuse type of alopecia areata.Materials and Method: We conducted a descriptive-analyzing study in which 306 patient were chosen. The patients were divided into two groups of diffuse and limited Alopecia. Demographic factors including age, gender, disease onset were compared in two groups. Results: Out of 306 patients, 58.8 % were male and 41.2 % were female. 247 patients (80.7% suffered from limited type and 59 patients (19.2% suffered from diffuse type. The mean age of the onset of involvement in limited group was 21.9±12 yr and 15.8±12 yr in diffuse group. The mean duration of involvement in limited group was 18.7 months and 71 months in diffuse group. Conclusion: Diffuse type alopecia areata starts at lower age and has longer duration. Our study results were similar to the others. Like other studies, thyroid disorders and atopic dermatitis are positively correlative to the severity of disease

  13. Using thermal limits to assess establishment of fish dispersing to high-latitude and high-elevation watersheds

    Science.gov (United States)

    Dunmall, Karen M.; Mochnacz, Neil J.; Zimmerman, Christian E.; Lean, Charles; Reist, James D.

    2016-01-01

    Distributional shifts of biota to higher latitudes and elevations are presumably influenced by species-specific physiological tolerances related to warming temperatures. However, it is establishment rather than dispersal that may be limiting colonizations in these cold frontier areas. In freshwater ecosystems, perennial groundwater springs provide critical winter thermal refugia in these extreme environments. By reconciling the thermal characteristics of these refugia with the minimum thermal tolerances of life stages critical for establishment, we develop a strategy to focus broad projections of northward and upward range shifts to the specific habitats that are likely for establishments. We evaluate this strategy using chum salmon (Oncorhynchus keta) and pink salmon (Oncorhynchus gorbuscha) that seem poised to colonize Arctic watersheds. Stream habitats with a minimum temperature of 4 °C during spawning and temperatures above 2 °C during egg incubation were most vulnerable to establishments by chum and pink salmon. This strategy will improve modelling forecasts of range shifts for cold freshwater habitats and focus proactive efforts to conserve both newly emerging fisheries and native species at northern and upper distributional extremes.

  14. Factors Limiting Adoption of Technologies by Farmers in Catabola Municipality, Angola

    Directory of Open Access Journals (Sweden)

    Rušarová K.

    2016-06-01

    Full Text Available The objective of the paper is to define the factors influencing the adoption of animal traction and/or mechanical-power technology in the conditions of Catabola municipality where hand-tool technology is being used on 99.7% of the area cultivated by small farmers. Primary data collection was conducted in the period July–August 2011; semi-structured questionnaires and focus group discussions were the most frequent methods used. In total, 151 small-scale farmers from 9 villages participated in the survey. Ten factors influencing the dependent variable – level of technology used by farmers in combination with hiring of labour – were defined. The factors were statistically analyzed by ANOVA. The area of cultivated land and the educational level of both parents and children were found to be the factors limiting the process of animal traction or mechanical power adoption by small farmers in the Catabola municipality. In addition, a relatively high rate of child labour was observed. With the exclusion of childless families, 62.7% of small farmer families regularly use children aged 0–14 years for field operations. The results confirm that the factor of hiring extra labour is irrelevant in determining the development in technology use by small farmers in the Catabola municipality.

  15. Interleukin-17 limits hypoxia-inducible factor 1α and development of hypoxic granulomas during tuberculosis.

    Science.gov (United States)

    Domingo-Gonzalez, Racquel; Das, Shibali; Griffiths, Kristin L; Ahmed, Mushtaq; Bambouskova, Monika; Gopal, Radha; Gondi, Suhas; Muñoz-Torrico, Marcela; Salazar-Lezama, Miguel A; Cruz-Lagunas, Alfredo; Jiménez-Álvarez, Luis; Ramirez-Martinez, Gustavo; Espinosa-Soto, Ramón; Sultana, Tamanna; Lyons-Weiler, James; Reinhart, Todd A; Arcos, Jesus; de la Luz Garcia-Hernandez, Maria; Mastrangelo, Michael A; Al-Hammadi, Noor; Townsend, Reid; Balada-Llasat, Joan-Miquel; Torrelles, Jordi B; Kaplan, Gilla; Horne, William; Kolls, Jay K; Artyomov, Maxim N; Rangel-Moreno, Javier; Zúñiga, Joaquín; Khader, Shabaana A

    2017-10-05

    Mycobacterium tuberculosis (Mtb) is a global health threat, compounded by the emergence of drug-resistant strains. A hallmark of pulmonary tuberculosis (TB) is the formation of hypoxic necrotic granulomas, which upon disintegration, release infectious Mtb. Furthermore, hypoxic necrotic granulomas are associated with increased disease severity and provide a niche for drug-resistant Mtb. However, the host immune responses that promote the development of hypoxic TB granulomas are not well described. Using a necrotic Mtb mouse model, we show that loss of Mtb virulence factors, such as phenolic glycolipids, decreases the production of the proinflammatory cytokine IL-17 (also referred to as IL-17A). IL-17 production negatively regulates the development of hypoxic TB granulomas by limiting the expression of the transcription factor hypoxia-inducible factor 1α (HIF1α). In human TB patients, HIF1α mRNA expression is increased. Through genotyping and association analyses in human samples, we identified a link between the single nucleotide polymorphism rs2275913 in the IL-17 promoter (-197G/G), which is associated with decreased IL-17 production upon stimulation with Mtb cell wall. Together, our data highlight a potentially novel role for IL-17 in limiting the development of hypoxic necrotic granulomas and reducing disease severity in TB.

  16. Effects of Common Factors on Dynamics of Stocks Traded by Investors with Limited Information Capacity

    Directory of Open Access Journals (Sweden)

    Songtao Wu

    2017-01-01

    Full Text Available An artificial stock market with agent-based model is built to investigate effects of different information characteristics of common factors on the dynamics stock returns. Investors with limited information capacity update their beliefs based on the information they have obtained and processed and optimize portfolios based on beliefs. We find that with changing of concerned information characteristics the uncertainty of stock price returns rises and is higher than the uncertainty of intrinsic value returns. However, this increase is constrained by the limited information capacity of investors. At the same time, we also find that dependence between returns of stock prices also increased with the changing information environment. The uncertainty and dependency pertaining to prices show a positive relationship. However, the positive relationship is weakened when taking into account the features of intrinsic values, based on which prices are generated.

  17. Unlocking Ft: Modeling thermodynamic controls and isotope fractionation factors in nutrient limited environments

    Science.gov (United States)

    Druhan, J. L.; Giannetta, M.; Sanford, R. A.

    2017-12-01

    In recent years, reactive transport principles have expanded from early applications, largely based in contaminant hydrology, to a wide range of biologically mediated redox environments including marine sedimentary diagenesis, terrestrial metal ore deposits, soils, and critical zone weathering profiles. A common observation across this diversity of systems is that they often function under energetically limited conditions in comparison to those typical of contaminated aquifers subject to engineered remediation techniques. As a result, the kinetic rate expressions traditionally employed within reactive transport frameworks to simulate microbially mediated redox transformations have required modification. This was recognized in a series of seminal papers by Jin and Bethke (2005, 2007) in which the authors expanded upon a Monod rate law to include a thermodynamic potential factor `Ft' which exerts a limitation on the overall rate based on the thermodynamic driving force of the electron transfer reaction. This new rate expression is now commonly implemented within many of the major reactive transport software packages, though appropriate application has yet to be thoroughly demonstrated. Notably, the characteristically large partitioning of stable isotopes during microbially mediated reactions, which is extensively utilized to identify and quantify these redox transformations, has yet to be simulated under conditions in which the Ft term may be expected to exert a significant mass dependent influence. Here, we develop a series of simplified simulations for the microbially mediated reduction of sulfate based on the datasets reported by Jin and Bethke, and apply appropriate mass-bias within the Ft term to consider the extent to which the resulting isotopic fractionation is consistent with that observed in energetically limited systems. We show that the Ft term can exert a significant influence on the observed fractionation factor under common environmental conditions

  18. Density as a factor limiting the workability of P/M materials

    International Nuclear Information System (INIS)

    Libura, W.; Zasadzinski, J.

    1993-01-01

    In this study a general scheme expressing the factors which affect a workability of powder materials is presented. It was found from laboratory experiments that workability of powder metal materials is limited by their density. Aluminium based materials with additions of Cu, Ni and Sn were used in the experiments. Workability determined in compression tests depends strongly on a sintered density, independently of the chemical composition of material. A linear dependence between workability and sintered density was found. The results are related to relatively high density values, taken from the range of 0.85-0.96 of theoretical density. (orig.)

  19. Sensory shelf-life limiting factor of high hydrostatic pressure processed avocado paste.

    Science.gov (United States)

    Jacobo-Velázquez, D A; Hernández-Brenes, C

    2011-08-01

    High hydrostatic pressure (HHP) processing pasteurizes avocado paste without a significant impact on flavor. Although HHP-treated avocado paste stored under refrigeration is safe for human consumption for months, sensory changes taking place during storage cause the rejection of the product by consumers within days. Although it is known that the shelf life of the product ends before its microbial counts are high, its sensory shelf life limiting factor remains unknown. The present study focused on the use of a trained panel and a consumer panel to determine the sensory shelf life limiting factor of HHP-treated avocado paste. The trained panel identified sour and rancid flavors as the main sensory descriptors (critical descriptors) that differentiated stored from freshly processed samples. Further data obtained from consumers identified sour flavor as the main cause for a significant decrease in the acceptability (shelf life limiting factor) of refrigerated HHP-treated avocado paste. The study allowed the elucidation of a proposed deterioration mechanism for HHP-treated avocado paste during its refrigerated shelf life. The information through this work enhances scientific knowledge of the product and proposes the sour flavor development during storage as a relevant sensory attribute that needs to be improved in order to enhance the product shelf life. At present, HHP is the most effective commercial nonthermal technology to process avocado paste when compared to thermal and chemical alternatives. HHP-treated avocado paste is a microbiologically stable food for a period of at least 45 d stored under refrigeration. However, previous published work indicated that consumers rejected the product after approximately 19 d of storage due to sensory changes. This manuscript presents a sensory study that permitted the identification of the critical sensory descriptor that is acting as the sensory shelf life limiting factor of the product. The data presented herein along with

  20. Limiting factors for vegetation development during the early late glacial in Denmark

    DEFF Research Database (Denmark)

    Mortensen, Morten Fischer; Odgaard, Bent Vad; Jessen, Cathrine

    Slotseng, a small basin in southern Jutland, is the first Danish site with a bio- and chronostratigraphy that unambiguously reflects the environment of the earliest late glacial, the Bølling period. Results of pollen and macrofossil analyses show that the vegetation of the Bølling and Older Dryas...... periods at Slotseng was dominated by Betula nana and Dryas octopetala and associated with many herbs of open habitats. Late-glacial pollen records are frequently interpreted only in the context of climate change. However, the forcing mechanisms of vegetational change may shift over time between e...... to climate change suggests that other factors limited vegetational development. These factors included soil instability, aridity and low soil nitrogen.. This study highlights the multitude of climatic, physical, chemical and biological interactions important for the formation of pollen records of late...

  1. Fish Oil and Microalga Omega-3 as Dietary Supplements: A Comparative Study on Cardiovascular Risk Factors in High-Fat Fed Rats.

    Science.gov (United States)

    Haimeur, Adil; Mimouni, Virginie; Ulmann, Lionel; Martineau, Anne-Sophie; Messaouri, Hafida; Pineau-Vincent, Fabienne; Tremblin, Gérard; Meskini, Nadia

    2016-09-01

    Dietary supplementation with marine omega-3 polyunsaturated fatty acids (n-3 PUFA) can have beneficial effects on a number of risk factors for cardiovascular disease (CVD). We compared the effects of two n-3 PUFA rich food supplements (freeze-dried Odontella aurita and fish oil) on risk factors for CVD. Male rats were randomly divided into four groups of six animals each and fed with the following diets: control group (C) received a standard diet containing 7 % lipids; second group (HF high fat) was fed with a high-fat diet containing 40 % lipids; third group (HFFO high fat+fish oil) was fed with the high-fat diet supplemented with 0.5 % fish oil; and fourth group (HFOA high fat+O. aurita) received the high-fat diet supplemented with 12 % of freeze-dried O. aurita. After 8 weeks rats fed with the high-fat diet supplemented with O. aurita displayed a significantly lower bodyweight than those in the other groups. Both the microalga and the fish oil significantly reduced insulinemia and serum lipid levels. O. aurita was more effective than the fish oil in reducing hepatic triacyglycerol levels and in preventing high-fat diet-induced steatosis. O. aurita and fish oil also reduced platelet aggregation and oxidative status induced by high fat intake. After an OA supplementation, the adipocytes in the HFOA group were smaller than those in the HF group. Freeze-dried O. aurita showed similar or even greater biological effects than the fish oil. This could be explained by a potential effect of the n-3 PUFA but also other bioactive compounds of the microalgae.

  2. Factors limiting deceased organ donation: focus groups' perspective from culturally diverse community.

    Science.gov (United States)

    Wong, L P

    2010-06-01

    In-depth understanding of cultural and religious factors limiting organ donation of three ethnic populations (Malay, Chinese, and Indian) in Southeast Asia is lacking. Identification of factors limiting organ donation among these three ethnic groups will provide insights into culturally appropriate strategies to promote acceptance of organ donation in a multiethnic Asian community. A total of 17 focus group discussions (105 participants) were conducted between September and December 2008. Participants were members of the general public aged 18 to 60 years, recruited through convenient sampling around the Klang Valley area of Malaysia. Although the majority had favorable attitudes toward deceased organ donation and transplantation, a diversity of myths and misinformation were unearthed from the discussions across the ethnic groups. These include perceived religious prohibition, cultural myths and misperceptions, fear of disfigurement, fear of surgery, distrust of the medical system, and family disapproval. Culture and religious beliefs played important prohibitive roles among those opposed to organ donations. There were distinctive ethnic differences in cultural and religious concerns regarding organ donation. Less-educated and rural groups appeared to have more misconceptions than the well-educated and the urban groups. Our findings may assist organ donation and transplantation organizations to reach diverse sociodemographic and ethnic communities with culture-specific information about organ donation. The involvement of community and religious leaders is critical in organ donation requests.

  3. Farmer perceptions on factors influencing water scarcity for goats in resource-limited communal farming environments.

    Science.gov (United States)

    Mdletshe, Zwelethu Mfanafuthi; Ndlela, Sithembile Zenith; Nsahlai, Ignatius Verla; Chimonyo, Michael

    2018-05-09

    The objective of the study was to compare factors influencing water scarcity for goats in areas where there are seasonal and perennial rivers under resource-limited communal farming environments. Data were collected using a structured questionnaire (n = 285) administered randomly to smallholder goat farmers from areas with seasonal and perennial rivers. Ceremonies was ranked as the major reason for keeping goats. Water scarcity was ranked the major constraint to goat production in areas with seasonal rivers when compared to areas with perennial rivers (P goat drinking in areas with seasonal and perennial river systems during cool dry and rainy seasons. Rivers were ranked as an important water source for goat drinking where there are seasonal and perennial river systems during the cool dry season. Households located close (≤ 3 km) to the nearest water source reported drinking water for goats a scarce resource. These results show that river systems, season and distance to the nearest water source from a household were factors perceived by farmers to influence water scarcity for goats in resource-limited communal farming environments. Farmers should explore water-saving strategies such as recycling wastewater from kitchens and bathrooms as an alternative water source. The government may assist farmers through sinking boreholes to supply water for both humans and livestock.

  4. Economic values of growth and feed efficiency for fish farming in recirculating aquaculture system with density and nitrogen output limitations: a case study with African catfish (Clarias gariepinus)

    NARCIS (Netherlands)

    Besson, M.; Komen, H.; Aubin, J.; Boer, de I.J.M.; Poelman, M.; Quillet, E.; Vancoillie, C.; Vandeputte, M.; Arendonk, van J.A.M.

    2014-01-01

    In fish farming, economic values (EV) of breeding goal traits are lacking, even though they are key parameters when defining selection objectives. The aim of this study was to develop a bioeconomic model to estimate EV of 2 traits representing production performances in fish farming: the thermal

  5. Factors affecting the abundance of selected fishes near oil and gas platforms in the northern Gulf of Mexico

    International Nuclear Information System (INIS)

    Stanley, D.R.; Wilson, C.A.

    1991-01-01

    A logbook program was initiated to determine the relative abundance of selected fish species around oil and gas platforms off the Louisiana coast. Logbooks were maintained by 55 anglers and 10 charterboat operators from March 1987 to March 1988. A total of 36,839 fish were caught representing over 46 different species. Principal component analysis (PCA) grouped the seventeen most abundant species into reef fish, pelagic fish, bluefish-red drum, Atlantic croaker-silver/sand seatrout, and cobia-shark-blue runner associations. Multiple regression analyses were used to compare PCA groupings to physical platform, temporal, geological, and angler characteristic variables and their interactions. Reef fish, Atlantic croaker, and silver/sand seatrout abundances were highest near large, structurally complex platforms in relatively deep water. High spotted seatrout abundances were correlated with small, unmanned oil and gas platforms in shallow water. Pelagic fish, bluefish, red drum, cobia, and shark abundances were not related to the physical parameters of the platforms

  6. Factors affecting the abundance of selected fishes near oil and gas platforms in the northern Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Stanley, D.R.; Wilson, C.A. (Louisiana State Univ., Baton Rouge (United States))

    1991-01-01

    A logbook program was initiated to determine the relative abundance of selected fish species around oil and gas platforms off the Louisiana coast. Logbooks were maintained by 55 anglers and 10 charterboat operators from March 1987 to March 1988. A total of 36,839 fish were caught representing over 46 different species. Principal component analysis (PCA) grouped the seventeen most abundant species into reef fish, pelagic fish, bluefish-red drum, Atlantic croaker-silver/sand seatrout, and cobia-shark-blue runner associations. Multiple regression analyses were used to compare PCA groupings to physical platform, temporal, geological, and angler characteristic variables and their interactions. Reef fish, Atlantic croaker, and silver/sand seatrout abundances were highest near large, structurally complex platforms in relatively deep water. High spotted seatrout abundances were correlated with small, unmanned oil and gas platforms in shallow water. Pelagic fish, bluefish, red drum, cobia, and shark abundances were not related to the physical parameters of the platforms.

  7. 23 CFR 636.302 - Are there any limitations on the selection and use of proposal evaluation factors?

    Science.gov (United States)

    2010-04-01

    ... Are there any limitations on the selection and use of proposal evaluation factors? (a) The selection... 23 Highways 1 2010-04-01 2010-04-01 false Are there any limitations on the selection and use of proposal evaluation factors? 636.302 Section 636.302 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF...

  8. Impact of fish consumption by subjects with prediabetes on the metabolic risk factors: using data in the 2015 (6th) Korea National Health and Nutrition Examination Surveys.

    Science.gov (United States)

    Kim, Kyoung-Yun; Park, Jeong Seop

    2018-06-01

    The effects of fish consumption by subjects with prediabetes on the metabolic risk factors were examined based on the data from the 6 th Korea National Health and Nutrition Examination Surveys in 2015. A total of 1,520 subjects who agreed to participate in a blood test and dietary intake survey were divided into a prediabetes group and normal blood glucose group, and the level of the subjects' fish consumption was divided into ≤ 17.0 g/day, 18.0-93.0 g/day, and ≥ 94 g/day. The correlation between the level of fish intake and the metabolic risk factors was evaluated by multinomial logistic regression analysis. A significant difference in the gender distribution was observed in the prediabetes group, which is a group with a high risk of non-communicable diseases, according to the fish intake, and there were significant differences in the total energy intake, protein intake, n-3 fatty acids intake, and the intakes of sodium and micro-nutrients according to the intake group ( P < 0.05). In addition, the blood total cholesterol (TC) decreased 0.422 fold in model 1 (unadjusted) [95% confidence interval (CI): 0.211-0.845] and 0.422 fold in model 2 (adjusted for sex) (95% CI: 0.210-0.846) in those with a fish intake of 18.0-93.0 g/day ( P < 0.05) compared to those with a fish intake of ≤ 17.0 g/day. The blood TC decreased 0.555 fold (95% CI: 0.311-0.989) in model 1 and 0.549 fold (95% CI: 0.302-0.997) in model 2 in those with a fish intake of ≥ 94 g/day compared to those with a fish intake of ≤ 17.0 g/day ( P < 0.05). Subjects with prediabetes or the metabolic risk factors can maintain their blood low density lipoprotein cholesterol (LDL-C) and blood TC concentrations at the optimal level by consuming fish (18.0-93.0 g/day).

  9. Trait Mindfulness as a Limiting Factor for Residual Depressive Symptoms: An Explorative Study Using Quantile Regression

    Science.gov (United States)

    Radford, Sholto; Eames, Catrin; Brennan, Kate; Lambert, Gwladys; Crane, Catherine; Williams, J. Mark G.; Duggan, Danielle S.; Barnhofer, Thorsten

    2014-01-01

    Mindfulness has been suggested to be an important protective factor for emotional health. However, this effect might vary with regard to context. This study applied a novel statistical approach, quantile regression, in order to investigate the relation between trait mindfulness and residual depressive symptoms in individuals with a history of recurrent depression, while taking into account symptom severity and number of episodes as contextual factors. Rather than fitting to a single indicator of central tendency, quantile regression allows exploration of relations across the entire range of the response variable. Analysis of self-report data from 274 participants with a history of three or more previous episodes of depression showed that relatively higher levels of mindfulness were associated with relatively lower levels of residual depressive symptoms. This relationship was most pronounced near the upper end of the response distribution and moderated by the number of previous episodes of depression at the higher quantiles. The findings suggest that with lower levels of mindfulness, residual symptoms are less constrained and more likely to be influenced by other factors. Further, the limiting effect of mindfulness on residual symptoms is most salient in those with higher numbers of episodes. PMID:24988072

  10. Prognostic factors for patients with inoperable non-small cell lung cancer, limited disease

    International Nuclear Information System (INIS)

    Kaasa, S.; Mastekaasa, A.; Lund, E.

    1989-01-01

    In a prospective controlled clinical trial, 102 patients with inoperable non-small lung cancer (NSCLC), limited disease, stage II and III were treated with combination chemotherapy, cisplatin 70 mg/m 2 i.v. on day one and etoposide 100 mg/m 2 i.v. on day one, and etoposide 200 mg/m 2 orally on days 2 and 3, or radiotherapy given in 15 fractions of 2.8 Gy with two anterior/posterior fields during a period of three weeks. The patients completed a validated self-administered questionnaire before the start of treatment that assessed their psychosocial well-being, disease-related symptoms, personal functioning, and every day activity. These subjective varibles were evaluated together with treatment modality, WHO performance status, weight loss, and stage of disease, with regard to their value in predicting survival. Univariate survival analyses were undertaken for each individual factor, median survival was calculated according to life-table analyses. A step-wise multiple regression analysis was used to measure the prognostic value of the various factors. In the univariate analysis, general symptons (p=0.0006) psychosocial well-being (p=0.0002) and stage of disease (p=0.007) were the best predictive factors. In the multiple regression analyses the subjective variables, general symptons (p<0.01) and psychosocial well-being (p<0.05) were shown to have the best predictive value for the patients' survival. (author). 20 refs.; 4 figs.; 3 tabs

  11. Searching out the hydrogen absorption/desorption limiting reaction factors: Strategies allowing to increase kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Zeaiter, Ali, E-mail: ali.zeaiter@femto-st.fr; Chapelle, David; Nardin, Philippe

    2015-10-05

    Highlights: • A macro scale thermodynamic model that simulates the response of a FeTi-X hydride tank is performed, and validated experimentally. • A sensibility study to identify the most influent input variables that can changes very largely the reaction rate. - Abstract: Hydrogen gas has become one of the most promising energy carriers. Main breakthrough concerns hydrogen solid storage, specially based on intermetallic material use. Regarding the raw material abundance and cost, the AB type alloy FeTi is an auspicious candidate to store hydrogen. Its absorption/desorption kinetics is a basic hindrance to common use, compared with more usual hydrides. First, discussions based on literature help us identifying the successive steps leading to metal hydriding, and allow to introduce the physical parameters which drive or limit the reaction. This analysis leads us to suggest strategies in order to increase absorption/desorption kinetics. Attention is then paid to a thermofluidodynamic model, allowing to describe a macroscopic solid storage reactor. Thus, we can achieve a simulation which describes the overall reaction inside the hydrogen reactor and, by varying the sub-mentioned parameters (thermal conductivity, the powder granularity, environment heat exchange…), we attempt to hierarchy the reaction limiting factors. These simulations are correlated to absorption/desorption experiments for which pressure, temperature and hydrogen flow are recorded.

  12. Linear and nonlinear models for predicting fish bioconcentration factors for pesticides.

    Science.gov (United States)

    Yuan, Jintao; Xie, Chun; Zhang, Ting; Sun, Jinfang; Yuan, Xuejie; Yu, Shuling; Zhang, Yingbiao; Cao, Yunyuan; Yu, Xingchen; Yang, Xuan; Yao, Wu

    2016-08-01

    This work is devoted to the applications of the multiple linear regression (MLR), multilayer perceptron neural network (MLP NN) and projection pursuit regression (PPR) to quantitative structure-property relationship analysis of bioconcentration factors (BCFs) of pesticides tested on Bluegill (Lepomis macrochirus). Molecular descriptors of a total of 107 pesticides were calculated with the DRAGON Software and selected by inverse enhanced replacement method. Based on the selected DRAGON descriptors, a linear model was built by MLR, nonlinear models were developed using MLP NN and PPR. The robustness of the obtained models was assessed by cross-validation and external validation using test set. Outliers were also examined and deleted to improve predictive power. Comparative results revealed that PPR achieved the most accurate predictions. This study offers useful models and information for BCF prediction, risk assessment, and pesticide formulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Evaluation of Limiting Climatic Factors and Simulation of a Climatically Suitable Habitat for Chinese Sea Buckthorn.

    Directory of Open Access Journals (Sweden)

    Guoqing Li

    Full Text Available Chinese sea buckthorn (Hippophae rhamnoides subsp. sinensis has considerable economic potential and plays an important role in reclamation and soil and water conservation. For scientific cultivation of this species across China, we identified the key climatic factors and explored climatically suitable habitat in order to maximize survival of Chinese sea buckthorn using MaxEnt and GIS tools, based on 98 occurrence records from herbarium and publications and 13 climatic factors from Bioclim, Holdridge life zone and Kria' index variables. Our simulation showed that the MaxEnt model performance was significantly better than random, with an average test AUC value of 0.93 with 10-fold cross validation. A jackknife test and the regularized gain change, which were applied to the training algorithm, showed that precipitation of the driest month (PDM, annual precipitation (AP, coldness index (CI and annual range of temperature (ART were the most influential climatic factors in limiting the distribution of Chinese sea buckthorn, which explained 70.1% of the variation. The predicted map showed that the core of climatically suitable habitat was distributed from the southwest to northwest of Gansu, Ningxia, Shaanxi and Shanxi provinces, where the most influential climate variables were PDM of 1.0-7.0 mm, AP of 344.0-1089.0 mm, CI of -47.7-0.0°C, and ART of 26.1-45.0°C. We conclude that the distribution patterns of Chinese sea buckthorn are related to the northwest winter monsoon, the southwest summer monsoon and the southeast summer monsoon systems in China.

  14. Limiting Factors for Agricultural Production and Differentiation of Soil Management in Romania

    Science.gov (United States)

    Ioana Moraru, Paula; Rusu, Teodor; Bogdan, Ileana; Ioan Pop, Adrian; Pop, Horia

    2017-04-01

    Romania's land area is 23,839,100 ha; 0.16% of the world's surface. Worldwide, Romania is ranked #83 for areal extent, and it consitutes 4.81% of the Europe's surface (ranked #12). Romania has 14,856,800 ha of agricultural land which represents 62.3% of the total surface; 0.65 ha per capita. At the national level, 72.5% and 27.5% of soils in Romania can be broadly classed as very poor and good/very good, respectively, based on intrinsic soil characteristics, climate, topography, and ground water. Romania has a specific geographical situation, namely: i) Romanian territory is located in the southeast portion of Central Europe at the cross roads of several high and low pressure centers that form regularly at the borders. The influence of these air masses is altered by the presence in the central regions of the Carpathian mountain chain resulting in a diverse climate with average annual rain fall amounts between 350 to 1,400 mm and average annual temperatures between 2 and 11.5°C. ii) At the national level, almost all soils in the international classification system are present in Romania; each soil type having specific properties and characteristics. iii) On approximately 12.5 million ha (7.5 million ha arable), soil fertility is adversely affected by erosion, acidity, low humus content, extreme texture (clay, sand), excessive moisture, chemical pollution etc. These natural and anthropogenic factors dramatically influence agricultural production. Furthermore, soil, climate, topography, etc. vary widely not only across the country, but also on smaller scales, even across fields within the same farm. In Steppe zone limitative climatic factors, which require differentiation towards soil management use, include: long periods of drought, high temperatures, high frequency winds (wind erosion in area of sands), low relative air humidity, and harsh frosts during winter. Negative phenomena most commonly encountered in this area are salinization, excess water, temporary

  15. Factors influencing tropical island freshwater fishes:Species, status, and management implications in puerto rico [Factores que influencian a los peces tropicales de agua dulce: Especies, estado actual e implicaciones para el manejo en Puerto Rico

    Science.gov (United States)

    Wesley, Neal J.; Lilyestrom, Craig G.; Kwak, T.J.

    2009-01-01

    Anthropogenic effects including river regulation, watershed development, contamination, and fish introductions have substantially affected the majority of freshwater habitats in Europe and North America. This pattern of resource development and degradation is widespread in the tropics, and often little is known about the resources before they are lost. This article describes the freshwater resources of Puerto Rico and identifies factors that threaten conservation of native fishes. The fishes found in freshwater habitats of Puerto Rico represent a moderately diverse assemblage composed of 14 orders, 29 families, and 82 species. There are fewer than 10 species of native peripherally-freshwater fish that require a link to marine systems. Introductions of nonindigenous species have greatly expanded fish diversity in freshwater systems, and native estuarine and marine species (18 families) also commonly enter lowland rivers and brackish lagoons. Environmental alterations, including land use and development, stream channelization, pollution, and the impoundment of rivers, combined with nonnative species introductions threaten the health and sustainability of aquatic resources in Puerto Rico. Six principal areas for attention that are important influences on the current and future status of the freshwater fish resources of Puerto Rico are identified and discussed.

  16. Beyond biodiversity: fish metagenomes.

    Directory of Open Access Journals (Sweden)

    Alba Ardura

    Full Text Available Biodiversity and intra-specific genetic diversity are interrelated and determine the potential of a community to survive and evolve. Both are considered together in Prokaryote communities treated as metagenomes or ensembles of functional variants beyond species limits.Many factors alter biodiversity in higher Eukaryote communities, and human exploitation can be one of the most important for some groups of plants and animals. For example, fisheries can modify both biodiversity and genetic diversity (intra specific. Intra-specific diversity can be drastically altered by overfishing. Intense fishing pressure on one stock may imply extinction of some genetic variants and subsequent loss of intra-specific diversity. The objective of this study was to apply a metagenome approach to fish communities and explore its value for rapid evaluation of biodiversity and genetic diversity at community level. Here we have applied the metagenome approach employing the barcoding target gene coi as a model sequence in catch from four very different fish assemblages exploited by fisheries: freshwater communities from the Amazon River and northern Spanish rivers, and marine communities from the Cantabric and Mediterranean seas.Treating all sequences obtained from each regional catch as a biological unit (exploited community we found that metagenomic diversity indices of the Amazonian catch sample here examined were lower than expected. Reduced diversity could be explained, at least partially, by overexploitation of the fish community that had been independently estimated by other methods.We propose using a metagenome approach for estimating diversity in Eukaryote communities and early evaluating genetic variation losses at multi-species level.

  17. Beyond biodiversity: fish metagenomes.

    Science.gov (United States)

    Ardura, Alba; Planes, Serge; Garcia-Vazquez, Eva

    2011-01-01

    Biodiversity and intra-specific genetic diversity are interrelated and determine the potential of a community to survive and evolve. Both are considered together in Prokaryote communities treated as metagenomes or ensembles of functional variants beyond species limits.Many factors alter biodiversity in higher Eukaryote communities, and human exploitation can be one of the most important for some groups of plants and animals. For example, fisheries can modify both biodiversity and genetic diversity (intra specific). Intra-specific diversity can be drastically altered by overfishing. Intense fishing pressure on one stock may imply extinction of some genetic variants and subsequent loss of intra-specific diversity. The objective of this study was to apply a metagenome approach to fish communities and explore its value for rapid evaluation of biodiversity and genetic diversity at community level. Here we have applied the metagenome approach employing the barcoding target gene coi as a model sequence in catch from four very different fish assemblages exploited by fisheries: freshwater communities from the Amazon River and northern Spanish rivers, and marine communities from the Cantabric and Mediterranean seas.Treating all sequences obtained from each regional catch as a biological unit (exploited community) we found that metagenomic diversity indices of the Amazonian catch sample here examined were lower than expected. Reduced diversity could be explained, at least partially, by overexploitation of the fish community that had been independently estimated by other methods.We propose using a metagenome approach for estimating diversity in Eukaryote communities and early evaluating genetic variation losses at multi-species level.

  18. Age is not a limiting factor for radical radiotherapy in pelvic malignancies

    International Nuclear Information System (INIS)

    Pignon, T.; Horiot, J.C.; Bolla, M.; Poppel, H. van; Bartelink, H.; Roelofsen, F.; Pene, F.; Gerard, A.; Einhorn, N.; Nguyen, T.D.; Vanglabbeke, M.; Scalliet, P.

    1997-01-01

    Background and purpose: Pelvic radiotherapy (RT) toxicity in the elderly is poorly documented. We developed a study aiming to evaluate whether or not a limit of age could be identified beyond which toxicities in patients receiving pelvic RT were more frequent or more severe. Material and methods: 1619 patients with pelvic cancers enrolled in nine EORTC trials, RT arms, were retrospectively studied. Patients were split into six age ranges from 50 years to 70 years and over. Survivals and late toxicity occurrence were calculated with the Kaplan-Meier method and comparison between age groups with the logrank test. A trend test was done to examine if chronological age had an impact on acute toxicity occurrence. Results: Survival was comparable in each age group for prostate (P=0.18), uterus (0.41), anal canal cancer (P=0.6) and slightly better for the younger group of rectum cancer (P=0.04). A total of 1722 acute and 514 late grade ≥1 were recorded. Acute nausea/vomiting, skin complications and performance status deterioration were significantly more frequent in younger patients. There was no trend toward more aged patients to experience diarrhea (P=0.149) and after adjustment on RT dose, acute urinary complications were observed equally in each age range (P=0.32). Eighty percent of patients were free of late complication at 5 years in each age range (P=0.79). For the grade >2 late side-effects, a plateau was observed after 1 year at near 9% without any difference (P=0.06) nor trend (P=0.13) between age-groups. Conclusion: Age per se is not a limiting factor for radical radiotherapy in pelvic malignancies

  19. Factors affecting the quality of fish caught by Native Americans in the Zone 6 fishery 1991 through 1993

    Energy Technology Data Exchange (ETDEWEB)

    Abernethy, C.S.

    1994-09-01

    A program to monitor the salmon and steelhead (Oncorhynchus spp.) fishery in the lower Columbia River (Zone 6 fishery) was initiated in 1991 to respond to questions and comments frequently made by Native Americans at public meetings. Native Americans were concerned that the quality of the Columbia River had deteriorated and that the poor environmental conditions had affected the health and quality of fish they relied on for subsistence, ceremonial, religious, and commercial purposes. They also feared that eating contaminated fish might endanger the health of their children and future generations. Operations at the Hanford Site were listed as one of many causes of the deteriorating environment. Fisheries pathologists concluded that most of the external symptoms on fish were related to bacterial infection of gill net abrasions and pre-spawning trauma, and were not caused by pollution or contamination of the Columbia River. The pathologists also stated that consumption of the fish posed no threat to human consumers.

  20. Factors responsible for the emergence of arboviruses; strategies, challenges and limitations for their control.

    Science.gov (United States)

    Liang, Guodong; Gao, Xiaoyan; Gould, Ernest A

    2015-03-01

    Slave trading of Africans to the Americas, during the 16th to the 19th century was responsible for the first recorded emergence in the New World of two arthropod-borne viruses (arboviruses), yellow fever virus and dengue virus. Many other arboviruses have since emerged from their sylvatic reservoirs and dispersed globally due to evolving factors that include anthropological behaviour, commercial transportation and land-remediation. Here, we outline some characteristics of these highly divergent arboviruses, including the variety of life cycles they have developed and the mechanisms by which they have adapted to evolving changes in habitat and host availability. We cite recent examples of virus emergence that exemplify how arboviruses have exploited the consequences of the modern human lifestyle. Using our current understanding of these viruses, we also attempt to demonstrate some of the limitations encountered in developing control strategies to reduce the impact of future emerging arbovirus diseases. Finally, we present recommendations for development by an international panel of experts reporting directly to World Health Organization, with the intention of providing internationally acceptable guidelines for improving emerging arbovirus disease control strategies. Success in these aims should alleviate the suffering and costs encountered during recent decades when arboviruses have emerged from their sylvatic environment.

  1. Transport and homeostasis of potassium and phosphate: limiting factors for sustainable crop production.

    Science.gov (United States)

    Luan, Mingda; Tang, Ren-Jie; Tang, Yumei; Tian, Wang; Hou, Congong; Zhao, Fugeng; Lan, Wenzhi; Luan, Sheng

    2017-06-01

    Potassium (K) and phosphate (Pi) are both macronutrients essential for plant growth and crop production, but the unrenewable resources of phosphorus rock and potash have become limiting factors for food security. One critical measure to help solve this problem is to improve nutrient use efficiency (NUE) in plants by understanding and engineering genetic networks for ion uptake, translocation, and storage. Plants have evolved multiple systems to adapt to various nutrient conditions for growth and production. Within the NUE networks, transport proteins and their regulators are the primary players for maintaining nutrient homeostasis and could be utilized to engineer high NUE traits in crop plants. A large number of publications have detailed K+ and Pi transport proteins in plants over the past three decades. Meanwhile, the discovery and validation of their regulatory mechanisms are fast-track topics for research. Here, we provide an overview of K+ and Pi transport proteins and their regulatory mechanisms, which participate in the uptake, translocation, storage, and recycling of these nutrients in plants. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  2. Biodiversities and limiting factors of Lashgardar Protected Area (LPA, Hamadan Province, Iran

    Directory of Open Access Journals (Sweden)

    MAHDI REYAHI KHORAM

    2010-10-01

    Full Text Available Reyahi-Khoram M, Norisharikabad V (2011 Biodiversities and limiting factors of Lashgardar Protected Area (LPA, Hamadan Province, Iran. Biodiversitas 12: 216-221. Lashgardar Protected Area (LPA located in Hamadan Province in Iran, it is a mountainous and plain area and proximal to Malayer Township. In 1991, the region was known as a protected area for increasing wild animals' population. This research has been conducted during 2001 through 2009. Plant and animal species of the region were identified and statistics of the population of animal flagship species were gathered. In this research, valid academic resources were used for identification of animal and plant species. Geographic Information System (GIS has been used to evaluate the land as main tool. The software used was Arc View (version 3.2a scale was 1/50,000. Due to cold mountainous climate, the region is covered by a wide diversity of trees, shrubs, grasses and herbs. There were 18 species of mammals as well as 75 bird species in LPA. Most abundant mammalian population belongs to wild sheep (558 animals and the second abundance was related to wild goat (515 animals. Also, the most abundant bird species belong to ortolans. Result of the present study showed that construction of connection roads in vicinity the region, establishment of factories inside and around the region, military garrison, unauthorized grazing, unlawful hunting, and Ahangaran mine and rail road have all exposed put LPA to serious threat and danger.

  3. [Limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou].

    Science.gov (United States)

    Lin, Wen-Jie; Xiao, Tang-Fu; Ao, Zi-Qiang; Xing, Jun; Ma, Huan-Cheng; Hu, Ting-Xing

    2007-03-01

    With indigenous zinc smelting waste residue, contaminated soil and background soil as test substrates, a pot experiment was conducted to study the growth characteristics of Lolium perenne and Trifolium pretense on these substrates. The results showed that the major limiting factors of waste land revegetation in indigenous zinc smelting areas of western Guizhou were the salt-alkali stress and the lower contents of organic matter, total N, available N and total K. The heavy metals in waste residue had a high concentration, but their available forms only occupied a small proportion, with low toxicity to plant but having potential harmful risk. Contaminated soil had lower concentrations of heavy metals than waste residue, but its contained heavy metals were more in available form. The constraints of revegetation on contaminated soil were the toxicity of heavy metals and the low contents of available P and K. Mixing contaminated soil with zinc smelting waste residue could be one of the effective approaches for the substrate amendment in indigenous zinc smelting areas.

  4. Theory of factors limiting high gradient operation of warm accelerating structures

    Energy Technology Data Exchange (ETDEWEB)

    Nusinovich, Gregory S. [University of Maryland; Antonsen, Thomas M. [University of Maryland; Kishek, Rami [University of Maryland

    2014-07-25

    This final report summarizes the research performed during the time period from 8/1/2010 to 7/31/2013. It consists of two parts describing our studies in two directions: (a) analysis of factors limiting operation of dielectric-loaded accelerating (DLA) structures where the main problem is the occurrence of multipactor on dielectric surfaces, and (b) studies of effects associated with either RF magnetic or RF electric fields which may cause the RF breakdown in high-gradient metallic accelerating structures. In the studies of DLA structures, at least, two accomplishments should be mentioned: the development of a 3D non-stationary, self-consistent code describing the multipactor phenomena and yielding very good agreement with some experimental data obtained in joint ANL/NRL experiments. In the metallic structures, such phenomena as the heating and melting of micro-particles (metallic dust) by RF electric and magnetic fields in single-shot and rep-rate regimes is analyzed. Also, such processes in micro-protrusions on the structure surfaces as heating and melting due to the field emitted current and the Nottingham effect are thoroughly investigated with the account for space charge of emitted current on the field emission from the tip.

  5. An analysis of factors affecting participation behavior of limited resource farmers in agricultural cost-share programs in Alabama

    Science.gov (United States)

    Okwudili Onianwa; Gerald Wheelock; Buddhi Gyawali; Jianbang Gan; Mark Dubois; John Schelhas

    2004-01-01

    This study examines factors that affect the participation behavior of limited resource farmers in agricultural cost-share programs in Alabama. The data were generated from a survey administered to a sample of limited resource farm operators. A binary logit model was employed to analyze the data. Results indicate that college education, age, gross sales, ratio of owned...

  6. Interministerial decree of 10 February 1988 fixing the derived limits of the air concentration and the annual intake limit and the values of the quality factor and the neutron fluence rate

    International Nuclear Information System (INIS)

    1988-01-01

    This decree establishes the derived concentration limits in the air and annual inhalation limits for the radioisotopes and the values of the quality factors and the conversion factors fluence/dose equivalent for neutrons and protons

  7. The effects of fishing extend well beyond the direct impact on the ...

    African Journals Online (AJOL)

    It is difficult to predict indirect effects of fishing on the ecosystem and ... Formerly Marine & Coastal Management, Department of Environmental Affairs and Tourism, Private Bag X2, Rogge Bay 8012, Cape Town, ..... factors would have tended to limit fishing mortality ..... also thank the Eritrean Human Resource Development.

  8. Posthodiplostomum cuticola (Digenea: Diplostomatidae) in intermediate fish hosts: factors contributing to the parasite infection and prey selection by the definitive bird host

    Czech Academy of Sciences Publication Activity Database

    Ondračková, Markéta; Šimková, A.; Gelnar, M.; Jurajda, Pavel

    2004-01-01

    Roč. 129, č. 6 (2004), s. 761-770 ISSN 0031-1820 R&D Projects: GA ČR GA524/02/0924; GA ČR GP524/03/P108 Institutional research plan: CEZ:AV0Z6093917 Keywords : fish assemblages * intermediate host * complex life-cycle Subject RIV: EG - Zoology Impact factor: 1.685, year: 2004

  9. Fish Allergy

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Fish Allergy KidsHealth / For Parents / Fish Allergy What's in this ... Print en español Alergia al pescado About Fish Allergy A fish allergy is not exactly the same ...

  10. Updating Environmental Media Concentration Limits and Uncertainty factors in the ERICA Tool

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J.E.; Hosseini, A. [Norwegian Radiation Protection Authority, P.O. Box 55, N-1332 Oesteraas (Norway); Alfonso, B.; Avila, R. [Facilia AB, S-167 51 Bromma (Sweden); Beresford, N.A. [Centre for Ecology and Hydrology, CEH-Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster LA 1 4AP (United Kingdom); Copplestone, D. [Dept. Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA (United Kingdom)

    2014-07-01

    Tiered approaches have become a standard means of structuring information in the process of conducting environmental risk assessments. For cases involving the assessment of impacts on wildlife from ionising radiation, the ERICA integrated approach and its supporting software (The ERICA Tool) provides such a structure, splitting the system into two generic screening tiers and a third site-specific tier. The first Tier is very simple, based around Environmental Media Concentration Limits, EMCLs, and requires minimal input from the assessor. The second Tier, although still a screening tier, calculates dose rates and requires more detailed input from the assessor allowing for scrutiny and editing of default parameters in the process. A key element of Tier 2 involves the application of Uncertainty Factors, UFs. Such factors reflect our knowledge concerning probability distribution functions and provide a way of incorporating conservatism into the assessment by considering high percentile values in underlying parameters. Following its launch in 2007, there have been significant developments regarding certain components of the ERICA integrated approach. Most notably, an extended international collation of concentration ratio data has precipitated the need to update parameter values in the Tools databases. In addition, more considered guidance has been developed with regards to filling knowledge gaps in the absence of transfer data. Furthermore, the efficacy of the methods used in assigning probability distribution functions has been questioned leading to an acknowledgement from the developers that the methods were not described in enough detail nor were the justifications for applying the selected approach provided in a convincing way. This has implications for the EMCL values which are derived probabilistically using parameters including concentration ratios. Furthermore, there are implications for UF derivation that relies upon a robust consideration of underlying

  11. Effect of a plant sterol, fish oil and B vitamin combination on cardiovascular risk factors in hypercholesterolemic children and adolescents: a pilot study

    Directory of Open Access Journals (Sweden)

    Garaiova Iveta

    2013-01-01

    Full Text Available Abstract Background Assessment of cardiovascular disease (CVD risk factors can predict clinical manifestations of atherosclerosis in adulthood. In this pilot study with hypercholesterolemic children and adolescents, we investigated the effects of a combination of plant sterols, fish oil and B vitamins on the levels of four independent risk factors for CVD; LDL-cholesterol, triacylglycerols, C-reactive protein and homocysteine. Methods Twenty five participants (mean age 16 y, BMI 23 kg/m2 received daily for a period of 16 weeks an emulsified preparation comprising plant sterols esters (1300 mg, fish oil (providing 1000 mg eicosapentaenoic acid (EPA plus docosahexaenoic acid (DHA and vitamins B12 (50 μg, B6 (2.5 mg, folic acid (800 μg and coenzyme Q10 (3 mg. Atherogenic and inflammatory risk factors, plasma lipophilic vitamins, provitamins and fatty acids were measured at baseline, week 8 and 16. Results The serum total cholesterol, LDL- cholesterol, VLDL-cholesterol, subfractions LDL-2, IDL-1, IDL-2 and plasma homocysteine levels were significantly reduced at the end of the intervention period (pp Conclusions Daily intake of a combination of plant sterols, fish oil and B vitamins may modulate the lipid profile of hypercholesterolemic children and adolescents. Trial registration Current Controlled Trials ISRCTN89549017

  12. Factors associated with use of slip-resistant shoes in US limited-service restaurant workers.

    Science.gov (United States)

    Verma, Santosh K; Courtney, Theodore K; Corns, Helen L; Huang, Yueng-Hsiang; Lombardi, David A; Chang, Wen-Ruey; Brennan, Melanye J; Perry, Melissa J

    2012-06-01

    Slips and falls are a leading cause of injury at work. Several studies have indicated that slip-resistant shoes can reduce the risk of occupational slips and falls. Few studies, however, have examined the determinants of slip-resistant shoe use. This study examined the individual and workplace factors associated with slip-resistant shoe use. 475 workers from 36 limited-service restaurants in the USA participated in a study of workplace slipping. Demographic and job characteristic information about each participant was collected. Restaurant managers provided information on whether slip-resistant shoes were provided and paid for by the employer and whether any guidance was given regarding slip-resistant shoe use when they were not provided. Kitchen floor coefficient of friction was measured. Slip-resistant status of the shoes was determined by noting the presence of a 'slip-resistant' marking on the sole. Poisson regression with robust SE was used to calculate prevalence ratios. 320 participants wore slip-resistant shoes (67%). In the multivariate analysis, the prevalence of slip-resistant shoe use was lowest in 15-19-year age group. Women were more likely to wear slip-resistant shoes (prevalence ratio 1.18, 95% CI 1.07 to 1.31). The prevalence of slip-resistant shoe use was lower when no guidance regarding slip-resistant shoes was given as compared to when they were provided by the employer (prevalence ratio 0.66, 95% CI 0.55 to 0.79). Education level, job tenure and the mean coefficient of friction had no significant effects on the use of slip-resistant shoes. Provision of slip-resistant shoes was the strongest predictor of their use. Given their effectiveness and low cost, employers should consider providing slip-resistant shoes at work.

  13. Weathering as the limiting factor of denudation in the Western escarpment of the Andes

    Science.gov (United States)

    Abbühl, L. M.; Schlunegger, F.; Kracht, O.; Ramseyer, K.; Rieke-Zapp, D.; Aldahan, A.; von Blanckenburg, F.

    2009-04-01

    additional river profile knickzone in the transition zone between the easterlies and the westerlies. Analysis of 10Be in quartz of river-born sand and of bedrock reveals that denudation correlates positively with the present-day rainfall pattern related to the easterlies. Denudation rates in the headwaters range from 0.14 mm/year in Northern Peru down to 0.05 mm/yr in Northern Chile (Kober et al., 2007). In addition, 10Be-based denudation rates reveal a decreasing trend from the Cordillera to the Pacific coast that positively correlates with the decreasing precipitation rate, irrespective of the nature of the bedrock. Interestingly, the 10Be analysis conducted in the Piura system reveals no influence of the episodic precipitation in relation to El Niño on the sediment production rates. In summary, the pattern of denudation rates together with morphometric observations and quantitative denudation rate estimates strongly hints at weathering being the driving but also limiting factor of denudation. Accordingly, in the western Peruvian Andes, sediment production and export are most probably controlled by the pattern and rate of precipitation. Kober, F., Ivy-Ochs, S., Schlunegger, F., Baur, H., Kubik, P. W., and Wieler, R. (2007). Denudation rates and a topography-driven rainfall threshold in northern Chile: Multiple cosmogenic nuclide data and sediment yield budgets. Geomorphology 83, 97-120.

  14. Fish oil improves motor function, limits blood-brain barrier disruption, and reduces Mmp9 gene expression in a rat model of juvenile traumatic brain injury.

    Science.gov (United States)

    Russell, K L; Berman, N E J; Gregg, P R A; Levant, B

    2014-01-01

    The effects of an oral fish oil treatment regimen on sensorimotor, blood-brain barrier, and biochemical outcomes of traumatic brain injury (TBI) were investigated in a juvenile rat model. Seventeen-day old Long-Evans rats were given a 15mL/kg fish oil (2.01g/kg EPA, 1.34g/kg DHA) or soybean oil dose via oral gavage 30min prior to being subjected to a controlled cortical impact injury or sham surgery, followed by daily doses for seven days. Fish oil treatment resulted in less severe hindlimb deficits after TBI as assessed with the beam walk test, decreased cerebral IgG infiltration, and decreased TBI-induced expression of the Mmp9 gene one day after injury. These results indicate that fish oil improved functional outcome after TBI resulting, at least in part from decreased disruption of the blood-brain barrier through a mechanism that includes attenuation of TBI-induced expression of Mmp9. © 2013 Elsevier Ltd. All rights reserved.

  15. Sediment distribution coefficients (KD) and concentration factors (CF) in fish for natural radionuclides in a pond of a tropical region and their contributions to estimations of internal absorbed dose rate in fish

    International Nuclear Information System (INIS)

    Souza Pereira, Wagner de; Kelecom, Alphonse

    2008-01-01

    Attention has been paid only recently to the protection of biota against radiation effects. Protection is being considered through modeling of the calculation of absorbed dose rate. In these models, the inputs are the fluxes of radionuclides of environmental concern and their resulting distribution between environmental compartments. Such distribution is estimated for dispersion models. In freshwater systems and when fish is used as biomaker, relevant environmental transfer parameters are transfer between sediment and water (sediment distribution coefficients KD, in l kg -1 ), and between water and fish (concentration factor CF, in l kg -1 ). These coefficients are under the influence of a number o physical, chemical and biological factors, and display following the literature a great variability. The present work establishes the KD's and CF's for uranium, thorium, radium and lead for two ponds: one that receives treated effluents from an ore treatment unit (UTM) situated at Pocos de Caldas, Minas Gerais, Brazil and the other pond from the uranium concentration unit (URA) situated at Caetite, Bahia, Brazil, and for fish used as biomarker. It intends also to compare these parameters with the values recommended by IAEA. Depending on considered radionuclide and on the site, CF's (l kg -1 ) observed values were of the same magnitude as, or one order of magnitude lower than recommended by IAEA. KD's (l kg -1 ) observed values were found of the same magnitude as those recommended by IAEA, approximately 10 times lower or up to 100 times higher than recommended by IAEA, again depending on the radionuclides and on the site. It can be concluded that local parameters should be established in order to obtain a more accurate estimative of biota exposition from man activities. (author)

  16. Limited differences in fish and benthic communities and possible cascading effects inside and outside a protected marine area in Sagres (SW Portugal).

    Science.gov (United States)

    Gil Fernández, C; Paulo, D; Serrão, E A; Engelen, A H

    2016-03-01

    Marine protected areas (MPAs) are a relatively recent fisheries management and conservation tool for conservation of marine ecosystems and serve as experimental grounds to assess trophic cascade effects in areas were fishing is restricted to some extent. A series of descriptive field studies were performed to assess fish and benthic communities between two areas within a newly established MPA in SW Portugal. We characterized benthic macroalgal composition and determined the size, density and biomass of the main benthic predatory and herbivorous fish species as well as the main benthic herbivorous invertebrates to assess indications of top-down control on the phytobenthic assemblages. Fish species were identical inside and outside the MPA, in both cases Sarpa salpa was the most abundant fish herbivore and Diplodus spp. accounted for the great majority of the benthic predators. However, size and biomass of D. spp. were higher inside than outside the MPA. The main herbivorous invertebrate was the sea urchin Paracentrotus lividus, which was smaller and predominantly showing a crevice-dwelling behaviour in the MPA. In addition, P. lividus size frequency distribution showed a unimodal pattern outside and a bimodal pattern inside the MPA. We found significant differences in the algal assemblages between inside and outside the MPA, with higher abundance of turf and foliose algae inside, and articulated calcareous and corticated macrophytes outside the MPA, but no differences in the invasive Asparagopsis spp. The obtained results show differences in predatory fish and benthic community structure, but not in species richness, inside and outside the MPA. We hypothesize these differences lead to variation in species interactions: directly through predation and indirectly via affecting sea urchins behavioural patterns, predators might drive changes in macroalgal assemblages via trophic cascade in the study area. However due to non-biological differences between the two areas it

  17. Radiation induced lipid oxidation in fish

    International Nuclear Information System (INIS)

    Snauwaert, F.; Tobback, P.; Maes, E.; Thyssen, J.

    1977-01-01

    Oxidative rancidity in herring and redfish was studied as a function of the applied irradiation dose, the storage time and storage temperature and the packaging conditions. - Measurements of the TBA (thiobarbituric acid) value and the peroxide value were used to evaluate the degree of oxidation of lipids, and were related with sensory scores. - Especially for the fatty fish species (herring) irradiation accelerated lipid oxidation and induced oxidative rancidity. Irradiation of vacuum-packed herring fillets and subsequent storage at +2 C seems to be an interesting process. For the experiments conducted on a semi-fatty fish (redfish), oxidative rancidity was never the limiting factor for organoleptic acceptability. (orig.) [de

  18. Sequence and Expression Analysis of Interferon Regulatory Factor 10 (IRF10 in Three Diverse Teleost Fish Reveals Its Role in Antiviral Defense.

    Directory of Open Access Journals (Sweden)

    Qiaoqing Xu

    Full Text Available Interferon regulatory factor (IRF 10 was first found in birds and is present in the genome of other tetrapods (but not humans and mice, as well as in teleost fish. The functional role of IRF10 in vertebrate immunity is relatively unknown compared to IRF1-9. The target of this research was to clone and characterize the IRF10 genes in three economically important fish species that will facilitate future evaluation of this molecule in fish innate and adaptive immunity.In the present study, a single IRF10 gene was cloned in grass carp Ctenopharyngodon idella and Asian swamp eel Monopterus albus, and two, named IRF10a and IRF10b, in rainbow trout Oncorhynchus mykiss. The fish IRF10 molecules share highest identities to other vertebrate IRF10s, and have a well conserved DNA binding domain, IRF-associated domain, and an 8 exon/7 intron structure with conserved intron phase. The presence of an upstream ATG or open reading frame (ORF in the 5'-untranslated region of different fish IRF10 cDNA sequences suggests potential regulation at the translational level, and this has been verified by in vitro transcription/translation experiments of the trout IRF10a cDNA, but would still need to be validated in fish cells.Both trout IRF10 paralogues are highly expressed in thymus, blood and spleen but are relatively low in head kidney and caudal kidney. Trout IRF10b expression is significantly higher than IRF10a in integumentary tissues i.e. gills, scales, skin, intestine, adipose fin and tail fins, suggesting that IRF10b may be more important in mucosal immunity. The expression of both trout IRF10 paralogues is up-regulated by recombinant IFN-γ. The expression of the IRF10 genes is highly induced by Poly I:C in vitro and in vivo, and by viral infection, but is less responsive to peptidoglycan and bacterial infection, suggesting an important role of fish IRF10 in antiviral defense.

  19. Obesity as a risk factor for developing functional limitation among older adults: A conditional inference tree analysis.

    Science.gov (United States)

    Cheng, Feon W; Gao, Xiang; Bao, Le; Mitchell, Diane C; Wood, Craig; Sliwinski, Martin J; Smiciklas-Wright, Helen; Still, Christopher D; Rolston, David D K; Jensen, Gordon L

    2017-07-01

    To examine the risk factors of developing functional decline and make probabilistic predictions by using a tree-based method that allows higher order polynomials and interactions of the risk factors. The conditional inference tree analysis, a data mining approach, was used to construct a risk stratification algorithm for developing functional limitation based on BMI and other potential risk factors for disability in 1,951 older adults without functional limitations at baseline (baseline age 73.1 ± 4.2 y). We also analyzed the data with multivariate stepwise logistic regression and compared the two approaches (e.g., cross-validation). Over a mean of 9.2 ± 1.7 years of follow-up, 221 individuals developed functional limitation. Higher BMI, age, and comorbidity were consistently identified as significant risk factors for functional decline using both methods. Based on these factors, individuals were stratified into four risk groups via the conditional inference tree analysis. Compared to the low-risk group, all other groups had a significantly higher risk of developing functional limitation. The odds ratio comparing two extreme categories was 9.09 (95% confidence interval: 4.68, 17.6). Higher BMI, age, and comorbid disease were consistently identified as significant risk factors for functional decline among older individuals across all approaches and analyses. © 2017 The Obesity Society.

  20. ASSOCIATION BETWEEN THE PRESENCE OF A 38 kDa FACTOR IN THE SEMINAL PLASMA AND INHIBITION OF SPERM MOTILITY IN JUNDIÁ FISH Rhamdia quelen

    Directory of Open Access Journals (Sweden)

    Vinicius Farias Campos

    2010-06-01

    Full Text Available Protein factors have been identified in the seminal plasmaof fish and mammal species and, in some situations, associatedto sperm quality indicators. However, for jundiá fish (Rhamdiaquelen, such factors and those potential associations remainunknown. In the present study, we aimed to identify some proteinfactors present in the seminal plasma of jundiá fish and to evaluatetheir association to sperm motility. SDS-PAGE was used to identify14 bands, with molecular weight ranging from 217.1 to 7.1 kDa.Sperm motility was evaluated for 21 males. Four protein bands(81.5; 60.4; 33.6; and 25.5 kDa were present in all seminal plasmasamples. One protein band with molecular weight of 38.3 kDa wasassociated to reduced sperm motility of jundiá (P<0.01, since itwas detected in 91.4% of the samples having motility lower than80%. These results suggest that this seminal protein band associatedto lower sperm motility may be considered a potential biochemicalmarker for sperm quality.

  1. Fish consumption and track to a fish feed formulation

    Science.gov (United States)

    Cai-Juan, Soong; Ramli, Razamin; Rahman, Rosshairy Abdul

    2015-12-01

    Strategically located in the equator, Malaysia is blessed with plenty of fish supply. The high demand in fish consumption has helped the development in the fishery industry and provided numerous jobs in the secondary sector, contributing significantly to the nation's income. A survey was conducted to understand the trend of current demands for fish for the purpose of designing a feed formulation, which is still limited in this area of study. Results showed that grouper fish in restaurants commanded a very high price compared to other species of fish. Tiger grouper gained the highest demand in most restaurants, while giant grouper had the highest price in restaurants. Due to the demand and challenges to culture this type of fish, a framework for fish feed formulation is proposed. The formulation framework when materialized could be an alternative to the use of trash fish as the feed for grouper.

  2. Development of low level 226Ra analysis for live fish using gamma-ray spectrometry

    Science.gov (United States)

    Chandani, Z.; Prestwich, W. V.; Byun, S. H.

    2017-06-01

    A low level 226Ra analysis method for live fish was developed using a 4π NaI(Tl) gamma-ray spectrometer. In order to find out the best algorithm for accomplishing the lowest detection limit, the gamma-ray spectrum from a 226Ra point was collected and nine different methods were attempted for spectral analysis. The lowest detection limit of 0.99 Bq for an hour counting occurred when the spectrum was integrated in the energy region of 50-2520 keV. To extend 226Ra analysis to live fish, a Monte Carlo simulation model with a cylindrical fish in a water container was built using the MCNP code. From simulation results, the spatial distribution of the efficiency and the efficiency correction factor for the live fish model were determined. The MCNP model will be able to be conveniently modified when a different fish or container geometry is employed as fish grow up in real experiments.

  3. Effects of fire on fish populations: Landscape perspectives on persistance of native fishes and nonnative fish invasions

    Science.gov (United States)

    Dunham, J.B.; Young, M.; Gresswell, Robert E.; Rieman, B.

    2003-01-01

    Our limited understanding of the short and long-term effects of fire on fish contributes to considerable uncertainty in assessments of the risks and benefits of fire management alternatives. A primary concern among the many potential effects of fire is the effects of fire and fire management on persistence of native fish populations. Limited evidence suggests vulnerability of fish to fire is contingent upon the quality of affected habitats, the amount and distribution of habitat (habitat fragmentation), and habitat specificity of the species in question. Species with narrow habitat requirements in highly degraded and fragmented systems are likely to be most vulnerable to fire and fire-related disturbance. In addition to effects of fire on native fish, there are growing concerns about the effects of fire on nonnative fish invasions. The role of fire in facilitating invasions by nonnative fishes is unknown, but experience with other species suggests some forms of disturbance associated with fire may facilitate invasion. Management efforts to promote persistence of fishes in fire-prone landscapes can take the form of four basic alternatives: (1) pre-fire management; (2) post-fire management; (3) managing fire itself (e.g. fire fighting); and (4) monitoring and adaptive management. Among these alternatives, pre-fire management is likely to be most effective. Effective pre-fire management activities will address factors that may render fish populations more vulnerable to the effects of fire (e.g. habitat degradation, fragmentation, and nonnative species). Post-fire management is also potentially important, but suffers from being a reactive approach that may not address threats in time to avert them. Managing fire itself can be important in some contexts, but negative consequences for fish populations are possible (e.g. toxicity of fire fighting chemicals to fish). Monitoring and adaptive management can provide important new information for evaluating alternatives, but

  4. Risky Sexual Behavior among Rural Female Adolescents in Malaysia: A Limited Role of Protective Factors

    OpenAIRE

    Ahmadian, Maryam; Hamsan, Hanina H.; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

    2014-01-01

    Purpose: This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. Methods: We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, a...

  5. Consumers’ attitude towards fish meat

    Directory of Open Access Journals (Sweden)

    Francesca Conte

    2014-09-01

    Full Text Available The overall aim of this paper is to show the factors that may affect consumers’ attitude towards farmed fish products. Consumers ask new products on the basis of different quality attributes: stability, safety, composition, better health effects, environment protection, etc. Different and controversial opinions on farmed and wild fish are also explored by literature review. The authors pay attention also to fish welfare as an emerging issue and effective information about fish products as a factor exerting a positive influence on consumers’ decision of purchase. Some relevant legislative notes on the paper’s topics are also cited. The qualitative aspects of aquaculture fish and the consumers’ demand and choice need further studies, according to some factors, such as the changing consumers’ attitudes towards fish products, the different fish quality perception and the development in the aquaculture systems.

  6. Human Factors Assessment of the UH-60M Crew Station During the Limited User Test (LUT)

    National Research Council Canada - National Science Library

    Havir, Thomas J; Durbin, David B; Frederick, Lorraine J; Hicks, Jamison S

    2006-01-01

    The utility helicopter (UH)-60M Product Manager requested the U.S. Army Research Laboratory's Human Research and Engineering Directorate to participate in the Limited User Test for the UH-60M Black Hawk...

  7. Insights from mercury stable isotopes into factors affecting the internal body burden of methylmercury in frequent fish consumers

    Directory of Open Access Journals (Sweden)

    Miling Li

    2016-05-01

    Full Text Available Abstract Methylmercury (MeHg exposure can cause adverse health effects in children and adults and is predominantly from seafood consumption in the United States (U.S.. Here we examine evidence for differences in MeHg uptake and metabolism in U.S. individuals who consume three or more fish meals per week. We hypothesized based on prior research that some individuals have enhanced capacity to demethylate ingested MeHg and this will be reflected by a greater than typically observed δ202Hg offset in their hair relative to consumed fish (∼2 ‰. We used self-reported seafood intake data to identify individuals with hair Hg concentrations that agree extremely well with reported ingestion and those that do not. Approximately one-third of individuals in our survey population had hair Hg levels below the lower bound of probabilistic exposure modeling based on dietary intake data. The Δ199Hg values measured in the hair of a subset of individuals with the highest and lowest discrepancies between modeled and measured exposures are consistent with self-reported fish intake, validating the reliability of their dietary recall information. The δ202Hg offset between fish and human hair is similar for low- and high-discrepancy individuals, suggesting enhanced in vivo demethylation does not explain some individuals with hair Hg levels equivalent to non-fish consumers (0.10 ug/g. Using the probabilistic exposure model, we find dietary MeHg absorption efficiencies required to explain hair Hg levels in these high-discrepancy individuals are on average lower than 14% (range: 1%–72%. Exposure modeling for MeHg typically assumes a range of 91–97% and our results emphasize much greater inter-individual variability in this value.

  8. Perfluoroalkyl substances and fish consumption.

    Science.gov (United States)

    Christensen, Krista Y; Raymond, Michelle; Blackowicz, Michael; Liu, Yangyang; Thompson, Brooke A; Anderson, Henry A; Turyk, Mary

    2017-04-01

    Perfluoroalkyl substances (PFAS) are an emerging class of contaminants. Certain PFAS are regulated or voluntarily limited due to concern about environmental persistence and adverse health effects, including thyroid disease and dyslipidemia. The major source of PFAS exposure in the general population is thought to be consumption of seafood. In this analysis we examine PFAS levels and their determinants, as well as associations between PFAS levels and self-reported fish and shellfish consumption, using a representative sample of the U.S. Data on PFAS levels and self-reported fish consumption over the past 30 days were collected from the 2007-2008, 2009-2010, 2011-2012, and 2013-2014 cycles of the National Health and Nutrition Examination Survey. Twelve different PFAS were measured in serum samples from participants. Ordinary least squares regression models were used to identify factors (demographic characteristics and fish consumption habits) associated with serum PFAS concentrations. Additional models were further adjusted for other potential exposures including military service and consumption of ready-to-eat and fast foods. Seven PFAS were detected in at least 30% of participants and were examined in subsequent analyses (PFDA, PFOA, PFOS, PFHxS, MPAH, PFNA, PFUA). The PFAS with the highest concentrations were PFOS, followed by PFOA, PFHxS and PFNA (medians of 8.3, 2.7, 1.5 and 1.0ng/mL). Fish consumption was generally low, with a median of 1.2 fish meals and 0.14 shellfish meals, reported over the past 30 days. After adjusting for demographic characteristics, total fish consumption was associated with reduced MPAH, and with elevated PFDE, PFNA and PFuDA. Shellfish consumption was associated with elevations of all PFAS examined except MPAH. Certain specific fish and shellfish types were also associated with specific PFAS. Adjustment for additional exposure variables resulted in little to no change in effect estimates for seafood variables. PFAS are emerging

  9. Apolipoprotein A-I Limits the Negative Effect of Tumor Necrosis Factor on Lymphangiogenesis

    NARCIS (Netherlands)

    Bisoendial, Radjesh; Tabet, Fatiha; Tak, Paul P.; Petrides, Francine; Cuesta Torres, Luisa F.; Hou, Liming; Cook, Adam; Barter, Philip J.; Weninger, Wolfgang; Rye, Kerry-Anne

    2015-01-01

    Lymphatic endothelial dysfunction underlies the pathogenesis of many chronic inflammatory disorders. The proinflammatory cytokine tumor necrosis factor (TNF) is known for its role in disrupting the function of the lymphatic vasculature. This study investigates the ability of apolipoprotein (apo)

  10. [Limiting a Medline/PubMed query to the "best" articles using the JCR relative impact factor].

    Science.gov (United States)

    Avillach, P; Kerdelhué, G; Devos, P; Maisonneuve, H; Darmoni, S J

    2014-12-01

    Medline/PubMed is the most frequently used medical bibliographic research database. The aim of this study was to propose a new generic method to limit any Medline/PubMed query based on the relative impact factor and the A & B categories of the SIGAPS score. The entire PubMed corpus was used for the feasibility study, then ten frequent diseases in terms of PubMed indexing and the citations of four Nobel prize winners. The relative impact factor (RIF) was calculated by medical specialty defined in Journal Citation Reports. The two queries, which included all the journals in category A (or A OR B), were added to any Medline/PubMed query as a central point of the feasibility study. Limitation using the SIGAPS category A was larger than the when using the Core Clinical Journals (CCJ): 15.65% of PubMed corpus vs 8.64% for CCJ. The response time of this limit applied to the entire PubMed corpus was less than two seconds. For five diseases out of ten, limiting the citations with the RIF was more effective than with the CCJ. For the four Nobel prize winners, limiting the citations with the RIF was more effective than the CCJ. The feasibility study to apply a new filter based on the relative impact factor on any Medline/PubMed query was positive. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  11. Habitats as surrogates of taxonomic and functional fish assemblages in coral reef ecosystems: a critical analysis of factors driving effectiveness.

    Directory of Open Access Journals (Sweden)

    Simon Van Wynsberge

    Full Text Available Species check-lists are helpful to establish Marine Protected Areas (MPAs and protect local richness, endemicity, rarity, and biodiversity in general. However, such exhaustive taxonomic lists (i.e., true surrogate of biodiversity require extensive and expensive censuses, and the use of estimator surrogates (e.g., habitats is an appealing alternative. In truth, surrogate effectiveness appears from the literature highly variable both in marine and terrestrial ecosystems, making it difficult to provide practical recommendations for managers. Here, we evaluate how the biodiversity reference data set and its inherent bias can influence effectiveness. Specifically, we defined habitats by geomorphology, rugosity, and benthic cover and architecture criteria, and mapped them with satellite images for a New-Caledonian site. Fish taxonomic and functional lists were elaborated from Underwater Visual Censuses, stratified according to geomorphology and exposure. We then tested if MPA networks designed to maximize habitat richness, diversity and rarity could also effectively maximize fish richness, diversity, and rarity. Effectiveness appeared highly sensitive to the fish census design itself, in relation to the type of habitat map used and the scale of analysis. Spatial distribution of habitats (estimator surrogate's distribution, quantity and location of fish census stations (target surrogate's sampling, and random processes in the MPA design all affected effectiveness to the point that one small change in the data set could lead to opposite conclusions. We suggest that previous conclusions on surrogacy effectiveness, either positive or negative, marine or terrestrial, should be considered with caution, except in instances where very dense data sets were used without pseudo-replication. Although this does not rule out the validity of using surrogates of species lists for conservation planning, the critical joint examination of both target and estimator

  12. Turbidity as a factor in the decline of Great Lakes fishes with special reference to Lake Erie

    Science.gov (United States)

    Van Oosten, John

    1948-01-01

    Fish live and thrive in water with turbidities that range above 400 p.p.m. and average 200 p.p.m. The waters of the Great Lakes usually are clear except in Lake Erie where the turbidities of the inshore areas averaged 37 p.p.m.; the turbidities of the offshore waters averaged less. Lake Erie waters were no clearer 50 years ago than they are now. In fact, the turbidity values are less now than they were in the earlier years; the annual average of the inshore waters dropped from 44 p.p.m. before 1930 to 32 p.p.m. in 1930 and later, and the April-May values decreased from 72 p.p.m. to 46 p.p.m. Any general decline in the Lake Erie fishes cannot be attributed to increased turbidities. Furthermore, these turbidities averaged well below 100 p.p.m. and, therefore, were too low to affect fishes adversely.

  13. Age-dependent dose factors and dose limits of annual radioactivity uptake with unsealed radioactive substances by occupationally exposed persons

    International Nuclear Information System (INIS)

    Kaul, A.; Nosske, D; Elsasser, U; Roedler, H.D.; Henrichs, K.

    1986-01-01

    The dose factors have been calculated on the basis of the ICRP models for dosimetric and metabolistic assessment, and are laid open in accordance with Annex XI ( to sec. 45 sub-section (2)) of the amended version of the Radiation Protection Ordinance. The contribution in hand explains the scientific fundamentals and results of the calculations of dose factors relating to inhalation and ingestion of unsealed radioactive substances by adult reference man, and age-dependent factors calculated for children and adolescents. Further, annual limits of uptake by occupationally exposed persons, as calculated on the basis of primary dose limits pursunant to the draft amendment presented by the Federal Interior Minister, are compared with relevant data given by the ICRP and EC institutions. (orig./DG) [de

  14. Role of maternally derived immunity in fish.

    Science.gov (United States)

    Swain, P; Nayak, S K

    2009-08-01

    Maternal immunity is of paramount importance for protection of young ones at early stage of life since the immune factors of an immunocompetent female are transferred transplacentally or through colostrum, milk or yolk to an immunologically naive neonate. Both innate and adaptive type of immunity are transferred of from mother to offspring in fishes. These factors include immunoglobulin (Ig)/antibody, complement factors, lysozymes, protease inhibitors like alpha macroglobulin, different types of lectins and serine proteases like molecules. Among different types of Ig viz. IgM, IgD, IgT/IgZ and IgM-IgZ chimera types, IgM is present in most of the teleostean fishes. In teleosts, IgM either as a reduced/breakdown product or monomeric form is usually transferred to the offsprings. The maternally derived IgM usually persists for a limited duration, exhausts within the completion of yolk absorption process, and completely disappears thereafter during larval stages. Maternal transfer of immunity which provides defense to embryo and larvae depends upon the health as well as the immune status of brood fish. The overall health status of brood fish can affect breeding performances, quality seed production and protection of offsprings. However, factors such as age, maturation, reproductive behaviour and nutrition (micro and macro-nutrients) may affect the immunity in brood fishes. Besides these, seasonal changes such as photoperiods, temperature, adverse environmental conditions, and stress conditions like handling, crowding, and water pollution/contamination can also affect the immunity of brood fishes. The maintenance of the brood stock immunity at high level during vitellogenesis and oogenesis, is utmost important for reducing mortalities at larval/post larval stages through maximum/optimum transfer of maternal immunity. Brood stock immunization prior to breeding as well as selective breeding among the disease resistant families might be the ideal criteria for producing

  15. Leptin stimulates hepatic growth hormone receptor and insulin-like growth factor gene expression in a teleost fish, the hybrid striped bass.

    Science.gov (United States)

    Won, Eugene T; Douros, Jonathan D; Hurt, David A; Borski, Russell J

    2016-04-01

    Leptin is an anorexigenic peptide hormone that circulates as an indicator of adiposity in mammals, and functions to maintain energy homeostasis by balancing feeding and energy expenditure. In fish, leptin tends to be predominantly expressed in the liver, another important energy storing tissue, rather than in fat depots as it is in mammals. The liver also produces the majority of circulating insulin-like growth factors (IGFs), which comprise the mitogenic component of the growth hormone (GH)-IGF endocrine growth axis. Based on similar regulatory patterns of leptin and IGFs that we have documented in previous studies on hybrid striped bass (HSB: Morone saxatilis×Morone chrysops), and considering the co-localization of these peptides in the liver, we hypothesized that leptin might regulate the endocrine growth axis in a manner that helps coordinate somatic growth with energy availability. Using a HSB hepatocyte culture system to simulate autocrine or paracrine exposure that might occur within the liver, this study examines the potential for leptin to modulate metabolism and growth through regulation of IGF gene expression directly, or indirectly through the regulation of GH receptors (GHR), which mediate GH-induced IGF expression. First, we verified that GH (50nM) has a classical stimulatory effect on IGF-1 and additionally show it stimulates IGF-2 transcription in hepatocytes. Leptin (5 and/or 50nM) directly stimulated in vitro GHR2 gene expression within 8h of exposure, and both GHR1 and GHR2 as well as IGF-1 and IGF-2 gene expression after 24h. Cells were then co-incubated with submaximal concentrations of leptin and GH (25nM each) to test if they had a synergistic effect on IGF gene expression, possibly through increased GH sensitivity following GHR upregulation by leptin. In combination, however, the treatments only had an additive effect on stimulating IGF-1 mRNA despite their capacity to increase GHR mRNA abundance. This suggests that leptin's stimulatory

  16. Low supply or core labour like limit factor of the growth the factory

    Directory of Open Access Journals (Sweden)

    Jiří Luňáček

    2013-11-01

    Full Text Available All companies act under the impact of allocation of manufacturing factors. Despite noticeable modernisation and automation of manufacturing processes, human labour still remains an indispensable manufacturing factor. At present, some industries face a low labour supply. Theoretical economics sees several possibilities of eliminating such facts. They can be modelled on the choice of a suitable company that is affected by such facts. In order to eliminate these unfavourable facts, the company has a chance to focus on a change in its strategy. This consists in changes of wage rates.

  17. Factors That May Tend to Limit the Religious Education of Recruits

    Science.gov (United States)

    1992-05-01

    chaplains also mentioned the following as tending to limit recruit religious education : (1) a lack of adequate chapel facilities , (2) not enough chaplains...inadequate chapel facilities at Recruit Training Command for recruit worship and religious education . This is a particular concern for the Catholic and... education . Procedures Data was gathered by distributing questionnaires to members of Division Six on October 22-23, 1991. Participation was voluntary

  18. Off-shell form factors in the soft photon limit for pion photoproduction

    International Nuclear Information System (INIS)

    Chumbalov, A.A.; Kamalov, S.S.

    1991-01-01

    The low energy theorems for the pion photoproduction are considered on the basis of the Adler-Dothan procedure. It is shown that the soft photon limit necessarily leads to the Born approximation for the π 0 -photoproduction amplitude at the threshold. All additional terms, according to the Adler-Dothan recipe, are to be neglected in the derivation of the LET. 5 refs.; 2 figs

  19. Physics of Limiting Phenomena in Superconducting Microwave Resonators: Vortex Dissipation, Ultimate Quench and Quality Factor Degradation Mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Checchin, Mattia [Illinois Inst. of Technology, Chicago, IL (United States)

    2016-12-01

    Superconducting niobium accelerating cavities are devices operating in radio-frequency and able to accelerate charged particles up to energy of tera-electron-volts. Such accelerating structures are though limited in terms of quality factor and accelerating gradient, that translates--in some cases--in higher capital costs of construction and operation of superconducting rf accelerators. Looking forward for a new generation of more affordable accelerators, the physical description of limiting mechanisms in superconducting microwave resonators is discussed. In particular, the physics behind the dissipation introduced by vortices in the superconductor, the ultimate quench limitations and the quality factor degradation mechanism after a quench are described in detail. One of the limiting factor of the quality factor is the dissipation introduced by trapped magnetic flux vortices. The radio-frequency complex response of trapped vortices in superconductors is derived by solving the motion equation for a magnetic flux line, assuming a bi-dimensional and mean free path-dependent Lorentzian-shaped pinning potential. The resulting surface resistance shows the bell-shaped trend as a function of the mean free path, in agreement with the experimental data observed. Such bell-shaped trend of the surface resistance is described in terms of the interplay of the two limiting regimes identified as pinning and flux flow regimes, for low and large mean free path values respectively. The model predicts that the dissipation regime--pinning- or flux-flow-dominated--can be tuned either by acting on the frequency or on the electron mean free path value. The effect of different configurations of pinning sites and strength on the vortex surface resistance are also discussed. Accelerating cavities are also limited by the quench of the superconductive state, which limits the maximum accelerating gradient achievable. The accelerating field limiting factor is usually associate d to the

  20. Physics of limiting phenomena in superconducting microwave resonators: Vortex dissipation, ultimate quench and quality factor degradation mechanisms

    Science.gov (United States)

    Checchin, Mattia

    Superconducting niobium accelerating cavities are devices operating in radiofrequency and able to accelerate charged particles up to energy of tera-electron-volts. Such accelerating structures are though limited in terms of quality factor and accelerating gradient, that translates--in some cases--in higher capital costs of construction and operation of superconducting rf accelerators. Looking forward for a new generation of more affordable accelerators, the physical description of limiting mechanisms in superconducting microwave resonators is discussed. In particular, the physics behind the dissipation introduced by vortices in the superconductor, the ultimate quench limitations and the quality factor degradation mechanism after a quench are described in detail. One of the limiting factor of the quality factor is the dissipation introduced by trapped magnetic flux vortices. The radio-frequency complex response of trapped vortices in superconductors is derived by solving the motion equation for a magnetic flux line, assuming a bi-dimensional and mean free path-dependent Lorentzian-shaped pinning potential. The resulting surface resistance shows the bell-shaped trend as a function of the mean free path, in agreement with the experimental data observed. Such bell-shaped trend of the surface resistance is described in terms of the interplay of the two limiting regimes identified as pinning and flux flow regimes, for low and large mean free path values respectively. The model predicts that the dissipation regime--pinning- or flux-flow-dominated--can be tuned either by acting on the frequency or on the electron mean free path value. The effect of different configurations of pinning sites and strength on the vortex surface resistance are also discussed. Accelerating cavities are also limited by the quench of the superconductive state, which limits the maximum accelerating gradient achievable. The accelerating field limiting factor is usually associated to the superheating

  1. Perceived barriers to consumption of fish among Norwegian women.

    Science.gov (United States)

    Trondsen, Torbjørn; Scholderer, Joachim; Lund, Eiliv; Eggen, Anne E

    2003-12-01

    This study aimed to characterize constraints on consumption of fish perceived by consumers in Norway. A random sample of Norwegian women aged 45-69 years answered a self-administered mail questionnaire in 1996 about eating habits, perceived barriers to fish consumption, socioeconomic status, and questions related to health. Altogether, 9407 women answered the questionnaire (response rate: 52.5%). Data were analyzed by means of logistic regression. Limited supply of fish products that satisfy children's wishes reduce at-home fish consumption. People with health problems and those who wish to lose weight are dissatisfied with the range of products offered in the marketplace. Satisfaction with quality and availability of wild lean codfish, especially in inland regions, is lower than for aqua-cultured fat salmon. Neither income nor education or health factors were significantly associated with consumption levels among those who would like to eat more fish. Higher education and income were associated with increased dissatisfaction about fish consumption, but also with reduced perception of most barriers. It is concluded that improvements in the supply of high-quality fresh and processed fish products that satisfy (a) children's wishes, (b) health-oriented family members, and (c) convenience-oriented consumers, will significantly increase at-home consumption of fish.

  2. Anatomy of a bottleneck: diagnosing factors limiting population growth in the Puerto Rican Parrot

    Science.gov (United States)

    S.R. Beissinger; Jr Wunderle; J.M. Meyers; B.E. Saether; S. Engen

    2008-01-01

    The relative importance of genetic, demographic, environmental, and catastrophic processes that maintain population bottlenecks has received little consideration. We evaluate the role of these factors in maintaining the Puerto Rican Parrot (Amazona vittata) in a prolonged bottleneck from 1973 through 2000 despite intensive conservation efforts. We first conduct a risk...

  3. Pushing the limits of excited-state g-factor measurements

    Science.gov (United States)

    Stuchbery, Andrew E.; McCormick, Brendan P.; Gray, Timothy J.; Coombes, Ben J.

    2018-05-01

    Current developments in excited-state g-factor measurements are discussed with an emphasis on cases where the experimental methodology is being extended into new regimes. The transient-field technique, the recoil in vacuum method, and moment measurements with LaBr3 detectors are discussed.

  4. Late presentation for HIV care in central Haiti: factors limiting access to care.

    Science.gov (United States)

    Louis, C; Ivers, L C; Smith Fawzi, M C; Freedberg, K A; Castro, A

    2007-04-01

    Many patients with HIV infection present for care late in the course of their disease, a factor which is associated with poor prognosis. Our objective was to identify factors associated with late presentation for HIV care among patients in central Haiti. Thirty-one HIV-positive adults, approximately 10% of the HIV-infected population followed at a central Haiti hospital, participated in this research study. A two-part research tool that included a structured questionnaire and an ethnographic life history interview was used to collect quantitative as well as qualitative data about demographic factors related to presentation for HIV care. Sixty-five percent of the patients in this study presented late for HIV care, as defined by CD4 cell count below 350 cells/mm3. Factors associated with late presentation included male sex, older age, patient belief that symptoms are not caused by a medical condition, greater distance from the medical clinic, lack of prior access to effective medical care, previous requirement to pay for medical care, and prior negative experience at local hospitals. Harsh poverty was a striking theme among all patients interviewed. Delays in presentation for HIV care in rural Haiti are linked to demographic, socioeconomic and structural factors, many of which are rooted in poverty. These data suggest that a multifaceted approach is needed to overcome barriers to early presentation for care. This approach might include poverty alleviation strategies; provision of effective, reliable and free medical care; patient outreach through community health workers and collaboration with traditional healers.

  5. Risky sexual behavior among rural female adolescents in Malaysia: a limited role of protective factors.

    Science.gov (United States)

    Ahmadian, Maryam; Hamsan, Hanina H; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

    2014-03-23

    This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, and knowledge and attitudes about sexuality were considered in risky sexual behaviors in rural Malay girls. The effects of other covariates for premarital sexual intercourse were controlled by logistic regression model. Of the 770 rural female students, about 3.2% of respondents reported experience of sexual intercourse in the past three months. Out of those sexually active girls, 36% were 17 years old and 20% stated having sexual intercourse with more than one partner, and 72% did not use contraception during the most recent sexual intercourse. Midnight activities, peer-sexual disorder, self-evaluation, and attitude toward sexual health were significant predictors of sexual intercourse in rural girls in Malaysia. The finding highlights the impact of psychological factors and peer group influences on the challenges of premarital sexual behavior among rural girls and the notion of school-based sexual health education for adolescents. This study triggers other researchers take into account a comprehensive view of protective factors operating in adolescents' risky sexual behaviors in Asian culture seeing that family domain variables, unexpectedly, exerted no predicting influence on sexually active female teens in rural areas in Malaysia.

  6. Risky Sexual Behavior among Rural Female Adolescents in Malaysia: A Limited Role of Protective Factors

    Science.gov (United States)

    Ahmadian, Maryam; Hamsan, Hanina H.; Abdullah, Haslinda; Samah, Asnarulkhadi Abu; Noor, Amna Md

    2014-01-01

    Purpose: This paper presents the findings of a cross-sectional survey on the risk and protective factors of premarital sexual behavior among rural female adolescents in Peninsular Malaysia. Methods: We investigated data on 770 female respondents aged 13-17 years in rural areas to identify predictive factors for premarital sexual intercourse. Data were analyzed using bivariate and multivariate regression. Specific socio-demographic factors, psychological and family domains, peer delinquency, and knowledge and attitudes about sexuality were considered in risky sexual behaviors in rural Malay girls. The effects of other covariates for premarital sexual intercourse were controlled by logistic regression model. Results: Of the 770 rural female students, about 3.2% of respondents reported experience of sexual intercourse in the past three months. Out of those sexually active girls, 36% were 17 years old and 20% stated having sexual intercourse with more than one partner, and 72% did not use contraception during the most recent sexual intercourse. Midnight activities, peer-sexual disorder, self-evaluation, and attitude toward sexual health were significant predictors of sexual intercourse in rural girls in Malaysia. Conclusion: The finding highlights the impact of psychological factors and peer group influences on the challenges of premarital sexual behavior among rural girls and the notion of school-based sexual health education for adolescents. This study triggers other researchers take into account a comprehensive view of protective factors operating in adolescents’ risky sexual behaviors in Asian culture seeing that family domain variables, unexpectedly, exerted no predicting influence on sexually active female teens in rural areas in Malaysia. PMID:24762359

  7. Anadromous fish behaviour important for fish passage

    International Nuclear Information System (INIS)

    Kynard, B.E.

    1993-01-01

    An understanding of the behavior of target fish species is necessary for proper design, location, and operation of a successful upstream or downstream fishway for anadromous migrants. Important fish behaviors are seasonal and daily timing of migration; rheotaxis and near field behavior; stimulus-response behavior; swimming capability; shoaling behavior; response to physical environmental factors such as illumination, sound, water depth, current velocity, and structure; response to chemicals; and response to biological factors such as competition for space and response to predators. The information on migrant fish behavior is reviewed, using examples from the literature on the behavior of eastern anadromous species, particularly Atlantic salmon (Salmo salar) and American shad (Alosa sapidissima). 87 refs

  8. Factors that contribute to physician variability in decisions to limit life support in the ICU: a qualitative study.

    Science.gov (United States)

    Wilson, Michael E; Rhudy, Lori M; Ballinger, Beth A; Tescher, Ann N; Pickering, Brian W; Gajic, Ognjen

    2013-06-01

    Our aim was to explore reasons for physician variability in decisions to limit life support in the intensive care unit (ICU) utilizing qualitative methodology. Single center study consisting of semi-structured interviews with experienced physicians and nurses. Seventeen intensivists from medical (n = 7), surgical (n = 5), and anesthesia (n = 5) critical care backgrounds, and ten nurses from medical (n = 5) and surgical (n = 5) ICU backgrounds were interviewed. Principles of grounded theory were used to analyze the interview transcripts. Eleven factors within four categories were identified that influenced physician variability in decisions to limit life support: (1) physician work environment-workload and competing priorities, shift changes and handoffs, and incorporation of nursing input; (2) physician experiences-of unexpected patient survival, and of limiting life support in physician's family; (3) physician attitudes-investment in a good surgical outcome, specialty perspective, values and beliefs; and (4) physician relationship with patient and family-hearing the patient's wishes firsthand, engagement in family communication, and family negotiation. We identified several factors which physicians and nurses perceived were important sources of physician variability in decisions to limit life support. Ways to raise awareness and ameliorate the potentially adverse effects of factors such as workload, competing priorities, shift changes, and handoffs should be explored. Exposing intensivists to long term patient outcomes, formalizing nursing input, providing additional training, and emphasizing firsthand knowledge of patient wishes may improve decision making.

  9. Factors limiting the implementation of mechanical harvesting of sugarcane in Campos dos Goytacazes, RJ, Brazil

    Directory of Open Access Journals (Sweden)

    Cristóbal Soto Solano

    Full Text Available ABSTRACT The objective of this research was to identify and characterize the main technical factors that affect the deployment of the mechanized harvesting of sugarcane in Campos dos Goytacazes, Rio de Janeiro, Brazil. In general, it can be stated there were restrictive factors related to machinery, administrative management, and technical planning. We identified significant technical restrictions in the planting system, particularly in relation to the size and shape of the plots, length of the rows, row spacing, and inadequate varieties. For efficient use of mechanized harvesting, a technical planning is necessary with changes in the cropping system, adopting wider and more uniform plots regarding to its format, with rows over 500 m length and row spacing of 1.50 m and upright, productive, and deep-rooted varieties.

  10. Theory of factors limiting high gradient operation of warm accelerating structures

    Energy Technology Data Exchange (ETDEWEB)

    Nusinovich, Gregory S. [Univ. of Maryland, College Park, MD (United States)

    2014-07-22

    This report consists of two parts. In the first part we describe a study of the heating of microprotrusions on surfaces of accelerating structures. This ;process is believed to lead to breakdown in these structures. Our study revealed that for current accelerator parameters melting should not occur due to space charge limitations of the current emitted by a protrusion. The second part describes a novel concept to develop THz range sources based on harmonic cyclotron masers for driving future colliders. This work was stimulated by a recent request of SLAC to develop high power, high-efficiency sources of sub-THz radiation for future high-gradient accelerators.

  11. HSL MI28: An Efficient and Robust Limited-Memory Incomplete Cholesky Factorization Code

    Czech Academy of Sciences Publication Activity Database

    Scott, J.; Tůma, Miroslav

    2014-01-01

    Roč. 40, č. 4 (2014), Article number 24 ISSN 0098-3500 R&D Projects: GA ČR GA13-06684S Grant - others:EPSRC(GB) EP/I013067/1 Institutional support: RVO:67985807 Keywords : preconditioning * sparse linear systems * incomplete decompositions * preconditioned iterative methods Subject RIV: IN - Informatics, Computer Science Impact factor: 1.863, year: 2014

  12. HSL MI28: An Efficient and Robust Limited-Memory Incomplete Cholesky Factorization Code

    Czech Academy of Sciences Publication Activity Database

    Scott, J.; Tůma, Miroslav

    2014-01-01

    Roč. 40, č. 4 (2014), Art icle number 24 ISSN 0098-3500 R&D Projects: GA ČR GA13-06684S Grant - others:EPSRC(GB) EP/I013067/1 Institutional support: RVO:67985807 Keywords : preconditioning * sparse linear systems * incomplete decompositions * preconditioned iterative methods Subject RIV: IN - Informatics, Computer Science Impact factor: 1.863, year: 2014

  13. Hepatocyte growth factor limits autoimmune neuroinflammation via glucocorticoid-induced leucine zipper expression in dendritic cells.

    Science.gov (United States)

    Benkhoucha, Mahdia; Molnarfi, Nicolas; Dunand-Sauthier, Isabelle; Merkler, Doron; Schneiter, Gregory; Bruscoli, Stefano; Riccardi, Carlo; Tabata, Yasuhiko; Funakoshi, Hiroshi; Nakamura, Toshikazu; Reith, Walter; Santiago-Raber, Marie-Laure; Lalive, Patrice H

    2014-09-15

    Autoimmune neuroinflammation, including multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), a prototype for T cell-mediated autoimmunity, is believed to result from immune tolerance dysfunction leading to demyelination and substantial neurodegeneration. We previously showed that CNS-restricted expression of hepatocyte growth factor (HGF), a potent neuroprotective factor, reduced CNS inflammation and clinical deficits associated with EAE. In this study, we demonstrate that systemic HGF treatment ameliorates EAE through the development of tolerogenic dendritic cells (DCs) with high expression levels of glucocorticoid-induced leucine zipper (GILZ), a transcriptional repressor of gene expression and a key endogenous regulator of the inflammatory response. RNA interference-directed neutralization of GILZ expression by DCs suppressed the induction of tolerance caused by HGF. Finally, adoptive transfer of HGF-treated DCs from wild-type but not GILZ gene-deficient mice potently mediated functional recovery in recipient mice with established EAE through effective modulation of autoaggressive T cell responses. Altogether, these results show that by inducing GILZ in DCs, HGF reproduces the mechanism of immune regulation induced by potent immunomodulatory factors such as IL-10, TGF-β1, and glucocorticoids and therefore that HGF therapy may have potential in the treatment of autoimmune dysfunctions. Copyright © 2014 by The American Association of Immunologists, Inc.

  14. Linking spawning ground extent to environmental factors - patterns and dispersal during the egg phase of four North Sea fishes

    DEFF Research Database (Denmark)

    Höffle, Hannes; van Damme, Cindy J. G.; Fox, Clive J.

    2018-01-01

    , the location of the spawning grounds appeared stable on the broad scale but centres of egg abundance varied between the surveyed years. Potential effects of long-term climate change and anthropogenic short-term disturbances, such as seismic surveys, on fish reproduction are discussed, pointing out the demand...... surveys in 2004 and 2009, the present study uses Generalized Additive Mixed Models (GAMMs) to delimit these spawning grounds using the distribution of recently spawned eggs, investigates their relationship to specific environmental conditions and examines egg dispersal during their development. Results...

  15. Fish Rhabdoviruses

    Science.gov (United States)

    Kurath, G.; Winton, J.

    2008-01-01

    Many important viral pathogens of fish are members of the family Rhabdoviridae. The viruses in this large group cause significant losses in populations of wild fish as well as among fish reared in aquaculture. Fish rhabdoviruses often have a wide host and geographic range, and infect aquatic animals in both freshwater and seawater. The fish rhabdoviruses comprise a diverse collection of isolates that can be placed in one of two quite different groups: isolates that are members of the established genusNovirhabdovirus, and those that are most similar to members of the genus Vesiculovirus. Because the diseases caused by fish rhabdoviruses are important to aquaculture, diagnostic methods for their detection and identification are well established. In addition to regulations designed to reduce the spread of fish viruses, a significant body of research has addressed methods for the control or prevention of diseases caused by fish rhabdoviruses, including vaccination. The number of reported fish rhabdoviruses continues to grow as a result of the expansion of aquaculture, the increase in global trade, the development of improved diagnostic methods, and heightened surveillance activities. Fish rhabdoviruses serve as useful components of model systems to study vertebrate virus disease, epidemiology, and immunology.

  16. Factors limiting the domestic density of Triatoma infestans in north-west Argentina: a longitudinal study.

    Science.gov (United States)

    Cecere, M C; Gürtler, R E; Chuit, R; Cohen, J E

    1998-01-01

    Reported are the environmental and demographic risk factors associated with the domestic infestation and density of Triatoma infestans in three heavily infested rural villages in Santiago del Estero Province, Argentina. In a one-factor unadjusted analysis, the number of T. infestans captured per person-hour was associated significantly and negatively with the use of domestic insecticides by householders, type of thatch used in the roofs and the age of the house; and positively with the following: degree of cracking of the indoor walls and presence of hens nesting indoors. In one model, using multiple linear regression and a backward stepwise elimination procedure, most of the variation in the overall abundance of T. infestans was explained by insecticide use and the presence of hens nesting indoors; in another model using the same procedure it was explained by insecticide use, bug density in 1988 and previous spraying with deltamethrin in 1985. Variations in bug density per capture stratum (household goods, beds, walls and roof) were explained by the bug density in other strata and by one or two of the following risk factors: hens nesting indoors, type of roof, presence of cracks in the walls and number of people living in the house. Bug density might be locally controlled by the availability of refuges in the roofs and walls, by the presence of hens nesting indoors and by the use of domestic insecticides. Certain local materials, such as a grass known as simbol, could be successfully used in rural housing improvement programmes aimed at reducing the availability of refuges for insects in the roof.

  17. 50 CFR 622.38 - Landing fish intact.

    Science.gov (United States)

    2010-10-01

    ... that is operating under the respective trip limits. Such cut-off fish also may be sold. A maximum of... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Landing fish intact. 622.38 Section 622.38... Landing fish intact. The operator of a vessel that fishes in the EEZ is responsible for ensuring that fish...

  18. Investigation on the Quality Factor Limit of the (111 Silicon Based Disk Resonator

    Directory of Open Access Journals (Sweden)

    Xin Zhou

    2018-01-01

    Full Text Available Quality factor is one of the most important parameters for a MEMS resonator. Most MEMS resonators are dominated by thermoelastic dissipation (TED. This paper demonstrates that the TED in a disk resonator that is made of (111 single-crystal silicon is surpassed by clamping loss. The stiffness-mass decoupling design method, combined with reducing the beam width, was used to engineer high QTED. Experiments show that Q of the (111 disk resonator have an upper boundary that is determined by the clamping loss caused by the unbalanced out-of-plane displacement. The origin of the out-of-plane displacement is explained by theory and simulation.

  19. Factors limiting vocal-tract length discrimination in cochlear implant simulations.

    Science.gov (United States)

    Gaudrain, Etienne; Başkent, Deniz

    2015-03-01

    Perception of voice characteristics allows normal hearing listeners to identify the gender of a speaker, and to better segregate speakers from each other in cocktail party situations. This benefit is largely driven by the perception of two vocal characteristics of the speaker: The fundamental frequency (F0) and the vocal-tract length (VTL). Previous studies have suggested that cochlear implant (CI) users have difficulties in perceiving these cues. The aim of the present study was to investigate possible causes for limited sensitivity to VTL differences in CI users. Different acoustic simulations of CI stimulation were implemented to characterize the role of spectral resolution on VTL, both in terms of number of channels and amount of channel interaction. The results indicate that with 12 channels, channel interaction caused by current spread is likely to prevent CI users from perceiving VTL differences typically found between male and female speakers.

  20. Continuum limit of the leading order HQET form factor in B{sub s}→Klν decays

    Energy Technology Data Exchange (ETDEWEB)

    Bahr, Felix; Banerjee, Debasish; Koren, Mateusz; Simma, Hubert; Sommer, Rainer [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Bernardoni, Fabio [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Technische Univ. Dresden (Germany). Medizinische Fakultaet ' ' Carl Gustav Carus' ' ; Joseph, Anosh [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics (DAMTP); Collaboration: ALPHA Collaboration

    2016-01-15

    We discuss the computation of form factors for semi-leptonic decays of B-, B{sub s}- mesons in lattice QCD. Considering in particular the example of the static B{sub s} form factors we demonstrate that after non-perturbative renormalization the continuum limit can be taken with confidence. The resulting precision is of interest for extractions of V{sub ub}. The size of the corrections of order 1/m{sub b} is just estimated at present but it is expected that their inclusion does not pose significant difficulties.

  1. The Transcription Factor STAT6 Mediates Direct Repression of Inflammatory Enhancers and Limits Activation of Alternatively Polarized Macrophages

    OpenAIRE

    Czimmerer, Zsolt; Daniel, Bence; Horvath, Attila; Rückerl, Dominik; Nagy, Gergely; Kiss, Mate; Peloquin, Matthew; Budai, Marietta M.; Cuaranta-Monroy, Ixchelt; Simandi, Zoltan; Steiner, Laszlo; Nagy, Bela; Poliska, Szilard; Banko, Csaba; Bacso, Zsolt

    2018-01-01

    Summary The molecular basis of signal-dependent transcriptional activation has been extensively studied in macrophage polarization, but our understanding remains limited regarding the molecular determinants of repression. Here we show that IL-4-activated STAT6 transcription factor is required for the direct transcriptional repression of a large number of genes during in vitro and in vivo alternative macrophage polarization. Repression results in decreased lineage-determining transcription fac...

  2. [Factors limiting distribution of the rare lichen species Lobaria pulmonaria (in forests of the Kologriv Forest Nature Reserve)].

    Science.gov (United States)

    Ivanova, N V

    2015-01-01

    The distribution patterns and coenotic confines ofthe epiphytic lichen Lobaria pulmonaria have been studied. The factors limiting the habitat of this rare lichen species in the Kologriv Forest Nature Reserve (southern taiga subzone) have been revealed. It has been shown that L. pulmonaria is attracted to forest areas, which are less affected by humans and characterized by better light conditions than other communities. It has been found that L. pulmonaria is able to colonize trees at various ontogenetic states, beginning from virginal ones.

  3. Limited clinical efficacy of azacitidine in transfusion-dependent, growth factor-resistant, low- and Int-1-risk MDS

    DEFF Research Database (Denmark)

    Holm, Mette; Dybedahl, I; Holm, Mette

    2014-01-01

    This prospective phase II study evaluated the efficacy of azacitidine (Aza)+erythropoietin (Epo) in transfusion-dependent patients with lower-risk myelodysplastic syndrome (MDS). Patients ineligible for or refractory to full-dose Epo+granulocyte colony stimulation factors for >8 weeks and a trans...... patients, but efficacy is limited, toxicity substantial and most responses of short duration. This treatment cannot be generally recommended in lower-risk MDS. Mutational screening revealed a high frequency of mutations....

  4. A measurement of the QCD colour factors and a limit on the light gluino

    CERN Document Server

    Barate, R; Décamp, D; Ghez, P; Goy, C; Lees, J P; Lucotte, A; Minard, M N; Nief, J Y; Odier, P; Pietrzyk, B; Casado, M P; Chmeissani, M; Comas, P; Crespo, J M; Delfino, M C; Fernández, E; Fernández-Bosman, M; Garrido, L; Juste, A; Martínez, M; Miquel, R; Mir, L M; Orteu, S; Padilla, C; Park, I C; Pascual, A; Perlas, J A; Riu, I; Sánchez, F; Teubert, F; Colaleo, A; Creanza, D; De Palma, M; Gelao, G; Iaselli, Giuseppe; Maggi, G; Maggi, M; Marinelli, N; Nuzzo, S; Ranieri, A; Raso, G; Ruggieri, F; Selvaggi, G; Silvestris, L; Tempesta, P; Tricomi, A; Zito, G; Huang, X; Lin, J; Ouyang, Q; Wang, T; Xie, Y; Xu, R; Xue, S; Zhang, J; Zhang, L; Zhao, W; Abbaneo, D; Alemany, R; Bazarko, A O; Bright-Thomas, P G; Cattaneo, M; Cerutti, F; Drevermann, H; Forty, Roger W; Frank, M; Hagelberg, R; Harvey, J; Janot, P; Jost, B; Kneringer, E; Knobloch, J; Lehraus, Ivan; Lutters, G; Mato, P; Minten, Adolf G; Moneta, L; Pacheco, A; Pusztaszeri, J F; Ranjard, F; Rensing, P E; Rizzo, G; Rolandi, Luigi; Schlatter, W D; Schmelling, M; Schmitt, M; Schneider, O; Tejessy, W; Tomalin, I R; Wachsmuth, H W; Wagner, A; Ajaltouni, Ziad J; Barrès, A; Boyer, C; Falvard, A; Ferdi, C; Gay, P; Guicheney, C; Henrard, P; Jousset, J; Michel, B; Monteil, S; Montret, J C; Pallin, D; Perret, P; Podlyski, F; Proriol, J; Rosnet, P; Rossignol, J M; Fearnley, Tom; Hansen, J B; Hansen, J D; Hansen, J R; Hansen, P H; Nilsson, B S; Rensch, B; Wäänänen, A; Daskalakis, G; Kyriakis, A; Markou, C; Simopoulou, Errietta; Siotis, I; Vayaki, Anna; Zachariadou, K; Blondel, A; Bonneaud, G R; Brient, J C; Bourdon, P; Rougé, A; Rumpf, M; Valassi, Andrea; Verderi, M; Videau, H L; Candlin, D J; Parsons, M I; Focardi, E; Parrini, G; Corden, M; Georgiopoulos, C H; Jaffe, D E; Antonelli, A; Bencivenni, G; Bologna, G; Bossi, F; Campana, P; Capon, G; Casper, David William; Chiarella, V; Felici, G; Laurelli, P; Mannocchi, G; Murtas, F; Murtas, G P; Passalacqua, L; Pepé-Altarelli, M; Curtis, L; Dorris, S J; Halley, A W; Knowles, I G; Lynch, J G; O'Shea, V; Raine, C; Scarr, J M; Smith, K; Teixeira-Dias, P; Thompson, A S; Thomson, E; Thomson, F; Turnbull, R M; Becker, U; Geweniger, C; Graefe, G; Hanke, P; Hansper, G; Hepp, V; Kluge, E E; Putzer, A; Schmidt, M; Sommer, J; Tittel, K; Werner, S; Wunsch, M; Beuselinck, R; Binnie, David M; Cameron, W; Dornan, Peter J; Girone, M; Goodsir, S M; Martin, E B; Moutoussi, A; Nash, J; Sedgbeer, J K; Stacey, A M; Williams, M D; Dissertori, G; Girtler, P; Kuhn, D; Rudolph, G; Betteridge, A P; Bowdery, C K; Colrain, P; Crawford, G; Finch, A J; Foster, F; Hughes, G; Sloan, Terence; Williams, M I; Galla, A; Giehl, I; Greene, A M; Hoffmann, C; Jakobs, K; Kleinknecht, K; Quast, G; Renk, B; Rohne, E; Sander, H G; Van Gemmeren, P; Zeitnitz, C; Aubert, Jean-Jacques; Benchouk, C; Bonissent, A; Bujosa, G; Calvet, D; Carr, J; Coyle, P; Diaconu, C A; Etienne, F; Konstantinidis, N P; Leroy, O; Payre, P; Rousseau, D; Talby, M; Sadouki, A; Thulasidas, M; Trabelsi, K; Aleppo, M; Ragusa, F; Berlich, R; Blum, Walter; Büscher, V; Dietl, H; Dydak, Friedrich; Ganis, G; Gotzhein, C; Kroha, H; Lütjens, G; Lutz, Gerhard; Männer, W; Moser, H G; Richter, R H; Rosado-Schlosser, A; Schael, S; Settles, Ronald; Seywerd, H C J; Saint-Denis, R; Stenzel, H; Wiedenmann, W; Wolf, G; Boucrot, J; Callot, O; Chen, S; Choi, Y; Cordier, A; Davier, M; Duflot, L; Grivaz, J F; Heusse, A; Höcker, A; Jacholkowska, A; Jacquet, M; Kim, D W; Le Diberder, F R; Lefrançois, J; Lutz, A M; Nikolic, I A; Park, H J; Schune, M H; Simion, S; Veillet, J J; Videau, I; Zerwas, D; Azzurri, P; Bagliesi, G; Batignani, G; Bettarini, S; Bozzi, C; Calderini, G; Carpinelli, M; Ciocci, M A; Ciulli, V; Dell'Orso, R; Fantechi, R; Ferrante, I; Foà, L; Forti, F; Giassi, A; Giorgi, M A; Gregorio, A; Ligabue, F; Lusiani, A; Marrocchesi, P S; Messineo, A; Palla, Fabrizio; Sanguinetti, G; Sciabà, A; Spagnolo, P; Steinberger, Jack; Tenchini, Roberto; Tonelli, G; Vannini, C; Venturi, A; Verdini, P G; Blair, G A; Bryant, L M; Chambers, J T; Gao, Y; Green, M G; Medcalf, T; Perrodo, P; Strong, J A; Von Wimmersperg-Töller, J H; Botterill, David R; Clifft, R W; Edgecock, T R; Haywood, S; Maley, P; Norton, P R; Thompson, J C; Wright, A E; Bloch-Devaux, B; Colas, P; Emery, S; Kozanecki, Witold; Lançon, E; Lemaire, M C; Locci, E; Pérez, P; Rander, J; Renardy, J F; Roussarie, A; Schuller, J P; Schwindling, J; Trabelsi, A; Vallage, B; Black, S N; Dann, J H; Johnson, R P; Kim, H Y; Litke, A M; McNeil, M A; Taylor, G; Booth, C N; Boswell, R; Brew, C A J; Cartwright, S L; Combley, F; Kelly, M S; Lehto, M H; Newton, W M; Reeve, J; Thompson, L F; Böhrer, A; Brandt, S; Cowan, G D; Grupen, Claus; Saraiva, P; Smolik, L; Stephan, F; Apollonio, M; Bosisio, L; Della Marina, R; Giannini, G; Gobbo, B; Musolino, G; Rothberg, J E; Wasserbaech, S R; Armstrong, S R; Elmer, P; Feng, Z; Ferguson, D P S; Gao, Y S; González, S; Grahl, J; Greening, T C; Hayes, O J; Hu, H; McNamara, P A; Nachtman, J M; Orejudos, W; Pan, Y B; Saadi, Y; Scott, I J; Walsh, J; Wu Sau Lan; Wu, X; Yamartino, J M; Zheng, M; Zobernig, G

    1997-01-01

    Using data collected from 1992 to 1995 with the ALEPH detector at LEP, a measurement of the colour factor ratios CA/CF and TF/CF and the strong coupling constant $\\overline{\\alpha}_s = CF \\alpha_s(Mz)/ (2\\pi)$ has been performed by fitting theoretical predictions simultaneously to the measured differential two-jet rate and angular distributions in four-jet events. The result is found to be in excellent agreement with QCD, CA/CF = 2.20 +- 0.09 (stat) +- 0.13 (syst) , TF/CF = 0.29 +- 0.05 (stat) +- 0.06 (syst) . Fixing CA/CF$ and TF/CF to the QCD values permits a determination of $\\alpha_s(Mz)$ and nf, the number of active flavours. With this measurement the existence of a gluino with mass below 6.3 GeV/c^2 is excluded at 95% confidence level.

  5. Cdc6 is a rate-limiting factor for proliferative capacity during HL60 cell differentiation

    International Nuclear Information System (INIS)

    Barkley, Laura R.; Hong, Hye Kyung; Kingsbury, Sarah R.; James, Michelle; Stoeber, Kai; Williams, Gareth H.

    2007-01-01

    The DNA replication (or origin) licensing pathway represents a critical step in cell proliferation control downstream of growth signalling pathways. Repression of origin licensing through down-regulation of the MCM licensing factors (Mcm2-7) is emerging as a ubiquitous route for lowering proliferative capacity as metazoan cells exit the cell division cycle into quiescent, terminally differentiated and senescent 'out-of-cycle' states. Using the HL60 monocyte/macrophage differentiation model system and a cell-free DNA replication assay, we have undertaken direct biochemical investigations of the coupling of origin licensing to the differentiation process. Our data show that down-regulation of the MCM loading factor Cdc6 acts as a molecular switch that triggers loss of proliferative capacity during early engagement of the somatic differentiation programme. Consequently, addition of recombinant Cdc6 protein to in vitro replication reactions restores DNA replication competence in nuclei prepared from differentiating cells. Differentiating HL60 cells over-expressing either wild-type Cdc6 or a CDK phosphorylation-resistant Cdc6 mutant protein (Cdc6A4) exhibit an extended period of cell proliferation compared to mock-infected cells. Notably, differentiating HL60 cells over-expressing the Cdc6A4 mutant fail to down-regulate Cdc6 protein levels, suggesting that CDK phosphorylation of Cdc6 is linked to its down-regulation during differentiation and the concomitant decrease in cell proliferation. In this experimental model, Cdc6 therefore plays a key role in the sequential molecular events leading to repression of origin licensing and loss of proliferative capacity during execution of the differentiation programme

  6. Flavin as an Indicator of the Rate-Limiting Factor for Microbial Current Production in Shewanella oneidensis MR-1

    International Nuclear Information System (INIS)

    Saito, Junki; Hashimoto, Kazuhito; Okamoto, Akihiro

    2016-01-01

    Microbial electrode catalysis such as microbial fuel cells or electrosynthesis involves electron exchange with the electrodes located at the cell exterior; i.e., extracellular electron transport (EET). Despite the vast amount of research on the kinetics of EET to optimize the catalysis rate, the relevance of other factors, including upstream metabolic reactions, has scarcely been investigated. Herein, we report an in vivo electrochemical assay to confirm whether EET limits anodic current production (j) for the lactate oxidation of Shewanella oneidensis MR-1. Addition of riboflavin, which specifically enhances the EET rate, increased j only in the early phase before j saturation. In contrast, when we removed a trace metal ion necessary for upstream reactions from the electrolyte, a significant decrease in j and the lactate consumption rate was observed only after j saturation. These data suggest that the limiting factor for j shifted from EET to upstream reactions, highlighting the general importance of enhancing, for example, microbial metabolism, especially for long-standing practical applications. Our concept to specifically control the rate of EET could be applicable to other bioelectrode catalysis systems as a strategy to monitor their rate-limiting factors.

  7. Seasonal shift in climatic limiting factors on tree transpiration: evidence from sap flow observations at alpine treelines in southeast Tibet

    Directory of Open Access Journals (Sweden)

    Liu Xinsheng

    2016-07-01

    Full Text Available Alpine and northern treelines are primarily controlled by low temperatures. However, little is known about the impact of low soil temperature on tree transpiration at treelines. We aim to test the hypothesis that in cold-limited forests, the main limiting factors for tree transpiration switch from low soil temperature before summer solstice to atmospheric evaporative demand after summer solstice, which generally results in low transpiration in the early growing season. Sap flow, meteorological factors and predawn needle water potential were continuously monitored throughout one growing season across Smith fir (Abies georgei var. smithii and juniper (Juniperus saltuaria treelines in southeast Tibet. Sap flow started in early May and corresponded to a threshold mean air-temperature of 0 oC. Across tree species, transpiration was mainly limited by low soil temperature prior to the summer solstice but by vapor pressure deficit and solar radiation post-summer solstice, which was further confirmed on a daily scale. As a result, tree transpiration for both tree species was significantly reduced in the pre-summer solstice period as compared to post-summer solstice, resulting in a lower predawn needle water potential for Smith fir trees in the early growing season. Our data supported the hypothesis, suggesting that tree transpiration mainly responds to soil temperature variations in the early growing season. The results are important for understanding the hydrological response of cold-limited forest ecosystems to climate change.

  8. Attitude of Healthcare Professionals: A Major Limiting Factor in Organ Donation from Brain-Dead Donors

    Directory of Open Access Journals (Sweden)

    Maciej Kosieradzki

    2014-01-01

    Full Text Available Public attitude toward deceased donor organ recovery in Poland is quite positive, with only 15% opposing to donation of their own organs, yet actual donation rate is only 16/pmp. Moreover, donation rate varies greatly (from 5 to 28 pmp in different regions of the country. To identify the barriers of organ donation, we surveyed 587 physicians involved in brain death diagnosis from regions with low (LDR and high donation rates (HDR. Physicians from LDR were twice more reluctant to start diagnostic procedure when clinical signs of brain death were present (14% versus 5.5% physicians from HDR who would not diagnose death, resp.. Twenty-five percent of LDR physicians (as opposed to 12% of physicians from HDR would either continue with intensive therapy or confirm brain death and limit to the so-called minimal therapy. Only 32% of LDR physicians would proceed with brain death diagnosis regardless of organ donation, compared to 67% in HDR. When donation was not an option, mechanical ventilation would be continued more often in LDR regions (43% versus 26.7%; P<0.01. In conclusion, low donation activity seems to be mostly due to medical staff attitude.

  9. Exercise hyperthermia as a factor limiting physical performance - Temperature effect on muscle metabolism

    Science.gov (United States)

    Kozlowski, S.; Brzezinska, Z.; Kruk, B.; Kaciuba-Uscilko, H.; Greenleaf, J. E.

    1985-01-01

    The effect of trunk cooling on the muscle contents of ATP, ADP, AMP, creatine phosphate (CrP), and creatine, as well as of glycogen, some glycolytic intermediates, pyruvate, and lactate were assessed in 11 fasted dogs exercised at 20 C on treadmill to exhaustion. Without cooling, dogs were able to run 57 min, and their rectal (Tre) and muscle (Tm) temperatures increased to 41.8 and 43.0 C, respectively. Cooling with ice packs prolonged the ability to run by 45 percent, and resulted in lower Tre (by 1.1 C) and Tm (by 1.2 C). Depletion of muscle content of total high-energy phosphates (ATP + CrP) and glycogen, and increases in contents of AMP, pyruvate, and lactate were lower in cooled dogs than in non-cooled dogs. The muscle content of lactiate correlated positively with TM. These results indicate that hypothermia accelerates glycolysis, and shifts the equilibrium between high- and low-energy phosphates in favor of the latter. The adverse effect of hypothermia on muscle metabolism may be relevant to the limitation of endurance.

  10. Job Accommodations Availability and Utilization Among People With Lupus: An Examination of Workplace Activity Limitations and Work Context Factors.

    Science.gov (United States)

    Al Dhanhani, Ali M; Gignac, Monique A M; Beaton, Dorcas E; Su, Jiandong; Fortin, Paul R

    2015-11-01

    The aim of this study was to examine the availability of diverse job accommodations (or flexible working arrangements) and to describe their use among people with systemic lupus erythematosus (lupus), as well as to examine factors associated with the use of job accommodations. A mail survey was sent to adult lupus patients receiving care from a lupus clinic based in Toronto, Canada. The survey assessed demographic information, self-reported disease activity, work history, workplace activity limitations, job strain, and the availability and use of job accommodations. Standard multivariable linear regression analysis was used to examine factors associated with the use of job accommodations. We received 362 responses of 604 mailed surveys (60% response rate). Participants who were employed within the last 5 years, but who were not currently working, were less likely than currently employed participants to report having had job accommodations available to them at their last place of employment. The use of job accommodations was reported by 70% of currently employed respondents and by 72% of those not currently employed. The most common job accommodation used was sick leave days. Factors positively associated with the use of job accommodations among those who were employed included higher levels of education, being diagnosed with fibromyalgia, at least 1 episode of short-term work disability, not belonging to a union, greater workplace activity limitations, and greater job strain. The use of job accommodations among people with lupus is common. Work context factors, such as workplace activity limitations and job strain, are the main factors associated with the use of job accommodations. © 2015, American College of Rheumatology.

  11. Study of DNA Origami Dimerization and Dimer Dissociation Dynamics and of the Factors that Limit Dimerization.

    Science.gov (United States)

    Liber, Miran; Tomov, Toma E; Tsukanov, Roman; Berger, Yaron; Popov, Mary; Khara, Dinesh C; Nir, Eyal

    2018-06-01

    Organizing DNA origami building blocks into higher order structures is essential for fabrication of large structurally and functionally diverse devices and molecular machines. Unfortunately, the yields of origami building block attachment reactions are typically not sufficient to allow programed assembly of DNA devices made from more than a few origami building blocks. To investigate possible reasons for these low yields, a detailed single-molecule fluorescence study of the dynamics of rectangular origami dimerization and origami dimer dissociation reactions is conducted. Reactions kinetics and yields are investigated at different origami and ion concentrations, for different ion types, for different lengths of bridging strands, and for the "sticky end" and "weaving welding" attachment techniques. Dimerization yields are never higher than 86%, which is typical for such systems. Analysis of the dynamic data shows that the low yield cannot be explained by thermodynamic instability or structural imperfections of the origami constructs. Atomic force microscopy and gel electrophoresis evidence reveal self-dimerization of the origami monomers, likely via blunt-end interactions made possible by the presence of bridging strands. It is suggested that this mechanism is the major factor that inhibits correct dimerization and means to overcome it are discussed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Apolipoprotein A-I Limits the Negative Effect of Tumor Necrosis Factor on Lymphangiogenesis.

    Science.gov (United States)

    Bisoendial, Radjesh; Tabet, Fatiha; Tak, Paul P; Petrides, Francine; Cuesta Torres, Luisa F; Hou, Liming; Cook, Adam; Barter, Philip J; Weninger, Wolfgang; Rye, Kerry-Anne

    2015-11-01

    Lymphatic endothelial dysfunction underlies the pathogenesis of many chronic inflammatory disorders. The proinflammatory cytokine tumor necrosis factor (TNF) is known for its role in disrupting the function of the lymphatic vasculature. This study investigates the ability of apolipoprotein (apo) A-I, the principal apolipoprotein of high-density lipoproteins, to preserve the normal function of lymphatic endothelial cells treated with TNF. TNF decreased the ability of lymphatic endothelial cells to form tube-like structures. Preincubation of lymphatic endothelial cells with apoA-I attenuated the TNF-mediated inhibition of tube formation in a concentration-dependent manner. In addition, apoA-I reversed the TNF-mediated suppression of lymphatic endothelial cell migration and lymphatic outgrowth in thoracic duct rings. ApoA-I also abrogated the negative effect of TNF on lymphatic neovascularization in an ATP-binding cassette transporter A1-dependent manner. At the molecular level, this involved downregulation of TNF receptor-1 and the conservation of prospero-related homeobox gene-1 expression, a master regulator of lymphangiogenesis. ApoA-I also re-established the normal phenotype of the lymphatic network in the diaphragms of human TNF transgenic mice. ApoA-I restores the neovascularization capacity of the lymphatic system during TNF-mediated inflammation. This study provides a proof-of-concept that high-density lipoprotein-based therapeutic strategies may attenuate chronic inflammation via its action on lymphatic vasculature. © 2015 American Heart Association, Inc.

  13. Limitations of the toxic equivalency factor (TEF) approach for risk assessment of halogenated aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Safe, S. [Texas A and M Univ., College Station, TX (United States). Dept. of Veterinary Physiology and Pharmacology

    1995-12-31

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related halogenated aromatic hydrocarbons (HAHs) are present as complex mixtures of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and biphenyls (PCBs) in most environmental matrices. Risk management of these mixtures utilize the toxic equivalency factor (TEF) approach in which the TCDD (dioxin) or toxic equivalents of a mixture is a summation of the congener concentration (Ci) times TEF{sub i} (potency relative to TCDD) where. TEQ{sub mixture} = {Sigma}[Cil] {times} TEF{sub i}. TEQs are determined only for those HAHs which are aryl hydrocarbon (Ah) receptor agonists and this approach assumes that the toxic or biochemical effects of individual compounds in a mixture are additive. Several in vivo and in vitro laboratory and field studies with different HAH mixtures have been utilized to validate the TEF approach. For some responses, the calculated toxicities of PCDD/PCDF and PCB mixtures predict the observed toxic potencies. However, for fetal cleft palate and immunotoxicity in mice, nonadditive (antagonistic) responses are observed using complex PCB mixtures or binary mixtures containing an Ah receptor agonist with 2,2{prime},4,4{prime},5,5{prime}-hexachlorobiphenyl (PCB153). The potential interactive effects of PCBs and other dietary Ah receptor antagonist suggest that the TEF approach for risk management of HAHs requires further refinement and should be used selectively.

  14. FISH CONSUMPTION, METHYLMERCURY, AND HUMAN HEART DISEASE.

    Energy Technology Data Exchange (ETDEWEB)

    LIPFERT, F.W.; SULLIVAN, T.M.

    2005-09-21

    Environmental mercury continues to be of concern to public health advocates, both in the U.S. and abroad, and new research continues to be published. A recent analysis of potential health benefits of reduced mercury emissions has opened a new area of public health concern: adverse effects on the cardiovascular system, which could account for the bulk of the potential economic benefits. The authors were careful to include caveats about the uncertainties of such impacts, but they cited only a fraction of the applicable health effects literature. That literature includes studies of the potentially harmful ingredient (methylmercury, MeHg) in fish, as well as of a beneficial ingredient, omega-3 fatty acids or ''fish oils''. The U.S. Food and Drug Administration (FDA) recently certified that some of these fat compounds that are primarily found in fish ''may be beneficial in reducing coronary heart disease''. This paper briefly summarizes and categorizes the extensive literature on both adverse and beneficial links between fish consumption and cardiovascular health, which are typically based on studies of selected groups of individuals (cohorts). Such studies tend to comprise the ''gold standard'' of epidemiology, but cohorts tend to exhibit a great deal of variability, in part because of the limited numbers of individuals involved and in part because of interactions with other dietary and lifestyle considerations. Note that eating fish will involve exposure to both the beneficial effects of fatty acids and the potentially harmful effects of contaminants like Hg or PCBs, all of which depend on the type of fish but tend to be correlated within a population. As a group, the cohort studies show that eating fish tends to reduce mortality, especially due to heart disease, for consumption rates up to about twice weekly, above which the benefits tend to level off. A Finnish cohort study showed increased mortality risks

  15. Photosynthetic Limitation as a Factor Influencing Yield in Highbush Blueberries (Vaccinium Corymbosum) Grown in a Northern European Environment.

    Science.gov (United States)

    Petridis, Antonios; van der Kaay, Jeroen; Chrysanthou, Elina; McCallum, Susan; Graham, Julie; Hancock, Robert D

    2018-03-24

    Published evidence indicates that nearly 60% of blueberry-producing countries experience yield instability. Yield is a complex trait determined by genetic and environmental factors. Here, using physiological and biochemical approaches, we tested the hypothesis that yield instability results from year-to-year environmental variation that limits carbon assimilation, storage and partitioning. Data indicate that fruit development depends primarily on the daily production of non-structural carbohydrates by leaves and there is no accumulation of a starch buffer to allow continuous ripening under conditions limiting for photosynthesis. Photosynthesis was saturated at moderate light irradiance and this was mainly due to stomatal and biochemical limitations. In a dynamic light environment photosynthesis was furher limited by slow stomatal response to increasing light. Finally, labelling with13CO2 at specific stages of fruit development revealed a relatively even distribution of newly assimilated carbon between stems, roots and fruits, suggesting that the fruit is not a strong sink. We conclude that a significant component of yield variability results from limitations in photosynthetic efficiency that is compounded by an inability to accumulate starch reserves in blueberry storage tissues under a typical northern European environment. This work informs techniques for improving agronomic management and indicates key traits required for yield stability in such environments.

  16. Risk Denial and Socio-Economic Factors Related to High HIV Transmission in a Fishing Community in Rakai, Uganda: A Qualitative Study.

    Directory of Open Access Journals (Sweden)

    Muhamadi Lubega

    Full Text Available In Kasensero fishing community, home of the first recorded case of HIV in Uganda, HIV transmission is still very high with an incidence of 4.3 and 3.1 per 100 person-years in women and men, respectively, and an HIV prevalence of 44%, reaching up to 74% among female sex workers. We explored drivers for the high HIV transmission at Kasensero from the perspective of fishermen and other community members to inform future policy and preventive interventions.20 in-depth interviews including both HIV positive and HIV negative respondents, and 12 focus-group discussions involving a total of 92 respondents from the Kasensero fishing community were conducted during April-September 2014. Content analysis was performed to identify recurrent themes.The socio-economic risk factors for high HIV transmission in Kasensero fishing community cited were multiple and cross-cutting and categorized into the following themes: power of money, risk denial, environmental triggers and a predisposing lifestyle and alcoholism and drug abuse. Others were: peer pressure, poor housing and the search for financial support for both the men and women which made them vulnerable to HIV exposure and or risk behavior.There is a need for context specific combination prevention interventions in Kasensero that includes the fisher folk and other influential community leaders. Such groups could be empowered with the knowledge and social mobilization skills to fight the negative and risky behaviors, perceptions, beliefs, misconceptions and submission attitudes to fate that exposes the community to high HIV transmission. There is also need for government/partners to ensure effective policy implementation, life jackets for all fishermen, improve the poor housing at the community so as to reduce overcrowding and other housing related predispositions to high HIV rates at the community. Work place AIDS-competence teams have been successfully used to address high HIV transmission in similar

  17. Hazard assessment of metals in invasive fish species of the Yamuna River, India in relation to bioaccumulation factor and exposure concentration for human health implications.

    Science.gov (United States)

    Singh, Atul K; Srivastava, Sharad C; Verma, Pankaj; Ansari, Abubakar; Verma, Ambrish

    2014-06-01

    Monitoring of heavy metals was conducted in the Yamuna River considering bioaccumulation factor, exposure concentration, and human health implications which showed contamination levels of copper (Cu), lead (Pb), nickel (Ni), and chromium (Cr) and their dispersion patterns along the river. Largest concentration of Pb in river water was 392 μg L(-1); Cu was 392 μg L(-1) at the extreme downstream, Allahabad and Ni was 146 μg L(-1) at midstream, Agra. Largest concentration of Cu was 617 μg kg(-1), Ni 1,621 μg kg(-1) at midstream while Pb was 1,214 μg kg(-1) at Allahabad in surface sediment. The bioconcentration of Cu, Pb, Ni, and Cr was observed where the largest accumulation of Pb was 2.29 μg kg(-1) in Oreochromis niloticus and 1.55 μg kg(-1) in Cyprinus carpio invaded at Allahabad while largest concentration of Ni was 174 μg kg(-1) in O. niloticus and 124 μg kg(-1) in C. carpio in the midstream of the river. The calculated values of hazard index (HI) for Pb was found more than one which indicated human health concern. Carcinogenic risk value for Ni was again high i.e., 17.02 × 10(-4) which was larger than all other metals studied. The results of this study indicated bioconcentration in fish due to their exposures to heavy metals from different routes which had human health risk implications. Thus, regular environmental monitoring of heavy metal contamination in fish is advocated for assessing food safety since health risk may be associated with the consumption of fish contaminated through exposure to a degraded environment.

  18. Factors limiting microbial growth and activity at a proposed high-level nuclear repository, Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Kieft, T.L.; Kovacik, W.P. Jr.; Ringelberg, D.B.; White, D.C.; Haldeman, D.L.; Amy, P.S.; Hersman, L.E.

    1997-01-01

    As part of the characterization of Yucca Mountain, Nev., as a potential repository for high-level nuclear waste, volcanic tuff was analyzed for microbial abundance and activity. Tuff was collected aseptically from nine sites along a tunnel in Yucca Mountain. Microbial abundance was generally low: direct microscopic cell counts were near detection limits at all sites (3.2 X 10(1) to 2.0 X 10(5) cells g-1 [dry weight]); plate counts of aerobic heterotrophs ranged from 1.0 X 10(1) to 3.2 X 10(3) CFU g-1 (dry weight). Phospholipid fatty acid concentrations (0.1 to 3.7 pmol g-1) also indicated low microbial biomasses: diglyceride fatty acid concentrations, indicative of dead cells, were in a similar range (0.2 to 2.3 pmol g-1). Potential microbial activity was quantified as 14CO2 production in microcosms containing radiolabeled substrates (glucose, acetate, and glutamic acid); amendments with water and nutrient solutions (N and P) were used to test factors potentially limiting this activity. Similarly, the potential for microbial growth and the factors limiting growth were determined by performing plate counts before and after incubating volcanic tuff samples for 24 h under various conditions: ambient moisture, water-amended, and amended with various nutrient solutions (N, P, and organic C). A high potential for microbial activity was demonstrated by high rates of substrate mineralization (as much as 70% of added organic C in 3 weeks). Water was the major limiting factor to growth and microbial activity, while amendments with N and P resulted in little further stimulation. Organic C amendments stimulated growth more than water alone

  19. Life at the limits: peculiar features of lichen symbiosis related to extreme environmental factors

    Science.gov (United States)

    de Vera, J.-P.; Horneck, G.; Rettberg, P.; Ott, S.

    A lichen is a symbiotic association formed by a mycobiont (fungi), a photobiont (algae) and/or a cyanobacteria. The special symbiotic contact and interaction between the bionts in a lichen is a prerequisite for maintainance of viability for each of them during influences by harsh environmental factors. In nature parameters like UV radiation, low or high temperatures and dryness may have a destructive impact on all life functions of an organism. But with lichens the evolution has created a peculiar symbiosis which enables a wide variety of lichen species to colonize habitats where their separate bionts would not be able to survive. The results of our investigations are demonstrating these aspects (de Vera et al. 2003, 2004).We have already investigated the viability of the entire lichen thallus, the embedded spores in lichen apothecia (fruiting bodies) as well as the isolated spores and isolated photobionts after exposure to most extreme conditions caused by simulated space parameters as extreme UV radiation and vacuum. The results presented here focuse on the survival capacity of the isolated photobionts from the two lichen species Xanthoria elegans and Fulgensia bracteata which are not protected by the fungal structure of the lichen thallus. They are based on examinations using a Confocal Laser Scanning Microscopy (CLSM), analysed by modern methods of the Image Tool Program and by culture experiments. In contrast to photobionts embedded in the entire lichen thallus the isolated photobionts are much more sensitve to the extreme conditions of UV radiation and vaccum: while 50 % of the bionts in an entire lichen thallus are able to cope with simulated extreme space conditions (UV-radiation: λ quad ≥ 160nm and vacuum: p = 10-5 Pa) during an exposure time of 2 weeks, the viability of the isolated photobiont cells was already decreasing after 2 hours of exposure. All photobiont cells were inactivated after longer exposure times of about 8 hours. Further more analysis

  20. [Food addiction: Definition, measurement and limits of the concept, associated factors, therapeutic and clinical implications].

    Science.gov (United States)

    Cathelain, Sarah; Brunault, Paul; Ballon, Nicolas; Réveillère, Christian; Courtois, Robert

    2016-12-01

    Addictions, which are characterized by the inability to control a behavior despite existence of physical or psychological consequences, have biological, psychological and social determinants. Although the possibility of developing an addiction to some psychoactive substances (e.g. alcohol, tobacco, cannabis) and to gambling (i.e., gambling disorder) is now well demonstrated, the possibility to develop a non-drug addiction (i.e., behavioral addiction) to certain behaviors which provide pleasure (e.g. eating, having sex, buying things) is still in debate. The concept of food addiction, which refers to people who exhibit substance dependence criteria in relation to some high-fat and high-sugar foods, was recently proposed by applying substance dependence DSM criteria to eating behavior. To assess food addiction, the Yale Food Addiction Scale is now the only self-administered questionnaire (diagnosis and estimate of the number of symptoms of food addiction). Prevalence for food addiction is higher in overweight and obese patients, and in patients with certain psychopathological characteristics (i.e., depression, Attention Deficit Hyperactivity Disorder, high impulsivity), in patients who are single and in patients with neurobiological alterations in the reward system. However, it is still unclear whether food addiction is necessary associated with subsequent increase in body weight and/or obesity. An increasing number of studies demonstrated that drug addiction and food addiction shares some similar clinical, neurobiological and psychopathological and sociocultural risk factors. To test the pertinence to include food addiction as an addiction, it would be interesting to conduct future studies in patients who may experience harms related to their food addiction, including not only patients with obesity, but also patients with metabolic syndrome, type 2 diabetes, hypertension, dyslipidemia, atherosclerosis, stroke, or coronary heart disease. Food addiction is a clinical

  1. Microplastics ingestion by a common tropical freshwater fishing resource.

    Science.gov (United States)

    Silva-Cavalcanti, Jacqueline Santos; Silva, José Diego B; França, Elton José de; Araújo, Maria Christina Barbosa de; Gusmão, Felipe

    2017-02-01

    Microplastics pollution is widespread in marine ecosystems and a major threat to biodiversity. Nevertheless, our knowledge of the impacts of microplastics in freshwater environments and biota is still very limited. The interaction of microplastics with freshwater organisms and the risks associated with the human consumption of organisms that ingested microplastics remain major knowledge gaps. In this study, we assessed the ingestion of microplastics by Hoplosternum littorale, a common freshwater fish heavily consumed by humans in semi-arid regions of South America. We assessed the abundance and diversity of both plastic debris and other food items found in the gut of fishes caught by local fishermen. We observed that 83% of the fish had plastic debris inside the gut, the highest frequency reported for a fish species so far. Most of the plastic debris (88.6%) recovered from the guts of fish were microplastics (microplastics at the urbanized sections of the river, and that the ingestion of microplastics was negatively correlated with the diversity of other food items in the gut of individual fish. Nevertheless, microplastics ingestion appears to have a limited impact on H. littorale, and the consequences of human consumption of this fish were not assessed. Our results suggest freshwater biota are vulnerable to microplastics pollution and that urbanization is a major factor contributing to the pollution of freshwater environments with microplastics. We suggest the gut content of fish could be used as a tool for the qualitative assessment of microplastics pollution in freshwater ecosystems. Further research is needed to determine the processes responsible for the high incidence of microplastics ingestion by H. littorale, and to evaluate the risk posed to humans by the consumption of freshwater fish that ingested microplastics. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Relative merits and limiting factors for x-ray and electron microscopy of thick, hydrated organic materials.

    Science.gov (United States)

    Du, Ming; Jacobsen, Chris

    2018-01-01

    Electron and x-ray microscopes allow one to image the entire, unlabeled structure of hydrated materials at a resolution well beyond what visible light microscopes can achieve. However, both approaches involve ionizing radiation, so that radiation damage must be considered as one of the limits to imaging. Drawing upon earlier work, we describe here a unified approach to estimating the image contrast (and thus the required exposure and corresponding radiation dose) in both x-ray and electron microscopy. This approach accounts for factors such as plural and inelastic scattering, and (in electron microscopy) the use of energy filters to obtain so-called "zero loss" images. As expected, it shows that electron microscopy offers lower dose for specimens thinner than about 1 µm (such as for studies of macromolecules, viruses, bacteria and archaebacteria, and thin sectioned material), while x-ray microscopy offers superior characteristics for imaging thicker specimen such as whole eukaryotic cells, thick-sectioned tissues, and organs. The required radiation dose scales strongly as a function of the desired spatial resolution, allowing one to understand the limits of live and frozen hydrated specimen imaging. Finally, we consider the factors limiting x-ray microscopy of thicker materials, suggesting that specimens as thick as a whole mouse brain can be imaged with x-ray microscopes without significant image degradation should appropriate image reconstruction methods be identified. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Fish pelleting

    African Journals Online (AJOL)

    PUBLICATIONS1

    fish meal pelletizing machine utilized 4kg of ingredients to produce 3.77kg pellets at an effi- ciency of .... Design and fabrication of fish meal pellet processing machine ... 53 ... horsepower for effective torque application on .... two edges were tacked with a spot weld to hold ... then welded on to the shaft making sure that the.

  4. Fish parasites

    DEFF Research Database (Denmark)

    This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems......This book contains 22 chapters on some of the most important parasitic diseases in wild and farmed fish. International experts give updated reviews and provide solutions to the problems...

  5. Fish reproduction

    National Research Council Canada - National Science Library

    Rocha, Maria João; Arukwe, Augustine; Kapoor, B. G

    2008-01-01

    ... of reproductive systems is essential for such studies. Fishes comprise over 28,000 species, with a remarkable variability in morphology, physiology and environmental adaptation. Knowledge on fish reproduction is scattered across numerous sources that shows a dynamic research field. The Editors believe it to be an opportune moment for a...

  6. Evaluation of prognostic factors in liver-limited metastatic colorectal cancer: a preplanned analysis of the FIRE-1 trial

    Science.gov (United States)

    Giessen, C; Fischer von Weikersthal, L; Laubender, R P; Stintzing, S; Modest, D P; Schalhorn, A; Schulz, C; Heinemann, V

    2013-01-01

    Background: Liver-limited disease (LLD) denotes a specific subgroup of metastatic colorectal cancer (mCRC) patients. Patients and Methods: A total of 479 patients with unresectable mCRC from an irinotecan-based randomised phase III trial were evaluated. Patients with LLD and non-LLD and hepatic resection were differentiated. Based on baseline patient characteristic, prognostic factors for hepatic resection were evaluated. Furthermore, prognostic factors for median overall survival (OS) were estimated via Cox regression in LLD patients. Results: Secondary liver resection was performed in 38 out of 479 patients (resection rate: 7.9%). Prognostic factors for hepatic resection were LLD, lactate dehydrogenase (LDH), node-negative primary, alkaline phosphatase (AP) and Karnofsky performance status (PS). Median OS was significantly increased after hepatic resection (48 months), whereas OS in LLD (17 months) and non-LLD (19 months) was comparable in non-resected patients. With the inapplicability of Koehne's risk classification in LLD patients, a new score based on only the independent prognostic factors LDH and white blood cell (WBC) provided markedly improved information on the outcome. Conclusion: Patients undergoing hepatic resection showed favourable long-term survival, whereas non-resected LLD patients and non-LLD patients did not differ with regard to progression-free survival and OS. The LDH levels and WBC count were confirmed as prognostic factors and provide a useful and simple score for OS-related risk stratification also in LLD. PMID:23963138

  7. Fish assemblages

    Science.gov (United States)

    McGarvey, Daniel J.; Falke, Jeffrey A.; Li, Hiram W.; Li, Judith; Hauer, F. Richard; Lamberti, G.A.

    2017-01-01

    Methods to sample fishes in stream ecosystems and to analyze the raw data, focusing primarily on assemblage-level (all fish species combined) analyses, are presented in this chapter. We begin with guidance on sample site selection, permitting for fish collection, and information-gathering steps to be completed prior to conducting fieldwork. Basic sampling methods (visual surveying, electrofishing, and seining) are presented with specific instructions for estimating population sizes via visual, capture-recapture, and depletion surveys, in addition to new guidance on environmental DNA (eDNA) methods. Steps to process fish specimens in the field including the use of anesthesia and preservation of whole specimens or tissue samples (for genetic or stable isotope analysis) are also presented. Data analysis methods include characterization of size-structure within populations, estimation of species richness and diversity, and application of fish functional traits. We conclude with three advanced topics in assemblage-level analysis: multidimensional scaling (MDS), ecological networks, and loop analysis.

  8. Small nonnative fishes as predators of larval razorback suckers

    Science.gov (United States)

    Carpenter, J.; Mueller, G.A.

    2008-01-01

    The razorback sucker (Xyrauchen texanus), an endangered big-river fish of the Colorado River basin, has demonstrated no sustainable recruitment in 4 decades, despite presence of spawning adults and larvae. Lack of adequate recruitment has been attributed to several factors, including predation by nonnative fishes. Substantial funding and effort has been expended on mechanically removing nonnative game fishes, typically targeting large predators. As a result, abundance of larger predators has declined, but the abundance of small nonnative fishes has increased in some areas. We conducted laboratory experiments to determine if small nonnative fishes would consume larval razorback suckers. We tested adults of three small species (threadfin shad, Dorosoma petenense; red shiner, Cyprinella lutrensis; fathead minnow, Pimephales promelas) and juveniles of six larger species (common carp, Cyprinus carpio; yellow bullhead, Ameiurus natalis; channel catfish, Ictalurus punctatus; rainbow trout, Oncorhynchus mykiss; green sunfish, Lepomis cyanellus; bluegill, L. macrochirus). These nonnative fishes span a broad ecological range and are abundant within the historical range of the razorback sucker. All nine species fed on larval razorback suckers (total length, 9-16 mm). Our results suggest that predation by small nonnative fishes could be responsible for limiting recovery of this endangered species.

  9. Oral vaccination of fish

    NARCIS (Netherlands)

    Embregts, Carmen W.E.; Forlenza, Maria

    2016-01-01

    The limited number of oral vaccines currently approved for use in humans and veterinary species clearly illustrates that development of efficacious and safe oral vaccines has been a challenge not only for fish immunologists. The insufficient efficacy of oral vaccines is partly due to antigen

  10. An empirical study to determine factors that motivate and limit the implementation of ICT in healthcare environments.

    Science.gov (United States)

    Gururajan, Raj; Hafeez-Baig, Abdul

    2014-12-23

    The maturity and usage of wireless technology has influenced health services, and this has raised expectations from users that healthcare services will become more affordable due to technology growth. There is increasing evidence to justify this expectation, as telehealth is becoming more and more prevalent in many countries. Thus, health services are now offered beyond the boundaries of traditional hospitals, giving rise to many external factors dictating their quality. This has led us to investigate the factors that motivate and limit the implementation of ICT applications in the healthcare domain. We used a mixed method approach with the qualitative aspects leading the quantitative aspects. The main reason for this approach was to understand and explore the domain through the qualitative aspects as we could be part of the discussion. Then we conducted a quantitative survey to extract more responses in order to justify the claims explored in the qualitative process. We found that there are a number of internal and external factors influencing ICT adoption in the healthcare environment so that services can be provided via ICT tools. These factors were grouped under factors contributing to improved outcomes, efficiency and the management of technology. We conceptualised that these three groups of factors drive ICT implementation to assure health services. The main lesson learned from this research was that Information Systems discipline needs to urgently consider health informatics as a serious growth area. We also found that as IS researchers, we need to 'mix' with the health environment in order to understand the environment and then develop suitable methods to answer posited research questions.

  11. A quantitative analysis on the effects of critical factors limiting the effectiveness of species conservation in future time.

    Science.gov (United States)

    Alagador, Diogo; Cerdeira, Jorge Orestes

    2018-03-01

    climate and of multiple-species planning designs added up, making these species especially at risk. Integrated assessments of the factors most likely to limit species persistence are pivotal to achieve effectiveness.

  12. [Analysis of Prognostic Factors and Clinical Characteristics for Patients with Limited Stage Small Cell Lung Cancer with Pleural Effusion].

    Science.gov (United States)

    Xu, Kunpeng; Wang, Youyou; Qi, Jing; Zhao, Lujun; Wang, Ping

    2018-01-20

    Malignant pleural effusion (PE) was generally defined as pleural effusion containing tumors with poor prognosis. Some kinds of undefined pleural effusions due to too small amount of effusion had poor prognosis too. This study aimed to analyze the clinical characteristics and prognostic factors of patients who suffered from limited-stage small cell lung cancer (LS-SCLC) complicated with pleural effusion. A retrospective analysis included 542 patients who were diagnosed with LS-SCLC and had treatment in our hospital from October 2007 to January 2016. We had observed 109 patients who were diagnosed with pleural effusion at their first visit to the doctor. We analyzed the clinical characters, survival time and the prognostic factors of the 109 patients. Our main observation targets were overall survival (OS) and progression free survival (PFS). The median OS and PFS of whole group were 29.4 and 18.2 months. Before treatment, survival time of patients with PE were significantly shorter than patients without PE (median OS: 21.0 vs 31.7 months; median PFS: 14.1 vs 9.1 months; Log-rank, P=0.001, P=0.014). Multi-factor analysis of multivariate Cox shows PE was the independent prognostic factor of LS-SCLC (P=0.04). Single factor analysis showed factors affecting PE patient's survival time included clinical stages, lymph node (LN) stages, KPS scores, pulmonary atelectasis and the state of pleural after treatment. Cox multi-factor analysis reminded that the state of pleural effusion after treatment was the independent prognostic factor of LS-SCLC complicated with pleural effusion (P=0.016). There were three groups was apportioned patients without pleural effusion before treatment (group 1; n=433), patients whose pleural effusion disappeared after treatment (group 2; n=67) and patients whose pleural effusion didn't disappear after treatment (group 3; n=32).The median OS were 31.7, 23.2, 16.8 months in the group 1, 2, 3 and the median PFS were 19.1, 17.9, 11.4 months. Obvious

  13. PHYSICO-CHEMICAL LIMITATIVE FACTORS FOR GROWTH AND DEVELOPMENT IN STERLET (ACIPENSER RUTHENUS LINNAEUS, 1758 IN EXTENSIVELY SYSTEM

    Directory of Open Access Journals (Sweden)

    R. C. DIMA

    2009-10-01

    Full Text Available The oldest and most common method of increasing fish is a fish breeding ponds in which the supervision of nutrition and growth of biological material. Sterlet (Acipenser ruthenus ruthenus Linnaeus 1785 is the 4th of sturgeon scale and economic importance as a share of production of these fish .Monitoring of physicochemical parameters of sturgeons ponds has a crucial role to obtain satisfactory yields both in qualitative and quantitative. Chemical characteristics of water were determined in laboratory ecosystems Chemistry of the Institute of Research and Development for Ecology Aquaculture, Fisheries and Aquaculture Galaţi for the samples have been taken of the total water. Determination of the chemical characteristics was performed by standardized methods. Physic-chemical parameters of water were determined according to norm on the classification of surface water quality in order to establish the ecological status of water (Order no. 161/2006, for Class II of quality.

  14. One Fish, Two Fish, Redfish, You Fish!

    Science.gov (United States)

    White, Katherine; Timmons, Maryellen; Medders, Paul

    2011-01-01

    The recreational fishing activity presented in this article provides a hands-on, problem-based experience for students; it unites biology, math, economics, environmental policy, and population dynamics concepts. In addition, the activity allows students to shape environmental policy in a realistic setting and evaluate their peers' work. By…

  15. Experimental investigation of factors limiting slow axis beam quality in 9xx nm high power broad area diode lasers

    International Nuclear Information System (INIS)

    Winterfeldt, M.; Crump, P.; Wenzel, H.; Erbert, G.; Tränkle, G.

    2014-01-01

    GaAs-based broad-area diode lasers are needed with improved lateral beam parameter product (BPP lat ) at high power. An experimental study of the factors limiting BPP lat is therefore presented, using extreme double-asymmetric (EDAS) vertical structures emitting at 910 nm. Continuous wave, pulsed and polarization-resolved measurements are presented and compared to thermal simulation. The importance of thermal and packaging-induced effects is determined by comparing junction -up and -down devices. Process factors are clarified by comparing diodes with and without index-guiding trenches. We show that in all cases studied, BPP lat is limited by a non-thermal BPP ground-level and a thermal BPP, which depends linearly on self-heating. Measurements as a function of pulse width confirm that self-heating rather than bias-level dominates. Diodes without trenches show low BPP ground-level, and a thermal BPP which depends strongly on mounting, due to changes in the temperature profile. The additional lateral guiding in diodes with trenches strongly increases the BPP ground-level, but optically isolates the stripe from the device edges, suppressing the influence of the thermal profile, leading to a BPP-slope that is low and independent of mounting. Trenches are also shown to initiate strain fields that cause parasitic TM-polarized emission with large BPP lat , whose influence on total BPP lat remains small, provided the overall polarization purity is >95%

  16. Experimental investigation of factors limiting slow axis beam quality in 9xx nm high power broad area diode lasers

    Science.gov (United States)

    Winterfeldt, M.; Crump, P.; Wenzel, H.; Erbert, G.; Tränkle, G.

    2014-08-01

    GaAs-based broad-area diode lasers are needed with improved lateral beam parameter product (BPPlat) at high power. An experimental study of the factors limiting BPPlat is therefore presented, using extreme double-asymmetric (EDAS) vertical structures emitting at 910 nm. Continuous wave, pulsed and polarization-resolved measurements are presented and compared to thermal simulation. The importance of thermal and packaging-induced effects is determined by comparing junction -up and -down devices. Process factors are clarified by comparing diodes with and without index-guiding trenches. We show that in all cases studied, BPPlat is limited by a non-thermal BPP ground-level and a thermal BPP, which depends linearly on self-heating. Measurements as a function of pulse width confirm that self-heating rather than bias-level dominates. Diodes without trenches show low BPP ground-level, and a thermal BPP which depends strongly on mounting, due to changes in the temperature profile. The additional lateral guiding in diodes with trenches strongly increases the BPP ground-level, but optically isolates the stripe from the device edges, suppressing the influence of the thermal profile, leading to a BPP-slope that is low and independent of mounting. Trenches are also shown to initiate strain fields that cause parasitic TM-polarized emission with large BPPlat, whose influence on total BPPlat remains small, provided the overall polarization purity is >95%.

  17. Why fishing magnifies fluctuations in fish abundance.

    Science.gov (United States)

    Anderson, Christian N K; Hsieh, Chih-hao; Sandin, Stuart A; Hewitt, Roger; Hollowed, Anne; Beddington, John; May, Robert M; Sugihara, George

    2008-04-17

    It is now clear that fished populations can fluctuate more than unharvested stocks. However, it is not clear why. Here we distinguish among three major competing mechanisms for this phenomenon, by using the 50-year California Cooperative Oceanic Fisheries Investigations (CalCOFI) larval fish record. First, variable fishing pressure directly increases variability in exploited populations. Second, commercial fishing can decrease the average body size and age of a stock, causing the truncated population to track environmental fluctuations directly. Third, age-truncated or juvenescent populations have increasingly unstable population dynamics because of changing demographic parameters such as intrinsic growth rates. We find no evidence for the first hypothesis, limited evidence for the second and strong evidence for the third. Therefore, in California Current fisheries, increased temporal variability in the population does not arise from variable exploitation, nor does it reflect direct environmental tracking. More fundamentally, it arises from increased instability in dynamics. This finding has implications for resource management as an empirical example of how selective harvesting can alter the basic dynamics of exploited populations, and lead to unstable booms and busts that can precede systematic declines in stock levels.

  18. Assessment of Heavy Metal in Self-caught Saltwater Fish from Port Dickson Coastal Water (Malaysia)

    International Nuclear Information System (INIS)

    Praveena, S.M.; Lin, C.L.S.

    2015-01-01

    Freshwater fish has been studied and reported numerously. However, little attention has been made and limited studies available on local marine fish in Malaysia. Thus, in this study, concentrations of heavy metals (Cd, Cr, Pb and Cu) were studied in four major local marine fish Megalaspis cordyla (hardtail scad), Rastrelliger kanagurta (Indian mackerel), Selaroides leptolepis (yellow stripe scad) and Sardinella fimbriata (fringescale sardinella). The study was also intended to estimate potential health risk assessment from these heavy metals to the consumption of fish and assess maximum allowable fish consumption rate. The range of heavy metal concentrations were 0.053-0.096 mg/ kg for Cd, 1.16-2.34 mg/ kg for Cr, 8.34-12.44 mg/ kg for Pb and 1.40-3.21 mg/ kg for Cu in four major self-caught saltwater fish. Heavy metal levels of Cd and Cu in the local marine fish from Port Dickson are below the limit enforced by Food Regulations (1985) while the levels of Cr and Pb have exceeded the limit. Potential health risks associated with Cd, Cr, Cu and Pb were assessed based on target hazard quotients. HQ values calculated for Cd, Cr and Cu were less than 1, thus indicate that no adverse effects while HQ values for Pb exceeded 1 for all the fish species assessed with the exception of Megalaspis spp and Sardinella sppa. Cr was the highest while Pb concentrations were the lowest in all the studied fish samples for maximum allowable fish consumption rate. A long term monitoring program is crucial to be done in coastal areas with high consumption of local marine fish along Port Dickson to obtain real consumption rates and other cofounders factors in local population. (author)

  19. Macrobioerosion in Porites corals in subtropical northern South China Sea: a limiting factor for high-latitude reef framework development

    Science.gov (United States)

    Chen, Tianran; Li, Shu; Yu, Kefu

    2013-03-01

    Bioerosion is an important limiting factor in carbonate accretion and reef framework development; however, few studies have quantified the direct impact of macroborers on high-latitude coral communities, which are viewed as potential refuge during a period of global warming. In this study, internal macrobioerosion of Porites corals was examined at Daya Bay, subtropical northern South China Sea. The principal borers were the bivalve Lithophaga spp. and the sponges Cliona spp. and Cliothosa spp. (≥80 %), while sipunculid and polychaete worms and barnacles accounted for small amounts of bioerosion (≤20 %). Porites corals were heavily bioeroded in areas impacted by aquacultural and urban activities (10.34-27.55 %) compared with corals in relatively unpolluted areas (2.18-6.76 %). High levels of bioerosion, especially boring bivalve infestation, significantly weaken the corals and increase their susceptibility to dislodgement and fragmentation in typhoons, limiting accumulation of limestone framework. This study implies that carbonate accretion and reef development for high-latitude coral communities may be limited in future high-CO2 and eutrophication-stressed environments.

  20. Thermal onset of cellular and endocrine stress responses correspond to ecological limits in brook trout, an iconic cold-water fish

    Science.gov (United States)

    Chadwick, Joseph G; Nislow, Kieth H; McCormick, Stephen

    2015-01-01

    Climate change is predicted to change the distribution and abundance of species, yet underlying physiological mechanisms are complex and methods for detecting populations at risk from rising temperature are poorly developed. There is increasing interest in using physiological mediators of the stress response as indicators of individual and population-level response to environmental stressors. Here, we use laboratory experiments to show that the temperature thresholds in brook trout (Salvelinus fontinalis) for increased gill heat shock protein-70 (20.7°C) and plasma glucose (21.2°C) are similar to their proposed thermal ecological limit of 21.0°C. Field assays demonstrated increased plasma glucose, cortisol and heat shock protein-70 concentrations at field sites where mean daily temperature exceeded 21.0°C. Furthermore, population densities of brook trout were lowest at field sites where temperatures were warm enough to induce a stress response, and a co-occurring species with a higher thermal tolerance showed no evidence of physiological stress at a warm site. The congruence of stress responses and proposed thermal limits supports the use of these thresholds in models of changes in trout distribution under climate change scenarios and suggests that the induction of the stress response by elevated temperature may play a key role in driving the distribution of species.

  1. Older Asian Americans and Pacific Islanders with Activities of Daily Living (ADL Limitations: Immigration and Other Factors Associated with Institutionalization

    Directory of Open Access Journals (Sweden)

    Esme Fuller-Thomson

    2012-09-01

    Full Text Available This study determined the national prevalence and profile of Asian Americans with Activities of Daily Living (ADL limitations and identified factors associated with institutionalization. Data were obtained from 2006 American Community Survey, which replaced the long-form of the US Census. The data are nationally representative of both institutionalized and community-dwelling older adults. Respondents were Vietnamese (n = 203, Korean (n = 131, Japanese (n = 193, Filipino (n = 309, Asian Indian (n = 169, Chinese (n = 404, Hawaiian/Pacific Islander (n = 54, and non-Hispanic whites (n = 55,040 aged 55 and over who all had ADL limitations. The prevalence of institutionalized among those with ADL limitations varies substantially from 4.7% of Asian Indians to 18.8% of Korean Americans with ADL limitations. Every AAPI group had a lower prevalence of institutionalization than disabled Non-Hispanic whites older adults (23.8% (p < 0.001. After adjustment for socio-demographic characteristics, Asian Indians, Vietnamese, Japanese, Filipino, and Chinese had significantly lower odds of institutionalization than non-Hispanic whites (OR = 0.29, 0.31, 0.58, 0.51, 0.70, respectively. When the sample was restricted to AAPIs, the odds of institutionalization were higher among those who were older, unmarried, cognitively impaired and those who spoke English at home. This variation suggests that aggregating data across the AAPI groups obscures meaningful differences among these subpopulations and substantial inter-group differences may have important implications in the long-term care setting.

  2. Is high consumption of fatty fish during pregnancy a risk factor for fetal growth retardation? A study of 44,824 Danish pregnant women

    DEFF Research Database (Denmark)

    Halldorsson, Th I; Meltzer, H M; Thorsdottir, I

    2007-01-01

    The authors examined the relation between fish consumption during pregnancy and fetal growth among 44,824 women from the Danish National Birth Cohort (1996-2002). They evaluated the associations between consumption of total fish, fatty fish, and lean fish in midpregnancy and birth weight, birth...... length, and head circumference among singleton full-term infants. Fish consumption was ascertained by food frequency questionnaire. The birth of infants classified below the 10th percentile for gestational age and gender was significantly increased among women who consumed more than 60 g of fish per day......, as compared with women who consumed 5 g or less per day. Adjusted odds ratios were 1.24 (95% confidence interval (CI): 1.03, 1.49) for birth weight and 1.21 (95% CI: 1.01, 1.43) for head circumference. The adjusted odds ratio was borderline significant for birth length (odds ratio = 1.20, 95% CI: 1.00, 1...

  3. UV filters bioaccumulation in fish from Iberian river basins

    Energy Technology Data Exchange (ETDEWEB)

    Gago-Ferrero, Pablo [Dept. of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, E-08034 Barcelona (Spain); Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis, 15771 Athens (Greece); Díaz-Cruz, M. Silvia, E-mail: sdcqam@cid.csic.es [Dept. of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, E-08034 Barcelona (Spain); Barceló, Damià [Dept. of Environmental Chemistry, Institute of Environmental Assessment and Water Research (IDAEA), Spanish Council for Scientific Research (CSIC), Jordi Girona 18-26, E-08034 Barcelona (Spain); Catalan Institute for Water Research (ICRA), Parc Científic i Tecnològic de la Universitat de Girona, C/ Emili Grahit, 101 Edifici H2O, E-17003 Girona (Spain)

    2015-06-15

    The occurrence of eight organic UV filters (UV-Fs) was assessed in fish from four Iberian river basins. This group of compounds is extensively used in cosmetic products and other industrial goods to avoid the damaging effects of UV radiation, and has been found to be ubiquitous contaminants in the aquatic ecosystem. In particular, fish are considered by the scientific community to be the most feasible organism for contamination monitoring in aquatic ecosystems. Despite that, studies on the bioaccumulation of UV-F are scarce. In this study fish samples from four Iberian river basins under high anthropogenic pressure were analysed by liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). Benzophenone-3 (BP3), ethylhexyl methoxycinnamate (EHMC), 4-methylbenzylidene camphor (4MBC) and octocrylene (OC) were the predominant pollutants in the fish samples, with concentrations in the range of ng/g dry weight (d.w.). The results indicated that most polluted area corresponded to Guadalquivir River basin, where maximum concentrations were found for EHMC (241.7 ng/g d.w.). Sediments from this river basin were also analysed. Lower values were observed in relation to fish for OC and EHMC, ranging from below the limits of detection to 23 ng/g d.w. Accumulation levels of UV-F in the fish were used to calculate biota-sediment accumulation factors (BSAFs). These values were always below 1, in the range of 0.04–0.3, indicating that the target UV-Fs are excreted by fish only to some extent. The fact that the highest concentrations were determined in predators suggests that biomagnification of UV-F may take place along the freshwater food web. - Highlights: • First evidence of UV filters in fish from Iberian rivers • Biota-sediment accumulation factors (BSAFs) were always below 1. • Predator species presented higher UV-F concentrations suggesting trophic magnification.

  4. UV filters bioaccumulation in fish from Iberian river basins

    International Nuclear Information System (INIS)

    Gago-Ferrero, Pablo; Díaz-Cruz, M. Silvia; Barceló, Damià

    2015-01-01

    The occurrence of eight organic UV filters (UV-Fs) was assessed in fish from four Iberian river basins. This group of compounds is extensively used in cosmetic products and other industrial goods to avoid the damaging effects of UV radiation, and has been found to be ubiquitous contaminants in the aquatic ecosystem. In particular, fish are considered by the scientific community to be the most feasible organism for contamination monitoring in aquatic ecosystems. Despite that, studies on the bioaccumulation of UV-F are scarce. In this study fish samples from four Iberian river basins under high anthropogenic pressure were analysed by liquid chromatography–tandem mass spectrometry (HPLC–MS/MS). Benzophenone-3 (BP3), ethylhexyl methoxycinnamate (EHMC), 4-methylbenzylidene camphor (4MBC) and octocrylene (OC) were the predominant pollutants in the fish samples, with concentrations in the range of ng/g dry weight (d.w.). The results indicated that most polluted area corresponded to Guadalquivir River basin, where maximum concentrations were found for EHMC (241.7 ng/g d.w.). Sediments from this river basin were also analysed. Lower values were observed in relation to fish for OC and EHMC, ranging from below the limits of detection to 23 ng/g d.w. Accumulation levels of UV-F in the fish were used to calculate biota-sediment accumulation factors (BSAFs). These values were always below 1, in the range of 0.04–0.3, indicating that the target UV-Fs are excreted by fish only to some extent. The fact that the highest concentrations were determined in predators suggests that biomagnification of UV-F may take place along the freshwater food web. - Highlights: • First evidence of UV filters in fish from Iberian rivers • Biota-sediment accumulation factors (BSAFs) were always below 1. • Predator species presented higher UV-F concentrations suggesting trophic magnification

  5. Alabama ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, and freshwater fish species in Alabama. Vector polygons in this data set represent...

  6. Maryland ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Maryland. Vector polygons in this data...

  7. Hawaii ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for reef, marine, estuarine, and native stream fish species in coastal Hawaii. Vector polygons in this data...

  8. Virginia ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and brackishwater fish species in Virginia. Vector polygons in this data...

  9. Louisiana ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for freshwater (inland) fish species in coastal Louisiana. Vector polygons represent water-bodies and other...

  10. Quantitative methods for analysing cumulative effects on fish migration success: a review.

    Science.gov (United States)

    Johnson, J E; Patterson, D A; Martins, E G; Cooke, S J; Hinch, S G

    2012-07-01

    It is often recognized, but seldom addressed, that a quantitative assessment of the cumulative effects, both additive and non-additive, of multiple stressors on fish survival would provide a more realistic representation of the factors that influence fish migration. This review presents a compilation of analytical methods applied to a well-studied fish migration, a more general review of quantitative multivariable methods, and a synthesis on how to apply new analytical techniques in fish migration studies. A compilation of adult migration papers from Fraser River sockeye salmon Oncorhynchus nerka revealed a limited number of multivariable methods being applied and the sub-optimal reliance on univariable methods for multivariable problems. The literature review of fisheries science, general biology and medicine identified a large number of alternative methods for dealing with cumulative effects, with a limited number of techniques being used in fish migration studies. An evaluation of the different methods revealed that certain classes of multivariable analyses will probably prove useful in future assessments of cumulative effects on fish migration. This overview and evaluation of quantitative methods gathered from the disparate fields should serve as a primer for anyone seeking to quantify cumulative effects on fish migration survival. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  11. The quest for μ → eγ and its experimental limiting factors at future high intensity muon beams

    Energy Technology Data Exchange (ETDEWEB)

    Cavoto, G. [' ' Sapienza' ' Univ., Roma (Italy). Dipt. di Fisica; Istituto Nazionale di Fisica Nucleare, Rome (Italy); Papa, A. [Paul Scherrer Institut, Villigen (Switzerland); Renga, F.; Voena, C. [Istituto Nazionale di Fisica Nucleare, Rome (Italy); Ripiccini, E. [Geneve Univ. (Switzerland). Dept. de Physique Nucleaire et Corpusculaire

    2018-01-15

    The search for the lepton flavor violating decay μ{sup +} → e{sup +}γ will reach an unprecedented level of sensitivity within the next five years thanks to the MEG-II experiment. This experiment will take data at the Paul Scherrer Institut where continuous muon beams are delivered at a rate of about 10{sup 8} muons per second. On the same time scale, accelerator upgrades are expected in various facilities, making it feasible to have continuous beams with an intensity of 10{sup 9} or even 10{sup 10} muons per second. We investigate the experimental limiting factors that will define the ultimate performances, and hence the sensitivity, in the search for μ{sup +} → e{sup +}γ with a continuous beam at these extremely high rates. We then consider some conceptual detector designs and evaluate the corresponding sensitivity as a function of the beam intensity. (orig.)

  12. The hormone prolactin is a novel, endogenous trophic factor able to regulate reactive glia and to limit retinal degeneration.

    Science.gov (United States)

    Arnold, Edith; Thebault, Stéphanie; Baeza-Cruz, German; Arredondo Zamarripa, David; Adán, Norma; Quintanar-Stéphano, Andrés; Condés-Lara, Miguel; Rojas-Piloni, Gerardo; Binart, Nadine; Martínez de la Escalera, Gonzalo; Clapp, Carmen

    2014-01-29

    Retinal degeneration is characterized by the progressive destruction of retinal cells, causing the deterioration and eventual loss of vision. We explored whether the hormone prolactin provides trophic support to retinal cells, thus protecting the retina from degenerative pressure. Inducing hyperprolactinemia limited photoreceptor apoptosis, gliosis, and changes in neurotrophin expression, and it preserved the photoresponse in the phototoxicity model of retinal degeneration, in which continuous exposure of rats to bright light leads to retinal cell death and retinal dysfunction. In this model, the expression levels of prolactin receptors in the retina were upregulated. Moreover, retinas from prolactin receptor-deficient mice exhibited photoresponsive dysfunction and gliosis that correlated with decreased levels of retinal bFGF, GDNF, and BDNF. Collectively, these data unveiled prolactin as a retinal trophic factor that may regulate glial-neuronal cell interactions and is a potential therapeutic molecule against retinal degeneration.

  13. Observation of the fundamental Nyquist noise limit in an ultra-high Q-factor cryogenic bulk acoustic wave cavity

    Energy Technology Data Exchange (ETDEWEB)

    Goryachev, Maxim, E-mail: maxim.goryachev@uwa.edu.au; Ivanov, Eugene N.; Tobar, Michael E. [ARC Centre of Excellence for Engineered Quantum Systems, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia); Kann, Frank van [School of Physics, University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia); Galliou, Serge [Department of Time and Frequency, FEMTO-ST Institute, ENSMM, 26 Chemin de l' Épitaphe, 25000 Besançon (France)

    2014-10-13

    Thermal Nyquist noise fluctuations of high-Q bulk acoustic wave cavities have been observed at cryogenic temperatures with a DC superconducting quantum interference device amplifier. High Q modes with bandwidths of few tens of milliHz produce thermal fluctuations with a signal-to-noise ratio of up to 23 dB. The estimated effective temperature from the Nyquist noise is in good agreement with the physical temperature of the device, confirming the validity of the equivalent circuit model and the non-existence of any excess resonator self-noise. The measurements also confirm that the quality factor remains extremely high (Q > 10{sup 8} at low order overtones) for very weak (thermal) system motion at low temperatures, when compared to values measured with relatively strong external excitation. This result represents an enabling step towards operating such a high-Q acoustic device at the standard quantum limit.

  14. Analysis of factors which limited the spatial variation of barley yield on the forest-steppe chernozems of Kursk region

    Science.gov (United States)

    Belik, Anton; Vasenev, Ivan; Jablonskikh, Lidia; Bozhko, Svetlana

    2017-04-01

    The crop yield is the most important indicator of the efficiency of agricultural production. It is the function that depends on a large number of groups of independent variables, such as the weather, soil fertility and overall culture agriculture. A huge number of combinations of these factors contribute to the formation of high spatial variety of crop yields within small areas, includes the slope agrolandscapes in Kursk region. Spatial variety of yield leads to a significant reduction in the efficiency of agriculture. In this connection, evaluation and analysis of the factors, which limits the yield of field crops is a very urgent proble in agroecology. The research was conducted in the period of 2003-2004 on a representative field. The typical and leached chernozems with the varying thickness and of erosion degree are dominated in soil cover. At the time of field research studied areas were busy by barley. The reseached soils have an average and increased fertility level. Chernozem typical full-face, and the leached contain an average of 4.5-6% humus, close to neutral pH, favorable values of physico-chemical parameters, medium and high content of nutrients. The eroded chernozems differs agrogenic marked declining in fertility parameters. The diversity of meso- and micro-relief in the fields and soil cover influence to significant spatial variety of fertility. For example the content of nutrients in the soil variation can be up to 5-fold level. High spatial heterogeneity of soils fertility ifluence to barley yield variety. During research on the productivity of the field varied in the range of 20-43 c/ha, and 7-44 c/ha (2004). Analysis of the factors, which limited the yield of barley, showed that the first priorities occupy unregulated characterises: slope angle and the classification of soils (subtype and race of chernozem and the difference in the degree of erosion), which determines the development of erosion processes and redistribution available to plants

  15. Experimental investigation of factors limiting slow axis beam quality in 9xx nm high power broad area diode lasers

    Energy Technology Data Exchange (ETDEWEB)

    Winterfeldt, M., E-mail: martin.winterfeldt@fbh-berlin.de; Crump, P.; Wenzel, H.; Erbert, G.; Tränkle, G. [Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)

    2014-08-14

    GaAs-based broad-area diode lasers are needed with improved lateral beam parameter product (BPP{sub lat}) at high power. An experimental study of the factors limiting BPP{sub lat} is therefore presented, using extreme double-asymmetric (EDAS) vertical structures emitting at 910 nm. Continuous wave, pulsed and polarization-resolved measurements are presented and compared to thermal simulation. The importance of thermal and packaging-induced effects is determined by comparing junction -up and -down devices. Process factors are clarified by comparing diodes with and without index-guiding trenches. We show that in all cases studied, BPP{sub lat} is limited by a non-thermal BPP ground-level and a thermal BPP, which depends linearly on self-heating. Measurements as a function of pulse width confirm that self-heating rather than bias-level dominates. Diodes without trenches show low BPP ground-level, and a thermal BPP which depends strongly on mounting, due to changes in the temperature profile. The additional lateral guiding in diodes with trenches strongly increases the BPP ground-level, but optically isolates the stripe from the device edges, suppressing the influence of the thermal profile, leading to a BPP-slope that is low and independent of mounting. Trenches are also shown to initiate strain fields that cause parasitic TM-polarized emission with large BPP{sub lat}, whose influence on total BPP{sub lat} remains small, provided the overall polarization purity is >95%.

  16. Deposition and cycling of sulfur controls mercury accumulation in Isle Royale fish

    Energy Technology Data Exchange (ETDEWEB)

    Paul E. Drevnick; Donald E. Canfield; Patrick R. Gorski (and others) [Miami University, Oxford, OH (United States). Department of Zoology

    2007-11-01

    Mercury contamination of fish is a global problem. Consumption of contaminated fish is the primary route of methylmercury exposure in humans and is detrimental to health. Newly mandated reductions in anthropogenic mercury emissions aim to reduce atmospheric mercury deposition and thus mercury concentrations in fish. However, factors other than mercury deposition are important for mercury bioaccumulation in fish. In the lakes of Isle Royale, U.S.A., reduced rates of sulfate deposition since the Clean Air Act of 1970 have caused mercury concentrations in fish to decline to levels that are safe for human consumption, even without a discernible decrease in mercury deposition. Therefore, reductions in anthropogenic sulfur emissions may provide a synergistic solution to the mercury problem in sulfate-limited freshwaters. 71 refs., 3 figs., 1 tab.

  17. Sleep Disordered Breathing in Four Resource-Limited Settings in Peru: Prevalence, Risk Factors, and Association with Chronic Diseases.

    Science.gov (United States)

    Schwartz, Noah G; Rattner, Adi; Schwartz, Alan R; Mokhlesi, Babak; Gilman, Robert H; Bernabe-Ortiz, Antonio; Miranda, J Jaime; Checkley, William

    2015-09-01

    Sleep disordered breathing (SDB) is a highly prevalent condition in high-income countries, with major consequences for cardiopulmonary health, public safety, healthcare utilization, and mortality. However, its prevalence and effect in low- and middle-income countries are less well known. We sought to determine the prevalence, risk factors, and comorbidities of SDB symptoms in four resource-limited settings. Cross-sectional analysis of the CRONICAS Cohort, a population-based age- and sex-stratified sample. Four resource-limited settings in Peru varying in altitude, urbanization, and air pollution. There were 2,682 adults aged 35 to 92 y. Self-reported SDB symptoms (habitual snoring, observed apneas, Epworth Sleepiness Scale), sociodemographics, medical history, anthropometrics, spirometry, blood biomarkers were reported. We found a high prevalence of habitual snoring (30.2%, 95% confidence interval [CI] 28.5-32.0%), observed apneas (20.9%, 95% CI 19.4-22.5%) and excessive daytime sleepiness (18.6%, 95% CI 17.1-20.1%). SDB symptoms varied across sites; prevalence and adjusted odds for habitual snoring were greatest at sea level, whereas those for observed apneas were greatest at high altitude. In multivariable analysis, habitual snoring was associated with older age, male sex, body mass index (BMI), and higher socioeconomic status; observed apneas were associated with BMI; and excessive daytime sleepiness was associated with older age, female sex, and medium socioeconomic status. Adjusted odds of cardiovascular disease, depression, and hypertension and total chronic disease burden increased progressively with the number of SDB symptoms. A threefold increase in the odds of having an additional chronic comorbid disease (adjusted odds ratio 3.57, 95% CI 2.18-5.84) was observed in those with all three versus no SDB symptoms. Sleep disordered breathing symptoms were highly prevalent, varied widely across four resource-limited settings in Peru, and exhibited strong

  18. Fish sampling with active methods

    Czech Academy of Sciences Publication Activity Database

    Kubečka, Jan; Godo, O. R.; Hickley, P.; Prchalová, Marie; Říha, Milan; Rudstam, L.; Welcomme, R.

    2012-01-01

    Roč. 123, July (2012), s. 1-3 ISSN 0165-7836 Institutional support: RVO:60077344 Keywords : fish stock assessment * active and passive gear * intercalibration Subject RIV: EH - Ecology, Behaviour Impact factor: 1.695, year: 2012

  19. DRIVING AND LIMITING FACTORS IN THE FARM MANAGEMENT BY YOUNG FARMERS IN THE CONTEXT OF SURVEY RESEARCH

    Directory of Open Access Journals (Sweden)

    Barbara Kiełbasa

    2016-03-01

    Full Text Available The purpose of the study was to identify driving and limiting factors of farm management in a region of fragmented agriculture. The paper presents the results of the research conducted in the South-Eastern Poland (Macroregion of Małopolska and Pogórze. The survey was conducted in 2014 in the farms managed by young farmers, i.e. the benefi ciaries of the measure “Setting up of young farmers” from the RDP 2007–2013, with the use of a survey method with a questionnaire interview. The research was empirical, and its main goal was to present a case study of the farm management by young farmers in terms of specifi c management barriers. The results of the studies pointed to the fragmented agrarian structure as the one of the biggest barriers of the eff ective farm management. The young farmers pointed that fragmented agrarian structure signifi cantly impedes the purchase or lease of agricultural land, and the farm development in the same way. The survey pointed to the factors that contribute to the young farmers: the entrepreneurial attitude, activity and creativity, training, the management knowledge and better access to the Common Agricultural Policy instruments.

  20. Fishing Access Areas

    Data.gov (United States)

    Vermont Center for Geographic Information — The Vermont Fish & Wildlife Department maintains developed fishing access areas. These sites provide public access to waters in Vermont for shore fishing...

  1. Long-term tolerability of PRRT in 807 patients with neuroendocrine tumours: the value and limitations of clinical factors

    International Nuclear Information System (INIS)

    Bodei, Lisa; Grana, Chiara M.; Kidd, Mark; Drozdov, Ignat; Lepensky, Christopher; Modlin, Irvin M.; Paganelli, Giovanni; Cremonesi, Marta; Kwekkeboom, Dik J.; Krenning, Eric P.; Baum, Richard P.

    2015-01-01

    occurred in 1.1 % of patients (modelled by the clinical data in 18 %, p < 0.0001). Identified risk factors provide a limited (<30 %) risk estimate even with target tissue dosimetry. These data strongly suggest the existence of unidentified individual susceptibilities to radiation-associated disease. (orig.)

  2. Long-term tolerability of PRRT in 807 patients with neuroendocrine tumours: the value and limitations of clinical factors

    Energy Technology Data Exchange (ETDEWEB)

    Bodei, Lisa; Grana, Chiara M. [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); Kidd, Mark; Drozdov, Ignat; Lepensky, Christopher; Modlin, Irvin M. [Yale School of Medicine, Department of Surgery, New Haven, CT (United States); Paganelli, Giovanni [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine and Radiometabolic Units, Meldola (Italy); Cremonesi, Marta [European Institute of Oncology, Division of Medical Physics, Milan (Italy); Kwekkeboom, Dik J.; Krenning, Eric P. [Erasmus Medical Center, Department of Nuclear Medicine, Rotterdam (Netherlands); Baum, Richard P. [Zentralklinik Bad Berka, Theranostics Center for Molecular Radiotheraphy and Molecular Imaging, Bad Berka (Germany)

    2015-01-15

    9 months, p = 0.01) were relevant. Acute leukaemia occurred in 1.1 % of patients (modelled by the clinical data in 18 %, p < 0.0001). Identified risk factors provide a limited (<30 %) risk estimate even with target tissue dosimetry. These data strongly suggest the existence of unidentified individual susceptibilities to radiation-associated disease. (orig.)

  3. Contribution of modifiable risk factors for hypertension and type-2 diabetes in Peruvian resource-limited settings.

    Science.gov (United States)

    Bernabé-Ortiz, Antonio; Carrillo-Larco, Rodrigo M; Gilman, Robert H; Checkley, William; Smeeth, Liam; Miranda, J Jaime

    2016-01-01

    It is important to understand the local burden of non-communicable diseases including within-country heterogeneity. The aim of this study was to characterise hypertension and type-2 diabetes profiles across different Peruvian geographical settings emphasising the assessment of modifiable risk factors. Analysis of the CRONICAS Cohort Study baseline assessment was conducted. Cardiometabolic outcomes were blood pressure categories (hypertension, prehypertension, normal) and glucose metabolism disorder status (diabetes, prediabetes, normal). Exposures were study setting and six modifiable factors (smoking, alcohol drinking, leisure time and transport-related physical activity levels, TV watching, fruit/vegetables intake and obesity). Poisson regression models were used to report prevalence ratios (PR). Population attributable risks (PAR) were also estimated. Data from 3238 participants, 48.3% male, mean age 45.3 years, were analysed. Age-standardised (WHO population) prevalence of prehypertension and hypertension was 24% and 16%, whereas for prediabetes and type-2 diabetes it was 18% and 6%, respectively. Outcomes varied according to study setting (pdiabetes. PAR showed that obesity was an important determinant for hypertension (15.7%) and type-2 diabetes (23.9%). There is an evident heterogeneity in the prevalence of and risk factors for hypertension and diabetes within Peru. Prehypertension and prediabetes are highly prevalent across settings. Our results emphasise the need of understanding the epidemiology of cardiometabolic conditions to appropriately implement interventions to tackle the burden of non-communicable diseases. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  4. Placental growth factor neutralising antibodies give limited anti-angiogenic effects in an in vitro organotypic angiogenesis model.

    Science.gov (United States)

    Brave, Sandra R; Eberlein, Cath; Shibuya, Masabumi; Wedge, Stephen R; Barry, Simon T

    2010-12-01

    Vascular Endothelial Growth Factor Receptor (VEGFR) mediated signalling drives angiogenesis. This is predominantly attributed to the activity of VEGFR-2 following binding of VEGF-A. Whether other members of the VEGFR and ligand families such as VEGFR-1 and its ligand Placental Growth Factor (PlGF) can also contribute to developmental and pathological angiogenesis is less clear. We explored the function of PlGF in VEGF-A dependent angiogenesis using an in vitro co-culture assay in which endothelial cells are cultured on a fibroblast feeder layer. In the presence of 2% FS MCDB media (containing limited growth factors) in vitro endothelial tube formation is driven by endogenous angiogenic stimuli which are produced by the fibroblast and endothelial cells. Under these conditions independent sequestration of either free VEGF-A or PlGF with polyclonal and monoclonal antibodies inhibited tube formation suggesting that both ligands are required to drive an angiogenic response. Endothelial tube formation could only be driven within this assay by the addition of exogenous VEGF-A, VEGF-E or VEGF-A/PlGF heterodimer, but not by PlGF alone, implying that activation of either VEGFR-2/VEGFR-1 heterodimers or VEGFR-2 homodimers were responsible for eliciting an angiogenic response directly, but not VEGFR-1 homodimers. In contrast to results obtained with an endogenous angiogenic drive, sequestration of PlGF did not affect endothelial tube formation when the assay was driven by 1 ng/ml exogenous VEGF-A. These data suggest that although neutralising PlGF can be shown to reduce endothelial tube formation in vitro, this effect is only observed under restricted culture conditions and is influenced by VEGF-A. Such data questions whether neutralising PlGF would have a therapeutic benefit in vivo in the presence of pathological concentrations of VEGF-A.

  5. Matching metal pollution with bioavailability, bioaccumulation and biomarkers response in fish (Centropomus parallelus) resident in neotropical estuaries.

    Science.gov (United States)

    Souza, Iara C; Duarte, Ian D; Pimentel, Natieli Q; Rocha, Lívia D; Morozesk, Mariana; Bonomo, Marina M; Azevedo, Vinicius C; Pereira, Camilo D S; Monferrán, Magdalena V; Milanez, Camilla R D; Matsumoto, Silvia T; Wunderlin, Daniel A; Fernandes, Marisa N

    2013-09-01

    Two neotropical estuaries affected by different anthropogenic factors were studied. We report levels of metals and metalloids in water and sediment as well as their influence on genetic, biochemical and morphological biomarkers in the native fish Centropomus parallelus. Biomarkers reflected the fish health status. Multivariate statistics indicated both spatial and temporal changes in both water and sediment, which are linked to the elemental composition and health status of inhabitant fish, showing the biggest influence of surface water, followed by sediments and interstitial water. Bioaccumulation in fish muscle was useful to identify elements that were below detection limits in water, pointing out the risk of consuming fish exceeding allowance limits for some elements (As and Hg in this case). Multivariate statistics, including physical, chemical and biological issues, presents a suitable tool, integrating data from different origin allocated in the same estuary, which could be useful for future studies on estuarine systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

  6. Immunity to fish rhabdoviruses

    Science.gov (United States)

    Purcell, Maureen K.; Laing, Kerry J.; Winton, James R.

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN) system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M) protein to mediate host-cell shutoff and the non-virion (NV) protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  7. Immunity to fish rhabdoviruses.

    Science.gov (United States)

    Purcell, Maureen K; Laing, Kerry J; Winton, James R

    2012-01-01

    Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN) system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M) protein to mediate host-cell shutoff and the non‑virion (NV) protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  8. Immunity to Fish Rhabdoviruses

    Directory of Open Access Journals (Sweden)

    Maureen K. Purcell

    2012-01-01

    Full Text Available Members of the family Rhabdoviridae are single-stranded RNA viruses and globally important pathogens of wild and cultured fish and thus relatively well studied in their respective hosts or other model systems. Here, we review the protective immune mechanisms that fish mount in response to rhabdovirus infections. Teleost fish possess the principal components of innate and adaptive immunity found in other vertebrates. Neutralizing antibodies are critical for long-term protection from fish rhabdoviruses, but several studies also indicate a role for cell-mediated immunity. Survival of acute rhabdoviral infection is also dependent on innate immunity, particularly the interferon (IFN system that is rapidly induced in response to infection. Paradoxically, rhabdoviruses are sensitive to the effects of IFN but virulent rhabdoviruses can continue to replicate owing to the abilities of the matrix (M protein to mediate host-cell shutoff and the non‑virion (NV protein to subvert programmed cell death and suppress functional IFN. While many basic features of the fish immune response to rhabdovirus infections are becoming better understood, much less is known about how factors in the environment affect the ecology of rhabdovirus infections in natural populations of aquatic animals.

  9. Richness patterns in the parasite communities of exotic poeciliid fishes.

    Science.gov (United States)

    Dove, A D

    2000-06-01

    Three species of poeciliids (Gambusia holbrooki, Xiphophorus helleri and X. maculatus) and 15 species of ecologically similar native freshwater fishes (mainly eleotrids, ambassids, melanotaeniids and retropinnids) were examined for parasite richness to investigate parasite flux, qualitative differences, quantitative differences and the structuring factors in parasite communities in the 2 fish types in Queensland, Australia. Theory suggests that poeciliids would harbour depauperate parasite communities. Results supported this hypothesis; poeciliids harboured more species-poor parasite infracommunities and regional faunas than natives (P analysis of presence/absence data for poeciliids and the 6 most-sampled native fishes revealed that parasite communities of the 2 fish groups are qualitatively distinct; the proportion of parasite species with complex life-cycles was lower in poeciliids than in native species, and Myxosporea, Microspora, Coccidia and parasitic Crustacea were all absent from poeciliids. Limited exchange of parasite species has occurred between natives and poeciliids. Logistic ordinal regression analysis revealed that fish origin (exotic or native), environmental disturbance and host sex were all significant determinants of parasite community richness (P competitive advantage over native fishes because of their lack of parasites.

  10. Effects of offshore wind power on the pelagic fish; Effekter av havsbaserad vindkraft paa pelagisk fisk

    Energy Technology Data Exchange (ETDEWEB)

    Axenrot, Thomas (SLU, Institutionen foer Akvatiska Resurser, Soetvattenlaboratoriet (Sweden)); Didrikas, Tomas (AquaBiota Water Research AB (Sweden); Stockholms universitet (Sweden))

    2012-02-15

    Marine wind parks are being planned for and built in coastal and shallow offshore areas in response to an increasing demand for renewable energy. Today's knowledge is limited about possible effects on fish from habitat change and generated underwater sound when wind parks are running. There may also be consequences for the fishery. Studies on fish hearing have shown that many fishes hear low frequency sound like that produced by wind turbines. This study consists of two parts. The first part of the study investigated pelagic fish abundance and spatial distribution at one wind park and two reference areas (200 m to 10 km distance from fundaments) at five different occasions from 2005 through 2007 in the Kalmar Sound of the Baltic Sea. The highest fish densities was found in the most remote reference area. The difference between areas was statistically significant for fish of the size groups 30-80 mm (stickleback), 80-140 mm (sprat, small herring) and 140-250 mm (adult herring). For fish >250 mm, representing cod and salmon, no statistically significant difference between areas was observed. For one group (sticklebacks) Area was significantly pointed out as the most important factor for the observed differences in fish density. No data on fish densities in the investigated areas were collected before the wind park (Utgrunden 1) was built which is a drawback to this part of the study. The second part of the study focused on possible effects of underwater sound generated by wind turbines on fish behaviour in the close vicinity of the fundaments (2-35 m distance). Stationary horizontal acoustics was used to estimate fish abundance and swimming speed in relation to turbine rotor speed and electricity production. The changes of abundance were not consistent and difficult to interpret. Fish swimming speed decreased with increasing turbine rotor speed and electricity production. However, it cannot be distinguished if this was an effect of sound emitted by wind turbines

  11. MERCURY (Hg CONTENT OF MEAT TILAPIA FISH (Oreochromis niloticus WERE CULTIVATED IN PALANGKA RAYA CITY

    Directory of Open Access Journals (Sweden)

    Ciptadi

    2015-11-01

    Full Text Available Tilapia fish as Palangkarayan food are mostly cultivated in the river which exposed by mercury. To get information whether the fish have been contaminated by mercury, the mercury determination of tilapia fish meat cultivated in Kahayan river was carried out. The fish were analyzed based on age and the cultivation environment that are fishes cages in Kahayan river and isolated pond from streams of Kahayan river are also studied. The concentration of mercury in the flesh of tilapia with 5-7 months, kept in cages used to identify the content of mercury in fish tilapia cages in Kahayan river. The concentration of mercury in the flesh of tilapia reared in ponds aims to compare the mercury content in the tilapia in ponds the same age were used as comparison. The level of mercury in the samples was measured using a Mercury Analyzer. Data concentration of mercury in the flesh of tilapia were analyzed using analysis of variance (ANOVA: single factor with a significance level (α of 5%. The results showed that tilapia fish meat from the cages in the Kahayan river with age of 5-7 months contain mercury as much as 0.0145 ± 0.0005 ppm to 0.017 ± 0.001 ppm, which were lower than the maximum limit of mercury contamination in fish and processed products regulated by ISO 7387 in 2009 of 0.5 ppm. The the analysis of variance showed that the mercury content in tilapia fish meat was different by age and place of cultivation. The content of mercury in the tilapia fish meat increase with the increase of their age. The mercury content in tilapia fish cultivated in the isolated pond lower than that of in the tilapia fish meat cultivated in cages of 0.0115 ± 0.0005 ppm

  12. Do bacteria, not fish, produce 'fish kairomone'?

    NARCIS (Netherlands)

    Ringelberg, J.; Van Gool, E.

    1998-01-01

    Fish-associated chemicals enhance phototactic downward swimming in Daphnia. If perch were treated with the antibiotic ampicillin, this enhancement was significantly decreased. Therefore, not fish, but bacteria associated with fish, seem to produce this kairomone. [KEYWORDS: Diel vertical migration;

  13. Tendency in fishing development and fish consumption in Serbia

    Directory of Open Access Journals (Sweden)

    Tešić Milan

    2013-01-01

    Full Text Available Production and catch of fish in Serbia increases from year to year, while in the world it reached its peak at the beginning of this century. Serbia has all the favorable natural and economic conditions for further development of fishing. Out of total production, that is, annual fish catch in Serbia, the greatest part is sold by organized purchase, lower part is exported, and the reminder goes to the market through retail. It is well known that food consumption, therefore fish consumption, depends on several factors such as the production level, retail price, consumers purchasing power and their eating habits. Therefore, when analyzing the tendency of production and consumption of fish in Serbia, it is important to investigate the influence of production, price and purchasing power of consumers on it. In order to investigate the set objective, there were used corresponding quantitative data obtained by Statistical Office of the Republic of Serbia. On the basis of the original data, there were determined certain parameters, which were used as variables for calculation of correlational-regressive and maginal analysis for determining the elasticity of demand and consummation of fish per capita in Serbia. Production and catch of fish in Serbia tended to increase during the observed period, with annual growth rate of 17.4%. Beside the fact that annual growth rate is 4.8%, fish consumption per capita in Serbia is still quite small (X=4.89kg, what is a consequence of population habit to consume predominantly meat. In our study we have found out that fish consumption in Serbia mostly depend on fish production per capita (rxy=0.6364, as well as on groos (rxy=0.6045 and net (rxy=0.5969 earnings. Also, it is determined that consumption elasticity has the highest growth in regard to fish production per capita. [Projekat Ministarstva nauke Republike Srbije, br. TR 31011

  14. Effects of copepod size on fish growth: A model based on data for North Sea sandeel

    DEFF Research Database (Denmark)

    Deurs, Mikael van; Jørgensen, C.; Fiksen, Ø.

    2015-01-01

    In productive marine off-shore ecosystems, the flow of energy from zooplankton to large predators is channeled through a few species of short-lived, highly abundant schooling planktivorous fish. There are indications that these species respond to qualitative and phenological changes...... in the zooplankton. If so, the climate-induced alterations of the local copepod communities that we see in temperate and arctic regions may influence the energy flux in marine food chains. In order to investigate how different processes contribute to the relationship between copepod size and fish growth, we merged 2...... was the most important factor, followed by handling time limitation and prey energy content. These limitations became stronger with increasing fish length, showing that copepod size and energy content have a strong effect on the specific growth potential of these fish...

  15. Multicistronic lentiviral vectors containing the FMDV 2A cleavage factor demonstrate robust expression of encoded genes at limiting MOI

    Directory of Open Access Journals (Sweden)

    Margison Geoffrey P

    2006-03-01

    Full Text Available Abstract Background A number of gene therapy applications would benefit from vectors capable of expressing multiple genes. In this study we explored the feasibility and efficiency of expressing two or three transgenes in HIV-1 based lentiviral vector. Bicistronic and tricistronic self-inactivating lentiviral vectors were constructed employing the internal ribosomal entry site (IRES sequence of encephalomyocarditis virus (EMCV and/or foot-and-mouth disease virus (FMDV cleavage factor 2A. We employed enhanced green fluorescent protein (eGFP, O6-methylguanine-DNA-methyltransferase (MGMT, and homeobox transcription factor HOXB4 as model genes and their expression was detected by appropriate methods including fluorescence microscopy, flow cytometry, immunocytochemistry, biochemical assay, and western blotting. Results All the multigene vectors produced high titer virus and were able to simultaneously express two or three transgenes in transduced cells. However, the level of expression of individual transgenes varied depending on: the transgene itself; its position within the construct; the total number of transgenes expressed; the strategy used for multigene expression and the average copy number of pro-viral insertions. Notably, at limiting MOI, the expression of eGFP in a bicistronic vector based on 2A was ~4 times greater than that of an IRES based vector. Conclusion The small and efficient 2A sequence can be used alone or in combination with an IRES for the construction of multicistronic lentiviral vectors which can express encoded transgenes at functionally relevant levels in cells containing an average of one pro-viral insert.

  16. Transport methods: general. 6. A Flux-Limited Diffusion Theory Derived from the Maximum Entropy Eddington Factor

    International Nuclear Information System (INIS)

    Yin, Chukai; Su, Bingjing

    2001-01-01

    The Minerbo's maximum entropy Eddington factor (MEEF) method was proposed as a low-order approximation to transport theory, in which the first two moment equations are closed for the scalar flux f and the current F through a statistically derived nonlinear Eddington factor f. This closure has the ability to handle various degrees of anisotropy of angular flux and is well justified both numerically and theoretically. Thus, a lot of efforts have been made to use this approximation in transport computations, especially in the radiative transfer and astrophysics communities. However, the method suffers numerical instability and may lead to anomalous solutions if the equations are solved by certain commonly used (implicit) mesh schemes. Studies on numerical stability in one-dimensional cases show that the MEEF equations can be solved satisfactorily by an implicit scheme (of treating δΦ/δx) if the angular flux is not too anisotropic so that f 32 , the classic diffusion solution P 1 , the MEEF solution f M obtained by Riemann solvers, and the NFLD solution D M for the two problems, respectively. In Fig. 1, NFLD and MEEF quantitatively predict very close results. However, the NFLD solution is qualitatively better because it is continuous while MEEF predicts unphysical jumps near the middle of the slab. In Fig. 2, the NFLD and MEEF solutions are almost identical, except near the material interface. In summary, the flux-limited diffusion theory derived from the MEEF description is quantitatively as accurate as the MEEF method. However, it is more qualitatively correct and user-friendly than the MEEF method and can be applied efficiently to various steady-state problems. Numerical tests show that this method is widely valid and overall predicts better results than other low-order approximations for various kinds of problems, including eigenvalue problems. Thus, it is an appealing approximate solution technique that is fast computationally and yet is accurate enough for a

  17. Clostridium botulinum in irradiated fish

    International Nuclear Information System (INIS)

    Hobbs, G.

    1977-01-01

    The properties of the Cl. botulinum resp. its toxin are described with a view to a combined heat and radiation treatment for fish conservation. The method is tested in several laboratories on 10 different fish products. It is found that the spore former Cl. botulinum is a critical factor in this type of preservation which can hardly be overcome although this method has organoleptic advantages over heat pasteurization of fish. At a storage temperatue over 5 0 C, there is a strong increase in toxin; the same applies to fish with a high fat content. Under poor hygienic conditions, the risk is markedly increased. The author recommends strict control measures in the production and distribution of fish, i.e. cooling and salt treatment. (AJ) [de

  18. Fish oil supplementation from 9 to 18 months of age affects the insulin-like growth factor axis in a sex-specific manner in Danish infants

    DEFF Research Database (Denmark)

    Damsgaard, Camilla T.; Harsløf, Laurine B. S.; Andersen, Anders D.

    2016-01-01

    Several studies have investigated the effects of fish oil (FO) on infant growth, but little is known about the effects of FO and sex on insulin-like growth factor-1 (IGF-1), the main regulator of growth in childhood. We explored whether FO v. sunflower oil (SO) supplementation from 9 to 18 months...... of age affected IGF-1 and its binding protein-3 (IGFBP-3) and whether the potential effects were sex specific. Danish infants (n 115) were randomly allocated to 5 ml/d FO (1·2 g/d n-3 long-chain PUFA (n-3 LCPUFA)) or SO. We measured growth, IGF-1, IGFBP-3 and erythrocyte EPA, a biomarker of n-3 LCPUFA...... intake and status, at 9 and 18 months. Erythrocyte EPA increased strongly with FO compared with SO (PIGF-1 in the total population, but a sex×group interaction (P=0·02). Baseline-adjusted IGF-1 at 18 months was 11·1 µg/l (95 % CI 0·4, 21·8;P=0...

  19. Oral vaccination of fish

    OpenAIRE

    Embregts, Carmen W.E.; Forlenza, Maria

    2016-01-01

    The limited number of oral vaccines currently approved for use in humans and veterinary species clearly illustrates that development of efficacious and safe oral vaccines has been a challenge not only for fish immunologists. The insufficient efficacy of oral vaccines is partly due to antigen breakdown in the harsh gastric environment, but also to the high tolerogenic gut environment and to inadequate vaccine design. In this review we discuss current approaches used to develop oral vaccines fo...

  20. Fish irradiation

    International Nuclear Information System (INIS)

    Kovacs, J.; Tengumnuay, C.; Juangbhanich, C.

    1970-01-01

    Chub-mackerel was chosen for the study because they are the most common fish in Thailand. Preliminary investigations were conducted to determine the maximum radiation dose of gamma-rays by organoleptic tests. The samples were subjected to radiation at various doses up to 4 Mrad. Many experiments were conducted using other kinds of fish. The results showed that 1 Mrad would be the maximum acceptable dose for fish. Later, the influence of the radiation dose from 0.1-1 Mrad was studied in order to find the optimum acceptable dose for preservation of fish without off-flavour. For this purpose, the Hedonic scale was used. It was found that 0.2 and 0.5 Mrad gave the best result on Chub mackerel. The determinations of optimum dose, organoleptic, microbiological and trimethylamine content changes were done. The results showed that Chub mackerel irradiated at 0.2, 0.5 and 1 Mrad stored at 3 0 C for 71 days were still acceptable, on the contrary the untreated samples were found unacceptable at 14 days. The trimethylamine increment was significantly higher in the untreated samples. At 15 days storage, trimethylamine in the non-irradiated Chub-mackerel was about 10 times higher than the irradiated ones. At 51 and 79 days storage, about 13 times higher in the control samples than the irradiated samples except 0.1 Mrad. Only 2 times higher was found for the 0.1 Mrad. The microbiological results showed that the irradiation above 0.2 Mrad gave favorable extension of shelf-life of fish

  1. Consumers Analysis Towards Fish Consumption, and its Related Factors, Barriers of Consumption and Promotion Strategies using Social Marketing frame work among women in Yazd city in 2013

    Directory of Open Access Journals (Sweden)

    H Rezaeipandari

    2014-09-01

    Results: Housewives and employed women reported similar and sometimes different barriers for fish consumption. The barriers for non consumption were of the following: high price of fish, unpleasant taste of fish, having bone and goo, and dislike of fish by one of the family members. From the viewpoint of the employed women, being unfamiliar with cooking methods(promotion aspect, high price of fish, unpleasant taste of fish, having bone and goo, its favor, dislike of fish by one of the family members, and lack of time were reported as the most important barriers. Conclusion: People's views, demands and preferences about different issues and products such as health issues and healthy products are influenced by individual and environmental conditions including biologic condition and health level, cultural, social, political, economic and bio-environmental conditions which can be affected by time and by changing these conditions. Therefore, social marketing framework should emphasize on the need for a comprehensive and proper understanding of consumers of each product and categorize them by their differences in planning and implementing social marketing programs. Thus one can be certain that intervention programs reach more appropriate consumers and cause desired consumption behavior changes

  2. Microbiological spoilage of fish and fish products

    DEFF Research Database (Denmark)

    Gram, Lone; Huss, Hans Henrik

    1996-01-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative...... biochemical indicators of spoilage. Shewanzella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram......- positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish...

  3. Tenax extraction for exploring rate-limiting factors in methyl-β-cyclodextrin enhanced anaerobic biodegradation of PAHs under denitrifying conditions in a red paddy soil

    International Nuclear Information System (INIS)

    Sun, Mingming; Ye, Mao; Hu, Feng; Li, Huixin; Teng, Ying; Luo, Yongming; Jiang, Xin; Kengara, Fredrick Orori

    2014-01-01

    Highlights: • Enhanced anaerobic bioremediation of a red paddy soil polluted with PAHs. • 1% (w/w) methyl-β-cyclodextrin (MCD) and 20 mM nitrate addition acted as solubility-enhancing agent and electron acceptor respectively. • Tenax extraction and a first-three-compartment modeling were applicable to explore the rate-limiting factors in the biodegradation. • Lack of PAH-degraders hindered biodegradation in control and MCD addition treatments. • Inadequate bioaccessible PAHs was vital rate-limiting factor in nitrate addition treatments. -- Abstract: The effectiveness of anaerobic bioremediation systems for PAH-contaminated soil may be constrained by low contaminants bioaccessibility due to limited aqueous solubility and lack of suitable electron acceptors. Information on what is the rate-limiting factor in bioremediation process is of vital importance in the decision in what measures can be taken to assist the biodegradation efficacy. In the present study, four different microcosms were set to study the effect of methyl-β-cyclodextrin (MCD) and nitrate addition (N) on PAHs biodegradation under anaerobic conditions in a red paddy soil. Meanwhile, sequential Tenax extraction combined with a first-three-compartment model was employed to evaluate the rate-limiting factors in MCD enhanced anaerobic biodegradation of PAHs. Microcosms with both 1% (w/w) MCD and 20 mM N addition produced maximum biodegradation of total PAHs of up to 61.7%. It appears rate-limiting factors vary with microcosms: low activity of degrading microorganisms is the vital rate-limiting factor for control and MCD addition treatments (CK and M treatments); and lack of bioaccessible PAHs is the main rate-limiting factor for nitrate addition treatments (N and MN treatments). These results have practical implications for site risk assessment and cleanup strategies

  4. Tenax extraction for exploring rate-limiting factors in methyl-β-cyclodextrin enhanced anaerobic biodegradation of PAHs under denitrifying conditions in a red paddy soil

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Mingming, E-mail: sunmingming@njau.edu.cn [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Key Laboratory of Soil Environmental and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Ye, Mao [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Hu, Feng, E-mail: fenghu@njau.edu.cn [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Li, Huixin [Soil Ecology Lab, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Teng, Ying [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Luo, Yongming [Yantai Institute of Costal Zone Research, Chinese Academy of Sciences, Yantai 264003 (China); Jiang, Xin [State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008 (China); Kengara, Fredrick Orori [Department of Chemistry, Maseno University, Private Bag, Maseno 40105 (Kenya)

    2014-01-15

    Highlights: • Enhanced anaerobic bioremediation of a red paddy soil polluted with PAHs. • 1% (w/w) methyl-β-cyclodextrin (MCD) and 20 mM nitrate addition acted as solubility-enhancing agent and electron acceptor respectively. • Tenax extraction and a first-three-compartment modeling were applicable to explore the rate-limiting factors in the biodegradation. • Lack of PAH-degraders hindered biodegradation in control and MCD addition treatments. • Inadequate bioaccessible PAHs was vital rate-limiting factor in nitrate addition treatments. -- Abstract: The effectiveness of anaerobic bioremediation systems for PAH-contaminated soil may be constrained by low contaminants bioaccessibility due to limited aqueous solubility and lack of suitable electron acceptors. Information on what is the rate-limiting factor in bioremediation process is of vital importance in the decision in what measures can be taken to assist the biodegradation efficacy. In the present study, four different microcosms were set to study the effect of methyl-β-cyclodextrin (MCD) and nitrate addition (N) on PAHs biodegradation under anaerobic conditions in a red paddy soil. Meanwhile, sequential Tenax extraction combined with a first-three-compartment model was employed to evaluate the rate-limiting factors in MCD enhanced anaerobic biodegradation of PAHs. Microcosms with both 1% (w/w) MCD and 20 mM N addition produced maximum biodegradation of total PAHs of up to 61.7%. It appears rate-limiting factors vary with microcosms: low activity of degrading microorganisms is the vital rate-limiting factor for control and MCD addition treatments (CK and M treatments); and lack of bioaccessible PAHs is the main rate-limiting factor for nitrate addition treatments (N and MN treatments). These results have practical implications for site risk assessment and cleanup strategies.

  5. Fish Remains from Excavations near the Riverfront at Newcastle upon Tyne, England

    Directory of Open Access Journals (Sweden)

    Rebecca A. Nicholson

    1997-12-01

    Full Text Available The City of Newcastle, situated some 10 miles inland on the River Tyne in north-east England, is not now an important fishing port. Most of the fresh fish marketed in the city has been landed at the nearby coastal ports of North and South Shields. Excavations at two sites behind the present Quayside in Newcastle, however, have yielded quantities of fish bones, representing a wide variety of species. This is in contrast to excavations in other parts of the city, where few fish remains have been recovered, and suggests that the quayside in Newcastle was an important centre for the fishing industry during the medieval period. It seems likely that most of the fish remains represent waste from landing and processing fish on or near the quayside. Yet, when taphonomic factors are taken into account, the limitations of using even large bone assemblages to interpret processing activities is demonstrated. As always, the need for a programme of on-site sieving to obtain representative samples of fish bone is evident.

  6. Motives, barriers and quality evaluation in fish consumption situations

    DEFF Research Database (Denmark)

    Brunsø, Karen; Verbeke, Wim; Olsen, Svein Ottar

    2009-01-01

    and user groups with respect to preparation skills and the use of quality cues. Heavy users are very skilled in evaluating fish quality, especially those in Spain, while light users, especially those in Belgium, make seemingly irrational assumptions when evaluating the quality of fish. Research limitations...... research into explaining variations in fish consumption, as well as for fish quality evaluation and fish market segmentation studies....

  7. Limit of detection and threshold for positivity of the Centers for Disease Control and Prevention assay for factor VIII inhibitors.

    Science.gov (United States)

    Miller, C H; Boylan, B; Shapiro, A D; Lentz, S R; Wicklund, B M

    2017-10-01

    Essentials Immunologic methods detect factor VIII (FVIII) antibodies in some inhibitor-negative specimens. Specimens were tested by modified Nijmegen-Bethesda assay (NBA) and fluorescence immunoassay. The NBA with preanalytical heat inactivation detects FVIII inhibitors down to 0.2 NBU. IgG 4 frequency validates the established threshold for positivity of ≥ 0.5 NBU for this NBA. Background The Bethesda assay for measurement of factor VIII inhibitors called for quantification of positive inhibitors by using dilutions producing 25-75% residual activity (RA), corresponding to 0.4-2.0 Bethesda units, with the use of 'more sensitive methods' for samples with RA closer to 100% being recommended. The Nijmegen modification (Nijmegen-Bethesda assay [NBA]) changed the reagents used but not these calculations. Some specimens negative by the NBA have been shown to have FVIII antibodies detectable with sensitive immunologic methods. Objective To examine the performance at very low inhibitor titers of the Centers for Disease Control and Prevention (CDC)-modified NBA (CDC-NBA), which includes preanalytic heat inactivation to liberate bound anti-FVIII antibodies. Methods Specimens with known inhibitors were tested with the CDC-NBA. IgG 4 anti-FVIII antibodies were measured by fluorescence immunoassay (FLI). Results Diluted inhibitors showed linearity below 0.4 Nijmegen-Bethesda units (NBU). With four statistical methods, the limit of detection of the CDC-NBA was determined to be 0.2 NBU. IgG 4 anti-FVIII antibodies, which correlate most strongly with functional inhibitors, were present at rates above the background rate of healthy controls in specimens with titers ≥ 0.2 NBU and showed an increase in frequency from 14.3% at 0.4 NBU to 67% at the established threshold for positivity of 0.5 NBU. Conclusions The CDC-NBA can detect inhibitors down to 0.2 NBU. The FLI, which is more sensitive, demonstrates anti-FVIII IgG 4 in some patients with negative (NBA, supporting the need for

  8. 3D conformal radiation therapy and hormonal therapy for localized prostate cancer: Is age a limiting factor?

    International Nuclear Information System (INIS)

    Faure, A.; Negrea, T.; Lechevallier, E.; Coulange, C.; Murraciole, X.; Jouvea, E.; Sambuca, R.; Cowen, D.

    2011-01-01

    No study on side effects had showed that conformal radiation therapy for prostate cancer is more harmful in patients older than 70 years to patients younger. The aim of this study was to evaluate acute and late toxicities of conformal radiotherapy, with high dose for localized prostate cancer in patients older than 70 years and compared to patients younger than 70 years. Between 1996 and 2009, 104 patients were treated with radiation therapy and hormonal therapy for localized cancer prostate. Median follow-up was 105 months (9 300). Acute (occurred at ≤ three months) and late side effects of 55 patients older than 70 years (median age: 75 [71 92]) were graded according to the CTCAE 3.0 criteria and compared to the younger population. Median dose to the prostate was 75.6 Gy (67 80) in both groups. There were no significant differences in acute and late side effects between age groups. For patients above 70 years, the incidence of grade II or higher acute and late side effects were respectively 27 and 22% for urologic symptoms and 13 and 16% for rectal symptoms. The frequency of grade III late symptoms was low and ranged between 0 and 6% for the evaluated symptoms, irrespective of age group. Older patients had a better biochemical recurrence-free survival than younger patients (86 versus 77% at four years, P ≡ ns). High dose 3D conformal radiotherapy for localized prostate cancer was well tolerated in patients older than 70 years. Age is not a limiting factor for conformal radiation therapy and hormonotherapy for older patients. (authors)

  9. Fish gelatin.

    Science.gov (United States)

    Boran, Gokhan; Regenstein, Joe M

    2010-01-01

    Gelatin is a multifunctional ingredient used in foods, pharmaceuticals, cosmetics, and photographic films as a gelling agent, stabilizer, thickener, emulsifier, and film former. As a thermoreversible hydrocolloid with a narrower gap between its melting and gelling temperatures, both of which are below human body temperature, gelatin provides unique advantages over carbohydrate-based gelling agents. Gelatin is mostly produced from pig skin, and cattle hides and bones. Some alternative raw materials have recently gained attention from both researchers and the industry not just because they overcome religious concerns shared by Jews and Muslims but also because they provide, in some cases, technological advantages over mammalian gelatins. Fish skins from a number of fish species are among the other sources that have been comprehensively studied as sources for gelatin production. Fish skins have a significant potential for the production of high-quality gelatin with different melting and gelling temperatures over a much wider range than mammalian gelatins, yet still have a sufficiently high gel strength and viscosity. Gelatin quality is industrially determined by gel strength, viscosity, melting or gelling temperatures, the water content, and microbiological safety. For gelatin manufacturers, yield from a particular raw material is also important. Recent experimental studies have shown that these quality parameters vary greatly depending on the biochemical characteristics of the raw materials, the manufacturing processes applied, and the experimental settings used for quality control tests. In this review, the gelatin quality achieved from different fish species is reviewed along with the experimental procedures used to determine gelatin quality. In addition, the chemical structure of collagen and gelatin, the collagen-gelatin conversion, the gelation process, and the gelatin market are discussed. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Fish Immunoglobulins

    OpenAIRE

    Sara Mashoof; Michael F. Criscitiello

    2016-01-01

    The B cell receptor and secreted antibody are at the nexus of humoral adaptive immunity. In this review, we summarize what is known of the immunoglobulin genes of jawed cartilaginous and bony fishes. We focus on what has been learned from genomic or cDNA sequence data, but where appropriate draw upon protein, immunization, affinity and structural studies. Work from major aquatic model organisms and less studied comparative species are both included to define what is the rule for an immunoglob...

  11. Fish cognition

    OpenAIRE

    Bshary, Redouan; Brown, Culum

    2017-01-01

    The central nervous system, and the brain in particular, is one of the most remarkable products of evolution. This system allows an individual to acquire, process, store and act on information gathered from the environment. The resulting flexibility in behavior beyond genetically coded strategies is a prime adaptation in animals. The field of animal cognition examines the underlying processes and mechanisms. Fishes are a particularly interesting group of vertebrates to study cognition for two...

  12. Fish hemoglobins

    OpenAIRE

    Souza,P.C. de; Bonilla-Rodriguez,G.O.

    2007-01-01

    Vertebrate hemoglobin, contained in erythrocytes, is a globular protein with a quaternary structure composed of 4 globin chains (2 alpha and 2 beta) and a prosthetic group named heme bound to each one. Having myoglobin as an ancestor, hemoglobin acquired the capacity to respond to chemical stimuli that modulate its function according to tissue requirements for oxygen. Fish are generally submitted to spatial and temporal O2 variations and have developed anatomical, physiological and biochemica...

  13. Fish eye optics

    Czech Academy of Sciences Publication Activity Database

    Hudec, René; Michalová, S.

    2017-01-01

    Roč. 47, č. 2 (2017), s. 94-99 ISSN 1335-1842. [INTEGRAL/BART Workshop /14./. Karlovy Vary, 03.04.2017-07.04.2017] Grant - others:GA ČR(CZ) GA13-33324S Institutional support: RVO:67985815 Keywords : fish eye optics * lobster eye optics * X-ray monitoring Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics OBOR OECD: Astronomy (including astrophysics,space science) Impact factor: 0.336, year: 2016

  14. Shake and stew: a non-destructive PCR-ready DNA isolation method from a single preserved fish larva.

    Science.gov (United States)

    Alvarado Bremer, J R; Smith, B L; Moulton, D L; Lu, C-P; Cornic, M

    2014-01-01

    A rapid non-destructive alternative to isolate DNA from an individual fish larva is presented, based on the suspension of epithelial cells through vortex forces, and the release of DNA in a heated alkaline solution. DNA from >6056 fish larvae isolated using this protocol has yielded a high PCR amplification success rate (>93%), suggesting its applicability to other taxonomic groups or sources when tissue amount is the limiting factor. © 2014 The Fisheries Society of the British Isles.

  15. Pharmaceuticals in water, fish and osprey nestlings in Delaware River and Bay

    Science.gov (United States)

    Bean, Thomas G.; Rattner, Barnett A.; Lazarus, Rebecca S.; Day, Daniel D.; Burket, S. Rebekah; Brooks, Bryan W.; Haddad, Samuel P.; Bowerman, William W.

    2018-01-01

    Exposure of wildlife to Active Pharmaceutical Ingredients (APIs) is likely to occur but studies of risk are limited. One exposure pathway that has received attention is trophic transfer of APIs in a water-fish-osprey food chain. Samples of water, fish plasma and osprey plasma were collected from Delaware River and Bay, and analyzed for 21 APIs. Only 2 of 21 analytes exceeded method detection limits in osprey plasma (acetaminophen and diclofenac) with plasma levels typically 2–3 orders of magnitude below human therapeutic concentrations (HTC). We built upon a screening level model used to predict osprey exposure to APIs in Chesapeake Bay and evaluated whether exposure levels could have been predicted in Delaware Bay had we just measured concentrations in water or fish. Use of surface water and BCFs did not predict API concentrations in fish well, likely due to fish movement patterns, and partitioning and bioaccumulation uncertainties associated with these ionizable chemicals. Input of highest measured API concentration in fish plasma combined with pharmacokinetic data accurately predicted that diclofenac and acetaminophen would be the APIs most likely detected in osprey plasma. For the majority of APIs modeled, levels were not predicted to exceed 1 ng/mL or method detection limits in osprey plasma. Based on the target analytes examined, there is little evidence that APIs represent a significant risk to ospreys nesting in Delaware Bay. If an API is present in fish orders of magnitude below HTC, sampling of fish-eating birds is unlikely to be necessary. However, several human pharmaceuticals accumulated in fish plasma within a recommended safety factor for HTC. It is now important to expand the scope of diet-based API exposure modeling to include alternative exposure pathways (e.g., uptake from landfills, dumps and wastewater treatment plants) and geographic locations (developing countries) where API contamination of the environment may represent greater risk.

  16. Fish hemoglobins

    Directory of Open Access Journals (Sweden)

    P.C. de Souza

    2007-06-01

    Full Text Available Vertebrate hemoglobin, contained in erythrocytes, is a globular protein with a quaternary structure composed of 4 globin chains (2 alpha and 2 beta and a prosthetic group named heme bound to each one. Having myoglobin as an ancestor, hemoglobin acquired the capacity to respond to chemical stimuli that modulate its function according to tissue requirements for oxygen. Fish are generally submitted to spatial and temporal O2 variations and have developed anatomical, physiological and biochemical strategies to adapt to the changing environmental gas availability. Structurally, most fish hemoglobins are tetrameric; however, those from some species such as lamprey and hagfish dissociate, being monomeric when oxygenated and oligomeric when deoxygenated. Fish blood frequently possesses several hemoglobins; the primary origin of this finding lies in the polymorphism that occurs in the globin loci, an aspect that may occasionally confer advantages to its carriers or even be a harmless evolutionary remnant. On the other hand, the functional properties exhibit different behaviors, ranging from a total absence of responses to allosteric regulation to drastic ones, such as the Root effect.

  17. Resource partitioning within major bottom fish species in a highly productive upwelling ecosystem

    Science.gov (United States)

    Abdellaoui, Souad; El Halouani, Hassan; Tai, Imane; Masski, Hicham

    2017-09-01

    The Saharan Bank (21-26°N) is a wide subtropical continental shelf and a highly productive upwelling ecosystem. The bottom communities are dominated by octopus and sparid fish, which are the main targets of bottom-trawl fishing fleets. To investigate resource partitioning within the bottom fish community, adult fish from 14 of the most abundant species were investigated for stomach content analysis. Samples were collected during two periods: October 2003 and May 2007. The diet of the analysed species showed more variation between periods than between size classes, suggesting that temporal or spatial variability in prey availability appears to play a significant role in their diet. Multivariate analysis and subsequent clustering led to a grouping of the species within five trophic guilds. Two species were fish feeders, and the others mainly fed on benthic invertebrates, where epibenthic crustaceans, lamellibranchs and fish were the most important groups in defining trophic guilds. We found that the studied species had a high rate of overlapping spatial distributions and overlapping trophic niches. In this highly productive upwelling ecosystem, where food resources may not be a limiting factor, inter-specific competition did not appear to be an important factor in structuring bottom fish communities. For the species that showed differences in the proportions of prey categories in comparison with other ecosystems, the rise of the proportion of epibenthic crustaceans in their diet was a common feature; a possible consequence of the benthic productivity of this highly productive upwelling ecosystem.

  18. Bull trout life history, genetics, habitat needs, and limiting factors in central and northeast Oregon, Annual Report 1995

    International Nuclear Information System (INIS)

    Hemmingsen, A.R.; Buchanan, D.V.; Howell, P.J.

    1996-03-01

    To fulfill one objective of the present study, genetic characteristics of Oregon bull trout will be determined by analysis of mitochondrial and nuclear DNA. During 1995, the authors collected and sampled a total of 1,217 bull trout from 46 streams in the Columbia River Basin. DNA analysis of those samples will be conducted at University of Montana. They primarily sampled juvenile fish near natal areas to increase the likelihood of identifying discrete populations while minimizing risk of injury to large spawners. Fork lengths of all fish sampled ranged from 2.6 to 60.5 cm with a median of 12 cm. Eighty-four percent of all bull trout sampled were less than 19 cm while two percent were larger than 27 cm. Bull trout were collected by several methods, mostly by electrofishing. Eighty-six percent of all bull trout sampled were collected by electrofishing with a programmable waveform electrofisher. They observed injuries caused by electrofishing to 8% of that proportion. Based on preliminary analysis, no waveform combination used appeared less injurious than others. Highest voltages appeared less injurious than some that were lower. Frequency of electrofishing injury was significantly correlated to fork length over the range-from 4 to 26 cm. There were indications for substantial risk for such injury to bull trout larger than 26 cm. Other species found in association with bull trout included chinook salmon Oncorhynchus tshawytscha, mountain whitefish Prosopium williamsoni, rainbow trout Oncorhynchus mykiss, sculpins Cottus spp., cutthroat trout Oncorhynchus clarki, non-native brook trout Salvelinus fontinalis, and tailed frogs Ascaphus truei. Rainbow trout was the species most frequently associated with bull trout. No injury or mortality was observed for any of the associated species captured

  19. Invasion of parasitic isopods in marine fishes

    Directory of Open Access Journals (Sweden)

    Ganapathy Rameshkumar

    2013-02-01

    Full Text Available Objective: To carry out a detailed three-year observation study on isopod parasites infestation in fish. Methods: Fish samples were collected from different localities in various landing centers along the Tamil Nadu coastal area. The prevalence and mean intensity were calculated. The proximate composition of infestation and uninfestation were studied in different marine fishes. A comparative analysis of bacteria and fungi in the infected and uninfected regions of fishes were analysed. Results: Tweenty six species including 12 genera of isopods (Cymothoidae distributed in 39 species of marine fishes along the Tamil Nadu coast. The isopod parasites were attached in three different microhabitats in host fishes viz. , buccal, branchial and body surfaces. They exhibited host and site specific occurrence. Maximum prevalence 17.11% was recorded in March 2010 and minimum 0.27% in Febuary 2010. The intensity ranged from 1 to 1.7 parasites per fish during the different months from Decmber 2008 to November 2011. There was a decrease in the protein, carbohydrate and lipid content in the infested fishes compared to uninfected fishes. A comparative analysis of bacteria and fungi in the infected and uninfected region of fishes were analysed. It revealed that infected portions had dense bacterial load as observed in the lesions of infected fishes than uninfected fishes. Conclusion: Factors which are able to induce parasitic manifestation are stock quality, stocking density, environmental conditions, biological and physiological characteristics of parasite, zoo technical measures, food quantity, feeding strategies, etc.

  20. Stable carbon and nitrogen isotope trophic enrichment factors for Steller sea lion vibrissae relative to milk and fish/invertebrate diets

    Science.gov (United States)

    Stricker, Craig A.; Christ, Aaron M.; Wunder, Michael B.; Doll, Andrew C.; Farley, Sean D.; Rea, Lorrie D.; Rosen, David A. S.; Scherer, R. D.; Tollit, Dominic J.

    2015-01-01

    Nutritional constraints have been proposed as a contributor to population declines in the endangered Steller sea lion Eumetopias jubatus in some regions of the North Pacific. Isotopic analysis of vibrissae (whiskers) is a potentially useful approach to resolving the nutritional ecology of this species because long-term (up to 8 yr) dietary information is sequentially recorded and metabolically inert once formed. Additionally, vibrissae are grown in utero, potentially offering indirect inference on maternal diet. However, diet reconstruction using isotopic techniques requires a priori knowledge of trophic enrichment factors (TEFs), which can vary relative to diet quality and among animal species. In this study, we provide new TEF estimates for (1) maternal relative to pup vibrissae during both gestation and nursing and (2) adult vibrissae relative to a complex diet. Further, we refine vibrissa-milk TEFs based on an additional 76 animals with an age distribution ranging from 1 to 20 mo. Mother-pup vibrissae TEF values during gestation and nursing were near zero for δ13C and averaged 0.8 and 1.6‰, respectively, for δ15N. In contrast, vibrissa-fish/invertebrate TEFs averaged 3.3 (± 0.3 SD) and 3.7‰ (±0.3) for lipid-free δ13C and δ15N, respectively. Average lipid-free δ13C and δ15N vibrissa-milk TEFs were 2.5 (±0.9) and 1.8‰ (±0.8), respectively, and did not differ among metapopulations. Empirically determined TEFs are critical for accurate retrospective diet modeling, particularly for evaluating the hypothesis of nutritional deficiency contributing to the lack of Steller sea lion population recovery in some regions of Alaska.

  1. Fishery status, growth, reproduction biology and feeding habit of two scombrid fish from the Gulf of Aqaba, Red Sea

    International Nuclear Information System (INIS)

    Al-Zibdah, M.; Odat, N.

    2007-01-01

    The fishery and some biological aspects of two Scombrid fish species, Katsuwonus pelamis and Euthynnus affinis from the Gulf of Aqaba were studied during one year period (1999-2000). Monthly samples of the two species were collected to investigate growth, reproduction and feeding habit. Results showed that the Scombridae family form more than 60% of the total catch of Jordanian fishery. The length-weight relationships (LWr) in the two fish species demonstrated thatthe growth is of an allometric type (around 3). The condition factor (k) showed relatively consistent values in both species but revealed slight variability in growth periods. This could be attributed to the limited food availability in fish natural habitat. Different age classes were observed in the catch of the two species irrespective of season. The mean GSI exhibited similar change pattern with season in both sexes of the two fish. Spawning behavior and planktonic larvae of both fish were not observed in the field. This could be inferred that these fish are not migrating to the region for reproduction. The food composition of K. pelamis and E. affinis suggests that the fish compete for the same food items. These are the fish At herinomorous lacunosus, crustacean and molluscans. Prey occurrence in fish stomachs is attributed mainly to the seasonal availability of food in the Gulf of Aqaba. High abundance of food items in winter may indicate that the two species migrate at the climax of primary productivity in the Gulf. (author)

  2. Contribution of central and peripheral factors at peak exercise in heart failure patients with progressive severity of exercise limitation.

    Science.gov (United States)

    Del Torto, Alberico; Corrieri, Nicoletta; Vignati, Carlo; Gentile, Piero; Cattadori, Gaia; Paolillo, Stefania; Agostoni, Piergiuseppe

    2017-12-01

    A reduced cardiac output (CO) response during exercise is a major limiting factor in heart failure (HF). Oxygen consumption (VO 2 ) is directly proportional to CO. Peripheral mechanisms via arteriovenous oxygen difference (Δ(a-v)O 2 ) play a pivotal role in chronic HF. We hypothesized a weak correlation between peak VO 2 and peak CO with a greater Δ(a-v)O 2 variability in most severe HF. We analyzed 278 HF patients (NYHA II-III) who performed maximal cardiopulmonary exercise test with non-invasive CO measurement by inert gas rebreathing. Median peakVO 2 , CO and Δ(a-v)O 2 were 0.96 (0.78-1.28) L/min, 6.3 (5.1-8.0) L/min and 16.0 (14.2-18.0) mL/100mL respectively, with a linear relationship between VO 2 and CO: CO=5.3×VO 2 +1.13 (r 2 =0.705, pexercise limitation. Group 1 (101 patients) peakVO 2 <50% pred: peakVO 2 0.80 (0.67-0.94) L/min, peakCO 5.6 (4.7-6.5) L/min, peakΔ(a-v)O 2 14.8 (12.9-17.1) mL/100mL. Group 2 (89 patients) peakVO 2 ≥50-<65% pred: peakVO 2 1.02 (0.84-1.29) L/min, peakCO 6.4 (5.1-8.0) L/min, peakΔ(a-v)O 2 16.7 (15.0-18.5) mL/100mL. Group 3 (88 patients) peakVO 2 ≥65% pred: peakVO 2 1.28 (0.93-1.66) L/min, peakCO 8.0 (6.2-9.7) L/min, peakΔ(a-v)O 2 16.8 (14.6-18.3) mL/100mL. A peakVO 2 and peakCO linear relationship was observed in Group 1 (r 2 =0.381, p<0.001), Group 2 (r 2 =0.756, p<0.001) and Group 3 (r 2 =0.744, p<0.001). With worsening HF we observed a progressive reduction of peak CO and peak VO 2 . However in most compromised patients also peripheral mechanisms play a role as indicated by reduced Δ(a-v)O 2 . Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Recent population size, trends, and limiting factors for the double-crested Cormorant in Western North America

    Science.gov (United States)

    Adkins, Jessica Y.; Roby, Daniel D.; Lyons, Donald E.; Courtot, Karen N.; Collis, Ken; Carter, Harry R.; Shuford, W. David; Capitolo, Phillip J.

    2014-01-01

    colonies by bald eagles (Haliaeetus leucocephalus) and humans are likely limiting factors on the growth of the western population at present. Because of differences in biology and management, the western population of double-crested cormorants warrants consideration as a separate management unit from the population east of the Continental Divide.

  4. Who cares about fish welfare?

    DEFF Research Database (Denmark)

    Ellingsen, Kristian; Grimsrud, Kristine; Nielsen, Hanne Marie

    2015-01-01

    . Research limitations/implications – In this study willingness to pay is measured using a hypothetical choice experiment. Values people express as citizens, however, may not accurately predict true consumer behaviour. This is generally referred to as “citizen-consumer duality” and may have affected...... about the appropriate way to pay for better welfare standards in fish production. Design/methodology/approach – On the basis of two focus group sessions, a survey questionnaire was developed and distributed to a representative sample of 2,147 Norwegian households via e-mail. Findings – Results showed...... the results. Practical implications – The study shows that there is a national market for welfare-assured fish products, but education initiatives focusing on fish farming and fish welfare issues would further influence the attitudes and purchasing habits of Norwegian consumers. Originality/value – Although...

  5. Identification of orange-spotted grouper (Epinephelus coioides) interferon regulatory factor 3 involved in antiviral immune response against fish RNA virus.

    Science.gov (United States)

    Huang, Youhua; Huang, Xiaohong; Cai, Jia; OuYang, Zhengliang; Wei, Shina; Wei, Jingguang; Qin, Qiwei

    2015-02-01

    Interferon regulatory factor 3 (IRF3) is an important transcription factor which regulates the expression of interferon (IFN) and IFN-stimulated genes (ISGs) following virus recognition. In this study, a novel IRF3 gene was cloned from grouper Epinephelus coioides (EcIRF3) and its effects against Singapore grouper iridovirus (SGIV) and red spotted grouper nervous necrosis virus (RGNNV) was investigated. The full-length of EcIRF3 cDNA was composed of 2513 bp and encoded a polypeptide of 458 amino acids which shared 82% identity with European seabass (Dicentrarchus labrax). EcIRF3 contained three conserved domains including a DNA-binding domain (DBD), an IRF associated domain (IAD) and a serine-rich domain. Expression profile analysis revealed that EcIRF3 was abundant in head kidney, kidney, spleen and gill. Upon different stimuli in vitro, the transcript of EcIRF3 was significantly up-regulated after RGNNV infection or treatment with polyinosin-polycytidylic acid (poly I:C). During SGIV infection, the increase of the EcIRF3 transcription was only detected at the late stage, suggesting that EcIRF3 was differently regulated by different stimuli. Immune fluorescence assay indicated that the fluorescence signal of EcIRF3 was increased significantly after infection with RGNNV or treatment with poly I:C, but moderately at the late stage of SGIV infection. Reporter gene assay showed that EcIRF3 activated zebrafish type I IFN and type III IFN promoter in vitro. The viral gene transcription and virus production of RGNNV were significantly decreased in EcIRF3 overexpressing cells. However, the ectopic expression of EcIRF3 did not affect the gene transcription and virus production of SGIV. Moreover, the mRNA expression levels of type I IFN and IFN-inducible genes (MxI, ISG15 and ISG56) were increased in RGNNV infected EcIRF3 overexpressing cells compared to empty vector transfected cells. Together, our results demonstrated that IFN immune response mediated by grouper IRF3 was

  6. Wild-Caught Versus Farmed Fish – Consumer Perception

    Directory of Open Access Journals (Sweden)

    Tomić Marina

    2017-06-01

    Full Text Available We have limited knowledge of determinants of consumer preferences for wild-caught versus farmed-raised fish, so this work aims to investigate the impact of sociodemographics, habits and frequency of fresh fish consumption, such as involvement in cooking, on the preferences for wild versus farmed fish. A survey was done on a sample of 1151 fish consumers in Croatia. Results showed that female, older consumers, consumers with higher income and those living in coastal parts of Croatia give higher preferences for wild fish and they detect differences between the taste of wild and farmed fish. Consumers with higher levels of habits of fresh fish consumption, who eat fresh fish often and are more involved in cooking, prefer wild-caught fish. These findings provide valuable information for the aquaculture sector, especially for planning marketing strategies for the promotion of farmed fish.

  7. UV filters bioaccumulation in fish from Iberian river basins.

    Science.gov (United States)

    Gago-Ferrero, Pablo; Díaz-Cruz, M Silvia; Barceló, Damià

    2015-06-15

    The occurrence of eight organic UV filters (UV-Fs) was assessed in fish from four Iberian river basins. This group of compounds is extensively used in cosmetic products and other industrial goods to avoid the damaging effects of UV radiation, and has been found to be ubiquitous contaminants in the aquatic ecosystem. In particular, fish are considered by the scientific community to be the most feasible organism for contamination monitoring in aquatic ecosystems. Despite that, studies on the bioaccumulation of UV-F are scarce. In this study fish samples from four Iberian river basins under high anthropogenic pressure were analysed by liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Benzophenone-3 (BP3), ethylhexyl methoxycinnamate (EHMC), 4-methylbenzylidene camphor (4MBC) and octocrylene (OC) were the predominant pollutants in the fish samples, with concentrations in the range of ng/g dry weight (d.w.). The results indicated that most polluted area corresponded to Guadalquivir River basin, where maximum concentrations were found for EHMC (241.7 ng/gd.w.). Sediments from this river basin were also analysed. Lower values were observed in relation to fish for OC and EHMC, ranging from below the limits of detection to 23 ng/gd.w. Accumulation levels of UV-F in the fish were used to calculate biota-sediment accumulation factors (BSAFs). These values were always below 1, in the range of 0.04-0.3, indicating that the target UV-Fs are excreted by fish only to some extent. The fact that the highest concentrations were determined in predators suggests that biomagnification of UV-F may take place along the freshwater food web. Copyright © 2015. Published by Elsevier B.V.

  8. Fish Tales

    International Nuclear Information System (INIS)

    McLerran, L.

    2010-01-01

    This talk is about fishing and the friendships that have resulted in its pursuit. It is also about theoretical physics, and the relationship of imagination and fantasy to the establishment of ideas about nature. Fishermen, like theoretical physicists, are well known for their inventive imaginations. Perhaps neither are as clever as sailors, who conceived of the mermaid. If one doubts the power of this fantasy, one should remember the ghosts of the many sailors who drowned pursuing these young nymphs. An extraordinary painting by J. Waterhouse is shown as Fig. 1. The enchantment of a mermaid must reflect an extraordinary excess of imagination on the part of the sailor, perhaps together with an impractical turn of mind. A consummated relationship with a mermaid is after all, by its very nature a fantasy incapable of realization. To a theoretical physicist, she is symbolic of many ideas we develop. There are many truths known to fisherman in which one might also find parallels to the goals of scientists: (1) A fish is the only animal that keeps growing after its death; (2) Nothing makes a fish bigger than almost being caught; (3) ''...of all the liars among mankind, the fisherman is the most trustworthy.'' (William Sherwood Fox, in Silken Lines and Silver Hooks); and (4) Men and fish are alike. They both get into trouble when they open their mouths. These quotes may be interpreted as reflecting skepticism regarding the honesty of fisherman, and probably do not reflect adequate admiration for a creative imagination. Is it fair to criticize a person for believing a falsehood that he or she sincerely believes to be true? The fisherman simultaneously invents the lie, and believes in it himself. The parallel with theoretical physics is perhaps only approximate, although we physicists may invent stories that we come to believe, on some rare occasions our ideas actually correspond to a more or less true descriptions of nature. These minor philosophical differences are not

  9. Fish Tales

    Energy Technology Data Exchange (ETDEWEB)

    McLerran, L.

    2010-07-06

    This talk is about fishing and the friendships that have resulted in its pursuit. It is also about theoretical physics, and the relationship of imagination and fantasy to the establishment of ideas about nature. Fishermen, like theoretical physicists, are well known for their inventive imaginations. Perhaps neither are as clever as sailors, who conceived of the mermaid. If one doubts the power of this fantasy, one should remember the ghosts of the many sailors who drowned pursuing these young nymphs. An extraordinary painting by J. Waterhouse is shown as Fig. 1. The enchantment of a mermaid must reflect an extraordinary excess of imagination on the part of the sailor, perhaps together with an impractical turn of mind. A consummated relationship with a mermaid is after all, by its very nature a fantasy incapable of realization. To a theoretical physicist, she is symbolic of many ideas we develop. There are many truths known to fisherman in which one might also find parallels to the goals of scientists: (1) A fish is the only animal that keeps growing after its death; (2) Nothing makes a fish bigger than almost being caught; (3) ''...of all the liars among mankind, the fisherman is the most trustworthy.'' (William Sherwood Fox, in Silken Lines and Silver Hooks); and (4) Men and fish are alike. They both get into trouble when they open their mouths. These quotes may be interpreted as reflecting skepticism regarding the honesty of fisherman, and probably do not reflect adequate admiration for a creative imagination. Is it fair to criticize a person for believing a falsehood that he or she sincerely believes to be true? The fisherman simultaneously invents the lie, and believes in it himself. The parallel with theoretical physics is perhaps only approximate, although we physicists may invent stories that we come to believe, on some rare occasions our ideas actually correspond to a more or less true descriptions of nature. These minor philosophical

  10. Stress concept in transportation of live fishes – a review | Omeji ...

    African Journals Online (AJOL)

    Journal Home > Vol 9, No 2 (2017) > ... This paper review covers work done on various methods of transporting live fishes, factors to consider for fish transportation, the stress concept and how stress can be minimized during fish transportation ...

  11. Energy efficiency : potential fuel savings generated by a national speed limit would be influenced by many other factors.

    Science.gov (United States)

    2008-11-07

    "Congress expressed interest in obtaining information on using a national speed limit to reduce fuel consumption. In response to the request, we reviewed existing literature and consulted knowledgeable stakeholders on the following: (1) What is the r...

  12. Increasing the beta limit due to neoclassical tearing modes by raising the axial safety factor q(0) > 1

    International Nuclear Information System (INIS)

    La Haye, R.J.; Strait, E.J.; Rice, B.W.

    2000-01-01

    Resistive neoclassical tearing modes (NTMs) can cause the stable beta value in long pulse, high confinement plasmas to fall significantly below that predicted by ideal theory. The NTM islands which degrade confinement and limit beta are induced and sustained by helically perturbed bootstrap currents. A combination of shaping and q-profile modification is used in the DIII-D tokamak to increase this beta limit. (author)

  13. Influence of ecological factors and of land use on mercury levels in fish in the Tapajós River basin, Amazon.

    Science.gov (United States)

    Sampaio da Silva, D; Lucotte, M; Paquet, S; Davidson, R

    2009-05-01

    Mercury (Hg) contamination of riparian communities and of environmental compartments of the Amazon can be directly related to the occupation of the territory. The objective of this study was to identify the characteristics of aquatic environments that are associated with high levels of Hg in ichthyofauna. Our research aimed at determining the influence of variables related to fish ecology, types of aquatic environment, fishing activities by local riparian populations, and watershed use on the levels of contamination of ichthyofauna. Six sites were sampled during two distinct periods of the hydrological cycle: at the beginning of descending waters and during low waters. We focused on ten dominant fish species representing four trophic levels: Curimata inornata, Geophagus proximus, Schizodon vittatum, Leporinus fasciatus, Anostomoides laticeps, Hemiodus unimaculatus, Caenotropus labyrinthicus, Hoplias malabaricus, Plagioscion squamosissimus, Acestrorhynchus falcirostris. The study sites, which included lotic and lentic habitats, are exploited year-round by local riparian communities. Spatial variations in Hg contamination in ichthyofauna were determined by factorial analysis of variance taking into account fish diets, seasons, and sampling sites. Multiple regressions were used to check the influence of ecological and anthropogenic variables and variables related to watershed uses, on Hg levels in key species representing the four trophic groups. Each variable was checked independently. Next, multiple regressions were used to verify the concomitant influence of selected variables. Independently of the study site and the phase of the hydrologic cycle, fish Hg contamination followed the trend piscivores>omnivores>herbivores>detritivores. In all the aquatic study sites, Hg levels measured in predatory species were often higher than the 500 ng/g fresh weight threshold. Mean Hg levels in key species were significantly higher during descending waters in lotic environments

  14. Obesity as a risk factor for developing functional limitation among older adults: A conditional inference tree analysis

    Science.gov (United States)

    Objective: To examine the risk factors of developing functional decline and make probabilistic predictions by using a tree-based method that allows higher order polynomials and interactions of the risk factors. Methods: The conditional inference tree analysis, a data mining approach, was used to con...

  15. Study of the cross-reactivity of fish allergens based on a questionnaire and blood testing

    Directory of Open Access Journals (Sweden)

    Yukihiro Kobayashi

    2016-07-01

    Conclusions: Most patients with fish allergies displayed allergic symptoms following the intake of various fish species. In addition, fish parvalbumin and collagen were causative factors of fish allergy and were highly cross-reactive fish panallergens. Therefore, current laws should be revised in Japan and South Korea.

  16. Radium-226 equilibrium between water and lake herring, Coregonus artedii, tissues attained within fish lifetime: confirmation in this species of one assumption in the simple linear concentration factor model

    International Nuclear Information System (INIS)

    Clulow, F.V.; Pyle, G.G.

    1997-01-01

    Equilibrium conditions are assumed in the simple linear concentration factor model commonly used in simulations of contaminant flow through ecosystems and in dose and risk calculations. Predictions derived from a power function model have suggested that if the time scale of the food-chain transfer is less than six years in fish, radium-226 equilibrium will not be achieved in nature, thereby violating the equilibrium requirement in the concentration factor model. Our results indicate 226 Ra equilibrium is achieved in a natural population of lake herring (Coregonus artedii), contrary to predictions of the power function model. (author)

  17. Fishing activities

    Science.gov (United States)

    Oberle, Ferdinand; Puig, Pere; Martin, Jacobo; Micallef, Aaron; Krastel, Sebastian; Savini, Alessandra

    2018-01-01

    Unlike the major anthropogenic changes that terrestrial and coastal habitats underwent during the last centuries such as deforestation, river engineering, agricultural practices or urbanism, those occurring underwater are veiled from our eyes and have continued nearly unnoticed. Only recent advances in remote sensing and deep marine sampling technologies have revealed the extent and magnitude of the anthropogenic impacts to the seafloor. In particular, bottom trawling, a fishing technique consisting of dragging a net and fishing gear over the seafloor to capture bottom-dwelling living resources has gained attention among the scientific community, policy makers and the general public due to its destructive effects on the seabed. Trawling gear produces acute impacts on biota and the physical substratum of the seafloor by disrupting the sediment column structure, overturning boulders, resuspending sediments and imprinting deep scars on muddy bottoms. Also, the repetitive passage of trawling gear over the same areas creates long-lasting, cumulative impacts that modify the cohesiveness and texture of sediments. It can be asserted nowadays that due to its recurrence, mobility and wide geographical extent, industrial trawling has become a major force driving seafloor change and affecting not only its physical integrity on short spatial scales but also imprinting measurable modifications to the geomorphology of entire continental margins.

  18. Characterization of the Cultivable Gut Microflora in Wild-Caught 
Mediterranean Fish Species.

    Science.gov (United States)

    Jammal, Ahmad; Bariche, Michel; Zu Dohna, Heinrich; Kambris, Zakaria

    2017-05-01

    Microflora of the gastrointestinal tract plays important roles in food digestion, nutrient absorption and in host defense against ingested pathogens. Several studies have focused on the microflora of farmed fishes, but the gut flora of wild fishes remains poorly characterized. The aim of this work was to provide an overview of the bacteria colonizing the gut of wild-caught fishes and to determine whether some bacterial species can be pathogenic. We isolated cultivable bacteria from fifteen wild-caught Mediterranean fish species corresponding to different habitat, diet and origin. Bacterial species identity was determined by 16s rRNA gene sequencing for the 61 isolates. The potential pathogenicity of isolated bacteria was investigated using fruit fly (Drosophila melanogaster) and zebrafish (Danio rerio) as model organisms. Two bacterial strains (Serratia sp. and Aeromonas salmonicida) were lethal when microinjected to Drosophila, while zebrafish did not develop any disease when exposed to any of 34 isolated bacterial strains. However, it was interesting to note that two bacterial strains (Shewanella and Arthrobacter) isolated from marine fishes were able to colonize the guts of freshwater zebrafish. The results of this study give an overview of the bacterial species found in the guts of wild fishes living off Beirut seashore. It shows that some parameters believed to be limiting factors to host-gut colonization by bacteria can be overcome by some species. This pilot study could be extended by sampling a larger number of fish species with several specimens per fish species, and by identifying uncultivable bacteria that reside in the fish guts. Our results may have implications for the utilization of certain bacterial species in fish farming or their use as bio-indicators for water and/or food quality.

  19. Fish tapeworm infection

    Science.gov (United States)

    Fish tapeworm infection is an intestinal infection with a parasite found in fish. ... The fish tapeworm ( Diphyllobothrium latum ) is the largest parasite that infects humans. Humans become infected when they eat raw ...

  20. 36 CFR 2.3 - Fishing.

    Science.gov (United States)

    2010-07-01

    ... impact populations of native species adversely, and park management plans do not call for elimination of... time of catching the person did not possess the legal limit of fish. (8) Fishing from motor road bridges, from or within 200 feet of a public raft or float designated for water sports, or within the...

  1. Limited socioeconomic opportunities and Latina teen childbearing: a qualitative study of family and structural factors affecting future expectations.

    Science.gov (United States)

    Minnis, Alexandra M; Marchi, Kristen; Ralph, Lauren; Biggs, M Antonia; Combellick, Sarah; Arons, Abigail; Brindis, Claire D; Braveman, Paula

    2013-04-01

    The decrease in adolescent birth rates in the United States has been slower among Latinas than among other ethnic/racial groups. Limited research has explored how socioeconomic opportunities influence childbearing among Latina adolescents. We conducted in-depth interviews with 65 pregnant foreign- and US-born Latina women (31 adolescents; 34 adults) in two California counties. We assessed perceived socioeconomic opportunities and examined how family, immigration and acculturation affected the relationships between socioeconomic opportunities and adolescent childbearing. Compared with women who delayed childbearing into adulthood, pregnant adolescents described having few resources for educational and career development and experiencing numerous socioeconomic and social barriers to achieving their goals. Socioeconomic instability and policies limiting access to education influenced childbearing for immigrant adolescents. In contrast, family disintegration tied to poverty figured prominently in US-born adolescents' childbearing. Limited socioeconomic opportunities may play a large role in persistently high pregnancy rates among Latina adolescents.

  2. Bull Trout Life History, Genetics, Habitat Needs, and Limiting Factors in Central and Northeast Oregon, Annual Report 2000.

    Energy Technology Data Exchange (ETDEWEB)

    Hemmingsen, Alan R.; Gunckel, Stephanie L.; Sankovich, Paul M.; Howell, Philip J.

    2001-11-01

    This section describes work accomplished in 2000 that continued to address two objectives of this project. These objectives are (1) determine the distribution of juvenile and adult bull trout Salvelinus confluentus and habitats associated with that distribution, and (2) determine fluvial and resident bull trout life history patterns. Completion of these objectives is intended through studies of bull trout in the Grande Ronde, Walla Walla, and John Day basins. These basins were selected because they provide a variety of habitats, from relatively degraded to pristine, and bull trout populations were thought to vary from relatively depressed to robust. In all three basins we continued to monitor the movements of bull trout with radio transmitters applied in 1998 (Hemmingsen, Bellerud, Gunckel and Howell 2001) and 1999 (Hemmingsen, Gunckel and Howell 2001). No new radio transmitters were applied to bull trout of the upper John Day River subbasin, Mill Creek (Walla Walla Basin), or the Grande Ronde Basin in 2000. We did implant radio transmitters in two bull trout incidentally captured in the John Day River near the confluence of the North Fork John Day River. In Mill Creek, we used traps to capture migrant bull trout to obtain data for the third successive year in this stream. With these traps, we intended to determine the timing of bull trout movements both upstream and downstream, and to determine the relative abundance, size and age of migrant fish. Because we captured migrant bull trout with traps for three years in the upper John Day River and its tributaries (Hemmingsen, Bellerud, Buchanan, Gunckel, Shappart and Howell 2001; Hemmingsen, Bellerud, Gunckel and Howell 2001; Hemmingsen, Gunckel and Howell 2001) and traps were no longer needed to capture bull trout for radio-tagging, no traps were operated in the John Day Basin in 2000.

  3. Marine Fish Hybridization

    KAUST Repository

    He, Song

    2017-04-01

    Natural hybridization is reproduction (without artificial influence) between two or more species/populations which are distinguishable from each other by heritable characters. Natural hybridizations among marine fishes were highly underappreciated due to limited research effort; it seems that this phenomenon occurs more often than is commonly recognized. As hybridization plays an important role in biodiversity processes in the marine environment, detecting hybridization events and investigating hybridization is important to understand and protect biodiversity. The first chapter sets the framework for this disseration study. The Cohesion Species Concept was selected as the working definition of a species for this study as it can handle marine fish hybridization events. The concept does not require restrictive species boundaries. A general history and background of natural hybridization in marine fishes is reviewed during in chapter as well. Four marine fish hybridization cases were examed and documented in Chapters 2 to 5. In each case study, at least one diagnostic nuclear marker, screened from among ~14 candidate markers, was found to discriminate the putative hybridizing parent species. To further investigate genetic evidence to support the hybrid status for each hybrid offspring in each case, haploweb analysis on diagnostic markers (nuclear and/or mitochondrial) and the DAPC/PCA analysis on microsatellite data were used. By combining the genetic evidences, morphological traits, and ecological observations together, the potential reasons that triggered each hybridization events and the potential genetic/ecology effects could be discussed. In the last chapter, sequences from 82 pairs of hybridizing parents species (for which COI barcoding sequences were available either on GenBank or in our lab) were collected. By comparing the COI fragment p-distance between each hybridizing parent species, some general questions about marine fish hybridization were discussed: Is

  4. Distribution patterns of fish assemblages in an Eastern Mediterranean intermittent river

    Directory of Open Access Journals (Sweden)

    Vardakas L.

    2015-01-01

    Full Text Available The distribution patterns of fish assemblages within streams can provide insights for river type classifications and may warrant specific conservation actions. However, there is limited knowledge of how fish assemblages assort along a longitudinal axis in Mediterranean intermittent streams. Patterns in spatial and temporal distribution of fish communities were analysed in a Mediterranean intermittent river (Evrotas River located in Southern Greece, hosting three endemic range restricted species of high conservation concern, during the period 2007−2009, with 80% of the river’s total length desiccating in the 2007 and 2008 droughts. The general trend was an increase in fish density and species richness along an upstream-downstream gradient. Fish assemblages from upstream to downstream were characterized by a decrease of the most rheophilic species (Squalius keadicus and an increase of the most stagnophilic species (Tropidophoxinellus spartiaticus. Three river segments, characterized by a high degree of homogeneity were delineated. Habitat and environmental preferences for the studied fish species were identified, with elevation and low flowing habitats being the most important environmental factors affecting fish distribution patterns. The current study provides evidence that even in an intermittent river an assemblage pattern following a longitudinal gradient can be identified, mainly due to the lack of instream barriers that allows recolonization after flow resumption.

  5. Fish welfare: Fish capacity to experience pain

    Directory of Open Access Journals (Sweden)

    Vučinić Marijana

    2009-01-01

    Full Text Available Teleost fish possess similar nociceptive processing systems to those found in terrestrial vertebrates. It means that they react to potential painful stimuli in a similar manner as mammals and birds. However, the welfare of fish has been the focus of less research than that of higher vertebrates. Humans may affect the welfare of fish through fisheries, aquaculture and a number of other activities. There is scientific evidence to support the assumption that fish have the capacity to experience pain because they possess functional nociceptors, endogenous opioids and opioid receptors, brain structures involved in pain processing and pathways leading from nociceptors to higher brain structures. Also, it is well documented that some anaesthetics and analgesics may reduce nociceptive responses in fish. Behavioural indicators in fish such as lip-rubbing and rocking behaviours are the best proof that fish react to potential painful stimuli. This paper is an overview of some scientific evidence on fish capacity to experience pain.

  6. Low skeletal muscle mass is a predictive factor for chemotherapy dose-limiting toxicity in patients with locally advanced head and neck cancer

    NARCIS (Netherlands)

    Wendrich, Anne W; Swartz, Justin E; Bril, Sandra I; Wegner, Inge; de Graeff, Alexander; Smid, Ernst J; de Bree, Remco; Pothen, Ajit J

    OBJECTIVES: Low skeletal muscle mass (SMM) or sarcopenia is emerging as an adverse prognostic factor for chemotherapy dose-limiting toxicity (CLDT) and survival in cancer patients. Our aim was to determine the impact of low SMM on CDLT in patients with locally advanced head and neck squamous cell

  7. Four-loop photon quark form factor and cusp anomalous dimension in the large-N{sub c} limit of QCD

    Energy Technology Data Exchange (ETDEWEB)

    Henn, Johannes [PRISMA Cluster of Excellence, Johannes Gutenberg University, 55099 Mainz (Germany); Lee, Roman N. [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation); Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Smirnov, Alexander V. [Research Computing Center, Moscow State University, 119991 Moscow (Russian Federation); Smirnov, Vladimir A. [Skobeltsyn Institute of Nuclear Physics of Moscow State University, 119991 Moscow (Russian Federation); Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany); Steinhauser, Matthias [Institut für Theoretische Teilchenphysik, Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe (Germany)

    2017-03-27

    We compute the four-loop QCD corrections to the massless quark-anti-quark-photon form factor F{sub q} in the large-N{sub c} limit. From the pole part we extract analytic expressions for the corresponding cusp and collinear anomalous dimensions.

  8. Fish for Feed vs Fish for Food

    OpenAIRE

    Allan, Geoff L.

    2004-01-01

    Aquaculture is the fastest-growing food producing industry sector in the world. Demand for feed ingredients, particularly for preferred protein sources such as fishmeal, fish oil and ‘trash fish’, has also increased, raising questions about sustainability and uses of fish for aquaculture feeds or directly as human food. Approximately 30 million metric tonnes (MMT) of fish from capture fisheries are used each year to produce fishmeal and fish oil. The species used are not usually consumed dire...

  9. Temporally stratified sampling programs for estimation of fish impingement

    International Nuclear Information System (INIS)

    Kumar, K.D.; Griffith, J.S.

    1977-01-01

    Impingement monitoring programs often expend valuable and limited resources and fail to provide a dependable estimate of either total annual impingement or those biological and physicochemical factors affecting impingement. In situations where initial monitoring has identified ''problem'' fish species and the periodicity of their impingement, intensive sampling during periods of high impingement will maximize information obtained. We use data gathered at two nuclear generating facilities in the southeastern United States to discuss techniques of designing such temporally stratified monitoring programs and their benefits and drawbacks. Of the possible temporal patterns in environmental factors within a calendar year, differences among seasons are most influential in the impingement of freshwater fishes in the Southeast. Data on the threadfin shad (Dorosoma petenense) and the role of seasonal temperature changes are utilized as an example to demonstrate ways of most efficiently and accurately estimating impingement of the species

  10. Effects of human population density and proximity to markets on coral reef fishes vulnerable to extinction by fishing.

    Science.gov (United States)

    Brewer, T D; Cinner, J E; Green, A; Pressey, R L

    2013-06-01

    Coral reef fisheries are crucial to the livelihoods of tens of millions of people; yet, widespread habitat degradation and unsustainable fishing are causing severe depletion of stocks of reef fish. Understanding how social and economic factors, such as human population density, access to external markets, and modernization interact with fishing and habitat degradation to affect fish stocks is vital to sustainable management of coral reef fisheries. We used fish survey data, national social and economic data, and path analyses to assess whether these factors explain variation in biomass of coral reef fishes among 25 sites in Solomon Islands. We categorized fishes into 3 groups on the basis of life-history characteristics associated with vulnerability to extinction by fishing (high, medium, and low vulnerability). The biomass of fish with low vulnerability was positively related to habitat condition. The biomass of fishes with high vulnerability was negatively related to fishing conducted with efficient gear. Use of efficient gear, in turn, was strongly and positively related to both population density and market proximity. This result suggests local population pressure and external markets have additive negative effects on vulnerable reef fish. Biomass of the fish of medium vulnerability was not explained by fishing intensity or habitat condition, which suggests these species may be relatively resilient to both habitat degradation and fishing. © 2012 Society for Conservation Biology.

  11. Microbiological spoilage of fish and fish products.

    Science.gov (United States)

    Gram, L; Huss, H H

    1996-11-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative biochemical indicators of spoilage. Shewanella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram-positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish is well understood, much less is known about spoilage of lightly preserved fish products. It is concluded that the spoilage is probably caused by lactic acid bacteria, certain psychotrophic Enterobacteriaceae and/or Photobacterium phosphoreum. However, more work is needed in this area.

  12. Fishing Fish Stem Cells and Nuclear Transplants

    OpenAIRE

    Hong, Yunhan

    2011-01-01

    Fish has been the subject of various research fields, ranging from ecology, evolution, physiology and toxicology to aquaculture. In the past decades fish has attracted considerable attention for functional genomics, cancer biology and developmental genetics, in particular nuclear transfer for understanding of cytoplasmic-nuclear relationship. This special issue reports on recent progress made in fish stem cells and nuclear transfer.

  13. Predictive modeling of deep-sea fish distribution in the Azores

    Science.gov (United States)

    Parra, Hugo E.; Pham, Christopher K.; Menezes, Gui M.; Rosa, Alexandra; Tempera, Fernando; Morato, Telmo

    2017-11-01

    Understanding the link between fish and their habitat is essential for an ecosystem approach to fisheries management. However, determining such relationship is challenging, especially for deep-sea species. In this study, we applied generalized additive models (GAMs) to relate presence-absence and relative abundance data of eight economically-important fish species to environmental variables (depth, slope, aspect, substrate type, bottom temperature, salinity and oxygen saturation). We combined 13 years of catch data collected from systematic longline surveys performed across the region. Overall, presence-absence GAMs performed better than abundance models and predictions made for the observed data successfully predicted the occurrence of the eight deep-sea fish species. Depth was the most influential predictor of all fish species occurrence and abundance distributions, whereas other factors were found to be significant for some species but did not show such a clear influence. Our results predicted that despite the extensive Azores EEZ, the habitats available for the studied deep-sea fish species are highly limited and patchy, restricted to seamounts slopes and summits, offshore banks and island slopes. Despite some identified limitations, our GAMs provide an improved knowledge of the spatial distribution of these commercially important fish species in the region.

  14. Contamination with heavy metals and bacteria in some local and imported fish and fish products

    International Nuclear Information System (INIS)

    Salem, S.B.; El-Dashlout, A.A.; El-Schiwee, M.A.; EL-Shourbagy, G.A.; Ibrahim, R.E.

    2004-01-01

    Some local and imported fish and fish products sold in retail markets of three cities at Sharkia Governorate, Egypt, were examined against heavy metals contamination (i.e. Pb, Cd and Hg) and the presence of some specific groups of bacteria. The results showed that concentrations of Pb in fresh and frozen fish, salted and smoked fish and canned fish samples were lower than the permissible limits recommended by the Egyptian Organization 1993 (1.0 mg/kg). On the other hand, all the tested fish and fish products of collected samples showed levels of Cd (0.29-0.41 mg/kg) higher than the permissible limit (0.10 mg/kg) recommended by the Egyptian Organization. Such limits should be re-considered because the limit determined by WHO (1992) was 0.5 mg/kg. Mercury level in fresh mullet was equal or lower (0.46-0.50 mg/kg) than the limit of Egyptian Organization (0.50 mg/kg) while other fresh and frozen fish, salted and smoked fish samples had higher Hg than the allowance. In most cases, imported canned products of sardine, mackerel and tuna had higher Pb, Cd and Hg concentrations than that found in the local ones. Among fresh fish samples, such as mackarona, contained the highest total bacterial count, while mullet was the lowest. Considering salted and smoked fish, heavy salted mullet had the highest total bacterial count, while the lowest number was recorded in salted sardine. Smoked herring showed lowest total bacterial count than salted samples. Generally, no correlation was observed between fish species or consumption place and the contamination with heavy metals and bacteria

  15. Dynamite fishing in Tanzania.

    Science.gov (United States)

    Slade, Lorna M; Kalangahe, Baraka

    2015-12-30

    Fishing using explosives is common in Tanzanian waters; it is considered to be more widely practised now than at any other point in history. Mwambao Coastal Community Network, a Tanzanian NGO carried out a multi-stakeholder consultation in April 2014 initiated through the concern of private investors and tourism operators. Consultations were held with villagers, fisheries officers, government officers, hoteliers, dive operators, fish processors, NGOs and other key individuals, and shed some light on key factors enabling this practice to flourish. Key areas identified for attention include engendering political will at all levels, upholding of the law through a non-corrupt enforcement and judicial system, and defining clear roles and responsibilities for monitoring and surveillance. The work identified other successful initiatives which have tackled this pervasive practice including projects that build local capacity for marine governance, villages that have declared themselves intolerant of blast-fishing, and private-public partnerships for patrol and protection. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Exploring the interaction of activity limitations with context, systems, community and personal factors in accessing public health care services: A presentation of South African case studies.

    Science.gov (United States)

    Mji, Gubela; Braathen, Stine H; Vergunst, Richard; Scheffler, Elsje; Kritzinger, Janis; Mannan, Hasheem; Schneider, Marguerite; Swartz, Leslie; Visagie, Surona

    2017-02-08

    There are many factors that influence access to public health services, such as the context people live in, the existing health services, and personal, cultural and community factors. People with disabilities (activity limitations), through their experience of health services, may offer a particular understanding of the performance of the health services, thus exposing health system limitations more clearly than perhaps any other health service user. This article explores how activity limitations interact with factors related to context, systems, community and personal factors in accessing public health care services in South Africa. We present four case studies of people with disabilities from four low-resource diverse contexts in South Africa (rural, semi-rural, farming community and peri-urban) to highlight challenges of access to health services experienced by people with activity limitations in a variety of contexts. One case study of a person with disabilities was chosen from each study setting to build evidence using an intensive qualitative case study methodology to elucidate individual and household experiences of challenges experienced by people with activity limitations when attempting to access public health services. In-depth interviews were used to collect data, using an interview guide. The analysis was conducted in the form of a thematic analysis using the interview topics as a starting point. First, these four case studies demonstrate that equitable access to health services for people with activity limitations is influenced by a complex interplay of a variety of factors for a single individual in a particular context. Secondly, that while problems with access to public health services are experienced by everyone, people with activity limitations are affected in particular ways making them particularly vulnerable in using public health services. The revitalisation of primary health care and the introduction of national health

  17. In silico evaluation of limited blood sampling strategies for individualized recombinant factor IX prophylaxis in hemophilia B patients

    NARCIS (Netherlands)

    Preijers, T.; Hazendonk, H. C. A. M.; Fijnvandraat, K.; Leebeek, F. W. G.; Cnossen, M. H.; Mathôt, R. A. A.

    2017-01-01

    Background Patients with severe hemophilia B regularly administer prophylactic intravenous doses of clotting factor IX concentrate to maintain a trough level of at least 0.01 IU mL(-1) in order to prevent joint bleeds. Assessment of individual pharmacokinetic (PK) parameters allows individualization

  18. Diapause induction as an interplay between seasonal token stimuli, and modifying and directly limiting factors: hibernation in Chymomyza costata

    Czech Academy of Sciences Publication Activity Database

    Košťál, Vladimír; Mollaei, M.; Schöttner, Konrad

    2016-01-01

    Roč. 41, č. 4 (2016), s. 344-357 ISSN 0307-6962 R&D Projects: GA ČR GA13-01057S Institutional support: RVO:60077344 Keywords : environmental signals * overcrowding * photoperiodism Subject RIV: ED - Physiology Impact factor: 1.364, year: 2016 http://onlinelibrary.wiley.com/doi/10.1111/phen.12159/abstract

  19. Limited human epidermal growth factor receptor 2 discordance in metastatic breast cancer patients treated with trastuzumab, a population based study

    NARCIS (Netherlands)

    van Rooijen, J.M.; de Munck, L.; de Graaf, J.C.; Siesling, Sabine; de Vries, Erik G.; Boers, J.E.

    2014-01-01

    Background Accurate assessment of the human epidermal growth factor receptor 2 (HER2) in breast cancer is essential for proper treatment decisions. HER2 positivity confirmation rates in breast cancer trials by central testing pathology laboratories were reported to be approximately 85%. The aim of

  20. Limited human epidermal growth factor receptor 2 discordance in metastatic breast cancer patients treated with trastuzumab, a population based study

    NARCIS (Netherlands)

    van Rooijen, J. M.; de Munck, L.; de Graaf, J. C.; Siesling, S.; de Vries, E. G.; Boers, J. E.

    Background: Accurate assessment of the human epidermal growth factor receptor 2 (HER2) in breast cancer is essential for proper treatment decisions. HER2 positivity confirmation rates in breast cancer trials by central testing pathology laboratories were reported to be approximately 85%. The aim of

  1. Relations between altered stramflow variability and fish assemblages in Eastern USA streams

    Science.gov (United States)

    Meador, Michael R.; Carlisle, Daren M.

    2012-01-01

    Although altered streamflow has been implicated as a major factor affecting fish assemblages, understanding the extent of streamflow alteration has required quantifying attributes of the natural flow regime. We used predictive models to quantify deviation from expected natural streamflow variability for streams in the eastern USA. Sites with >25% change in mean daily streamflow variability compared with what would be expected in a minimally disturbed environment were defined as having altered streamflow variability, based on the 10th and 90th percentiles of the distribution of streamflow variability at 1279 hydrological reference sites. We also used predictive models to assess fish assemblage condition and native species loss based on the proportion of expected native fish species that were observed. Of the 97 sites, 49 (50.5%) were classified as altered with reduced streamflow variability, whereas no sites had increased streamflow variability. Reduced streamflow variability was related to a 35% loss in native fish species, on average, and a >50% loss of species with a preference for riffle habitats. Conditional probability analysis indicated that the probability of fish assemblage impairment increased as the severity of altered streamflow variability increased. Reservoir storage capacity and wastewater discharges were important predictors of reduced streamflow variability as revealed by random forest analysis. Management and conservation of streams will require careful consideration of natural streamflow variation and potential factors contributing to altered streamflow within the entire watershed to limit the loss of critical stream habitats and fish species uniquely adapted to live in those habitats.

  2. Prevalence and risk factors for allergic rhinitis in two resource-limited settings in Peru with disparate degrees of urbanization.

    Science.gov (United States)

    Baumann, L M; Romero, K M; Robinson, C L; Hansel, N N; Gilman, R H; Hamilton, R G; Lima, J J; Wise, R A; Checkley, W

    2015-01-01

    Allergic rhinitis is a disease with a high global disease burden, but risk factors that contribute to this condition are not well understood. To assess the prevalence and risk factors of allergic rhinitis in two Peruvian populations with disparate degrees of urbanization. We conducted a population-based, cross-sectional study on 1441 children aged 13-15 years at enrollment (mean age 14.9 years, 51% boys) to investigate the prevalence of allergic disease. We used a standardized, Spanish validated questionnaire to determine the prevalence of allergic rhinitis and asked about sociodemographics and family history of allergies. Children also underwent spirometry, exhaled nitric oxide, allergy skin testing to 10 common household allergens and provided a blood sample for measurement of 25OH vitamin D and total serum IgE. Overall prevalence of allergic rhinitis was 18% (95% CI 16% to 20%). When stratified by site, the prevalence of allergic rhinitis was 23% Lima vs. 13% in Tumbes (P overweight (1.5, 1.0-2.3); exhaled nitric oxide ≥ 20 ppb (1.9, 1.3-2.7); and total serum IgE ≥ 95th percentile (2.4, 1.2-4.8). Population attributable risk of important factors for allergic rhinitis were 25% for high exhaled nitric oxide, 22% for allergic sensitization to common household aeroallergens, 22% for paternal rhinitis, 10% for being overweight and 7% for an elevated total serum IgE. Allergic rhinitis was prevalent in both settings, and important risk factors include elevated exhaled nitric oxide, allergic sensitization to common household aeroallergens, parental rhinitis, being overweight and high total serum IgE. When considering subject-specific factors, the difference in prevalence between the urban and rural settings became non-important. © 2014 John Wiley & Sons Ltd.

  3. Effects of Pollution on Freshwater Fish.

    Science.gov (United States)

    Brungs, W. A.; And Others

    1978-01-01

    Presents a literature review of the effects of pollution on freshwater fish, covering publications of 1976-77. This review includes: (1) water quality; (2) pesticide pollutants; (3) chemical pollutants; (4) miscellaneous pollutants; and (5) physical factors of pollution on freshwater fish. A list of 338 references is also presented. (HM)

  4. Establishing a public health analytical service based on chemical methods for detecting and quantifying Pacific ciguatoxin in fish samples.

    Science.gov (United States)

    Stewart, Ian; Eaglesham, Geoffrey K; Poole, Sue; Graham, Glenn; Paulo, Carl; Wickramasinghe, Wasantha; Sadler, Ross; Shaw, Glen R

    2010-10-01

    A referee analysis method for the detection and quantification of Pacific ciguatoxins in fish flesh has recently been established by the public health analytical laboratory for the State of Queensland, Australia. Fifty-six fish samples were analysed, which included 10 fillets purchased as negative controls. P-CTX-1 was identified in 27 samples, and P-CTX-2 and P-CTX-3 were found in 26 of those samples. The range of P-CTX-1 concentrations was 0.04-11.4 microg/kg fish flesh; coefficient of variation from 90 replicate analyses was 7.4%. A liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) method utilising a rapid methanol extraction and clean-up is reliable and reproducible, with the detection limit at 0.03 microg/kg fish flesh. Some matrix effects are evident, with fish oil content a likely signal suppression factor. Species identification of samples by DNA sequence analysis revealed some evidence of fish substitution or inadvertent misidentification, which may have implications for the management and prevention of ciguatera poisoning. Blinded inspection of case notes from suspect ciguatera poisoning cases showed that reporting of ciguatera-related paraesthesias was highly predictable for the presence of ciguatoxins in analysed fish, with 13 of 14 expected cases having consumed fish that contained P-CTX-1 (p<0.001, Fishers Exact Test). Crown Copyright 2009. Published by Elsevier Ltd. All rights reserved.

  5. Fishing destabilizes the biomass flow in the marine size spectrum.

    Science.gov (United States)

    Rochet, M-J; Benoît, E

    2012-01-22

    Fishing impacts on marine food webs are predicted by simulations of a size spectrum community model. In this model, predation is determined by predator and prey size and abundance, and drives predator growth and prey mortality. Fishing amplifies temporal oscillations in the biomass flow. Oscillations appear at lower fishing intensity and have wider amplitude when fishing is selective (removes a narrow size range) and/or when large fish are targeted, than when fishing is more balanced (catching a larger size range) or when small fish are targeted. A novel index of size diversity is developed, and is shown to be sensitive to both fishing intensity and selectivity. To avoid unstable food web dynamics with potential harmful consequences for fisheries, limiting both fishing intensity and selectivity might be an appropriate exploitation strategy.

  6. Fish allergens at a glance: Variable allergenicity of parvalbumins, the major fish allergens

    OpenAIRE

    Annette eKuehn; Ines eSwoboda; Karthik eArumugam; Christiane eHilger; François eHentges; François eHentges

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand,...

  7. Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens

    OpenAIRE

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand,...

  8. Fish Farmers' Perception of Climate change impact on fish ...

    African Journals Online (AJOL)

    Michael Madukwe

    *Department of Agricultural Extension and Management ... Respondents in the area perceived climate change factors ... rural farmers who implement their regular annual farm business plans risk total ... 2010). Constraints to increased fish production in Nigeria include, among others, ..... Build ponds close to water sources.

  9. Fish under exercise

    NARCIS (Netherlands)

    Palstra, A.P.; Planas, J.V.

    2011-01-01

    Improved knowledge on the swimming physiology of fish and its application to fisheries science and aquaculture (i.e., farming a fitter fish) is currently needed in the face of global environmental changes, high fishing pressures, increased aquaculture production as well as increased concern on fish

  10. Meaningful learning: The essential factor for conceptual change in limited or inappropriate propositional hierarchies leading to empowerment of learners

    Science.gov (United States)

    Novak, Joseph D.

    2002-07-01

    The construction and reconstruction of meanings by learners requires that they actively seek to integrate new knowledge with knowledge already in their cognitive structure. Ausubel's assimilation theory of cognitive learning has been shown to be effective in guiding research and instructional design to facilitate meaningful learning (Ausubel, The psychology of meaningful verbal learning, New York: Grune and Stratton, 1963; Educational psychology: A cognitive view, New York: Holt, Rinehart and Winston, 1968; The acquisition and retention of knowledge, Dordrecht: Kluwer, 2000). Gowin's Vee heuristic has been employed effectively to aid teachers and students in understanding the constructed nature of knowledge (Gowin, Educating, Ithaca, NY: Cornell University Press, 1981). Situated learning occurs when learning is by rote or at a lower level of meaningful learning. Concept mapping has been used effectively to aid meaningful learning with resulting modification of student's knowledge structures. When these knowledge structures are limited or faulty in some way, they may be referred to as Limited or Inappropriate Propositional Hierarchies (LIPH's). Conceptual change, or more accurately conceptual reconstrution, requires meaningful learning to modify LIPH's. Collaborative group learning facilitates meaningful learning and new knowledge construction. World-wide economic changes are forcing major changes in business and industry placing a premium on the power and value of knowledge and new knowledge production. These changes require changes in school and university education that centers on the nature and power of meaningful learning. New computer tools are available to facilitate teaching activities targeted at modifying LIPH's, and aiding meaningful learning in general.

  11. Dam crossing by migrating fish. State of the technique

    International Nuclear Information System (INIS)

    Travade, F.; Larinier, M.

    1992-01-01

    In the first part of this paper, the present state of design of fish ways is reviewed, focusing on the interest and the limits of each type of fish facility. The second part deals with downstream migration problems at hydroelectric power plants: fish damage in spillways and hydraulic turbines and design of fish screening and other diversionary techniques used to prevent entry of downstream migrant into intakes. 14 refs., 13 figs

  12. Meet the surrogate fish

    International Nuclear Information System (INIS)

    Johnson, Bob; Neitzel, Duane; Moxon, Suzanne

    1999-01-01

    This article gives details of the US Department of Energy's innovative research into the development of a sensor system that will work as a surrogate fish to provide information to aid the design of fish-friendly turbines for hydroelectric power plants. The selection of the dams for the testing of sensor fish, the release and recovery of the sensor fish, the recording of the physical forces exerted on fish as they pass through the turbines, and use of the information gathered to build more sensor fish are discussed. Fish investigations conducted at the Pacific Northwest National Laboratory are briefly described. (UK)

  13. Plastic fish

    CERN Multimedia

    Antonella Del Rosso

    2015-01-01

    In terms of weight, the plastic pollution in the world’s oceans is estimated to be around 300,000 tonnes. This plastic comes from both land-based and ocean-based sources. A lecture at CERN by chemist Wolfgang Trettnak addressed this issue and highlighted the role of art in raising people’s awareness.   Artwork by Wolfgang Trettnak. Packaging materials, consumer goods (shoes, kids’ toys, etc.), leftovers from fishing and aquaculture activities… our oceans and beaches are full of plastic litter. Most of the debris from beaches is plastic bottles. “PET bottles have high durability and stability,” explains Wolfgang Trettnak, a chemist by education and artist from Austria, who gave a lecture on this topic organised by the Staff Association at CERN on 26 May. “PET degrades very slowly and the estimated lifetime of a bottle is 450 years.” In addition to the beach litter accumulated from human use, rivers bring several ki...

  14. Three Kinds of Fish

    DEFF Research Database (Denmark)

    Høst, Jeppe Engset

    2012-01-01

    There are three kinds of fish. Fish you were given, fish you bought and fish you lease. This might sound a bit odd, but it is nevertheless the basis for the activities of Danish commercial fishers since the introduction of transferable fishing concessions (TFCs) in 2007. In the current 2012 reform...... of market based systems are wild speculation, concentration and monopolization of fishing access and subsequent leasing with fishing communities and new entrants very likely being worse off (see for example the chapter “From fishing rights to financial derivatives” is this volume or Olson 2011; Sumaila 2010...... will examine five Danish fishing operations and discuss how they have reacted in different ways to the newly introduced system of transferable fishing concessions. By introducing TFCs as a solution to fleet overcapacity, the EU Commission will also be introducing a system where buying, selling and leasing...

  15. PhoB activates Escherichia coli O157:H7 virulence factors in response to inorganic phosphate limitation.

    Directory of Open Access Journals (Sweden)

    Samuel Mohammed Chekabab

    Full Text Available Enterohemorrhagic Escherichia coli (EHEC, an emerging food- and water-borne hazard, is highly pathogenic to humans. In the environment, EHEC must survive phosphate (Pi limitation. The response to such Pi starvation is an induction of the Pho regulon including the Pst system that senses Pi variation. The interplay between the virulence of EHEC, Pho-Pst system and environmental Pi remains unknown. To understand the effects of Pi deprivation on the molecular mechanisms involved in EHEC survival and virulence under Pho regulon control, we undertook transcriptome profiling of the EDL933 wild-type strain grown under high Pi and low Pi conditions and its isogenic ΔphoB mutant grown in low Pi conditions. The differentially expressed genes included 1067 Pi-dependent genes and 603 PhoB-dependent genes. Of these 131 genes were both Pi and PhoB-dependent. Differentially expressed genes that were selected included those involved in Pi homeostasis, cellular metabolism, acid stress, oxidative stress and RpoS-dependent stress responses. Differentially expressed virulence systems included the locus of enterocyte effacement (LEE encoding the type-3 secretion system (T3SS and its effectors, as well as BP-933W prophage encoded Shiga toxin 2 genes. Moreover, PhoB directly regulated LEE and stx2 gene expression through binding to specific Pho boxes. However, in Pi-rich medium, constitutive activation of the Pho regulon decreased LEE gene expression and reduced adherence to HeLa cells. Together, these findings reveal that EHEC has evolved a sophisticated response to Pi limitation involving multiple biochemical strategies that contribute to its ability to respond to variations in environmental Pi and to coordinating the virulence response.

  16. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2016-01-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish.

  17. The pre-rRNA processing factor DEF is rate limiting for the pathogenesis of MYCN-driven neuroblastoma.

    Science.gov (United States)

    Tao, T; Sondalle, S B; Shi, H; Zhu, S; Perez-Atayde, A R; Peng, J; Baserga, S J; Look, A T

    2017-07-06

    The nucleolar factor, digestive organ expansion factor (DEF), has a key role in ribosome biogenesis, functioning in pre-ribosomal RNA (pre-rRNA) processing as a component of the small ribosomal subunit (SSU) processome. Here we show that the peripheral sympathetic nervous system (PSNS) is very underdeveloped in def-deficient zebrafish, and that def haploinsufficiency significantly decreases disease penetrance and tumor growth rate in a MYCN-driven transgenic zebrafish model of neuroblastoma that arises in the PSNS. Consistent with these findings, DEF is highly expressed in human neuroblastoma, and its depletion in human neuroblastoma cell lines induces apoptosis. Interestingly, overexpression of MYCN in zebrafish and in human neuroblastoma cells results in the appearance of intermediate pre-rRNAs species that reflect the processing of pre-rRNAs through Pathway 2, a pathway that processes pre-rRNAs in a different temporal order than the more often used Pathway 1. Our results indicate that DEF and possibly other components of the SSU processome provide a novel site of vulnerability in neuroblastoma cells that could be exploited for targeted therapy.

  18. Investigation of biological condition of fish species in lower Ogun ...

    African Journals Online (AJOL)

    The study was carried out to investigate the biological condition of fish species in lower Ogun River wetlands. A total of 175 individual fish belonging to 10 species were collected from artisanal fishermen using different types of fishing gears. Two biological indices; condition factor “K” and growth exponent “b” obtained from ...

  19. Plant size and abiotic factors determine the intra-specific variation in the multi-stemmed architecture of Prunus lusitanica in the Northeast limit of its global distribution

    Directory of Open Access Journals (Sweden)

    A. Muñoz Costa

    2013-12-01

    Full Text Available Aim of study: The present work provides novel insights on factors (either intrinsic or extrinsic that trigger sprouting in woody species living at range margins. We aim to explain the inter-individual variability in the multi-stemmed architecture of Prunus lusitanica L., an Iberian evergreen relict tree related to the Tertiary flora.Area of study: Northeastern Mediterranean mountains of the Iberian Peninsula, the Northeast limit of the global distribution of the species.Material and Methods: We gathered data on two modes of vegetative reproduction, basal and layering sprouts, in 288 clumps of Prunus lusitanica from four populations. We modeled and analyzed the effect of environmental factors (topography, canopy cover, soil moisture and disturbances and plant size (diameter at breast height on sprouting by means of Generalized Linear Model and other statistical approaches.Main results: Plant size arises as the principal factor to explain the variability of the numbers of both types of sprouts yet it is not a trigger factor. Natural and anthropogenic disturbances promote basal and layering shoots, while tree canopy is mainly relevant for basal shoots, and slope and soil moisture are significant factors for layering shoots.Research highlights: The multi-stemmed architecture of P. lusitanica at the Northeastern limit of its worldwide distribution is triggered by local environmental factors and disturbances. Each external factor shows different levels of influence on the variability and type of vegetative reproduction yet the intensity of the response is driven by the size of the largest trunk of each clump.Key words: vegetative reproduction; sprouting; disturbances; woody plants; relict tree; subtropical; Iberian Peninsula.

  20. Linking hydrologic, physical and chemical habitat environments for the potential assessment of fish community rehabilitation in a developing city

    Science.gov (United States)

    Zhao, C. S.; Yang, S. T.; Liu, C. M.; Dou, T. W.; Yang, Z. L.; Yang, Z. Y.; Liu, X. L.; Xiang, H.; Nie, S. Y.; Zhang, J. L.; Mitrovic, S. M.; Yu, Q.; Lim, R. P.

    2015-04-01

    Aquatic ecological rehabilitation is increasingly attracting considerable public and research attention. An effective method that requires less data and expertise would help in the assessment of rehabilitation potential and in the monitoring of rehabilitation activities as complicated theories and excessive data requirements on assemblage information make many current assessment models expensive and limit their wide use. This paper presents an assessment model for restoration potential which successfully links hydrologic, physical and chemical habitat factors to fish assemblage attributes drawn from monitoring datasets on hydrology, water quality and fish assemblages at a total of 144 sites, where 5084 fish were sampled and tested. In this model three newly developed sub-models, integrated habitat index (IHSI), integrated ecological niche breadth (INB) and integrated ecological niche overlap (INO), are established to study spatial heterogeneity of the restoration potential of fish assemblages based on gradient methods of habitat suitability index and ecological niche models. To reduce uncertainties in the model, as many fish species as possible, including important native fish, were selected as dominant species with monitoring occurring over several seasons to comprehensively select key habitat factors. Furthermore, a detrended correspondence analysis (DCA) was employed prior to a canonical correspondence analysis (CCA) of the data to avoid the "arc effect" in the selection of key habitat factors. Application of the model to data collected at Jinan City, China proved effective reveals that three lower potential regions that should be targeted in future aquatic ecosystem rehabilitation programs. They were well validated by the distribution of two habitat parameters: river width and transparency. River width positively influenced and transparency negatively influenced fish assemblages. The model can be applied for monitoring the effects of fish assemblage restoration

  1. Textiles: Some technocal information and data II: Conversion factors, fibre properties, spinning limits, typical twist factors, weaving performannce and transfer printing temperatures.

    CSIR Research Space (South Africa)

    Hunter, L

    1978-07-01

    Full Text Available OF THE CSIR P.O. B O X 1 1 2 4 P O R T E L I Z A B E T H R E P U B L I C O F S O U T H A F R I C A WOL 47 ISBN 0 7988 1360 1 Contents INTRODUCTION ........................................................... Page .; ... 1 CONVERSION FACTORSAND... ........................................................................................ 118 REFERENCES TEXTILES: SOME TECHNICAL INFORMATION AND DATA 11: CONVERSION FACTORS, FIBRE PROPERTIES, SPINNING L I M I T S , T Y P I C A L T W I S T F A C T O R S , W E A V I N G PERFORMANCE A N D TRANSFER PRINTING TEMPERATURES 6.5, L...

  2. Amino acids supply in culture media is not a limiting factor in the matrix synthesis of engineered cartilage tissue

    Science.gov (United States)

    Ng, K. W.; DeFrancis, J. G.; Kugler, L. E.; Kelly, T.-A. N.; Ho, M. M.; O’Conor, C. J.; Ateshian, G. A.; Hung, C. T.

    2013-01-01

    Summary Increased amino acid supplementation (0.5×, 1.0×, and 5.0× recommended concentrations or additional proline) was hypothesized to increase the collagen content in engineered cartilage. No significant differences were found between groups in matrix content or dynamic modulus. Control constructs possessed the highest compressive Young’s modulus on day 42. On day 42, compared to controls, decreased type II collagen was found with 0.5×, 1.0×, and 5.0× supplementation and significantly increased DNA content found in 1.0× and 5.0×. No effects were observed on these measures with added proline. These results lead us to reject our hypothesis and indicate that the low collagen synthesis in engineered cartilage is not due to a limited supply of amino acids in media but may require a further stimulatory signal. The results of this study also highlight the impact that culture environment can play on the development of engineered cartilage. PMID:17713744

  3. An Investigation of Influencing Factors on Practical Sub-Diffraction-Limit Focusing of Planar Super-Oscillation Lenses

    Directory of Open Access Journals (Sweden)

    Yiting Yu

    2018-03-01

    Full Text Available Planar super-oscillation lenses (SOLs can fulfill super-resolution focusing and nanoscopic imaging in the far field without the contribution of evanescent waves. Nevertheless, the existing deviations between the design and experimental results have been seldomly investigated, leaving the practical applications of SOLs unpredictable and uncontrollable. In this paper, some application-oriented issues are taken into consideration, such as the inevitable fabrication errors and the size effect of the designed SOLs, with the aim of providing an engineering reference to elaborately customize the demanded focusing light field. It turned out that a thicker structural film makes the focal spots enlarged, while the sloped sidewalls just weaken the intensity of the focal hotspot. Furthermore, the focal lengths are diminished with the decrease of device size, while the focal spots are enlarged. This research will promote the wide-spread applications of SOLs for sub-diffraction-limit far-field focusing in the areas of nanoscopy and high-density optical storage.

  4. KANSL1 variation is not a major contributing factor in self-limited focal epilepsy syndromes of childhood.

    Directory of Open Access Journals (Sweden)

    Kenneth A Myers

    Full Text Available KANSL1 haploinsufficiency causes Koolen-de Vries syndrome (KdVS, characterized by dysmorphic features and intellectual disability; amiable personality, congenital malformations and seizures also commonly occur. The epilepsy phenotypic spectrum in KdVS is broad, but most individuals have focal seizures with some having a phenotype resembling the self-limited focal epilepsies of childhood (SFEC. We hypothesized that variants in KANSL1 contribute to pathogenesis of SFEC.We screened KANSL1 for single nucleotide variants in 90 patients with SFEC. We then screened a cohort of 208 patients with two specific SFEC syndromes, childhood epilepsy with centrotemporal spikes (CECTS and atypical childhood epilepsy with centrotemporal spikes (ACECTS for KANSL1 variants. The second cohort was also used to evaluate minor allelic variants that appeared overrepresented in the initial cohort.One variant, p.Lys104Thr, was predicted damaging and appeared overrepresented in our 90-patient cohort compared to Genome Aggregation Database (gnomAD allele frequency (0.217 to 0.116, with no homozygotes in gnomAD. However, there was no difference in p.Lys104Thr allele frequency in the follow-up CECTS/ACECTS cohort and controls. Four rare KANSL1 variants of uncertain significance were identified in the CECTS/ACECTS cohort.Our data do not support a major role for KANSL1 variants in pathogenesis of SFEC.

  5. Scaling of graphene field-effect transistors supported on hexagonal boron nitride: radio-frequency stability as a limiting factor

    Science.gov (United States)

    Feijoo, Pedro C.; Pasadas, Francisco; Iglesias, José M.; Martín, María J.; Rengel, Raúl; Li, Changfeng; Kim, Wonjae; Riikonen, Juha; Lipsanen, Harri; Jiménez, David

    2017-12-01

    The quality of graphene in nanodevices has increased hugely thanks to the use of hexagonal boron nitride as a supporting layer. This paper studies to which extent hBN together with channel length scaling can be exploited in graphene field-effect transistors (GFETs) to get a competitive radio-frequency (RF) performance. Carrier mobility and saturation velocity were obtained from an ensemble Monte Carlo simulator that accounted for the relevant scattering mechanisms (intrinsic phonons, scattering with impurities and defects, etc). This information is fed into a self-consistent simulator, which solves the drift-diffusion equation coupled with the two-dimensional Poisson’s equation to take full account of short channel effects. Simulated GFET characteristics were benchmarked against experimental data from our fabricated devices. Our simulations show that scalability is supposed to bring to RF performance an improvement that is, however, highly limited by instability. Despite the possibility of a lower performance, a careful choice of the bias point can avoid instability. Nevertheless, maximum oscillation frequencies are still achievable in the THz region for channel lengths of a few hundreds of nanometers.

  6. Mercury and stable isotope signatures in caged marine fish and fish feeds

    Energy Technology Data Exchange (ETDEWEB)

    Onsanit, Sarayut; Chen, Min; Ke, Caihuan [State Key Laboratory for Marine Environmental Science, College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005 (China); Wang, Wen-Xiong [State Key Laboratory for Marine Environmental Science, College of Oceanography and Environmental Science, Xiamen University, Xiamen 361005 (China)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer Mercury concentrations in caged fish were closely related to Hg concentrations in fish feeds. Black-Right-Pointing-Pointer The trophic transfer factor of methylmercury was dependent on fish feeds, and was the highest for fish fed on pellet feeds. Black-Right-Pointing-Pointer Fish farming may be a good way of reducing the human exposure to Hg because Hg levels can be carefully controlled. - Abstract: Total mercury (THg) and methylmercury (MeHg) concentrations were determined in four species of marine caged carnivorous fish, one species of herbivorous fish and three types of fish feeds (dried pellet feed, forage fish and fish viscera), collected from five cage sites in the rural areas along Fujian coastline, China. For the carnivorous fish, the concentrations of THg and MeHg ranged from 0.03 to 0.31 {mu}g/g and from 0.02 to 0.30 {mu}g/g on wet weight basis, respectively. The concentrations were lower for the herbivorous fish with both within the range of 0.01-0.03 {mu}g/g. Out of the three tested fish feeds, tuna viscera contained the highest level of mercury (0.20 {mu}g/g THg and 0.13 {mu}g/g MeHg), with pellet feed containing the lowest level (0.05 {mu}g/g THg and 0.01 {mu}g/g MeHg). The calculated trophic transfer factor of MeHg was the highest (12-64) for fish fed on pellet feeds, and was the lowest for fish fed on tuna viscera. A significant relationship was found between Hg concentrations in caged fish and in fish feeds, thus Hg was primarily accumulated from the diet. Furthermore, the stable isotope {delta}{sup 15}N was positively correlated with the Hg concentration in two caged sites, indicating that {delta}{sup 15}N may be a suitable tool for tracking mercury in caged fish. We conclude that fish farming may be a good way of reducing the human exposure to Hg because mercury levels can be carefully controlled in such farming systems.

  7. Mercury and stable isotope signatures in caged marine fish and fish feeds

    International Nuclear Information System (INIS)

    Onsanit, Sarayut; Chen, Min; Ke, Caihuan; Wang, Wen-Xiong

    2012-01-01

    Highlights: ► Mercury concentrations in caged fish were closely related to Hg concentrations in fish feeds. ► The trophic transfer factor of methylmercury was dependent on fish feeds, and was the highest for fish fed on pellet feeds. ► Fish farming may be a good way of reducing the human exposure to Hg because Hg levels can be carefully controlled. - Abstract: Total mercury (THg) and methylmercury (MeHg) concentrations were determined in four species of marine caged carnivorous fish, one species of herbivorous fish and three types of fish feeds (dried pellet feed, forage fish and fish viscera), collected from five cage sites in the rural areas along Fujian coastline, China. For the carnivorous fish, the concentrations of THg and MeHg ranged from 0.03 to 0.31 μg/g and from 0.02 to 0.30 μg/g on wet weight basis, respectively. The concentrations were lower for the herbivorous fish with both within the range of 0.01–0.03 μg/g. Out of the three tested fish feeds, tuna viscera contained the highest level of mercury (0.20 μg/g THg and 0.13 μg/g MeHg), with pellet feed containing the lowest level (0.05 μg/g THg and 0.01 μg/g MeHg). The calculated trophic transfer factor of MeHg was the highest (12–64) for fish fed on pellet feeds, and was the lowest for fish fed on tuna viscera. A significant relationship was found between Hg concentrations in caged fish and in fish feeds, thus Hg was primarily accumulated from the diet. Furthermore, the stable isotope δ 15 N was positively correlated with the Hg concentration in two caged sites, indicating that δ 15 N may be a suitable tool for tracking mercury in caged fish. We conclude that fish farming may be a good way of reducing the human exposure to Hg because mercury levels can be carefully controlled in such farming systems.

  8. Plant nuclear factor Y (NF-Y) B subunits confer drought tolerance and lead to improved corn yields on water-limited acres.

    Science.gov (United States)

    Nelson, Donald E; Repetti, Peter P; Adams, Tom R; Creelman, Robert A; Wu, Jingrui; Warner, David C; Anstrom, Don C; Bensen, Robert J; Castiglioni, Paolo P; Donnarummo, Meghan G; Hinchey, Brendan S; Kumimoto, Roderick W; Maszle, Don R; Canales, Roger D; Krolikowski, Katherine A; Dotson, Stanton B; Gutterson, Neal; Ratcliffe, Oliver J; Heard, Jacqueline E

    2007-10-16

    Commercially improved crop performance under drought conditions has been challenging because of the complexity of the trait and the multitude of factors that influence yield. Here we report the results of a functional genomics approach that identified a transcription factor from the nuclear factor Y (NF-Y) family, AtNF-YB1, which acts through a previously undescribed mechanism to confer improved performance in Arabidopsis under drought conditions. An orthologous maize transcription factor, ZmNF-YB2, is shown to have an equivalent activity. Under water-limited conditions, transgenic maize plants with increased ZmNF-YB2 expression show tolerance to drought based on the responses of a number of stress-related parameters, including chlorophyll content, stomatal conductance, leaf temperature, reduced wilting, and maintenance of photosynthesis. These stress adaptations contribute to a grain yield advantage to maize under water-limited environments. The application of this technology has the potential to significantly impact maize production systems that experience drought.

  9. Fish mucus metabolome reveals fish life-history traits

    Science.gov (United States)

    Reverter, M.; Sasal, P.; Banaigs, B.; Lecchini, D.; Lecellier, G.; Tapissier-Bontemps, N.

    2017-06-01

    Fish mucus has important biological and ecological roles such as defense against fish pathogens and chemical mediation among several species. A non-targeted liquid chromatography-mass spectrometry metabolomic approach was developed to study gill mucus of eight butterflyfish species in Moorea (French Polynesia), and the influence of several fish traits (geographic site and reef habitat, species taxonomy, phylogeny, diet and parasitism levels) on the metabolic variability was investigated. A biphasic extraction yielding two fractions (polar and apolar) was used. Fish diet (obligate corallivorous, facultative corallivorous or omnivorous) arose as the main driver of the metabolic differences in the gill mucus in both fractions, accounting for 23% of the observed metabolic variability in the apolar fraction and 13% in the polar fraction. A partial least squares discriminant analysis allowed us to identify the metabolites (variable important in projection, VIP) driving the differences between fish with different diets (obligate corallivores, facultative corallivores and omnivorous). Using accurate mass data and fragmentation data, we identified some of these VIP as glycerophosphocholines, ceramides and fatty acids. Level of monogenean gill parasites was the second most important factor shaping the gill mucus metabolome, and it explained 10% of the metabolic variability in the polar fraction and 5% in the apolar fraction. A multiple regression tree revealed that the metabolic variability due to parasitism in the polar fraction was mainly due to differences between non-parasitized and parasitized fish. Phylogeny and butterflyfish species were factors contributing significantly to the metabolic variability of the apolar fraction (10 and 3%, respectively) but had a less pronounced effect in the polar fraction. Finally, geographic site and reef habitat of butterflyfish species did not influence the gill mucus metabolome of butterflyfishes.

  10. B cell-derived transforming growth factor-β1 expression limits the induction phase of autoimmune neuroinflammation.

    Science.gov (United States)

    Bjarnadóttir, Kristbjörg; Benkhoucha, Mahdia; Merkler, Doron; Weber, Martin S; Payne, Natalie L; Bernard, Claude C A; Molnarfi, Nicolas; Lalive, Patrice H

    2016-10-06

    Studies in experimental autoimmune encephalomyelitis (EAE), a murine model of multiple sclerosis (MS), have shown that regulatory B cells modulate the course of the disease via the production of suppressive cytokines. While data indicate a role for transforming growth factor (TGF)-β1 expression in regulatory B cell functions, this mechanism has not yet been tested in autoimmune neuroinflammation. Transgenic mice deficient for TGF-β1 expression in B cells (B-TGF-β1 -/- ) were tested in EAE induced by recombinant mouse myelin oligodendrocyte glycoprotein (rmMOG). In this model, B-TGF-β1 -/- mice showed an earlier onset of neurologic impairment compared to their littermate controls. Exacerbated EAE susceptibility in B-TGF-β1 -/- mice was associated with augmented CNS T helper (Th)1/17 responses. Moreover, selective B cell TGF-β1-deficiency increased the frequencies and activation of myeloid dendritic cells, potent professional antigen-presenting cells (APCs), suggesting that B cell-derived TGF-β1 can constrain Th1/17 responses through inhibition of APC activity. Collectively our data suggest that B cells can down-regulate the function of APCs, and in turn encephalitogenic Th1/17 responses, via TGF-β1, findings that may be relevant to B cell-targeted therapies.

  11. Limitations of a hemolytic plaque assay for IgG-anti-IgG rheumatoid factor-producing cells.

    Science.gov (United States)

    Venn, A J; Dresser, D W

    1987-09-24

    An attempt has been made to develop a hemolytic plaque assay capable of detecting homophile IgG rheumatoid factor (RF)-producing cells. Anti-immunoglobulin allotype-developing reagents were used to distinguish between target and effector IgG. The hemolytic assay has been used to demonstrate an apparently high level of homophile IgM and IgG RF-producing cells in the spleens and lymph nodes of mice stimulated by LPS. However, it appears that a large proportion of the plaques obtained in these assays are due to an artefact resulting from cross-linking of target and effector molecules by the developing reagents. In the case of IgM RF the artefact depends on the presence of a small contamination of the target IgG by IgM, allowing cross-linking of target and effector IgM by the anti-mu-specific developing reagent. With the IgG RF, cross-reactivity of the rabbit anti-Ighb allotype-developing serum for the 'wrong' (Igha) allotype, normally undetectable, becomes sufficient to be biologically relevant when the developing antibody is complexed by being bound to its target (Ighb) allotype. Nevertheless anti-allotype reagents may afford an accurate means of detecting homophile IgG RF producing cells using other assay systems.

  12. Fishing strategies and tactics in the Javanese seiners fisheries

    OpenAIRE

    Potier, Michel; Petit, Didier

    1995-01-01

    Fishing strategies and tactics are related to the knowledge fishermen have about environment, to the behavior of the fish and to the socio-economical factors which affect the fishery. The fishermen knowledge is applied to the strategy (time scale from the trips - less than one month up to one year), and to the tactics which is the way fish are caught (time scale, fishing operations). The strategy of the Javanese fishermen is highly correlated with the monsoons regime. The alternation of these...

  13. Sarcopenic obesity: A probable risk factor for dose limiting toxicity during neo-adjuvant chemotherapy in oesophageal cancer patients.

    Science.gov (United States)

    Anandavadivelan, Poorna; Brismar, Torkel B; Nilsson, Magnus; Johar, Asif M; Martin, Lena

    2016-06-01

    Profound weight loss and malnutrition subsequent to severe dysphagia and cancer cachexia are cardinal symptoms in oesophageal cancer (OC). Low muscle mass/sarcopenia has been linked to toxicity during neo-adjuvant therapy in other cancers, with worser effects in sarcopenic obesity. In this study the association between sarcopenia and/or sarcopenic obesity and dose limiting toxicity (DLT) during cycle one chemotherapy in resectable OC patients was evaluated. Body composition was assessed from computed tomography scans of 72 consecutively diagnosed OC patients. Lean body mass and body fat mass were estimated. Patients were grouped as sarcopenic or non-sarcopenic based on pre-defined gender-specific cut-offs for sarcopenia, and as underweight/normal (BMI sarcopenia combined with overweight and obesity. DLT was defined as temporary reduction/delay or permanent discontinuation of drugs due to adverse effects. Odds ratios for developing toxicity were ascertained using multiple logistic regression. Of 72 patients, 85% (n = 61) were males. Sarcopenia and sarcopenic obesity were present in 31 (43%) and 10 (14%), respectively, prior to chemotherapy. Sarcopenic patients had significantly lower adipose tissue index (p = 0.02) compared to non-sarcopenic patients. Patients with DLT (n = 24) had lower skeletal muscle mass (p = 0.04) than those without DLT. Sarcopenic patients (OR = 2.47; 95% CI: 0.88-6.93) showed a trend towards increased DLT risk (p < 0.10). Logistic regression with BMI as an interaction term indicated higher DLT risk in sarcopenic patients with normal BMI (OR = 1.60; 95% CI 0.30-8.40), but was non-significant. In the sarcopenic obese, risk of DLT increased significantly (OR = 5.54; 95% CI 1.12-27.44). Sarcopenic and sarcopenic obese OC patients may be at a higher risk for developing DLT during chemotherapy compared to non-sarcopenic OC patients. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All

  14. Reinforcement of the Gas Barrier Properties of Polyethylene and Polyamide Through the Nanocomposite Approach: Key Factors and Limitations

    Directory of Open Access Journals (Sweden)

    Picard E.

    2015-02-01

    Full Text Available In this study, polyamide 6 (PA6 and polyethylene (PE nanocomposites were prepared from melt blending and a detailed characterization of the nanocomposite morphology and gas barrier properties was performed. The choice of the organoclay was adapted to each polymer matrix. Exfoliated morphology and improved gas transport properties were obtained by melt mixing the polar PA6 matrix and the organoclay, whereas a microcomposite with poor barrier properties was formed from the binary PE/organomodified clay mixture. Different modified polyethylenes were examined as compatibilizers for the polyethylene/organoclay system. The effect of compatibilizer molar mass, polarity and content was investigated on the clay dispersion and on the gas barrier properties. The optimal compatibilizer to clay weight ratio was found to be equal to 4 whatever the compatibilizer. However, a high degree of clay delamination was obtained with the high molar mass compatibilizer whereas highly swollen clay aggregates resulted from the incorporation of the low molar mass interfacial agents. Contrary to the PA based system, the barrier properties of PE nanocomposites were not directly related to the clay dispersion state but resulted also from the matrix/clay interfacial interactions. Oxidized wax was identified as a very promising interfacial agent and a step by step study was performed to optimize the gas transport properties of the systems based on PE, oxidized wax and organoclay. In particular, an interesting combination of oxidized wax and high molar mass maleic anhydride grafted polyethylene allowing dividing the gas permeability by a factor 2 in comparison with neat PE was proposed.

  15. Tumour necrosis factor-alpha blockers: potential limitations in the management of advanced endometriosis? A case report.

    Science.gov (United States)

    Shakiba, Khashayar; Falcone, Tommaso

    2006-09-01

    Several studies have shown that tumour necrosis factor (TNF)-alpha levels are increased in the peritoneal fluid of women with endometriosis, with correlation between TNF-alpha concentrations and the degree of disease. It is also likely that elevation of peritoneal fluids' TNF-alpha levels may play a role in the pathogenesis of infertility associated with endometriosis. Use of drugs such as etanercept, a TNF-alpha receptor immunoglobulin fusion protein which inhibits TNF-alpha activity, showed in an animal study to reduce the severity of the disease, and the size of endometriotic foci. TNF-alpha blockers were recommended as a possible new line of therapy for endometriosis. Our case involved a 35-year-old Para 0, with rheumatic arthritis and stage 4 endometriosis. After 6 years of constant use of etanercept, she showed no improvement of endometriosis as demonstrated at laparoscopy. However, she underwent a successful IVF after the first attempt. TNF-alpha-blocker medications might not be beneficial for patients with advanced endometriosis. However, we cannot exclude the possible effect of these medications on early-stage endometriosis, and further study is required. Some of the immunologic abnormalities in the pelvis of patients with endometriosis could be the consequence of the disease and not the cause, and possibly suppression of immune cells and their products may not have a major effect on endometriotic lesions at an advanced stage. This also could explain why suppression of TNF-alpha showed no effect on infertility. However, use of TNF-alpha-blockers before IVF might increase the success rate in advanced endometriosis.

  16. Mobility Limitations and Fall-Related Factors Contribute to the Reduced Health-Related Quality of Life in Older Adults With Chronic Musculoskeletal Pain.

    Science.gov (United States)

    Stubbs, Brendon; Schofield, Pat; Patchay, Sandhi

    2016-01-01

    To investigate (1) the prevalence of chronic musculoskeletal pain (CMP) among a sample of community-dwelling older adults and (2) health-related quality of life (HRQOL) in people with CMP, particularly the association with mobility limitations and falls-related factors. Overall, 295 (response rate 73.5%) community-dwelling older adults were recruited across 10 sites. CMP was assessed using recognized criteria. In the sample of people with CMP, a hierarchical multiple regression analysis was conducted with HRQOL as the dependent variable and a number of independent variables were then inserted into the model. After controlling for demographic and medical variables, mobility (timed up and go (TUG), walking aid use, sedentary behavior) and fall-related factors (falls history, balance confidence, concerns about consequences of falling) were inserted into the model at the second step and changes in adjusted R(2) noted. Within our sample of older adults, 52% had CMP (154/295). Compared to the group without CMP of similar age (n = 141), those with CMP had reduced HRQOL and profound mobility limitations and more falls risk factors (P falls explanatory variables increased the variance explained within HRQOL from 14% to 36% (adjusted R(2) change 20%) in those with CMP. Sedentary behavior, pain interference, concerns about the consequences of falling, falls history, TUG scores, and balance confidence all remained significant predictors of HRQOL in the fully adjusted model in the CMP sample. Older adults with CMP have pronounced mobility limitations and increased falls risk factors, and these are associated with a marked reduction in HRQOL. Future prospective research is required to build on this cross-sectional study. © 2014 World Institute of Pain.

  17. Histamine poisoning and control measures in fish and fishery products

    Directory of Open Access Journals (Sweden)

    Pierina eVisciano

    2014-09-01

    Full Text Available Histamine poisoning is one of the most common form of intoxication caused by the ingestion of fish and fishery products. Cooking, canning or freezing cannot reduce the levels of histamine because this compound is heat stable. All humans are susceptible to histamine and its effects can be described as intolerance or intoxication depending on the severity of the symptoms. The amount of histamine in food, the individual sensitivity and the detoxification activity in human organism represent the main factors affecting the toxicological response in consumers. Histamine is the only biogenic amine with regulatory limits set by European Legislation, up to a maximum of 200 mg/kg in fresh fish and 400 mg/kg in fishery products treated by enzyme maturation in brine.

  18. TH-EF-204-03: Determination of Small Field Output Factors, Advantages and Limitations of Monte Carlo Simulation

    International Nuclear Information System (INIS)

    Vaque, J. Puxeu

    2016-01-01

    dosimetry of conventional fields To learn about detectors suitable for small fields To learn about the role of Monte Carlo simulations in determination of small field output factors To provide an overview of the IAEA small field dosimetry recommendations To provide an overview of the content of the ICRU report on Prescribing, Reporting and Recording of Small Field Radiation Therapy. To learn about special technical considerations in delivering IMRT and SBRT treatments To appreciate specific challenges of IMRT implementation J. Seuntjens, Natural Sciences and Engineering Research Council; Canadian Institutes of Health Research

  19. TH-EF-204-03: Determination of Small Field Output Factors, Advantages and Limitations of Monte Carlo Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Vaque, J. Puxeu [Institut Catala d’Oncologia (Spain)

    2016-06-15

    dosimetry of conventional fields To learn about detectors suitable for small fields To learn about the role of Monte Carlo simulations in determination of small field output factors To provide an overview of the IAEA small field dosimetry recommendations To provide an overview of the content of the ICRU report on Prescribing, Reporting and Recording of Small Field Radiation Therapy. To learn about special technical considerations in delivering IMRT and SBRT treatments To appreciate specific challenges of IMRT implementation J. Seuntjens, Natural Sciences and Engineering Research Council; Canadian Institutes of Health Research.

  20. Spoilage and shelf-life extension of fresh fish and shellfish.

    Science.gov (United States)

    Ashie, I N; Smith, J P; Simpson, B K

    1996-01-01

    Fresh fish and shellfish are highly perishable products due to their biological composition. Under normal refrigerated storage conditions, the shelf life of these products is limited by enzymatic and microbiological spoilage. However, with increasing consumer demands for fresh products with extended shelf life and increasing energy costs associated with freezing and frozen storage, the fish-processing industry is actively seeking alternative methods of shelf life preservation and marketability of fresh, refrigerated fish and at the same time economizing on energy costs. Additional methods that could fulfill these objectives include chemical decontamination, low-dose irradiation, ultra-high pressure, and modified atmosphere packaging (MAP). This review focuses on the biochemical and microbiological composition of fresh fish/shellfish, the spoilage patterns in these products, factors influencing spoilage, and the combination treatments that can be used in conjunction with refrigeration to extend the shelf life and keeping quality of fresh fish/shellfish. The safety concerns of minimally processed/MAP fish, specifically with respect to the growth of Clostridium botulinum type E, is also addressed.

  1. Crucial knowledge gaps in current understanding of climate change impacts on coral reef fishes

    KAUST Repository

    Wilson, S. K.

    2010-02-26

    Expert opinion was canvassed to identify crucial knowledge gaps in current understanding of climate change impacts on coral reef fishes. Scientists that had published three or more papers on the effects of climate and environmental factors on reef fishes were invited to submit five questions that, if addressed, would improve our understanding of climate change effects on coral reef fishes. Thirty-three scientists provided 155 questions, and 32 scientists scored these questions in terms of: (i) identifying a knowledge gap, (ii) achievability, (iii) applicability to a broad spectrum of species and reef habitats, and (iv) priority. Forty-two per cent of the questions related to habitat associations and community dynamics of fish, reflecting the established effects and immediate concern relating to climate-induced coral loss and habitat degradation. However, there were also questions on fish demographics, physiology, behaviour and management, all of which could be potentially affected by climate change. Irrespective of their individual expertise and background, scientists scored questions from different topics similarly, suggesting limited bias and recognition of a need for greater interdisciplinary and collaborative research. Presented here are the 53 highest-scoring unique questions. These questions should act as a guide for future research, providing a basis for better assessment and management of climate change impacts on coral reefs and associated fish communities.

  2. [Fish intake and risk of prostate cancer].

    Science.gov (United States)

    Dybkowska, Ewa; Świderski, Franciszek; Waszkiewicz-Robak, Bożena

    2014-10-17

    The aim of the study was to present the current state of knowledge concerning the relationship between the consumption of fish as materials rich in long chain polyunsaturated fatty acids (LC PUFA) omega-3, and the risk of prostate cancer. Many scientific reports confirm the health benefits from the consumption of fish and protective properties of LC PUFA omega-3 in relation to prostate cancer. However, there are reports that indicate a relationship of the high consumption of PUFA with the risk of prostate cancer. The way of processing and preservation of the fish, and other factors not included in previous studies, could have some importance in the etiology of this disease. High susceptibility of PUFA to oxidation changes and the technological fish processing (smoking, high-temperature cooking methods) contribute to the formation of many compounds, such as polycyclic aromatic hydrocarbons and heterocyclic amines - which may influence the formation of cancers - including prostate cancer. It is necessary to ensure an adequate amount of LC PUFA omega-3 in the diet through the consumption of proper quality fish and fish oils. Particular attention should be paid to the high susceptibility of PUFA to the oxidative processes, and the method of processing, preservation and storage of fish. Also pollution from the environment can significantly reduce the impact of health benefits of PUFA and fish, and even be the cause of cancers, including prostate cancer. Further research in this area should be more targeted to assess the impact of nutritional factors for the development of such tumors.

  3. Fish allergens at a glance: variable allergenicity of parvalbumins, the major fish allergens.

    Science.gov (United States)

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1) isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases, and fish gelatin, seem to be important allergens. New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings were useful for the advancement of the IgE-based diagnosis and also for the management of fish allergies consisting of advice and treatment of fish-allergic patients.

  4. Fish allergens at a glance: Variable allergenicity of parvalbumins, the major fish allergens

    Directory of Open Access Journals (Sweden)

    Annette eKuehn

    2014-04-01

    Full Text Available Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1 isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases and fish gelatin, seem to be important allergens.New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings will be useful for the advancement of the IgE-based diagnosis but also for the management of fish allergies consisting of advice and treatment of fish-allergic patients.

  5. Potential hazards in smoke-flavored fish

    Science.gov (United States)

    Lin, Hong; Jiang, Jie; Li, Donghua

    2008-08-01

    Smoking is widely used in fish processing for the color and flavor. Smoke flavorings have evolved as a successful alternative to traditional smoking. The hazards of the fish products treated by liquid-smoking process are discussed in this review. The smoke flavoring is one important ingredient in the smoke-flavored fish. This paper gives the definition of smoke flavorings and the hazard of polycyclic aromatic hydrocarbons (PAHs) residue in the smoke flavorings on the market. It gives also an assessment of chemical hazards such as carcinogenic PAHs, especially Benzo-[ a]pyrene, as well as biological hazards such as Listeria monocytogenes, Clostridium botulinum, histamine and parasites in smoke-flavored fish. The limitations in regulations or standards are discussed. Smoke flavored fish have lower content of PAHs as compared with the traditional smoking techniques if the PAHs residue in smoke flavorings is controlled by regulations or standards.

  6. Democracy as a Limiting Factor for Politicised Cultural Populism in Malawi Demokratie und politisierter Kulturpopulismus in Malawi

    Directory of Open Access Journals (Sweden)

    Reuben Makayiko Chirambo

    2009-01-01

    Full Text Available Though Malawian democracy could still be described as in transition from authoritarianism, it has enabled an atmosphere for critical debate of and dissent against seemingly popular opinions, which was not possible during the authoritarian rule of former life president, Dr. H. K. Banda, 1964-1994. This article examines politicised cultural populism in Malawi under the dictatorship and democracy in comparative terms. President Banda, as a political populist, appropriated culture to legitimate and validate his political power as well as to cultivate popular support from the majority of ordinary people. Following reforms towards democracy since 1992, his successors have also tended towards populist politics by similarly appropriating culture and cultural activities, among other means, to cultivate popular support from mostly ordinary people for their regimes. Such politicised cultural populism involves adopting traditional roles, cultural symbols and images of power such as praise-titles, and participating in cultural activities such as traditional dances. This article examines the efforts of President Bingu wa Mutharika in the democratic dispensation to appropriate cultural artefacts used by Banda during a dictatorship in order to cultivate popular support for his regime. The article argues that Bingu’s efforts at politicised cultural populism are constrained, among other factors, by the nature and climate of democratic politics mainly because democracy, unlike a dictatorship, enables critical debate and the questioning of political leader’s behaviour and their motives. Auch wenn die Demokratie in Malawi sich immer noch in einem Übergangsstadium befindet, ist inzwischen eine Atmosphäre entstanden, in der eine kritische Debatte und das Äußern unpopulärer Meinungen möglich sind, was in den Jahren 1964-1994 unter dem früheren Präsidenten auf Lebenszeit, Dr. H. K. Banda, nicht denkbar war. Der Autor vergleicht die Nutzung von Elementen

  7. Effectiveness of enforcement levels of speed limit and drink driving laws and associated factors – Exploratory empirical analysis using a bivariate ordered probit model

    Directory of Open Access Journals (Sweden)

    Behram Wali

    2017-06-01

    Full Text Available The contemporary traffic safety research comprises little information on quantifying the simultaneous association between drink driving and speeding among fatally injured drivers. Potential correlation between driver's drink driving and speeding behavior poses a substantial methodological concern which needs investigation. This study therefore focused on investigating the simultaneous impact of socioeconomic factors, fatalities, vehicle ownership, health services and highway agency road safety policies on enforcement levels of speed limit and drink driving laws. The effectiveness of enforcement levels of speed limit and drink driving laws has been investigated through development of bivariate ordered probit model using data extricated from WHO's global status report on road safety in 2013. The consistent and intuitive parameter estimates along with statistically significant correlation between response outcomes validates the statistical supremacy of bivariate ordered probit model. The results revealed that fatalities per thousand registered vehicles, hospital beds per hundred thousand population and road safety policies are associated with a likely medium or high effectiveness of enforcement levels of speed limit and drink driving laws, respectively. Also, the model encapsulates the effect of several other agency related variables and socio-economic status on the response outcomes. Marginal effects are reported for analyzing the impact of such factors on intermediate categories of response outcomes. The results of this study are expected to provide necessary insights to elemental enforcement programs. Also, marginal effects of explanatory variables may provide useful directions for formulating effective policy countermeasures for overcoming driver's speeding and drink driving behavior.

  8. Fish Welfare in Aquaponic Systems: Its Relation to Water Quality with an Emphasis on Feed and Faeces—A Review

    Directory of Open Access Journals (Sweden)

    Hijran Yavuzcan Yildiz

    2017-01-01

    Full Text Available Aquaponics is the combination of aquaculture (fish and hydroponic cultivation of plants. This review examines fish welfare in relation to rearing water quality, fish feed and fish waste and faeces to develop a sustainable aquaponic system where the co-cultured organisms, fish, bacteria in biofilters and plants, should be considered holistically in all aquaponics operations. Water quality parameters are the primary environmental consideration for optimizing aquaponic production and for directly impacting fish welfare/health issues and plant needs. In aquaponic systems, the uptake of nutrients should be maximised for the healthy production of the plant biomass but without neglecting the best welfare conditions for the fish in terms of water quality. Measures to reduce the risks of the introduction or spread of diseases or infection and to increase biosecurity in aquaponics are also important. In addition, the possible impacts of allelochemicals, i.e., chemicals released by the plants, should be taken into account. Moreover, the effect of diet digestibility, faeces particle size and settling ratio on water quality should be carefully considered. As available information is very limited, research should be undertaken to better elucidate the relationship between appropriate levels of minerals needed by plants, and fish metabolism, health and welfare. It remains to be investigated whether and to what extent the concentrations of suspended solids that can be found in aquaponic systems can compromise the health of fish. Water quality, which directly affects fish health and well-being, is the key factor to be considered in all aquaponic systems.

  9. Electric-dipole-moment enhancement factor for the thallium atom, and a new upper limit on the electric dipole moment of the electron

    International Nuclear Information System (INIS)

    Sandars, P.G.H.; Sternheimer, R.M.

    1975-01-01

    Some time ago, an accurate upper limit on a possible permanent electric dipole moment of the thallium atom in the 6 2 P 1 / 2 ground state was obtained by Gould. The result was D/sub Tl/ = [(1.3 +- 2.4) x 10 -21 cm]e. In connection with this value, a calculation of the electric dipole enhancement factor R/sub Tl/, which is defined as the ratio D/sub Tl//D/sub e/, where D/sub e/is the corresponding upper limit on a possible electric dipole moment of the (valence) electron was carried out. A value R/subTl/ = 700 was obtained, which leads to an upper limit D/sub e/ = [(1.9 +- 3.4) x 10 -24 cm]e. This result is comparable with the value D/sub e/ -24 cm)e previously obtained by Weisskopf et al. from measurements on the cesium atom, and with the result of Player and Sandars of [(0.7 +- 2.2) x 10 -24 cm]e obtained from the search for an electric dipole moment in the 3 P 2 metastable state of xenon. All three results set a stringent upper limit on the amount of a possible violation of T and P invariance in electromagnetic interactions. (U.S.)

  10. Mercury in fishes from Wrangell-St. Elias National Park and Preserve, Alaska

    Science.gov (United States)

    Kowalski, Brandon M.; Willacker, James J.; Zimmerman, Christian E.; Eagles-Smith, Collin A.

    2014-01-01

    In this study, mercury (Hg) concentrations were examined in fishes from Wrangell-St. Elias National Park and Preserve, Alaska, the largest and one of the most remote units in the national park system. The goals of the study were to (1) examine the distribution of Hg in select lakes of Wrangell-St. Elias National Park and Preserve; (2) evaluate the differences in Hg concentrations among fish species and with fish age and size; and (3) assess the potential ecological risks of Hg to park fishes, wildlife, and human consumers by comparing Hg concentrations to a series of risk benchmarks. Total Hg concentrations ranged from 17.9 to 616.4 nanograms per gram wet weight (ng/g ww), with a mean (± standard error) of 180.0 ±17.9 across the 83 individuals sampled. Without accounting for the effects of size, Hg concentrations varied by a factor of 10.9 across sites and species. After accounting for the effects of size, Hg concentrations were even more variable, differing by a factor of as much as 13.2 within a single species sampled from two lakes. Such inter-site variation suggests that site characteristics play an important role in determining fish Hg concentrations and that more intensive sampling may be necessary to adequately characterize Hg contamination in the park. Size-normalized Hg concentrations also differed among three species sampled from Tanada Lake, and Hg concentrations were strongly correlated with age. Furthermore, potential risks to park fish, wildlife, and human users were variable across lakes and species. Although no fish from two of the lakes studied (Grizzly Lake and Summit Lake) had Hg concentrations exceeding any of the benchmarks used, concentrations in Copper Lake and Tanada Lake exceeded conservative benchmarks for bird (90 ng/g ww in whole-body) and human (150 ng/g ww in muscle) consumption. In Ta