WorldWideScience

Sample records for nonoptimal growth conditions

  1. The growth response of plants to elevated CO2 under non-optimal environmental conditions

    NARCIS (Netherlands)

    Poorter, H.; Pérez-Soba, M.

    2001-01-01

    Under benign environmental conditions, plant growth is generally stimulated by elevated atmospheric CO2 concentrations. When environmental conditions become sub- or supra-optimal for growth, changes in the biomass enhancement ratio (BER; total plant biomass at elevated CO2 divided by plant biomass

  2. Evaluation of two methods DNA extraction from formalin-fixed, paraffin-embedded tissues on non-optimal conditions

    International Nuclear Information System (INIS)

    Bustamante, Javier Andres; Astudillo, Miryam; Pazos, Alvaro Jairo; Bravo, Luis Eduardo

    2011-01-01

    Paraffin wax embedded tissues are an invaluable material for retrospective studies requiring the application of molecular analysis. Multiple methods are available to extract DNA from these kinds of samples. However, the most common methods are slow and the reagents often contribute to the fragmentation of genetic material. In order to optimize the procedure, two methods for DNA extraction from paraffin embedded tissue non-optimal conditions were used. 47 blocks containing paraffin-embedded biopsies of pleura, lung and pericardium from 24 patients (66.6% males) older than 18 years, with biopsy proven chronic granulomatous inflammation referred to the department of pathology at University Hospital of Valle between 2002 and 2007 were selected. Each sample was subjected to 10 cuts and was to two methods of DNA extraction: 1. conventional and 2. QIAamp - DNA mini kit. The efficiency of the extracted DNA was assessed by spectrophotometry and PCR amplification of a fragment of the housekeeping gene GAPDH. The concentration of DNA samples extracted by the conventional method was of 65.52 ng/Mu l ± 11.47 (mean ± SE) and the 260/280 absorbance ratio ranged between 0.52 and 2.30 the average concentration of DNA of the samples extracted by the commercial method was 60.89 ng/Mu l ± 6.02 (mean ± SE), with an absorbance that fluctuated between 0 and 2.64. The DNA obtained was amplified by PCR, of 47 samples extracted by methods, 25 and 23 respectively the GAPDH gene amplified successfully. The methods used to obtain DNA showed similar performance, highlighting the potential utility of both extraction methods for the retrospective studies from paraffin embedded tissues in unsuitable conditions.

  3. Conditioning biomass for microbial growth

    Science.gov (United States)

    Bodie, Elizabeth A; England, George

    2015-03-31

    The present invention relates to methods for improving the yield of microbial processes that use lignocellulose biomass as a nutrient source. The methods comprise conditioning a composition comprising lignocellulose biomass with an enzyme composition that comprises a phenol oxidizing enzyme. The conditioned composition can support a higher rate of growth of microorganisms in a process. In one embodiment, a laccase composition is used to condition lignocellulose biomass derived from non-woody plants, such as corn and sugar cane. The invention also encompasses methods for culturing microorganisms that are sensitive to inhibitory compounds in lignocellulose biomass. The invention further provides methods of making a product by culturing the production microorganisms in conditioned lignocellulose biomass.

  4. Caffeine Enhances Memory Performance in Young Adults during Their Non-optimal Time of Day.

    Science.gov (United States)

    Sherman, Stephanie M; Buckley, Timothy P; Baena, Elsa; Ryan, Lee

    2016-01-01

    Many college students struggle to perform well on exams in the early morning. Although students drink caffeinated beverages to feel more awake, it is unclear whether these actually improve performance. After consuming coffee (caffeinated or decaffeinated), college-age adults completed implicit and explicit memory tasks in the early morning and late afternoon (Experiment 1). During the morning, participants ingesting caffeine demonstrated a striking improvement in explicit memory, but not implicit memory. Caffeine did not alter memory performance in the afternoon. In Experiment 2, participants engaged in cardiovascular exercise in order to examine whether increases in physiological arousal similarly improved memory. Despite clear increases in physiological arousal, exercise did not improve memory performance compared to a stretching control condition. These results suggest that caffeine has a specific benefit for memory during students' non-optimal time of day - early morning. These findings have real-world implications for students taking morning exams.

  5. Caffeine enhances memory performance in young adults during their non-optimal time of day

    Directory of Open Access Journals (Sweden)

    Stephanie M Sherman

    2016-11-01

    Full Text Available Many college students struggle to perform well on exams in the early morning. Although students drink caffeinated beverages to feel more awake, it is unclear whether these actually improve performance. After consuming coffee (caffeinated or decaffeinated, college-age adults completed implicit and explicit memory tasks in the early morning and late afternoon (Experiment 1. During the morning, participants ingesting caffeine demonstrated a striking improvement in explicit memory, but not implicit memory. Caffeine did not alter memory performance in the afternoon. In Experiment 2, participants engaged in cardiovascular exercise in order to examine whether increases in physiological arousal similarly improved memory. Despite clear increases in arousal, exercise did not improve memory performance compared to a stretching control condition. These results suggest that caffeine has a specific benefit for memory during students’ non-optimal time of day – early morning. These findings have real-world implications for students taking morning exams.

  6. CAUSES OF NON-OPTIMAL CONSERVATIVE TREATMENT OF CONGENITAL CLUBFOOT IN CHILDREN

    Directory of Open Access Journals (Sweden)

    V. M. Kenis

    2017-01-01

    Full Text Available Introduction. Ponseti method commonly accepted as the optimal approach to management of congenital clubfoot. Continuing with alternative methods should considered as malpractice. Aim: to assess causes of non-optimal treatment of congenital clubfoot in children.Materials and methods: Assessment group included 60 patients treated earlier in other clinics with non-optimal results. Control group included 60 patients treated in our clinic by Ponseti method. We used case history analysis and parents’ interviewing.Results. Family history of clubfoot and prenatal diagnosis positively influenced on the choice of Ponseti method. Primary consultancy of orthopedist and Internet search were main factors for choosing Ponseti method after birth. In contrast, the methods lead to non-optimal results chosen after maternity home and pediatricians.Conclusion. Main cause of non-optimal results of congenital clubfoot treatment is the lack of information regarding current approaches among non-orthopedic physicians, which emphasizes necessity of adequate informational support.

  7. Optimal growth conditions for Isochrysis galbana

    Energy Technology Data Exchange (ETDEWEB)

    Kaplan, D; Cohen, Z; Abeliovich, A

    1986-01-01

    Environmental and nutritional growth conditions of the unicellular microalga Isochrysis galbana were studied under laboratory conditions. The information obtained was used for cultivating the alga in outdoor miniponds. Outdoor cultures stayed monoalgal and free of predators as long as the temperature did not fall below 19 degrees C and the rate of dilution did not exceed 40% of the culture's volume. Isochrysis galbana grown in outdoor cultures provided lipid concentrations of 24-28% of ash free dry matter. 12 references.

  8. Changes In Growth Culture FDA Activity Under Changing Growth Conditions

    DEFF Research Database (Denmark)

    Jørgensen, Per Elberg; Eriksen, Thomas Juul; Jensen, Bjørn K.

    1992-01-01

    The FDA hydrolysis capacities and bacterial biomass concentrations (estimated by determination of ATP content) of growth cultures prepared from activated sludge and wastewater, were measured to find out whether the FDA activity would reflect bacterial biomass under different physiological states...... of the bacteria. The FDA activity/ATP ratio was calculated for different concentrations of autoclaved sludge. A faster decay rate of ATP relative to FDA hydrolysis activity was observed, thus causing changes in the ratio. Furthermore, comparison between values obtained from pure cultures and different soils...... revealed differences up to two orders of magnitude of the ratio. Based on these results it was concluded that the FDA activity should not be applied for measurements of viable biomass in environments in which different physiological conditions occur....

  9. Growth conditions of 0-group plaice

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; Freitas, V.; de Paoli, H.; Witte, J.IJ.; van der Veer, H.W.

    2016-01-01

    Growth studies based on population-based growth estimates are limited by the fact that they do not take into account differences in age/size structure within the population. To overcome these problems, otolith microstructure analysis is often used to estimate individual growth. Here, we analyse

  10. Achieving Revenue Benchmarks Conditional on Growth Properties

    Directory of Open Access Journals (Sweden)

    Dong Hyun Son

    2017-05-01

    Full Text Available This study examines whether certain firm characteristics, specifically growth properties, are associated with the likelihood of achieving market expectations for revenues, as well as which mechanism (revenue manipulation or expectation management growth firms utilize in order to avoid missing these expectations. The results show that growth firms are more likely to meet or exceed analyst revenue forecasts than non-growth firms. We also find that growth firms are more inclined to manipulate their reported revenues upwards, and less inclined to guide market expectations for revenues downward, in order to meet or beat expected revenues relative to non-growth firms. These findings suggest that window-dressing activities by growth firms may not be sustainable in the long-run and can misguide users of financial statements in their decision-making.

  11. Implicit Learning of Complex Visual Contexts Under Non-Optimal Conditions

    National Research Council Canada - National Science Library

    Jiang, Yuhong V

    2007-01-01

    .... We can recognize an object or a face in a single glimpse and type 70 words per minute, yet we cannot hold more than a few objects at a time in visual working memory or split our attention to several locations...

  12. Growth of Corophium volutator under laboratory conditions

    NARCIS (Netherlands)

    Kater, B.J.; Jol, J.G.; Smit, M.G.D.

    2008-01-01

    Temperature-dependent growth is an important factor in the population model of Corophium volutator that was developed to translate responses in a 10-day acute bioassay to ecological consequences for the population. The growth rate, however, was estimated from old data, based on a Swedish population.

  13. Study on growth condition of Trichoderma mutants

    International Nuclear Information System (INIS)

    Chen Jian'ai; Xiao Min; Wang Weiming; Chen Weijing; Sun Yongtang

    2002-01-01

    Some Trichoderma mutants were cultured under different conditions 4 strains, T5, T0803, T1010, T1003 were selected with different mediums and every medium was mixed with fungicide of 40 ppm. The fungicides were procymidone + chlorothalonil, maneb and phosethyl-Al. The pH of medium were 5, 6, 7 and 8, respectively. The growing temperatures were 15, 20, 25 and 30 degree C, respectively. After the hypha growing for some days under natural high temperature, they were put in low temperature for producing spores. The growing times for these hypha were 3,4,5 and 6 days, respectively. All dates were analyzed on statistics with the orthogonal array and ranges (R) were different with different factor and levels (R = 40.4, 42.4, 48.0, 62.8, 107.0). The results showed that the strain was the most influent condition (R = 107.0) and the changed temperature time from high to low was the least influent condition (R = 40.4). Each factor variance was significant and A 3 b 4 C 2 D 1 E 3 was the optimum combined condition, under which T1010 grew more quickly and produced the most spores

  14. Eutectic growth under acoustic levitation conditions.

    Science.gov (United States)

    Xie, W J; Cao, C D; Lü, Y J; Wei, B

    2002-12-01

    Samples of Pb-Sn eutectic alloy with a high density of 8.5 x 10(3) kg/m(3) are levitated with a single-axis acoustic levitator, and containerlessly melted and then solidified in argon atmosphere. High undercoolings up to 38 K are obtained, which results in a microstructural transition of "lamellas-broken lamellas-dendrites." This transition is further investigated in the light of the coupled zone for eutectic growth and the effects of ultrasound. The breaking of regular eutectic lamellas and suppression of gravity-induced macrosegregation of (Pb) and (Sn) dendrites are explained by the complicated internal flow inside the levitated drop, which is jointly induced by the shape oscillation, bulk vibration and rotation of the levitated drop. The ultrasonic field is also found to drive forced surface vibration, which subsequently excites capillary ripples and catalyzes nucleation on the sample surface.

  15. Genes adopt non-optimal codon usage to generate cell cycle-dependent oscillations in protein levels

    DEFF Research Database (Denmark)

    Frenkel-Morgenstern, Milana; Danon, Tamar; Christian, Thomas

    2012-01-01

    The cell cycle is a temporal program that regulates DNA synthesis and cell division. When we compared the codon usage of cell cycle-regulated genes with that of other genes, we discovered that there is a significant preference for non-optimal codons. Moreover, genes encoding proteins that cycle a...

  16. Conditions for mould growth on typical interior surfaces

    DEFF Research Database (Denmark)

    Møller, Eva B.; Andersen, Birgitte; Rode, Carsten

    2017-01-01

    Prediction of the risk for mould growth is an important parameter for the analysis and design of the hygrothermal performance of building constructions. However, in practice the mould growth does not always follow the predicted behavior described by the mould growth models. This is often explained...... by uncertainty in the real conditions of exposure. In this study, laboratory experiments were designed to determine mould growth at controlled transient climate compared to growth at constant climate. The experiment included three building materials with four different surface treatments. The samples were...

  17. Analytical Diagnostics of Non-Optimal Use of Pesticides and Health Hazards for Vegetable Pickers

    International Nuclear Information System (INIS)

    Zafar, M.; Mehmood, T.; Baig, I. A.; Saboor, A.; Sadiq, S.; Mahmood, K.

    2016-01-01

    Economically pesticides are meant to control pests in the fields. Up to certain optimal use of a typical pesticide, it enhances the yield of crops and vegetables. But, eventually amplified use of pesticides results in contamination of environment (water, soil, and air) and increase the health cost of vegetable pickers. The purpose of this study is to estimate the excessive use of pesticides and economic cost of health hazards for the vegetable pickers in district Vehari. Data from 90 respondents were collected and analyzed. The most common health problems identified during the survey were headache, eye irritation, skin infection, cough and shortness of breath. Health cost consists of costs related to precautionary measure, medication, traveling, the opportunity cost of attended persons and productivity loss. The mean health cost of vegetable pickers in the study area was about Rs. 385 per picker per year. Health cost model was used to measure the health cost of vegetable pickers. The regression results showed that pesticides were being applied non-optimally in the study area i.e., number of pesticide applications for vegetables (7-31) were substantially higher than the recommended dose. Health cost function was significantly different from zero as indicated by F-stat (32.18) and it is also supported by R/sup 2/ that about 70 percent variation in health cost is explained by medication accompanied by productivity loss (Rs. 223), precautionary measure (Rs. 134), attended person cost (Rs. 14) and traveling expenditures (Rs. 16). Hence, strict legislation is required to overcome the availability of hazardous pesticides and to keep the vegetable pickers aware of the optimal use of pesticides through appropriate extension services. (author)

  18. A theory of economic growth with material/energy resources and dematerialization. Interaction of three growth mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Ayres, Robert U. [Department of Physical Resource Theory, Chalmers Institute, Gothenburg (Sweden); Van den Bergh, Jeroen C.J.M. [Department of Spatial Economics, Faculty of Economics and Business Administration, and Institute for Environmental Studies, Free University, De Boelelaan 1105, Amsterdam 1081 HV (Netherlands)

    2005-10-05

    The nature of energy and material resources in a non-optimizing growth theory framework is clarified. This involves two modifications of the conventional theory. Firstly, multiple feedback mechanisms or 'growth engines' are identified, such that the impact of the cost of production through demand on growth is accounted for. Secondly, a production function distinguishes between resource use, technical efficiency, and value creation. The resulting model is analytically solved under the condition of a constant growth rate. Given model complexity, numerical experiments are performed as well, providing relevant insights to the academic and political debates on 'environmental Kuznets curves' and 'dematerialization.'.

  19. Convex variational problems linear, nearly linear and anisotropic growth conditions

    CERN Document Server

    Bildhauer, Michael

    2003-01-01

    The author emphasizes a non-uniform ellipticity condition as the main approach to regularity theory for solutions of convex variational problems with different types of non-standard growth conditions. This volume first focuses on elliptic variational problems with linear growth conditions. Here the notion of a "solution" is not obvious and the point of view has to be changed several times in order to get some deeper insight. Then the smoothness properties of solutions to convex anisotropic variational problems with superlinear growth are studied. In spite of the fundamental differences, a non-uniform ellipticity condition serves as the main tool towards a unified view of the regularity theory for both kinds of problems.

  20. Modified atmospheric conditions controlling fungal growth on cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose

    1997-01-01

    Effective control of fungal growth on cheese under storage conditions is of great concern for the dairy industry. Therefore we designed a research project together with the Danish dairy industry on modelling fungal growth on cheese as affected by the combined effect of storage conditions (O2 and CO......2 level, relative humidity and temperature) and the composition of the cheese. All fungal species commonly found on cheese, starter cultures as well as contaminants, were examined.The most important factors influencing fungal growth are temperature, water activity of the medium and the carbon...... a competitive advantage over other fungi in moist conditions with high carbon dioxide levels, such as inside a roquefort cheese or in gas tight grain storage. The key to success in food packaging is to recognise the food ecosystem, as it enables us to identify which micro...

  1. Technical conditions for sustainable growth in economic theory. An analysis

    International Nuclear Information System (INIS)

    Granda C, Catalina

    2008-01-01

    Economic theory and its models point out returns to scale, substitution among productive factors and technological progress as conditions for sustainable growth. This work aims at a critical appraisal of these conditions, particularly the ones related to substitution between natural resources and manmade capital and technical change, by recognizing the inevitable physical scarcity of resources concomitant to the human actions in a world governed by hemodynamic restrictions. To do so, the role that the mentioned conditions play in the theories of economic growth with resources is analyzed, and its limitations and objections from a biophysical perspective are indicated as well. Finally, a brief consideration as to how inappropriate the theoretical representations of economic activities are to take account of growth in spite of resource exhaustion or degradation is carried out

  2. Optimization of growth medium and fermentation conditions for ...

    African Journals Online (AJOL)

    A sequential optimization approach based on statistical experimental designs was employed to optimize growth medium and fermentation conditions, in order to improve the antibiotic activity of Xenorhabdus nematophila TB. Tryptone soyptone broth (TSB) was chosen as the original medium for optimization. Glucose and ...

  3. Optimizing growth conditions for electroless deposition of Au films ...

    Indian Academy of Sciences (India)

    Unknown

    Optimizing growth conditions for electroless deposition of Au films on. Si(111) substrates. BHUVANA and G U KULKARNI*. Chemistry and Physics of Materials Unit and DST Unit on Nanoscience, Jawaharlal Nehru Centre for. Advanced Scientific Research, Jakkur PO, Bangalore 560 064, India. MS received 24 March 2006.

  4. Comparison of traditional low-dose-rate to optimized and nonoptimized high-dose-rate tandem and ovoid dosimetry

    International Nuclear Information System (INIS)

    Decker, William E.; Erickson, Beth; Albano, Katherine; Gillin, Michael

    2001-01-01

    Purpose: Few dose specification guidelines exist when attempting to perform high-dose-rate (HDR) dosimetry. The purpose of this study was to model low-dose-rate (LDR) dosimetry, using parameters common in HDR dosimetry, to achieve the 'pear-shape' dose distribution achieved with LDR tandem and ovoid applications. Methods and Materials: Radiographs of Fletcher-Suit LDR applicators and Nucletron 'Fletcher-like' HDR applicators were taken with the applicators in an idealized geometry. Traditional Fletcher loadings of 3M Cs-137 sources and the Theratronics Planning System were used for LDR dosimetry. HDR dosimetry was performed using the Nucletron Microselectron HDR UPS V11.22 with an Ir-192 source. Dose optimization points were initially located along a line 2 cm lateral to the tandem, beginning at the tandem tip at 0.5-cm intervals, ending at the sail, and optimized to 100% of the point A dose. A single dose optimization point was also placed laterally from the center of each ovoid equal to the radius of the ovoid (ovoid surface dose). For purposes of comparison, dose was also calculated for points A and B, and a point located 1 cm superior to the tandem tip in the plane of the tandem, (point F). Four- and 6-cm tandem lengths and 2.0-, 2.5-, and 3.0-cm ovoid diameters were used for this study. Based on initial findings, dose optimization schemes were developed to best approximate LDR dosimetry. Finally, radiographs were obtained of HDR applications in two patients. These radiographs were used to compare the optimization schemes with 'nonoptimized' treatment plans. Results: Calculated doses for points A and B were similar for LDR, optimized HDR, and nonoptimized HDR. The optimization scheme that used tapered dose points at the tandem tip and optimized a single ovoid surface point on each ovoid to 170% of point A resulted in a good approximation of LDR dosimetry. Nonoptimized HDR resulted in higher doses at point F, the bladder, and at points lateral to the tandem tip

  5. Methods of forecasting crack growth rate under creep conditions

    International Nuclear Information System (INIS)

    Ol'kin, S.I.

    1979-01-01

    Using construction aluminium alloy application possibility of linear mechanics of the destruction for quantitative description of crack development process under creepage conditions is investigated. It is shown, that the grade dependence between the stress intensity coefficient and the crack growth rate takes place only at certain combination of the sample geometry and creepage parameters, and consequently, its applicability in every given case must necessarily be tested experimentally

  6. Selective area growth of GaN rod structures by MOVPE: Dependence on growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Li, Shunfeng; Fuendling, Soenke; Wang, Xue; Erenburg, Milena; Al-Suleiman, Mohamed Aid Mansur; Wei, Jiandong; Wehmann, Hergo-Heinrich; Waag, Andreas [Institut fuer Halbleitertechnik, TU Braunschweig, Hans-Sommer-Strasse 66, 38106 Braunschweig (Germany); Bergbauer, Werner [Institut fuer Halbleitertechnik, TU Braunschweig, Hans-Sommer-Strasse 66, 38106 Braunschweig (Germany); Osram Opto Semiconductors GmbH, Leibnizstr. 4, 93055 Regensburg (Germany); Strassburg, Martin [Osram Opto Semiconductors GmbH, Leibnizstr. 4, 93055 Regensburg (Germany)

    2011-07-15

    Selective area growth of GaN nanorods by metalorganic vapor phase epitaxy is highly demanding for novel applications in nano-optoelectronic and nanophotonics. Recently, we report the successful selective area growth of GaN nanorods in a continuous-flow mode. In this work, as examples, we show the morphology dependence of GaN rods with {mu}m or sub-{mu}m in diameters on growth conditions. Firstly, we found that the nitridation time is critical for the growth, with an optimum from 90 to 180 seconds. This leads to more homogeneous N-polar GaN rods growth. A higher temperature during GaN rod growth tends to increase the aspect ratio of the GaN rods. This is due to the enhanced surface diffusion of growth species. The V/III ratio is also an important parameter for the GaN rod growth. Its increase causes reduction of the aspect ratio of GaN rods, which could be explained by the relatively lower growth rate on (000-1) N-polar top surface than it on {l_brace}1-100{r_brace} m-planes by supplying more NH{sub 3} (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Late sequelae of a non-optimal neonatal neurological condition in ERPs at the age of 11-13 years.

    Science.gov (United States)

    De Sonneville, L M; Visser, S L; Njiokiktjien, C

    1989-06-01

    In a longitudinal study a selective attention task was administered to 11-13-year-old children. During this task (employing a combined filter and selective-set paradigm), event-related brain potentials were recorded to study timing and morphology of early and late selection processes. Task performance was prospectively and retrospectively related to neurological optimality at birth and to flash-evoked potential correlates that were registered at the age of five. The results provided evidence that even after 13 years neonatal neurological suboptimality was reflected in task performance, both in reaction time and in electrophysiological data. Task load interacted with group classification according to optimality to the disadvantage of suboptimals. This implied that load demands differentiated between groups. The event-related brain potentials revealed the existence of a negative shift associated with memory load (search-related negativity) at Fz and Cz, and a positive deflection at Pz (P3b) associated with target detection. Cortical activity, expressed in terms of these deflections, appeared to be less pronounced for the suboptimal group.

  8. Growth of microbial mixed cultures under anaerobic, alkaline conditions

    International Nuclear Information System (INIS)

    Wenk, M.

    1993-09-01

    Cement and concrete are the most important engineered barrier materials in a repository for low- and intermediate-level waste and thus represent the most significant component of the total disposal inventory. Based on the chemical composition of the concrete used in the repository and the groundwater fluxes in the modelled host rock, it is to be expected that the pH in the near vicinity of the repository could exceed a value of 10.5 for more than a million years. The groundwater in the repository environment also has a limited carbon concentration. Since microorganisms will be present in a repository and can even find suitable living conditions within the waste itself, investigations were carried out in order to establish the extent to which microbial activity is possible under the extreme conditions of the repository near-field. For the investigations, alkalophilic cultures were enriched from samples from alkaline habitats and from Valanginian Marl. Anaerobic bacteria with fermentative, sulfate-reducing and methanogenic metabolism were selected. The growth and activity of the mixed cultures were studied under alkaline conditions and the dependence on pH and carbon concentration determined. All the mixed cultures investigated are alkalophilic. The optimum growth range for the cultures is between pH 9.0 and pH 10.0. The activity limit for the fermentative mixed culture is at pH 12, for the sulfate-reducers at pH 11 and for the methanogens at pH 10.5. Given the limited supply of carbon, the mixed cultures can only grow under slightly alkaline conditions. Only the fermentative cultures are capable of surviving with limited carbon supply at pH 13. (author) 24 figs., 18 tabs., 101 refs

  9. Simulation of fatigue crack growth under large scale yielding conditions

    Science.gov (United States)

    Schweizer, Christoph; Seifert, Thomas; Riedel, Hermann

    2010-07-01

    A simple mechanism based model for fatigue crack growth assumes a linear correlation between the cyclic crack-tip opening displacement (ΔCTOD) and the crack growth increment (da/dN). The objective of this work is to compare analytical estimates of ΔCTOD with results of numerical calculations under large scale yielding conditions and to verify the physical basis of the model by comparing the predicted and the measured evolution of the crack length in a 10%-chromium-steel. The material is described by a rate independent cyclic plasticity model with power-law hardening and Masing behavior. During the tension-going part of the cycle, nodes at the crack-tip are released such that the crack growth increment corresponds approximately to the crack-tip opening. The finite element analysis performed in ABAQUS is continued for so many cycles until a stabilized value of ΔCTOD is reached. The analytical model contains an interpolation formula for the J-integral, which is generalized to account for cyclic loading and crack closure. Both simulated and estimated ΔCTOD are reasonably consistent. The predicted crack length evolution is found to be in good agreement with the behavior of microcracks observed in a 10%-chromium steel.

  10. Individual specialization to non-optimal hosts in a polyphagous marine invertebrate herbivore.

    Directory of Open Access Journals (Sweden)

    Finn A Baumgartner

    Full Text Available Factors determining the degree of dietary generalism versus specialism are central in ecology. Species that are generalists at the population level may in fact be composed of specialized individuals. The optimal diet theory assumes that individuals choose diets that maximize fitness, and individual specialization may occur if individuals' ability to locate, recognize, and handle different food types differ. We investigate if individuals of the marine herbivorous slug Elysia viridis, which co-occur at different densities on several green macroalgal species in the field, are specialized to different algal hosts. Individual slugs were collected from three original algal host species (Cladophora sericea, Cladophora rupestris and Codium fragile in the field, and short-term habitat choice and consumption, as well as long-term growth (proxy for fitness, on four algal diet species (the original algal host species and Chaetomorpha melagonium were studied in laboratory experiments. Nutritional (protein, nitrogen, and carbon content and morphological (dry weight, and cell/utricle volume algal traits were also measured to investigate if they correlated with the growth value of the different algal diets. E. viridis individuals tended to choose and consume algal species that were similar to their original algal host. Long-term growth of E. viridis, however, was mostly independent of original algal host, as all individuals reached a larger size on the non-host C. melagonium. E. viridis growth was positively correlated to algal cell/utricle volume but not to any of the other measured algal traits. Because E. viridis feeds by piercing individual algal cells, the results indicate that slugs may receive more cytoplasm, and thus more energy per unit time, on algal species with large cells/utricles. We conclude that E. viridis individuals are specialized on different hosts, but host choice in natural E. viridis populations is not determined by the energetic value of

  11. Growth conditions determine the DNF2 requirement for symbiosis.

    Directory of Open Access Journals (Sweden)

    Fathi Berrabah

    Full Text Available Rhizobia and legumes are able to interact in a symbiotic way leading to the development of root nodules. Within nodules, rhizobia fix nitrogen for the benefit of the plant. These interactions are efficient because spectacularly high densities of nitrogen fixing rhizobia are maintained in the plant cells. DNF2, a Medicago truncatula gene has been described as required for nitrogen fixation, bacteroid's persistence and to prevent defense-like reactions in the nodules. This manuscript shows that a Rhizobium mutant unable to differentiate is not sufficient to trigger defense-like reactions in this organ. Furthermore, we show that the requirement of DNF2 for effective symbiosis can be overcome by permissive growth conditions. The dnf2 knockout mutants grown in vitro on agarose or Phytagel as gelling agents are able to produce nodules fixing nitrogen with the same efficiency as the wild-type. However, when agarose medium is supplemented with the plant defense elicitor ulvan, the dnf2 mutant recovers the fix- phenotype. Together, our data show that plant growth conditions impact the gene requirement for symbiotic nitrogen fixation and suggest that they influence the symbiotic suppression of defense reactions in nodules.

  12. Effects of growth conditions on thermal profiles during Czochralski silicon crystal growth

    Science.gov (United States)

    Choe, Kwang Su; Stefani, Jerry A.; Dettling, Theodore B.; Tien, John K.; Wallace, John P.

    1991-01-01

    An eddy current testing method was used to continuously monitor crystal growth process and investigate the effects of growth conditions on thermal profiles during Czochralski silicon crystal growth. The experimental concept was to monitor the intrinsic electrical conductivities of the growing crystal and deduce temperature values from them. In terms of the experiments, the effects of changes in growth parameters, which include the crystal and crucible rotation rates, crucible position, and pull rate, and hot-zone geometries were investigated. The results show that the crystal thermal profile could shift significantly as a function of crystal length if the closed-loop control fails to maintain a constant thermal condition. As a direct evidence to the effects of the melt flow on heat transfer processes, a thermal gradient minimum was observed when the crystal/crucible rotation combination was 20/-10 rpm cw. The thermal gradients in the crystal near the growth interface were reduced most by decreasing the pull rate or by reducing the radiant heat loss to the environment; a nearly constant axial thermal gradient was achieved when either the pull rate was decreased by half, the height of the exposed crucible wall was doubled, or a radiation shield was placed around the crystal. Under these conditions, the average axial thermal gradient along the surface of the crystal was about 4-5°C/mm. When compared to theoretical results found in literature, the axial profiles correlated well with the results of the models which included radiant interactions. However, the radial gradients estimated from three-frequency data were much higher than what were predicted by known theoretical models. This discrepancy seems to indicate that optical phenomenon within the crystal is significant and should be included in theoretical modeling.

  13. The onset condition of equatorial plasma bubbles - the role of seeding mechanism and growth condition

    Science.gov (United States)

    Kil, H.; Choi, J. M.; Kwak, Y. S.; Lee, W. K.; Park, J.

    2015-12-01

    We investigate the role of seeding mechanism and growth condition of perturbations in the creation of equatorial plasma bubbles by analyzing the C/NOFS and ROCSAT-1 satellite observations. The initial development times of bubbles were identified by manual processing of the data, and the periodic characteristics in the occurrence of bubbles were investigated using periodograms obtained from segments of bubble chains. Our preliminary results show that bubbles initiate at the time that the pre-reversal enhancement (PRE) ends. This time corresponds to the time that the F region reaches the highest altitude where the growth rate of the Rayleigh-Taylor (R-T) instability is large. The initial onset time of bubbles varies with season and longitude in accordance with the variation of the PRE ending time. Our investigation of the periodicity in the occurrence of bubbles (spacing between bubbles) shows that a dominant periodicity does not exist; the spacing between bubbles ranges from 100 km to over 1000 km. A pronounced periodicity occurs in some series of bubbles, but, in general, multiple periodicity co-exists. The initiation of bubbles at a specific local time but the absence of a preferential wave property in the occurrence of bubbles lead to the conclusion that the onset of bubbles is controlled by the growth condition of the R-T instability.

  14. Aging yeast gain a competitive advantage on non-optimal carbon sources.

    Science.gov (United States)

    Frenk, Stephen; Pizza, Grazia; Walker, Rachael V; Houseley, Jonathan

    2017-06-01

    Animals, plants and fungi undergo an aging process with remarkable physiological and molecular similarities, suggesting that aging has long been a fact of life for eukaryotes and one to which our unicellular ancestors were subject. Key biochemical pathways that impact longevity evolved prior to multicellularity, and the interactions between these pathways and the aging process therefore emerged in ancient single-celled eukaryotes. Nevertheless, we do not fully understand how aging impacts the fitness of unicellular organisms, and whether such cells gain a benefit from modulating rather than simply suppressing the aging process. We hypothesized that age-related loss of fitness in single-celled eukaryotes may be counterbalanced, partly or wholly, by a transition from a specialist to a generalist life-history strategy that enhances adaptability to other environments. We tested this hypothesis in budding yeast using competition assays and found that while young cells are more successful in glucose, highly aged cells outcompete young cells on other carbon sources such as galactose. This occurs because aged yeast divide faster than young cells in galactose, reversing the normal association between age and fitness. The impact of aging on single-celled organisms is therefore complex and may be regulated in ways that anticipate changing nutrient availability. We propose that pathways connecting nutrient availability with aging arose in unicellular eukaryotes to capitalize on age-linked diversity in growth strategy and that individual cells in higher eukaryotes may similarly diversify during aging to the detriment of the organism as a whole. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  15. Growth patterns for etiolated soybeans germinated under spaceflight conditions

    Science.gov (United States)

    Levine, Howard G.; Piastuch, William C.

    In the GENEX (GENe EXpression) spaceflight experiment (flown on STS-87), six surface sterilized soybean seeds ( Glycine max cv McCall) were inserted into each of 32 autoclaved plastic seed growth pouches containing an inner germination paper sleeve (for a total of 192 seeds). The pouches were stowed within a mid-deck locker until Mission Flight Day 10, at which time an astronaut added water to initiate the process of seed germination on-orbit and subsequently transferred them to four light-tight aluminum canisters called BRIC-60s (Biological Research In Canisters). We report here on the morphological characteristics of: (1) the recovered flight plants ( N = 177), (2) the corresponding ground control population ( N = 183), plus (3) additional controls grown on the ground under clinostat conditions ( N = 93). No significant morphological differences were found between the flight, ground control and clinorotated treatments for either the cotyledons or hypocotyls. There were, however, significantly longer primary roots produced in the flight population relative to the ground control population, which in turn had significantly longer primary roots than the clinorotated population. This same pattern was observed relative to the production of lateral roots (flight > control > clinorotated). Taken together with previous literature reports, we believe that there is now sufficient evidence to conclude that plants grown under conditions of microgravity will generally exhibit enhanced root production relative to their ground control counterparts. Some causes underlying this phenomenon are speculated on.

  16. Improving growth performance in calves under hot weather conditions

    International Nuclear Information System (INIS)

    Emara, S.S.M.

    2009-01-01

    The main objectives of the present study were to evaluate the effect of some supplement such as dried live yeast DLY (Saccharomyces cerevisiae), DLY + vitamin E and / or dried whey milk (DWM) on blood constituents and thyroid activity in relation to some immune indices and growth performance of calves under hot weather conditions. The ambient temperature and relative humidity averaged 36.9±4 degree C and 43-58 % during day and 29±4 degree C and 60-68 % during night, respectively, which were equivalent to temperature humidity index of 86-89 during day and 78-80 during night . The present study included three experiments as follows. Experiment 1 : Six female bovine Baladi calves of 8-10 months old and 100 kg initial body weight (IBW) were used during two periods. In the first period, the calves were offered the basal diet for one month and considered as a control period. In the second period, the same calves were fed the same basal diet which supplemented with 15 g / calf/ day DLY for one month and considered as treated period. The obtained results indicated that supplementation of DLY reduced significantly the respiration rate (RR) and rectal temperature (RT) as well as serum lipids profile including total cholesterol, low density lipoprotein (LDL- cholesterol) very low density lipoprotein (VLDL-cholesterol) triglycerides and phospholipids.The second and third experiments were carried out for improving growth performance of heat-stressed bovine baladi calves by adding DLY and vitamine E (alpha-tocopherol) to their diet in experiment 2 and dried whey milk (DWM) in experiment 3.

  17. Effect of cultivation conditions on growth and antifungal activity of ...

    African Journals Online (AJOL)

    Administrator

    Growth and production of antifungal agent by Mycena leptocephala was investigated in different culture media composition at various initial pH and temperatures. Maximum growth and activity was observed at the initial pH of 5.5 and 25oC. No detectable growth and activity was observed at pH of 3.5 and 7.5. Growth of the ...

  18. Stress-Related Growth in Two Challenging Conditions

    Czech Academy of Sciences Publication Activity Database

    Šolcová, Iva; Tavel, P.

    2017-01-01

    Roč. 13, č. 1 (2017), č. článku 4. ISSN 1529-5168 Institutional support: RVO:68081740 Keywords : Mars-500 * cruise * personal growth * spirituality, cognitive growth * social growth Subject RIV: AN - Psychology OBOR OECD: Psychology (including human - machine relations)

  19. Placental growth factor expression is reversed by antivascular endothelial growth factor therapy under hypoxic conditions.

    Science.gov (United States)

    Zhou, Ai-Yi; Bai, Yu-Jing; Zhao, Min; Yu, Wen-Zhen; Huang, Lv-Zhen; Li, Xiao-Xin

    2014-08-01

    Clinical trials have revealed that the antivascular endothelial growth factor (VEGF) therapies are effective in retinopathy of prematurity (ROP). But the low level of VEGF was necessary as a survival signal in healthy conditions, and endogenous placental growth factor (PIGF) is redundant for development. The purpose of this study was to elucidate the PIGF expression under hypoxia as well as the influence of anti-VEGF therapy on PIGF. CoCl2-induced hypoxic human umbilical vein endothelial cells (HUVECs) were used for an in vitro study, and oxygen-induced retinopathy (OIR) mice models were used for an in vivo study. The expression patterns of PIGF under hypoxic conditions and the influence of anti-VEGF therapy on PIGF were evaluated by quantitative reverse transcription-polymerase chain reaction (RTPCR). The retinal avascular areas and neovascularization (NV) areas of anti-VEGF, anti-PIGF and combination treatments were calculated. Retina PIGF concentration was evaluated by ELISA after treatment. The vasoactive effects of exogenous PIGF on HUVECs were investigated by proliferation and migration studies. PIGF mRNA expression was reduced by hypoxia in OIR mice, in HUVECs under hypoxia and anti-VEGF treatment. However, PIGF expression was reversed by anti-VEGF therapy in the OIR model and in HUVECs under hypoxia. Exogenous PIGF significantly inhibited HUVECs proliferation and migration under normal conditions, but it stimulated cell proliferation and migration under hypoxia. Anti-PIGF treatment was effective for neovascular tufts in OIR mice (P<0.05). The finding that PIGF expression is iatrogenically up-regulated by anti-VEGF therapy provides a consideration to combine it with anti-PIGF therapy.

  20. Peroxisomal catalase deficiency modulates yeast lifespan depending on growth conditions

    NARCIS (Netherlands)

    Kawalek, Adam; Lefevre, Sophie D.; Veenhuis, Marten; van der Klei, Ida J.

    We studied the role of peroxisomal catalase in chronological aging of the yeast Hansenula polymorpha in relation to various growth substrates. Catalase-deficient (cat) cells showed a similar chronological life span (CLS) relative to the wild-type control upon growth on carbon and nitrogen sources

  1. Glucose metabolism in Lactococcus lactis MG1363 under different aeration conditions: Requirement of acetate to sustain growth under microaerobic conditions

    DEFF Research Database (Denmark)

    Nordkvist, Mikkel; Jensen, N.B.S.; Villadsen, John

    2003-01-01

    Lactococcus lactis subsp. lactis MG1363 was grown in batch cultures on a defined medium with glucose as the energy source under different aeration conditions, namely, anaerobic conditions, aerobic conditions, and microaerobic conditions with a dissolved oxygen tension of 5% (when saturation...... resulted in acetate, CO2, and acetoin replacing formate and ethanol as end products. Under microaerobic conditions, growth came to a gradual halt, although more than 60% of the glucose was still left. A decline in growth was not observed during microaerobic cultivation when acetate was added to the medium...

  2. Optimal Conditions for the Mycelial Growth of Coprinus comatus Strains

    Science.gov (United States)

    Lee, Yun-Hae; Liu, Jun-Jie; Ju, Young-Cheol

    2009-01-01

    The principal objective of this study was to acquire basic data regarding the mycelial growth characteristics for the artificial cultivation of Coprinus comatus. 12 URP primers were employed to evaluate the genetic relationships of C. comatus, and the results were divided into three groups. Among six kinds of mushroom media, MYP medium was selected as the most favorable culture medium for C. comatus. The optimal temperature and pH ranges for the mycelial growth of C. comatus were 23~26℃ and pH 6~8, respectively. The carbon and nitrogen sources for optimal mycelial growth were sucrose and tryptone, respectively. PMID:23983517

  3. Influence of growth conditions on microstructure and defects in ...

    Indian Academy of Sciences (India)

    and dislocations in the intermediate Si layer are generated due to the development of non-uniform stresses during ... during the initial stages of growth on substrate and reporting ..... Research for financial support for carrying out the present.

  4. Growth Conditions Regulate the Requirements for Caulobacter Chromosome Segregation

    DEFF Research Database (Denmark)

    Shebelut, Conrad W.; Jensen, Rasmus Bugge; Gitai, Zemer

    2009-01-01

    Growth environments are important metabolic and developmental regulators. Here we demonstrate a growth environment-dependent effect on Caulobacter chromosome segregation of a small-molecule inhibitor of the MreB bacterial actin cytoskeleton. Our results also implicate ParAB as important segregation...... determinants, suggesting that multiple distinct mechanisms can mediate Caulobacter chromosome segregation and that their relative contributions can be environmentally regulated....

  5. Conditions for microbial growth in the FILTRA steam absorption tower

    International Nuclear Information System (INIS)

    Nilsson, H.; Roffey, R.

    1983-08-01

    By the appointment of the Southern Sweden Power Supply an experimental study has been carried out in order to evaluate the risk for microbial growth in the planned FILTRA steam absorbtion tower at the nuclear power plant in Barsebaeck. Four modelsystems were supplied with nitrogen atmosphere and a relative humidity of 100, 75, 50 and 25 percent. The fifth system received air and 75 percent relative humidity. Samples were collected and analysed for microbial growth after 1, 2, 4 and 8 months. The amounts of microorganisms and the ATP content was monitored. No measureable growth of any significance could be observed after 8 months in any system. An elementary analyses showed that the level of nitrogen and carbon in the stones was below the limit of detection (<0.3 percent C, <0.2 percent N). (author)

  6. Optimizing Growth Conditions for Digoxin Production in Digitalis lanata Ehrh

    Directory of Open Access Journals (Sweden)

    Herman A. van Wietmarschen

    2016-08-01

    Full Text Available Objective: Digoxin is a therapeutic cardenolide widely used to treat various heart conditions such as atrial flutter, atrial fibrillation and heart failure in both Western as well as Chinese medicine. Digoxin is extracted from cultivated Digitalis lanata Ehrh. plants, known as Mao Hua Yang Di Huang in Chinese medicine. This manuscript presents two studies that were conducted to optimize the cultivation conditions for digoxin production in the TCM Mao Hua Yan Di Huang in a greenhouse under GAP conditions.

  7. THE CONDITIONS OF TRANSITION TO INNOVATIVE TYPE OF ECONOMIC GROWTH

    OpenAIRE

    D. E. Sorokin

    2010-01-01

    Article is devoted theoretical-methodological problems of transition of the Russian economy to innovative type of economic growth. Realization of the problems set forth above are possible only in case of a support of the Russian economy on the fifth technological way and its abilities to pass to the sixth technological way.

  8. Growth of Sulphuric Acid Nanoparticles Under Wet and Dry Conditions

    Czech Academy of Sciences Publication Activity Database

    Škrabalová, Lenka; Brus, David; Antilla, T.; Ždímal, Vladimír; Lihavainen, H.

    2014-01-01

    Roč. 14, č. 12 (2014), s. 6461-6475 ISSN 1680-7316 R&D Projects: GA AV ČR IAA200760905 Grant - others:AFCEP(FI) 1118615 Institutional support: RVO:67985858 Keywords : binary nucleation * sulphuric acid - water * condensational growth Subject RIV: BJ - Thermodynamics Impact factor: 5.053, year: 2014

  9. Examining environmental condition on the growth areas of Turkish ...

    African Journals Online (AJOL)

    In this study, recent hazelnut growth areas were determined by Remote Sensing techniques for Trabzon province of Turkey. By using Geographical Information Systems (GIS) techniques, environmental data such as elevation, slope, aspect, geology, and soil data were produced and analyzed to examine environmental ...

  10. Analysis of gene essentiality in Escherichia coli across strains and growth conditions

    DEFF Research Database (Denmark)

    Bonde, Ida; Lennen, Rebecca; Cardoso, Joao

    are either essential or detrimental for growth in the test condition in question. In this study the TN-Seq method was used to investigate the differences in gene essentiality between four laboratory strains of E.coli subjected to four different growth conditions to investigate the reason for the differences...

  11. The list of strains and growth conditions - The Rice Growth Monitoring for The Phenotypic Functional Analysis | LSDB Archive [Life Science Database Archive metadata

    Lifescience Database Archive (English)

    Full Text Available List Contact us The Rice Growth Monitoring for The Phenotypic Functional Analysis The list of strains and growth... conditions Data detail Data name The list of strains and growth conditions DOI 10.18908/lsdba.nbdc00945...-001 Description of data contents The list of strains and growth conditions for respective samples. Data fil...servation Intervals of imaging Intervals of imaging Growth data Graph of chronological changes in growth Ima...History of This Database Site Policy | Contact Us The list of strains and growth conditions - The Rice Growth Monitoring for The Phenotypic Functional Analysis | LSDB Archive ...

  12. Vision-based judgment of tomato maturity under growth conditions ...

    African Journals Online (AJOL)

    To determine the picking time of tomato and design the control strategy for the harvesting robot, the judgment of tomato maturity under natural conditions is ... Hue-mean and red-green color-difference image mean can be used as a criterion for the judgment of tomato maturity, and the tests indicated that the redgreen mean ...

  13. Performing Comparative Peptidomics Analyses of Salmonella from Different Growth Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Adkins, Joshua N.; Mottaz, Heather; Metz, Thomas O.; Ansong, Charles K.; Manes, Nathan P.; Smith, Richard D.; Heffron, Fred

    2010-01-08

    Host–pathogen interactions are complex competitions during which both the host and the pathogen adapt rapidly to each other in order for one or the other to survive. Salmonella enterica serovar Typhimurium is a pathogen with a broad host range that causes a typhoid fever-like disease in mice and severe food poisoning in humans. The murine typhoid fever is a systemic infection in which S.typhimurium evades part of the immune system by replicating inside macrophages and other cells. The transition from a foodborne contaminant to an intracellular pathogen must occur rapidly in multiple,ordered steps in order for S. typhimurium to thrive within its host environment. Using S. typhimurium isolated from rich culture conditions and from conditions that mimic the hostile intracellular environment of the host cell, a native low molecular weight protein fraction, or peptidome, was enriched from cell lysates by precipitation with organic solvents. The enriched peptidome was analyzed by both LC–MS/MS and LC–MS-based methods, although several other methods are possible. Pre-fractionation of peptides allowed identification of small proteins and protein degradation products that would normally be overlooked. Comparison of peptides present in lysates prepared from Salmonella grown under different conditions provided a unique insight into cellular degradation processes as well as identification of novel peptides encoded in the genome but not annotated. The overall approach is detailed here as applied to Salmonella and is adaptable to a broad range of biological systems.

  14. Growth curves and the international standard: How children's growth reflects challenging conditions in rural Timor-Leste.

    Science.gov (United States)

    Spencer, Phoebe R; Sanders, Katherine A; Judge, Debra S

    2018-02-01

    Population-specific growth references are important in understanding local growth variation, especially in developing countries where child growth is poor and the need for effective health interventions is high. In this article, we use mixed longitudinal data to calculate the first growth curves for rural East Timorese children to identify where, during development, deviation from the international standards occurs. Over an eight-year period, 1,245 children from two ecologically distinct rural areas of Timor-Leste were measured a total of 4,904 times. We compared growth to the World Health Organization (WHO) standards using z-scores, and modeled height and weight velocity using the SuperImposition by Translation And Rotation (SITAR) method. Using the Generalized Additive Model for Location, Scale and Shape (GAMLSS) method, we created the first growth curves for rural Timorese children for height, weight and body mass index (BMI). Relative to the WHO standards, children show early-life growth faltering, and stunting throughout childhood and adolescence. The median height and weight for this population tracks below the WHO fifth centile. Males have poorer growth than females in both z-BMI (p = .001) and z-height-for-age (p = .018) and, unlike females, continue to grow into adulthood. This is the most comprehensive investigation to date of rural Timorese children's growth, and the growth curves created may potentially be used to identify future secular trends in growth as the country develops. We show significant deviation from the international standard that becomes most pronounced at adolescence, similar to the growth of other Asian populations. Males and females show different growth responses to challenging conditions in this population. © 2017 Wiley Periodicals, Inc.

  15. Media and growth conditions for induction of secondary metabolite production

    DEFF Research Database (Denmark)

    Frisvad, Jens Christian

    2012-01-01

    -defined media are suited for biochemical studies, but in order to get chemical diversity expressed in filamentous fungi, sources rich in amino acids, vitamins, and trace metals have to be added, such as yeast extract and oatmeal. A battery of solid agar media is recommended for exploration of chemical diversity...... as agar plug samples are easily analyzed to get an optimal representation of the qualitative secondary metabolome. Standard incubation for a week at 25°C in darkness is recommended, but optimal conditions have to be modified depending on the ecology and physiology of different filamentous fungi....

  16. Crack growth threshold under hold time conditions in DA Inconel 718 – A transition in the crack growth mechanism

    Directory of Open Access Journals (Sweden)

    E. Fessler

    2016-01-01

    Full Text Available Aeroengine manufacturers have to demonstrate that critical components such as turbine disks, made of DA Inconel 718, meet the certification requirements in term of fatigue crack growth. In order to be more representative of the in service loading conditions, crack growth under hold time conditions is studied. Modelling crack growth under these conditions is challenging due to the combined effect of fatigue, creep and environment. Under these conditions, established models are often conservative but the degree of conservatism can be reduced by introducing the crack growth threshold in models. Here, the emphasis is laid on the characterization of crack growth rates in the low ΔK regime under hold time conditions and in particular, on the involved crack growth mechanism. Crack growth tests were carried out at high temperature (550 °C to 650 °C under hold time conditions (up to 1200 s in the low ΔK regime using a K-decreasing procedure. Scanning electron microscopy was used to identify the fracture mode involved in the low ΔK regime. EBSD analyses and BSE imaging were also carried out along the crack path for a more accurate identification of the fracture mode. A transition from intergranular to transgranular fracture was evidenced in the low ΔK regime and slip bands have also been observed at the tip of an arrested crack at low ΔK. Transgranular fracture and slip bands are usually observed under pure fatigue loading conditions. At low ΔK, hold time cycles are believed to act as equivalent pure fatigue cycles. This change in the crack growth mechanism under hold time conditions at low ΔK is discussed regarding results related to intergranular crack tip oxidation and its effect on the crack growth behaviour of Inconel 718 alloy. A concept based on an “effective oxygen partial pressure” at the crack tip is proposed to explain the transition from transgranular to intergranular fracture in the low ΔK regime.

  17. Effects of plant–soil feedback on tree seedling growth under arid conditions

    NARCIS (Netherlands)

    Meijer, S.S.; Holmgren, M.; Van der Putten, W.H.

    2011-01-01

    Aims Plants are able to influence their growing environment by changing biotic and abiotic soil conditions. These soil conditions in turn can influence plant growth conditions, which is called plant–soil feedback. Plant–soil feedback is known to be operative in a wide variety of ecosystems ranging

  18. Effects of plant-soil feedback on tree seedling growth under arid conditions

    NARCIS (Netherlands)

    Meijer, S.S.; Holmgren, M.; Putten, van der W.H.

    2011-01-01

    Aims: Plants are able to influence their growing environment by changing biotic and abiotic soil conditions. These soil conditions in turn can influence plant growth conditions, which is called plant–soil feedback. Plant–soil feedback is known to be operative in a wide variety of ecosystems ranging

  19. Priority target conditions for algorithms for monitoring children's growth: Interdisciplinary consensus.

    Directory of Open Access Journals (Sweden)

    Pauline Scherdel

    Full Text Available Growth monitoring of apparently healthy children aims at early detection of serious conditions through the use of both clinical expertise and algorithms that define abnormal growth. Optimization of growth monitoring requires standardization of the definition of abnormal growth, and the selection of the priority target conditions is a prerequisite of such standardization.To obtain a consensus about the priority target conditions for algorithms monitoring children's growth.We applied a formal consensus method with a modified version of the RAND/UCLA method, based on three phases (preparatory, literature review, and rating, with the participation of expert advisory groups from the relevant professional medical societies (ranging from primary care providers to hospital subspecialists as well as parent associations. We asked experts in the pilot (n = 11, reading (n = 8 and rating (n = 60 groups to complete the list of diagnostic classification of the European Society for Paediatric Endocrinology and then to select the conditions meeting the four predefined criteria of an ideal type of priority target condition.Strong agreement was obtained for the 8 conditions selected by the experts among the 133 possible: celiac disease, Crohn disease, craniopharyngioma, juvenile nephronophthisis, Turner syndrome, growth hormone deficiency with pituitary stalk interruption syndrome, infantile cystinosis, and hypothalamic-optochiasmatic astrocytoma (in decreasing order of agreement.This national consensus can be used to evaluate the algorithms currently suggested for growth monitoring. The method used for this national consensus could be re-used to obtain an international consensus.

  20. Photophysiological variability of microphytobenthic diatoms after growth in different types of culture conditions

    NARCIS (Netherlands)

    Forster, R.M.; Martin-Jézéquel, V.R.

    2005-01-01

    Microphytobenthic diatoms have great ecological importance in estuarine and coastal marine ecosystenis, yet many aspects of their physiology have not been investigated under controlled conditions. This work describes patterns in growth rates and photosynthesis in different types of culture for

  1. Bacillus spp. from rainforest soil promote plant growth under limited nitrogen conditions.

    Science.gov (United States)

    Huang, X-F; Zhou, D; Guo, J; Manter, D K; Reardon, K F; Vivanco, J M

    2015-03-01

    The aim of this study was to evaluate effects of PGPR (plant growth-promoting rhizobacteria) isolated from rainforest soil on different plants under limited nitrogen conditions. Bacterial isolates from a Peruvian rainforest soil were screened for plant growth-promoting effects on Arabidopsis (Col-0). Four selected isolates including one Bacillus subtilis, two B. atrophaeus and one B. pumilus significantly promoted growth of Zea mays L. and Solanum lycopersicum under greenhouse conditions. Moreover, the PGPRs significantly promoted growth of S. lycopersicum in both low and nitrogen-amended soil conditions. These PGPR strains were further studied to obtain insights into possible mechanisms of plant growth promotion. Volatile chemicals from those isolates promoted Arabidopsis growth, and the expression of genes related to IAA production was induced in the Arabidopsis plants treated with PGPRs. Further, selected PGPR strains triggered induced systemic resistance (ISR) against Pseudomonas syringae pv tomato DC3000 in Arabidopsis. PGPR strains isolated from the rainforest soil promoted the plant growth of Arabidopsis, corn and tomato. New PGPR that have wider adaptability to different crops, soils and environmental conditions are needed to decrease our reliance on agricultural amendments derived from fossil-based fuels. The PGPRs isolated from a nonagricultural site constitute new plant growth-promoting strains that could be developed for agricultural uses. © 2014 The Society for Applied Microbiology.

  2. An endogenous Taylor condition in an endogenous growth monetary policy model

    OpenAIRE

    Le, Mai Vo; Gillman, Max; Minford, Patrick

    2007-01-01

    The paper derives a Taylor condition as part of the agent's equilibrium behavior in an endogenous growth monetary economy. It shows the assumptions necessary to make it almost identical to the original Taylor rule, and that it can interchangably take a money supply growth rate form. From the money supply form, simple policy experiments are conducted. A full central bank policy model is derived that includes the Taylor condition along with equations comparable to the standard aggregate-demand/...

  3. Diatom production in the marine environment : implications for larval fish growth and condition

    DEFF Research Database (Denmark)

    St. John, Michael; Clemmesen, C.; Lund, T.

    2001-01-01

    To test the effects of diatom production on larval fish growth and condition. laboratory experiments were performed with larval North Sea cod reared on different algal food chains. These food chains were based on cultures of (a) the diatoms Skeletonema costatum and Thalassiosira weissflogii: (b....../omega6 fatty acids in the algal source had no significant effect. The highest and lowest growth rates were observed in food chains based on H. triquetra and T. weissflogii. respectively (means for days 14-16 of 4.0 and - 4.7). The mixed diatom/dinoflagellate diet resulted in inter- mediate growth rates...... and condition. Regressions of growth rates against EPA and DHA content indicated no inhibitory effect of diatom production on growth in larval cod...

  4. Crack growth under combined creep and fatigue conditions in alloy 800

    International Nuclear Information System (INIS)

    Pfaffelhuber, M.; Roedig, M.; Schubert, F.; Nickel, H.

    1989-08-01

    To investigate the crack growth behaviour under combined creep-fatigue loading, CT 25 mm-specimens of X10NiCrAlTi 32 20 (Alloy 800) have been tested in experiments with cyclic loadings and hold times, with static loadings and short stress rekief interrupts, with ramp type loadings and with sequences of separate fatigue and creep crack growth periods. The test temperature of 700deg C was selected because only in this temperature range this alloy provides similar amounts of crack growth under creep and fatigue conditions due to equivalent stress levels. For the estimation of crack growth under combined loading conditions a linear accumulation of increase in crack length was proved using the crack growth laws of pure creep and fatigue crack growth. Hold time and ramp loadings lead to a higher crack growth rate compared with pure creep or pure fatigue crack growth tests. In hold time experiments the crack growth rate is higher than ramp tests of the same period time. The results of hold time tests can be fairly enough predicted by linear damage accumulation rules. (orig.) [de

  5. Growth of AlGaN under the conditions of significant gallium evaporation: phase separation and enhanced lateral growth

    OpenAIRE

    Mayboroda, I. O.; Knizhnik, A. A.; Grishchenko, Yu. V.; Ezubchenko, I. S.; Zanaveskin, Maxim L.; Presniakov, M. Yu.; Potapkin, B. V.; Ilyin, V. A.

    2017-01-01

    Growth kinetics of AlGaN in NH3 MBE under significant Ga desorption was studied. It was found that the addition of gallium stimulates 2D growth and provides better morphology of films compared to pure AlN. The effect was experimentally observed at up to 98% desorption of the impinging gallium. We found that, under the conditions of significant thermal desorption, larger amounts of gallium were retained at lateral boundaries of 3D surface features than at flat terraces because of the higher bi...

  6. Lettuce and rhizosphere microbiome responses to growth promoting Pseudomonas species under field conditions.

    Science.gov (United States)

    Cipriano, Matheus A P; Lupatini, Manoeli; Lopes-Santos, Lucilene; da Silva, Márcio J; Roesch, Luiz F W; Destéfano, Suzete A L; Freitas, Sueli S; Kuramae, Eiko E

    2016-12-01

    Plant growth promoting rhizobacteria are well described and recommended for several crops worldwide. However, one of the most common problems in research into them is the difficulty in obtaining reproducible results. Furthermore, few studies have evaluated plant growth promotion and soil microbial community composition resulting from bacterial inoculation under field conditions. Here we evaluated the effect of 54 Pseudomonas strains on lettuce (Lactuca sativa) growth. The 12 most promising strains were phylogenetically and physiologically characterized for plant growth-promoting traits, including phosphate solubilization, hormone production and antagonism to pathogen compounds, and their effect on plant growth under farm field conditions. Additionally, the impact of beneficial strains on the rhizospheric bacterial community was evaluated for inoculated plants. The strains IAC-RBcr4 and IAC-RBru1, with different plant growth promoting traits, improved lettuce plant biomass yields up to 30%. These two strains also impacted rhizosphere bacterial groups including Isosphaera and Pirellula (phylum Planctomycetes) and Acidothermus, Pseudolabrys and Singusphaera (phylum Actinobacteria). This is the first study to demonstrate consistent results for the effects of Pseudomonas strains on lettuce growth promotion for seedlings and plants grown under tropical field conditions. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. The effect of growth conditions on flavonols and anthocyanins accumulation in green and red lettuce

    OpenAIRE

    Klaudia BRÜCKOVÁ; Oksana SYTAR; Marek ŢIVČÁK; Marian BRESTIC; Aleš LEBEDA

    2016-01-01

    The aim of the study was to investigate the effect of different growth conditions on anthocyanins and flavonols accumulation in leaves of green and red loose leaf lettuce (Lactuca sativa var. crispa). Lettuce plants were grown in three types of conditions, in greenhouse (I. variant), behind clear glass in field (II. variant) and in open field conditions (III. variant). Estimation of anthocyanins and flavonols content was done by non-destructive measurements with optical fluorescence sensor Mu...

  8. Conditional random slope: A new approach for estimating individual child growth velocity in epidemiological research.

    Science.gov (United States)

    Leung, Michael; Bassani, Diego G; Racine-Poon, Amy; Goldenberg, Anna; Ali, Syed Asad; Kang, Gagandeep; Premkumar, Prasanna S; Roth, Daniel E

    2017-09-10

    Conditioning child growth measures on baseline accounts for regression to the mean (RTM). Here, we present the "conditional random slope" (CRS) model, based on a linear-mixed effects model that incorporates a baseline-time interaction term that can accommodate multiple data points for a child while also directly accounting for RTM. In two birth cohorts, we applied five approaches to estimate child growth velocities from 0 to 12 months to assess the effect of increasing data density (number of measures per child) on the magnitude of RTM of unconditional estimates, and the correlation and concordance between the CRS and four alternative metrics. Further, we demonstrated the differential effect of the choice of velocity metric on the magnitude of the association between infant growth and stunting at 2 years. RTM was minimally attenuated by increasing data density for unconditional growth modeling approaches. CRS and classical conditional models gave nearly identical estimates with two measures per child. Compared to the CRS estimates, unconditional metrics had moderate correlation (r = 0.65-0.91), but poor agreement in the classification of infants with relatively slow growth (kappa = 0.38-0.78). Estimates of the velocity-stunting association were the same for CRS and classical conditional models but differed substantially between conditional versus unconditional metrics. The CRS can leverage the flexibility of linear mixed models while addressing RTM in longitudinal analyses. © 2017 The Authors American Journal of Human Biology Published by Wiley Periodicals, Inc.

  9. Facet-Dependent Oxidative Goethite Growth As a Function of Aqueous Solution Conditions.

    Science.gov (United States)

    Strehlau, Jennifer H; Stemig, Melissa S; Penn, R Lee; Arnold, William A

    2016-10-04

    Nitroaromatic compounds are groundwater pollutants that can be degraded through reactions with Fe(II) adsorbed on iron oxide nanoparticles, although little is known about the evolving reactivity of the minerals with continuous pollutant exposure. In this work, Fe(II)/goethite reactivity toward 4-chloronitrobenzene (4-ClNB) as a function of pH, organic matter presence, and reactant concentrations was explored using sequential-spike batch reactors. Reaction rate constants were smaller with lower pH, introduction of organic matter, and diluted reactant concentrations as compared to a reference condition. Reaction rate constants did not change with the number of 4-ClNB spikes for all reaction conditions. Under all conditions, oxidative goethite growth was demonstrated through X-ray diffraction, magnetic characterization, and transmission electron microscopy. Nonparametric statistics were applied to compare histograms of lengths and widths of goethite nanoparticles as a function of varied solution conditions. The conditions that slowed the reaction also resulted in statistically shorter and wider particles than for the faster reactions. Additionally, added organic matter interfered with particle growth on the favorable {021} faces to a greater extent, with statistically reduced rate of growth on the tip facets and increased rate of growth on the side facets. These data demonstrate that oxidative growth of goethite in aqueous systems is dependent on major groundwater variables, such as pH and the presence of organic matter, which could lead to the evolving reactivity of goethite particles in natural environments.

  10. Cardiovascular disease mortality and years of life lost attributable to non-optimal systolic blood pressure and hypertension in northeastern Iran.

    Science.gov (United States)

    Sepanlou, Sadaf G; Newson, Roger B; Poustchi, Hossein; Malekzadeh, Masoud M; Rezanejad Asl, Parisa; Etemadi, Arash; Khademi, Hooman; Islami, Farhad; Pourshams, Akram; Pharoah, Paul D; Abnet, Christian C; Brennan, Paul; Bofetta, Paolo; Dawsey, Sanford M; Kamangar, Farin; Malekzadeh, Reza

    2015-03-01

    High blood pressure is the second most important risk factor of cardiovascular diseases (CVDs) in Iran. It is imperative to estimate the burden of CVDs that can be averted if high blood pressure is controlled at the population level. The aim of the current study was to estimate the avertable CVD mortality in the setting of Golestan Cohort Study (GCS). Over 50,000 participants were recruited and followed for a median of 7 years. The exposures of interest in this study were non-optimal systolic blood pressure (SBP) and hypertension measured at baseline. Deaths by cause have been precisely recorded. The Population Attributable Fraction (PAF) of deaths and Years of Life Lost (YLLs) due to CVDs attributable to exposures of interest were calculated. Overall, 223 deaths due to ischemic heart disease (IHD), 207 deaths due to cerebrovascular accidents (CVA), and 460 deaths due to all CVDs could be averted if the SBP of all subjects in the study were optimal. Similarly, 5,560 YLLs due to IHD, 4,771 YLLs due to CVA, and 11,135 YLLs due to CVDs could be prevented if SBP were optimal. In all age groups, the avertable deaths and YLLs were higher due to IHD compared with CVA. Deaths and YLLs attributable to non-optimal SBP in women were less than men. A very large proportion of CVD deaths can be averted if blood pressure is controlled in Iran. Effective interventions in primary and secondary health care setting are mandatory to be implemented as early as possible.

  11. On the conditions required for vacancy loop growth in irradiated metals and alloys

    International Nuclear Information System (INIS)

    Hayns, M.R.

    1980-07-01

    A simple theoretical model is investigated which allows the conditions under which vacancy dislocation loop growth is possible to be examined. This forms an extension of previous work in that bulk defect recombination is not ignored and the effects of vacancy thermal emission are included. Whilst the present work does not provide a kinetic model for vacancy loop growth it has been possible to examine the criteria required for stable growth in some detail. The effects of network dislocation density, temperature, damage rate, the influence of other critical sinks, notably voids and grain boundaries, and interstitial dislocation loops have been considered. The analogy with the growth conditions for cavities as voids is highlighted. A detailed comparison with experiment is not attempted as this is being considered separately. (author)

  12. The in vitro fitness cost of antimicrobial resistance in Escherichia coli varies with the growth conditions

    DEFF Research Database (Denmark)

    Petersen, Andreas; Aarestrup, Frank Møller; Olsen, John Elmerdahl

    2009-01-01

    The objective of this study was to investigate the influence of stressful growth conditions on the fitness cost of antimicrobial resistance in Escherichia coli BJ4 caused by chromosomal mutations and plasmid acquisition. The fitness cost of chromosomal streptomycin resistance increased......H and at high-salt concentrations. Strains with an impaired rpoS demonstrated a reduced fitness only during growth in a high-salt concentration. In conclusion, it was demonstrated that bacterial fitness cost in association with antimicrobial resistance generally increases under stressful growth conditions....... However, the growth potential of bacteria with antimicrobial resistances did not increase in a straightforward manner in these in vitro experiments and is therefore probably even more difficult to predict in vivo....

  13. Evaluation procedure of creep-fatigue defect growth in high temperature condition and application

    International Nuclear Information System (INIS)

    Park, Chang Gyu; Kim, Jong Bum; Lee, Jae Han

    2003-12-01

    This study proposed the evaluation procedure of creep-fatigue defect growth on the high-temperature cylindrical structure applicable to the KALIMER, which is developed by KAERI. Parameters used in creep defect growth and the evaluation codes with these parameters were analyzed. In UK, the evaluation procedure of defect initiation and growth were proposed with R5/R6 code. In Japan, simple evauation method was proposed by JNC. In France, RCC-MR A16 code which was evaluation procedure of the creep-fatigue defect initiation and growth related to leak before break was developed, and equations related to load conditions were modified lately. As an application example, the creep-fatigue defect growth on circumferential semi-elliptical surface defect in high temperature cylindrical structure was evaluated by RCC-MR A16

  14. Bulk water phase and biofilm growth in drinking water at low nutrient conditions

    DEFF Research Database (Denmark)

    Boe-Hansen, Rasmus; Albrechtsen, Hans-Jørgen; Arvin, Erik

    2002-01-01

    , and cell-specific leucine incorporation rate. Bacteria in the bulk water phase incubated without the presence of biofilmexhibited a bacterial growth rate of 0.30 day1. The biofilmwas radioactively labelled by the addition of 14C-benzoic acid. Subsequently, a biofilmdetachm ent rate of 0.013 day1...... the formation of a mature quasi-stationary biofilm. At retention times of 12 h, total bacterial counts increased equivalent to a net bacterial growth rate of 0.048 day1. The bulk water phase bacteria exhibited a higher activity than the biofilmbacteria in terms of culturability, cell-specific ATP content......In this study, the bacterial growth dynamics of a drinking water distribution system at low nutrient conditions was studied in order to determine bacterial growth rates by a range of methods, and to compare growth rates in the bulk water phase and the biofilm. A model distribution system was used...

  15. Effect of growth conditions on the photovoltaic efficiency of poly(terthiophene) based photoelectrochemical cells

    International Nuclear Information System (INIS)

    Tsekouras, George; Too, Chee O.; Wallace, Gordon G.

    2005-01-01

    Conditions associated with the electrochemical growth of poly(terthiophene) (PTTh) were shown to have a considerable effect on photovoltaic (PV) performance indicators, namely, short-circuit-current (I sc ), open-circuit-voltage (V oc ), fill-factor (FF) and power-conversion-efficiency (PCE). The solvent and electrochemical technique used during growth were found to have an effect on PV performance. Increasing the upper potential limit associated with growth by cyclic voltammetry (CV) was found to decrease PV efficiency. The use of higher temperatures during growth was found to improve PV performance. Conditions associated with the electrochemical growth of PTTh were found to affect PV performance because of resultant changes to the polymer morphology. Such changes were characterised using scanning electron microscopy (SEM). In general, PTTh morphologies that exhibited increased porosity gave better PV performance by increasing the contact area between the PTTh and the liquid electrolyte. Combining the optimum conditions for the electrochemical growth of PTTh yielded a photoelectrochemical cell (PEC) showing I sc = 888 μA cm -2 , V oc 152 mV, FF = 37.3% and PCE = 0.101% under halogen light (solar simulated) intensity of 500 W m -2

  16. A novel strategy to identify the critical conditions for growth-induced instabilities.

    Science.gov (United States)

    Javili, A; Steinmann, P; Kuhl, E

    2014-01-01

    Geometric instabilities in living structures can be critical for healthy biological function, and abnormal buckling, folding, or wrinkling patterns are often important indicators of disease. Mathematical models typically attribute these instabilities to differential growth, and characterize them using the concept of fictitious configurations. This kinematic approach toward growth-induced instabilities is based on the multiplicative decomposition of the total deformation gradient into a reversible elastic part and an irreversible growth part. While this generic concept is generally accepted and well established today, the critical conditions for the formation of growth-induced instabilities remain elusive and poorly understood. Here we propose a novel strategy for the stability analysis of growing structures motivated by the idea of replacing growth by prestress. Conceptually speaking, we kinematically map the stress-free grown configuration onto a prestressed initial configuration. This allows us to adopt a classical infinitesimal stability analysis to identify critical material parameter ranges beyond which growth-induced instabilities may occur. We illustrate the proposed concept by a series of numerical examples using the finite element method. Understanding the critical conditions for growth-induced instabilities may have immediate applications in plastic and reconstructive surgery, asthma, obstructive sleep apnoea, and brain development. © 2013 Elsevier Ltd. All rights reserved.

  17. Cholera toxin expression by El Tor Vibrio cholerae in shallow culture growth conditions.

    Science.gov (United States)

    Cobaxin, Mayra; Martínez, Haydee; Ayala, Guadalupe; Holmgren, Jan; Sjöling, Asa; Sánchez, Joaquín

    2014-01-01

    Vibrio cholerae O1 classical, El Tor and O139 are the primary biotypes that cause epidemic cholera, and they also express cholera toxin (CT). Although classical V. cholerae produces CT in various settings, the El Tor and O139 strains require specific growth conditions for CT induction, such as the so-called AKI conditions, which consist of growth in static conditions followed by growth under aerobic shaking conditions. However, our group has demonstrated that CT production may also take place in shallow static cultures. How these type of cultures induce CT production has been unclear, but we now report that in shallow culture growth conditions, there is virtual depletion of dissolved oxygen after 2.5 h of growth. Concurrently, during the first three to 4 h, endogenous CO2 accumulates in the media and the pH decreases. These findings may explain CT expression at the molecular level because CT production relies on a regulatory cascade, in which the key regulator AphB may be activated by anaerobiosis and by low pH. AphB activation stimulates TcpP synthesis, which induces ToxT production, and ToxT directly stimulates ctxAB expression, which encodes CT. Importantly, ToxT activity is enhanced by bicarbonate. Therefore, we suggest that in shallow cultures, AphB is activated by initial decreases in oxygen and pH, and subsequently, ToxT is activated by intracellular bicarbonate that has been generated from endogenous CO2. This working model would explain CT production in shallow cultures and, possibly, also in other growth conditions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Environmental Growth Conditions of Trichoderma spp. Affects Indole Acetic Acid Derivatives, Volatile Organic Compounds, and Plant Growth Promotion

    Science.gov (United States)

    Nieto-Jacobo, Maria F.; Steyaert, Johanna M.; Salazar-Badillo, Fatima B.; Nguyen, Dianne Vi; Rostás, Michael; Braithwaite, Mark; De Souza, Jorge T.; Jimenez-Bremont, Juan F.; Ohkura, Mana; Stewart, Alison

    2017-01-01

    Trichoderma species are soil-borne filamentous fungi widely utilized for their many plant health benefits, such as conferring improved growth, disease resistance and abiotic stress tolerance to their hosts. Many Trichoderma species are able to produce the auxin phytohormone indole-3-acetic acid (IAA), and its production has been suggested to promote root growth. Here we show that the production of IAA is strain dependent and diverse external stimuli are associated with its production. In in vitro assays, Arabidopsis primary root length was negatively affected by the interaction with some Trichoderma strains. In soil experiments, a continuum effect on plant growth was shown and this was also strain dependent. In plate assays, some strains of Trichoderma spp. inhibited the expression of the auxin reporter gene DR5 in Arabidopsis primary roots but not secondary roots. When Trichoderma spp. and A. thaliana were physically separated, enhancement of both shoot and root biomass, increased root production and chlorophyll content were observed, which strongly suggested that volatile production by the fungus influenced the parameters analyzed. Trichoderma strains T. virens Gv29.8, T. atroviride IMI206040, T. sp. “atroviride B” LU132, and T. asperellum LU1370 were demonstrated to promote plant growth through volatile production. However, contrasting differences were observed with LU1370 which had a negative effect on plant growth in soil but a positive effect in plate assays. Altogether our results suggest that the mechanisms and molecules involved in plant growth promotion by Trichoderma spp. are multivariable and are affected by the environmental conditions. PMID:28232840

  19. Monitoring growth condition of spring maize in Northeast China using a process-based model

    Science.gov (United States)

    Wang, Peijuan; Zhou, Yuyu; Huo, Zhiguo; Han, Lijuan; Qiu, Jianxiu; Tan, Yanjng; Liu, Dan

    2018-04-01

    Early and accurate assessment of the growth condition of spring maize, a major crop in China, is important for the national food security. This study used a process-based Remote-Sensing-Photosynthesis-Yield Estimation for Crops (RS-P-YEC) model, driven by satellite-derived leaf area index and ground-based meteorological observations, to simulate net primary productivity (NPP) of spring maize in Northeast China from the first ten-day (FTD) of May to the second ten-day (STD) of August during 2001-2014. The growth condition of spring maize in 2014 in Northeast China was monitored and evaluated spatially and temporally by comparison with 5- and 13-year averages, as well as 2009 and 2013. Results showed that NPP simulated by the RS-P-YEC model, with consideration of multi-scattered radiation inside the crop canopy, could reveal the growth condition of spring maize more reasonably than the Boreal Ecosystem Productivity Simulator. Moreover, NPP outperformed other commonly used vegetation indices (e.g., Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI)) for monitoring and evaluating the growth condition of spring maize. Compared with the 5- and 13-year averages, the growth condition of spring maize in 2014 was worse before the STD of June and after the FTD of August, and it was better from the third ten-day (TTD) of June to the TTD of July across Northeast China. Spatially, regions with slightly worse and worse growth conditions in the STD of August 2014 were concentrated mainly in central Northeast China, and they accounted for about half of the production area of spring maize in Northeast China. This study confirms that NPP is a good indicator for monitoring and evaluating growth condition because of its capacity to reflect the physiological characteristics of crops. Meanwhile, the RS-P-YEC model, driven by remote sensing and ground-based meteorological data, is effective for monitoring crop growth condition over large areas in a near real

  20. Growth dynamics variation of different larch provenances under the mountain conditions in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Kulej, M. [Univ. of Agriculture, Cracow (Poland). Section of Seed Production and Selection

    1995-12-31

    The results of 25-year investigations based on measurements and statistical analysis concerning the growth dynamics variation of larch provenances from the entire area of Poland are reported in this paper. This is the first larch provenance experiment in Poland under mountain conditions. The results obtained showed a significant variability among the provenances tested as regards the basic growth characters (height, d.b.h., growth index) at the age of 5, 8, 11, 15, 20 and 25 years. The larch from Klodzko and Proszkow turned out to be the best in respect of growth during the entire 25-years period. Decidedly bad were provenances from Marcule, Grojec, Rawa mazowiecka and Kroscienko. We cannot forecast the future growth of larch when trees are 5-years old since such prognosis may carry an error. However, on the basis of the results obtained it may be concluded that when trees are about 8 years old the stabilization of the position of individual provenances as regards growth takes place. The height growth curves for the individual provenances during the 25-years period (with exception of the provenance from Marcule) fall within the interval {+-} 0,5S from the compensated curve for the entire population studied. All larch provenances in the experiment had reached the height growth culmination. A greatest differentiation in respect of this character occurred in case of the provenances from Sudetes. 27 refs, 4 figs, 8 tabs

  1. Growth dynamics variation of different larch provenances under the mountain conditions in Poland

    Energy Technology Data Exchange (ETDEWEB)

    Kulej, M [Univ. of Agriculture, Cracow (Poland). Section of Seed Production and Selection

    1996-12-31

    The results of 25-year investigations based on measurements and statistical analysis concerning the growth dynamics variation of larch provenances from the entire area of Poland are reported in this paper. This is the first larch provenance experiment in Poland under mountain conditions. The results obtained showed a significant variability among the provenances tested as regards the basic growth characters (height, d.b.h., growth index) at the age of 5, 8, 11, 15, 20 and 25 years. The larch from Klodzko and Proszkow turned out to be the best in respect of growth during the entire 25-years period. Decidedly bad were provenances from Marcule, Grojec, Rawa mazowiecka and Kroscienko. We cannot forecast the future growth of larch when trees are 5-years old since such prognosis may carry an error. However, on the basis of the results obtained it may be concluded that when trees are about 8 years old the stabilization of the position of individual provenances as regards growth takes place. The height growth curves for the individual provenances during the 25-years period (with exception of the provenance from Marcule) fall within the interval {+-} 0,5S from the compensated curve for the entire population studied. All larch provenances in the experiment had reached the height growth culmination. A greatest differentiation in respect of this character occurred in case of the provenances from Sudetes. 27 refs, 4 figs, 8 tabs

  2. Diffusive growth of a single droplet with three different boundary conditions

    Science.gov (United States)

    Tavassoli, Z.; Rodgers, G. J.

    2000-02-01

    We study a single, motionless three-dimensional droplet growing by adsorption of diffusing monomers on a 2D substrate. The diffusing monomers are adsorbed at the aggregate perimeter of the droplet with different boundary conditions. Models with both an adsorption boundary condition and a radiation boundary condition, as well as a phenomenological model, are considered and solved in a quasistatic approximation. The latter two models allow particle detachment. In the short time limit, the droplet radius grows as a power of the time with exponents of 1/4, 1/2 and 3/4 for the models with adsorption, radiation and phenomenological boundary conditions, respectively. In the long time limit a universal growth rate as $[t/\\ln(t)]^{1/3}$ is observed for the radius of the droplet for all models independent of the boundary conditions. This asymptotic behaviour was obtained by Krapivsky \\cite{krapquasi} where a similarity variable approach was used to treat the growth of a droplet with an adsorption boundary condition based on a quasistatic approximation. Another boundary condition with a constant flux of monomers at the aggregate perimeter is also examined. The results exhibit a power law growth rate with an exponent of 1/3 for all times.

  3. Influence of culture conditions on growth and protein metabolism in chlorella pyranosides

    International Nuclear Information System (INIS)

    Mazon Matanzo, M. P.; Fernandez Gonzalez, J.; Batuecas Suarez, B.

    1981-01-01

    Growth and protein metabolism of Chlorella pyranoside under different conditions of temperature, photo period and CO 2 concentration was studied. The optimum of biomass production was observed at 25 degree centigree, 40.000 ppm of CO 2 in air and a 20 h. light period, followed of 4 h. of darkness. Some variations in free aminoacids content was observed under different conditions but no change did occur in protein. (Author) 68 refs

  4. Influence of culture conditions on growth and protein metabolism in chlorella pyrenoidosa

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Mazon, M.P.; Batuecas, B.

    1981-01-01

    Growth and protein metabolism of chlorella pyrenoidosa under differents conditions of temperature, photoperiod and CO 2 concentration was studied. The optimum of biomas production was observed at 25 deg C, 40.000 ppm of CO 2 in air and a 20 h. light period, followed of 4 h. of darkness. Some variations in free aminoacids content was observed under differents conditions but no change did occur in protein. (author)

  5. Enhanced shoot investment makes invasive plants exhibit growth advantages in high nitrogen conditions.

    Science.gov (United States)

    Liu, X A; Peng, Y; Li, J J; Peng, P H

    2018-03-12

    Resource amendments commonly promote plant invasions, raising concerns over the potential consequences of nitrogen (N) deposition; however, it is unclear whether invaders will benefit from N deposition more than natives. Growth is among the most fundamental inherent traits of plants and thus good invaders may have superior growth advantages in response to resource amendments. We compared the growth and allocation between invasive and native plants in different N regimes including controls (ambient N concentrations). We found that invasive plants always grew much larger than native plants in varying N conditions, regardless of growth- or phylogeny-based analyses, and that the former allocated more biomass to shoots than the latter. Although N addition enhanced the growth of invasive plants, this enhancement did not increase with increasing N addition. Across invasive and native species, changes in shoot biomass allocation were positively correlated with changes in whole-plant biomass; and the slope of this relationship was greater in invasive plants than native plants. These findings suggest that enhanced shoot investment makes invasive plants retain a growth advantage in high N conditions relative to natives, and also highlight that future N deposition may increase the risks of plant invasions.

  6. Stand conditions immediately following a restoration harvest in an old-growth pine-hardwood remnant

    Science.gov (United States)

    D. C. Bragg

    2010-01-01

    Portions of the Levi Wilcoxon Demonstration Forest (LWDF), a privately owned parcel of old-growth pine and hardwoods in Ashley County, Arkansas, were recently treated to restore conditions similar to some historic accounts of the virgin forest. Following a hardwood-only cut, a post-harvest inventory showed that the number of tree species in the sample area declined...

  7. Spatial variation in growth, condition and maturation reaction norms of the Baltic herring Clupea harengus membras

    NARCIS (Netherlands)

    Vainikka, A.; Mollet, F.M.; Casini, M.; Gardmark, A.

    2009-01-01

    Understanding of spatial patterns in life-history traits can help fisheries management focus on biologically and functionally relevant stock units. In the present study, we examined life-history variation in growth, condition and maturation of the Baltic herring Clupea harengus membras among

  8. Using time-dependent models to investigate body condition and growth rate of the giant gartersnake

    Science.gov (United States)

    Coates, P.S.; Wylie, G.D.; Halstead, B.J.; Casazza, Michael L.

    2009-01-01

    Identifying links between phenotypic attributes and fitness is a primary goal of reproductive ecology. Differences in within-year patterns of body condition between sexes of gartersnakes in relation to reproduction and growth are not fully understood. We conducted an 11-year field study of body condition and growth rate of the giant gartersnake Thamnophis gigas across 13 study areas in the Central Valley of California, USA. We developed a priori mixed effects models of body condition index (BCI), which included covariates of time, sex and snout-vent length and reported the best-approximating models using an information theoretic approach. Also, we developed models of growth rate index (GRI) using covariates of sex and periods based on reproductive behavior. The largest difference in BCI between sexes, as predicted by a non-linear (cubic) time model, occurred during the mating period when female body condition (0.014??0.001 se) was substantially greater than males (-0.027??0.002 se). Males likely allocated energy to search for mates, while females likely stored energy for embryonic development. We also provided evidence that males use more body energy reserves than females during hibernation, perhaps because of different body temperatures between sexes. We found GRI of male snakes was substantially lower during the mating period than during a non-mating period, which indicated that a trade-off existed between searching for mates and growth. These findings contribute to our understanding of snake ecology in a Mediterranean climate. ?? 2009 The Zoological Society of London.

  9. Individual Differences in the Expression of Conditioned Fear Are Associated with Endogenous Fibroblast Growth Factor 2

    Science.gov (United States)

    Graham, Bronwyn M.; Richardson, Rick

    2016-01-01

    These experiments examined the relationship between the neurotrophic factor fibroblast growth factor 2 (FGF2) and individual differences in the expression of conditioned fear. Experiments 1 and 2 demonstrated that rats naturally expressing low levels of contextual or cued fear have higher levels of hippocampal FGF2 relative to rats that express…

  10. Deep Soil Conditions Make Mediterranean Cork Oak Stem Growth Vulnerable to Autumnal Rainfall Decline in Tunisia

    Directory of Open Access Journals (Sweden)

    Lobna Zribi

    2016-10-01

    Full Text Available Tree rings provide fruitful information on climate features driving annual forest growth through statistical correlations between annual tree growth and climate features. Indices built upon tree growth limitation by carbon sequestration (source hypothesis or drought-driven cambial phenology (sink hypothesis can be used to better identify underlying processes. We used both analytical frameworks on Quercus suber, a sparsely studied species due to tree ring methodological issues, and growing on a favorable sub-humid Mediterranean climate and deep soil conditions in Tunisia (North Africa. Statistical analysis revealed the major role of autumnal rainfall before the growing season on annual tree growth over the 1918–2008 time series. Using a water budget model, we were able to explain the critical role of the deep soil water refill during the wet season in affecting both the drought onset controlling growth phenology and the summer drought intensity affecting carbon assimilation. Analysis of recent climate changes in the region additionally illustrated an increase in temperatures enhancing the evaporative demand and advancing growth start, and a decline in rainfalls in autumn, two key variables driving stem growth. We concluded on the benefits of using process-based indices in dendrochronological analysis and identified the main vulnerability of this Mediterranean forest to autumnal rainfall decline, a peculiar aspect of climate change under summer-dry climates.

  11. A theory of economic growth with material/energy resources and dematerialization: interaction of three growth mechanisms

    NARCIS (Netherlands)

    Ayes, R.U.; van den Bergh, J.C.J.M.

    2005-01-01

    The nature of energy and material resources in a non-optimizing growth theory framework is clarified. This involves two modifications of the conventional theory. Firstly, multiple feedback mechanisms or "growth engines" are identified, such that the impact of the cost of production through demand on

  12. Kinetic modeling of growth and lipid body induction in Chlorella pyrenoidosa under heterotrophic conditions.

    Science.gov (United States)

    Sachdeva, Neha; Kumar, G Dinesh; Gupta, Ravi Prakash; Mathur, Anshu Shankar; Manikandan, B; Basu, Biswajit; Tuli, Deepak Kumar

    2016-10-01

    The aim of the present work was to develop a mathematical model to describe the biomass and (total) lipid productivity of Chlorella pyrenoidosa NCIM 2738 under heterotrophic conditions. Biomass growth rate was predicted by Droop's cell quota model, while changes observed in cell quota (utilization) under carbon excess conditions were used for the modeling and predicting the lipid accumulation rate. The model was simulated under non-limiting (excess) carbon and limiting nitrate concentration and validated with experimental data for the culture grown in batch (flask) mode under different nitrate concentrations. The present model incorporated two modes (growth and stressed) for the prediction of endogenous lipid synthesis/induction and aimed to predict the effect and response of the microalgae under nutrient starvation (stressed) conditions. MATLAB and Genetic Algorithm were employed for the prediction and validation of the model parameters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Metabolite profiling uncovers plasmid-induced cobalt limitation under methylotrophic growth conditions.

    Directory of Open Access Journals (Sweden)

    Patrick Kiefer

    2009-11-01

    Full Text Available The introduction and maintenance of plasmids in cells is often associated with a reduction of growth rate. The reason for this growth reduction is unclear in many cases.We observed a surprisingly large reduction in growth rate of about 50% of Methylobacterium extorquens AM1 during methylotrophic growth in the presence of a plasmid, pCM80 expressing the tetA gene, relative to the wild-type. A less pronounced growth delay during growth under non-methylotrophic growth conditions was observed; this suggested an inhibition of one-carbon metabolism rather than a general growth inhibition or metabolic burden. Metabolome analyses revealed an increase in pool sizes of ethylmalonyl-CoA and methylmalonyl-CoA of more than 6- and 35-fold, respectively, relative to wild type, suggesting a strongly reduced conversion of these central intermediates, which are essential for glyoxylate regeneration in this model methylotroph. Similar results were found for M. extorquens AM1 pCM160 which confers kanamycin resistance. These intermediates of the ethylmalonyl-CoA pathway have in common their conversion by coenzyme B(12-dependent mutases, which have cobalt as a central ligand. The one-carbon metabolism-related growth delay was restored by providing higher cobalt concentrations, by heterologous expression of isocitrate lyase as an alternative path for glyoxylate regeneration, or by identification and overproduction of proteins involved in cobalt import.This study demonstrates that the introduction of the plasmids leads to an apparent inhibition of the cobalt-dependent enzymes of the ethylmalonyl-CoA pathway. Possible explanations are presented and point to a limited cobalt concentration in the cell as a consequence of the antibiotic stress.

  14. Maximizing signal-to-noise ratio (SNR) in 3-D large bandgap semiconductor pixelated detectors in optimal and non-optimal filtering conditions

    International Nuclear Information System (INIS)

    Rodrigues, Miesher L.; Serra, Andre da S.; He, Zhong; Zhu, Yuefeng

    2009-01-01

    3-D pixelated semiconductor detectors are used in radiation detection applications requiring spectroscopic and imaging information from radiation sources. Reconstruction algorithms used to determine direction and energy of incoming gamma rays can be improved by reducing electronic noise and using optimum filtering techniques. Position information can be improved by achieving sub-pixel resolution. Electronic noise is the limiting factor. Achieving sub-pixel resolution - position of the interaction better than one pixel pitch - in 3-D pixelated semiconductor detectors is a challenging task due to the fast transient characteristics of these signals. This work addresses two fundamental questions: the first is to determine the optimum filter, while the second is to estimate the achievable sub-pixel resolution using this filter. It is shown that the matched filter is the optimum filter when applying the signal-to-noise ratio criteria. Also, non-optimum filters are studied. The framework of 3-D waveform simulation using the Shockley-Ramo Theorem and the Hecht Equation for electron and hole trapping is presented in this work. This waveform simulator can be used to analyze current detectors as well as explore new ideas and concepts in future work. Numerical simulations show that assuming an electronic noise of 3.3 keV it is possible to subdivide the pixel region into 5x5 sub-pixels. After analyzing these results, it is suggested that sub-pixel information can also improve energy resolution. Current noise levels present the major drawback to both achieve sub-pixel resolution as well as improve energy resolution below the current limits. (author)

  15. Evaluation of growth and flowering of Chenopodium quinoa Willd. under Polish conditions

    Directory of Open Access Journals (Sweden)

    Krzysztof Gęsiński

    2012-12-01

    Full Text Available The material presented refers to the estimation of growth and the flowering (Chenopodium quinoa Willd. under Polish conditions. The species has been a South-American pseudocereal cultivated in the traditional form in the Andean region for over 5 thousand years. Its advantage, apart from low soil and climate requirements, is that it shows high nutritive value. The Chenopodium quinoa protein is especially valuable with its amino acid composition which is better balanced than that of wheat or maize. It shows a better share of egzogenic aminoacids. Field examinations were carried out in 1999-2001 at the Experiment Station of Cultivar Testing at Chrząstowo. The experiment involved two cultivars from two various growing regions: America and Europe. Analyses were made to include development stages, plant growth dynamics, inflorescences development dynamics, inflorescence habit and flowering. Differences were recorded in the growth and development models of the cultivars researched. The European cultivar had a short compact inflorescence with a short flowering period, reaching 120 cm. American cultivar plants were high (160 cm; they showed a slower continuous growth, loose big-in-size inflorescence, and a long period of flowering. The plants ended their growing season over the flowering stage or seed formation. The adequate growth, the course of flowering and, as a result, a stable yielding of the European cultivar make the group suitable for the cultivation under Polish conditions. This breeding group should also be the parent material for the cultivation of the Polish cultivar of Chenopodium quinoa.

  16. Conditional expression of constitutively active estrogen receptor {alpha} in chondrocytes impairs longitudinal bone growth in mice

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Kazuhiro [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Tsukui, Tohru [Experimental Animal Laboratory, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Imazawa, Yukiko; Horie-Inoue, Kuniko [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Inoue, Satoshi, E-mail: INOUE-GER@h.u-tokyo.ac.jp [Division of Gene Regulation and Signal Transduction, Research Center for Genomic Medicine, Saitama Medical University, Saitama (Japan); Department of Geriatric Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan); Department of Anti-Aging Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo (Japan)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer Conditional transgenic mice expressing constitutively active estrogen receptor {alpha} (caER{alpha}) in chondrocytes were developed. Black-Right-Pointing-Pointer Expression of caER{alpha} in chondrocytes impaired longitudinal bone growth in mice. Black-Right-Pointing-Pointer caER{alpha} affects chondrocyte proliferation and differentiation. Black-Right-Pointing-Pointer This mouse model is useful for understanding the physiological role of ER{alpha}in vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caER{alpha}{sup ColII}, expressing constitutively active mutant estrogen receptor (ER) {alpha} in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caER{alpha}{sup ColII} mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caER{alpha}{sup ColII} mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caER{alpha}{sup ColII} mice. These results suggest that ER{alpha} is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

  17. Conditional expression of constitutively active estrogen receptor α in chondrocytes impairs longitudinal bone growth in mice

    International Nuclear Information System (INIS)

    Ikeda, Kazuhiro; Tsukui, Tohru; Imazawa, Yukiko; Horie-Inoue, Kuniko; Inoue, Satoshi

    2012-01-01

    Highlights: ► Conditional transgenic mice expressing constitutively active estrogen receptor α (caERα) in chondrocytes were developed. ► Expression of caERα in chondrocytes impaired longitudinal bone growth in mice. ► caERα affects chondrocyte proliferation and differentiation. ► This mouse model is useful for understanding the physiological role of ERαin vivo. -- Abstract: Estrogen plays important roles in the regulation of chondrocyte proliferation and differentiation, which are essential steps for longitudinal bone growth; however, the mechanisms of estrogen action on chondrocytes have not been fully elucidated. In the present study, we generated conditional transgenic mice, designated as caERα ColII , expressing constitutively active mutant estrogen receptor (ER) α in chondrocytes, using the chondrocyte-specific type II collagen promoter-driven Cre transgenic mice. caERα ColII mice showed retardation in longitudinal growth, with short bone lengths. BrdU labeling showed reduced proliferation of hypertrophic chondrocytes in the proliferating layer of the growth plate of tibia in caERα ColII mice. In situ hybridization analysis of type X collagen revealed that the maturation of hypertrophic chondrocytes was impaired in caERα ColII mice. These results suggest that ERα is a critical regulator of chondrocyte proliferation and maturation during skeletal development, mediating longitudinal bone growth in vivo.

  18. Influence of Different Growth Conditions on the Kefir Grains Production, used in the Kefiran Synthesis

    Directory of Open Access Journals (Sweden)

    Carmen Rodica Pop

    2014-11-01

    Full Text Available The purpose of this study was to optimize the kefir grains biomass production, using milk as culture media. The kefir grains were cultured at different changed conditions (temperature, time, shaker rotating speed, culture media supplemented to evaluate their effects. Results showed that optimal culture conditions were using the organic skim milk, incubated at 25°C for 24 hours with a rotation rate of 125 rpm. According to results, the growth rate was 38.9 g/L for 24 h, at 25°C using the organic milk - OSM, 36.87 g/L during 24 hours, optimal time for propagation process gave 37.93 g/L kefir grains biomass when the effect of temperature level was tested. The homogenization of medium with shaker rotating induced a greater growth rate, it was obtained 38.9 g/L for 24 h, at 25°C using rotation rate at 125 rpm. The growing medium (conventional milk supplemented with different minerals and vitamins may lead to improve the growth conditions of kefir grains biomass. The optimization of the growth environment is very important for achieving the maximum production of kefir grains biomass, substrate necessary to obtain the polysaccharide kefiran

  19. Unfolded protein response is required for Aspergillus oryzae growth under conditions inducing secretory hydrolytic enzyme production.

    Science.gov (United States)

    Tanaka, Mizuki; Shintani, Takahiro; Gomi, Katsuya

    2015-12-01

    Unfolded protein response (UPR) is an intracellular signaling pathway for adaptation to endoplasmic reticulum (ER) stress. In yeast UPR, Ire1 cleaves the unconventional intron of HAC1 mRNA, and the functional Hac1 protein translated from the spliced HAC1 mRNA induces the expression of ER chaperone genes and ER-associated degradation genes for the refolding or degradation of unfolded proteins. In this study, we constructed an ireA (IRE1 ortholog) conditionally expressing strain of Aspergillus oryzae, a filamentous fungus producing a large amount of amylolytic enzymes, and examined the contribution of UPR to ER stress adaptation under physiological conditions. Repression of ireA completely blocked A. oryzae growth under conditions inducing the production of hydrolytic enzymes, such as amylases and proteases. This growth defect was restored by the introduction of unconventional intronless hacA (hacA-i). Furthermore, UPR was observed to be induced by amylolytic gene expression, and the disruption of the transcriptional activator for amylolytic genes resulted in partial growth restoration of the ireA-repressing strain. In addition, a homokaryotic ireA disruption mutant was successfully generated using the strain harboring hacA-i as a parental host. These results indicated that UPR is required for A. oryzae growth to alleviate ER stress induced by excessive production of hydrolytic enzymes. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Bulk water phase and biofilm growth in drinking water at low nutrient conditions.

    Science.gov (United States)

    Boe-Hansen, Rasmus; Albrechtsen, Hans-Jørgen; Arvin, Erik; Jørgensen, Claus

    2002-11-01

    In this study, the bacterial growth dynamics of a drinking water distribution system at low nutrient conditions was studied in order to determine bacterial growth rates by a range of methods, and to compare growth rates in the bulk water phase and the biofilm. A model distribution system was used to quantify the effect of retention times at hydraulic conditions similar to those in drinking water distribution networks. Water and pipe wall samples were taken and examined during the experiment. The pipes had been exposed to drinking water at approximately 13 degrees C, for at least 385 days to allow the formation of a mature quasi-stationary biofilm. At retention times of 12 h, total bacterial counts increased equivalent to a net bacterial growth rate of 0.048 day(-1). The bulk water phase bacteria exhibited a higher activity than the biofilm bacteria in terms of culturability, cell-specific ATP content, and cell-specific leucine incorporation rate. Bacteria in the bulk water phase incubated without the presence of biofilm exhibited a bacterial growth rate of 0.30 day(-1). The biofilm was radioactively labelled by the addition of 14C-benzoic acid. Subsequently, a biofilm detachment rate of 0.013 day(-1) was determined by measuring the release of 14C-labelled bacteria of the biofilm. For the quasi-stationary phase biofilm, the detachment rate was equivalent to the net growth rate. The growth rates determined in this study by different independent experimental approaches were comparable and within the range of values reported in the literature.

  1. Controlling the site density of multiwall carbon nanotubes via growth conditions

    Science.gov (United States)

    Siegal, M. P.; Overmyer, D. L.; Kaatz, F. H.

    2004-06-01

    We present two complementary methods for controlling the site density of multiwall carbon nanotubes (CNTs) directly as a function of growth conditions from 1011to107CNTs/cm2. Several potential applications require significant spacing between individual CNTs. The first method shows that the site density varies with the heat of formation of the hydrocarbon gas used during CNT growth by thermal chemical vapor deposition. The second method demonstrates that the site density decreases with increasing residual stress of the metal catalyst/diffusion barrier layers. These methods are combined for wide-range control of CNT site density.

  2. In vitro maintenance, under slow-growth conditions, of oil palm germplasm obtained by embryo rescue

    Directory of Open Access Journals (Sweden)

    Julcéia Camillo

    2015-05-01

    Full Text Available The objective of this work was to evaluate the in vitro maintenance of oil palm (Elaeis guineensis and E. oleifera accessions under slow-growth conditions. Plants produced by embryo rescue were subject to 1/2MS culture medium supplemented with the carbohydrates sucrose, mannitol, and sorbitol at 1, 2, and 3% under 20 and 25±2ºC. After 12 months, the temperature of 20°C reduced plant growth. Sucrose is the most appropriate carbohydrate for maintaining the quality of the plants, whereas mannitol and sorbitol result in a reduced plant survival.

  3. Seasonal carbon storage and growth in Mediterranean tree seedlings under different water conditions.

    Science.gov (United States)

    Sanz-Pérez, Virginia; Castro-Díez, Pilar; Joffre, Richard

    2009-09-01

    In all Mediterranean-type ecosystems, evergreen and deciduous trees differing in wood anatomy, growth pattern and leaf habit coexist, suggesting distinct adaptative responses to environmental constraints. This study examined the effects of summer water stress on carbon (C) storage and growth in seedlings of three coexisting Mediterranean trees that differed in phenology and wood anatomy characteristics: Quercus ilex subsp. ballota (Desf.) Samp., Quercus faginea Lam. and Pinus halepensis L. Seedlings were subjected to two levels of watering during two consecutive summers and achieved a minimum of -0.5 and -2.5 MPa of predawn water potential in the control and water stress treatment, respectively. Both Quercus species concentrated their growth in the early growing season, demanding higher C in early spring but replenishing C-stores in autumn. These species allocated more biomass to roots, having larger belowground starch and lipid reserves. Quercus species differed in seasonal storage dynamics from P. halepensis. This species allocated most of its C to aboveground growth, which occurred gradually during the growing season, leading to fewer C-reserves. Soluble sugar and starch concentrations sharply declined in August in P. halepensis, probably because reserves support respiration demands as this species closed stomata earlier under water stress. Drought reduced growth of the three species, mainly in Q. faginea and P. halepensis, but not C-reserves, suggesting that growth under water stress conditions is not limited by C-availability.

  4. Growth, Toxin Production and Allelopathic Effects of Pseudo-nitzschia multiseries under Iron-Enriched Conditions

    Directory of Open Access Journals (Sweden)

    Bruna Fernanda Sobrinho

    2017-10-01

    Full Text Available In order to assess the effects of Fe-enrichment on the growth and domoic acid (DA production of the toxigenic diatom Pseudo-nitzschia multiseries, static cultures that received the addition of different iron (Fe concentrations were maintained for 30 days. Intra- and extracellular DA concentrations were evaluated over time, and growth and chain-formation were compared to those of non-toxic diatoms, Bacillaria sp. Growth rates of P. multiseries (μ = 0.45–0.73 d−1 were similar among cultures containing different Fe concentrations. Likewise, the similar incidence and length of P. multiseries stepped cell chains (usually 2–4; up to 8-cell long among the treatments reinforces that the cultures were not growth-inhibited under any condition tested, suggesting an efficient Fe acquisition mechanism. Moreover, DA concentrations were significantly higher under the highest Fe concentration, indicating that Fe is required for toxin synthesis. Bacillaria sp. reached comparable growth rates under the same Fe concentrations, except when the dissolved cell contents from a P. multiseries culture was added. The 50–70% reduction in cell density and 70–90% decrease in total chlorophyll-a content of Bacillaria sp. at early stationary growth phase indicates, for the first time, an allelopathic effect of undetermined compounds released by Pseudo-nitzschia to another diatom species.

  5. 3-D simulations to investigate initial condition effects on the growth of Rayleigh-Taylor mixing

    Energy Technology Data Exchange (ETDEWEB)

    Andrews, Malcolm J [Los Alamos National Laboratory

    2008-01-01

    The effect of initial conditions on the growth rate of turbulent Rayleigh-Taylor (RT) mixing has been studied using carefully formulated numerical simulations. An integrated large-eddy simulation (ILES) that uses a finite-volume technique was employed to solve the three-dimensional incompressible Euler equations with numerical dissipation. The initial conditions were chosen to test the dependence of the RT growth parameters ({alpha}{sub b}, {alpha}{sub s}) on variations in (a) the spectral bandwidth, (b) the spectral shape, and (c) discrete banded spectra. Our findings support the notion that the overall growth of the RT mixing is strongly dependent on initial conditions. Variation in spectral shapes and bandwidths are found to have a complex effect of the late time development of the RT mixing layer, and raise the question of whether we can design RT transition and turbulence based on our choice of initial conditions. In addition, our results provide a useful database for the initialization and development of closures describing RT transition and turbulence.

  6. Effect of Salicylic Acid on the Growth and Physiological Characteristics of Maize under Stress Conditions

    International Nuclear Information System (INIS)

    Manzoor, K.; Ilyas, N.; Batool, N.; Arshad, M.; Ahmad, B.

    2015-01-01

    Salicylic acid (SA) is a naturally occurring signaling molecule and growth regulator that enhances plant growth particularly in stress conditions. The present study was planned to evaluate the effects of different levels of SA on maize growth under drought and salt stress conditions. An experiment was conducted to test the morphological, physiological and biochemical changes in two cultivar of maize D-1184 and TG-8250. Varying levels of salicylic acid, i.e. 5mM, 10mM and 15mM were applied through foliar method. Exogenous applications of salicylic acid were done after 20 days of germination of the maize plants. Salicylic acid significantly affects root and shoot dry matter under drought and salt stress. Foliar application of SA significantly increased proline concentration (11 percentage and 12 percentage), amino acid accumulation (25 percentage and 18 percentage), relative water (17 percentage and 14 percentage) and Chlorophyll content. Overall, it can be concluded that SA at lower concentration is effective to minimize the effect of stress conditions. Maize cultivar TG-8250 showed better tolerance under drought and salt stress condition as compared to D-1184 cultivar. (author)

  7. Effect of Water Deficit Stress on Peach Growth under Commercial Orchard Management Conditions

    Directory of Open Access Journals (Sweden)

    M. Rahmati

    2015-06-01

    Full Text Available In order to study the sensitivity of vegetative growth to water deficit stress of a late-maturing peach (Prunus persica L. cv. Elberta under orchard conditions, an experiment was conducted as randomized complete-block design with three treatments and four repetitions in Shahdiran commercial orchard in Mashhad during 2011. Three irrigation treatments including 360 (low stress, 180 (moderate stress and 90 (severe stress m3ha-1week-1 using a drip irrigation system (minimum stem water potential near harvest: -1.2, -1.5 and -1.7 MPa, respectively from the mid-pit hardening stage (12th of June until harvest (23rd of Sep. applied. Predawn, stem and leaf water potentials, leaf photosynthesis, transpiration, stomatal conductance and leaf temperature, the number of new shoots on fruit bearing shoots and vegetative shoots lengths during growing season as well as leaf area at harvest were measured. The results showed that water deficit stress had negative effects on peach tree water status, thereby resulting in decreased leaf gas exchange and tree vegetative growth. As significant decreased assimilate production of tree was resulted from both decreased leaf assimilation rate (until about 23 % and 50 %, respectively under moderate and severe stress conditions compared to low stress conditions and decreased leaf area of tree (until about 57% and 79%, respectively under moderate and severe stress conditions compared to low stress conditions at harvest. The significant positive correlation between leaf water potential and vegetative growth of peach revealed that shoot growth would decrease by 30% and 50% of maximum at leaf water potential of –1.56 and –2.30 MPa, respectively.

  8. Characterization of thermoset and thermoplastic polyurethane pads, and molded and non-optimized machined grooving methods for oxide chemical mechanical planarization applications

    International Nuclear Information System (INIS)

    Sampurno, Yasa; Borucki, Leonard; Zhuang, Yun; Misra, Sudhanshu; Holland, Karey; Boning, Duane; Philipossian, Ara

    2009-01-01

    This paper systematically studies the effect of pad material, grooving method and grooving pattern on interlayer dielectric chemical mechanical planarization. The tested polishing pads consist of thermoplastic and thermoset polyurethanes synthesized using two different processes. Grooves created using a molding technique are compared with grooves formed by mechanical cutting. The concentric groove design is also compared with the logarithmic positive spiral positive grooving design. Experimental data collected include removal rate, coefficient of friction, shear force variance, pad temperature and dynamic mechanical analyzer measurements. Scanning electron microscope images are used to correlate grooving methods with coefficient of friction and shear force variance measurements. Results show that all of the pads polish wafers in boundary lubrication mode with unique friction coefficient, shear force variance and pad temperature characteristics. Simulations using a two-step removal rate mechanism are performed to estimate the chemical and mechanical rate constants. The analysis indicates that the thermoplastic pad is more mechanically controlled than the thermoset pad and that molded grooving induces a more mechanically controlled process than non-optimized machined grooving

  9. Effect of Different Growth Conditions on Certain Biochemical Parameters of Different Cyanobacterial Strains

    Directory of Open Access Journals (Sweden)

    Hammouda, O. E.

    2012-01-01

    Full Text Available Aims: Variation in the traditional growth medium conditions to enhance the production of lipids, carbohydrates, protein and the free amino acids content of three cyanobacterial species. Methodology and Results: Three species of cyanobacteria (Anabaena laxa, Anabaena fertilissima and Nostoc muscorum were collected from the culture collection of Soils, Water and Environment Research Institute, Agriculture Research Center, Giza, Egypt, to investigate their biochemical composition under different growth conditions, using BG110 (nitrogen free as growth medium. These conditions were represented by control medium, static glucose medium with (1%, w/v, aerated medium (aerated by bubbling technique depending on CO2 normally existed in air with a concentration of 0.03%, molasses medium (0.7%, v/v and aerated medium enriched with glucose (1%, w/v. Lipid content, total carbohydrates, soluble proteins and free amino acids were determined at the previous conditions. Glucose at 0.7% (w/v was the most favorable for lipid production in A. laxa, where it exhibited the highest lipid content (427 μg/g fresh wt.. Increasing molasses concentration up to 0.7% (v/v produced an increase in lipid contents of the tested cyanobacterial strains. The highest lipid content of both N. muscorum (366.2 μg/g fresh wt. and A. laxa (357.4 μg/g fresh wt. were recorded at molasses concentrations of 0.1 and 0.7% (v/v, respectively. A. laxa expressed high significant values for both proteins (31.6 μg/mL and free amino acids (40.5 mg/g dry wt. after 6 days of incubation period under aerated enriched glucose condition (1%, w/v. Also, at the same growth conditions, A. fertilissima exhibited high significant values for carbohydrates at 4th day (876.8 mg/g dry wt.. Conclusion, significance and impact of study: Aerated enriched glucose medium (1%, w/v was the best growth medium condition used in the present study.

  10. In vitro conservation of Piper aduncum and Piper hispidinervum under slow-growth conditions

    Directory of Open Access Journals (Sweden)

    Tatiane Loureiro da Silva

    2011-04-01

    Full Text Available The objective of this work was to evaluate in vitro storage of Piper aduncum and P. hispidinervum under slow-growth conditions. Shoots were stored at low temperatures (10, 20 and 25°C, and the culture medium was supplemented with osmotic agents (sucrose and mannitol - at 1, 2 and 3% and abiscisic acid - ABA (0, 0.5, 1.0, 2.0 and 3.0 mg L-1. After six-months of storage, shoots were evaluated for survival and regrowth. Low temperature at 20ºC was effective for the in vitro conservation of P. aduncum and P. hispidinervum shoots. In vitro cultures maintained at 20ºC on MS medium showed 100% survival with slow-growth shoots. The presence of mannitol or ABA, in the culture medium, negatively affected shoot growth, which is evidenced by the low rate of recovered shoots.

  11. A necessary condition for dispersal driven growth of populations with discrete patch dynamics.

    Science.gov (United States)

    Guiver, Chris; Packman, David; Townley, Stuart

    2017-07-07

    We revisit the question of when can dispersal-induced coupling between discrete sink populations cause overall population growth? Such a phenomenon is called dispersal driven growth and provides a simple explanation of how dispersal can allow populations to persist across discrete, spatially heterogeneous, environments even when individual patches are adverse or unfavourable. For two classes of mathematical models, one linear and one non-linear, we provide necessary conditions for dispersal driven growth in terms of the non-existence of a common linear Lyapunov function, which we describe. Our approach draws heavily upon the underlying positive dynamical systems structure. Our results apply to both discrete- and continuous-time models. The theory is illustrated with examples and both biological and mathematical conclusions are drawn. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Uropathogenic Escherichia coli Express Type 1 Fimbriae Only in Surface Adherent Populations Under Physiological Growth Conditions

    DEFF Research Database (Denmark)

    Stærk, Kristian; Kolmos, Hans Jørn; Khandige, Surabhi

    2016-01-01

    were correlated with the ability to adhere to and invade cultured human bladder cells. RESULTS:  Although inactive during planktonic growth in urine, T1F expression occurs when UPEC settles on and infects bladder epithelial cells or colonizes catheters. As a result, UPEC in these sessile populations...... with increased expression during surface growth adaptation and infection of uroepithelial cells. This leads to separation of UPEC into low-expression planktonic populations and high-expression sessile populations....... enhances bladder cell adhesion and invasion potential. Only T1F-negative UPEC are subsequently released to the urine, thus limiting T1F expression to surface-associated UPEC alone. CONCLUSION:  Our results demonstrate that T1F expression is strictly regulated under physiological growth conditions...

  13. Growth and Survival of Some Probiotic Strains in Simulated Ice Cream Conditions

    Science.gov (United States)

    Homayouni, A.; Ehsani, M. R.; Azizi, A.; Razavi, S. H.; Yarmand, M. S.

    A Completely Randomized Design (CRD) experiment was applied in triplicates to evaluate the survival of four probiotic strains in simulated ice cream conditions. The growth and survival rate of these probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Bifidobacterium bifidum and Bifidobacterium longum) in varying amount of sucrose (10, 15, 20 and 25%), oxygen scavenging components (0.05% L-cysteine and 0.05% L-ascorbate) and temperatures (4 and -20°C) during different periods of time (1, 2 and 3 months) were evaluated in MRS-broth medium. Optical density at 580 nm was used to measure growth. Lactobacilli strains proved to be highly resistant in comparison with Biffidobacteria strains. The viable cell number of Lactobacillus casei in different sucrose concentrations, different oxidoreduction potentials and refrigeration temperature was 1x1010, 2x108 and 5x107 cfu mL-1, respectively. Growth and survival rate of Lactobacillus casei showed to be the highest.

  14. THE EMPLOYMENT – PRODUCTIVITY – SALARY RELATION, A CONDITION FOR ACHIEVING LONG - TERM ECONOMIC GROWTH

    Directory of Open Access Journals (Sweden)

    Mihai CHIRILA

    2005-01-01

    Full Text Available The employment-productivity-salary correlation is essential towards setting up conditions for economic growth andlasting social stability. An influence exists from technological changes, current stage of economic development,peculiarities of labour offer, employers – trade-unions interaction, etc. The analysis covers long-term and short-termcycles. In keeping with specificity of development stages, national economy witnesses an interval of productivitygrowth facilitating maximized employment and a rise in salary too. A lower growth rate indicates difficulties inassimilating new technologies; a higher growth rate generates instability in employing labour. Thus, the exercise ofstrong pressure is shown to exist on economic and technological structures. Likewise, this is what happens whenproductivity goes ahead of the separate analyses of the correlations between employment and productivity, on theone hand, and productivity and salary, on the other.

  15. Feeding behaviour and growth of the Peruvian scallop (Argopecten purpuratus) under daily cyclic hypoxia conditions

    Science.gov (United States)

    Aguirre-Velarde, Arturo; Jean, Fred; Thouzeau, Gérard; Flye-Sainte-Marie, Jonathan

    2018-01-01

    As a secondary consequence of the high productivity of the upwelling system, organisms inhabiting Peruvian coastal bays are frequently exposed to hypoxic conditions. The aim of the present paper was to investigate the effects of daily-cyclic-severe hypoxia on energetics of a species presenting little escape ability when facing hypoxia. For this purpose, juvenile Peruvian scallops (Argopecten purpuratus) were exposed to four experimental conditions: fed and starved, combined or not to nightly severe hypoxia (5% oxygen saturation) for ≈ 12 h over a 21-day experiment. In both fed conditions, clearance rate was measured by the mean of an open-flow system. Our results indicate that the Peruvian scallop is able to maintain an active filtration even at low oxygen saturation, at least during expositions up to 12 h. During the first phase of exposure to hypoxia, clearance rate decreased abruptly when oxygen saturation dropped below 10%, but rapidly recovered to values close to those found under normoxia. As a consequence of this ability to feed during hypoxia, no difference in soft tissue dry weight (digestive gland not included) was observed at the end of the experimental period between oxic conditions among fed scallops. However, shell growth was negatively affected by hypoxic condition. Starved individuals exhibited similar weight loss between hypoxic and normoxic conditions indicating no or little effect of oxic condition on maintenance costs. Considering the observed responses for feeding, growth and maintenance, we can hypothesize that this species presents metabolic/bioenergetic efficient adaptations to deal with hypoxic conditions that are recurrent in Peruvian coastal bays. We hypothesize that the small observed effects might be modelled in the context of the Dynamic Energy Budget theory as a restriction of reserve mobilization under hypoxic conditions.

  16. Nutritional modulation of IGF-1 in relation to growth and body condition in Sceloporus lizards.

    Science.gov (United States)

    Duncan, Christine A; Jetzt, Amanda E; Cohick, Wendie S; John-Alder, Henry B

    2015-05-15

    Nutrition and energy balance are important regulators of growth and the growth hormone/insulin-like growth factor (GH/IGF) axis. However, our understanding of these functions does not extend uniformly to all classes of vertebrates and is mainly limited to controlled laboratory conditions. Lizards can be useful models to improve our understanding of the nutritional regulation of the GH/IGF-1 axis because many species are relatively easy to observe and manipulate both in the laboratory and in the field. In the present study, the effects of variation in food intake on growth, body condition, and hepatic IGF-1 mRNA levels were measured in (1) juveniles of Sceloporus jarrovii maintained on a full or 1/3 ration and (2) hatchlings of Sceloporus undulatus subjected to full or zero ration with or without re-feeding. These parameters plus plasma IGF-1 were measured in a third experiment using adults of S. undulatus subjected to full or zero ration with or without re-feeding. In all experiments, plasma corticosterone was measured as an anticipated indicator of nutritional stress. In S. jarrovii, growth and body condition were reduced but lizards remained in positive energy balance on 1/3 ration, and hepatic IGF-1 mRNA and plasma corticosterone were not affected in comparison to full ration. In S. undulatus, growth, body condition, hepatic IGF-1 mRNA, and plasma IGF-1 were all reduced by zero ration and restored by refeeding. Plasma corticosterone was increased in response to zero ration and restored by full ration in hatchlings but not adults of S. undulatus. These data indicate that lizards conform to the broader vertebrate model in which severe food deprivation and negative energy balance is required to attenuate systemic IGF-1 expression. However, when animals remain in positive energy balance, reduced food intake does not appear to affect systemic IGF-1. Consistent with other studies on lizards, the corticosterone response to reduced food intake is an unreliable indicator

  17. Influence of bovine lactoferrin on the growth of selected probiotic bacteria under aerobic conditions.

    Science.gov (United States)

    Chen, Po-Wen; Ku, Yu-We; Chu, Fang-Yi

    2014-10-01

    Bovine lactoferrin (bLf) is a natural glycoprotein, and it shows broad-spectrum antimicrobial activity. However, reports on the influences of bLf on probiotic bacteria have been mixed. We examined the effects of apo-bLf (between 0.25 and 128 mg/mL) on both aerobic and anaerobic cultures of probiotics. We found that bLf had similar effects on the growth of probiotics under aerobic or anaerobic conditions, and that it actively and significantly (at concentrations of >0.25 mg/mL) retarded the growth rate of Bifidobacterium bifidum (ATCC 29521), B. longum (ATCC 15707), B. lactis (BCRC 17394), B. infantis (ATCC 15697), Lactobacillus reuteri (ATCC 23272), L. rhamnosus (ATCC 53103), and L. coryniformis (ATCC 25602) in a dose-dependent manner. Otherwise, minimal inhibitory concentrations (MICs) were 128 or >128 mg/mL against B. bifidum, B. longum, B. lactis, L. reuteri, and L. rhamnosus (ATCC 53103). With regard to MICs, bLf showed at least four-fold lower inhibitory effect on probiotics than on pathogens. Intriguingly, bLf (>0.25 mg/mL) significantly enhanced the growth of Rhamnosus (ATCC 7469) and L. acidophilus (BCRC 14065) by approximately 40-200 %, during their late periods of growth. Supernatants produced from aerobic but not anaerobic cultures of L. acidophilus reduced the growth of Escherichia coli by about 20 %. Thus, bLf displayed a dose-dependent inhibitory effect on the growth of most probiotic strains under either aerobic or anaerobic conditions. An antibacterial supernatant prepared from the aerobic cultures may have significant practical use.

  18. Optimization of induction, subculture conditions, and growth kinetics of Angelica sinensis (Oliv.) Diels callus.

    Science.gov (United States)

    Huang, Bing; Han, Lijuan; Li, Shaomei; Yan, Chunyan

    2015-01-01

    Angelica sinensis (Oliv.) Diels is an important traditional Chinese medicine, and the medicinal position is its root. This perennial herb grows vigorously only in specific areas and the environment. Tissue culture induction of callus and plant regeneration is an important and effective way to obtain large scale cultures of A. sinensis. The objective was to optimize the inductive, subculture conditions, and growth kinetics of A. sinensis. Tissue culture conditions for A. sinensis were optimized using leaves and petioles (types I and II) as explants source. Murashige and Skoog (MS) and H media supplemented with 30 g/L sucrose, 7.5 g/L agar, and varying concentrations of plant growth regulators were used for callus induction. In addition, four different basal media supplemented with 1.0 mg/L 2,4-dichlorophenoxy acetic acid (2,4-D), 0.2 mg/L 6-benzyladenine (BA) and 30 g/L sucrose were optimized for callus subculture. Finally, growth kinetics of A. sinensis cultured on different subculture media was investigated based on callus properties, including fresh weight, dry weight, medium pH, callus relative fresh weight growth, callus relative growth rate (CRGR), and sucrose content. MS medium supplemented with 5 mg/L α-naphthaleneacetic acid, 0.5 mg/L BA, 0.7 mg/L 2,4-D, 30 g/L sucrose and 7.5 g/L agar resulted in optimal callus induction in A. sinensis while petiole I was found as the best plant organ for callus induction. The B5 medium supplemented with 1.0 mg/L 2,4-D, 0.2 mg/L BA and 30 g/L sucrose displayed the best results in A. sinensis callus subculture assays. The optimized conditions could be one of the most potent methods for large-scale tissue culture of A. sinensis.

  19. Modification of growth conditions by mm-waves of wood-decaying mushrooms cultures

    International Nuclear Information System (INIS)

    Avagyan, I.A.

    2016-01-01

    Basidial macromycetes are not only value food, but can be used as source of such biological active compounds as the genistein, β -glucans, glioxal-oxidase et al. In this work we used different frequencies of extremely high frequency of electromagnetic irradiation (EHF EMI) with the aim of obtaining mushroom cultures with increased fermentative activity by the modulation of its growth conditions during growth on the peptone media. We investigated the influence of the non-thermal extremely high frequency electromagnetic waves in the interval of 45-53 GHz on β-glucosidase activities of two species of wood-decaying mushroom. In this study we examined the most popular edible wood-decaying mushroom Pleurotus ostreatus, which is wide-spread in the forests and commercial mushroom Lentinula edodes, under influence of such an abiotic factor as the extremely high frequency waves in the interval of 45 GHz - 53 GHz during 20 and 40 min on the 7th day of mycelial culture's growth. After the treatment of cultures we continued their growth and on the 3th day we examined the influence of these waves on fermentative activity of mycelial extracts. The some conditions of such treatment led to significant rising of β-glucosidase activities in the extracts of mycelial cultures

  20. Initial growth of Costus longebracteolatus and Costus spiralis ‘French Kiss’ under different light conditions

    Directory of Open Access Journals (Sweden)

    Renata Bachin Mazzini-Guedes

    2016-12-01

    Full Text Available The Brazilian native Costus longebracteolatus and Costus spiralis ‘French Kiss’, in the family Costaceae, have been used as both cut flowers and cut foliage. It is known that Costus species grow better under partial shade, but studies on the influence of shading or light on plant growth, development, and flower production are still incipient. As this kind of information is essential on planning of planting, production, and agribusiness activities, the objective of this research was to evaluate the influence of different colored shade nets and light conditions on the initial growth of both C. longebracteolatus and C. spiralis ‘French Kiss’. Plants, obtained from cuttings of pseudostems, were cultivated under six light conditions, which comprised six treatments, along 270 days: red net with 50% shading, blue net with 50% shading, black net with 70% shading, black net with 50% shading, black net with 30% shading, and full sun. The initial growth of C. longebracteolatus (up to 270 days is more successful under the blue net with 50% shading, which promoted highest values of pseudostem length and dry matter of aerial part. For C. spiralis ‘French Kiss’ plants, both the red and blue nets with 50% shading implied best results and differed for the other treatments with greater pseudostem length. Plant exposure to full sun inhibited growth and development, and favored early leaf necrosis.

  1. Increased biomass yield of Lactococcus lactis during energetically limited growth and respiratory conditions

    DEFF Research Database (Denmark)

    Købmann, Brian Jensen; Blank, Lars Mathias; Solem, Christian

    2008-01-01

    (glucose/mannose-specific phosphotransferase system). Amino acid catabolism could be excluded as the source of the additional ATP. Since mutants without a functional H+-ATPase produced less ATP under sugar starvation and respiratory conditions, the additional ATP yield appears to come partly from energy......Lactococcus lactis is known to be capable of respiration under aerobic conditions in the presence of haemin. In the present study the effect of respiration on ATP production during growth on different sugars was examined. With glucose as the sole carbon source, respiratory conditions in L. lactis...... MG1363 resulted in only a minor increase, 21%, in biomass yield. Since ATP production through substrate-level phosphorylation was essentially identical with and without respiration, the increased biomass yield was a result of energy-saving under respiratory conditions estimated to be 0.4 mol of ATP...

  2. Effect of Bacillus Species Rhizobacteria on Kabuli Chickpea Plants Growth under Pots and Field Conditions

    OpenAIRE

    Ait Kaki, Asma; Benhassine, Sara; Milet, Asma; Kara Ali, Monira; Moula, Nassim; Kacem Chaouche, Nordine

    2018-01-01

    In the present research, some Bacillus strains were produced at the industrial scale in order to be tested on chickpea growth, under pots and field conditions. Bacteria reached high sporulation yields ranging from 0.8×109-2.5×109 and 8×109-10×109 spores mL-1 in flasks and 500 L bioreactor culture conditions, respectively. Under pots experiment, B. amyloliquefaciens (9SRTS) and B. amyloliquefaciens (CWBI) increased significantly the root mass (0.31 and 0.37 vs. 0.066 g, respectively) and reduc...

  3. Rate-Independent Processes with Linear Growth Energies and Time-Dependent Boundary Conditions

    Czech Academy of Sciences Publication Activity Database

    Kružík, Martin; Zimmer, J.

    2012-01-01

    Roč. 5, č. 3 (2012), s. 591-604 ISSN 1937-1632 R&D Projects: GA AV ČR IAA100750802 Grant - others:GA ČR(CZ) GAP201/10/0357 Institutional research plan: CEZ:AV0Z10750506 Keywords : concentrations * oscillations * time - dependent boundary conditions * rate-independent evolution Subject RIV: BA - General Mathematics http://library.utia.cas.cz/separaty/2011/MTR/kruzik-rate-independent processes with linear growth energies and time - dependent boundary conditions.pdf

  4. Modelling growth of Penicillium expansum and Aspergillus niger at constant and fluctuating temperature conditions.

    Science.gov (United States)

    Gougouli, Maria; Koutsoumanis, Konstantinos P

    2010-06-15

    The growth of Penicillium expansum and Aspergillus niger, isolated from yogurt production environment, was investigated on malt extract agar with pH=4.2 and a(w)=0.997, simulating yogurt, at isothermal conditions ranging from -1.3 to 35 degrees C and from 5 to 42.3 degrees C, respectively. The growth rate (mu) and (apparent) lag time (lambda) of the mycelium growth were modelled as a function of temperature using a Cardinal Model with Inflection (CMI). The results showed that the CMI can describe successfully the effect of temperature on fungal growth within the entire biokinetic range for both isolates. The estimated values of the CMI for mu were T(min)=-5.74 degrees C, T(max)=30.97 degrees C, T(opt)=22.08 degrees C and mu(opt)=0.221 mm/h for P. expansum and T(min)=10.13 degrees C, T(max)=43.13 degrees C, T(opt)=31.44 degrees C, and mu(opt)=0.840 mm/h for A. niger. The cardinal values for lambda were very close to the respective values for mu indicating similar temperature dependence of the growth rate and the lag time of the mycelium growth. The developed models were further validated under fluctuating temperature conditions using various dynamic temperature scenarios. The time-temperature conditions studied included single temperature shifts before or after the end of the lag time and continuous periodic temperature fluctuations. The prediction of growth at changing temperature was based on the assumption that after a temperature shift the growth rate is adopted instantaneously to the new temperature, while the lag time was predicted using a cumulative lag approach. The results showed that when the temperature shifts occurred before the end of the lag, they did not cause any significant additional lag and the observed total lag was very close to the cumulative lag predicted by the model. In experiments with temperature shifts after the end of the lag time, accurate predictions were obtained when the temperature profile included temperatures which were inside the

  5. Characteristics of bacterial and fungal growth in plastic bottled beverages under a consuming condition model.

    Science.gov (United States)

    Watanabe, Maiko; Ohnishi, Takahiro; Araki, Emiko; Kanda, Takashi; Tomita, Atsuko; Ozawa, Kazuhiro; Goto, Keiichi; Sugiyama, Kanji; Konuma, Hirotaka; Hara-Kudo, Yukiko

    2014-01-01

    Microbial contamination in unfinished beverages can occur when drinking directly from the bottle. Various microorganisms, including foodborne pathogens, are able to grow in these beverages at room temperature or in a refrigerator. In this study, we elucidated the characteristics of microorganism growth in bottled beverages under consuming condition models. Furthermore, we provide insight into the safety of partially consumed bottled beverages with respect to food hygiene. We inoculated microorganisms, including foodborne pathogens, into various plastic bottled beverages and analysed the dynamic growth of microorganisms as well as bacterial toxin production in the beverages. Eight bottled beverage types were tested in this study, namely green tea, apple juice drink, tomato juice, carbonated drink, sport drink, coffee with milk, isotonic water and mineral water, and in these beverages several microorganism types were used: nine bacteria including three toxin producers, three yeasts, and five moulds. Following inoculation, the bottles were incubated at 35°C for 48 h for bacteria, 25°C for 48 h for yeasts, and 25°C for 28 days for moulds. During the incubation period, the number of bacteria and yeasts and visible changes in mould-growth were determined over time. Our results indicated that combinations of the beverage types and microorganism species correlated with the degree of growth. Regarding factors that affect the growth and toxin-productivity of microorganisms in beverages, it is speculated that the pH, static/shaking culture, temperature, additives, or ingredients, such as carbon dioxide or organic matter (especially of plant origin), may be important for microorganism growth in beverages. Our results suggest that various types of unfinished beverages have microorganism growth and can include food borne pathogens and bacterial toxins. Therefore, our results indicate that in terms of food hygiene it is necessary to consume beverages immediately after opening

  6. Growth Responses of Fish During Chronic Exposure of Metal Mixture under Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Saima Naz and Muhammad Javed

    2013-07-01

    Full Text Available Growth responses of five fish species viz. Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix were determined, separately, under chronic exposure of binary mixture of metals (Zn+Ni at sub-lethal concentrations (1/3rd of LC50 for 12 weeks. Randomized complete block design (RCBD was followed to conduct this research work. The groups (10 fish each of Catla catla, Labeo rohita, Cirrhina mrigala, Ctenopharyngodon idella and Hypophthalmichthys molitrix having almost similar weights were investigated for their growth responses and metals bioaccumulation patterns in their body organs during chronic exposure of Zn+Ni mixture. The bioaccumulation of metals in the fish body organs viz. gills, liver, kidney, fins, bones, muscle and skin were also determined before and after growth trails under the stress of metals mixture. The exposure of fish to sub-lethal concentrations of mixture caused significant impacts on the average wet weight increments of five fish species. Ctenopharyngodon idella and Labeo rohita attained significantly higher weights, followed by that of Hypophthalmichthys molitrix, Cirrhina mrigala and Catla catla. However, the growth of metals mixture exposed fish species was significantly lesser than that of control fish (un-stressed. Significantly variable condition factor values reflected the degree of fish well-beings that correlated directly with fish growth and metal exposure concentration. Any significant change in feed intake, due to stress, is reflected in terms of fish growth showing the impacts of metal mixture on fish growth were either additive or antagonist / synergistic. Accumulation of all the metals in fish body followed the general order: liver>kidney>gills> skin >muscle> fins >bones.

  7. Controlled growth of CNT in mesoporous AAO through optimized conditions for membrane preparation and CVD operation

    Energy Technology Data Exchange (ETDEWEB)

    Ciambelli, P; Sarno, M; Leone, C; Sannino, D [Department of Chemical and Food Engineering, University of Salerno, I-84084 Fisciano (Italy); Arurault, L; Fontorbes, S; Datas, L; Lenormand, P; Le Blond Du Plouy, S, E-mail: msarno@unisa.it, E-mail: arurault@chimie.ups-tlse.fr [Universite de Toulouse, CIRIMAT, UPS/INPT/CNRS, LCMIE, F-31062 Toulouse Cedex 9 (France)

    2011-07-01

    Anodic aluminium oxide (RAAO) membranes with a mesoporous structure were prepared under strictly controlling experimental process conditions, and physically and chemically characterized by a wide range of experimental techniques. Commercial anodic aluminium oxide (CAAO) membranes were also investigated for comparison. We demonstrated that RAAO membranes have lower content of both water and phosphorus and showed better porosity shape than CAAO. The RAAO membranes were used for template growth of carbon nanotubes (CNT) inside its pores by ethylene chemical vapour deposition (CVD) in the absence of a catalyst. A composite material, containing one nanotube for each channel, having the same length as the membrane thickness and an external diameter close to the diameter of the membrane holes, was obtained. Yield, selectivity and quality of CNTs in terms of diameter, length and arrangement (i.e. number of tubes for each channel) were optimized by investigating the effect of changing the experimental conditions for the CVD process. We showed that upon thermal treatment RAAO membranes were made up of crystallized allotropic alumina phases, which govern the subsequent CNT growth, because of their catalytic activity, likely due to their Lewis acidity. The strict control of experimental conditions for membrane preparation and CNT growth allowed us to enhance the carbon structural order, which is a critical requisite for CNT application as a substitute for copper in novel nano-interconnects.

  8. Growth, photosynthetic pigments and production of essential oil of long-pepper under different light conditions.

    Science.gov (United States)

    Lima, Vandimilli A; Pacheco, Fernanda V; Avelar, Rafaella P; Alvarenga, Ivan C A; Pinto, José Eduardo B P; Alvarenga, Amauri A DE

    2017-01-01

    Piper hispidinervum C. DC. is popularly known as long-pepper and it owns a commercial value due to the essential oil it produces. Long-pepper oil is rich in safrole and eugenoln components that have insecticidal, fungicidal and bactericidal activity. It has been establish that to medicinal plants light influences not only growth but also essential oil production. The growth, the content of photosynthetic pigments and the essential oil production of Piper hispidinervum at greenhouses with different light conditions was evaluated. The treatments were characterized by cultivation of plants for 180 days under different light conditions, produced by shading greenhouses with 50% and 30% of natural incident irradiance, two colored shading nets red (RN) and blue (BN) both blocking 50% of the incident radiation and one treatment at full-sun (0% of shade). The results showed that the treatments of 50% shade and RN and BN were the ones which stimulated the greater growth. Blue and red light also had the best production of photosynthetic pigments. Essential oil yielded more under full sun therefore this is the most indicated condition to produce seedlings for the chemical and pharmaceutical industry.

  9. Growth, photosynthetic pigments and production of essential oil of long-pepper under different light conditions

    Directory of Open Access Journals (Sweden)

    VANDIMILLI A. LIMA

    Full Text Available ABSTRACT Piper hispidinervum C. DC. is popularly known as long-pepper and it owns a commercial value due to the essential oil it produces. Long-pepper oil is rich in safrole and eugenoln components that have insecticidal, fungicidal and bactericidal activity. It has been establish that to medicinal plants light influences not only growth but also essential oil production. The growth, the content of photosynthetic pigments and the essential oil production of Piper hispidinervum at greenhouses with different light conditions was evaluated. The treatments were characterized by cultivation of plants for 180 days under different light conditions, produced by shading greenhouses with 50% and 30% of natural incident irradiance, two colored shading nets red (RN and blue (BN both blocking 50% of the incident radiation and one treatment at full-sun (0% of shade. The results showed that the treatments of 50% shade and RN and BN were the ones which stimulated the greater growth. Blue and red light also had the best production of photosynthetic pigments. Essential oil yielded more under full sun therefore this is the most indicated condition to produce seedlings for the chemical and pharmaceutical industry.

  10. Arabidopsis Phosphatidic Acid Phosphohydrolases Are Essential for Growth under Nitrogen-Depleted Conditions

    Directory of Open Access Journals (Sweden)

    Yushi Yoshitake

    2017-10-01

    Full Text Available The Arabidopsis homologs of mammalian lipin, PAH1 and PAH2, are cytosolic phosphatidic acid phosphohydrolases that are involved in phospholipid biosynthesis and are essential for growth under phosphate starvation. Here, pah1 pah2 double-knockout mutants were found to be hypersensitive to nitrogen (N starvation, whereas transgenic plants overexpressing PAH1 or PAH2 in the pah1 pah2 mutant background showed a similar growth phenotype as compared with wild type (WT under N starvation. The chlorophyll content of pah1 pah2 was significantly lower than that of WT, whereas the chlorophyll content and photosynthetic activity of the transgenic plants were significantly higher than those of WT under N-depleted conditions. Membrane glycerolipid composition of the pah1 pah2 mutants showed a significant decrease in the mole percent of chloroplast lipids to other phospholipids, whereas membrane lipid composition did not differ between transgenic plants and WT plants. Pulse-chase labeling experiments using plants grown under N-depleted conditions showed that, in pah1 pah2 plants, the labeling percent of chloroplast lipids such as phosphatidylglycerol and monogalactosyldiacylglycerol in the total glycerolipids was significantly lower than in WT. Moreover, N starvation-induced degradation of chloroplast structure was enhanced in pah1 pah2 mutants, and the membrane structure was recovered by complementation with PAH1. Thus, PAH is involved in maintaining chloroplast membrane structure and is required for growth under N-depleted conditions.

  11. A portable anaerobic microbioreactor reveals optimum growth conditions for the methanogen Methanosaeta concilii.

    Science.gov (United States)

    Steinhaus, Benjamin; Garcia, Marcelo L; Shen, Amy Q; Angenent, Largus T

    2007-03-01

    Conventional studies of the optimum growth conditions for methanogens (methane-producing, obligate anaerobic archaea) are typically conducted with serum bottles or bioreactors. The use of microfluidics to culture methanogens allows direct microscopic observations of the time-integrated response of growth. Here, we developed a microbioreactor (microBR) with approximately 1-microl microchannels to study some optimum growth conditions for the methanogen Methanosaeta concilii. The microBR is contained in an anaerobic chamber specifically designed to place it directly onto an inverted light microscope stage while maintaining a N2-CO2 environment. The methanogen was cultured for months inside microchannels of different widths. Channel width was manipulated to create various fluid velocities, allowing the direct study of the behavior and responses of M. concilii to various shear stresses and revealing an optimum shear level of approximately 20 to 35 microPa. Gradients in a single microchannel were then used to find an optimum pH level of 7.6 and an optimum total NH4-N concentration of less than 1,100 mg/liter (<47 mg/liter as free NH3-N) for M. concilii under conditions of the previously determined ideal shear stress and pH and at a temperature of 35 degrees C.

  12. Initial growth of Bauhinia variegata trees under different colored shade nets and light conditions

    Directory of Open Access Journals (Sweden)

    Renata Bachin Mazzini-Guedes

    2014-12-01

    Full Text Available Bauhinia variegata and B. variegata var. candida, commonly known as orchid trees, are small sized trees widely used for urban forestry and landscaping. Adult plants grow under full sun; in Brazil, however, seedlings are generally cultivated in commercial nurseries under natural half-shading. The objective of this study was to evaluate the influence of different colored shade nets and light conditions on the initial growth of B. variegata and B. variegata var. candida. The influence of six light conditions (red net with 50% shading; blue net with 50% shading; black net with 70% shading; black net with 50% shading; black net with 30% shading; and full sun on the initial growth of B. variegata and B. variegata var. candida were evaluated along 160 days, and growth relationships were calculated. Seedlings showed more efficiency on the use of photoassimilated compounds when grown under full sun. Such condition is the most appropriate for seedling production of B. variegata and B. variegata var. candida, contradicting what has been performed in practice.

  13. Growth condition dependency is the major cause of non-responsiveness upon genetic perturbation.

    Directory of Open Access Journals (Sweden)

    Saman Amini

    Full Text Available Investigating the role and interplay between individual proteins in biological processes is often performed by assessing the functional consequences of gene inactivation or removal. Depending on the sensitivity of the assay used for determining phenotype, between 66% (growth and 53% (gene expression of Saccharomyces cerevisiae gene deletion strains show no defect when analyzed under a single condition. Although it is well known that this non-responsive behavior is caused by different types of redundancy mechanisms or by growth condition/cell type dependency, it is not known what the relative contribution of these different causes is. Understanding the underlying causes of and their relative contribution to non-responsive behavior upon genetic perturbation is extremely important for designing efficient strategies aimed at elucidating gene function and unraveling complex cellular systems. Here, we provide a systematic classification of the underlying causes of and their relative contribution to non-responsive behavior upon gene deletion. The overall contribution of redundancy to non-responsive behavior is estimated at 29%, of which approximately 17% is due to homology-based redundancy and 12% is due to pathway-based redundancy. The major determinant of non-responsiveness is condition dependency (71%. For approximately 14% of protein complexes, just-in-time assembly can be put forward as a potential mechanistic explanation for how proteins can be regulated in a condition dependent manner. Taken together, the results underscore the large contribution of growth condition requirement to non-responsive behavior, which needs to be taken into account for strategies aimed at determining gene function. The classification provided here, can also be further harnessed in systematic analyses of complex cellular systems.

  14. Reprocessing of nonoptimally exposed holograms

    International Nuclear Information System (INIS)

    Phipps, G.S.; Robertson, C.E.; Tamashiro, F.M.

    1980-01-01

    Two reprocessing techniques have been investigated that are capable of correcting the effects of nonoptimum optical density of photographic amplitude holograms recorded on Agfa-Gevaert type 10E75 plates. In some cases a reprocessed hologram will exhibit a diffraction efficiency even higher than that obtainable from a hologram exposed and processed to the optimum density. The SNR of the reprocessed holograms is much higher than that of the same holograms belached with cupric bromide. In some cases the SNR approaches the optimum value for a properly exposed amplitude hologram. Subjective image quality and resolution of reprocessed hologram reconstructins appear to be no different than for normal single-development holograms. Repeated reprocessing is feasible and in some cases desirable as a means of increasing diffraction efficiency

  15. Mathematical modeling of growth of Salmonella in raw ground beef under isothermal conditions from 10 to 45 Degree C

    Science.gov (United States)

    The objective of this study was to develop primary and secondary models to describe the growth of Salmonella in raw ground beef. Primary and secondary models can be integrated into a dynamic model that can predict the microbial growth under varying environmental conditions. Growth data of Salmonel...

  16. Winter feeding, growth and condition of brown trout Salmo trutta in a groundwater-dominated stream

    Science.gov (United States)

    French, William E.; Vondracek, Bruce C.; Ferrington, Leonard C.; Finlay, Jacques C.; Dieterman, Douglas J.

    2014-01-01

    Winter can be a stressful period for stream-dwelling salmonid populations, often resulting in reduced growth and survival. Stream water temperatures have been identified as a primary mechanism driving reductions in fitness during winter. However, groundwater inputs can moderate water temperature and may reduce winter severity. Additionally, seasonal reductions in prey availability may contribute to decreased growth and survival, although few studies have examined food webs supporting salmonids under winter conditions. This study employed diet, stable isotope, and mark-recapture techniques to examine winter (November through March) feeding, growth, and condition of brown troutSalmo trutta in a groundwater-dominated stream (Badger Creek, Minnesota, USA). Growth was greater for fish ≤ 150 mm (mean = 4.1 mg g−1 day−1) than for those 151–276 mm (mean = 1.0 mg g−1 day−1) during the winter season. Overall condition from early winter to late winter did not vary for fish ≤150 mm (mean relative weight (Wr) = 89.5) and increased for those 151–276 mm (mean Wr = 85.8 early and 89.4 late). Although composition varied both temporally and by individual, brown trout diets were dominated by aquatic invertebrates, primarily Amphipods, Dipterans, and Trichopterans. Stable isotope analysis supported the observations of the dominant prey taxa in stomach contents and indicated the winter food web was supported by a combination of allochthonous inputs and aquatic macrophytes. Brown trout in Badger Creek likely benefited from the thermal regime and increased prey abundance present in this groundwater-dominated stream during winter.

  17. Growth trajectories of the human embryonic head and periconceptional maternal conditions.

    Science.gov (United States)

    Koning, I V; Baken, L; Groenenberg, I A L; Husen, S C; Dudink, J; Willemsen, S P; Gijtenbeek, M; Koning, A H J; Reiss, I K M; Steegers, E A P; Steegers-Theunissen, R P M

    2016-05-01

    Can growth trajectories of the human embryonic head be created using 3D ultrasound (3D-US) and virtual reality (VR) technology, and be associated with second trimester fetal head size and periconceptional maternal conditions? Serial first trimester head circumference (HC) and head volume (HV) measurements were used to create reliable growth trajectories of the embryonic head, which were significantly associated with fetal head size and periconceptional maternal smoking, age and ITALIC! in vitro fertilization (IVF)/intra-cytoplasmic sperm injection (ICSI) treatment. Fetal growth is influenced by periconceptional maternal conditions. We selected 149 singleton pregnancies with a live born non-malformed fetus from the Rotterdam periconception cohort. Bi-parietal diameter and occipital frontal diameter to calculate HC, HV and crown-rump length (CRL) were measured weekly between 9 + 0 and 12 + 6 weeks gestational age (GA) using 3D-US and VR. Fetal HC was obtained from second trimester structural anomaly scans. Growth trajectories of the embryonic head were created with general additive models and linear mixed models were used to estimate associations with maternal periconceptional conditions as a function of GA and CRL, respectively. A total of 303 3D-US images of 149 pregnancies were eligible for embryonic head measurements (intra-class correlation coefficients >0.99). Associations were found between embryonic HC and fetal HC ( ITALIC! ρ = 0.617, ITALIC! P head measured by HC and HV (All ITALIC! P head may be of benefit in future early antenatal care. This study was funded by the Department of Obstetrics and Gynaecology, Erasmus MC University Medical Centre and Sophia Foundation for Medical Research, Rotterdam, The Netherlands (SSWO grant number 644). No competing interests are declared. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email

  18. The effect of growth conditions on the seed size/number trade-off.

    Directory of Open Access Journals (Sweden)

    Cloé Paul-Victor

    2009-09-01

    Full Text Available If the amount of resources allocated to reproduction (K is fixed, then an increase in seed mass (S can only be achieved by a decrease in seed number (n = K/S. Thus, log(n = log(K-log(S producing a slope of -1 when seed mass and number are plotted on log-log axes. However, in comparative studies, empirical support for a slope of -1 is limited and contentious, leading some to question the utility of this concept.First, we show that the expected slope depends on whether genotypes and species producing seeds of different mass are expected to reach the same adult size and that this in turn depends partly on the nature of growth. Second, we present experimental results using a population of recombinant inbred lines (RILs of Arabidopsis thaliana. When these RILs are grown in large pots with plentiful nutrients, they exhibit a trade-off between seed size and number with a slope of -1.68 (+/-0.18 on log-log axes. This occurs because of genetic correlations between seed mass and adult size so that, under the right growth conditions, lines producing lighter seeds have the genetic potential to produce larger rosettes and hence a greater total mass of seeds. We re-grew lines in small pots (10 and 40 mm diameter in a nutrient-poor substrate so that final adult size was heavily restricted by pot size.Under our growth conditions, small-seeded lines were unable to produce a greater total mass of seeds. Hence a trade-off emerged between seed mass and seed number with a slope of -1.166+/-0.319 on log-log axes in 40-mm diameter pots (close to the expected value of -1, although the slope was 0.132+/-0.263 in 10-mm diameter pots, demonstrating that the nature of the trade-off is sensitive to the growth conditions.

  19. Effect of ocean acidification on growth and otolith condition of juvenile scup, Stenotomus chrysops.

    Science.gov (United States)

    Perry, Dean M; Redman, Dylan H; Widman, James C; Meseck, Shannon; King, Andrew; Pereira, Jose J

    2015-09-01

    Increasing amounts of atmospheric carbon dioxide (CO2) from human industrial activities are causing changes in global ocean carbonate chemistry, resulting in a reduction in pH, a process termed "ocean acidification." It is important to determine which species are sensitive to elevated levels of CO2 because of potential impacts to ecosystems, marine resources, biodiversity, food webs, populations, and effects on economies. Previous studies with marine fish have documented that exposure to elevated levels of CO2 caused increased growth and larger otoliths in some species. This study was conducted to determine whether the elevated partial pressure of CO2 (pCO2) would have an effect on growth, otolith (ear bone) condition, survival, or the skeleton of juvenile scup, Stenotomus chrysops, a species that supports both important commercial and recreational fisheries. Elevated levels of pCO2 (1200-2600 μatm) had no statistically significant effect on growth, survival, or otolith condition after 8 weeks of rearing. Field data show that in Long Island Sound, where scup spawn, in situ levels of pCO2 are already at levels ranging from 689 to 1828 μatm due to primary productivity, microbial activity, and anthropogenic inputs. These results demonstrate that ocean acidification is not likely to cause adverse effects on the growth and survivability of every species of marine fish. X-ray analysis of the fish revealed a slightly higher incidence of hyperossification in the vertebrae of a few scup from the highest treatments compared to fish from the control treatments. Our results show that juvenile scup are tolerant to increases in seawater pCO2, possibly due to conditions this species encounters in their naturally variable environment and their well-developed pH control mechanisms.

  20. Arsenic uptake, transformation, and release by three freshwater algae under conditions with and without growth stress.

    Science.gov (United States)

    Xie, Shaowen; Liu, Jinxin; Yang, Fen; Feng, Hanxiao; Wei, Chaoyang; Wu, Fengchang

    2018-05-04

    As speciation for the other two algae with Cu 2+ inhibition and all the three algae with isothiazolinone inhibition, corroborating the above hypothesis again. All the algae tested in this study demonstrated great abilities for As transformation and release, as seen by the much higher rates of 86.11-99.98% and 81.11-99.89% for transformation and release when compared to the control, respectively. When inhibitors were added, the transformation and release values of only A. flosaquae decreased remarkably down to 72.37-86.79% and 64.67-85.24%, respectively, while no changes were seen for these values in the other two algae, indicating that growth stress did not affect the As transformation and release of the other algae. The biological productivity of As by the three algae followed the order of M. aeruginosa, Chlorella sp., and A. flosaquae, which was generally consistent with the As transformation and release in conditions with and without inhibitors, suggesting that the As behavior in the algae that was related to growth stress largely differed among algae species.

  1. Effect of mycorrhizas application on plant growth and nutrient uptake in cucumber production under field conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ortas, I.

    2010-07-01

    Mycorrhizas application in horticultural production in the Eastern Mediterranean region of Turkey has been studied under field conditions for several years. The effects of different arbuscular mycorrhizal fungi (AMF) have been evaluated under field conditions for cucumber production. The parameters measured were seedling survival, plant growth and yield, and root colonization. In 1998 and 1999, Glomus mosseae and Glomus etunicatum inoculated cucumber seedlings were treated with and without P (100 kg P2O5 ha-1) application. A second experiment was set up to evaluate the response of cucumber to the inoculation with a consortia of indigenous mycorrhizae, G. mosseae, G. etunicatum, Glomus clarum, Glomus caledonium and a mixture of these four species. Inoculated and control non inoculated cucumber seedlings were established under field conditions in 1998, 2001, 2002 and 2004. Seedling quality, seedling survival under field conditions and yield response to mycorrhiza were tested. Fruits were harvested periodically; at blossom, plant leaves and root samples were taken for nutrient content and mycorrhizal colonization analysis respectively. The field experiment results showed that mycorrhiza inoculation significantly increased cucumber seedling survival, fruit yield, P and Zn shoot concentrations. Indigenous mycorrhiza inoculum was successful in colonizing plant roots and resulted in better plant growth and yield. The relative effectiveness of each of the inocula tested was not consistent in the different experiments, although inoculated plants always grew better than control no inoculated. The most relevant result for growers was the increased survival of seedlings. (Author) 20 refs.

  2. Parental care mitigates carry-over effects of poor early conditions on offspring growth

    Science.gov (United States)

    Auer, Sonya K.; Martin, Thomas E.

    2017-01-01

    Poor developmental conditions can have long-lasting negative effects on offspring phenotypes, but impacts often differ among species. Contrasting responses may reflect disparities in experimental protocols among single-species studies or inherent differences among species in their sensitivity to early conditions and/or ability to mitigate negative impacts. We used a common experimental protocol to assess and compare the role of parental care in mitigating effects of poor early conditions on offspring among 4 sympatric bird species in the wild. We experimentally induced low incubation temperatures and examined effects on embryonic developmental rates, hatching success, nestling growth rates, and parental responses. We examined the generality of these effects across 4 species that differ in their phylogenetic history, breeding ecology, and life histories. We found that cooling led to delayed hatching in all species, but carry-over effects on offspring differed among species. Parents of some but not all species increased their offspring provisioning rates in response to experimental cooling with critical benefits for offspring growth rates. Our study shows for the first time that species exhibit clear differences in the degree to which they are affected by poor early conditions. Observed differences among species demonstrate that parental care is a critical mechanism for mitigating potential negative effects on offspring and suggest that parental responses may be constrained to varying degrees by ecology and life histories.

  3. Computational Fluid Dynamic Simulation of Single Bubble Growth under High-Pressure Pool Boiling Conditions

    Directory of Open Access Journals (Sweden)

    Janani Murallidharan

    2016-08-01

    Full Text Available Component-scale modeling of boiling is predominantly based on the Eulerian–Eulerian two-fluid approach. Within this framework, wall boiling is accounted for via the Rensselaer Polytechnic Institute (RPI model and, within this model, the bubble is characterized using three main parameters: departure diameter (D, nucleation site density (N, and departure frequency (f. Typically, the magnitudes of these three parameters are obtained from empirical correlations. However, in recent years, efforts have been directed toward mechanistic modeling of the boiling process. Of the three parameters mentioned above, the departure diameter (D is least affected by the intrinsic uncertainties of the nucleate boiling process. This feature, along with its prominence within the RPI boiling model, has made it the primary candidate for mechanistic modeling ventures. Mechanistic modeling of D is mostly carried out through solving of force balance equations on the bubble. Forces incorporated in these equations are formulated as functions of the radius of the bubble and have been developed for, and applied to, low-pressure conditions only. Conversely, for high-pressure conditions, no mechanistic information is available regarding the growth rates of bubbles and the forces acting on them. In this study, we use direct numerical simulation coupled with an interface tracking method to simulate bubble growth under high (up to 45 bar pressure, to obtain the kind of mechanistic information required for an RPI-type approach. In this study, we compare the resulting bubble growth rate curves with predictions made with existing experimental data.

  4. Effects of Different Ectomycorrhizal Fungal Inoculates on the Growth of Pinus tabulaeformis Seedlings under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2016-12-01

    Full Text Available The tree species Pinus tabulaeformis Carr. (P. tabulaeformis is commonly planted in China due to its economic and ecological value. In order to identify one or more ectomycorrhizal (ECM fungal species for future P. tabulaeformis afforestation, we investigated the effects of five ECM fungal species: Laccaria laccata, Boletus edulis, Gomphidius viscidus, Suillus grevillei, and Suillus luteus on the growth of P. tabulaeformis seedlings under greenhouse conditions. The growth parameters of P. tabulaeformis seedlings were evaluated 90 days following fungal colonisation. The majority of seedlings were significantly affected by ECM inoculation. Mycorrhizal inoculated seedlings were taller, had more lateral roots, and a greater biomass compared with the non-mycorrhizal (CK seedlings. With the exception of G. viscidus, inoculated seedlings exhibited higher phosphorus, potassium, and nitrogen content compared with the CK seedlings. In addition, ECM colonisation increased the enzymatic activity of catalase, acidic phosphatase, protease, and the urease content in the rhizosphere soil. Our study showed that Laccaria laccata, Suillus grevillei, and Suillus luteus may be useful for improving the growth and cultivation of P. tabulaeformis seedlings. Furthermore, we observed that S. luteus inoculation increased the gas exchange parameters of P. tabulaeformis seedlings under field conditions.

  5. Fatigue-crack growth behavior of Type 347 stainless steels under simulated PWR water conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seokmin; Min, Ki-Deuk; Yoon, Ji-Hyun; Kim, Min-Chul; Lee, Bong-Sang [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Fatigue crack growth rate (FCGR) curve of stainless steel exists in ASME code section XI, but it is still not considering the environmental effects. The longer time nuclear power plant is operated, the more the environmental degradation issues of materials pop up. There are some researches on fatigue crack growth rate of S304 and S316, but researches of FCGR of S347 used in Korea nuclear power plant are insufficient. In this study, the FCGR of S347 stainless steel was evaluated in the PWR high temperature water conditions. The FCGRs of S347 stainless steel under pressurized-water conditions were measured by using compact-tension (CT) specimens at different levels of dissolved oxygen (DO) and frequency. 1. FCGRs of SS347 were slower than that in ASME XI and environmental effect did not occur when frequency was higher than 1Hz. 2. Fatigue crack growth is accelerated by corrosion fatigue and it is more severe when frequency is slower than 0.1Hz. 3. Increase of crack tip opening time increased corrosion fatigue and it deteriorated environmental fatigue properties.

  6. Growth of preexisting abnormal grains in molybdenum under static and dynamic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Noell, Philip J. [Sandia National Laboratories, P.O. Box 5800, Albuquerque, NM 87185-0889 (United States); Worthington, Daniel L. [Verily Life Sciences, 269 E. Grand Ave., South San Francisco, CA 94080, USA (United States); Taleff, Eric M., E-mail: taleff@utexas.edu [The University of Texas at Austin, Department of Mechanical Engineering, 204 East Dean Keeton St., Stop C2200, Austin, TX 78712 (United States)

    2017-04-24

    This investigation compares the growth rates of preexisting abnormal grains under both static and dynamic conditions. Abnormal grains several millimeters in length were produced in two commercial-purity molybdenum (Mo) materials by tensile straining at temperatures from 1923 to 2073 K (1650–1800 °C). This process is termed dynamic abnormal grain growth (DAGG) because it produces abnormal grains during concurrent plastic straining. DAGG creates abnormal grains at much lower temperatures than does static abnormal grain growth (SAGG). Abnormal grains created through DAGG were characterized with their surrounding microstructures and were then subjected to annealing treatments. Only one-third of the preexisting abnormal grains subsequently grew by SAGG. Among these, SAGG occurred only in those specimens that required the largest strains to initiate DAGG when creating the abnormal grain(s). The rates of boundary migration observed for SAGG were approximately two orders of magnitude slower than those for DAGG. When DAGG in one specimen was interrupted by extended static annealing, it did not recur when straining resumed. The dislocation substructure developed during hot deformation, which includes subgrains typical of five-power creep, is critically important to both DAGG and SAGG of preexisting abnormal grains under the conditions examined.

  7. Colonization with Arbuscular Mycorrhizal Fungi Promotes the Growth of Morus alba L. Seedlings under Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Nan Lu

    2015-03-01

    Full Text Available Morus alba L. is an important tree species planted widely in China because of its economic value. In this report, we investigated the influence of two arbuscular mycorrhizal fungal (AMF species, Glomus mosseae and Glomus intraradices, alone and together, on the growth of M. alba L. seedlings under greenhouse conditions. The growth parameters and physiological performance of M. alba L. seedlings were evaluated 90 days after colonization with the fungi. The growth and physiological performance of M. alba L. seedlings were significantly affected by the AMF species. The mycorrhizal seedlings were taller, had longer roots, more leaves and a greater biomass than the non-mycorrhizae-treated seedlings. In addition, the AMF species-inoculated seedlings had increased root activity and a higher chlorophyll content compared to non-inoculated seedlings. Furthermore, AMF species colonization increased the phosphorus and nitrogen contents of the seedlings. In addition, simultaneous root colonization by the two AMF species did not improve the growth of M. alba L. seedlings compared with inoculation with either species alone. Based on these results, these AMF species may be applicable to mulberry seedling cultivation.

  8. Fibril growth kinetics link buffer conditions and topology of 3D collagen I networks.

    Science.gov (United States)

    Kalbitzer, Liv; Pompe, Tilo

    2018-02-01

    Three-dimensional fibrillar networks reconstituted from collagen I are widely used as biomimetic scaffolds for in vitro and in vivo cell studies. Various physicochemical parameters of buffer conditions for in vitro fibril formation are well known, including pH-value, ion concentrations and temperature. However, there is a lack of a detailed understanding of reconstituting well-defined 3D network topologies, which is required to mimic specific properties of the native extracellular matrix. We screened a wide range of relevant physicochemical buffer conditions and characterized the topology of the reconstituted 3D networks in terms of mean pore size and fibril diameter. A congruent analysis of fibril formation kinetics by turbidimetry revealed the adjustment of the lateral growth phase of fibrils by buffer conditions to be key in the determination of pore size and fibril diameter of the networks. Although the kinetics of nucleation and linear growth phase were affected by buffer conditions as well, network topology was independent of those two growth phases. Overall, the results of our study provide necessary insights into how to engineer 3D collagen matrices with an independent control over topology parameters, in order to mimic in vivo tissues in in vitro experiments and tissue engineering applications. The study reports a comprehensive analysis of physicochemical conditions of buffer solutions to reconstitute defined 3D collagen I matrices. By a combined analysis of network topology, i.e., pore size and fibril diameter, and the kinetics of fibril formation we can reveal the dependence of 3D network topology on buffer conditions, such as pH-value, phosphate concentration and sodium chloride content. With those results we are now able to provide engineering strategies to independently tune the topology parameters of widely used 3D collagen scaffolds based on the buffer conditions. By that, we enable the straightforward mimicking of extracellular matrices of in vivo

  9. Effects of enhanced UVB on growth and yield of alfalfa and soybean under field conditions

    International Nuclear Information System (INIS)

    Al-Oudat, M.; Baydon, S.A.; Mohamad, A.

    1998-01-01

    The effects of 20% increase of UVB on growth and yield of alfalfa (Medicago Sativa L.) and two cultivars of soybean (Glycine Max (L.) Mer) under field conditions have been investigated. The increase of UVB dose ranged between 1.746 and 7.112 J/cm 2 during experiment. The results showed that soybean yield decrease by 16% and 31% in A. 3803 and A. 2522 cultivars respectively, under UVB exposure. The dry weight and leaf area were sensitive in the A. 3803 cultivar, while they were tolerant in the A. 2522 cultivar. Alfalfa response to UVB varied during the different stages of growth, whereas the yield was 12% less in the exposed plants. (author)

  10. Growth kinetics of tin oxide nanocrystals in colloidal suspensions under hydrothermal conditions

    International Nuclear Information System (INIS)

    Lee, Eduardo J.H.; Ribeiro, Caue; Longo, Elson; Leite, Edson R.

    2006-01-01

    Colloidal suspensions of tin oxide nanocrystals were synthesized at room temperature by the hydrolysis reaction of tin chloride (II), in an ethanolic solution. The coarsening kinetics of such nanocrystals was studied by submitting the as-prepared suspensions to hydrothermal treatments at temperatures of 100, 150 and 200 deg. C for periods between 60 and 12,000 min. Transmission electron microscopy (TEM) was used to characterize the samples (i.e. distribution of nanocrystal size, average particle radius and morphology). The results show that the usual Ostwald ripening coarsening mechanism does not fit well the experimental data, which is an indicative that this process is not significant for SnO 2 nanocrystals, in the studied experimental conditions. The morphology evolution of the nanocrystals upon hydrothermal treatment indicates that growth by oriented attachment (OA) should be significant. A kinetic model that describes OA growth is successfully applied to fit the data

  11. Growth and bromatologic value of Typha sp. under semi-arid conditions

    Directory of Open Access Journals (Sweden)

    Jorge Messias Leal do Nascimento

    2015-03-01

    Full Text Available Typha sp. plants are rustic and have accelerated development. However, their real growth and potential to animal nutrition are not so well-known. This study aimed to evaluate the shoot biomass production, growth dynamics and chemicalbromatological composition of Typha sp. plants at different cutting heights, under semiarid conditions. A total of four cutting heights (60 cm, 100 cm, 140 cm and 180 cm were evaluated in a complete randomized design, with five replicates. Plants presented similar production of leaf biomass and heart of palm up to 140 cm height, with higher leaf accumulation above this value. Its heart of palm grows up to 112.5 cm and, above this height, only leaf elongation occurs. It is not recommended to cut this plant bellow 140 cm height, otherwise that can affect the pseudo-stem formation (heart of palm, which supports the leaf biomass accumulation.

  12. Evolution PDEs with nonstandard growth conditions existence, uniqueness, localization, blow-up

    CERN Document Server

    Antontsev, Stanislav

    2015-01-01

    This monograph offers the reader a treatment of the theory of evolution PDEs with nonstandard growth conditions. This class includes parabolic and hyperbolic equations with variable or anisotropic nonlinear structure. We develop methods for the study of such equations and present a detailed account of recent results. An overview of other approaches to the study of PDEs of this kind is provided. The presentation is focused on the issues of existence and uniqueness of solutions in appropriate function spaces, and on the study of the specific qualitative properties of solutions, such as localization in space and time, extinction in a finite time and blow-up, or nonexistence of global in time solutions. Special attention is paid to the study of the properties intrinsic to solutions of equations with nonstandard growth.

  13. Effect of growth conditions on microbial activity and iron-sulfide production by Desulfovibrio vulgaris

    International Nuclear Information System (INIS)

    Zhou, Chen; Vannela, Raveender; Hayes, Kim F.; Rittmann, Bruce E.

    2014-01-01

    Highlights: • Extended incubation time to 16 days allowed significant FeS crystallization. • A weakly acidic pH greatly enhanced particle growth of mackinawite. • Microbial metabolism of different donors systematically altered the ambient pH. • Greater sulfide accumulation stimulated mackinawite transformation to greigite. - Abstract: Sulfate-reducing bacteria (SRB) can produce iron sulfide (FeS) solids with mineralogical characteristics that may be beneficial for a variety of biogeochemical applications, such as long-term immobilization of uranium. In this study, the growth and metabolism of Desulfovibrio vulgaris, one of the best-studied SRB species, were comprehensively monitored in batch studies, and the biogenic FeS solids were characterized by X-ray diffraction. Controlling the pH by varying the initial pH, the iron-to-sulfate ratio, or the electron donor – affected the growth of D. vulgaris and strongly influenced the formation and growth of FeS solids. In particular, lower pH (from initial conditions or a decrease caused by less sulfate reduction, FeS precipitation, or using pyruvate as the electron donor) produced larger-sized mackinawite (Fe 1+x S). Greater accumulation of free sulfide, from more sulfate reduction by D. vulgaris, also led to larger-sized mackinawite and particularly stimulated mackinawite transformation to greigite (Fe 3 S 4 ) when the free sulfide concentration was 29.3 mM. Furthermore, sufficient free Fe 2+ led to the additional formation of vivianite [Fe 3 (PO 4 ) 2 ·8(H 2 O)]. Thus, microbially relevant conditions (initial pH, choice of electron donor, and excess or deficiency of sulfide) are tools to generate biogenic FeS solids of different characteristics

  14. Evaluation of growth and flowering potential of rosa hybrida cultivars under Faisalabad climatic conditions

    International Nuclear Information System (INIS)

    Nadeem, M.; Khan, M.A.; Riaz, A.

    2011-01-01

    Exotic cultivars of hybrid roses respond uncertainly to new habitat. It is necessary to explore the potential of the introduced cultivars to judge the suitability in a new habitat. In the present study, nine Rosa hybrida cultivars including Autumn Sunset, Ice Berg, Paradise, Angel Face, Louise Odier, Casino, Grand Margina, Handel and Gruss-an-Teplitz were evaluated for growth and yield attributed under the climatic conditions of Faisalabad. Results indicated that there was decreasing trend in the growth and flowering of the bushes as the temperature increased above 32 degree C and humidity decreased to 29 %. Number of flowers per bush and diameter of flower decreased as the temperature increased and humidity decreased in contrast to increment in height of the plant and num ber of primary branches per plant in succeeding months. Interaction between yield traits and months was also significant. Overall, significant variations were observed in each cultivar for length and number of petals per flower, number of prickles, fragrance, flower persistence life and color, bush shape and overall performance with respect to climatic conditions of Faisalabad. It is concluded that the cultivars 'Autumn Sunset' and Gruss-an-Teplitz performed better in climatic conditions of Faisalabad. (author)

  15. Human conditions of insulin-like growth factor-I (IGF-I) deficiency

    Science.gov (United States)

    2012-01-01

    Insulin-like growth factor I (IGF-I) is a polypeptide hormone produced mainly by the liver in response to the endocrine GH stimulus, but it is also secreted by multiple tissues for autocrine/paracrine purposes. IGF-I is partly responsible for systemic GH activities although it possesses a wide number of own properties (anabolic, antioxidant, anti-inflammatory and cytoprotective actions). IGF-I is a closely regulated hormone. Consequently, its logical therapeutical applications seems to be limited to restore physiological circulating levels in order to recover the clinical consequences of IGF-I deficiency, conditions where, despite continuous discrepancies, IGF-I treatment has never been related to oncogenesis. Currently the best characterized conditions of IGF-I deficiency are Laron Syndrome, in children; liver cirrhosis, in adults; aging including age-related-cardiovascular and neurological diseases; and more recently, intrauterine growth restriction. The aim of this review is to summarize the increasing list of roles of IGF-I, both in physiological and pathological conditions, underlying that its potential therapeutical options seem to be limited to those proven states of local or systemic IGF-I deficiency as a replacement treatment, rather than increasing its level upper the normal range. PMID:23148873

  16. Optimizing pentacene thin-film transistor performance: Temperature and surface condition induced layer growth modification.

    Science.gov (United States)

    Lassnig, R; Hollerer, M; Striedinger, B; Fian, A; Stadlober, B; Winkler, A

    2015-11-01

    In this work we present in situ electrical and surface analytical, as well as ex situ atomic force microscopy (AFM) studies on temperature and surface condition induced pentacene layer growth modifications, leading to the selection of optimized deposition conditions and entailing performance improvements. We prepared p ++ -silicon/silicon dioxide bottom-gate, gold bottom-contact transistor samples and evaluated the pentacene layer growth for three different surface conditions (sputtered, sputtered + carbon and unsputtered + carbon) at sample temperatures during deposition of 200 K, 300 K and 350 K. The AFM investigations focused on the gold contacts, the silicon dioxide channel region and the highly critical transition area. Evaluations of coverage dependent saturation mobilities, threshold voltages and corresponding AFM analysis were able to confirm that the first 3-4 full monolayers contribute to the majority of charge transport within the channel region. At high temperatures and on sputtered surfaces uniform layer formation in the contact-channel transition area is limited by dewetting, leading to the formation of trenches and the partial development of double layer islands within the channel region instead of full wetting layers. By combining the advantages of an initial high temperature deposition (well-ordered islands in the channel) and a subsequent low temperature deposition (continuous film formation for low contact resistance) we were able to prepare very thin (8 ML) pentacene transistors of comparably high mobility.

  17. Human conditions of insulin-like growth factor-I (IGF-I deficiency

    Directory of Open Access Journals (Sweden)

    Puche Juan E

    2012-11-01

    Full Text Available Abstract Insulin-like growth factor I (IGF-I is a polypeptide hormone produced mainly by the liver in response to the endocrine GH stimulus, but it is also secreted by multiple tissues for autocrine/paracrine purposes. IGF-I is partly responsible for systemic GH activities although it possesses a wide number of own properties (anabolic, antioxidant, anti-inflammatory and cytoprotective actions. IGF-I is a closely regulated hormone. Consequently, its logical therapeutical applications seems to be limited to restore physiological circulating levels in order to recover the clinical consequences of IGF-I deficiency, conditions where, despite continuous discrepancies, IGF-I treatment has never been related to oncogenesis. Currently the best characterized conditions of IGF-I deficiency are Laron Syndrome, in children; liver cirrhosis, in adults; aging including age-related-cardiovascular and neurological diseases; and more recently, intrauterine growth restriction. The aim of this review is to summarize the increasing list of roles of IGF-I, both in physiological and pathological conditions, underlying that its potential therapeutical options seem to be limited to those proven states of local or systemic IGF-I deficiency as a replacement treatment, rather than increasing its level upper the normal range.

  18. Genetic Adaptation to Growth Under Laboratory Conditions in Escherichia coli and Salmonella enterica

    Directory of Open Access Journals (Sweden)

    Anna Knöppel

    2018-04-01

    Full Text Available Experimental evolution under controlled laboratory conditions is becoming increasingly important to address various evolutionary questions, including, for example, the dynamics and mechanisms of genetic adaptation to different growth and stress conditions. In such experiments, mutations typically appear that increase the fitness under the conditions tested (medium adaptation, but that are not necessarily of interest for the specific research question. Here, we have identified mutations that appeared during serial passage of E. coli and S. enterica in four different and commonly used laboratory media and measured the relative competitive fitness and maximum growth rate of 111 genetically re-constituted strains, carrying different single and multiple mutations. Little overlap was found between the mutations that were selected in the two species and the different media, implying that adaptation occurs via different genetic pathways. Furthermore, we show that commonly occurring adaptive mutations can generate undesired genetic variation in a population and reduce the accuracy of competition experiments. However, by introducing media adaptation mutations with large effects into the parental strain that was used for the evolution experiment, the variation (standard deviation was decreased 10-fold, and it was possible to measure fitness differences between two competitors as small as |s| < 0.001.

  19. Growth conditions of 0-group plaice Pleuronectes platessa in the western Wadden Sea as revealed by otolith microstructure analysis

    Science.gov (United States)

    Cardoso, Joana F. M. F.; Freitas, Vânia; de Paoli, Hélène; Witte, Johannes IJ.; van der Veer, Henk W.

    2016-05-01

    Growth studies based on population-based growth estimates are limited by the fact that they do not take into account differences in age/size structure within the population. To overcome these problems, otolith microstructure analysis is often used to estimate individual growth. Here, we analyse growth of 0-group plaice in the western Wadden Sea in two years: a year preceded by a mild winter (1995) and a year preceded by a severe winter (1996). Growth was analysed by combining information on individual growth based on otolith analysis with predictions of maximum growth (= under optimal food conditions) based on a Dynamic Energy Budget model. Otolith analysis revealed that settlement occurred earlier in 1995 than in 1996. In both years, one main cohort was found, followed by a group of late settlers. No differences in mean length-at-age were found between these groups. DEB modelling suggested that growth was not maximal during the whole growing season: realized growth (the fraction of maximum growth realized by 0-group plaice) declined in the summer, although this decline was relatively small. In addition, late settling individuals exhibited lower realized growth than individuals from the main cohort. This study confirms that growth conditions for 0-group plaice are not optimal and that a growth reduction occurs in summer, as suggested in previous studies.

  20. Selecting Native Arbuscular Mycorrhizal Fungi to Promote Cassava Growth and Increase Yield under Field Conditions

    Science.gov (United States)

    Séry, D. Jean-Marc; Kouadjo, Z. G. Claude; Voko, B. R. Rodrigue; Zézé, Adolphe

    2016-01-01

    The use of arbuscular mycorrhizal fungal (AMF) inoculation in sustainable agriculture is now widespread worldwide. Although the use of inoculants consisting of native AMF is highly recommended as an alternative to commercial ones, there is no strategy to allow the selection of efficient fungal species from natural communities. The objective of this study was (i) to select efficient native AMF species (ii) evaluate their impact on nematode and water stresses, and (iii) evaluate their impact on cassava yield, an important food security crop in tropical and subtropical regions. Firstly, native AMF communities associated with cassava rhizospheres in fields were collected from different areas and 7 AMF species were selected, based upon their ubiquity and abundance. Using these criteria, two morphotypes (LBVM01 and LBVM02) out of the seven AMF species selected were persistently dominant when cassava was used as a trap plant. LBVM01 and LBVM02 were identified as Acaulospora colombiana (most abundant) and Ambispora appendicula, respectively, after phylogenetic analyses of LSU-ITS-SSU PCR amplified products. Secondly, the potential of these two native AMF species to promote growth and enhance tolerance to root-knot nematode and water stresses of cassava (Yavo variety) was evaluated using single and dual inoculation in greenhouse conditions. Of the two AMF species, it was shown that A. colombiana significantly improved the growth of the cassava and enhanced tolerance to water stress. However, both A. colombiana and A. appendicula conferred bioprotective effects to cassava plants against the nematode Meloidogyne spp., ranging from resistance (suppression or reduction of the nematode reproduction) or tolerance (low or no suppression in cassava growth). Thirdly, the potential of these selected native AMF to improve cassava growth and yield was evaluated under field conditions, compared to a commercial inoculant. In these conditions, the A. colombiana single inoculation and the

  1. Comparison of Two Mechanistic Microbial Growth Models to Estimate Shelf Life of Perishable Food Package under Dynamic Temperature Conditions

    Directory of Open Access Journals (Sweden)

    Dong Sun Lee

    2014-01-01

    Full Text Available Two mechanistic microbial growth models (Huang’s model and model of Baranyi and Roberts given in differential and integrated equation forms were compared in predicting the microbial growth and shelf life under dynamic temperature storage and distribution conditions. Literatures consistently reporting the microbial growth data under constant and changing temperature conditions were selected to obtain the primary model parameters, set up the secondary models, and apply them to predict the microbial growth and shelf life under fluctuating temperatures. When evaluated by general estimation behavior, bias factor, accuracy factor, and root-mean-square error, Huang’s model was comparable to Baranyi and Roberts’ model in the capability to estimate microbial growth under dynamic temperature conditions. Its simple form of single differential equation incorporating directly the growth rate and lag time may work as an advantage to be used in online shelf life estimation by using the electronic device.

  2. Features of Scots pine radial growth in conditions of provenance trial.

    Science.gov (United States)

    Kuzmin, Sergey; Kuzmina, Nina

    2013-04-01

    Provenance trial of Scots pine in Boguchany forestry of Krasnoyarsk krai is conducted on two different soils - dark-grey loam forest soil and sod-podzol sandy soil. Complex of negative factors for plant growth and development appears in dry conditions of sandy soil. It could results in decrease of resistance to diseases. Sandy soils in different climatic zones have such common traits as low absorbing capacity, poorness of elemental nutrition, low microbiological activity and moisture capacity, very high water permeability. But Scots pine trees growing in such conditions could have certain advantages and perspectives of use. In the scope of climate change (global warming) the study of Scots pine growth on sandy soil become urgent because of more frequent appearance of dry seasons. Purpose of the work is revelation of radial growth features of Scots pine with different origin in dry conditions of sandy soil and assessment of external factors influence. The main feature of radial growth of majority of studied pine provenances in conditions of sandy soil is presence of significant variation of increment with distinct decline in 25-years old with loss of tree rings in a number of cases. The reason of it is complex of factors: deficit of June precipitation and next following outbreak of fungal disease. Found «frost rings» for all trees of studied clymatypes in 1992 are the consequence of temperature decline from May 21 to June 2 - from 23 down to 2 degree Celsius. Perspective climatypes with biggest radial increments and least sensitivity to fungal disease were revealed. Eniseysk and Vikhorevka (from Krasnoyarsk krai and Irkutsk oblast)provenances of pine have the biggest radial increments, the least sensitivity to Cenangium dieback and smallest increments decline. These climatypes are in the group of perspective provenances and in present time they are recommended for wide trial in the region for future use in plantation forest growing. Kandalaksha (Murmansk oblast

  3. The effect of growth conditions on flavonols and anthocyanins accumulation in green and red lettuce

    Directory of Open Access Journals (Sweden)

    Klaudia BRÜCKOVÁ

    2016-12-01

    Full Text Available The aim of the study was to investigate the effect of different growth conditions on anthocyanins and flavonols accumulation in leaves of green and red loose leaf lettuce (Lactuca sativa var. crispa. Lettuce plants were grown in three types of conditions, in greenhouse (I. variant, behind clear glass in field (II. variant and in open field conditions (III. variant. Estimation of anthocyanins and flavonols content was done by non-destructive measurements with optical fluorescence sensor Multiplex® 3 (Force-A, France. It was estimated that green lettuce varieties had a greater flavonols content compared to red lettuce varieties in all experimental variants. The highest level of flavonols was detected in leaves of green variety Zoltán (1.218 RU and in red lettuce had the highest amount of flavonols in variety Carmesi (1.095 RU. At the same time red lettuce varieties were characterized by higher anthocyanins content. Parameter anthocyanin index is correlated with visible red coloration of leaves. The highest content of anthocyanins was detected in variety Oakly (0.867 RU. Under the open field conditions was found statistically significant higher (P < 0.05 flavonols and anthocyanins level in both green and red lettuce leaves compared to greenhouse conditions. It may be connected with intensification of flavonoids biosynthesis and accumulation which normally stimulated by sun irradiation, especially UV-B radiation.

  4. Membrane protein profiling of Acidovorax avenae subsp. avenae under various growth conditions.

    Science.gov (United States)

    Li, Bin; Wang, Li; Ibrahim, Muhammad; Ge, Mengyu; Wang, Yanli; Mannan, Shazia; Asif, Muhammad; Sun, Guochang

    2015-06-01

    Membrane proteins (MPs) of plant pathogenic bacteria have been reported to be able to regulate many essential cellular processes associated with plant disease. The aim of the current study was to examine and compare the expression of MPs of the rice bacterial pathogen Acidovorax avenae subsp. avenae strain RS-1 under Luria-Bertani (LB) medium, M9 medium, in vivo rice plant conditions and leaf extract (LE) medium mimicking in vivo plant condition. Proteomic analysis identified 95, 72, 75, and 87 MPs under LB, in vivo, M9 and LE conditions, respectively. Among them, six proteins were shared under all tested growth conditions designated as abundant class of proteins. Twenty-six and 21 proteins were expressed uniquely under in vivo versus LB medium and LE versus M9 medium, respectively, with 17 proteins common among these uniquely induced proteins. Moreover, most of the shared proteins are mainly related to energy metabolism, transport of small molecules, protein synthesis and secretion as well as virulence such as NADH, OmpA, secretion proteins. Therefore, the result of this study not only suggests that it may be an alternate method to analyze the in vivo expression of proteins by using LE medium to mimic plant conditions, but also reveals that the two sets of differentially expressed MPs, in particular the common MPs between them, might be important in energy metabolism, stress response and virulence of A. avenae subsp. avenae strain RS-1.

  5. Ions, metabolites, and cells: Water as a reporter of surface conditions during bacterial growth

    Science.gov (United States)

    Jarisz, Tasha A.; Lane, Sarah; Gozdzialski, Lea; Hore, Dennis K.

    2018-06-01

    Surface-specific nonlinear vibrational spectroscopy, combined with bulk solution measurements and imaging, is used to study the surface conditions during the growth of E. coli. As a result of the silica high surface charge density, the water structure at the silica-aqueous interface is known to be especially sensitive to pH and ionic strength, and surface concentration profiles develop that can be appreciably different from the bulk solution conditions. We illustrate that, in the presence of growing cells, a unique surface micro-environment is established as a result of metabolites accumulating on the silica surface. Even in the subsequent absence of the cells, this surface layer works to reduce the interfacial ionic strength as revealed by the enhanced signal from surface water molecules. In the presence of growing cells, an additional boost in surface water signal is attributed to a local pH that is higher than that of the bulk solution.

  6. Soil texture and climatc conditions for biocrust growth limitation: a meta analysis

    Science.gov (United States)

    Fischer, Thomas; Subbotina, Mariia

    2015-04-01

    Along with afforestation, attempts have been made to combat desertification by managing soil crusts, and is has been reported that recovery rates of biocrusts are dependent on many factors, including the type, severity, and extent of disturbance; structure of the vascular plant community; conditions of adjoining substrates; availability of inoculation material; and climate during and after disturbance (Belnap & Eldridge 2001). Because biological soil crusts are known to be more stable on and to prefer fine substrates (Belnap 2001), the question arises as to how successful crust management practices can be applied to coarser soil. In previous studies we observed similar crust biomasses on finer soils under arid and on coarser soils under temperate conditions. We hypothesized that the higher water holding capacity of finer substrates would favor crust development, and that the amount of silt and clay in the substrate that is required for enhanced crust development would vary with changes in climatic conditions. In a global meta study, climatic and soil texture threshold values promoting BSC growth were derived. While examining literature sources, it became evident that the amount of studies to be incorporated into this meta analysis was reversely related to the amount of common environmental parameters they share. We selected annual mean precipitaion, mean temperature and the amount of silt and clay as driving variables for crust growth. Response variable was the "relative crust biomass", which was computed per literature source as the ratio between each individual crust biomass value of the given study to the study maximum value reported. We distinguished lichen, green algal, cyanobacterial and moss crusts. To quantify threshold conditions at which crust biomass responded to differences in texture and climate, we (I) determined correlations between bioclimatic variables, (II) calculated linear models to determine the effect of typical climatic variables with soil

  7. The kinetics of dolomite reaction rim growth under isostatic and non-isostatic pressure conditions

    Science.gov (United States)

    Helpa, V.; Rybacki, E.; Morales, L. G.; Abart, R.; Dresen, G. H.

    2013-12-01

    During burial and exhumation, rocks are simultaneously exposed to metamorphic reactions and tectonic stresses. Therefore, the reaction rate of newly formed minerals may depend on chemical and mechanical driving forces. Here, we investigate the reaction kinetics of dolomite (CaMg[CO3]2) rim growth by solid-state reactions experiments on oriented calcite (CaCO3) and magnesite (MgCO3) single crystals under isostatic and non-isostatic pressure conditions. Cylindrical samples of 3-5 mm length and 7 mm diameter were drilled and polished perpendicular to the rhombohedral cleavage planes of natural clear crystals. The tests were performed using a Paterson-type deformation apparatus at P = 400 MPa confining pressure, temperatures, T, between 750 and 850°C, and reaction durations, t, of 2 - 146 h to calculate the kinetic parameters of dolomite rim growth under isostatic stress conditions. For non-isostatic reaction experiments we applied in addition differential stresses, σ, up to 40 MPa perpendicular to the contact interface at T = 750°C for 4 - 171 h duration, initiating minor inelastic deformation of calcite. The thickness of the resulting dolomite reaction rims increases linearly with the square root of time, indicating a diffusion-controlled reaction. The rims consist of two different textural domains. Granular dolomite grains (≈ 2 -5 μm grain size) form next to calcite and elongated palisade-shaped grains (1-6 μm diameter) grow perpendicular to the magnesite interface. Texture measurements with the electron backscatter diffraction technique indicate that the orientations of dolomite grains are mainly influenced by the orientation of the calcite educt crystal, in particular in the granular rim. To some extent, the texture of dolomite palisades is also influenced by the orientation of magnesite. The thickness of the two individual layers increases with temperature. At 400 MPa isostatic pressure, T = 750°C and t = 29 hours, a 5 μm thick granular dolomite layer

  8. Plasticity of Streptomyces coelicolor membrane composition under different growth conditions and during development

    Directory of Open Access Journals (Sweden)

    Mario eSandoval-Calderón

    2015-12-01

    Full Text Available Streptomyces coelicolor is a model actinomycete that is well known for the diversity of its secondary metabolism and its complex life cycle. As a soil inhabitant, it is exposed to heterogeneous and frequently changing environmental circumstances. In the present work, we studied the effect of diverse growth conditions and phosphate depletion on its lipid profile and the relationship between membrane lipid composition and development in S. coelicolor. The lipid profile from cultures grown on solid media, which is closer to the natural habitat of this microorganism, does not resemble the previously reported lipid composition from liquid grown cultures of S. coelicolor. Wide variations were also observed across different media, growth phases, and developmental stages indicating active membrane remodeling. Ornithine lipids (OL are phosphorus-free polar lipids that were accumulated mainly during sporulation stages, but were also major components of the membrane under phosphorus limitation. In contrast, phosphatidylethanolamine, which had been reported as one of the major polar lipids in the genus Streptomyces, is almost absent under these conditions. We identified one of the genes responsible for the synthesis of OL (SCO0921 and found that its inactivation causes the absence of OL, precocious morphological development and actinorhodin production. Our observations indicate a remarkable plasticity of the membrane composition in this bacterial species, reveal a higher metabolic complexity than expected, and suggest a relationship between cytoplasmic membrane components and the differentiation programs in S. coelicolor.

  9. Influence of storage conditions on the release of growth factors in platelet-rich blood derivatives

    Directory of Open Access Journals (Sweden)

    Düregger Katharina

    2016-09-01

    Full Text Available Thrombocytes can be concentrated in blood derivatives and used as autologous transplants e.g. for wound treatment due to the release of growth factors such as platelet derived growth factor (PDGF. Conditions for processing and storage of these platelet-rich blood derivatives influence the release of PDGF from the platelet-bound α-granules into the plasma. In this study Platelet rich plasma (PRP and Platelet concentrate (PC were produced with a fully automated centrifugation system. Storage of PRP and PC for 1 h up to 4 months at temperatures between −20°C and +37°C was applied with the aim of evaluating the influence on the amount of released PDGF. Storage at −20°C resulted in the highest release of PDGF in PRP and a time dependency was determined: prolonged storage up to 1 month in PRP and 10 days in PC increased the release of PDGF. Regardless of the storage conditions, the release of PDGF per platelet was higher in PC than in PRP.

  10. Survival, food consumption and growth of Norway lobster (Nephrops norvegicus) kept in laboratory conditions.

    Science.gov (United States)

    Mente, Elena

    2010-09-01

    Successful commercial aquaculture of crustacean species is dependent on satisfying their nutritional requirements and on producing rapidly growing and healthy animals. The results of the present study provide valuable information for feeding habits and growth of Nephrops norvegicus L., 1758) under laboratory conditions. The aim of the present study was to examine food consumption, growth and physiology of the Norway lobster N. norvegicus under laboratory conditions. N. norvegicus (15 g wet weight) were distributed into 1001 tanks consisting of five numbered compartments each. They were fed the experimental diets (frozen mussels and pellets) for a period of 6 months. A group of starved Nephrops was stocked and fasted for 8 months. Although Nephrops grew well when fed the frozen mussels diet, feeding on a dry pellet feed was unsatisfactory. The starvation group, despite the fact that showed the highest mortality (50%), exhibited a remarkable tolerance to the lack of food supply. The study offers further insight by correlating the amino acid profiles of Nephrops tail muscle with the two diets. The deviations from the mussel's diet for asparagine, alanine and glutamic acid suggest a deficiency of these amino acids in this diet. The results of the present study showed that the concentrations of free amino acids are lower in relative amount than those of protein-bound amino acids, except for arginine, proline and glycine. The present study contributes to the improvement of our knowledge on nutritional requirements of the above species. © 2010 ISZS, Blackwell Publishing and IOZ/CAS.

  11. Influence of hydrogen on crack growth rate of alloy 690 CW in PWR conditions

    International Nuclear Information System (INIS)

    Garcia Redondo, M.S.; Perosanz, F.J.; Lapena, J.; Gomez-Briceno, D.

    2015-01-01

    The influence of hydrogen concentration is well established for Alloy 600 and other nickel base alloys as Alloy 182/ 82 weld metals and X-750. It is accepted that for these materials maximum crack growth rate peaks close to Ni/NiO phase boundary. The influence of the hydrogen on the CGR of Alloy 690 is not well established. Available results for Alloy 690 are scarce and not conclusive. Results obtained by CIEMAT, in conditions representative of the PWR operating plants, indicated an apparent crack growth rate increase by a 3 factor when the hydrogen concentration increased from 35 to 81 cm -3 of H 2 /kg H 2 O. In order to gain some insight into the influence of the hydrogen, a new test has been performed with 20 cm -3 H 2 /kg H 2 O at 360 Celsius degrees, concentration close to Ni/NiO phase boundary. The material used was extruded control rod drive mechanism (CRDM) tubes with homogeneous microstructure. Rolling and tensile straining was applied to the CRDM material to obtain 20% of cold work in order to simulate the strain condition expected in the Heat Affected Zone (HAZ). (authors)

  12. An ultraviolet B condition that affects growth and defense in Arabidopsis.

    Science.gov (United States)

    Vandenbussche, Filip; Yu, Na; Li, Weidong; Vanhaelewyn, Lucas; Hamshou, Mohamad; Van Der Straeten, Dominique; Smagghe, Guy

    2018-03-01

    Ultraviolet B light (UV-B, 280-315 nm) is the shortest wavelength of the solar spectrum reaching the surface of the Earth. It has profound effects on plants, ranging from growth regulation to severe metabolic changes. Low level UV-B mainly causes photomorphogenic effects while higher levels can induce stress, yet these effects tend to overlap. Here we identified a condition that allows growth reduction without obvious detrimental stress in wild type Arabidopsis rosette plants. This condition was used to study the effects of a daily UV-B dose on plant characteristics of UV-B adapted plants in detail. Exploration of the transcriptome of developing leaves indicated downregulation of genes involved in stomata formation by UV-B, while at the same time genes involved in photoprotective pigment biosynthesis were upregulated. These findings correspond with a decreased stomatal density and increased UV-B absorbing pigments. Gene ontology analysis revealed upregulation of defense related genes and meta-analysis showed substantial overlap of the UV-B regulated transcriptome with transcriptomes of salicylate and jasmonate treated as well as herbivore exposed plants. Feeding experiments showed that caterpillars of Spodoptera littoralis are directly affected by UV-B, while performance of the aphid Myzus persicae is diminished by a plant mediated process. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Effects of climatic conditions and soil properties on Cabernet Sauvignon berry growth and anthocyanin profiles.

    Science.gov (United States)

    Cheng, Guo; He, Yan-Nan; Yue, Tai-Xin; Wang, Jun; Zhang, Zhen-Wen

    2014-09-02

    Climatic conditions and soil type have significant influence on grape ripening and wine quality. The reported study was conducted in two "Cabernet Sauvignon (Vitis vinifera L.V)" vineyards located in Xinjiang, a semiarid wine-producing region of China during two vintages (2011 and 2012). The results indicate that soil and climate affected berry growth and anthocyanin profiles. These two localities were within a distance of 5 km from each other and had soils of different physical and chemical composition. For each vineyard, the differences of anthocyanin concentrations, and parameters concerning berry growth and composition between the two years could be explained by different climatic conditions. Soil effect was studied by investigation of differences in berry composition and anthocyanin profiles between the two vineyards in the same year, which could be explained mainly by the different soil properties, vine water and nitrogen status. Specifically, the soils with less water and organic matter produced looser clusters, heavier berry skins and higher TSS, which contributed to the excellent performance of grapes. Compared with 2011, the increases in anthocyanin concentrations for each vineyard in 2012 could be attributed to smaller number of extreme temperature (>35 °C) days and rainfall, lower vine water status and N level. The explanation for higher anthocyanin concentrations in grape skins from the soils with less water and organic matter could be the vine status differences, lighter berry weight and heavier skin weight at harvest. In particular, grapes from the soils with less water and organic matter had higher levels of 3'5'-substituded, O-methylated and acylated anthocyanins, which represented a positive characteristic conferring more stable pigmentation to the corresponding wine in the future. The present work clarifies the effects of climate and soil on berry growth and anthocyanin profiles, thus providing guidance for production of high-quality wine grapes

  14. Homogeneity and heterogeneity in amylase production by Bacillus subtilis under different growth conditions.

    Science.gov (United States)

    Ploss, Tina N; Reilman, Ewoud; Monteferrante, Carmine G; Denham, Emma L; Piersma, Sjouke; Lingner, Anja; Vehmaanperä, Jari; Lorenz, Patrick; van Dijl, Jan Maarten

    2016-03-29

    Bacillus subtilis is an important cell factory for the biotechnological industry due to its ability to secrete commercially relevant proteins in large amounts directly into the growth medium. However, hyper-secretion of proteins, such as α-amylases, leads to induction of the secretion stress-responsive CssR-CssS regulatory system, resulting in up-regulation of the HtrA and HtrB proteases. These proteases degrade misfolded proteins secreted via the Sec pathway, resulting in a loss of product. The aim of this study was to investigate the secretion stress response in B. subtilis 168 cells overproducing the industrially relevant α-amylase AmyM from Geobacillus stearothermophilus, which was expressed from the strong promoter P(amyQ)-M. Here we show that activity of the htrB promoter as induced by overproduction of AmyM was "noisy", which is indicative for heterogeneous activation of the secretion stress pathway. Plasmids were constructed to allow real-time analysis of P(amyQ)-M promoter activity and AmyM production by, respectively, transcriptional and out-of-frame translationally coupled fusions with gfpmut3. Our results show the emergence of distinct sub-populations of high- and low-level AmyM-producing cells, reflecting heterogeneity in the activity of P(amyQ)-M. This most likely explains the heterogeneous secretion stress response. Importantly, more homogenous cell populations with regard to P(amyQ)-M activity were observed for the B. subtilis mutant strain 168degUhy32, and the wild-type strain 168 under optimized growth conditions. Expression heterogeneity of secretory proteins in B. subtilis can be suppressed by degU mutation and optimized growth conditions. Further, the out-of-frame translational fusion of a gene for a secreted target protein and gfp represents a versatile tool for real-time monitoring of protein production and opens novel avenues for Bacillus production strain improvement.

  15. Effects of Climatic Conditions and Soil Properties on Cabernet Sauvignon Berry Growth and Anthocyanin Profiles

    Directory of Open Access Journals (Sweden)

    Guo Cheng

    2014-09-01

    Full Text Available Climatic conditions and soil type have significant influence on grape ripening and wine quality. The reported study was conducted in two “Cabernet Sauvignon (Vitis vinifera L.V” vineyards located in Xinjiang, a semiarid wine-producing region of China during two vintages (2011 and 2012. The results indicate that soil and climate affected berry growth and anthocyanin profiles. These two localities were within a distance of 5 km from each other and had soils of different physical and chemical composition. For each vineyard, the differences of anthocyanin concentrations, and parameters concerning berry growth and composition between the two years could be explained by different climatic conditions. Soil effect was studied by investigation of differences in berry composition and anthocyanin profiles between the two vineyards in the same year, which could be explained mainly by the different soil properties, vine water and nitrogen status. Specifically, the soils with less water and organic matter produced looser clusters, heavier berry skins and higher TSS, which contributed to the excellent performance of grapes. Compared with 2011, the increases in anthocyanin concentrations for each vineyard in 2012 could be attributed to smaller number of extreme temperature (>35 °C days and rainfall, lower vine water status and N level. The explanation for higher anthocyanin concentrations in grape skins from the soils with less water and organic matter could be the vine status differences, lighter berry weight and heavier skin weight at harvest. In particular, grapes from the soils with less water and organic matter had higher levels of 3′5′-substituded, O-methylated and acylated anthocyanins, which represented a positive characteristic conferring more stable pigmentation to the corresponding wine in the future. The present work clarifies the effects of climate and soil on berry growth and anthocyanin profiles, thus providing guidance for production of

  16. Impacts of Plant Growth-Promoting Rhizobacteria-based Biostimulants on Wheat Growth under Greenhouse and Field Conditions

    OpenAIRE

    Nguyen, Minh; Ongena, Marc; Colinet, Gilles; Vandenbol, Micheline; Spaepen, Stijn; Bodson, Bernard; Jijakli, Haissam; du Jardin, Patrick; Delaplace, Pierre

    2015-01-01

    Plant Growth-Promoting Rhizobacteria (PGPR) are one of the main biostimulant classes due to their capacity of stimulating root growth and enhancing soil mineral availability, hence increasing nutrient use efficiency in crops. The aim of this study is to screen commercially PGPR-containing products to enhance wheat growth and yield in combination with an optimized nitrogen (N) fertilizer application scheme. This could lead to a significant reduction of N fertilizer application without affectin...

  17. Growth response of Casuarina equisetifolia Forst. rooted stem cuttings to Frankia in nursery and field conditions.

    Science.gov (United States)

    Karthikeyan, A; Chandrasekaran, K; Geetha, M; Kalaiselvi, R

    2013-11-01

    Casuarina equisetifolia Forst. is a tree crop that provides fuel wood, land reclamation, dune stabilization, and scaffolding for construction, shelter belts, and pulp and paper production. C. equisetifolia fixes atmospheric nitrogen through a symbiotic relationship with Frankia, a soil bacterium of the actinobacteria group. The roots of C. equisetifolia produce root nodules where the bacteria fix atmospheric nitrogen, which is an essential nutrient for all plant metabolic activities. However, rooted stem cuttings of elite clones of C. equisetifolia by vegetative propagation is being planted by the farmers of Pondicherry as costeffective method. As the vegetative propagation method uses inert material (vermiculite) for rooting there is no chance for Frankia association. Therefore after planting of these stocks the farmers are applying 150 kg of di-ammonium phosphate (DAP)/acre/year. To overcome this fertilizer usage, the Frankia-inoculated rooted stem cuttings were propagated under nursery conditions and transplanted in the nutrient-deficient soils of Karaikal, Pondicherry (India), in this study. Under nursery experiments the growth and biomass of C. equisetifolia rooted stem cuttings inoculated with Frankia showed 3 times higher growth and biomass than uninoculated control. These stocks were transplanted and monitored for their growth and survival for 1 year in the nutrient-deficient farm land. The results showed that the rooted stem cuttings of C. equisetifolia significantly improved growth in height (8.8 m), stem girth (9.6 cm) and tissue nitrogen content (3.3 mg g-1) than uninoculated controls. The soil nutrient status was also improved due to inoculation of Frankia.

  18. Nanoparticle growth and surface chemistry changes in cell-conditioned culture medium.

    Science.gov (United States)

    Kendall, Michaela; Hodges, Nikolas J; Whitwell, Harry; Tyrrell, Jess; Cangul, Hakan

    2015-02-05

    When biomolecules attach to engineered nanoparticle (ENP) surfaces, they confer the particles with a new biological identity. Physical format may also radically alter, changing ENP stability and agglomeration state within seconds. In order to measure which biomolecules are associated with early ENP growth, we studied ENPs in conditioned medium from A549 cell culture, using dynamic light scattering (DLS) and linear trap quadrupole electron transfer dissociation mass spectrometry. Two types of 100 nm polystyrene particles (one uncoated and one with an amine functionalized surface) were used to measure the influence of surface type. In identically prepared conditioned medium, agglomeration was visible in all samples after 1 h, but was variable, indicating inter-sample variability in secretion rates and extracellular medium conditions. In samples conditioned for 1 h or more, ENP agglomeration rates varied significantly. Agglomerate size measured by DLS was well correlated with surface sequestered peptide number for uncoated but not for amine coated polystyrene ENPs. Amine-coated ENPs grew much faster and into larger agglomerates associated with fewer sequestered peptides, but including significant sequestered lactose dehydrogenase. We conclude that interference with extracellular peptide balance and oxidoreductase activity via sequestration is worthy of further study, as increased oxidative stress via this new mechanism may be important for cell toxicity. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  19. Effects of simulated Mars conditions on the survival and growth of Escherichia coli and Serratia liquefaciens.

    Science.gov (United States)

    Berry, Bonnie J; Jenkins, David G; Schuerger, Andrew C

    2010-04-01

    Escherichia coli and Serratia liquefaciens, two bacterial spacecraft contaminants known to replicate under low atmospheric pressures of 2.5 kPa, were tested for growth and survival under simulated Mars conditions. Environmental stresses of high salinity, low temperature, and low pressure were screened alone and in combination for effects on bacterial survival and replication, and then cells were tested in Mars analog soils under simulated Mars conditions. Survival and replication of E. coli and S. liquefaciens cells in liquid medium were evaluated for 7 days under low temperatures (5, 10, 20, or 30 degrees C) with increasing concentrations (0, 5, 10, or 20%) of three salts (MgCl(2), MgSO(4), NaCl) reported to be present on the surface of Mars. Moderate to high growth rates were observed for E. coli and S. liquefaciens at 30 or 20 degrees C and in solutions with 0 or 5% salts. In contrast, cell densities of both species generally did not increase above initial inoculum levels under the highest salt concentrations (10 and 20%) and the four temperatures tested, with the exception that moderately higher cell densities were observed for both species at 10% MgSO(4) maintained at 20 or 30 degrees C. Growth rates of E. coli and S. liquefaciens in low salt concentrations were robust under all pressures (2.5, 10, or 101.3 kPa), exhibiting a general increase of up to 2.5 orders of magnitude above the initial inoculum levels of the assays. Vegetative E. coli cells were maintained in a Mars analog soil for 7 days under simulated Mars conditions that included temperatures between 20 and -50 degrees C for a day/night diurnal period, UVC irradiation (200 to 280 nm) at 3.6 W m(-2) for daytime operations (8 h), pressures held at a constant 0.71 kPa, and a gas composition that included the top five gases found in the martian atmosphere. Cell densities of E. coli failed to increase under simulated Mars conditions, and survival was reduced 1 to 2 orders of magnitude by the interactive

  20. Early developed section of the jaw as an index of prenatal growth conditions in adult roe deer Capreolus capreolus

    DEFF Research Database (Denmark)

    Høye, Toke Thomas; Forchhammer, Mads Cedergreen

    2006-01-01

    -maturing bones are poor predictors of resource limitations during early development, as later benign conditions may lead to compensatory growth. We analysed the temporal growth dynamics of different sections of the lower jaw of roe deer Capreolus capreolus and found that the medioanterior section of the lower......Increasing evidence suggests that conditions in early life have important consequences for ultimate body size and fitness. Skeletal parts are often used as retrospective indices of body size and growth constraints because of their resistance to seasonal variation in resource availability. Yet, slow...... post partum and, as such, potentially leaves a fingerprint of prenatal growth conditions that is evident even in adult individuals. This supports earlier findings in ungulates of a shift in skeletal growth spurts after weaning, and suggests that the choice of skeletal index for population and cohort...

  1. The impact of vascular endothelial growth factor and basic fibroblast growth factor on cardiac fibroblasts grown under altered gravity conditions

    DEFF Research Database (Denmark)

    Ulbrich, Claudia; Leder, Annekatrin; Pietsch, Jessica

    2010-01-01

    Myocardium is very sensitive to gravitational changes. During a spaceflight cardiovascular atrophy paired with rhythm problems and orthostatic intolerance can occur. The aim of this study was to investigate the impact of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor...

  2. A numerical study of thermal conditions in the THM growth of HgTe

    Science.gov (United States)

    Martínez-Tomás, M. C.; Muñoz-Sanjosé, V.; Reig, C.

    2002-09-01

    A numerical simulation of the travelling heater method (THM) process in the growth of HgTe is carried out. The whole system (furnace, ampoule and charge) is taken into account in the frame of a quasi-steady-state model. The mass conservation condition for the solute in the liquid zone permits the determination of the rate of advance of the crystallisation isotherm as a function of the heater position. We claim to study the evolution of different magnitudes along the growth process, searching for the physical reasons which could be at the origin of defects in the form of thin layers observed in some growing experiences. To solve the governing equations of fluid flow, heat transfer and mass transport we have made use of a commercial code which can run in a PC. The simulation is made by using a three-level strategy, which allows the reduction of the computational effort. In the first level, heat transport is assumed to be by conduction, convection and radiation between the furnace and the ampoule, and by conduction through the ampoule wall, coating, solid and liquid zones. The temperature calculated at this level in the air/ampoule boundary is used as boundary condition for the second and third level. In these two levels the ampoule and its content are studied in detail. Convection in the liquid zone is considered at the second level and thermosolutal convection is finally included at the third level. The analysis of the incoming/outcoming heat flux per second through the ampoule for the whole system shows that the lower part of the ampoule exhibits some ineffectiveness for the heat evacuation at certain positions of the growth run, depending on thermal properties of the whole system and the particular material to be grown. As a consequence, the growth rate suffers a significant variation just for these positions of the heater. From these considerations a plausible interpretation has been proposed to understand the apparition of solvent inclusions in the form of thin

  3. Vector population growth and condition-dependent movement drive the spread of plant pathogens.

    Science.gov (United States)

    Shaw, Allison K; Peace, Angela; Power, Alison G; Bosque-Pérez, Nilsa A

    2017-08-01

    Plant viruses, often spread by arthropod vectors, impact natural and agricultural ecosystems worldwide. Intuitively, the movement behavior and life history of vectors influence pathogen spread, but the relative contribution of each factor has not been examined. Recent research has highlighted the influence of host infection status on vector behavior and life history. Here, we developed a model to explore how vector traits influence the spread of vector-borne plant viruses. We allowed vector life history (growth rate, carrying capacity) and movement behavior (departure and settlement rates) parameters to be conditional on whether the plant host is infected or healthy and whether the vector is viruliferous (carrying the virus) or not. We ran simulations under a wide range of parameter combinations and quantified the fraction of hosts infected over time. We also ran case studies of the model for Barley yellow dwarf virus, a persistently transmitted virus, and for Potato virus Y, a non-persistently transmitted virus. We quantified the relative importance of each parameter on pathogen spread using Latin hypercube sampling with the statistical partial rank correlation coefficient technique. We found two general types of mechanisms in our model that increased the rate of pathogen spread. First, increasing factors such as vector intrinsic growth rate, carrying capacity, and departure rate from hosts (independent of whether these factors were condition-dependent) led to more vectors moving between hosts, which increased pathogen spread. Second, changing condition-dependent factors such as a vector's preference for settling on a host with a different infection status than itself, and vector tendency to leave a host of the same infection status, led to increased contact between hosts and vectors with different infection statuses, which also increased pathogen spread. Overall, our findings suggest that vector population growth rates had the greatest influence on rates of virus

  4. Salmonella Modulates Metabolism During Growth under Conditions that Induce Expression of Virulence Genes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young-Mo; Schmidt, Brian; Kidwai, Afshan S.; Jones, Marcus B.; Deatherage, Brooke L.; Brewer, Heather M.; Mitchell, Hugh D.; Palsson, Bernhard O.; McDermott, Jason E.; Heffron, Fred; Smith, Richard D.; Peterson, Scott N.; Ansong, Charles; Hyduke, Daniel R.; Metz, Thomas O.; Adkins, Joshua N.

    2013-04-05

    Salmonella enterica serovar Typhimurium (S. Typhimurium) is a facultative pathogen that uses complex mechanisms to invade and proliferate within mammalian host cells. To investigate possible contributions of metabolic processes in S. Typhimurium grown under conditions known to induce expression of virulence genes, we used a metabolomics-driven systems biology approach coupled with genome scale modeling. First, we identified distinct metabolite profiles associated with bacteria grown in either rich or virulence-inducing media and report the most comprehensive coverage of the S. Typhimurium metabolome to date. Second, we applied an omics-informed genome scale modeling analysis of the functional consequences of adaptive alterations in S. Typhimurium metabolism during growth under our conditions. Excitingly, we observed possible sequestration of metabolites recently suggested to have immune modulating roles. Modeling efforts highlighted a decreased cellular capability to both produce and utilize intracellular amino acids during stationary phase culture in virulence conditions, despite significant abundance increases for these molecules as observed by our metabolomics measurements. Model-guided analysis suggested that alterations in metabolism prioritized other activities necessary for pathogenesis instead, such as lipopolysaccharide biosynthesis.

  5. Identification and growth conditions of purple non-sulfur photosynthetic bacteria isolated from palm oil mill effluent

    International Nuclear Information System (INIS)

    Radziah Ariffin

    2004-01-01

    An indigenous strain of the purple non-sulphur photosynthetic bacterium, isolated from palm oil mill effluent was presumably identified as species of Rhodopseudomonas palustris. Cultivation in synthetic medium under different conditions indicated that it gave maximum carotenoid and bacteriophyll synthesis under anaerobic conditions in the light with values of 12.6 and 108.1 mg/g dry cell weight respectively. These values were significantly higher than the pigment content obtained from aerobic cultivation. The specific growth rates in anaerobic was twice those in aerobic conditions in the light. Growth was not occurred in anaerobic or aerobic conditions in the dark. (Author)

  6. Photosynthate consumption and carbon turnover in the rhizosphere depending on plant species and growth conditions

    International Nuclear Information System (INIS)

    Sauerbeck, D.R.; Helal, H.M.; Nonnen, S.; Allard, J.-l.

    1982-01-01

    The root tissue which can be isolated from soils represents only part of the total plant carbon incorporation. Between 20 and 40% of the photosynthetic production of plants is expended for root growth and root metabolism. This indicates a striking turnover of energy in the rhizosphere, because relatively litle root-derived organic matter remains there until harvest time. Plant species and variety, soil conditions and temperature were shown to be the most decisive factors governing the assimilate consumption of plant root systems. A special technique is described which enables to study how this extensive turnover affects the surrounding soil depending on its proximity to the roots. Plant-derived carbon can be detected up to 20mm away from the roots. A priming effect has been found on the decomposition of soil organic matter. This explains why, in spite of the rhizo-deposition mentioned, no net-accumulation of carbon in the rhizosphere has been found. (Author) [pt

  7. Comprehensive Study Of Duckweed Cultivation And Growth Conditions Under Controlled Eutrophication

    Directory of Open Access Journals (Sweden)

    Bartošová Alica

    2015-06-01

    Full Text Available The paper discussed the issue of eutrophication. The most conspicuous effect of eutrophication is the creation of dense blooms of noxious, foul-smelling phytoplankton that reduce water clarity and harm water quality. Nutrient concentration, temperature and pH of the water largely influence the growth rate and composition of duckweed in general, but it can be said that the temperature and solar irradiation are the most important factors. In order to compare the rate of biomass increase of duckweed biomass in natural conditions and in a laboratory grown sample was analysed by spectrophotometric methods in UV/VIS region (Spectrophotometer GENESYSTM for the selected nutrients such as ammonium, ammonium nitrogen, nitrite, nitrate, and phosphate.

  8. Device for investigating subcritical crack growth of RPV steel specimens under BWR conditions

    International Nuclear Information System (INIS)

    Anders, D.; Ahlf, J.

    1983-01-01

    An experiment is being prepared to investigate the subcritical crack growth of RPV steel specimens under cyclic load and under the environmental conditions of a BWR with regard to primary water and irradiation. The experiment will be carried out in the VAK reactor Kahl which is a boiling water reactor operating at 71 bar, 286 0 C and generating 16 MW/sub e/. The experimental setup is composed of an open frame to which a string consisting of five compact tension speciments (40 mm thickness) and connecting links is fixed. The specimen chain is set under cyclic load by a pneumatically actuated bellows unit which is attached to the frame top. Specimen strain and crack opening are measured by linear differential transformers; for temperature distribution measurements in the specimens thermocouples are applied

  9. Solvability conditions for dendritic growth in the boundary-layer model with capillary anisotropy

    Science.gov (United States)

    Langer, J. S.; Hong, D. C.

    1986-01-01

    This paper is concerned primarily with the development of an analytic approach to the theory of steady-state velocity selection in the boundary-layer model of dendritic solidification. The two-dimensional version of this model with a fourfold crystalline anisotropy alpha in the surface tension is considered. By extending a WKB method introduced in an earlier paper, the alpha dependence of the selected growth rate is determined in the limit of small alpha; and this rate is studied for large alphas in the limit in which the dimensionless undercooling approaches unity. Portions of the paper are devoted to a reinterpretation of the mathematical structure of the solvability condition in problems of this kind.

  10. Growth of carbon fibres, sheets and tubes on diamond films under high power plasma etching conditions

    Energy Technology Data Exchange (ETDEWEB)

    Villalpando, I. [Centro de Investigacion de los Recursos Naturales, Antigua Normal Rural, Salaices, Lopez, Chihuahua (Mexico); John, P.; Wilson, J. I. B., E-mail: isaelav@hotmail.com [School of Engineering and Physical Sciences, Heriot-Watt University, Riccarton, Edinburgh, EH14-4AS (United Kingdom)

    2017-11-01

    The application of diamond as a plasma facing material for fusion reactors can be limited by unknown reactions between diamond and the chamber materials transported by the plasma. Transformation of diamond to other structures can cause problems such as contamination of the plasma with loose particles or retention of gases. We have seen that diamond thin films are eroded under hydrogen plasma etching, but if silicon is present the growth of various carbon structures on diamond films is observed. We have produced carbon with different morphologies on diamond films including fibres, sheets with flower-like shapes and tubes and proposed growth mechanisms based on the results of scanning electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. Sample surfaces contain silicon and are oxidised having COO and CO groups as seen by XP S analysis. Raman analyses revealed a spectrum typical for graphite combined with that from diamond that remains on the surface after hydrogen bombardment. The results of this sturdy show the experimental conditions in which carbon fibres, sheets and tubes are produced under high-power hydrogen etching of diamond films and open the possibility to other applications such as catalysts, sensors and the production of electrodes. (Author)

  11. Growth and yield of different brassica genotypes under saline sodic conditions

    International Nuclear Information System (INIS)

    Ali, A.; Mahmood, I.A.; Salim, M.

    2013-01-01

    A field study was conducted at farmer's salt-affected field (ECe=12.3 dS m/sup -1/; pH=9.7; SAR=46.2) in Hafizabad to test growth and yield response of six Brassica cultivars (BARD-I, Dunkled, Rainbow, BRS-II, Sultan Raya and cv. 95102-5) under saline sodic conditions. Data on growth and yield parameters were collected randomly (average of five plants per replication) at the time of crop maturity. Ionic concentration in plant tissues and oil content in seeds were also determined. Comparatively more number of branches and pods per plant were produced by cultivar Dunkled closely followed by BARD-I while maximum seed yield (241.7 and 235.1 kg ha ) was obtained from Dunkled and Sultan Raya, respectively which was statistically at par. However, BRS-II and Rainbow showed significantly more percent oil contents in their seeds but genotype Dunkled showed minimum Na+ and K+ concentration in their tissues. (author)

  12. Growth of carbon fibres, sheets and tubes on diamond films under high power plasma etching conditions

    International Nuclear Information System (INIS)

    Villalpando, I.; John, P.; Wilson, J. I. B.

    2017-01-01

    The application of diamond as a plasma facing material for fusion reactors can be limited by unknown reactions between diamond and the chamber materials transported by the plasma. Transformation of diamond to other structures can cause problems such as contamination of the plasma with loose particles or retention of gases. We have seen that diamond thin films are eroded under hydrogen plasma etching, but if silicon is present the growth of various carbon structures on diamond films is observed. We have produced carbon with different morphologies on diamond films including fibres, sheets with flower-like shapes and tubes and proposed growth mechanisms based on the results of scanning electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. Sample surfaces contain silicon and are oxidised having COO and CO groups as seen by XP S analysis. Raman analyses revealed a spectrum typical for graphite combined with that from diamond that remains on the surface after hydrogen bombardment. The results of this sturdy show the experimental conditions in which carbon fibres, sheets and tubes are produced under high-power hydrogen etching of diamond films and open the possibility to other applications such as catalysts, sensors and the production of electrodes. (Author)

  13. Seedling growth in greenhouse conditions of the forest species Dialium guianense (Aubl. Sandwith

    Directory of Open Access Journals (Sweden)

    Georgina Vargas Simon

    2018-01-01

    Full Text Available Dialium guianense is used for its wood and fruit production, and is a tropical tree species native to evergreen forests. Given the threat these forests face, the purpose of this work was to evaluate the initial growth of the plant under greenhouse conditions, for aiming in the development of propagation programs. Seedlings of the species were transplanted to nursery bags under a completely randomized design and grown for 10 months with an initial population of 200 plants. At the end of the experiment, the shoot and root reached lengths of 32.8 and 28.9 cm, respectively. The average number of composite leaves was 12.3 each with seven leaflets. The average biomass was 2.5 g for the shoot, 1.6 g for roots, and 3.7 g for leaves, with a shoot/root around four. The average relative growth rate (RGR was 15 mg g-1 day-. These characteristics indicate that D. guianense is a late successional species.

  14. Fern Stomatal Responses to ABA and CO2 Depend on Species and Growth Conditions.

    Science.gov (United States)

    Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

    2017-06-01

    Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

  15. Deciphering flux adjustments of engineered E. coli cells during fermentation with changing growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    He, Lian [Washington Univ., St. Louis, MO (United States); Xiu, Yu [Rensselaer Polytechnic Inst., Troy, NY (United States); Beijing Univ. of Chemical Technology (China); Jones, J. Andrew [Rensselaer Polytechnic Inst., Troy, NY (United States); Hamilton College, Clinton, NY (United States); Baidoo, Edward E. K. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Keasling, Jay D. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Technical Univ. of Denmark, Lyngby (Denmark); Tang, Yinjie J. [Washington Univ., St. Louis, MO (United States); Koffas, Mattheos A. G. [Rensselaer Polytechnic Inst., Troy, NY (United States)

    2016-12-23

    Microbial fermentation conditions are dynamic, due to transcriptional induction, nutrient consumption, or changes to incubation conditions. In this paper, 13C-metabolic flux analysis was used to characterize two violacein-producing E. coli strains with vastly different productivities, and to profile their metabolic adjustments resulting from external perturbations during fermentation. The two strains were first grown at 37 °C in stage 1, and then the temperature was transitioned to 20 °C in stage 2 for the optimal expression of the violacein synthesis pathway. After induction, violacein production was minimal in stage 3, but accelerated in stage 4 (early production phase) and 5 (late production phase) in the high producing strain, reaching a final concentration of 1.5 mmol/L. On the contrary, ~0.02 mmol/L of violacein was obtained from the low producing strain. To have a snapshot of the temporal metabolic changes in each stage, we performed 13C-MFA via isotopomer analysis of fast-turnover free metabolites. The results indicate strikingly stable flux ratios in the central metabolism throughout the early growth stages. In the late stages, however, the high producer rewired its flux distribution significantly, which featured an upregulated pentose phosphate pathway and TCA cycle, reflux from acetate utilization, negligible anabolic fluxes, and elevated maintenance loss, to compensate for nutrient depletion and drainage of some building blocks due to violacein overproduction. The low producer with stronger promoters shifted its relative fluxes in stage 5 by enhancing the flux through the TCA cycle and acetate overflow, while exhibiting a reduced biomass growth and a minimal flux towards violacein synthesis. Finally, interestingly, the addition of the violacein precursor (tryptophan) in the medium inhibited high producer but enhanced low producer's productivity, leading to hypotheses of unknown pathway regulations (such as metabolite

  16. Effects of sawdust thickness on the growth performance, environmental condition, and welfare quality of yellow broilers.

    Science.gov (United States)

    Shao, Dan; He, Jiao; Lu, Jian; Wang, Qiang; Chang, Lingling; Shi, Shou Rong; Bing, Tong Hai

    2015-01-01

    An experiment was conducted to evaluate the effect of litter thickness on growth performance, immune status, environmental condition, and welfare quality in yellow broilers. In total, 1,800 one-day-old Suqin yellow broilers were raised for 21 d. On d 22, 1,600 birds of similar BW (404±12 g) were randomly selected and placed into 20 indoor pens (8 birds/m2, 10 m2/pen). These birds were assigned to a litter treatment of 4, 8, 12, and 16 cm. Each treatment was repeated in five pens. The results showed that a thicker litter was related to increased BW, daily weight gain, and daily feed intake (Plitter thickness (P=0.320, P=0.353, respectively). Absolute and relative liver weights showed a significant linear response to increasing litter thickness (P=0.01, P=0.001, respectively). The litter moisture content, air ammonia, and CO2 content decreased, whereas the air dust content increased with increasing litter thickness (PLitter thickness had no effect on gait, plumage damage, hock burn or breast skin crusting (P = 0.076, P=0.964, P=0.131, P=0.401, respectively). Plumage cleanliness, foot pad dermatitis, hock swelling and breast blister varied significantly with litter thickness (P=0.027, P=0.011, P=0.014, P=0.042, respectively). The results of this study suggest that an increasing litter thickness has a beneficial effect on the growth performance, environmental condition and welfare of birds. © 2015 Poultry Science Association Inc.

  17. Modified stress intensity factor as a crack growth parameter applicable under large scale yielding conditions

    International Nuclear Information System (INIS)

    Yasuoka, Tetsuo; Mizutani, Yoshihiro; Todoroki, Akira

    2014-01-01

    High-temperature water stress corrosion cracking has high tensile stress sensitivity, and its growth rate has been evaluated using the stress intensity factor, which is a linear fracture mechanics parameter. Stress corrosion cracking mainly occurs and propagates around welded metals or heat-affected zones. These regions have complex residual stress distributions and yield strength distributions because of input heat effects. The authors previously reported that the stress intensity factor becomes inapplicable when steep residual stress distributions or yield strength distributions occur along the crack propagation path, because small-scale yielding conditions deviate around those distributions. Here, when the stress intensity factor is modified by considering these distributions, the modified stress intensity factor may be used for crack growth evaluation for large-scale yielding. The authors previously proposed a modified stress intensity factor incorporating the stress distribution or yield strength distribution in front of the crack using the rate of change of stress intensity factor and yield strength. However, the applicable range of modified stress intensity factor for large-scale yielding was not clarified. In this study, the range was analytically investigated by comparison with the J-integral solution. A three-point bending specimen with parallel surface crack was adopted as the analytical model and the stress intensity factor, modified stress intensity factor and equivalent stress intensity factor derived from the J-integral were calculated and compared under large-scale yielding conditions. The modified stress intensity was closer to the equivalent stress intensity factor when compared with the stress intensity factor. If deviation from the J-integral solution is acceptable up to 2%, the modified stress intensity factor is applicable up to 30% of the J-integral limit, while the stress intensity factor is applicable up to 10%. These results showed that

  18. Initial Conditions Corresponding to Optimal Ion Acceleration in the VINCY Cyclotron

    International Nuclear Information System (INIS)

    Ilic, A. Z.; Ristic-Djurovic, J. L.; Cirkovic, S. T.

    2007-01-01

    The quality of a beam in a cyclotron depends a lot on the choice of initial conditions for acceleration. The criteria defining optimal acceleration as well as the choice of the corresponding initial conditions have been outlined. The results of beam dynamics simulations with optimal and non-optimal initial conditions are compared. (author)

  19. Regeneration efficiency based on genotype, culture condition and growth regulators of eggplant (Solanum melongena L.

    Directory of Open Access Journals (Sweden)

    Md Abdul Muktadir

    2016-01-01

    Full Text Available Several experiments were carried out to establish an efficient regenerating protocol for cultivated eggplant varieties. Among the five varieties cultured on Murashige and Skoog (MS medium with free plant growth regulator (PGR, Nayantara performed better considering the number of shoots/explant (2.48. Considering explant types and culture conditions, better performance was observed (3.68 shoots/explant when seed germination in the dark was proceeded by bottom hypocotyl segments cultured under dark conditions. A higher rate of shoot regeneration was observed in Nayantara when cultured in Zeatin Riboside (ZR and Thidizuron (TDZ supplemented MS medium. The highest number of shoots per explant was produced on MS medium supplemented with 2.0 mg/L ZR and 0.1 mg/L indole acetic acid (6.65 shoots/explant. Proliferation and elongation of the regenerated shoots were obtained in the MS medium with free PGR. The best rooting performance was observed in MS medium supplemented with 2.0 mg/L indole butyric acid. Plantlets with well developed roots and shoots were successfully transferred to soil.

  20. Unearthing Bacillus endophytes from desert plants that enhance growth of Arabidopsis thaliana under abiotic stress conditions

    KAUST Repository

    Bokhari, Ameerah M

    2018-04-01

    Here, we embarked a bioprospecting project that focuses on the isolation and characterization of plant root endophytes, collected from the Thar Desert. A total of 381 endophytes were isolated and based on their 16S rRNA gene sequences, genus Bacillus (58 strains) was identified as the major taxon and only endophytes from this genus were isolated from all plant types. Of the 58 Bacillus strains, only 16 strains were selected for screening of plant growth promotion traits such as P and Zn solubilization, indole-3-acetic acid and siderophore production, and antimicrobial activity. Based on the presence of specific plant growth promotion traits 10 strains were shortlisted for further in vitro screening with A. thaliana; to confirm that these bacteria can confer resilience to plants under salt stress conditions. B. circulans (PK3-15 and PK3-109), B. cereus (PK6-15) B. subtilis (PK3-9) and B. licheniformis (PK5-26) displayed the ability to increased the fresh weight of A. thaliana under salt stress conditions by more than 50 % compared to the uninoculated control. An interesting observation was that B. circulans (PK3-109) (shown to produce IAA exopolysaccharide) and B. circulans (PK3-138) (shown to produce IAA) in vitro results were substantially different as B. circulans (PK3-138) decreased the total fresh weight of A. thaliana by 47 %, whilst B. circulans (PK3-109) was one of the best performing strains. Thus, the genomes of these two strains were sequences to unravel the molecular versatility of B. circulans strains, specifically with respect to their interaction with plants. Most of the genome of these strains is identical but the most interesting feature was the presence of 1/ the DegS–DegU two-component system that is known to mediate the salt stress response and DegU also represses toxin wapA similar to antitoxin wapI, and 2/ YxiG, a gene in the unique orthogroup of PK3-109 was found to be linked to WapI. Thus, PK3-138 substantially decreasing the total fresh

  1. Increased water-use efficiency does not lead to enhanced tree growth under xeric and mesic conditions

    NARCIS (Netherlands)

    Lévesque, M.; Siegwolf, R.; Saurer, M.; Eilmann, B.; Rigling, A.

    2014-01-01

    Higher atmospheric CO2 concentrations (ca ) can under certain conditions increase tree growth by enhancing photosynthesis, resulting in an increase of intrinsic water-use efficiency (i WUE) in trees. However, the magnitude of these effects and their interactions with changing climatic conditions are

  2. Are oysters being bored to death? Influence of Cliona celata on Crassostrea virginica condition, growth and survival.

    Science.gov (United States)

    Carroll, John M; O'Shaughnessy, Kathryn A; Diedrich, Grant A; Finelli, Christopher M

    2015-11-17

    The boring sponge Cliona celata is a nuisance species that can have deleterious effects on eastern oyster Crassostrea virginica growth, condition, and survival. Surprisingly, however, these effects have not been well documented and when examined, results have been equi-vocal. In this study, we provide a direct comparison of growth, condition, and survival of sponge-colonized and uncolonized oysters in southeast North Carolina in 2 separate experiments. In the first experiment, sponge-colonized oysters exhibited significantly slower growth rates, reduced condition, and lower survival relative to uncolonized oysters, although results may have been confounded by oyster source. In the second experiment, using smaller oysters from the same source population, growth rate was again significantly reduced in colonized oysters relative to uncolonized oysters, however neither condition nor survival differed. In field surveys of the same population, colonized individuals across a range of sizes demonstrated significantly reduced condition. Further, condition index was negatively correlated with sponge biomass, which was positively correlated with oyster size, suggesting that the impact of the sponge changes with ontogeny. By investigating clearance rates, tissue isotopic and nutrient content, as well as caloric value, this study provides further evidence that sponge presence causes the oysters to divert energy into costly shell maintenance and repair at the expense of shell and somatic growth. Thus, although variable, our results demonstrate negative impacts of sponge infestation on oyster demographics, particularly as oysters grow larger.

  3. Accumulation of fatty acids in Chlorella vulgaris under heterotrophic conditions in relation to activity of acetyl-CoAcarboxylase, temperature, and co-immobilization with Azospirillum brasilense [corrected].

    Science.gov (United States)

    Leyva, Luis A; Bashan, Yoav; Mendoza, Alberto; de-Bashan, Luz E

    2014-10-01

    The relation between fatty acid accumulation, activity of acetyl-CoA carboxylase (ACC), and consequently lipid accumulation was studied in the microalgae Chlorella vulgaris co-immobilized with the plant growth-promoting bacterium Azospirillum brasilense under dark heterotrophic conditions with Na acetate as a carbon source. In C. vulgaris immobilized alone, cultivation experiments for 6 days showed that ACC activity is directly related to fatty acid accumulation, especially in the last 3 days. In co-immobilization experiments, A. brasilense exerted a significant positive effect over ACC activity, increased the quantity in all nine main fatty acids, increased total lipid accumulation in C. vulgaris, and mitigated negative effects of nonoptimal temperature for growth. No correlation between ACC activity and lipid accumulation in the cells was established for three different temperatures. This study demonstrated that the interaction between A. brasilense and C. vulgaris has a significant effect on fatty acid and lipid accumulation in the microalgae.

  4. Accumulation fatty acids of in Chlorella vulgaris under heterotrophic conditions in relation to activity of acetyl-CoA carboxylase, temperature, and co-immobilization with Azospirillum brasilense

    Science.gov (United States)

    Leyva, Luis A.; Bashan, Yoav; Mendoza, Alberto; de-Bashan, Luz E.

    2014-10-01

    The relation between fatty acid accumulation, activity of acetyl-CoA carboxylase (ACC), and consequently lipid accumulation was studied in the microalgae Chlorella vulgaris co-immobilized with the plant growth-promoting bacterium Azospirillum brasilense under dark heterotrophic conditions with Na acetate as a carbon source. In C. vulgaris immobilized alone, cultivation experiments for 6 days showed that ACC activity is directly related to fatty acid accumulation, especially in the last 3 days. In co-immobilization experiments, A. brasilense exerted a significant positive effect over ACC activity, increased the quantity in all nine main fatty acids, increased total lipid accumulation in C. vulgaris, and mitigated negative effects of nonoptimal temperature for growth. No correlation between ACC activity and lipid accumulation in the cells was established for three different temperatures. This study demonstrated that the interaction between A. brasilense and C. vulgaris has a significant effect on fatty acid and lipid accumulation in the microalgae.

  5. Growth Responses of Acacia mangium and Paraserianthes falcataria Seedlings on Different Soil Origin under Nursery Condition

    Directory of Open Access Journals (Sweden)

    Tirtha Ayu Paramitha

    2015-12-01

    Full Text Available The objective of the present study was to examine the growth responses of Acacia mangium (mangium and Paraserianthes falcataria (sengon seedlings growing on different soil origin under nursery condition. This study was started in September 2012 and terminated in March 2013.  The seedlings were grown from seeds sown in a plastic box filled with sterilized sands. One week after sowing, the seedlings were transplanted into polybags contained sterilized soils originated from secondary forest, Imperata cylindrica grassland and ex-coal mining. The number of all seedlings were 180 seedlings consisted of 3 different soils, 2 species of seedlings with 10 seedlings replicated 3 times. Assessment was conducted one week after transplanting, then subsequently monitored every 2 weeks, except dry weighing and counting nodules were performed at the end of the study. A completely randomized design was used in this study. The data was analyzed using Costat software. The study resulted that the different of soil origin influenced on all growth variables of mangium and sengon of 4.5 months old. The survival rate of seedlings, height and diameter increments, dry weight and root nodules were better in both species of seedlings growing on soil originated from secondary forest and Imperata grassland compared with the soil from ex-coal mining. But the survival rates of sengon seedlings were higher than that of mangium on these three soils. The highest dry weight of sengon seedlings was achieved on soil originated from secondary forest. In the present study, soil originated from secondary forest increased more in weight of shoot than root, so that the shoot-root ratio was unbalanced more than one. Based on the results of this study, it is recommended that soil from secondary forest and Imperata grassland can be used as growing media for mangium and sengon seedlings in the nursery.

  6. Short Communication Synergistic effect of rhizobia and plant growth promoting rhizobacteria on the growth and nodulation of lentil seedlings under axenic conditions

    Directory of Open Access Journals (Sweden)

    Muhammad Zafar-ul-Hye

    2013-05-01

    Full Text Available Plant growth promoting rhizobacteria (PGPR containing ACC-deaminase in combination with rhizobia can improve the growth and nodulation in plants by suppressing the endogenous level of ethylene. In the present study, ten strains, each of PGPR and rhizobia from the previously screened cultures were tested for their effect as co-inoculants on growth and nodulation of lentil in growth pouches under axenic conditions. Results showed that most of the combinations improved the lentil growth as compared to the un-inoculated control. Maximum increase in shoot length (1.87 fold, root length (1.97 fold and total biomass (1.98 fold over the un-inoculated control was observed in the treatment where the lentil seedlings were inoculated with the combination Z24P10. Co-inoculation also improved the nodulation in lentil and the maximum number of nodules plant-1 (24 nodules were observed in the combination Z22P10. However, there was no nodulation in few combinations. It is concluded that the co-inoculation with rhizobia and PGPR containing ACC-deaminase has improved the growth and nodulation in lentil under axenic conditions and the selected combinations may be evaluated in pot and field trials

  7. The influence of stress conditions on the growth of selected lactic acid bacteria

    International Nuclear Information System (INIS)

    Bok, H.E.

    1985-01-01

    A study was undertaken to determine the effects of certain stress conditions on selected lactic acid bacteria. Where recontamination occurred, lactic acid bacteria was already the dominant bacterial group, with counts of higher than 10 6 /g in vacuum-packaged 'shelf stable' meat products after 1 week storage at 25 and 37 degrees Celsius respectively. Some of the isolates were capable of growing at a pH of 3,9. The minimum pH for growth of a specific culture was dependant on the type of acid that was used to lower the pH. Lactic and acetic acid had the highest inhibitory action. Hydrochloric and citric acid showed similar inhibitory effects, while the effects when using ascorbic acid or gluconic acid for lowering the pH were also fairly similar. Increase in the activity of certain lactic acid bacteria was noticed where the ratio of undissociated to dissociated citric acid in the medium was increased. After exceeding a concentration of 0,048 moles/l undissosiated citric acid in the medium, the activity of the majority of cultures was progressively inhibited. This phenomenon was also found with acetic acid for certain cultures. Selected lactic acid bacteria were resistant to an water activity (a (sub w)) of 0,94 in MRS broth, where NaCl or glycerol was used as a humectant. The minimum a (sub w) for growth was dependent on the type of humectant used. Concentrations of sodium benzoate and potassium sorbate were necessary to inhibit the majority of strains. The % inhibition by sodium benzoate and methyl paraben did not significantly change with a lowering in the pH of the growth medium. Except in the case of lactic acid, the different acids used to lower the pH of the medium did not have a significant effect on the % inhibition by the chemical preservatives. For the cocci, gamma D 10 values of between 0,82 and 1,29 kGy were recorded, whereas the lactobacilli were less resistant to gamma rays, with D 10 values of between 0,21 and 0,54 kGy

  8. Fatigue behaviour and crack growth of ferritic steel under environmental conditions

    International Nuclear Information System (INIS)

    Herter, K.H.; Schuler, X.; Weissenberg, T.

    2012-01-01

    The assessment of fatigue and cyclic crack growth behaviour of safety relevant components is of importance for the ageing management with regard to safety and reliability. For cyclic stress evaluation different codes and standards provide fatigue analysis procedures to be performed considering the various mechanical and thermal loading histories and geometric complexities of the components. For the fatigue design curves used as a limiting criteria the influence of different factors like e.g. environment, surface finish and temperature must be taken into consideration in an appropriate way. Fatigue tests were performed in the low cycle fatigue (LCF) und high cycle fatigue (HCF) regime with low alloy steels as well as with Nb- and Ti-stabilized German austenitic stainless steels in air and high temperature (HT) boiling water reactor environment to extend the state of knowledge of environmentally assisted fatigue (EAF) as it can occur in boiling water reactor (BWR) plants. Using the reactor pressure vessel (RPV) steel 22NiMoCr3-7 experimental data were developed to verify the influence of BWR coolant environment (high purity water as well as sulphate containing water with 90 ppb SO 4 at a test temperature of 240 C and an oxygen content of 400 ppb) on the fatigue life and to extend the basis for a reliable estimation of the remaining service life of reactor components. Corresponding experiments in air were performed to establish reference data to determine the environmental correction factor F en accounting for the environment. The experimental results are compared with international available mean data curves, the new design curves and on the basis of the environmental factor F en . Furthermore the behaviour of steel 22NiMoCr3-7 in oxygenated high temperature water under transient loading conditions was investigated with respect to crack initiation and cyclic crack growth. In this process the stress state of the specimen and the chemical composition of the high

  9. ADAPTATION TO UNFAVORABLE CONDITIONS OF GROWTH: PATHOGENICITY OF ACHOLEPLASMA LAIDLAWII PG8

    Directory of Open Access Journals (Sweden)

    Maxim V. Trushin

    2006-11-01

    Full Text Available ABSTRACT:As a result of cultivation of A. laidlawii PG8 cells on the deficient medium during 480 days, the mycoplasma culture adapted in vitro to unfavorable growth conditions was obtained. The culture consisted of cells with sizes less than 0.2 µm and features of A. laidlawii PG8 ultramicroforms, nanocells. A. laidlawii PG8 culture adapted in vitro to unfavorable growth conditions shows more evident phytopathogenicity than the unadapted one. Infecting plants V. minor L. by A. laidlawii PG8 culture adapted in vitro to UGC resulted in the appearance of chloroses in 75%, necrosis – 50%, leaves marcescence – 50% and abnormalities of bine development in 30% of plants through 12 days, while infecting plants by A. laidlawii PG8 culture unadapted to UGC led to respective signs in 40%, 25%, 25% and 0% of samples, respectively, through 30 days. The ability of A. laidlawii PG8 to form UMF resistant to stress factors in UGC with high phytopathogenic potential seems to demand a new approach to investigate the precise mechanisms of interacting the mycoplasma with host organisms.RESUMENComo resultado del cultivo de células de A. laidlawii PG8 en medio deficiente durante 480 días, fue obtenido un cultivo de mycoplasma adaptado in vitro a las condiciones desfavorables del crecimiento. El cultivo consistió en células con tamaño menor de 0.2 µm y características PG8 ultramicroformas de A. laidlawii nanocélulas. El cultivo de A. laidlawii PG8 adaptado in vitro a condiciones desfavorables del crecimiento muestra más evidente fitopatogenicidad que el inadaptado. Plantas infectadas V. minor L. por el cultivo del A. laidlawii PG8 adaptado in vitro a UGC dio como resultado la aparición de clorosis en el 75%, necrosis en el 50%, marcescencia de las hojas en el 50% y anormalidades del desarrollo del bine en el 30% de plantas a los 12 días, mientras que las plantas infectadas por el cultivo del A. laidlawii PG8 inadaptado a UGC, condujo a dichos signos en

  10. Defining conditions of garnet growth across the central and southern Menderes Massif, western Turkey

    Science.gov (United States)

    Etzel, T. M.; Catlos, E. J.; Kelly, E. D.; Cemen, I.; Ozerdem, C.; Atakturk, K. R.

    2017-12-01

    Here we apply thermodynamic modeling using Theriak-Domino to garnet-bearing rocks from the central and southern portions of the Menderes Massif to gain insight into the dynamics of western Turkey as the region experienced a transition from collisional to extensional tectonics. To this end, we report new pressure-temperature (P-T) paths from garnet-bearing rocks collected along the Alasehir detachment fault, a prominent exhumation structure in the central portion of the Menderes Massif in western Turkey, constituting the southern margin of the Alasehir Graben. These paths are compared to those from the Selimiye shear zone in the Southern (Cine) Massif. Two Alasehir garnets collected from the same outcrop record two P-T paths: 1) a prograde path beginning at 565oC and 6.4 kbar increasing to 592 oC and 7.5 kbar; and 2) near isobaric growth initiating at 531oC and 7.1 kbar and terminating at 571oC and 7.3 kbar. High-resolution P-T paths could not be modeled for the majority of Alasehir samples due to diffusional modification of garnet. However, conditions were estimated by garnet isopleth thermobarometry at the point of highest spessartine content for each crystal. Calculated P-T values for this subset of samples range between 566-651oC and 6.2-6.8 kbar. Despite this broad range, these P-T conditions are consistent with what is observed in the modeled paths. Th-Pb ages of matrix monazite range from 35.8±3.0 to 20.6±2.4 Ma, suggesting metamorphism in the central Menderes Massif occurred over a 15 m.y. period. Selimiye shear zone rocks show distinct N-shaped P-T paths, suggesting garnets in the central and southern portion of the Menderes Massif record distinctly different tectonic histories.

  11. Effect of hardening on the crack growth rate of austenitic stainless steels in primary PWR conditions

    International Nuclear Information System (INIS)

    Castano, M.L.; Garcia, M.S.; Diego, G. de; Gomez-Briceno, D.; Francia, L.

    2002-01-01

    Intergranular cracking of non-sensitized materials, found in light water reactor (LWR) components exposed to neutron radiation, has been attributed to Irradiation Assisted Stress Corrosion Cracking (IASCC). Cracking of baffle former bolts, fabricated of AISI-316L and AISI-347, have been reported in some Europeans and US PWR plants. Examinations of removed bolts indicate the intergranular cracking characteristics can be associated with IASCC phenomena. Neutron radiation produce critical modifications of the microstructure and microchemical of stainless steels such hardening due to irradiation and Radiation Induce Segregation (RIS) at grain boundaries, among others. Chromium depletion at grain boundary due to RIS seems to justify the intergranular cracking of irradiated materials, both in plant and in lab tests, at high electrochemical corrosion potential (BWR-NWC environments), but it is not enough to explain cracking at low corrosion potential (BWR-HWC and PWR environments). In these latter conditions, hardening is considered a possible additional mechanism to explain the behavior of irradiated material. Radiation Hardening can be simulated in non irradiated material by mechanical deformation. Although some differences exists in the types of defects produced by radiation and mechanical deformation, it is accepted that the study of the stress corrosion behavior of unirradiated austenitic steels with different hardening levels would contribute to the understanding of IASCC mechanism. In order to evaluate the influence of hardening on the stress corrosion susceptibility of austenitic steels, crack growth rate tests with 316L and 347 stainless steels with nominal yield strengths from 500 to 900 MPa, produced by cold work are being carried out at 340 deg C in PWR conditions. Preliminary results indicate that crack propagation was obtained in the 316Lss and 347ss cold worked, even with a yield strength of 550 MPa. (authors)

  12. Synergistic use of biochar, compost and plant growth-promoting rhizobacteria for enhancing cucumber growth under water deficit conditions.

    Science.gov (United States)

    Nadeem, Sajid M; Imran, Muhammad; Naveed, Muhammad; Khan, Muhammad Y; Ahmad, Maqshoof; Zahir, Zahir A; Crowley, David E

    2017-12-01

    Limited information is available about the effectiveness of biochar with plant growth-promoting rhizobacteria (PGPR) and compost. A greenhouse study was conducted to evaluate the effect of biochar in combination with compost and PGPR (Pseudomonas fluorescens) for alleviating water deficit stress. Both inoculated and un-inoculated cucumber seeds were sown in soil treated with biochar, compost and biochar + compost. Three water levels - field capacity (D0), 75% field capacity (D1) and 50% field capacity (D2) - were maintained. The results showed that water deficit stress significantly suppressed the growth of cucumber; however, synergistic use of biochar, compost and PGPR mitigated the negative impact of stress. At D2, the synergistic use of biochar, compost and PGPR caused significant increases in shoot length, shoot biomass, root length and root biomass, which were respectively 88, 77, 89 and 74% more than in the un-inoculated control. Significant improvements in chlorophyll and relative water contents as well as reduction in leaf electrolyte leakage demonstrated the effectiveness of this approach. Moreover, the highest population of P. fluorescens was observed where biochar and compost were applied together. These results suggest that application of biochar with PGPR and/or compost could be an effective strategy for enhancing plant growth under stress. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  13. Identification and Optimal Growth Conditions of Actinomycetes Isolated From Mangrove Environment

    International Nuclear Information System (INIS)

    Ameerah Abdul Hamid; Suhaidi Ariffin; Sharifah Aminah Syed Mohamad

    2015-01-01

    Actinomycetes are classified as saprophytes that play a significant role in the breakdown of organic matters into more readily assimilable nutrients. They are also known to produce a variety of secondary metabolites, which are useful for human, veterinary medicine and agriculture applications. The optimum growth conditions of actinomycetes isolated from mangrove environment at different temperature, pH and sodium chloride (NaCl) concentration were studied. The identification of the isolates by both biochemical test and 16S rRNA analysis was also done. All isolates were grown in ISP1 medium at different temperature (25, 30, 37 and 40 degree Celsius); pH (3.5, 5, 7 and 9); and salt concentration (0, 3, 5 and 7 % w/v). The optimum temperature for KMS1 and KMH2 isolates was at 25 degree Celsius. However, the optimum temperature for PCS1 and PMH1A was at 30 and 37 degree Celsius respectively. The optimum pH was pH 7 and the most preferred NaCl concentration of all isolates was at 3 % (w/v). All isolates showed negative result for carbohydrate fermentation except for KMS1 which showed utilisation of D-Fructose sugar with acid production. Only KMS1 and PCS1 exhibited amylolytic and proteolytic activity. The isolates were successfully identified as Streptomyces variables (KMS1), Streptomyces rubrolavendulae (KMH2), Streptomyces spp. CPE333 (PCS1) and Actinomycetales bacterium (PMH1A). (author)

  14. Adenylate kinase I does not affect cellular growth characteristics under normal and metabolic stress conditions.

    Science.gov (United States)

    de Bruin, Wieke; Oerlemans, Frank; Wieringa, Bé

    2004-07-01

    Adenylate kinase (AK)-catalyzed phosphotransfer is essential in the maintenance of cellular energetic economy in cells of fully differentiated tissues with highly variable energy demand, such as muscle and brain. To investigate if AK isoenzymes have a comparable function in the energy-demand management of proliferating cells, AK1 and AK1beta were expressed in mouse neuroblastoma N2a cells and in human colon carcinoma SW480 cells. Glucose deprivation, galactose feeding, and metabolic inhibitor tests revealed a differential energy dependency for these two cell lines. N2a cells showed a faster proliferation rate and strongest coupling to mitochondrial activity, SW480 proliferation was more dependent on glycolysis. Despite these differences, ectopic expression of AK1 or AK1beta did not affect their growth characteristics under normal conditions. Also, no differential effects were seen under metabolic stress upon treatment with mitochondrial and glycolytic inhibitors in in vitro culture or in solid tumors grown in vivo. Although many intimate connections have been revealed between cell death and metabolism, our results suggest that AK1- or AK1beta-mediated high-energy phosphoryl transfer is not a modulating factor in the survival of tumor cells during episodes of metabolic crisis.

  15. Continuous aryl alcohol oxidase production under growth-limited conditions using a trickle bed reactor.

    Science.gov (United States)

    Pardo-Planas, Oscar; Atiyeh, Hasan K; Prade, Rolf A; Müller, Michael; Wilkins, Mark R

    2018-05-01

    An A. nidulans strain with a pyridoxine marker was used for continuous production of aryl alcohol oxidase (AAO) in a trickle bed reactor (TBR). Modified medium with reduced zinc, no copper, and 5 g/L ascorbic acid that reduced melanin production and increased AAO productivity under growth limited conditions was used. Two air flow rates, 0.11 L/min (0.1 vvm) and 1.1 L/min (1.0 vvm) were tested. More melanin formation and reduced protein productivity were observed with air flow rate of 1.1 L/min. Three random packings were used as support for the fungus inside the TBR column, two of which were hydrophobic and one which was hydrophilic, and three different dilution rates were tested. The use of GEA BCN 030 hydrophobic packing resulted in greater AAO yield and productivity than the other packings. Increasing dilution rates favored melanin formation and citric, lactic and succinic acid accumulation, which decreased AAO yield and productivity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Diet and weaning age affect the growth and condition of Dover sole (Solea solea L.

    Directory of Open Access Journals (Sweden)

    2005-01-01

    Full Text Available The effect of diet type (frozen Artemia biomass and two inert diets: micro-bound [MB] and micro-extruded [ME] and two weaning ages (early weaning and late weaning, 50 and 64 days after hatching, respectively were studied in Solea solea larvae. The experiment lasted 56 and 42 days for early and late weaning, respectively. The mortality results showed the highest values for late weaning (39% in the Artemia treatment. No significant differences in mortality were observed between the inert diets. The final dry weight values were higher for late weaning than for early weaning. At both weaning ages, fish receiving the same treatments had similar tendencies for dry weight and standard length. Fish fed with MB presented significantly higher dry weight and standard length, followed by ME, while the lowest values at both weaning ages were recorded for the Artemia treatment. Similar amounts of highly unsaturated fatty acid fractions among the inert diets were reflected by the absence of significant differences in the susceptibility to oxidation (thiobarbituric acid reactive substances testing; however, significant differences were found in carbohydrate, protein and lipid contents of whole-body homogenates for both early and late weaning. At the end of the experiment no significant differences in biochemical contents were observed between the two inert diets. The results of this study suggest that weaning starting on day 50 (early weaning, using a good quality inert diet, leads to higher survival, growth and fish condition.

  17. Nitrogen effects on growth and development of sunflower hybrids under agro-climatic conditions of malonate

    International Nuclear Information System (INIS)

    Nasim, W.; Ahmad, A.; Wajid, A.; Muhammad, D.

    2011-01-01

    The effect of nitrogen (N) on growth, development, yield and yield components of different sunflower (Helianthus annuus L.) hybrids was evaluated under agro-climatic conditions of Multan during spring 2008 and 2009. The experiment was laid out in a randomized complete block design with split plot arrangement having three replications, keeping cultivars in the main plots and N levels in the subplots. The net plot size was 4.2 m x 5 m. The results showed that, with increasing N rates, there was increment in the biomass, yield and yield components while the oil contents were adversely affected. However, there was high seed yield in 2008 as compared to 2009. Among sunflower hybrids, Hysun-38 gave more yield as compared to other sunflower hybrids (Hysun-33, Pioneer 64A93), while in case of N levels, 180 kg ha/sup -1/ provided higher yield than other N rates (0, 60, 120, 240 kg ha/sup -1/) in both years of study especially during 2008. (author)

  18. Experimental device for investigating the crack growth behaviour of RPV steel under BWR conditions

    International Nuclear Information System (INIS)

    Anders, D.; Ahlf, J.

    1983-01-01

    An experimental device is developed to investigate the crack growth behaviour of RPV steel specimens under service conditions. It will be installed in the experimental power station VAK-Kahl (BWR, 16 MWe). The in pile part is composed of a stable frame with a hydraulically actuated load mechanism, the specimen chain and a measuring instrumentation. The specimen chain, fastened between load mechanism and a lower fixing point at the frame, is made up of five compact tensile specimens (CT40) and the associated connecting links. Specimen strain, crack opening and temperature are measured; for neutron dose monitoring activation wires are disposed. Out of pile, in the reactor hall, the hydraulic loading system is installed. The loading force is generated by a 100 kN-material testing machine; it moves a piston in the control cylinder, which is connected to the loading bellows of the in pile section. The measuring and control equipment and a desk computer serving for data preparation and reduction is placed in the reactor control room. (Auth.)

  19. Epitaxial growth of zinc on ferritic steel under high current density electroplating conditions

    International Nuclear Information System (INIS)

    Greul, Thomas; Comenda, Christian; Preis, Karl; Gerdenitsch, Johann; Sagl, Raffaela; Hassel, Achim Walter

    2013-01-01

    Highlights: •EBSD of electroplated Zn on Fe or steel was performed. •Zn grows epitaxially on electropolished ferritic steel following Burger's orientation relation. •Surface deformation of steel leads to multiple electroplated zinc grains with random orientation. •Zn grows epitaxially even on industrial surfaces with little surface deformation. •Multiple zinc grains on one steel grain can show identical orientation relations. -- Abstract: The dependence of the crystal orientation of electrodeposited zinc of the grain orientation on ferritic steel substrate at high current density deposition (400 mA cm −2 ) during a pulse-plating process was investigated by means of EBSD (electron backscatter diffraction) measurements. EBSD-mappings of surface and cross-sections were performed on samples with different surface preparations. Furthermore an industrial sample was investigated to compare lab-coated samples with the industrial process. The epitaxial growth of zinc is mainly dependent on the condition of the steel grains. Deformation of steel grains leads to random orientation while zinc grows epitaxially on non-deformed steel grains even on industrial surfaces

  20. The effect of isolation on reproduction and growth of Pseudosuccinea columella (Pulmonata: Lymnaeidae: a snail-conditioned water experiment

    Directory of Open Access Journals (Sweden)

    Gutiérrez Alfredo

    2002-01-01

    Full Text Available A snail-conditioned water experiment was conducted in Pseudosuccinea columella to test the possible role of a chemical interaction between snails on the diminished growth and fecundity rates found for snails raised in pairs compared to those raised in complete isolation. The results permit to discard the hypothesis of an inhibition of growth and reproduction between snails due to factors released into the water.

  1. Growth, development and productivity of Jerusalem artichoke depending on plant stand in the conditions of the Republic of Karakalpakstan

    Directory of Open Access Journals (Sweden)

    Zhangabaeva A.S.

    2017-08-01

    Full Text Available the article presents the results of studying the influence of various schemes of planting seed tubers of Jerusalem artichoke on the rate of plant growth and development in the soil and climatic conditions of the Republic of Karakalpakstan. Differences in the rate of growth and development of plants are revealed, depending on the varietal features of Jerusalem artichoke and the density of their standing. The most optimal scheme for planting tubers of Jerusalem artichoke is 70x40 cm.

  2. Effect of deposition conditions on the growth rate and electrical properties of ZnO thin films grown by MOCVD

    Energy Technology Data Exchange (ETDEWEB)

    Roro, K.T.; Botha, J.R.; Leitch, A.W.R. [Department of Physics, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth 6031 (South Africa)

    2008-07-01

    ZnO thin films have been grown on glass substrates by MOCVD. The effect of deposition conditions such as VI/II molar ratio, DEZn flow rate and total reactor pressure on the growth rate and electrical properties of the films was studied. It is found that the growth rate decreases with an increase in the VI/II molar ratio. This behaviour is ascribed to the competitive adsorption of reactant species on the growth surface. The growth rate increases with an increase in DEZn flow rate, as expected. It is shown that the carrier concentration is independent of the DEZn flow rate. An increase in the total reactor pressure yields a decrease in growth rate. This phenomenon is attributed to the depletion of the gas phase due to parasitic prereactions between zinc and oxygen species at high pressure. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Determination of the rate of crystal growth from the gas phase under conditions of turbulent free convection

    Science.gov (United States)

    Alad'Ev, S. I.

    1987-04-01

    Crystal growth in vertical and horizontal cylindrical vials, with the substrate and the source serving as the vial ends, is investigated analytically, assuming that the medium consists of a binary mixture of an active and an inert gas. The active gas is made up of the gaseous products of reactions taking place at the substrate and at the source. It is shown that turbulent free convection leads to an increase in crystal growth rate. All other conditions being equal, crystal growth in vertical vials is greater than that in horizontal ones; in both cases crystal growth rate increases with the vial radius, temperature gradient in the gas phase, and gas phase density. The results are compared with experimental data on the growth of Ge crystals in the Ge-GeI4 system.

  4. Evaluating the growth parameters of soybean in response to plant growth promoting fungi under Mazandaran climate conditions

    Directory of Open Access Journals (Sweden)

    mohammad yazdani

    2016-05-01

    Full Text Available Abstract In low-input cropping systems, the natural roles of microorganisms in maintaining soil fertility may be more important than conventional system. In order to investigate the effects of plant growth promoting fungi on improvement of growth and development in soybean (cv: JK an experiment was conducted at the research farm of Sari Agricultural Sciences and Natural Resources University during the 2011-2012 growing seasons. Treatments were arranged in a factorial experiment based a completely randomized block design with three replications. The first factor was six levels of fungi: inoculation T. harzianum and AMF genus Glumus: G. mosseae, G. intraradices, and co-inoculation of T. harzianum + G. mosseae, T. harzianum + G. intraradices and non-inoculation (control. The second factor was three levels of phosphorus (0, 70 and 140 kg.ha-1 from superphosphate trip. Results showed that inoculation of T. harzianum and G. mosseae significantly had maximum chlorophyll content up to 17% and 16% at reduced phosphorus dosage (70 kg.ha-1 and conventional phosphorus dosage as compared to the control respectively. The greatest effect was recorded at reduced phosphorus dosage (70 kg.ha-1 and conventional phosphorus dosage significant increase in terms of chlorophyll content. In addition, the dry weights and chlorophyll content of soybean plants in reduced phosphorous dosage (70 kg.ha-1 and co-inoculated with T. harzianum + G. mosseae as well as conventional phosphorous dosage were significantly higher than the non-inoculated plants. In this experiment, at reduce phosphate fertilizer (P0%: 0 treatment, not affected of plant growth promoting fungi compared to control. But, reduced phosphorous dosage (70 kg.ha-1 was more affected.

  5. Growth, condition, and mortality of caribou (Rangifer tarandus groenlandicus in the Sisimiut Population, West Greenland

    Directory of Open Access Journals (Sweden)

    Vidar Holthe

    1984-05-01

    Full Text Available Growth and condition of the Sisimiut caribou was anlysed by means of mandible length, carcass weight, and back fat indices. Mandible lenght showed unchanged growth conditions since the late 1960s, and growth stops at 4 years of age. The Sisimiut caribou seems to be smaller than North American caribous, Greenlandic semi-domesticated reindeer and of same size or smaller than Scandinavian reindeer. Carcass weight showed similar results, however cow growth rate seems not to prolong sexual maturation. Back fat deposits were less than what is known from other reindeer and caribou populations. Sex and age distribution of mandibles from various materials and survival curves based on the same material shows — an uneven distribution between bulls and cows and a relatively large proportion of old cows in the bag from the last years, which seems to be caused by a light hunting pressure when the population peaked in the 1960s. Heavy natural mortality for animals born before or after a winter with unfavorable snow conditions was also showed.Vækst, kondition og dødelighed hos vildren (Rangifer tarandus groenlandicus i Sisimiut-bestanden, Vestgrønland.Abstract in Danish / Sammendrag: Vækst- og konditionsforhold for Sisimiut-vildrenbestanden i Vestgrønland er beskrevet ved hjæip af underkæbelængde, slagtevægt og rygfedt. Undersøgelsen af kæbelængde viste, at vækstforholdene havde været uforandret siden sidste halvdel af 1960-erne, at væksten standser ved 4-års alderen, samt at Sisimiut-vildrenen er mindre end de nordamerikanske caribou, Itinnera-tamrenen og på størrelse med eller mindre end skandinaviske rensdyr. Dette viste sig også ved sammenligninger af slagtevægt. Vægten af simlerne er dog ikke så ringe, at der kan iagttages nogen forsinkelse i kønsmodningen. Fedtreserverne ved indgangen til vinteren synes at være dårligere end i andre undersøgte rensdyrbestande. Køns- og aldersfordelingen blandt forskellige typer af indsamlet k

  6. Growth

    Science.gov (United States)

    John R. Jones; George A. Schier

    1985-01-01

    This chapter considers aspen growth as a process, and discusses some characteristics of the growth and development of trees and stands. For the most part, factors affecting growth are discussed elsewhere, particularly in the GENETICS AND VARIATION chapter and in chapters in PART 11. ECOLOGY. Aspen growth as it relates to wood production is examined in the WOOD RESOURCE...

  7. Crack growth behaviour of low-alloy steels for pressure boundary components under transient light water reactor operating conditions - CASTOC, Part II: WWER conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ernestova, M.; Zamboch, M. [Nuclear Research Institute, NRI, Rez (Czech Republic); Devrient, B.; Roth, A. [Framatome ANP GmbH, Erlangen (Germany); Ehrnsten, U. [VTT Industrial Systems, Espoo (Finland); Foehl, J.; Weissenberg, T. [Staatliche Materialpruefungsanstalt, MPA, Stuttgart (Germany); Gomez-Briceno, D.; Lapena, J. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, CIEMAT, Madrid (Spain); Ritter, S.; Seifert, H.P. [Paul Scherrer Institute, PSI, Villigen (Switzerland)

    2004-07-01

    One of the ageing phenomena of pressure boundary components of light water reactors (LWRs) is environmentally-assisted cracking (EAC). The project CASTOC (5. Framework Programme of the EU) was launched September 2000 with six European partners and terminated August 2003. It focused in particular on the EAC behaviour of low-alloy steels (LAS) and to some extent to weld metal, heat affected zone and the influence of an austenitic cladding. The main objective was directed to the clarification of crack growth behavior of LAS in high-temperature water due to EAC under constant load (steady-state power operation), to study the effect of transient conditions (during operation or start-up/shut-down of a plant) using their impact on time-based and cycle-based crack growth rates and to a more detailed understanding of the acting mechanisms. Autoclave tests were performed with Western and Russian type reactor pressure vessel steels under simulated boiling water reactor (BWR)/normal water chemistry (NWC) and pressurized water reactor (WWER) conditions. The investigations were performed with fracture mechanics specimens of different sizes and geometries. The applied loading comprised cyclic loads, static loads and load spectra where the static load was periodically interrupted by partial unloading. With regard to water chemistry, the oxygen content (WWER) and impurities of sulphate and chlorides (BWR) were varied beyond allowable limits for continuous operation. The current paper summarizes the most important crack growth results obtained under simulated WWER conditions. The influence of oxygen content and the effect of specimen size (C(T)25 versus C(T)50 specimens) on the crack growth rates are shown. The results are discussed in the context of the current crack growth rate curves in the corresponding nuclear codes. (authors)

  8. Crack growth behaviour of low-alloy steels for pressure boundary components under transient light water reactor operating conditions - CASTOC, Part II: WWER conditions

    International Nuclear Information System (INIS)

    Ernestova, M.; Zamboch, M.; Devrient, B.; Roth, A.; Ehrnsten, U.; Foehl, J.; Weissenberg, T.; Gomez-Briceno, D.; Lapena, J.; Ritter, S.; Seifert, H.P.

    2004-01-01

    One of the ageing phenomena of pressure boundary components of light water reactors (LWRs) is environmentally-assisted cracking (EAC). The project CASTOC (5. Framework Programme of the EU) was launched September 2000 with six European partners and terminated August 2003. It focused in particular on the EAC behaviour of low-alloy steels (LAS) and to some extent to weld metal, heat affected zone and the influence of an austenitic cladding. The main objective was directed to the clarification of crack growth behavior of LAS in high-temperature water due to EAC under constant load (steady-state power operation), to study the effect of transient conditions (during operation or start-up/shut-down of a plant) using their impact on time-based and cycle-based crack growth rates and to a more detailed understanding of the acting mechanisms. Autoclave tests were performed with Western and Russian type reactor pressure vessel steels under simulated boiling water reactor (BWR)/normal water chemistry (NWC) and pressurized water reactor (WWER) conditions. The investigations were performed with fracture mechanics specimens of different sizes and geometries. The applied loading comprised cyclic loads, static loads and load spectra where the static load was periodically interrupted by partial unloading. With regard to water chemistry, the oxygen content (WWER) and impurities of sulphate and chlorides (BWR) were varied beyond allowable limits for continuous operation. The current paper summarizes the most important crack growth results obtained under simulated WWER conditions. The influence of oxygen content and the effect of specimen size (C(T)25 versus C(T)50 specimens) on the crack growth rates are shown. The results are discussed in the context of the current crack growth rate curves in the corresponding nuclear codes. (authors)

  9. Modeling the lag period and exponential growth of Listeria monocytogenes under conditions of fluctuating temperature and water activity values.

    Science.gov (United States)

    Muñoz-Cuevas, Marina; Fernández, Pablo S; George, Susan; Pin, Carmen

    2010-05-01

    The dynamic model for the growth of a bacterial population described by Baranyi and Roberts (J. Baranyi and T. A. Roberts, Int. J. Food Microbiol. 23:277-294, 1994) was applied to model the lag period and exponential growth of Listeria monocytogenes under conditions of fluctuating temperature and water activity (a(w)) values. To model the duration of the lag phase, the dependence of the parameter h(0), which quantifies the amount of work done during the lag period, on the previous and current environmental conditions was determined experimentally. This parameter depended not only on the magnitude of the change between the previous and current environmental conditions but also on the current growth conditions. In an exponentially growing population, any change in the environment requiring a certain amount of work to adapt to the new conditions initiated a lag period that lasted until that work was finished. Observations for several scenarios in which exponential growth was halted by a sudden change in the temperature and/or a(w) were in good agreement with predictions. When a population already in a lag period was subjected to environmental fluctuations, the system was reset with a new lag phase. The work to be done during the new lag phase was estimated to be the workload due to the environmental change plus the unfinished workload from the uncompleted previous lag phase.

  10. Modeling the Lag Period and Exponential Growth of Listeria monocytogenes under Conditions of Fluctuating Temperature and Water Activity Values▿

    Science.gov (United States)

    Muñoz-Cuevas, Marina; Fernández, Pablo S.; George, Susan; Pin, Carmen

    2010-01-01

    The dynamic model for the growth of a bacterial population described by Baranyi and Roberts (J. Baranyi and T. A. Roberts, Int. J. Food Microbiol. 23:277-294, 1994) was applied to model the lag period and exponential growth of Listeria monocytogenes under conditions of fluctuating temperature and water activity (aw) values. To model the duration of the lag phase, the dependence of the parameter h0, which quantifies the amount of work done during the lag period, on the previous and current environmental conditions was determined experimentally. This parameter depended not only on the magnitude of the change between the previous and current environmental conditions but also on the current growth conditions. In an exponentially growing population, any change in the environment requiring a certain amount of work to adapt to the new conditions initiated a lag period that lasted until that work was finished. Observations for several scenarios in which exponential growth was halted by a sudden change in the temperature and/or aw were in good agreement with predictions. When a population already in a lag period was subjected to environmental fluctuations, the system was reset with a new lag phase. The work to be done during the new lag phase was estimated to be the workload due to the environmental change plus the unfinished workload from the uncompleted previous lag phase. PMID:20208022

  11. EFFECT OF POLYETHYLENE BLACK PLASTIC MULCH ON GROWTH AND YIELD OF TWO SUMMER VEGETABLE CROPS UNDER RAIN-FED CONDITIONS UNDER SEMI-ARID REGION CONDITIONS

    OpenAIRE

    Atif Y. Mahadeen

    2014-01-01

    Water use efficiency in agriculture can be enhanced by several strategies mainly by reducing evaporation from the soil surface. The mulching techniques were being used widely in irrigated crop production worldwide. The mulching techniques can be also implemented in summer vegetables production under rain-fed conditions. The current study aimed at evaluating the effect of polyethylene black plastic mulch on growth and yield of okra, Abelmoschus esculentus and summer squash, ...

  12. Effect of diet supplementation on growth and reproduction in camels under arid range conditions

    Directory of Open Access Journals (Sweden)

    Abdouli H.

    2001-01-01

    Full Text Available Eighteen pregnant dromedary females (Camelus dromedarius were used to determine the effect of concentrate supplement on growth and reproductive performances in peri-partum period. The females were divided into supplemented (n = 9; S and unsupplemented (n = 9; C experimental groups. All animals grazed, with one mature male, 7 to 8 hours per day on salty pasture rangelands. During night, they were kept in pen, where each female of group S received 4 kg per day of concentrate supplement during the last 3 months of gestation and 5 kg per day during the first 3 months post-partum. During the last 90 days of gestation daily body weight gain (DBG was at least tenfold more important in group S than in group C (775 g vs. 72 g respectively. Supplementation affected birth weight of offspring (30.3 kg vs. 23.4 kg and its DBG (806 g vs. 430 g in group S and group C respectively. During the post-partum period, females in group S gained in weight (116 g per day whereas females in group C lost more than 200 g per day. The mean post-partum interval to the first heat and the percentage of females in heat were 29.5 day and 44.4/ vs. 41.2 day and 71.4/ for the C and S groups, respectively. We conclude that under range conditions, dietary supplementation of dromedary during late pregnancy stage and post-partum period improves productive and reproductive parameters.

  13. Crack growth behaviour of low-alloy steels for pressure boundary components under transient light water reactor operating conditions - CASTOC, Part I: BWR/NWC conditions

    International Nuclear Information System (INIS)

    Ritter, S.; Seifert, H.P.; Devrient, B.; Roth, A.; Ehrnsten, U.; Ernestova, M.; Zamboch, M.; Foehl, J.; Weissenberg, T.; Gomez-Briceno, D.; Lapena, J.

    2004-01-01

    One of the ageing phenomena of pressure boundary components of light water reactors (LWR) is environmentally-assisted cracking (EAC). The project CASTOC (5. Framework Programme of the EU) was launched September 2000 with six European partners and terminated August 2003. It was focused in particular on the EAC behaviour of low-alloy steels (LAS) and to some extent to weld metal, heat affected zone and the influence of an austenitic cladding. The main objective was directed to the clarification of EAC crack growth behaviour/mechanism of LAS in high-temperature water under steady-state power operation (constant load) and transient operating conditions (e.g., start-up/shut-down, transients in water chemistry and load). Autoclave tests were performed with Western and Russian type reactor pressure vessel steels under simulated boiling water reactor (BWR)/normal water chemistry (NWC) and pressurised water reactor (VVER) conditions. The investigations were performed with fracture mechanics specimens of different sizes and geometries. The applied loading comprised cyclic loads, static loads and load spectra where the static load was periodically interrupted by partial unloading. With regard to water chemistry, the oxygen content (VVER) and impurities of sulphate and chlorides (BWR) were varied beyond allowable limits for continuous operation. The current paper summarises the most important crack growth results obtained under simulated BWR/NWC conditions. The results are discussed in the context of the current crack growth rate curves in the corresponding nuclear codes. (authors)

  14. Crack growth behaviour of low-alloy steels for pressure boundary components under transient light water reactor operating conditions - CASTOC, Part I: BWR/NWC conditions

    Energy Technology Data Exchange (ETDEWEB)

    Ritter, S.; Seifert, H.P. [Paul Scherrer Institute, PSI, Villigen (Switzerland); Devrient, B.; Roth, A. [Framatome ANP GmbH, Erlangen (Germany); Ehrnsten, U. [VTT Industrial Systems, Espoo (Finland); Ernestova, M.; Zamboch, M. [Nuclear Research Institute, NRI, Rez (Czech Republic); Foehl, J.; Weissenberg, T. [Staatliche Materialpruefungsanstalt, MPA, Stuttgart (Germany); Gomez-Briceno, D.; Lapena, J. [Centro de Investigaciones Energeticas Medioambientales y Tecnologicas, CIEMAT, Madrid (Spain)

    2004-07-01

    One of the ageing phenomena of pressure boundary components of light water reactors (LWR) is environmentally-assisted cracking (EAC). The project CASTOC (5. Framework Programme of the EU) was launched September 2000 with six European partners and terminated August 2003. It was focused in particular on the EAC behaviour of low-alloy steels (LAS) and to some extent to weld metal, heat affected zone and the influence of an austenitic cladding. The main objective was directed to the clarification of EAC crack growth behaviour/mechanism of LAS in high-temperature water under steady-state power operation (constant load) and transient operating conditions (e.g., start-up/shut-down, transients in water chemistry and load). Autoclave tests were performed with Western and Russian type reactor pressure vessel steels under simulated boiling water reactor (BWR)/normal water chemistry (NWC) and pressurised water reactor (VVER) conditions. The investigations were performed with fracture mechanics specimens of different sizes and geometries. The applied loading comprised cyclic loads, static loads and load spectra where the static load was periodically interrupted by partial unloading. With regard to water chemistry, the oxygen content (VVER) and impurities of sulphate and chlorides (BWR) were varied beyond allowable limits for continuous operation. The current paper summarises the most important crack growth results obtained under simulated BWR/NWC conditions. The results are discussed in the context of the current crack growth rate curves in the corresponding nuclear codes. (authors)

  15. Fatigue crack growth characteristics of nitrogen-alloyed type 347 stainless under operating conditions of a pressurized water reactor

    Energy Technology Data Exchange (ETDEWEB)

    Min, Ki Deuk; Hong, Seok Min; Kim, Dae Whan; Lee, Bong Sang [Korea Atomic Energy Research Institute, Nuclear Materials Safety Research Division, Daejeon (Korea, Republic of); Kim, Seon Jin [Hanyang University, Division of materials science and engineering, Seoul (Korea, Republic of)

    2017-06-15

    The fatigue crack growth behavior of Type 347 (S347) and Type 347N (S347N) stainless steel was evaluated under the operating conditions of a pressurized water reactor (PWR). These two materials showed different fatigue crack growth rates (FCGRs) according to the changes in dissolved oxygen content and frequency. Under the simulated PWR conditions for normal operation, the FCGR of S347N was lower than that of S347 and insensitive to the changes in PWR water conditions. The higher yield strength and better corrosion resistance of the nitrogen-alloyed Type 347 stainless steel might be a main cause of slower FCGR and more stable properties against changes in environmental conditions.

  16. A systematic review of the routine monitoring of growth in children of primary school age to identify growth-related conditions.

    Science.gov (United States)

    Fayter, D; Nixon, J; Hartley, S; Rithalia, A; Butler, G; Rudolf, M; Glasziou, P; Bland, M; Stirk, L; Westwood, M

    2007-06-01

    To clarify the role of growth monitoring in primary school children, including obesity, and to examine issues that might impact on the effectiveness and cost-effectiveness of such programmes. Electronic databases were searched up to July 2005. Experts in the field were also consulted. Data extraction and quality assessment were performed on studies meeting the review's inclusion criteria. The performance of growth monitoring to detect disorders of stature and obesity was evaluated against National Screening Committee (NSC) criteria. In the 31 studies that were included in the review, there were no controlled trials of the impact of growth monitoring and no studies of the diagnostic accuracy of different methods for growth monitoring. Analysis of the studies that presented a 'diagnostic yield' of growth monitoring suggested that one-off screening might identify between 1:545 and 1:1793 new cases of potentially treatable conditions. Economic modelling suggested that growth monitoring is associated with health improvements [incremental cost per quality-adjusted life-year (QALY) of 9500 pounds] and indicated that monitoring was cost-effective 100% of the time over the given probability distributions for a willingness to pay threshold of 30,000 pounds per QALY. Studies of obesity focused on the performance of body mass index against measures of body fat. A number of issues relating to human resources required for growth monitoring were identified, but data on attitudes to growth monitoring were extremely sparse. Preliminary findings from economic modelling suggested that primary prevention may be the most cost-effective approach to obesity management, but the model incorporated a great deal of uncertainty. This review has indicated the potential utility and cost-effectiveness of growth monitoring in terms of increased detection of stature-related disorders. It has also pointed strongly to the need for further research. Growth monitoring does not currently meet all NSC

  17. Differential Protein Expression in Streptococcus uberis under Planktonic and Biofilm Growth Conditions ▿ †

    Science.gov (United States)

    Crowley, R. C.; Leigh, J. A.; Ward, P. N.; Lappin-Scott, H. M.; Bowler, L. D.

    2011-01-01

    The bovine pathogen Streptococcus uberis was assessed for biofilm growth. The transition from planktonic to biofilm growth in strain 0140J correlated with an upregulation of several gene products that have been shown to be important for pathogenesis, including a glutamine ABC transporter (SUB1152) and a lactoferrin binding protein (gene lbp; protein SUB0145). PMID:21075893

  18. Lettuce and rhizosphere microbiome responses to growth promoting Pseudomonas species under field conditions

    NARCIS (Netherlands)

    Cipriano, M.A.P.; Lupatini, M.; Santos, L.; Silva, M. da; Roesch, L.F.W.; Destefano, S.; Freitas, S.; Kuramae, E.E.

    2016-01-01

    Plant growth promoting rhizobacteria (PGPR) are well described and recommended for several crops worldwide. However, one of the most common problems in PGPR research is the difficulty in obtaining reproducible results. Furthermore, few studies have evaluated plant growth promotion and soil microbial

  19. Crack Growth Behaviour of P92 Steel Under Creep-fatigue Interaction Conditions

    Directory of Open Access Journals (Sweden)

    JING Hong-yang

    2017-05-01

    Full Text Available Creep-fatigue interaction tests of P92 steel at 630℃ under stress-controlled were carried out, and the crack propagation behaviour of P92 steel was studied. The fracture mechanism of crack growth under creep-fatigue interaction and the transition points in a-N curves were analyzed based on the fracture morphology. The results show that the fracture of P92 steel under creep-fatigue interaction is creep ductile fracture and the (Ctavg parameter is employed to demonstrate the crack growth behaviour; in addition, the fracture morphology shows that the crack growth for P92 steel under creep-fatigue interaction is mainly caused by the nucleation and growth of the creep voids and micro-cracks. Furthermore, the transition point of a-lg(Ni/Nf curve corresponds to the turning point of initial crack growth changed into steady crack growth while the transition point of (da/dN-N curve exhibits the turning point of steady creep crack growth changed into the accelerated crack growth.

  20. Conditions associated with Clostridium sporogenes growth as a surrogate for Clostridium botulinum in nonthermally processed canned butter.

    Science.gov (United States)

    Taylor, R H; Dunn, M L; Ogden, L V; Jefferies, L K; Eggett, D L; Steele, F M

    2013-05-01

    The objective of this study was to better understand the effect of butter composition and emulsion structure on growth and survival of Clostridium sporogenes, used as a surrogate for C. botulinum in canned butter. The lack of a thermal process step in commercially available canned butter raises questions of potential safety, because it is hermetically sealed and generally exhibits anaerobic growth conditions, which are optimal for Clostridium botulinum growth. Without thermal processing, low-acid canned foods must have inhibitory factors present to prevent C. botulinum growth. Some potential intrinsic inhibitory factors, or hurdles, within butter include: reduced water activity, acidity in cultured products, elevated salt content, and the micro-droplet nature of the aqueous phase in the butter emulsion. It was hypothesized that a normal, intact butter emulsion would have sufficient hurdles to prevent C. botulinum growth, whereas a broken butter emulsion would result in a coalesced aqueous phase that would allow for C. botulinum growth. Batch-churned butter was inoculated with C. sporogenes; butter samples with varying salt contents (0, 0.8, 1.6, and 2.4% wt/wt NaCl) were prepared and stored in coated steel cans for varying times (1 or 2 wk) and temperatures (22 or 41°C) to determine temperature and emulsion structure effects on C. sporogenes growth. Samples stored at 41°C showed a significant increase in C. sporogenes growth compared with those stored at 22°C. Furthermore, NaCl addition was found to have a significant effect on C. sporogenes growth, with 0.8% NaCl promoting more growth than 0%, but with decreases in growth observed at 1.6 and 2.4%. Uninoculated control plates were also found to have bacterial growth; this growth was attributed to other anaerobic bacteria present within the cream. It was concluded that removal of the hurdle created by the micro-droplet size of the emulsion aqueous phase could result in C. botulinum growth even at elevated salt

  1. Growth kinetics of vertically aligned carbon nanotube arrays in clean oxygen-free conditions.

    Science.gov (United States)

    In, Jung Bin; Grigoropoulos, Costas P; Chernov, Alexander A; Noy, Aleksandr

    2011-12-27

    Vertically aligned carbon nanotubes (CNTs) are an important technological system, as well as a fascinating system for studying basic principles of nanomaterials synthesis; yet despite continuing efforts for the past decade many important questions about this process remain largely unexplained. We present a series of parametric ethylene chemical vapor deposition growth studies in a "hot-wall" reactor using ultrapure process gases that reveal the fundamental kinetics of the CNT growth. Our data show that the growth rate is proportional to the concentration of the carbon feedstock and monotonically decreases with the concentration of hydrogen gas and that the most important parameter determining the rate of the CNT growth is the production rate of active carbon precursor in the gas phase reaction. The growth termination times obtained with the purified gas mixtures were strikingly insensitive to variations in both hydrogen and ethylene pressures ruling out the carbon encapsulation of the catalyst as the main process termination cause.

  2. On the influence of abiotic stress conditions on growth of barley and bean and their predisposition for pathogens

    Energy Technology Data Exchange (ETDEWEB)

    Oerke, E.C.; Schoenbeck, F.

    1986-01-01

    Shorttime changes of environmental conditions stressed barley and bean and affected plant growth and their predisposition for various pathogens. Moderate stress intensities as low or high temperatures, water or light deficits, increased the susceptibility to Erysiphe graminis var. hordei or Uromyces phaseoli and reduced disease level of spot blotch caused by Cochliobolus sativus, respectively. There was only little effect on plant growth in that case. Intensive stress as a result of combinations of unfavorable environmental conditions or longtime continuance of moderate stress reduced the plant growth and turned the predisposing effect to the opposite: after the treatment, plants were more resistent to diseases caused by biotrophic fungi, whereas there was increased susceptibility to the perthotrophic fungus. High intensities of fertilization acted as an additional stress and intensified the plant reaction to environmental alterations. The variation of the predisposition is discussed in relation to stress intensity.

  3. Preincubation of Penicillium commune conidia under modified atmosphere conditions: Influence on growth potential as determined by an impedimetric method

    DEFF Research Database (Denmark)

    Haasum, Iben; Nielsen, Per Væggemose

    1996-01-01

    The combined effect of preincubation time, relative humidity (r.h.), headspace carbon dioxide (CO2) and oxygen (O2) on subsequent growth potential of conidia from Penicillium commune was studied using Response Surface Modelling (RSM). Native conidia were preincubated under modified atmosphere...... conditions in sealed vials for 14, 35 and 56 d. Lag time and growth rates were determined using impedance microbiology on a Bactometer. Conidia survived and some swelling was observed during all experimental preincubation conditions. Regression analysis of the subsequent growth responses showed that relative...... humidity in the vials was the most significant factor affecting lag time of the conidia after preincubation for 14 and 35 d. Storage for 35 d extended lag times by 15 h when the level of r.h. was increased from 41% to 80%. After prolonged storage (56 d) r.h and CO2 levels elicited a significant effect...

  4. In-Pile Tests for IASCC Growth Behavior of Irradiated 316L Stainless Steel under Simulated BWR Condition in JMTR

    Science.gov (United States)

    Chimi, Yasuhiro; Kasahara, Shigeki; Ise, Hideo; Kawaguchi, Yoshihiko; Nakano, Junichi; Nishiyama, Yutaka

    The Japan Atomic Energy Agency (JAEA) has an in-pile irradiation test plan to evaluate in-situ effects of neutron/γ-ray irradiation on stress corrosion crack (SCC) growth of irradiated stainless steels using the Japan Materials Testing Reactor (JMTR). SCC growth rate and its dependence on electrochemical corrosion potential (ECP) are different between in-pile test and post irradiation examination (PIE). These differences are not fully understood because of a lack of in-pile data. This paper presents a systematic review on SCC growth data of irradiated stainless steels, an in-pile test plan for crack growth of irradiated SUS316L stainless steel under simulated BWR conditions in the JMTR, and the development of the in-pile test techniques.

  5. Canopy structure and tree condition of young, mature, and old-growth Douglas-fir/hardwood forests

    Science.gov (United States)

    B.B. Bingham; J.O. Sawyer

    1992-01-01

    Sixty-two Douglas-fir/hardwood stands ranging from 40 to 560 years old were used to characterize the density; diameter, and height class distributions of canopy hardwoods and conifers in young (40 -100 yr), mature (101 - 200 yr) and old-growth (>200 yr) forests. The crown, bole, disease, disturbance, and cavity conditions of canopy conifers and hardwoods were...

  6. Growth of sterlet Acipenser ruthenus under experimental and farm conditions of the Czech Republic, with remarks on other sturgeons

    Czech Academy of Sciences Publication Activity Database

    Prokeš, Miroslav; Baruš, Vlastimil; Mareš, J.; Peňáz, Milan; Baránek, V.

    2011-01-01

    Roč. 59, č. 6 (2011), s. 281-290 ISSN 1211-8516 R&D Projects: GA MZe QH71305 Institutional research plan: CEZ:AV0Z60930519 Keywords : sterlet juveniles and adults * specific growth rate * length-weight relationship * condition factor Subject RIV: GL - Fishing http://www.mendelu.cz/dok_server/slozka.pl?id=51329;download=85841

  7. Impact of Growth Conditions and Suspension Time on Toxin Release from M. aeruginosa Upon Exposure to Potassium Permanganate

    Science.gov (United States)

    The objective of this work was to assess the effects of KMnO4 on pure cultures of cyanobacteria (Microcystis aeruginosa) in a jar test. Of particular interest was the impact this oxidant has on the release of intracellular toxin from cells as a function of growth conditions in cu...

  8. Biomass and leaf-level gas exchange characteristics of three African savanna C4 grass species under optimum growth conditions

    NARCIS (Netherlands)

    Mantlana, K.B.; Veenendaal, E.M.; Arneth, A.; Grispen, V.; Bonyongo, C.M.; Heitkönig, I.M.A.; Lloyd, J.

    2009-01-01

    C4 savanna grass species, Digitaria eriantha, Eragrostis lehmanniana and Panicum repens, were grown under optimum growth conditions with the aim of characterizing their above- and below-ground biomass allocation and the response of their gas exchange to changes in light intensity, CO2 concentration

  9. Growth and Chemical Composition of Pistachio Seedlings under Different Levels of Manganese in Greenhouse Conditions

    Directory of Open Access Journals (Sweden)

    T. Poorbafrani

    2016-09-01

    Full Text Available Introduction: Pistachio is one of the most important crops in many regions of Iran with respect of production and export. There are more than 470000 ha of nonbearing and bearing pistachio trees mainly in Kerman province. Despite the economic importance of this crop, very little information is available on its nutritional requirements. Pistachio trees like other crops need to macro and micro nutrients. one of these elements is manganese (Mn. Manganese is an essential mineral nutrient, playing a key role in several physiological processes, particularly photosynthesis, respiration and nitrogen assimilation. This element is normally supplied to the plants by soil. Therefore, soil conditions affect its availability to plants. Soils with high pH, calcareous soils, especially those with poor drainage and high organic matter, are among the soils which produce Mn-deficient plants. Calcium carbonate is the major inactivation factor of Mn in calcareous soils. The soils of Iran are predominantly calcareous in which micronutrients deficiency, including Mn, is observed due to the high pH and nutrient fixation. The objective of this research was to examine the effect of manganese application on growth and chemical composition of pistachio seedlings in some calcareous soils with different chemical and physical properties. Materials and Methods: For this purpose a greenhouse experiment was carried out as factorial (two factors including soil type and Mn levels experiment in completely randomized design with three replications. Treatments were consisted of three levels of Mn (0, 10 and 20 mg Mn Kg-1 soil as Manganese sulfate and 12 different soils from Rafsanjan region in Southern Iran. Soil samples were air dried and crushed to pass through a 2-mm sieve, and some physical and chemical properties of soils such as texture, electrical conductivity, pH, organic matter content, calcium carbonate equivalent, cation exchange capacity and iron, manganese, copper and

  10. Propagule pressure, habitat conditions and clonal integration influence the establishment and growth of an invasive clonal plant, Alternanthera philoxeroides

    Directory of Open Access Journals (Sweden)

    Wen-Hua eYou

    2016-05-01

    Full Text Available Many notorious invasive plants are clonal, spreading mainly by vegetative propagules. Propagule pressure (the number of propagules may affect the establishment, growth and thus invasion success of these clonal plants, and such effects may also depend on habitat conditions. To understand how propagule pressure, habitat conditions and clonal integration affect the establishment and growth of the invasive clonal plants, an 8-week greenhouse with an invasive clonal plant, Alternanthera philoxeroides was conducted. High (five fragments or low (one fragment propagule pressure was established either in bare soil (open habitat or dense native vegetation of Jussiaea repens (vegetative habitat, with the stolon connections either severed from or connected to the relatively older ramets. High propagule pressure greatly increased the establishment and growth of A. philoxeroides, especially when it grew in vegetative habitats. Surprisingly, high propagule pressure significantly reduced the growth of individual plants of A. philoxeroides in open habitats, whereas it did not affect the individual growth in vegetative habitats. A shift in the intraspecific interaction on A. philoxeroides from competition in open habitats to facilitation in vegetative habitats may be the main reason. Moreover, clonal integration significantly improved the growth of A. philoxeroides only in open habitats, especially with low propagule pressure, whereas it had no effects on the growth and competitive ability of A. philoxeroides in vegetative habitats, suggesting that clonal integration may be of most important for A. philoxeroides to explore new open space and spread. These findings suggest that propagule pressure may be crucial for the invasion success of A. philoxeroides, and such an effect also depends on habitat conditions.

  11. Soybean growth responses to enhanced levels of ultraviolet-B radiation under greenhouse conditions

    International Nuclear Information System (INIS)

    Teramura, A.H.; Sullivan, J.H.

    1987-01-01

    Soybean (Glycine max [L.] Merr. cv. Essex) was grown in an unshaded greenhouse under three levels of biologically effective ultraviolet-B (UV-BBE) radiation (effective daily dose: 0, 11.5 and 13.6 kJ m -2 ) for 91 days. Plants were harvested at regular intervals beginning 10 days after germination until reproductive maturity. Mathematical growth analysis revealed that the effects of UV-B radiation varied with plant growth stage. The transition period between vegetative and reproductive growth was the most sensitive to UV-B radiation. Intermediate levels of UV-B had deleterious effects on plant height, leaf area, and total plant dry weight at late vegetative and reproductive stages of development. Specific leaf weight increased during vegetative growth but was unaffected by UV-B during reproductive growth stages. Relative growth, net assimilation, and stem elongation rates were decreased by UV-B radiation during vegetative and early reproductive growth stages. Variation in plant responses may be due in part to changes in microclimate within the plant canopy or to differences in repair or protection mechanisms at differing developmental stages. (author)

  12. Temperature and pH conditions for mycelial growth of Agaricus brasiliensis on axenic cultivation

    OpenAIRE

    Colauto, Nelson Barros; Universidade Paranaense; Aizono, Patrícia Midori; Universidade Paranaense; Carvalho, Lis Ribeiro Magalhães de; Universidade Paranaense; Paccola-Meirelles, Luzia Doretto; Universidade Estadual de Londrina; Linde, Giani Andrea; Universidade Paranaense

    2008-01-01

    Few studies have been done to determine Agaricus brasiliensis Wasser et al. (A. blazei; A. subrufescens) basic mycelial growth characteristics on axenic cultivation. This study aimed to determine the optimal temperature and initial pH for mycelial growth of A. brasiliensis on malt extract agar medium to develop axenic cultivation techniques. Studied initial pH values for mycelial growth were adjusted to 3.0, 4.0, 5.0, 5.5, with HCl, 6.0, 7.0, 8.0, with NaOH, and again 7.0 and 8.0, with CaCO3....

  13. Growth Protocols for Etiolated Soybeans Germinated within BRIC-60 Canisters Under Spaceflight Conditions

    Science.gov (United States)

    Levine, H. G.; Sharek, J. A.; Johnson, K. M.; Stryjewski, E. C.; Prima, V. I.; Martynenko, O. I.; Piastuch, W. C.

    As part of the GENEX (Gene Expression) spaceflight experiment, protocols were developed to optimize the inflight germination and subsequent growth of 192 soybean (Glycine max cv McCall) seeds during STS-87. We describe a method which provided uniform growth and development of etiolated seedlings while eliminating root and shoot restrictions for short-term (4-7 day) experiments. Final seedling growth morphologies and the gaseous CO2 and ethylene levels present both on the last day in space and at the time of recovery within the spaceflight and ground control BRIC-60 canisters are presented

  14. Effects of environmental conditions on growth and survival of Salmonella in pasteurized whole egg

    DEFF Research Database (Denmark)

    Jakociune, Dziuginta; Bisgaard, Magne; Hervé, Gaëlle

    2014-01-01

    This study investigated the influence of three parameters (time, temperature and NaCl concentration) on survival and four parameters (temperature, NaCl and lysozyme concentrations and pH) on growth of Salmonella enterica serovar Enteritidis (S. Enteritidis) in pasteurized whole egg (PWE). Doehlert......Cl at a fixed heating time of 120s, while maximum growth rate was estimated at 25°C and 0% of NaCl. pH and lysozyme concentration were shown not to influence growth performance significantly in the range of values studied. Results inform industry of the optimal pasteurization and storage parameters for liquid...

  15. Salmon on the Edge: Growth and Condition of Juvenile Chum and Pink Salmon in the Northeastern Bering Sea

    Science.gov (United States)

    McPhee, M. V.

    2016-02-01

    As the Arctic and Subarctic regions warm, Pacific salmon (Oncorhynchus spp.) are expected to expand their range northward during ice-free periods in the Bering and Chukchi seas. The oscillating control hypothesis, which describes energetic differences of primary consumers between ice-associated and pelagic production phases, provides a framework for understanding how juvenile salmon might respond to changing conditions at the northern edge of their marine range. Additionally, relationships between growth/condition and temperature, salinity and bottom depth will help identify marine habitats supporting growth at the Arctic-Subarctic interface. In this study, we used survey data from NOAA and Arctic Ecosystem Integrated Survey project to 1) compare growth and condition of juvenile pink (O. gorbuscha) and chum (O. keta) salmon in the NE Bering Sea between warm and cool spring phases, and 2) describe relationships between summer environmental conditions and juvenile salmon growth and condition from 2006 - 2010. Chum and pink salmon were shorter, and chum salmon exhibited greater energy density, in years with cool springs; however, no other aspects of size and condition differed significantly between phases. Over all years, longer and more energy dense individuals of both species were caught at stations with greater bottom depths and in cooler sea-surface temperatures. We found little evidence that chlorophyll-a explained much of the variation in size or condition. We used insulin-like growth factor-1 (IGF-1) concentration as an indicator of relative growth rate for fishes sampled in 2009-2012 and that found juvenile salmon exhibited higher IGF-1 concentrations in 2010-2012 than in 2009. IGF-1 concentrations tended to increase with SST in chum salmon and with bottom depth (a proxy for distance from shore) in pink salmon, but more years of data are needed to adequately describe the relationship of IGF with environmental conditions. This study, although descriptive in

  16. Fecundity, survival, and growth of the seahorse Hippocampus ingens (Pisces: Syngnathidae under semi-controlled conditions

    Directory of Open Access Journals (Sweden)

    A.A Ortega-Salas

    2006-12-01

    Full Text Available Estudiamos la fecundidad, supervivencia, y crecimiento del caballito de mar, Hippocampus ingens en condiciones semi-controladas. Tres machos reproductores silvestres de 14.8, 24.5 y 32.0 g produjeron 1 598, 1 703 y 1 658 jóvenes. La densidad utilizada fue de 12 jóvenes por acuario de 60 l. Se agruparon en 1, 12 y 20 días de nacidos por acuario. La supervivencia fue de 78.5, 38.1 y 41.0 % en 35 días. Se les alimentó con una mezcla de rotíferos B. plicatilis y nauplios de Artemia para después transferirlos a estanques de 100 000 l a una densidad de 50/1 000 l, donde se les alimentó con Artemia adulta durante 60 días más. Crecieron de un promedio de 0.7, 1.5, y 2.7 a 4.5, 5.4 6.7 cm, respectivamente, en 95 días. La temperatura del agua marina utilizada varió de 17 a 23 ºC.We studied fecundity, survival, and growth of the seahorse Hippocampus ingens under semi-controlled conditions. Three wild brood stock mature males of 14.8, 24.5, and 32.0 g released 1 598, 1 703, and 1 658 juveniles. Juvenile stocking densities of 12 were settled in 60-l aquariums in groups of 1, 12, and 20 days old organisms. The rate of survival was 21.5, 61.9, and 59.0 %, respectively, in 35 days. Juveniles were fed a mix diet of rotifers B. plicatilis and Artemia nauplii, then they were transferred to a cement tank of 100 000 l at a density of 50/1 000 l and fed with live adult Artemia for 60 days more. They grew from an average of 0.7, 1.5, and 2.7 to 4.5, 5.4, and 6.7 cm, respectively, in 95 days. The seawater temperature varied from 17 to 23 ºC. Rev. Biol. Trop. 54 (4: 1099-1102. Epub 2006 Dec. 15.

  17. Corrosion fatigue initiation and short crack growth behaviour of austenitic stainless steels under light water reactor conditions

    International Nuclear Information System (INIS)

    Seifert, H.P.; Ritter, S.; Leber, H.J.

    2012-01-01

    Highlights: ► Corrosion fatigue in austenitic stainless steels under light water reactor conditions. ► Identification of major parameters of influence on initiation and short crack growth. ► Critical system conditions for environmental reduction of fatigue initiation life. ► Comparison with the environmental factor (F env ) approach. - Abstract: The corrosion fatigue initiation and short crack growth behaviour of different wrought low-carbon and stabilised austenitic stainless steels was characterised under simulated boiling water reactor and pressurised water reactor primary water conditions by cyclic fatigue tests with sharply notched fracture mechanics specimens. The special emphasis was placed to the behaviour at low corrosion potentials and, in particular, to hydrogen water chemistry conditions. The major parameter effects and critical conjoint threshold conditions, which result in relevant environmental reduction and acceleration of fatigue initiation life and subsequent short crack growth, respectively, are discussed and summarised. The observed corrosion fatigue behaviour is compared with the fatigue evaluation procedures in codes and regulatory guidelines.

  18. Analysis of grain growth process in melt spun Fe-B alloys under the initial saturated grain boundary segregation condition

    International Nuclear Information System (INIS)

    Chen, Z.; Liu, F.; Yang, X.Q.; Fan, Y.; Shen, C.J.

    2012-01-01

    Highlights: → We compared pure kinetic, pure thermodynamic and extended thermo-kinetic models. → An initial saturated GB segregation condition of nanoscale Fe-B alloys was determined. → The controlled-mechanism was proposed using two characteristic times (t 1 and t 2 ). - Abstract: A grain growth process in the melt spun low-solid-solubility Fe-B alloys was analyzed under the initial saturated grain boundary (GB) segregation condition. Applying melt spinning technique, single-phase supersaturated nanograins were prepared. Grain growth behavior of the single-phase supersaturated nanograins was investigated by performing isothermal annealing at 700 deg. C. Combined with the effect of GB segregation on the initial GB excess amount, the thermo-kinetic model [Chen et al., Acta Mater. 57 (2009) 1466] was extended to describe the initial GB segregation condition of nanoscale Fe-B alloys. In comparison of pure kinetic model, pure thermodynamic model and the extended thermo-kinetic model, an initial saturated GB segregation condition was determined. The controlled-mechanism of grain growth under initial saturated GB segregation condition was proposed using two characteristic annealing times (t 1 and t 2 ), which included a mainly kinetic-controlled process (t ≤ t 1 ), a transition from kinetic-mechanism to thermodynamic-mechanism (t 1 2 ) and pure thermodynamic-controlled process (t ≥ t 2 ).

  19. Growth and microcystin production of a Brazilian Microcystis aeruginosa strain (LTPNA 02 under different nutrient conditions

    Directory of Open Access Journals (Sweden)

    Stella Bortoli

    Full Text Available Cyanobacteria are prokaryotic and photosynthetic organisms, which can produce a wide range of bioactive compounds with different properties; including a variety of toxic compounds, also known as cyanotoxins. In this work, we describe the isolation of seven cyanobacterial strains from two reservoirs in São Paulo State, Brazil. Seven different chemical variants of microcystins (MC-RR, MC-LR, MC-YR, MC-LF, MC-LW, and two demethylated variants, dm-MC-RR and dm-MC-LR were detected in three of the ten isolated strains. One particular Microcystis aeruginosa strain (LTPNA 02 was chosen to evaluate its growth by cell count, and its toxin production under seven different nutritional regimes. We observed different growth behaviors in the logarithmic growth period for only three experiments (p < 0.05. The total growth analysis identified four experiments as different from the control (p < 0.01. Three microcystin variants (MC-RR, MC-LR and MC-YR were quantified by liquid chromatography-tandem mass spectrometry. At the experimental end, the toxin content was unchanged when comparing cell growth in ASM-1 (N:P = 1, MLA and BG-11 (N:P = 10 medium. In all other experiments, the lowest microcystin production was observed from cells grown in Bold 3N medium during the exponential growth phase. The highest microcystin content was observed in cultures using BG-11(N:P = 100 medium.

  20. Housing conditions affecting interior moisture levels: links to mould growth and children's respiratory health

    Energy Technology Data Exchange (ETDEWEB)

    Wells, John A. [Crosier Kilgour and Partners Ltd. (Canada)], email: john.w@ckpeng.com; Polyzois, Dimos [Department of Civil Engineering, University of Manitoba (Canada)], email: polyzoi@cc.umanitoba.ca; Polyzoi, Eleoussa [Faculty of Education, University of Winnipeg (Canada)], email: l.polyzoi@uwinnipeg.ca

    2011-07-01

    Previous research has demonstrated that a person's respiratory health is affected by high indoor moisture content in their house. The aim of this paper is to provide a better understanding of the link between housing conditions and respiratory health, so that strategies can be implemented to improve the quality of life of children. This study was carried out through the completion of a survey by 3,423 parents in Winnipeg, Canada, the collection of 715 air samples from the residences of 715 parents, and an engineering audit of their homes. This study showed that a strong relationship exists between building moisture content and common home maintenance and that routine maintenance is efficient in significantly reducing the growth of mould which impacts children's respiratory health. This paper provided useful information on the relation between housing conditions and respiratory health problems and the rest of the study will aim at determining which building conditions impact mould growth most.

  1. Abscisic acid regulates root growth under osmotic stress conditions via an interacting hormonal network with cytokinin, ethylene and auxin.

    Science.gov (United States)

    Rowe, James H; Topping, Jennifer F; Liu, Junli; Lindsey, Keith

    2016-07-01

    Understanding the mechanisms regulating root development under drought conditions is an important question for plant biology and world agriculture. We examine the effect of osmotic stress on abscisic acid (ABA), cytokinin and ethylene responses and how they mediate auxin transport, distribution and root growth through effects on PIN proteins. We integrate experimental data to construct hormonal crosstalk networks to formulate a systems view of root growth regulation by multiple hormones. Experimental analysis shows: that ABA-dependent and ABA-independent stress responses increase under osmotic stress, but cytokinin responses are only slightly reduced; inhibition of root growth under osmotic stress does not require ethylene signalling, but auxin can rescue root growth and meristem size; osmotic stress modulates auxin transporter levels and localization, reducing root auxin concentrations; PIN1 levels are reduced under stress in an ABA-dependent manner, overriding ethylene effects; and the interplay among ABA, ethylene, cytokinin and auxin is tissue-specific, as evidenced by differential responses of PIN1 and PIN2 to osmotic stress. Combining experimental analysis with network construction reveals that ABA regulates root growth under osmotic stress conditions via an interacting hormonal network with cytokinin, ethylene and auxin. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

  2. Predicting plant performance under simultaneously changing environmental conditions – the interplay between temperature, light and internode growth

    Directory of Open Access Journals (Sweden)

    Katrin eKahlen

    2015-12-01

    Full Text Available Plant performance is significantly influenced by prevailing light and temperature conditions during plant growth and development. For plants exposed to natural fluctuations in abiotic environmental conditions it is however laborious and cumbersome to experimentally assign any contribution of individual environmental factors to plant responses. This study aimed at analyzing the interplay between light, temperature and internode growth based on model approaches. We extended the light-sensitive virtual plant model L-Cucumber by implementing a common Arrhenius function for appearance rates, growth rates and growth durations. For two greenhouse experiments, the temperature-sensitive model approach resulted in a precise prediction of cucumber mean internode lengths and number of internodes, as well as in accurately predicted patterns of individual internode lengths along the main stem. In addition, a system’s analysis revealed that environmental data averaged over the experimental period were not necessarily related to internode performance. Finally, the need for a species-specific parameterization of the temperature response function and related aspects in modelling temperature effects on plant development and growth is discussed.

  3. Ge deposition on Si(1 0 0) in the conditions close to dynamic equilibrium between islands growth and their decay

    International Nuclear Information System (INIS)

    Shklyaev, A.A.; Budazhapova, A.E.

    2016-01-01

    Graphical abstract: - Highlights: • Solid source MBE is used for island growth by Ge deposition on Si(1 0 0) at 700–900 °C. • Islands acquire a monomodal size distribution at temperatures above 800 °C. • Islands form ordered arrays during Ge deposition at 900 °C. • Conditions close to dynamic equilibrium are realized for growth and decay of islands at 900 °C. • Shape of ordered islands is cone with shallow sidewalls. - Abstract: The formation of islands arrays during Ge deposition on Si(1 0 0) at high temperatures is studied using scanning tunneling and electron microscopies. It is found that the island size and shape distributions, which are known to be bimodal at growth temperatures below 700 °C, become monomodal at temperatures above 800 °C. The obtained data suggest that the processes such as island nucleation and Ostwald ripening become less significant in the surface morphology formation, giving the advantage to selective attachment of deposited Ge atoms to island sidewalls and spatially inhomogeneous Si-Ge intermixing, as the temperature increases. At 900 °C, the islands exhibit a tendency to form laterally ordered arrays when the growth conditions approach the dynamic equilibrium between the growth of islands and their decay by means of Si-Ge intermixing. The islands ordering is accompanied by their shape transformation into the cone with shallow sidewalls inclined from (1 0 0) by angles of around 10°.

  4. Positive impact of bio-stimulators on growth and physiological activity of willow in climate change conditions

    Science.gov (United States)

    Piotrowski, Krzysztof; Romanowska-Duda, Zdzisława

    2018-04-01

    The aim of this research was to evaluate the physiological activity and growth of willow (Salix viminalis L.) plants cultivated under the conditions of adverse temperature and soil moisture content, and to assess the effect of the foliar application of Biojodis (1.0%) and Asahi SL (0.03%) bio-stimulators, or a mixture of Microcistis aeruginosa MKR 0105 and Anabaena PCC 7120 cyanobacteria under such changing growth conditions. The obtained results showed different reactions to the applied constant or periodically changed temperature and soil moisture content. The plants which grew at periodically changed adverse temperature (from -5 to 40oC) or in scantily (20% m.c.) or excessively (60% m.c.) watered soils, grew slowly, in comparison with those growing at 20oC and in optimally moistened soil (30% m.c.). Foliar application of Biojodis and Asahi SL cyanobacteria increased the growth of willow at optimal and adverse temperature or in scantily and excessively moistened soil. The changes in plant growth were associated with the changes in electrolyte leakage, activity of acid or alkaline phosphatases, RNase, index of chlorophyll content in leaves and gas exchange. The above indicates that the foliar application of the studied cyanobacteria and bio-stimulators partly alleviates the harmful impact of adverse temperature and water stress on growth and physiological activity of willow plants

  5. Deciphering flux adjustments of engineered E. coli cells during fermentation with changing growth conditions

    DEFF Research Database (Denmark)

    He, Lian; Xiu, Yu; Jones, J. Andrew

    2017-01-01

    Microbial fermentation conditions are dynamic, due to transcriptional induction, nutrient consumption, or changes to incubation conditions. In this study, 13C-metabolic flux analysis was used to characterize two violacein-producing E. coli strains with vastly different productivities...

  6. Inoculation of Brassica oxyrrhina with plant growth promoting bacteria for the improvement of heavy metal phytoremediation under drought conditions.

    Science.gov (United States)

    Ma, Ying; Rajkumar, Mani; Zhang, Chang; Freitas, Helena

    2016-12-15

    The aim of this study was to investigate the effects of drought resistant serpentine rhizobacteria on plant growth and metal uptake by Brassica oxyrrhina under drought stress (DS) condition. Two drought resistant serpentine rhizobacterial strains namely Pseudomonas libanensis TR1 and Pseudomonas reactans Ph3R3 were selected based on their ability to stimulate seedling growth in roll towel assay. Further assessment on plant growth promoting (PGP) parameters revealed their ability to produce indole-3-acetic acid, siderophore and 1-aminocyclopropane-1-carboxylate deaminase. Moreover, both strains exhibited high resistance to various heavy metals, antibiotics, salinity and extreme temperature. Inoculation of TR1 and Ph3R3 significantly increased plant growth, leaf relative water and pigment content of B. oxyrrhina, whereas decreased concentrations of proline and malondialdehyde in leaves under metal stress in the absence and presence of DS. Regardless of soil water conditions, TR1 and Ph3R3 greatly improved organ metal concentrations, translocation and bioconcentration factors of Cu and Zn. The successful colonization and metabolic activities of P. libanensis TR1 and P. reactans Ph3R3 represented positive effects on plant development and metal phytoremediation under DS. These results indicate that these strains could be used as bio-inoculants for the improvement of phytoremediation of metal polluted soils under semiarid conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Testing phenotypic trade-offs in the chemical defence strategy of Scots pine under growth-limiting field conditions.

    Science.gov (United States)

    Villari, Caterina; Faccoli, Massimo; Battisti, Andrea; Bonello, Pierluigi; Marini, Lorenzo

    2014-09-01

    Plants protect themselves from pathogens and herbivores through fine-tuned resource allocation, including trade-offs among resource investments to support constitutive and inducible defences. However, empirical research, especially concerning conifers growing under natural conditions, is still scarce. We investigated the complexity of constitutive and induced defences in a natural Scots pine (Pinus sylvestris L.) stand under growth-limiting conditions typical of alpine environments. Phenotypic trade-offs at three hierarchical levels were tested by investigating the behaviour of phenolic compounds and terpenoids of outer bark and phloem. We tested resource-derived phenotypic correlations between (i) constitutive and inducible defences vs tree ring growth, (ii) different constitutive defence metabolites and (iii) constitutive concentration and inducible variation of individual metabolites. Tree ring growth was positively correlated only with constitutive concentration of total terpenoids, and no overall phenotypic trade-offs between different constitutive defensive metabolites were found. At the lowest hierarchical level tested, i.e., at the level of relationship between constitutive and inducible variation of individual metabolites, we found that different compounds displayed different behaviours; we identified five different defensive metabolite response types, based on direction and strength of the response, regardless of tree age and growth rate. Therefore, under growth-limiting field conditions, Scots pine appears to utilize varied and complex outer bark and phloem defence chemistry, in which only part of the constitutive specialized metabolism is influenced by tree growth, and individual components do not appear to be expressed in a mutually exclusive manner in either constitutive or inducible metabolism. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Clostridium tyrobutyricum strains show wide variation in growth at different NaCl, pH, and temperature conditions.

    Science.gov (United States)

    Ruusunen, Marjo; Surakka, Anu; Korkeala, Hannu; Lindström, Miia

    2012-10-01

    Outgrowth from Clostridium tyrobutyricum spores in milk can lead to butyric acid fermentation in cheeses, causing spoilage and economical loss to the dairy industry. The aim of this study was to investigate the growth of 10 C. tyrobutyricum strains at different NaCl, pH, and temperature conditions. Up to 7.5-fold differences among the maximum growth rates of different strains in the presence of 2.0% NaCl were observed. Five of 10 strains were able to grow in the presence of 3.0% NaCl, while a NaCl concentration of 3.5% was completely inhibitory to all strains. Seven of 10 strains were able to grow at pH 5.0, and up to 4- and 12.5-fold differences were observed among the maximum growth rates of different strains at pH 5.5 and 7.5, respectively. The maximum growth temperatures varied from 40.2 to 43.3°C. The temperature of 10°C inhibited the growth of all strains, while 8 of 10 strains grew at 12 and 15°C. Despite showing no growth, all strains were able to survive at 10°C. In conclusion, wide variation was observed among different C. tyrobutyricum strains in their ability to grow at different stressful conditions. Understanding the physiological diversity among the strains is important when designing food control measures and predictive models for the growth of spoilage organisms in cheese.

  9. Bacillus amyloliquefaciens L-S60 Reforms the Rhizosphere Bacterial Community and Improves Growth Conditions in Cucumber Plug Seedling

    Directory of Open Access Journals (Sweden)

    Yuxuan Qin

    2017-12-01

    Full Text Available Vegetable plug seedling has become the most important way to produce vegetable seedlings in China. This seedling method can significantly improve the quality and yield of vegetables compared to conventional methods. In the process of plug seedling, chemical fertilizers or pesticides are often used to improve the yield of the seedlings albeit with increasing concerns. Meanwhile, little is known about the impact of beneficial bacteria on the rhizosphere microbiota and the growth conditions of vegetables during plug seedling. In this study, we applied a culture-independent next-generation sequencing-based approach and investigated the impact of a plant beneficial bacterium, Bacillus amyloliquefaciens L-S60, on the composition and dynamics of rhizosphere microbiota and the growth conditions of cucumbers during plug seedling. Our results showed that application of L-S60 significantly altered the structure of the bacterial community associated with the cucumber seedling; presence of beneficial rhizosphere species such as Bacillus, Rhodanobacter, Paenibacillus, Pseudomonas, Nonomuraea, and Agrobacterium was higher upon L-S60 treatment than in the control group. We also measured the impact of L-S60 application on the physiological properties of the cucumber seedlings as well as the availability of main mineral elements in the seedling at different time points during the plug seedling. Results from those measurements indicated that L-S60 application promoted growth conditions of cucumber seedlings and that more available mineral elements were detected in the cucumber seedlings from the L-S60 treated group than from the control group. The findings in this study provided evidence for the beneficial effects of plant growth-promoting rhizosphere bacteria on the bacterial community composition and growth conditions of the vegetables during plug seedling.

  10. Ultraviolet-B radiation and nitrogen effects on growth and yield of maize under Mediterranean field conditions

    OpenAIRE

    Correia, Carlos M.; Coutinho, João F.; Björn, Lars Olof; Torres-Pereira, José M. G.

    2000-01-01

    The effects of an increase in UV-B radiation on growth and yield of maize (Zea mays L.) were investigated at four levels of applied nitrogen (0, 100, 200 and 300 kg ha−1 of N) under Mediterranean field conditions. The experiment simulated a 20% stratospheric ozone depletion over Portugal. Enhanced UV-B and N deficiency decreased yield and total biomass production by 22–49%. High UV-B dose reduced yield, total biomass and growth of N-fertilized maize plants but did not affect N-stressed plants...

  11. Inoculation of Schizolobium parahyba with mycorrhizal fungi and plant growth-promoting rhizobacteria increases wood yield under field conditions

    Directory of Open Access Journals (Sweden)

    Martha Viviana Torres Cely

    2016-11-01

    Full Text Available Schizolobium parahyba var. amazonicum (Huber ex Ducke occurs naturally in the Brazilian Amazon. Currently, it is being planted extensively because of its fast growth and excellent use in forestry. Consequently, there is great interest in new strategies to increase wood production. The interaction between soil microorganisms and plants, specifically in the roots, provides essential nutrients for plant growth. These interactions can have growth-promoting effects. In this way, this study assessed the effect of the inoculation with arbuscular mycorrhizal fungi (AMF and plant growth-promoting rhizobacteria (PGPR on growth of S. parahyba var. amazonicum under field conditions. We used two native species of arbuscular mycorrhizal fungi, Claroideoglomus etunicatum (Ce and Acaulospora sp. (Ac; two native strains of Rhizobium sp. (Rh1 and Rh2; and a non-native strain of Burkholderia sp. Different combinations of microorganisms were supplemented with chemical fertilizers (doses D1 and D2 in two planting methods, seed sowing and seedling planting. In seed sowing, the results showed that treatments with Ce/Rh1/Fertilizer D2 and Ac/No PGPR/Fertilizer D2 increased wood yield. In seedling planting, two combinations (Ac/Rh2/Fertilizer D1 and Ac/Rh1/Fertilizer D1 were more effective in increasing seedling growth. In these experiments, inoculation with AMF and PGPR increased wood yield by about 20% compared to the application of fertilizer alone.

  12. Inoculation of Schizolobium parahyba with Mycorrhizal Fungi and Plant Growth-Promoting Rhizobacteria Increases Wood Yield under Field Conditions.

    Science.gov (United States)

    Cely, Martha V T; Siviero, Marco A; Emiliano, Janaina; Spago, Flávia R; Freitas, Vanessa F; Barazetti, André R; Goya, Erika T; Lamberti, Gustavo de Souza; Dos Santos, Igor M O; De Oliveira, Admilton G; Andrade, Galdino

    2016-01-01

    Schizolobium parahyba var. amazonicum (Huber ex Ducke) occurs naturally in the Brazilian Amazon. Currently, it is being planted extensively because of its fast growth and excellent use in forestry. Consequently, there is great interest in new strategies to increase wood production. The interaction between soil microorganisms and plants, specifically in the roots, provides essential nutrients for plant growth. These interactions can have growth-promoting effects. In this way, this study assessed the effect of the inoculation with arbuscular mycorrhizal fungi (AMF) and plant growth-promoting rhizobacteria (PGPR) on growth of S. parahyba var. amazonicum under field conditions. We used two native species of arbuscular mycorrhizal fungi, Claroideoglomus etunicatum (Ce), and Acaulospora sp. (Ac); two native strains of Rhizobium sp. (Rh1 and Rh2); and a non-native strain of Burkholderia sp. Different combinations of microorganisms were supplemented with chemical fertilizers (doses D1 and D2) in two planting methods, seed sowing and seedling planting. In seed sowing, the results showed that treatments with Ce/Rh1/Fertilizer D2 and Ac/No PGPR/Fertilizer D2 increased wood yield. In seedling planting, two combinations (Ac/Rh2/Fertilizer D1 and Ac/Rh1/Fertilizer D1) were more effective in increasing seedling growth. In these experiments, inoculation with AMF and PGPR increased wood yield by about 20% compared to the application of fertilizer alone.

  13. Expert Evaluation of Potential Points of Economic Growth in the Regions of Russia and the Conditions of their Development

    Directory of Open Access Journals (Sweden)

    A. V. Tihonov

    2017-01-01

    Full Text Available Purpose: the main purpose of this article is to identify « growth points» of economic growth in the regions, determine their type, and assess the conditions for their development. Methods: the main feature of this study is to obtain an expert assessment of the qualitative aspects of regional development. The main source of empirical data was an online survey conducted by the authors in 2016. Results: the study identified potential «growth points» in five regions of the Russian Federation and determined their nature according to the idea of modernizing the socio-economic environment. The selected points allow to develop the potential of the region horizontally. However, there are certain problems that hinder this development and they have been identified. Conclusions and Relevance: at the moment, the identified «growth points» can not be classified as information or intellectual, but in all regions there is the possibility of activating such industries. The «growth points» allocated by experts are still potential, because their technical, technological and innovative components have medium level of development. «Growth points» in the Republic of Sakha and the Nizhny Novgorod region have a greater modernization activity. Such expertise can be used by local authorities to adjust development vectors and strategies. It can also be an element of monitoring the socioeconomic development of regions. 

  14. Site condition, structure, and growth of baldcypress along tidal/non-tidal salinity gradients

    Science.gov (United States)

    Krauss, K.W.; Duberstein, J.A.; Doyle, T.W.; Conner, W.H.; Day, Richard H.; Inabinette, L.W.; Whitbeck, J.L.

    2009-01-01

    This report documents changes in forest structure and growth potential of dominant trees in salt-impacted tidal and non-tidal baldcypress wetlands of the southeastern United States. We inventoried basal area and tree height, and monitored incremental growth (in basal area) of codominant baldcypress (Taxodium distichum) trees monthly, for over four years, to examine the inter-relationships among growth, site fertility, and soil physico-chemical characteristics. We found that salinity, soil total nitrogen (TN), flood duration, and flood frequency affected forest structure and growth the greatest. While mean annual site salinity ranged from 0.1 to 3.4 ppt, sites with salinity concentrations of 1.3 ppt or greater supported a basal area of less than 40 m2/ha. Where salinity was < 0.7 ppt, basal area was as high as 87 m2/ha. Stand height was also negatively affected by higher salinity. However, salinity related only to soil TN concentrations or to the relative balance between soil TN and total phosphorus (TP), which reached a maximum concentration between 1.2 and 2.0 ppt salinity. As estuarine influence shifts inland with sea-level rise, forest growth may become more strongly linked to salinity, not only due to salt effects but also as a consequence of site nitrogen imbalance.

  15. Defects in silicon effect on device performance and relationship to crystal growth conditions

    Science.gov (United States)

    Jastrzebski, L.

    1985-01-01

    A relationship between material defects in silicon and the performance of electronic devices will be described. A role which oxygen and carbon in silicon play during the defects generation process will be discussed. The electronic properties of silicon are a strong function of the oxygen state in the silicon. This state controls mechanical properties of silicon efficiency for internal gettering and formation of defects in the device's active area. In addition, to temperature, time, ambience, and the cooling/heating rates of high temperature treatments, the oxygen state is a function of the crystal growth process. The incorporation of carbon and oxygen into silicon crystal is controlled by geometry and rotation rates applied to crystal and crucible during crystal growths. Also, formation of nucleation centers for oxygen precipitation is influenced by the growth process, although there is still a controversy which parameters play a major role. All these factors will be reviewed with special emphasis on areas which are still ambiguous and controversial.

  16. Maternal body size and condition determine calf growth rates in southern right whales

    DEFF Research Database (Denmark)

    Christiansen, Fredrik; Vivier, Fabien; Charlton, Claire

    2018-01-01

    The cost of reproduction is a key parameter determining a species' life history strategy. Despite exhibiting some of the fastest offspring growth rates among mammals, the cost of reproduction in baleen whales is largely unknown since standard field metabolic techniques cannot be applied. We...... quantified the cost of reproduction for southern right whales Eubalaena australis over a 3 mo breeding season. We did this by determining the relationship between calf growth rate and maternal rate of loss in energy reserves, using repeated measurements of body volume obtained from unmanned aerial vehicle...... period, and highlights the importance of sufficient maternal energy reserves for reproduction in this capital breeding species....

  17. [Effects of the nitrogen nutrition conditions on the growth and protein synthesis of carboxydobacteria].

    Science.gov (United States)

    Volova-Kesler, T G; Barashkov, V A; Trubachev, I N; Stasishina, G N

    1979-01-01

    The rate of growth of bacterial strains oxidizing carbon monoxide (Pseudomonas gazotropha Z-1156, Comamonas compransoris Z-1155, and Seliberia carboxydohydrogena Z--1062) was studied as a function of the concentration of NH4Cl in the medium. The bacteria could grow on media containing various nitrogen sources (NH4Cl, KNO3, CO(NH2)2). Changes in the amino acid content and biochemical composition of the biomass were studied during growth of the bacteria on these media. The biological value of proteins of the bacteria was estimated.

  18. Effects of Growth Conditions on the Measured Electrical Properties of Monolayer Molybdenum Disulfide

    Science.gov (United States)

    2017-02-01

    transferred via potassium hydroxide (KOH) etching to a new SiO2 substrate. Approved for public release; distribution is unlimited. 4 Samples 77C...agitation. A titanium/ gold (Ti/Au) marker layer (10 nm Ti /90 nm Au) in the shape of a coordinate grid was first deposited via electron beam evaporation... hydroxide (KOH) to separate the MoS2 from the SiO2 growth substrate. The transfer process can potentially improve performance by relaxing growth-induced

  19. Reference conditions for old-growth redwood restoration on alluvial flats

    Science.gov (United States)

    Christa M. Dagley; John-Pascal. Berrill

    2012-01-01

    We quantified structural attributes in three alluvial flat old-growth coast redwood stands. Tree size parameters and occurrences of distinctive features (e.g., burls, goose pens) were similar between stands. Occurrence of distinctive features was greater among larger trees. Tree sizefrequency distributions conformed to a reverse-J diameter distribution. The range of...

  20. Growth of the fish parasite Ichthyophonus hoferi under food relevant conditions

    DEFF Research Database (Denmark)

    Spanggaard, Bettina; Huss, Hans Henrik

    1996-01-01

    The physical and chemical limits for growth of the internal fish parasite, Ichthyophonus hoferi, have been studied to understand better the ecology of I. hoferi both as a possible food contaminant and a fish pathogen. The effect of temperature (0 degrees-30 degrees C), pH (3-7) and NaCl (0%-10%w...

  1. Removable singularities for elliptic equations with (p,q)-growth conditions

    Czech Academy of Sciences Publication Activity Database

    Namlyeyeva, Yuliya; Skrypnik, I.

    2018-01-01

    Roč. 31, 1-2 (2018), s. 95-110 ISSN 0893-4983 Institutional support: RVO:67985840 Keywords : regularity * growth * existence Subject RIV: BA - General Mathematics OBOR OECD: Pure mathematics Impact factor: 0.565, year: 2016 https://projecteuclid.org/euclid.die/1509041403#ui-tabs-1

  2. Establishment and growth of container seedlings for reforestation: A function of stocktype and edaphic conditions

    Science.gov (United States)

    Jeremiah R. Pinto; John D. Marshall; R. Kasten Dumroese; Anthony S. Davis; Douglas R. Cobos

    2011-01-01

    A properly selected stocktype can greatly enhance reforestation success through increased survival and growth following outplanting. Implementing a robust stocktype trial using stocktypes of equal quality can ensure results lead to the best choice. Six container types, differing primarily in depth and volume, were used to evaluate the performance of ponderosa pine (...

  3. Growth kinetics and long-term stability of CdS nanoparticles in aqueous solution under ambient conditions

    International Nuclear Information System (INIS)

    Mullaugh, Katherine M.; Luther, George W.

    2011-01-01

    The ubiquity of naturally occurring nanoparticles in the aquatic environment is now widely accepted, but a better understanding of the conditions that promote their formation and persistence is needed. Using cadmium sulfide (CdS) as a model metal sulfide species, thiolate-capped CdS nanoparticles were prepared in the laboratory to evaluate how aquatic conditions influence metal sulfide nanoparticle growth and stability. This work examines CdS nanoparticle growth directly in aqueous solution at room temperature by utilizing the size-dependent spectroscopic properties of semiconductors detectable by UV/vis. CdS nanoparticle growth was governed by oriented attachment, a non-classical mechanism of crystallization in which small precursor nanoparticles coalesce to form larger nanoparticle products. Nanoparticle growth was slowed with increasing capping agent and decreasing ionic strength. In addition to examining the short-term (hours) growth of the nanoparticles, a long-term study was conducted in which cysteine-capped CdS nanoparticles were monitored over 3 weeks in solutions of various ionic strengths. The long-term study revealed an apparent shift from small nanoparticles to nanoparticles twice their original size, suggesting nanoparticle growth may continue through oriented attachment over longer time scales. High-ionic strength solutions resulted in salt-induced aggregation and eventual settling of nanoparticles within days, whereas low-ionic strength solutions were stable against settling over the course of the experiment. Sulfide recovery from cysteine-capped CdS nanoparticles as acid volatile sulfide was nearly quantitative after 2 weeks in fully oxygenated water, demonstrating significantly slowed oxidation of sulfide when complexed to Cd(II) within CdS nanoparticles. The nanoparticles were also shown to be resistant to oxidation by Fe(III) (hydr)oxide. This study illustrates that aggregation, rather than chemical oxidation, is likely more important to the

  4. When bigger is not better: selection against large size, high condition and fast growth in juvenile lemon sharks.

    Science.gov (United States)

    Dibattista, J D; Feldheim, K A; Gruber, S H; Hendry, A P

    2007-01-01

    Selection acting on large marine vertebrates may be qualitatively different from that acting on terrestrial or freshwater organisms, but logistical constraints have thus far precluded selection estimates for the former. We overcame these constraints by exhaustively sampling and repeatedly recapturing individuals in six cohorts of juvenile lemon sharks (450 age-0 and 255 age-1 fish) at an enclosed nursery site (Bimini, Bahamas). Data on individual size, condition factor, growth rate and inter-annual survival were used to test the 'bigger is better', 'fatter is better' and 'faster is better' hypotheses of life-history theory. For age-0 sharks, selection on all measured traits was weak, and generally acted against large size and high condition. For age-1 sharks, selection was much stronger, and consistently acted against large size and fast growth. These results suggest that selective pressures at Bimini may be constraining the evolution of large size and fast growth, an observation that fits well with the observed small size and low growth rate of juveniles at this site. Our results support those of some other recent studies in suggesting that bigger/fatter/faster is not always better, and may often be worse.

  5. Stressful dieting: nutritional conditions but not compensatory growth elevate corticosterone levels in zebra finch nestlings and fledglings.

    Directory of Open Access Journals (Sweden)

    Mariam Honarmand

    Full Text Available Unfavourable conditions throughout the period of parental care can severely affect growth, reproductive performance, and survival. Yet, individuals may be affected differently, depending on the developmental period during which constraints are experienced. Here we tested whether the nestling phase compared to the fledgling phase is more susceptible to nutritional stress by considering biometry, physiology, sexually selected male ornaments and survival using zebra finches (Taeniopygia guttata as a model species. As nestlings (day 0-17 or fledglings (day 17-35, subjects were raised either on low or high quality food. A low quality diet resulted in significantly elevated baseline corticosterone titres in both nestlings and fledglings. Subjects showed substantial compensatory growth after they had experienced low quality food as nestlings but catch-up growth did neither lead to elevated baseline corticosterone titres nor did we detect long term effects on biometry, male cheek patch, or survival. The compensation for temporally unfavourable environmental conditions reflects substantial phenotypic plasticity and the results show that costs of catch-up growth were not mediated via corticosterone as a physiological correlate of allostatic load. These findings provide new insights into the mechanisms and plasticity with which animals respond to periods of constraints during development as they may occur in a mistiming of breeding.

  6. Media Compositions for Three-Dimensional Mammalian Tissue Growth under Microgravity Culture Conditions

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    1998-01-01

    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue.The cells are grown in vitro under microgravity culture conditions and form three dimensional cells aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  7. Media Compositions for Three Dimensional Mammalian Tissue Growth Under Microgravity Culture Conditions

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    1998-01-01

    Normal mammalian tissue and the culturing process has been developed for the three groups of organ, structural and blood tissue. The cells are grown in vitro under microgravity culture conditions and form three dimensional cells aggregates with normal cell function. The microgravity culture conditions may be microgravity or simulated microgravity created in a horizontal rotating wall culture vessel.

  8. Influence of the mycelium growth conditions on the production of amylolytic, proteolytic and pectinolytic enzymes by Aspergillus niger C

    Energy Technology Data Exchange (ETDEWEB)

    Fiedurek, J.; Ilczuk, Z.; Lobarzewski, J. (Uniwersytet Marii Curie-Sklodowskiej, Lublin (Poland). Inst. Mikrobiologii i Biochemii)

    1989-01-01

    Various nitrogen and carbon sources, as well as natural products, were examined as inducers of the production of amylases, proteases and pectinases by A. niger C. A. niger C grown on wheat bran extract medium provided culture supernatants with the highest enzymatic activities. Some culture conditions, e.g. pH, medium temperature and time period of cultivation, were optimalized to improve the growth and enzyme biosynthesis by A. niger C. (orig.).

  9. Photogrammetry with an Unmanned Aerial System to Assess Body Condition and Growth of Blainville’s Beaked Whales

    Science.gov (United States)

    2015-09-30

    Body Condition and Growth of Blainville’s Beaked Whales Diane Claridge & Charlotte Dunn Bahamas Marine Mammal Research Organisation P.O. Box...second intervals to maximize the chance of obtaining “ flat ” images for unbiased photogrammetry measurements. Multiple batteries for the hexacopter...Commanders Course using satellite telemetry This project is a collaborative project between the Bahamas Marine Mammal Research Organisation , NOAA

  10. Actual measurement, hygrothermal response experiment and growth prediction analysis of microbial contamination of central air conditioning system in Dalian, China.

    Science.gov (United States)

    Lv, Yang; Hu, Guangyao; Wang, Chunyang; Yuan, Wenjie; Wei, Shanshan; Gao, Jiaoqi; Wang, Boyuan; Song, Fangchao

    2017-04-03

    The microbial contamination of central air conditioning system is one of the important factors that affect the indoor air quality. Actual measurement and analysis were carried out on microbial contamination in central air conditioning system at a venue in Dalian, China. Illumina miseq method was used and three fungal samples of two units were analysed by high throughput sequencing. Results showed that the predominant fungus in air conditioning unit A and B were Candida spp. and Cladosporium spp., and two fungus were further used in the hygrothermal response experiment. Based on the data of Cladosporium in hygrothermal response experiment, this paper used the logistic equation and the Gompertz equation to fit the growth predictive model of Cladosporium genera in different temperature and relative humidity conditions, and the square root model was fitted based on the two environmental factors. In addition, the models were carried on the analysis to verify the accuracy and feasibility of the established model equation.

  11. A novel liquid medium for the efficient growth of the salmonid pathogen Piscirickettsia salmonis and optimization of culture conditions.

    Directory of Open Access Journals (Sweden)

    Mirtha Henríquez

    Full Text Available Piscirickettsia salmonis is the bacterium that causes Piscirickettsiosis, a systemic disease of salmonid fish responsible for significant economic losses within the aquaculture industry worldwide. The growth of the bacterium for vaccine formulation has been traditionally accomplished by infecting eukaryotic cell lines, a process that involves high production costs and is time-consuming. Recent research has demonstrated that it is possible to culture pure P. salmonis in a blood containing (cell-free medium. In the present work we demonstrate the growth of P. salmonis in a liquid medium free from blood and serum components, thus establishing a novel and simplified bacteriological medium. Additionally, the new media reported provides improved growth conditions for P. salmonis, where biomass concentrations of approximately 800 mg cell dry weight L(-1 were obtained, about eight times higher than those reported for the blood containing medium. A 2- level full factorial design was employed to evaluate the significance of the main medium components on cell growth and an optimal temperature range of 23-27°C was determined for the microorganism to grow in the novel liquid media. Therefore, these results represent a breakthrough regarding P. salmonis research in order to optimize pure P. salmonis growth in liquid blood and serum free medium.

  12. Effect of two plant growth regulators and illumination conditions in the germination of conserved seeds of Clitoria ternatea

    Directory of Open Access Journals (Sweden)

    Maribel Quintana

    2013-04-01

    Full Text Available The seeds viability lost in the seed legume bank of Research Institute of Pastures and Forages (IIPF led to the aim of the work it was to determine the effect of two plant growth regulators (gibberellic acid; GA3 and naphthalene acetic acid; ANA and illumination conditions on the germination of Clitoria ternatea SC-136 conserved seeds. One experiment was performed with two-factor completely randomized design with four replications Five different levels of growth regulators (factor A and two illumination conditions (factor B were evaluated. The variables measured were: total germination percentage (PTG and angular transformation, days to 50% PTG (G50 and the days between 10 and 90% PTG (G10-90. In addition, morphological variables were evaluated. It was found that the addition of plant growth regulators (GA3 and NAA was effective in increasing germination of Clitoria ternatea SC-136 conserved seeds, but not the illumination conditions tested. Combination GA3 (1 mg l-1 and NAA (0.1 mg l-1 to stimulate germination was recommended. Key words: GA3, germplasm, legume, NAA, photoperiod.

  13. Texture of the nano-crystalline AlN thin films and the growth conditions in DC magnetron sputtering

    Directory of Open Access Journals (Sweden)

    Shakil Khan

    2015-08-01

    Full Text Available DC reactive magnetron sputtering technique has been used for the preparation of AlN thin films. The deposition temperature and the flow ratio of N2/Ar were varied and subsequent dependency of the films crystallites orientation/texture has been addressed. In general, deposited films were found hexagonal polycrystalline with a (002 preferred orientation. The X-ray diffraction (XRD data revealed that the film crystallinity improves, with the increase of substrate temperature from 300 °C to 500 °C. The dropped in full width half maximum (FWHM of the XRD rocking curve value further confirmed it. However, increasing substrate temperature above 500 °C or reducing the nitrogen condition (from 60 to 30% in the environment induced the growth of crystallites with (102 and (103 orientations. The rise of rocking curve FWHM for the corresponding conditions depicted that the films texture quality deteriorated. A further confirmation of the variation in film texture/orentation with the growth conditions has been obtained from the variation in FWHM values of a dominant E1 (TO mode in the Fourier transform infrared (FTIR spectra and the E2 (high mode in Raman spectra. We have correlated the columnar structure in AFM surface analyses with the (002 or c-axis orientation as well. Spectroscopic ellipsometry of the samples have shown a higher refractive index at 500 °C growth temperature.

  14. Growth and decay of runaway electrons above the critical electric field under quiescent conditions

    International Nuclear Information System (INIS)

    Paz-Soldan, C.; Eidietis, N. W.; Wesley, J. C.; Granetz, R.; Hollmann, E. M.; Moyer, R. A.; Zhang, J.; Crocker, N. A.; Austin, M. E.; Wingen, A.; Zhu, Y.

    2014-01-01

    Extremely low density operation free of error field penetration supports the excitation of trace-level quiescent runaway electron (RE) populations during the flat-top of DIII-D Ohmic discharges. Operation in the quiescent regime allows accurate measurement of all key parameters important to RE excitation, including the internal broadband magnetic fluctuation level. RE onset is characterized and found to be consistent with primary (Dreicer) generation rates. Impurity-free collisional suppression of the RE population is investigated by stepping the late-time main-ion density, until RE decay is observed. The transition from growth to decay is found to occur 3–5 times above the theoretical critical electric field for avalanche growth and is thus indicative of anomalous RE loss. This suggests that suppression of tokamak RE avalanches can be achieved at lower density than previously expected, though extrapolation requires predictive understanding of the RE loss mechanism and magnitude

  15. Considerations Regarding the Decoupling Thesis under Conditions of Demographic Growth and Industrialization

    Directory of Open Access Journals (Sweden)

    Florina Bran

    2007-12-01

    Full Text Available Many individuals and organizational leaders are well aware that their activities affect the natural environment. This awareness grows out of growing evidence of the effects of environmental use and some thirty years of environmental activism. Our paper aims to look at the worldwide interconnections in the natural environment that result from the use of global commons and other resources. A special emphasis will be given to examine the combined effects of population growth and industrialization as pressures on the natural environment. Together population growth and economic development hasten natural resources consumption, putting pressure on the global commons, spreading disease, threatening species, and extending the impact of global natural disasters. Their interrelated nature will be enlightened thoroughly toward “boom” and “doom” perspectives.

  16. Existence Results for Differential Inclusions with Nonlinear Growth Conditions in Banach Spaces

    Directory of Open Access Journals (Sweden)

    Messaoud Bounkhel

    2013-01-01

    Full Text Available In the Banach space setting, the existence of viable solutions for differential inclusions with nonlinear growth; that is, ẋ(t∈F(t,x(t a.e. on I, x(t∈S, ∀t∈I, x(0=x0∈S, (*, where S is a closed subset in a Banach space , I=[0,T], (T>0, F:I×S→, is an upper semicontinuous set-valued mapping with convex values satisfying F(t,x⊂c(tx+xp, ∀(t,x∈I×S, where p∈ℝ, with p≠1, and c∈C([0,T],ℝ+. The existence of solutions for nonconvex sweeping processes with perturbations with nonlinear growth is also proved in separable Hilbert spaces.

  17. Bacteria of the Burkholderia cepacia complex are cyanogenic under biofilm and colonial growth conditions

    Directory of Open Access Journals (Sweden)

    Hoshino Saiko

    2008-06-01

    Full Text Available Abstract Background The Burkholderia cepacia complex (Bcc is a collection of nine genotypically distinct but phenotypically similar species. They show wide ecological diversity and include species that are used for promoting plant growth and bio-control as well species that are opportunistic pathogens of vulnerable patients. Over recent years the Bcc have emerged as problematic pathogens of the CF lung. Pseudomonas aeruginosa is another important CF pathogen. It is able to synthesise hydrogen cyanide (HCN, a potent inhibitor of cellular respiration. We have recently shown that HCN production by P. aeruginosa may have a role in CF pathogenesis. This paper describes an investigation of the ability of bacteria of the Bcc to make HCN. Results The genome of Burkholderia cenocepacia has 3 putative HCN synthase encoding (hcnABC gene clusters. B. cenocepacia and all 9 species of the Bcc complex tested were able to make cyanide at comparable levels to P. aeruginosa, but only when grown surface attached as colonies or during biofilm growth on glass beads. In contrast to P. aeruginosa and other cyanogenic bacteria, cyanide was not detected during planktonic growth of Bcc strains. Conclusion All species in the Bcc are cyanogenic when grown as surface attached colonies or as biofilms.

  18. Different growing conditions affect nutrient content, fruit yield and growth in strawberry

    International Nuclear Information System (INIS)

    Demirsory, L.; Demirsoy, H.; Balci, G.

    2011-01-01

    This study aimed to determine the effects of organic and conventional growing on contents of some nutrient elements, nitrogen (N), phosphorous (P), potassium (K), iron (Fe), and manganese (Mn), yield and some growth parameters such as leaf area, petiole length, petiole diameter, crown number, crow n diameter, leaf, root dry weight in 'Sweet Charlie' and 'Camarosa' strawberry cultivars. This study consisted of two strawberry cultivars ('Camarosa' and 'Sweet Charlie'), two growing systems (organic and conventional growing) and two different mulches (black and floating sheet). There was significant difference among treatments in terms of P, K, and Mn content in root and Fe content in leaf and yield and some growth parameters. The best treatment in terms of yield and growth parameters was conventional growing with black plastic in 'Camarosa' while the best treatments were organic growing with floating sheet and black plastic in 'Sweet Charlie' in terms of P, K in root and organic growing with floating sheet in 'Sweet Charlie' in terms of Fe in leaf. (author)

  19. Optimization and effects of different culture conditions on growth of Halomicronema hongdechloris – a filamentous cyanobacterium containing chlorophyll f

    Directory of Open Access Journals (Sweden)

    Yaqiong eLi

    2014-02-01

    Full Text Available A chlorophyll f containing cyanobacterium, Halomicronema hongdechloris (H. hongdechloris was isolated from a stromatolite cyanobacterial community. However, the extremely slower growth rate of H. hongdechloris culture became a critical factor, hindering the research on this newly isolated cyanobacterium and the investigation of chlorophyll f-photosynthesis. Therefore, optimizing H. hongdechloris culture conditions has become an essential requirement for future research. This work investigated the effects of various culture conditions, essential nutrients and light environments to determine the optimal growth conditions for H. hongdechloris and the biosynthetic rate of chlorophyll f. Based on the total chlorophyll concentration, an optimal growth rate of 0.22 ± 0.02 day-1 (doubling time: 3.1 ± 0.3 days was observed when cells were grown under continuous illumination with far-red light with an intensity of 20 µE at 32°C in modified K+ES seawater (pH 8.0 with additional supplements of 11.75 mM NaNO3 and 0.15 mM K2HPO4. High performance liquid chromatography on H. hongdechloris pigments confirmed that chlorophyll a is the major chlorophyll and chlorophyll f constitutes approximately 10% of the total chlorophyll from cells grown under far-red light. Fluorescence confocal image analysis demonstrated changes of photosynthetic membranes and the distribution of photopigments in response to different light conditions. The total photosynthetic oxygen evolution yield per cell showed no changes under different light conditions, which confirms the involvement of chlorophyll f in oxygenic photosynthesis. The implications of the presence of chlorophyll f in H. hongdechloris and its relationship to light environment are discussed.

  20. Uniformity of environmental conditions and plant growth in a hydroponic culture system for use in a growth room with aerial CO2 control

    Science.gov (United States)

    Vessey, J. K.; York, E. K.; Henry, L. T.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1988-01-01

    A portable system of hydroponic culture was developed that maintained temperature, pH, and nutrient concentrations of circulating nutrient solutions. The hydroponic system is used within a controlled-environment room (CER) for control of aerial environment. The CER was equipped with an auto-calibrating system for atmospheric CO2 control. The control systems for the hydroponic chambers were able to maintain acidity within +/- 0.2 pH units and the temperature with +/- 0.5 degree C. Mixing time for the 200-liter volume of solution within a hydroponic chamber was less than 12 min. The CO2 control system was able to maintain aerial concentrations within +/- 10 ppm CO2 during the light period. The only gradient found to occur within the hydroponic chambers or CER was a slight gradient in aerial temperature along the length of hydroponic chambers. Growth of soybeans [Glycine max (L.) Merr.] was characterized during a 3-week period of vegetative development by leaf number and area, plant dry weight, total N content of plants, and N depletion from the nutrient solution. The growth characteristics among populations for three hydroponic chambers within the CER were not significantly different, and the percent standard errors of means of the measurements within populations from each chamber were nearly all less than 10%. Thus, the uniformity of plant growth reflected the uniformity of environmental conditions.

  1. The influence of MOVPE growth conditions on the shell of core-shell GaN microrod structures

    Science.gov (United States)

    Schimpke, Tilman; Avramescu, Adrian; Koller, Andreas; Fernando-Saavedra, Amalia; Hartmann, Jana; Ledig, Johannes; Waag, Andreas; Strassburg, Martin; Lugauer, Hans-Jürgen

    2017-05-01

    A core-shell geometry is employed for most next-generation, three-dimensional opto-electric devices based on III-V semiconductors and grown by metal organic vapor phase epitaxy (MOVPE). Controlling the shape of the shell layers is fundamental for device optimization, however no detailed analysis of the influence of growth conditions has been published to date. We study homogeneous arrays of gallium nitride core-shell microrods with height and diameter in the micrometer range and grown in a two-step selective area MOVPE process. Changes in shell shape and homogeneity effected by deliberately altered shell growth conditions were accurately assessed by digital analysis of high-resolution scanning electron microscope images. Most notably, two temperature regimes could be established, which show a significantly different behavior with regard to material distribution. Above 900 °C of wafer carrier temperature, the shell thickness along the growth axis of the rods was very homogeneous, however variations between vicinal rods increase. In contrast, below 830 °C the shell thickness is higher close to the microrod tip than at the base of the rods, while the lateral homogeneity between neighboring microrods is very uniform. This temperature effect could be either amplified or attenuated by changing the remaining growth parameters such as reactor pressure, structure distance, gallium precursor, carrier gas composition and dopant materials. Possible reasons for these findings are discussed with respect to GaN decomposition as well as the surface and gas phase diffusion of growth species, leading to an improved control of the functional layers in next-generation 3D V-III devices.

  2. Influence of flow conditions and matrix coatings on growth and differentiation of three-dimensionally cultured rat hepatocytes.

    Science.gov (United States)

    Fiegel, Henning C; Havers, Joerg; Kneser, Ulrich; Smith, Molly K; Moeller, Tim; Kluth, Dietrich; Mooney, David J; Rogiers, Xavier; Kaufmann, Peter M

    2004-01-01

    Maintenance of liver-specific function of hepatocytes in culture is still difficult. Improved culture conditions may enhance the cell growth and function of cultured cells. We investigated the effect of three-dimensional culture under flow conditions, and the influence of surface modifications in hepatocyte cultures. Hepatocytes were harvested from Lewis rats. Cells were cultured on three-dimensional polymeric poly-lactic-co-glycolic acid (PLGA) matrices in static culture, or in a pulsatile flow-bioreactor system. Different surface modifications of matrices were investigated: coating with collagen I, collagen IV, laminin, or fibronectin; or uncoated matrix. Hepatocyte numbers, DNA content, and albumin secretion rate were assessed over the observation period. Culture under flow condition significantly enhanced cell numbers. An additional improvement of this effect was observed, when matrix coating was used. Cellular function also showed a significant increase (4- to 5-fold) under flow conditions when compared with static culture. Our data showed that culture under flow conditions improves cell number, and strongly enhances cellular function. Matrix modification by coating with extracellular matrix showed overall an additive stimulatory effect. Our conclusion is that combining three-dimensional culture under flow conditions and using matrix modification significantly improves culture conditions and is therefore attractive for the development of successful culture systems for hepatocytes.

  3. Oncolytic viruses for cancer therapy II. Cell-internal factors for conditional growth in neoplastic cells.

    Science.gov (United States)

    Campbell, Stephanie A; Gromeier, Matthias

    2005-04-01

    Recent advances in our understanding of virus-host interactions have fueled new studies in the field of oncolytic viruses. The first part of this review explained how cell-external factors, such as cellular receptors, influence tumor tropism and specificity of oncolytic virus candidates. In the second part of this review, we focus on cellinternal factors that mediate tumor-specific virus growth. An oncolytic virus must be able to replicate within cancerous cells and kill them without collateral damage to healthy surrounding cells. This desirable property is inherent to some proposed oncolytic viral agents or has been achieved by genetic manipulation in others.

  4. Applying Dynamic Energy Budget (DEB) theory to simulate growth and bio-energetics of blue mussels under low seston conditions

    Science.gov (United States)

    Rosland, R.; Strand, Ø.; Alunno-Bruscia, M.; Bacher, C.; Strohmeier, T.

    2009-08-01

    A Dynamic Energy Budget (DEB) model for simulation of growth and bioenergetics of blue mussels ( Mytilus edulis) has been tested in three low seston sites in southern Norway. The observations comprise four datasets from laboratory experiments (physiological and biometrical mussel data) and three datasets from in situ growth experiments (biometrical mussel data). Additional in situ data from commercial farms in southern Norway were used for estimation of biometrical relationships in the mussels. Three DEB parameters (shape coefficient, half saturation coefficient, and somatic maintenance rate coefficient) were estimated from experimental data, and the estimated parameters were complemented with parameter values from literature to establish a basic parameter set. Model simulations based on the basic parameter set and site specific environmental forcing matched fairly well with observations, but the model was not successful in simulating growth at the extreme low seston regimes in the laboratory experiments in which the long period of negative growth caused negative reproductive mass. Sensitivity analysis indicated that the model was moderately sensitive to changes in the parameter and initial conditions. The results show the robust properties of the DEB model as it manages to simulate mussel growth in several independent datasets from a common basic parameter set. However, the results also demonstrate limitations of Chl a as a food proxy for blue mussels and limitations of the DEB model to simulate long term starvation. Future work should aim at establishing better food proxies and improving the model formulations of the processes involved in food ingestion and assimilation. The current DEB model should also be elaborated to allow shrinking in the structural tissue in order to produce more realistic growth simulations during long periods of starvation.

  5. Temperate heath plant response to dry conditions depends on growth strategy and less on physiology

    DEFF Research Database (Denmark)

    Albert, Kristian Rost; Kongstad, J.; Schmidt, I. K.

    2012-01-01

    of these differences in response in dry versus rewetting conditions can be used to highlight the limitations coherent in different strategies adopted by, for example, evergreen shrubs and grasses. We investigated the leaf-level photosynthetic performance, leaf C, N and d13C along with vegetation cover and biomass...... in the evergreen dwarf shrub Calluna vulgaris and the grass species Deschampsia flexuosa in a temperate heath during seasonal changes in soil moisture. Higher photosynthetic capacity compensated for lower stomatal conductance and sustained higher rates of photosynthesis in the grass compared to the dwarf shrub....... In combination with dieback of aboveground biomass and reduction of stomatal conductance reduction during dry conditions, the grass continued to have high carbon uptake in the remaining leaves. The dwarf shrub endured the dry conditions by preserving shoot biomass and reducing stomatal conductance. Soil...

  6. Overexpression of PSP1 enhances growth of transgenic Arabidopsis plants under ambient air conditions.

    Science.gov (United States)

    Han, Xiaofang; Peng, Keli; Wu, Haixia; Song, Shanshan; Zhu, Yerong; Bai, Yanling; Wang, Yong

    2017-07-01

    The importance of the phosphorylated pathway (PPSB) of L-serine (Ser) biosynthesis in plant growth and development has been demonstrated, but its specific role in leaves and interaction with photorespiration, the main leaf Ser biosynthetic pathway at daytime, are still unclear. To investigate whether changes in biosynthesis of Ser by the PPSB in leaves could have an impact on photorespiration and plant growth, we overexpressed PSP1, the last enzyme of this pathway, under control of the Cauliflower Mosaic Virus 35S promoter in Arabidopsis thaliana. Overexpressor plants grown in normal air displayed larger rosette diameter and leaf area as well as higher fresh and dry weight than the wild type. By contrast, no statistically significant differences to the wild type were observed when the overexpressor seedlings were transferred to elevated CO 2 , indicating a relationship between PSP1 overexpression and photorespiration. Additionally, the transgenic plants displayed higher photorespiration, an increase in CO 2 net-uptake and stronger expression in the light of genes encoding enzymes involved in photorespiration. We further demonstrated that expression of many genes involved in nitrogen assimilation was also promoted in leaves of transgenic plants and that leaf nitrate reductase activity increased in the light, too, although not in the dark. Our results suggest a close correlation between the function of PPSB and photorespiration, and also nitrogen metabolism in leaves.

  7. Effects of environmental conditions on onset of xylem growth in Pinus sylvestris under drought.

    Science.gov (United States)

    Swidrak, Irene; Gruber, Andreas; Kofler, Werner; Oberhuber, Walter

    2011-05-01

    We determined the influence of environmental factors (air and soil temperature, precipitation, photoperiod) on onset of xylem growth in Scots pine (Pinus sylvestris L.) within a dry inner Alpine valley (750 m a.s.l., Tyrol, Austria) by repeatedly sampling micro-cores throughout 2007-10 at two sites (xeric and dry-mesic) at the start of the growing season. Temperature sums were calculated in degree-days (DD) ≥5 °C from 1 January and 20 March, i.e., spring equinox, to account for photoperiodic control of release from winter dormancy. Threshold temperatures at which xylogenesis had a 0.5 probability of being active were calculated by logistic regression. Onset of xylem growth, which was not significantly different between the xeric and dry-mesic sites, ranged from mid-April in 2007 to early May in 2008. Among most study years, statistically significant differences (Pdrought stress forces P. sylvestris to draw upon water reserves in the stem for enlargement of first tracheids after cambial resumption in spring. © The Author 2011. Published by Oxford University Press. All rights reserved.

  8. Morphometric Relationship, Growth, and Condition Factor of Flyingfish, Hirundicththys oxycephalus during spawning season

    Science.gov (United States)

    Tuapetel, Friesland; Nessa, Natsir; Alam Ali, Syamsu; Sudirman; Hutubessy, B. G.; Mosse, J. W.

    2017-10-01

    Flyingfish, Hirundichthys oxycephalus together with its congener species has become a major artisanal fishery resource from the Seram Sea, an area between Seram and Papua Island. However, biological information about this species has been poorly documented. Our current study focused on the growth and morphometric relationships of spawning cohorts during spawning season (June to October 2013). Flyingfish which were trapped in bale-bale, an egg aggregation device for flying fish, were collected offshore of the Southeastern Seram Sea. Total samples of 1693 with Fork Length (FL) ranged from 156.15mm to 245.52mm and total weight from 53.15gr to 115.45gr. Von Bertalanffy growth functions (L∞) for-pooled sexes were FL = 251mm [1-e (1.82 (t+0.060)], K=1.82 and t0 = 0.060. Morphometrically, significant differences were observed for all individuals between sexes (F=14.20, P=0.0002), sampling locations (F=88.48 Pfish generally declined in July-August. During spawning season, this fish tended to form single spawning cohort. The results of this study provide a significant understanding of the life history of this valuable fish inhabiting this particular region that rarely receives scientific investigation. For management purposes, harvesting eggs including broodstocks will lead to critical population depletion.

  9. Stable isotope ratios of marijuana. I. Carbon and nitrogen stable isotopes describe growth conditions.

    Science.gov (United States)

    West, Jason B; Hurley, Janet M; Ehleringer, James R

    2009-01-01

    There remains significant uncertainty in illicit marijuana cultivation. We analyzed the delta(13)C and delta(15)N of 508 domestic samples from known U.S.A. counties, 31 seized from a single location, 5 samples grown in Mexico and Colombia, and 10 northwest border seizures. For a subset, inflorescences and leaves were analyzed separately. These data revealed a strong correspondence, with inflorescences having slightly higher delta(13)C and delta(15)N values than leaves. A framework for interpreting these results is introduced and evaluated. Samples identified as outdoor-grown by delta(13)C were generally recorded as such by the Drug Enforcement Administration (DEA). DEA-classified indoor-grown samples had the most negative delta(13)C values, consistent with indoor cultivation, although many were also in the outdoor-grown domain. Delta(15)N indicated a wide range of fertilizers across the dataset. Samples seized at the single location suggested multiple sources. Northwest border delta(13)C values suggested indoor growth, whereas for the Mexican and Colombian samples they indicated outdoor growth.

  10. Profiling of lipid and glycogen accumulations under different growth conditions in the sulfothermophilic red alga Galdieria sulphuraria.

    Science.gov (United States)

    Sakurai, Toshihiro; Aoki, Motohide; Ju, Xiaohui; Ueda, Tatsuya; Nakamura, Yasunori; Fujiwara, Shoko; Umemura, Tomonari; Tsuzuki, Mikio; Minoda, Ayumi

    2016-01-01

    The unicellular red alga Galdieria sulphuraria grows efficiently and produces a large amount of biomass in acidic conditions at high temperatures. It has great potential to produce biofuels and other beneficial compounds without becoming contaminated with other organisms. In G. sulphuraria, biomass measurements and glycogen and lipid analyses demonstrated that the amounts and compositions of glycogen and lipids differed when cells were grown under autotrophic, mixotrophic, and heterotrophic conditions. Maximum biomass production was obtained in the mixotrophic culture. High amounts of glycogen were obtained in the mixotrophic cultures, while the amounts of neutral lipids were similar between mixotrophic and heterotrophic cultures. The amounts of neutral lipids were highest in red algae, including thermophiles. Glycogen structure and fatty acids compositions largely depended on the growth conditions. Copyright © 2015. Published by Elsevier Ltd.

  11. Effect of NiO growth conditions on the bipolar resistance memory switching of Pt/NiO/SRO structure

    International Nuclear Information System (INIS)

    Kurnia, F.; Hadiyawarman, H.; Jung, C. U.; Liu, C. L.; Lee, S. B.; Yang, S. M.; Park, H. W.; Song, S. J.; Hwang, C. S.

    2010-01-01

    We deposited NiO thin films with SrRuO 3 bottom electrodes on SrTiO 3 (001) substrates by using pulsed laser deposition. The growth temperature and the oxygen pressure were varied in order to obtain NiO films with different structural and electrical properties. We investigated the I-V characteristics of the Pt/NiO/SRO structures and observed a strong dependence of bipolar resistance switching on the growth conditions of the NiO thin films. Stable bipolar memory resistance switching was observed only in the devices with NiO films deposited at 400 .deg. C and 10 mTorr of O 2 . The off-state I-V curve of bipolar switching showed a linear fitting to the Schottky effect, indicating its origin in the NiO/SRO interface. Our results suggest that the growth conditions of NiO may affect the bipolar switching behavior through the film's resistance, the film's crystallinity, or the status of the grain boundaries.

  12. [Effect of exogenous sucrose on growth and active ingredient content of licorice seedlings under salt stress conditions].

    Science.gov (United States)

    Liu, Fu-zhi; Yang, Jun

    2015-11-01

    Licorice seedlings were taken as experimental materials, an experiment was conducted to study the effects of exogenous sucrose on growth and active ingredient content of licorice seedlings under NaCl stress conditions. The results of this study showed that under salt stress conditions, after adding a certain concentration of exogenous sucrose, the licorice seedlings day of relative growth rate was increasing, and this stress can be a significant weakening effect, indicating that exogenous sucrose salt stress-relieving effect. The total flavonoids and phenylalanine ammonia lyase (PAL) activity were significantly increased, the exogenous sucrose can mitigated the seedling roots under salt stress, the licorice flavonoid content in the enhanced growth was largely due to the activity of PAL an increased, when the concentration of exogenous sucrose wae 10 mmol x L(-1), PAL activity reaching a maximum, when the concentration of exogenous sucrose was 15 mmol x L(-1), PAL activity turned into a downward trend, the results indicating that this mitigation has concentration effect. After applying different concentrations of exogenous sugar, the contents of liquiritin changes with the change of flavonoids content was similar. After applying different concentrations of exogenous sucrose, the content of licorice acid under salt stress was higher than the levels were not reached during salt stress, the impact of exogenous sucrose concentration gradient of licorice acid accumulation was not obvious.

  13. Effects of acidifying ocean conditions on growth and survival of two life stages of the blue crab, Callinectes sapidus.

    Science.gov (United States)

    Giltz, S.; Taylor, C.

    2016-02-01

    Blue crabs, Callinectes sapidus, begin their larval phase offshore and circulate for approximately 30 days before settling near shore. As crabs transition to the juvenile stage, they move into coastal or estuarine environments characterized by lower salinity. Presently the average pH of the ocean is 8.1, 30% down from the beginning of the industrial revolution and is forecasted to drop to 7.8 by 2100. Decreasing pH causes dissolution of calcium carbonate shells, but the overall effects on crustaceans, such as blue crabs, are unknown. This study investigated the effect of a lower pH environment on the growth, survival, carapace hardness and molt frequency of larval and juvenile blue crabs in the Northern Gulf of Mexico. Larval crabs showed delayed growth under low pH (7.8) conditions compared to crabs in a control (present day) pH (8.1) environment. Population crashes (complete mortality) were experienced in 55% of the low pH aquaria but not in any of the control aquaria, suggesting that acidification poses a mortality risk. Under low pH conditions the intermolt duration decreased in juveniles, but the body length and weight did not differ from crabs raised in the control pH. Larvae (in tanks that did not crash) and juveniles did not experience increased mortality from a lower pH, but there do appear to be sublethal effects on growth and molting that differ between life history stages.

  14. Growth and essential oil production by Martianthus leucocephalus grown under the edaphoclimatic conditions of Feira de Santana, Bahia, Brazil

    Directory of Open Access Journals (Sweden)

    Bianca Oliveira de Azevedo

    2015-01-01

    Full Text Available ABSTRACT: The semiarid region of Brazil holds a great richness of medicinal and aromatic plants with considerable potential for pharmaceutical, food, cosmetic and biopesticide industries. Martianthus leucocephalus (Mart. Ex Benth. J. F. B. Pastore is endemic to this region, and its essential oils contain a principle compound, isobornyl formate, which demonstrates antimicrobial activity against Bacilus cereus, Staphylococcus aureus and Candida albicans. In spite of its significant pharmacological potential, little is known about its growth. In light of the influence of seasonality on plant growth, development, and secondary metabolism, the present study evaluated the growth and essential oil content of M. leucocephalus grown and harvested during different months of the year in the edaphoclimatic conditions of Feira de Santana, Bahia State, Brazil. The experimental design was entirely randomized, with twelve harvesting periods and five replicates. The study acquired monthly data of mean temperatures, relative humidity, rainfall, irradiance, and photoperiod from the National Institute of Meteorology (INMET and quantified the fresh and dry weights of leaves, flowers and branches, as well as leaf area, and essential oil content. The data were submitted to Spearman correlation analysis and the means were compared using the Scott-Knott test. Total leaf masses and oil contents were higher during periods with longer photoperiods and higher solar irradiance. Rainfall and relative humidity reduced plant growth and essential oil content. Higher total mean dry masses were recorded from September to January (except October, while oil content was higher in March.

  15. Unearthing Bacillus endophytes from desert plants that enhance growth of Arabidopsis thaliana under abiotic stress conditions

    KAUST Repository

    Bokhari, Ameerah

    2018-01-01

    that these bacteria can confer resilience to plants under salt stress conditions. B. circulans (PK3-15 and PK3-109), B. cereus (PK6-15) B. subtilis (PK3-9) and B. licheniformis (PK5-26) displayed the ability to increased the fresh weight of A. thaliana under salt

  16. Poverty and inequality in Latin America: From growth to conditional transfers of income

    Directory of Open Access Journals (Sweden)

    José Ignacio Antón Pérez

    2009-05-01

    Full Text Available This article focuses on the scale, interpretation and policies of the fight against inequality and poverty in Latin America. To this end, the article presents, firstly, the continent’s situation with respect to inequality and poverty, as well as its evolution over the past decades. Secondly, the authors examine the changing interpretation that has been made – through the economy and economic policy – of the importance of inequality and poverty in development processes. The article then offers a review of this debate, providing information on the link between economic growth and poverty in Latin America, given the fact that independently of this link, many policies exist aimed at combating poverty, whether to reduce its intensity or its effects. Finally, and prior to the conclusions, the authors present an overview of this kind of policies in Latin America, focusing particularly on the ones that have proven most effective.

  17. Growth of GaMnAs under near-stoichiometric conditions

    International Nuclear Information System (INIS)

    Avrutin, V.; Humienik, D.; Frank, S.; Koeder, A.; Schoch, W.; Limmer, W.; Sauer, R.; Waag, A.

    2005-01-01

    We studied the effect of the V/III flux ratio and substrate temperature on magnetotransport properties and lattice parameters of Ga 0.96 Mn 0.04 As grown by molecular-beam epitaxy. For all the substrate temperatures, the conductivities and Curie temperatures of the layers were found to increase as the V/III flux ratio approaches 1. A Curie temperature as high as 95 K was achieved for the Ga 0.96 Mn 0.04 As samples grown at 240 deg. C and a V/III ratio of about 1.5. The lattice parameter of Ga 0.96 Mn 0.04 As increased with decreasing V/III ratio and/or increasing growth temperature. Possible reasons for the effect of the V/III ratio on the magnetotransport properties and lattice parameter of GaMnAs are discussed

  18. Energy Taxis Drives Campylobacter jejuni toward the Most Favorable Conditions for Growth

    DEFF Research Database (Denmark)

    Vegge, C.S.; Brondsted, L.; Li, Yiping

    2009-01-01

    Campylobacter jejuni is a serious food-borne bacterial pathogen in the developed world. Poultry is a major reservoir, and C. jejuni appears highly adapted to the gastrointestinal tract of birds. Several factors are important for chicken colonization and virulence, including a taxis mechanism...... identified as new attractants of C. jejuni, and we observed that chemical substances promoting tactic attraction are all known to support the growth of this organism. The attractants could be categorized as carbon sources and electron donors and acceptors, and we furthermore observed a correlation between...... an attractant's potency and its efficiency as an energy source. The tactic attraction was inhibited by the respiratory inhibitors HQNO (2-n-heptyl-4-hydroxyquinoline N-oxide) and sodium azide, which significantly reduce energy production by oxidative phosphorylation. These findings strongly indicate that energy...

  19. On the conditions for nonlinear growth in magnetospheric chorus and triggered emissions

    Science.gov (United States)

    Gołkowski, Mark; Gibby, Andrew R.

    2017-09-01

    The nonlinear whistler mode instability associated with magnetospheric chorus and VLF triggered emissions continues to be poorly understood. Following up on formulations of other authors, an analytical exploration of the stability of the phenomenon from a new vantage point is given. This exploration derives an additional requirement on the anisotropy of the energetic electron distribution relative to the linear treatment of the instability, and shows that the nonlinear instability is most favorable to increasing growth rate when electrons become initially trapped in the wave potential of a constant frequency wave. These results imply that the initiation of the nonlinear instability at the equator requires a positive frequency sweep rate, while the initiation of the instability by a constant frequency triggering wave must occur at a location downstream of the geomagnetic equator.

  20. Assessing the Effect of Planting Date on Safflower Cultivars Growth and Seed Yield in Rafsanjan Condition

    Directory of Open Access Journals (Sweden)

    F Khatib

    2015-09-01

    Full Text Available The use of appropriate cultivar and planting date is the most important principles of agronomy; therefore, the aim of the present study was to consider the growth indices of different safflower cultivars and their relationships with seed yield. For this purpose, an experiment was conducted as factorial in randomized block design with four replicates included three planting dates (4 April, 25 April and 16 May and four safflower cultivars (411, Sina, Local Esfahan and Sofeh. The maximum leaf area index (2.33 obtained in the first planting date that it was not significantly different with the second planting date but it decreased up to 70% in the third planting date. In the first planting date, the maximum LAI obtained for Local Esfahan and 411 cultivars. Maximum total dry matter was 124.2 g m-2 for the first planting date that it decreased up to 31 and 78% in the second and third planting dates, respectively. In this planting date Sina and Local Esfahan cultivars had the higher dry matter. Maximum crop growth rate for the first planting date was 38.84 g m-2d-1 that it decreased up to 41 and 66% in the second and third planting dates, respectively. In this planting date, the highest total dry matter obtained for the Local Esfahan cultivar. The results showed that the maximum value of seed yield dedicated to 411 and Local Esfahan cultivars that it had the high correlation with maximum total dry matter. In respect to the present study, it is suggested to use 411 or Local Esfahan cultivars in the first planting date.

  1. Prevention of melanin formation during aryl alcohol oxidase production under growth-limited conditions using an Aspergillus nidulans cell factory.

    Science.gov (United States)

    Pardo-Planas, Oscar; Prade, Rolf A; Müller, Michael; Atiyeh, Hasan K; Wilkins, Mark R

    2017-11-01

    An Aspergillus nidulans cell factory was genetically engineered to produce an aryl alcohol oxidase (AAO). The cell factory initiated production of melanin when growth-limited conditions were established using stationary plates and shaken flasks. This phenomenon was more pronounced when the strain was cultured in a trickle bed reactor (TBR). This study investigated different approaches to reduce melanin formation in fungal mycelia and liquid medium in order to increase the enzyme production yield. Removal of copper from the medium recipe reduced melanin formation in agar cultures and increased enzyme activities by 48% in agitated liquid cultures. Copper has been reported as a key element for tyrosinase, an enzyme responsible for melanin production. Ascorbic acid (0.44g/L) stopped melanin accumulation, did not affect growth parameters and resulted in AAO activity that was more than two-fold greater than a control treatment with no ascorbic acid. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. In-situ transmission electron microscopy growth of nanoparticles under extreme conditions

    International Nuclear Information System (INIS)

    Luce, F. P.; Azevedo, G. de M.; Baptista, D. L.; Zawislak, F. C.; Oliviero, E.; Fichtner, P. F. P.

    2016-01-01

    The formation and time resolved behavior of individual Pb nanoparticles embedded in silica have been studied by in-situ transmission electron microscopy observations at high temperatures (400–1100 °C) and under 200 keV electron irradiation. It is shown that under such extreme conditions, nanoparticles can migrate at long distances presenting a Brownian-like behavior and eventually coalesce. The particle migration phenomenon is discussed considering the influence of the thermal energy and the electron irradiation effects on the atomic diffusion process which is shown to control particle migration. These results and comparison with ex-situ experiments tackle the stability and the microstructure evolution of nanoparticles systems under extreme conditions. It elucidates on the effects of energetic particle irradiation-annealing treatments either as a tool or as a detrimental issue that could hamper their long-term applications in radiation-harsh environments such as in space or nuclear sectors

  3. Linking atmospheric synoptic transport, cloud phase, surface energy fluxes, and sea-ice growth: observations of midwinter SHEBA conditions

    Science.gov (United States)

    Persson, P. Ola G.; Shupe, Matthew D.; Perovich, Don; Solomon, Amy

    2017-08-01

    Observations from the Surface Heat Budget of the Arctic Ocean (SHEBA) project are used to describe a sequence of events linking midwinter long-range advection of atmospheric heat and moisture into the Arctic Basin, formation of supercooled liquid water clouds, enhancement of net surface energy fluxes through increased downwelling longwave radiation, and reduction in near-surface conductive heat flux loss due to a warming of the surface, thereby leading to a reduction in sea-ice bottom growth. The analyses provide details of two events during Jan. 1-12, 1998, one entering the Arctic through Fram Strait and the other from northeast Siberia; winter statistics extend the results. Both deep, precipitating frontal clouds and post-frontal stratocumulus clouds impact the surface radiation and energy budget. Cloud liquid water, occurring preferentially in stratocumulus clouds extending into the base of the inversion, provides the strongest impact on surface radiation and hence modulates the surface forcing, as found previously. The observations suggest a minimum water vapor threshold, likely case dependent, for producing liquid water clouds. Through responses to the radiative forcing and surface warming, this cloud liquid water also modulates the turbulent and conductive heat fluxes, and produces a thermal wave penetrating into the sea ice. About 20-33 % of the observed variations of bottom ice growth can be directly linked to variations in surface conductive heat flux, with retarded ice growth occurring several days after these moisture plumes reduce the surface conductive heat flux. This sequence of events modulate pack-ice wintertime environmental conditions and total ice growth, and has implications for the annual sea-ice evolution, especially for the current conditions of extensive thinner ice.

  4. Characterization of Transient Plasma Ignition Flame Kernel Growth for Varying Inlet Conditions

    Science.gov (United States)

    2009-12-01

    from Intercity Manufacturing. Without their expertise in precision machining this thesis would not have been possible. Their countless hours spent...somewhere within the combustor due to the time required to produce the required conditions, and will be travelling at near Mach 5 speeds for most...atmospheric pressure. This sudden drop in pressure creates a rarefaction wave that travels forward in the combustor. The blowdown time for a 1 meter long

  5. Cadmium removal by Euglena gracilis is enhanced under anaerobic growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Santiago-Martínez, M. Geovanni; Lira-Silva, Elizabeth; Encalada, Rusely; Pineda, Erika; Gallardo-Pérez, Juan Carlos [Departamento de Bioquímica, Instituto Nacional de Cardiología (Mexico); Zepeda-Rodriguez, Armando [Facultad de Medicina, UNAM, Mexico City (Mexico); Moreno-Sánchez, Rafael; Saavedra, Emma [Departamento de Bioquímica, Instituto Nacional de Cardiología (Mexico); Jasso-Chávez, Ricardo, E-mail: rjass_cardiol@yahoo.com.mx [Departamento de Bioquímica, Instituto Nacional de Cardiología (Mexico)

    2015-05-15

    Highlights: • The protist Euglena gracilis had the ability to grow and remove large amounts of Cd{sup 2+} under anaerobic conditions. • High biomass was attained by combination of glycolytic and mitochondrial carbon sources. • Routes of degradation of glucose, glutamate and malate under anaerobic conditions in E. gracilis are described. • Biosorption was the main mechanism of Cd{sup 2+} removal in anaerobiosis, whereas the Cd{sup 2+} intracellularly accumulated was inactivated by thiol-molecules and polyphosphate. - Abstract: The facultative protist Euglena gracilis, a heavy metal hyper-accumulator, was grown under photo-heterotrophic and extreme conditions (acidic pH, anaerobiosis and with Cd{sup 2+}) and biochemically characterized. High biomass (8.5 × 10{sup 6} cells mL{sup −1}) was reached after 10 days of culture. Under anaerobiosis, photosynthetic activity built up a microaerophilic environment of 0.7% O{sub 2}, which was sufficient to allow mitochondrial respiratory activity: glutamate and malate were fully consumed, whereas 25–33% of the added glucose was consumed. In anaerobic cells, photosynthesis but not respiration was activated by Cd{sup 2+} which induced higher oxidative stress. Malondialdehyde (MDA) levels were 20 times lower in control cells under anaerobiosis than in aerobiosis, although Cd{sup 2+} induced a higher MDA production. Cd{sup 2+} stress induced increased contents of chelating thiols (cysteine, glutathione and phytochelatins) and polyphosphate. Biosorption (90%) and intracellular accumulation (30%) were the mechanisms by which anaerobic cells removed Cd{sup 2+} from medium, which was 36% higher versus aerobic cells. The present study indicated that E. gracilis has the ability to remove Cd{sup 2+} under anaerobic conditions, which might be advantageous for metal removal in sediments from polluted water bodies or bioreactors, where the O{sub 2} concentration is particularly low.

  6. Cadmium removal by Euglena gracilis is enhanced under anaerobic growth conditions

    International Nuclear Information System (INIS)

    Santiago-Martínez, M. Geovanni; Lira-Silva, Elizabeth; Encalada, Rusely; Pineda, Erika; Gallardo-Pérez, Juan Carlos; Zepeda-Rodriguez, Armando; Moreno-Sánchez, Rafael; Saavedra, Emma; Jasso-Chávez, Ricardo

    2015-01-01

    Highlights: • The protist Euglena gracilis had the ability to grow and remove large amounts of Cd 2+ under anaerobic conditions. • High biomass was attained by combination of glycolytic and mitochondrial carbon sources. • Routes of degradation of glucose, glutamate and malate under anaerobic conditions in E. gracilis are described. • Biosorption was the main mechanism of Cd 2+ removal in anaerobiosis, whereas the Cd 2+ intracellularly accumulated was inactivated by thiol-molecules and polyphosphate. - Abstract: The facultative protist Euglena gracilis, a heavy metal hyper-accumulator, was grown under photo-heterotrophic and extreme conditions (acidic pH, anaerobiosis and with Cd 2+ ) and biochemically characterized. High biomass (8.5 × 10 6 cells mL −1 ) was reached after 10 days of culture. Under anaerobiosis, photosynthetic activity built up a microaerophilic environment of 0.7% O 2 , which was sufficient to allow mitochondrial respiratory activity: glutamate and malate were fully consumed, whereas 25–33% of the added glucose was consumed. In anaerobic cells, photosynthesis but not respiration was activated by Cd 2+ which induced higher oxidative stress. Malondialdehyde (MDA) levels were 20 times lower in control cells under anaerobiosis than in aerobiosis, although Cd 2+ induced a higher MDA production. Cd 2+ stress induced increased contents of chelating thiols (cysteine, glutathione and phytochelatins) and polyphosphate. Biosorption (90%) and intracellular accumulation (30%) were the mechanisms by which anaerobic cells removed Cd 2+ from medium, which was 36% higher versus aerobic cells. The present study indicated that E. gracilis has the ability to remove Cd 2+ under anaerobic conditions, which might be advantageous for metal removal in sediments from polluted water bodies or bioreactors, where the O 2 concentration is particularly low

  7. Bacterial epimerization as a route for deoxynivalenol detoxification: the influence of growth and environmental conditions.

    Directory of Open Access Journals (Sweden)

    Jian Wei eHe

    2016-04-01

    Full Text Available Deoxynivalenol (DON is a toxic secondary metabolite produced by several Fusarium species that infest wheat and corn. Food and feed contaminated with DON pose a health risk to both humans and livestock and form a major barrier for international trade. Microbial detoxification represents an alternative approach to the physical and chemical detoxification methods of DON-contaminated grains. The present study details the characterization of a novel bacterium, Devosia mutans 17-2-E-8, that is capable of transforming DON to a non-toxic stereoisomer, 3-epi-deoxynivalenol under aerobic conditions, mild temperature (25-30 oC, and neutral pH. The biotransformation takes place in the presence of rich sources of organic nitrogen and carbon without the need of DON to be the sole carbon source. The process is enzymatic in nature and endures a high detoxification capacity (3 µg DON/h/108 cells. The above conditions collectively suggest the possibility of utilizing the isolated bacterium as a feed treatment to address DON contamination under empirical field conditions.

  8. High throughput nanostructure-initiator mass spectrometry screening of microbial growth conditions for maximal β-glucosidase production.

    Science.gov (United States)

    Cheng, Xiaoliang; Hiras, Jennifer; Deng, Kai; Bowen, Benjamin; Simmons, Blake A; Adams, Paul D; Singer, Steven W; Northen, Trent R

    2013-01-01

    Production of biofuels via enzymatic hydrolysis of complex plant polysaccharides is a subject of intense global interest. Microbial communities are known to express a wide range of enzymes necessary for the saccharification of lignocellulosic feedstocks and serve as a powerful reservoir for enzyme discovery. However, the growth temperature and conditions that yield high cellulase activity vary widely, and the throughput to identify optimal conditions has been limited by the slow handling and conventional analysis. A rapid method that uses small volumes of isolate culture to resolve specific enzyme activity is needed. In this work, a high throughput nanostructure-initiator mass spectrometry (NIMS)-based approach was developed for screening a thermophilic cellulolytic actinomycete, Thermobispora bispora, for β-glucosidase production under various growth conditions. Media that produced high β-glucosidase activity were found to be I/S + glucose or microcrystalline cellulose (MCC), Medium 84 + rolled oats, and M9TE + MCC at 45°C. Supernatants of cell cultures grown in M9TE + 1% MCC cleaved 2.5 times more substrate at 45°C than at all other temperatures. While T. bispora is reported to grow optimally at 60°C in Medium 84 + rolled oats and M9TE + 1% MCC, approximately 40% more conversion was observed at 45°C. This high throughput NIMS approach may provide an important tool in discovery and characterization of enzymes from environmental microbes for industrial and biofuel applications.

  9. Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, Kathleen M. [State Univ. of New York (SUNY),Buffalo, NY (United States)

    1990-12-01

    The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26°C and downshifted 30-26-30°C) and females (constant 30°C and upshifted 26-30-26°C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26°C group and 93% males from the downshifted group. 100% females resulted from both the constant 30°C group and the upshifted group. Turtles hatching from eggs incubated constantly at 26°C were significantly larger than hatchlings from eggs incubated at a constant 30°C or downshifted. Hatchlings were raised in individual aquaria at 25°C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30°C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.

  10. Effects of egg incubation condition on the post-hatching growth and performance of the snapping turtle, Chelydra serpentina

    Energy Technology Data Exchange (ETDEWEB)

    Ryan, K.M.

    1990-12-01

    The effect of incubation temperature on the post-hatching growth and performance capacities of the common snapping turtle, Chelydra serpentina was investigated in the laboratory. Turtle eggs were collected from four sites in New York State and randomly assigned to four incubation temperature treatments to produce males (constant 26[degree]C and downshifted 30-26-30[degree]C) and females (constant 30[degree]C and upshifted 26-30-26[degree]C) under constant and altered temperature regimes. The incubation conditions resulted in 92% males from the constant 26[degree]C group and 93% males from the downshifted group. 100% females resulted from both the constant 30[degree]C group and the upshifted group. Turtles hatching from eggs incubated constantly at 26[degree]C were significantly larger than hatchlings from eggs incubated at a constant 30[degree]C or downshifted. Hatchlings were raised in individual aquaria at 25[degree]C and fed earthworms and fish. After a 9-month growth period, turtles which had been incubated at a constant 30[degree]C gained significantly more mass than did turtles from eggs which had been downshifted or upshifted. There was no extended effect of incubation condition on Post-hatching performance and learning ability as measured by righting and feeding responses. Thus, the mass gain differences seen in this study suggest that physiological differences do result as the consequence of incubation condition. However, these physiological differences are not reflected in normal locomotive or feeding behavior.

  11. Effect of iron dextran injection on growth performance of crossbred and desi piglets under farm and village conditions

    Directory of Open Access Journals (Sweden)

    Raghuvir Ranjan

    Full Text Available Aim: To study the effect of iron dextran injection on growth performance of crossbred and desi piglets under farm and village conditions. Materials and Methods: The experiments were conducted in Pig Breeding Farm, Ranchi Veterinary College, Ranchi and different villages on crossbred and desi preweaned piglets. The piglets were divided into three treatment groups as T 1 (control, T2 (injected iron dextran @ 1 ml (50mg I/M twice at 3rd and 14th days of age and T3 (injected iron dextran @ 2 ml 2 3 (100mg I/M once at 3rd day of age. Results: The average body weight of crossbred piglets in farm condition of T1 , T2 and T3 groups at weaning (8 week were 7.162±0.365, 9.985±0.281 and 9.572±0.295 kg, respectively. The piglets of T2 group showed better performance over T3 and T1 groups in farm and village conditions on crossbred and desi piglets. Conclusion: On the basis of present findings it may be concluded that irondextran (50mg/ ml injection should be given to all piglets @ 1 ml I/M during preweaning period at 3rd and 14th day of age for better growth of piglets. [Vet World 2012; 5(10.000: 599-602

  12. Enhancing proliferation and optimizing the culture condition for human bone marrow stromal cells using hypoxia and fibroblast growth factor-2

    Directory of Open Access Journals (Sweden)

    Jung-Seok Lee

    2018-04-01

    Full Text Available This study aimed to determine the cellular characteristics and behaviors of human bone marrow stromal cells (hBMSCs expanded in media in a hypoxic or normoxic condition and with or without fibroblast growth factor-2 (FGF-2 treatment. hBMSCs isolated from the vertebral body and expanded in these four groups were evaluated for cellular proliferation/migration, colony-forming units, cell-surface characterization, in vitro differentiation, in vivo transplantation, and gene expression. Culturing hBMSCs using a particular environmental factor (hypoxia and with the addition of FGF-2 increased the cellular proliferation rate while enhancing the regenerative potential, modulated the multipotency-related processes (enhanced chondrogenesis-related processes/osteogenesis, but reduced adipogenesis, and increased cellular migration and collagen formation. The gene expression levels in the experimental samples showed activation of the hypoxia-inducible factor-1 pathway and glycolysis in the hypoxic condition, with this not being affected by the addition of FGF-2. The concurrent application of hypoxia and FGF-2 could provide a favorable condition for culturing hBMSCs to be used in clinical applications associated with bone tissue engineering, due to the enhancement of cellular proliferation and regenerative potential. Keywords: Bone marrow stromal cells, Hypoxia, Fibroblast growth factor, Tissue regeneration, Microenvironment interactions

  13. Temperature and water stress during conditioning and incubation phase affecting Orobanche crenata seed germination and radicle growth

    Directory of Open Access Journals (Sweden)

    JUAN eMORAL

    2015-06-01

    Full Text Available Orobanche crenata is a holoparasitic plant that is potentially devastating to crop yield of legume species. Soil temperature and humidity are known to affect seed germination, however, the extent of their influence on germination and radicle growth of those of O. crenata is largely unknown. In this work, we studied the effects of temperature, water potential (Ψt and the type of water stress (matric or osmotic on O. crenata seeds during conditioning and incubation periods. We found that seeds germinated between 5 and 30ºC during both periods, with a maximum around 20ºC. Germination increased with increasing Ψt from -1.2 to 0 MPa during conditioning and incubation periods. Likewise, seed germination increased logarithmically with length of conditioning period until 40 days. The impact of the type of water stress on seed germination was similar, although the radicle growth of seeds under osmotic stress was lower than under matric stress, what could explain the lowest infestation of Orobanche spp. in regions characterized by saline soil. The data in this study will be useful to forecast infection of host roots by O. crenata.

  14. Temperature and water stress during conditioning and incubation phase affecting Orobanche crenata seed germination and radicle growth.

    Science.gov (United States)

    Moral, Juan; Lozano-Baena, María Dolores; Rubiales, Diego

    2015-01-01

    Orobanche crenata is a holoparasitic plant that is potentially devastating to crop yield of legume species. Soil temperature and humidity are known to affect seed germination, however, the extent of their influence on germination and radicle growth of those of O. crenata is largely unknown. In this work, we studied the effects of temperature, water potential (Ψt) and the type of water stress (matric or osmotic) on O. crenata seeds during conditioning and incubation periods. We found that seeds germinated between 5 and 30°C during both periods, with a maximum around 20°C. Germination increased with increasing Ψt from -1.2 to 0 MPa during conditioning and incubation periods. Likewise, seed germination increased logarithmically with length of conditioning period until 40 days. The impact of the type of water stress on seed germination was similar, although the radicle growth of seeds under osmotic stress was lower than under matric stress, what could explain the lowest infestation of Orobanche sp. in regions characterized by saline soil. The data in this study will be useful to forecast infection of host roots by O. crenata.

  15. High throughput nanostructure-initiator mass spectrometry screening of microbial growth conditions for maximal β-glucosidase production

    Directory of Open Access Journals (Sweden)

    Xiaoliang eCheng

    2013-12-01

    Full Text Available Production of biofuels via enzymatic hydrolysis of complex plant polysaccharides is a subject of intense global interest. Microbial communities are known to express a wide range of enzymes necessary for the saccharification of lignocellulosic feedstocks and serve as a powerful reservoir for enzyme discovery. However, the growth temperature and conditions that yield high cellulase activity vary widely, and the throughput to identify optimal conditions has been limited by the slow handling and conventional analysis. A rapid method that uses small volumes of isolate culture to resolve specific enzyme activity is needed. In this work, a high throughput nanostructure-initiator mass spectrometry (NIMS based approach was developed for screening a thermophilic cellulolytic actinomycete, Thermobispora bispora, for β-glucosidase production under various growth conditions. Media that produced high β-glucosidase activity were found to be I/S + glucose or microcrystalline cellulose (MCC, Medium 84 + rolled oats, and M9TE + MCC at 45 °C. Supernatants of cell cultures grown in M9TE + 1% MCC cleaved 2.5 times more substrate at 45 °C than at all other temperatures. While T. bispora is reported to grow optimally at 60 °C in Medium 84 + rolled oats and M9TE + 1% MCC, approximately 40% more conversion was observed at 45 °C. This high throughput NIMS approach may provide an important tool in discovery and characterization of enzymes from environmental microbes for industrial and biofuel applications.

  16. An investigation into the stability of commercial versus MG63-derived hepatocyte growth factor under flow cultivation conditions.

    Science.gov (United States)

    Meneghello, Giulia; Storm, Michael P; Chaudhuri, Julian B; De Bank, Paul A; Ellis, Marianne J

    2015-03-01

    The scale-up of tissue engineering cell culture must ensure that conditions are maintained while also being cost effective. Here we analyse the stability of hepatocyte growth factor (HGF) to investigate whether concentrations change under dynamic conditions, and compare commercial recombinant human HGF as an additive in 'standard medium', to HGF secreted by the osteosarcoma cell line MG63 as a 'preconditioned medium'. After 3 h under flow conditions, HGF in the standard medium degraded to 40% of its original concentration but HGF in the preconditioned medium remained at 100%. The concentration of secreted HGF was 10 times greater than the working concentration of commercially-available HGF. Thus HGF within this medium has increased stability; MG63-derived HGF should therefore be investigated as a cost-effective alternative to current lyophilised powders for use in in vitro models. Furthermore, we recommend that those intending to use HGF (or other growth factors) should consider similar stability testing before embarking on experiments with media flow.

  17. Variations in water status, gas exchange, and growth in Rosmarinus officinalis plants infected with Glomus deserticola under drought conditions.

    Science.gov (United States)

    Sánchez-Blanco, Ma Jesús; Ferrández, Trinitario; Morales, Ma Angeles; Morte, Asunción; Alarcón, Juan José

    2004-06-01

    The influence of the arbuscular mycorrhizal fungus Glomus deserticola on the water relations, gas exchange parameters, and vegetative growth of Rosmarinus officinalis plants under water stress was studied. Plants were grown with and without the mycorrhizal fungus under glasshouse conditions and subjected to water stress by withholding irrigation water for 14 days. Along the experimental period, a significant effect of the fungus on the plant growth was observed, and under water stress, mycorrhizal plants showed an increase in aerial and root biomass compared to non-mycorrhizal plants. The decrease in the soil water potential generated a decrease in leaf water potential (psi(l)) and stem water potential (psi(x)) of mycorrhizal and non-mycorrhizal plants, with this decrease being lower in mycorrhizal water-stressed plants. Mycorrhization also had positive effects on the root hydraulic conductivity (Lp) of water stressed plants. Furthermore, mycorrhizal-stressed plants showed a more important decrease in osmotic potential at full turgor (psi(os)) than did non-mycorrhizal-stressed plants, indicating the capacity of osmotic adjustment. Mycorrhizal infection also improved photosynthetic activity (Pn) and stomatal conductance (g(s)) in plants under water stress compared to the non-mycorrhizal-stressed plants. A similar behaviour was observed in the photochemical efficiency of PSII (Fv/Fm) with this parameter being lower in non-mycorrhizal plants than in mycorrhizal plants under water stress conditions. In the same way, under water restriction, mycorrhizal plants showed higher values of chlorophyll content than did non-mycorrhizal plants. Thus, the results obtained indicated that the mycorrhizal symbiosis had a beneficial effect on the water status and growth of Rosmarinus officinalis plants under water-stress conditions.

  18. Generic conditions for suppressing the coherent synchrotron radiation induced emittance growth in a two-dipole achromat

    Science.gov (United States)

    Jiao, Yi; Cui, Xiaohao; Huang, Xiyang; Xu, Gang

    2014-06-01

    The effect of the coherent synchrotron radiation (CSR) becomes evident, and leads to increased beam energy spread and transverse emittance dilution, as both the emittance and bunch length of the electron beams are continuously pushed down in present and forthcoming high-brightness light sources and linear colliders. Suppressing this effect is important to preserve the expected machine performance. Methods of the R-matrix analysis and the Courant-Snyder formalism analysis have been proposed to evaluate and to suppress the emittance growth due to CSR in achromatic cells. In this paper a few important modifications are made on these two methods, which enable us to prove that these two methods are equivalent to each other. With the modified analysis, we obtain explicit and generic conditions of cancelling the CSR-driven emittance excitation in a single achromat consisting of two dipoles of arbitrary bending angles. In spite of the fact that the analysis constrains itself in a linear regime, based on the assumption that CSR-induced particle energy deviation is proportional to both θ and ρ1/3, with θ being the bending angle and ρ the bending radius, it is demonstrated through ELEGANT simulations that the conditions derived from this analysis are still effective in suppressing the emittance growth when a more detailed one-dimensional CSR model is considered. In addition, it illustrates that the emittance growth can be reduced to a lower level with the proposed conditions than with the other two approaches, such as matching the beam envelope to the CSR kick and setting the cell-to-cell betatron phase advance to an appropriate value.

  19. Low Endogenous Fibroblast Growth Factor 2 Levels Are Associated With Heightened Conditioned Fear Expression in Rats and Humans.

    Science.gov (United States)

    Graham, Bronwyn M; Zagic, Dino; Richardson, Rick

    2017-10-15

    Hippocampal concentrations of the neurotrophic factor fibroblast growth factor 2 (FGF2) are negatively associated with the expression of fear following conditioning in rats. Heightened conditioned fear expression may be a prospective risk factor for the development of human anxiety and trauma disorders. However, the relationship between conditioned fear expression and FGF2 is yet to be established in humans. Using a cross-species approach, we first investigated the relationship between serum concentrations of FGF2 and individual differences in conditioned fear expression in rats (n = 19). We then subjected 88 human participants, who were recruited from university and community advertisements, to a differential fear conditioning procedure and assessed the relationship between salivary concentrations of FGF2 and fear expression to a conditioned stimulus (CS) (a stimulus paired with a shock) and a CS that was never paired with shock. Rats with low serum levels of FGF2 exhibited significantly more freezing than rats with high serum levels of FGF2. Similarly, relative to those with high salivary FGF2, human participants with low salivary FGF2 exhibited significantly heightened skin conductance responses to the CS without shock during fear conditioning and to both the CS with shock and CS without shock during fear recall. These studies establish that peripheral markers of FGF2 concentrations are negatively associated with fear expression in both rats and humans. To the extent that conditioned fear expression predicts anxiety and trauma disorder vulnerability, FGF2 may be a clinically useful biomarker in the prediction and eventual prevention of these disorders. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  20. The influence of the growth conditions of the plague microbe vaccine strain colonies on the fractal dimension of biospeckles

    International Nuclear Information System (INIS)

    Ul'yanov, A S; Lyapina, A M; Ulianova, O V; Fedorova, V A; Uianov, S S

    2011-01-01

    Specific statistical characteristics of biospeckles, emerging under the diffraction of coherent beams on the bacterial colonies, are studied. The dependence of the fractal dimensions of biospeckles on the conditions of both illumination and growth of the colonies is studied theoretically and experimentally. Particular attention is paid to the fractal properties of biospeckles, emerging under the scattering of light by the colonies of the vaccinal strain of the plague microbe. The possibility in principle to classify the colonies of Yersinia pestis EV NIIEG using the fractal dimension analysis is demonstrated. (optical technologies in biophysics and medicine)

  1. Effect of “Biosept 33 SL” on the growth of Phomopsis sojae Lehman in in vitro conditions

    Directory of Open Access Journals (Sweden)

    Elżbieta Patkowska

    2013-04-01

    Full Text Available The present studies determined the effect of preparation “Biosept 33 SL” in inhibiting the linear growth of five isolates of Phomopsis sojae in in vitro conditions. The experiment was conducted on PDA medium using the method of “the medium poisoning”. The examined preparation was used at the concentrations of 165, 330 and 660 μg grapefruit extract ∙cm -3 . The pathogen’s mycelium growing under the grapefruit extract was pale white, and the mycelium hyphae formed a fairly loose structure as distinct from the more compact mycelium of control colonies. Strong degeneration of mycelium hyphae was visible in microscopic preparations.

  2. Early growth response of six wheat varieties under artificial osmotic stress condition

    International Nuclear Information System (INIS)

    Khakwani, A.A.; Dennett, M.D.; Munir, M

    2011-01-01

    An experiment was carried out under laboratory conditions where seeds of six wheat varieties (Damani, Hashim-8, Gomal-8, DN-73, Zam-04 and Dera-98) were raised in Petri dishes and were either treated with distilled water (control) or 15% polyethylene glycol (PEG) 6000 solution. Seeds were treated with 15% PEG solution to establish an artificial osmotic stress condition (water stress) and observe its effect on germination percentage, coleoptile length, shoot and root length, fresh weight of shoot and root. A significant difference (P<0.05) was recorded between varietal and treatment means regarding all traits. Variety Hashim-8 gave maximum germination percentage (93.33%) whereas maximum coleoptile (1.78 cm) and shoot length (5.77 cm) was observed in variety DN-73 which was statistically at par with variety Hashim-8. Similarly, root length (3.63 g), fresh shoot (0.15 g) and root weight (0.12 g) was maximum in variety Dera-98 which was statistically at par with variety Hashim-8. A second experiment was carried out under glass house environment where plants were treated with non-stress (100% field capacity) and water stress (35% field capacity) treatments. Although total grain yield was significantly (P<0.05) reduced in all six wheat varieties when grown in water stress condition however Hashim-8 showed the lowest reduction (13%) while Zam-04 showed the highest (32%). The outcome of both experiments indicated that these varieties have great potential to incorporate with the existing commercial wheat varieties in order to obtain high yield in water stress regions. (author)

  3. Repair of UV damage in Escherichia coli under non-growth conditions

    International Nuclear Information System (INIS)

    Tang, M.-S.; Patrick, M.H.

    1977-01-01

    A large difference in survival occurred between buffered suspensions of E.coli irradiated with UV radiation at a low fluence rate and those irradiated at a high fluence rate. For sufficiently large fluences, the extent of this fluence rate dependent recovery (FRR) was about two orders of magnitude greater than that which could be brought about by liquid holding recovery (LHR) following high fluence rate irradiation in most of the E.coli strains studied. LHR and FRR occurred in excision resynthesis repair proficient (ERR + ) but not ERR - strains of E.coli, although its observation could be masked in strains with complete repair potential upon subsequent growth on nutrient plates. Accumulation of DNA strand interruptions and excision of cyclobutyl dipyrimidine occurred during LHR and FRR but were more extensive for the latter. The data suggest that events beyond incision and excision occurred during LHR and FRR, but differences in the extent of ERR during LHR and FRR could not account for the difference in cell survival between these two phenomena. (author)

  4. Halophilic archaea on Earth and in space: growth and survival under extreme conditions.

    Science.gov (United States)

    Oren, Aharon

    2014-12-13

    Salts are abundant on Mars, and any liquid water that is present or may have been present on the planet is expected to be hypersaline. Halophilic archaea (family Halobacteriaceae) are the microorganisms best adapted to life at extremes of salinity on Earth. This paper reviews the properties of the Halobacteriaceae that may make the group good candidates for life also on Mars. Many species resist high UV and gamma radiation levels; one species has survived exposure to vacuum and radiation during a space flight; and there is at least one psychrotolerant species. Halophilic archaea may survive for millions of years within brine inclusions in salt crystals. Many species have different modes of anaerobic metabolism, and some can use light as an energy source using the light-driven proton pump bacteriorhodopsin. They are also highly tolerant to perchlorate, recently shown to be present in Martian soils, and some species can even use perchlorate as an electron acceptor to support anaerobic growth. The presence of characteristic carotenoid pigments (α-bacterioruberin and derivatives) makes the Halobacteriaceae easy to identify by Raman spectroscopy. Thus, if present on Mars, such organisms may be detected by Raman instrumentation planned to explore Mars during the upcoming ExoMars mission. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  5. Effects of postharvest handling conditions on internalization and growth of Salmonella enterica in tomatoes.

    Science.gov (United States)

    Zhou, Bin; Luo, Yaguang; Nou, Xiangwu; Yang, Yang; Wu, Yunpeng; Wang, Qin

    2014-03-01

    Salmonella internalization in tomatoes during postharvest handling is a major food safety concern. This study was conducted to determine the effect of immersion time, immersion depth, and temperature differential between bacterial suspension and tomato pulp on the internalization of Salmonella enterica in tomato fruits. The effect of storage temperature and duration on the survival and growth of internalized Salmonella cells was also evaluated. Overall, immersion time significantly affected the incidence and extent of S. enterica internalization (P internalization. The depth of Salmonella internalization in tomato tissues also increased with increasing immersion time. Immersion time also significantly influenced the degree to which the temperature differential affected Salmonella internalization. With an immersion time of 2 min, the temperature differential had no significant effect on Salmonella internalization (P = 0.2536). However, with an immersion time of 15 min, a significantly larger Salmonella population became internalized in tomatoes immersed in solutions with a -30°F (-16.7°C) temperature differential. Internalized S. enterica cells persisted in the core tissues during 14 days of storage. Strain type and storage duration significantly affected (P internalized Salmonella recovered, but storage temperatures of 55 to 70°F (12.8 to 21.1°C) did not (P > 0.05). These findings indicate the importance of preventing pathogen internalization during postharvest handling.

  6. Effect of growth condition on biofilm formation by phenoldegrading bacteria isolated from polluted and nonpolluted sources

    Directory of Open Access Journals (Sweden)

    Arifah Khusnuryani

    2015-03-01

    Full Text Available Our previous research have isolated four phenol degrading bacteria. There are ATA6, DOK135, and DL120 which isolated from polluted source (hospital wastewater, also HP3 which isolated from non polluted source (peat soil. The purpose of this research is to analyze the effect of some environmental factors on the ability of four isolates to form biofilm. The environment factors were varied, such as growth medium, incubation temperature, and medium pH. Biofilm formation was measured using microtiter plate and crystal violet method, and the absorbance was read with microtiter auto reader at wavelenght 490 nm. The result showed that ATA6 was a strong biofilm former, DOK135 and HP3 were moderate biofilm former, and DL120 was a weak biofilm former. The results indicate that there is variation in the ability of selected isolates to form biofilm on various environmental factors. Generally, the isolates formed thicker biofilm in TSB medium which is a complex medium that provide more complete nutrient and formed biofilm optimally at 30oC. ATA6 formed biofilm optimally at pH 7 and HP3 at pH 9, while pH treatment did not affect on isolates DOK135 and DL120 to form biofilm.

  7. Repair of uv damage in Escherichia coli under non-growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tang, M S; Patrick, M H [Texas Univ., Dallas (USA)

    1977-09-01

    A large difference in survival occurred between buffered suspensions of E.coli irradiated with uv radiation at a low fluence rate and those irradiated at a high fluence rate. For sufficiently large fluences, the extent of this fluence rate dependent recovery (FRR) was about two orders of magnitude greater than that which could be brought about by liquid holding recovery (LHR) following high fluence rate irradiation in most of the E.coli strains studied. LHR and FRR occurred in excision resynthesis repair proficient (ERR/sup +/) but not ERR/sup -/ strains of E.coli, although its observation could be masked in strains with complete repair potential upon subsequent growth on nutrient plates. Accumulation of DNA strand interruptions and excision of cyclobutyl dipyrimidine occurred during LHR and FRR but were more extensive for the latter. The data suggest that events beyond incision and excision occurred during LHR and FRR, but differences in the extent of ERR during LHR and FRR could not account for the difference in cell survival between these two phenomena.

  8. Global existence and exponential growth for a viscoelastic wave equation with dynamic boundary conditions

    KAUST Repository

    Gerbi, Sté phane; Said-Houari, Belkacem

    2013-01-01

    The goal of this work is to study a model of the wave equation with dynamic boundary conditions and a viscoelastic term. First, applying the Faedo-Galerkin method combined with the fixed point theorem, we show the existence and uniqueness of a local in time solution. Second, we show that under some restrictions on the initial data, the solution continues to exist globally in time. On the other hand, if the interior source dominates the boundary damping, then the solution is unbounded and grows as an exponential function. In addition, in the absence of the strong damping, then the solution ceases to exist and blows up in finite time.

  9. Global existence and exponential growth for a viscoelastic wave equation with dynamic boundary conditions

    KAUST Repository

    Gerbi, Stéphane

    2013-01-15

    The goal of this work is to study a model of the wave equation with dynamic boundary conditions and a viscoelastic term. First, applying the Faedo-Galerkin method combined with the fixed point theorem, we show the existence and uniqueness of a local in time solution. Second, we show that under some restrictions on the initial data, the solution continues to exist globally in time. On the other hand, if the interior source dominates the boundary damping, then the solution is unbounded and grows as an exponential function. In addition, in the absence of the strong damping, then the solution ceases to exist and blows up in finite time.

  10. Effect of Different Nitrogen Levels on Phenology, Growth Indices and Yield of two Lentil Cultivars under Rainfed Conditions in Mashhad

    Directory of Open Access Journals (Sweden)

    M Bannayan Aval

    2018-02-01

    Full Text Available Introduction Lentil (Lens Culinarris Medik. is an important pulse crop in Iran and is usually grown in rainfed areas. The average lentil yield in Iran is 1195 and 476 Kg.ha-1 in irrigated and rainfed farms, respectively. Low productivity occurs due to different factors. One of these factors is poor agronomic management practices that applied by the farmers, e.g. Limitation or inappropriate fertilizer distribution. Plant development occurs in a number of consecutive phases. These phases can be affected by temperature, moisture, photoperiod, cultivar and other factors. The amount of available nitrogen affects the distribution of assimilates between vegetative and reproductive organs and phenological stages of growth. Therefore, analysis of growth indices and its effective factors can be used as a suitable tool in evaluating the yield. The aim of this study was to evaluate the effect of different nitrogen levels on phenology and growth indices of two lentil cultivars in rainfed conditions of Mashhad. Materials and Methods The experiment was conducted as split plot layout based on randomized complete blocks design with three replications at the Agricultural Research Station, Ferdowsi University of Mashhad, during growth season 2016. Nitrogen fertilizer as urea (in three levels i.e. 0, 40 and 80 kg.ha-1 and cultivar (in two levels i.e. Birjand and Robat were in main plots and sub plots, respectively. To determine the leaf area and dry matter, sampling was done every two weeks during the growing season. Phenological stages timing for each plot were determined based on 50% of emergence, 50% of flowering, 50% of maturity. Final yield was estimated from three square meter from each plot. Data were analyzed with the SAS software; the means were compared with Duncan's multiple range tests at the 5% level of probability. The graphs were prepared by SigmaPlot software. Results and Discussion The results showed that the effect of urea fertilizer was

  11. The effects of food and maternal conditions in fetal growth and size in wild reindeer

    Directory of Open Access Journals (Sweden)

    Terje Skogland

    1984-05-01

    Full Text Available Fetal growth rates and birth weights were studied in four wild reindeer areas in Southern Norway (Hardangervidda, Hallingskarvet, Knutshø, Forelhogna, representing high and low density populations, with a 5-fold difference in mean lichen winter-food availability. Fetal growth was depressed by 42% in the high-densitv Hardangervidda population, and mean birth weights were 3.7 vs. 6.2 kg, with a 10 days difference in mean birth dates. Fetal size was better correlated with maternal weight, than age. Maternal weights increased until 5 yrs. of age and then decreased in the high-density Hardangervidda population (but not so in the low density Knutshø-Forclhogna populations. 55% of the offspring died before weaning in the Hardangervidda herd, but no significant calf losses were found amont the large-sized does in the food-abundant areas.Effekter av ernæring og simlas kondisjon på vekst og størrelse av foster hos villrein.Abstract in Norwegian / Sammendrag: Fostervekst og fødselsvekter ble undersøkt i fire villreinområder i Sør-Norge (Hardangervidda, Hallingskarvet, Knutshø og Forelhogna som representerer høg- og lågtetthetsstammer, med en 5-foldig forskjell i gjennomsnittlig lavbeite-tilgang om vinteren. Fosterveksten ble nedsatt med 42% i høgtetthetsstammen på Hardangervidda og fødselsvektene var i gjennomsnitt 3,7 kg, mot 6,2 kg i det beste området, og med en 10 dagers forsinkelse i midlere fødselsdato. Fosterets størrelse var korrelert med morens vekt, som igjen var avhengig av hennes alder. Hos de minste simlene i det dårligste området økte vektene til 5-års alder, for deretter å avta for hvert gjenlevende år. Hos simlene i det beste området økte vektene til 10-års alder, og var da dobbelt så tunge som fra det dårligste området. 55% av avkommet døde før de var avvent med diing hos Hardangervidda-simlene, mens det ikke var noen statistisk målbar dødelighet hos kalvene i Knutshø-Forelhogna.Ravinnon vaikutus ja

  12. Correlation between Strawberry (Fragaria ananassa Duch. Productivity and Photosynthesis-related Parameters under Various Growth Conditions

    Directory of Open Access Journals (Sweden)

    Hyo Gil Choi

    2016-10-01

    Full Text Available In the present study, we investigated changes in chlorophyll fluorescence, photosynthetic parameters and fruit yields, as well as fruit phytochemical accumulation of strawberry (Fragaria ananassa Duch. that had been cultivated in a greenhouse under different combinations of light intensity and temperature. In plants grown with low light (LL photosystem II chlorophyll fluorescence was found to increase as compared with those grown under high light (HL. When strawberry plants were grown with temperature higher than 5◦C in addition to LL, they showed decrease in non-photochemical quenching (NPQ, photochemical quenching (qP, as well as chlorophyll fluorescence decrease ratio (RFd when compared with other combinations of light and temperature. Moreover, fruit yield of strawberry was closely correlated with chlorophyll fluorescence-related parameters such as NPQ, qP, and RFd, but not with the maximum efficiency of PS II (Fv/Fm. Although plant groups grown under different combinations of light and temperature showed almost comparable levels of photosynthesis rates (Pr when irradiated with low-intensity light, they displayed clear differences when measured with higher irradiances. Plants grown under HL with temperature above 10◦C showed the highest Pr, in contrast to the plants grown under LL with temperature above 5◦C. When the stomatal conductance and the transpiration rate were measured, plants of each treatment showed clear differences even when analyzed with lower irradiances. We also found that fruit production during winter season was more strongly influenced by growth temperature than light intensity. We suggest that fruit productivity of strawberry is closely associated with chlorophyll fluorescence and photosynthesis-related parameters during cultivation under different regimes of temperature and light.

  13. Allelopathic Effects of Four Chickpea Cultivars on Vegetative Growth of Sunflower and Corn under Controlled Conditions

    Directory of Open Access Journals (Sweden)

    k Hajmohammadnia Ghalibaf

    2011-02-01

    Full Text Available Abstract In order to study the effects of four chickpea cultivar (Cicer arietinum L. on vegetative growth of sunflower (Helianthus annus and corn (Zea mays, two separate experiments was conducted at Research Greenhouse of Ferdowsi University of Mashhad in 2005. Experiments were done in a factorial arrangement of treatments with two factors based on completely randomized design with 4 replications. Factors included chickpea cultivars (Karag12-60-31, Filip 84-482, Gam, ILC 482, and no residue control and planting date of corn and sunflowers within root residues of chick pea (seeds planted simultaneously, 2 weeks, and 4 weeks after harvesting of chickpea shoots. Seeds of corn and sunflower were planted within root residues of chickpea. Results showed that root residues of chickpea cultivars influenced height and shoot weight of sunflower significantly. The lowest sunflower height was obtained when they were planted within root residues of Flip and ILC cultivars, which decreased 13.7 and 11.1% relative to control, respectively. Planting date of sunflower within root residues of chick pea cultivars had a significant effect on sunflower leaf area, shoot weight, and its root/shoot ratio. So that, lowest leaf area, shoot weight, and also highest root/shoot ratio was obtained in third planting date. Results showed that lowest plant height, leaf area, root weight, shoot weight, and also highest root/shoot ratio of corn (6 weeks after planting was obtained after planting within chickpea cultivars, Gam and ILC. Also the effect of corn planting date was significant. The lowest root and shoot weight, and root/shoot ratio of corn was obtained in the earliest corn planting date. Therefore, corn plants showed more sensitive than sunflower after planting within chickpea cultivars, and the highest inhibitory effects resulted in the earliest corn planting date. Keywords: Pea cultivars, Integrated management, Crop rotation

  14. Identifying Growth Conditions for Nicotiana benthimiana Resulting in Predictable Gene Expression of Promoter-Gus Fusion

    Science.gov (United States)

    Sandoval, V.; Barton, K.; Longhurst, A.

    2012-12-01

    Revoluta (Rev) is a transcription factor that establishes leaf polarity inArabidopsis thaliana. Through previous work in Dr. Barton's Lab, it is known that Revoluta binds to the ZPR3 promoter, thus activating the ZPR3 gene product inArabidopsis thaliana. Using this knowledge, two separate DNA constructs were made, one carrying revgene and in the other, the ZPR3 promoter fussed with the GUS gene. When inoculated in Nicotiana benthimiana (tobacco), the pMDC32 plasmid produces the Rev protein. Rev binds to the ZPR3 promoter thereby activating the transcription of the GUS gene, which can only be expressed in the presence of Rev. When GUS protein comes in contact with X-Gluc it produce the blue stain seen (See Figure 1). In the past, variability has been seen of GUS expression on tobacco therefore we hypothesized that changing the growing conditions and leaf age might improve how well it's expressed.

  15. The endophytic fungus Piriformospora indica enhances Arabidopsis thaliana growth and modulates Na+/K+ homeostasis under salt stress conditions.

    Science.gov (United States)

    Abdelaziz, Mohamed E; Kim, Dongjin; Ali, Shawkat; Fedoroff, Nina V; Al-Babili, Salim

    2017-10-01

    The mutualistic, endophytic fungus Piriformospora indica has been shown to confer biotic and abiotic stress tolerance to host plants. In this study, we investigated the impact of P. indica on the growth of Arabidopsis plants under normal and salt stress conditions. Our results demonstrate that P. indica colonization increases plant biomass, lateral roots density, and chlorophyll content under both conditions. Colonization with P. indica under salt stress was accompanied by a lower Na + /K + ratio and less pronounced accumulation of anthocyanin, compared to control plants. Moreover, P. indica colonized roots under salt stress showed enhanced transcript levels of the genes encoding the high Affinity Potassium Transporter 1 (HKT1) and the inward-rectifying K + channels KAT1 and KAT2, which play key roles in regulating Na + and K + homeostasis. The effect of P. indica colonization on AtHKT1;1 expression was also confirmed in the Arabidopsis line gl1-HKT:AtHKT1;1 that expresses an additional AtHKT1;1 copy driven by the native promoter. Colonization of the gl1-HKT:AtHKT1;1 by P. indica also increased lateral roots density and led to a better Na + /K + ratio, which may be attributed to the observed increase in KAT1 and KAT2 transcript levels. Our findings demonstrate that P. indica colonization promotes Arabidopsis growth under salt stress conditions and that this effect is likely caused by modulation of the expression levels of the major Na + and K + ion channels, which allows establishing a balanced ion homeostasis of Na + /K + under salt stress conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. ARBUSCULAR MYCORRHIZAL FUNGI INCREASED EARLY GROWTH OF GAHARU WOOD OF Aquilaria malaccencsis and A. crasna UNDER GREENHOUSE CONDITIONS

    Directory of Open Access Journals (Sweden)

    Maman Turjaman

    2006-07-01

    Full Text Available Gaharu wood stand has an important source of profits to the forest community in South and Southeast Asia tropical forest countries, but Aquilaria species have reduced in number and turn out to be endangered due to overexploitation.   Today,   the planting stocks of   Aquilaria species are not sufficient to sustain the yield of gaharu wood and promote forest conservation.  The objective of this study was to determine   the effect of   five arbuscular mycorrhizal (AM fungi: Entrophospora sp., Gigaspora decipiens, Glomus clarum, Glomus sp. ZEA, and Glomus sp. ACA, on the early growth of  Aquilaria malaccensis and A. crasna under greenhouse conditions. The seedlings of  Aquilaria spp. were inoculated with Entrophospora sp., Gi. decipiens, Glomus clarum, Glomus sp. ZEA, Glomus sp. ACA and uninoculated (control under greenhouse conditions. Then, percentage AM colonization, plant growth, survival rate and nitrogen (N and phosphorus (P content and mycorrhizal dependence (MD were measured. The percentage AM colonization of A. malaccensis and A. crasna ranged from 83 to 97% and from 63 to 78%, respectively. Colonization by five AM fungi increased plant height, diameter, and shoot and root dry weights. N and P content of  the seedlings were also increased by AM colonization. Survival rates were higher in the AM-colonized seedlings at 180 days after transplantation than those in the control seedlings. The MD of Aquilaria species was higher than 55 %. The results suggested that AM fungi can be inoculated`to Aquilaria species under nursery conditions to obtain vigorous seedlings, and the field experiment is underway to clarify the role of AM fungi under field conditions.

  17. The endophytic fungus Piriformospora indica enhances Arabidopsis thaliana growth and modulates Na + /K + homeostasis under salt stress conditions

    KAUST Repository

    Abdelaziz, Mohamed Ewis

    2017-07-13

    The mutualistic, endophytic fungus Piriformospora indica has been shown to confer biotic and abiotic stress tolerance to host plants. In this study, we investigated the impact of P. indica on the growth of Arabidopsis plants under normal and salt stress conditions. Our results demonstrate that P. indica colonization increases plant biomass, lateral roots density, and chlorophyll content under both conditions. Colonization with P. indica under salt stress was accompanied by a lower Na+/K+ ratio and less pronounced accumulation of anthocyanin, compared to control plants. Moreover, P. indica colonized roots under salt stress showed enhanced transcript levels of the genes encoding the high Affinity Potassium Transporter 1 (HKT1) and the inward-rectifying K+ channels KAT1 and KAT2, which play key roles in regulating Na+ and K+ homeostasis. The effect of P. indica colonization on AtHKT1;1 expression was also confirmed in the Arabidopsis line gl1-HKT:AtHKT1;1 that expresses an additional AtHKT1;1 copy driven by the native promoter. Colonization of the gl1-HKT:AtHKT1;1 by P. indica also increased lateral roots density and led to a better Na+/K+ ratio, which may be attributed to the observed increase in KAT1 and KAT2 transcript levels. Our findings demonstrate that P. indica colonization promotes Arabidopsis growth under salt stress conditions and that this effect is likely caused by modulation of the expression levels of the major Na+ and K+ ion channels, which allows establishing a balanced ion homeostasis of Na+/K+ under salt stress conditions.

  18. Effects of culture conditions on the growth and reproduction of Gut Weed, Ulva intestinalis Linnaeus (Ulvales, Chlorophyta

    Directory of Open Access Journals (Sweden)

    Rapeeporn Ruangchuay

    2012-11-01

    Full Text Available In vitro cultivation of Gut Weed, Ulva intestinalis Linnaeus, was experimentally studied to support its near optimalfarming, with potential impact in Thailand on its direct use as human food or its co-cultures in shrimp farming.Germling clusters (2 weeks old and 7.50±2.98 mm long were seeded into 500 mL flasks and biomass growth rateoptimized with respect to the main controllable factors; seedling density, salinity, light intensity, and temperature. These factorswere assumed to each have an optimal value independent of the others, and the factors were optimized one at a time. Themaximum growth at three to four weeks of cultivation was obtained at the factor levels of 0.05 gL-1, 20 ppt, 80 mol photonm-2s-1 and 25°C. Early zoosporangia were obtained from 2nd to 4th weeks. The relative growth rate ranged from 9.47 to 22.18 %day-1, and only asexual reproduction of U. intestinalis was observed under these culture conditions.

  19. Elevated Atmospheric CO2 and Warming Stimulates Growth and Nitrogen Fixation in a Common Forest Floor Cyanobacterium under Axenic Conditions

    Directory of Open Access Journals (Sweden)

    Zoë Lindo

    2017-03-01

    Full Text Available The predominant input of available nitrogen (N in boreal forest ecosystems originates from moss-associated cyanobacteria, which fix unavailable atmospheric N2, contribute to the soil N pool, and thereby support forest productivity. Alongside climate warming, increases in atmospheric CO2 concentrations are expected in Canada’s boreal region over the next century, yet little is known about the combined effects of these factors on N fixation by forest floor cyanobacteria. Here we assess changes in N fixation in a common forest floor, moss-associated cyanobacterium, Nostoc punctiforme Hariot, under elevated CO2 conditions over 30 days and warming combined with elevated CO2 over 90 days. We measured rates of growth and changes in the number of specialized N2 fixing heterocyst cells, as well as the overall N fixing activity of the cultures. Elevated CO2 stimulated growth and N fixation overall, but this result was influenced by the growth stage of the cyanobacteria, which in turn was influenced by our temperature treatments. Taken together, climate change factors of warming and elevated CO2 are expected to stimulate N2 fixation by moss-associated cyanobacteria in boreal forest systems.

  20. Non-thermal plasma modified growth and differentiation process of Capsicum annuum PP805 Godiva in in vitro conditions

    Science.gov (United States)

    Safari, Nasrin; Iranbakhsh, Alireza; Ardebili, Zahra Oraghi

    2017-05-01

    With the aim of evaluating the possible impacts of cold plasma on the structure and growth pattern of Capsicum annuum, the current study was carried out. The seeds were exposed to an argon-derived plasma (0.84 W cm-2 surface power densities) for 0, 1 or 2 minutes. Plasma-treated seeds were grown in the Murashige and Skoog (MS) medium or MS medium supplemented with BA and IAA. The presence of purple stems was recorded in plasma-treated plants grown in the medium supplemented with hormones. The recorded morphological differences were dependent on the exposure time of plasma treatments and/or the presence of hormones in the culture media. Plasma treatment of 1 minute had an improving effect on the shoot and root lengths as well as total leaf area, whereas plasma treatment of 2 minutes had an adverse effect. In contrast to the 1 minute treatment, plasma treatment of 2 minutes significantly impaired growth and hence reduced the total biomass. Alterations in stem diameter and differences in tissue patterns (especially in the vascular system) occurred, and were mainly dependent on the plasma exposure time and/or the presence of hormones. This is a first report on the effects of cold plasma on plant growth in in vitro conditions.

  1. The human growth and the healthy environment as a condition of balanced development for the course of human.

    Directory of Open Access Journals (Sweden)

    I. Koukoumpliakos

    2008-01-01

    Full Text Available The rising standard of living has evoked an important burden in the natural environment leading to an immense deterioration of nature. The pollution of the atmosphere and seas, the industrial waste, the climatic changes, the chaotic built-up extension threaten the health of all of us. The responsibility for the pollution of the environment is allocated in everybody. The State is accountable not only for the political planning and the policy that practises, but also for the frame it shapes for the citizens to follow. The improvement of the quality of environment must be combined with the economic progress and growth. The intensity of environmental problems worries the International Community, while the saving and growth of new green forms of energy appear as imperative need. We find already ourselves in a progressive but continuous growth, which has the conditions to develop in the future with spectacular rhythm.The methodology of present work is recommended for: a bibliographic research, mainly Greek, b comparison of the facts that are exported from research, connecting them with the given facts. This comparison leads to the necessary coexistence of a healthy environment and a viable growth.In the results of the research the essential conditions of coexistence are presented between these two. Thus we realise that: a the configuration of an evener environmental conscience is required via the education which would guarantee the balanced and sustainable growth, b the change of perception of people as lords of nature is considered necessary and its replacement by the awareness that the nature does not constitute an inexhaustible resource.With that in mind we conclude that: a the research is required to lead to alternative sources of energy such as the creation of Aeolian parks. It is estimated that more investments in other types of renewable sources of energy such as geothermal and hydroelectric can constitute also advisable solutions. The use of

  2. Crack growth behaviour of low alloy steels for pressure boundary components under transient light water reactor operating conditions (CASTOC)

    International Nuclear Information System (INIS)

    Foehl, J.; Weissenberg, T.; Gomez-Briceno, D.; Lapena, J.; Ernestova, M.; Zamboch, M.; Seifert, H.P.; Ritter, S.; Roth, A.; Devrient, B.; Ehrnsten, U.

    2004-01-01

    The CASTOC project addresses environmentally assisted cracking (EAC) phenomena in low alloy steels used for pressure boundary components in both Western type boiling water reactors (BWR) and Russian type pressurised water reactors (VVER). It comprises the four work packages (WP): inter-laboratory comparison test (WP1); EAC behaviour under static load (WP2), EAC behaviour under cyclic load and load transients (WP3); evaluation of the results with regard to their relevance for components in practice (WP4). The use of sophisticated test facilities and measurement techniques for the on-line detection of crack advances have provided a more detailed understanding of the mechanisms of environmentally assisted cracking and provided quantitative data of crack growth rates as a function of loading events and time, respectively. The effect of several major parameters controlling EAC was investigated with particular emphasis on the transferability of the results to components in service. The obtained crack growth rate data were reflected on literature data and on commonly applied prediction curves as presented in the appropriate Code. At relevant stress intensity factors it could be shown that immediate cessation of growing cracks occurs after changing from cyclic to static load in high purity oxygenated BWR water and oxygen-free VVER water corresponding to steady state operation conditions. Susceptibility to environmentally assisted cracking under static load was observed for a heat affected zone material in oxygenated high purity water and also in base materials during a chloride transient representing BWR water condition below Action Level 1 of the EPRI Water Chemistry Guidelines according to the lectrical conductivity of the water but in the range of Action Level 2 according to the content of chlorides. Time based crack growth was also observed in one Russian type base material in oxygenated VVER water and in one Western type base material in oxygenated high purity BWR

  3. Effect of the growth conditions on the anisotropy, domain structures and the relaxation in Co thin films

    Energy Technology Data Exchange (ETDEWEB)

    Mallik, Srijani; Mallick, Sougata; Bedanta, Subhankar, E-mail: sbedanta@niser.ac.in

    2017-04-15

    We report a systematic study on the anisotropy symmetry, magnetic domains and magnetic relaxation behavior in Co thin films deposited on MgO (001) substrate by varying (i) the pre-annealing condition and (ii) the speed of substrate rotation during deposition. Substrate annealing prior to deposition leads to the formation of textured thin films. On contrary Co films prepared without substrate pre-annealing exhibit polycrystalline nature. Surface topography imaged by atomic force microscopy (AFM) depicts a profound effect of growth condition on grain size and its distribution. Magnetic hysteresis measurement along with simultaneous domain imaging has been performed by magneto optic Kerr effect (MOKE) based microscope by varying the angle (ϕ) between the easy axis and the direction of applied magnetic field. We observed the existence of cubic and uniaxial anisotropy due to the presence of substrate annealing and oblique angular deposition, respectively. Along the easy axis, magnetization reversal is governed by 180° domain wall motion via branched domains. However, for easy axis<ϕgrowth of Co on MgO(001) substrate. • The structure has clear implication on the magnetic properties. • The magnetic relaxation has been studied for both textured and polycrystalline films.

  4. Optimization of experimental conditions for the monitoring of nucleation and growth of racemic Diprophylline from the supercooled melt

    Science.gov (United States)

    Lemercier, Aurélien; Viel, Quentin; Brandel, Clément; Cartigny, Yohann; Dargent, Eric; Petit, Samuel; Coquerel, Gérard

    2017-08-01

    Since more and more pharmaceutical substances are developed as amorphous forms, it is nowadays of major relevance to get insights into the nucleation and growth mechanisms from supercooled melts (SCM). A step-by-step approach of recrystallization from a SCM is presented here, designed to elucidate the impact of various experimental parameters. Using the bronchodilator agent Diprophylline (DPL) as a model compound, it is shown that optimal conditions for informative observations of the crystallization behaviour from supercooled racemic DPL require to place samples between two cover slides with a maximum sample thickness of 20 μm, and to monitor recrystallization during an annealing step of 30 min at 70 °C, i.e. about 33 °C above the temperature of glass transition. In these optimized conditions, it could be established that DPL crystallization proceeds in two steps: spontaneous nucleation and growth of large and well-faceted particles of a new crystal form (primary crystals: PC) and subsequent crystallization of a previously known form (RII) that develops from specific surfaces of PC. The formation of PC particles therefore constitutes the key-step of the crystallization events and is shown to be favoured by at least 2.33 wt% of the major chemical impurity, Theophylline.

  5. Inhibition of calcium carbonate crystal growth by organic additives using the constant composition method in conditions of recirculating cooling circuits

    Science.gov (United States)

    Chhim, Norinda; Kharbachi, Chams; Neveux, Thibaut; Bouteleux, Céline; Teychené, Sébastien; Biscans, Béatrice

    2017-08-01

    The cooling circuits used in power plants are subject to mineral crystallization which can cause scaling on the surfaces of equipment and construction materials reducing their heat exchange efficiency. Precipitated calcium carbonate is the predominant mineral scale commonly observed in cooling systems. Supersaturation is the key parameter controlling the nucleation and growth of calcite in these systems. The present work focuses on the precipitation of calcite using the constant composition method at constant supersaturation, through controlled addition of reactants to a semi-batch crystallizer, in order to maintain constant solution pH. The determination of the thermodynamic driving force (supersaturation) was based on the relevant chemical equilibria, total alkalinity and calculation of the activity coefficients. Calcite crystallization rates were derived from the experiments performed at supersaturation levels similar to those found in industrial station cooling circuits. Several types of seeds particles were added into the aqueous solution to mimic natural river water conditions in terms of suspended particulate matters content, typically: calcite, silica or illite particles. The effect of citric and copolycarboxylic additive inhibitors added to the aqueous solution was studied. The calcium carbonate growth rate was reduced by 38.6% in the presence of the citric additive and a reduction of 92.7% was observed when the copolycarboxylic additive was used under identical experimental conditions. These results are explained by the location of the adsorbed inhibitor at the crystal surface and by the degree of chemical bonding to the surface.

  6. Growth, photosynthesis and antioxidant responses of endophyte infected and non-infected rice under lead stress conditions.

    Science.gov (United States)

    Li, Xuemei; Bu, Ning; Li, Yueying; Ma, Lianju; Xin, Shigang; Zhang, Lihong

    2012-04-30

    An endophytic fungus was tested in rice (Oryza sativa L.) exposed to four levels of lead (Pb) stress (0, 50, 100 and 200 μM) to assess effects on plant growth, photosynthesis and antioxidant enzyme activity. Under Pb stress conditions, endophyte-infected seedlings had greater shoot length but lower root length compared to non-infected controls, and endophyte-infected seedlings had greater dry weight in the 50 and 100 μM Pb treatments. Under Pb stress conditions, chlorophyll and carotenoid levels were significantly higher in the endophyte-infected seedlings. Net photosynthetic rate, transpiration rate and water use efficiency were significantly higher in endophyte-infected seedlings in the 50 and 100 μM Pb treatments. In addition, chlorophyll fluorescence parameters Fv/Fm and Fv/Fo were higher in the infected seedlings compared to the non-infected seedlings under Pb stress. Malondialdehyde accumulation was induced by Pb stress, and it was present in higher concentration in non-infected seedlings under higher concentrations of Pb (100 and 200 μM). Antioxidant activity was either higher or unchanged in the infected seedlings due to responses to the different Pb concentrations. These results suggest that the endophytic fungus improved rice growth under moderate Pb levels by enhancing photosynthesis and antioxidant activity relative to non-infected rice. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Patterns of growth and body condition in sea otters from the Aleutian archipelago before and after the recent population decline

    Science.gov (United States)

    Laidre, K.L.; Estes, J.A.; Tinker, M.T.; Bodkin, James L.; Monson, Daniel H.; Schneider, K.

    2006-01-01

    1. Growth models for body mass and length were fitted to data collected from 1842 sea otters Enhydra lutris shot or live-captured throughout south-west Alaska between 1967 and 2004. Growth curves were constructed for each of two main year groups: 1967–71 when the population was at or near carrying capacity and 1992–97 when the population was in steep decline. Analyses of data collected from animals caught during 2004, when the population density was very low, were precluded by a small sample size and consequently only examined incidentally to the main growth curves.2. Growth curves demonstrated a significant increase in body mass and body length at age in the 1990s. Asymptotic values of body mass were 12–18% higher in the 1990s than in the 1960s/70s, and asymptotic values for body length were 10–11% higher between the same periods. Data collected in 2004 suggest a continued increase in body size, with nearly all data points for mass and length falling significantly above the 1990s growth curves.3. In addition to larger asymptotic values for mass and length, the rate of growth towards asymptotic values was more rapid in the 1990s than in the 1960s/70s: sea otters reached 95% of asymptotic body mass and body length 1–2 years earlier in the 1990s.4. Body condition (as measured by the log mass/log length ratio) was significantly greater in males than in females. There was also an increasing trend from the 1960s/70s through 2004 despite much year-to-year variation.5. Population age structures differed significantly between the 1960s/70s and the 1990s with the latter distribution skewed toward younger age classes (indicating an altered lxfunction) suggesting almost complete relaxation of age-dependent mortality patterns (i.e. those typical of food-limited populations).6. This study spanned a period of time over which the population status of sea otters in the Aleutian archipelago declined precipitously from levels at or near equilibrium densities at

  8. Effect of less intensive rearing conditions on litter characteristics, growth performance, carcase injuries and meat quality of broilers.

    Science.gov (United States)

    Meluzzi, A; Fabbri, C; Folegatti, E; Sirri, F

    2008-09-01

    1. The objective was to compare the effect of two litter types (wheat straw and wood shavings) and two different rearing conditions (Treated and Control) on welfare indicators, broiler performance, carcase injuries, particularly hock and foot pad dermatitis (FPD), litter characteristics and meat quality. 2. Treated conditions were characterised by a low stocking density (11 birds/m(2)), short photoperiod (16 h light: 8 h dark) and a large amount of litter (3 to 4.5 kg/m(2), respectively, for wheat straw or wood shavings). Control conditions were a high stocking density (14 birds/m(2)), long photoperiod (23 h light:1 h dark) and small amount of litter (2.3 to 3 kg/m(2), respectively, for wheat straw or wood shavings). In addition, the effects of two widely used litter materials, wheat straw and wood shavings, were investigated. 3. The combined effects of lower stocking density, greater amount of litter material and a photoperiod similar to the natural one, reduced the occurrence of FPD in Treated groups keeping the FPD score under the European threshold. 4. Improved rearing conditions led to faster growth rate associated with inferior feed efficiency, whereas litter type exerted negligible effects on broiler performance. 5. Litter moisture content, nitrogen and ammonia released by the litter were lower in Treated groups than Control groups. The use of wood shavings resulted in lower moisture and nitrogen concentrations in the litter.

  9. Effects of H2O2 under low- and high-aeration-level conditions on growth and catalase activity in Exiguobacterium oxidotolerans T-2-2T.

    Science.gov (United States)

    Takebe, Fumihiko; Hara, Isao; Matsuyama, Hidetoshi; Yumoto, Isao

    2007-12-01

    The effects of H2O2 under low- and high-aeration-level conditions on growth and catalase activity in Exiguobacterium oxidotolerans T-2-2T were investigated. Continuous addition of 5-200 mM H2O2 to the culture medium from the mid-exponential growth phase enhanced the growth of the strain under the low-aeration-level condition, whereas the addition of 5-50 mM H2O2 decreased intracellular specific catalase activity and extracellular total catalases activity. The detection of extracellular catalase by the cells and the decrease in intracellular specific catalase activity and extracellular total catalase activity under the high-aeration-level condition account for the stimulation of growth by the introduced H2O2 and the decrease in catalase activities induced by O(2) from H2O2 in the medium. On the other hand, the addition of H2O2 to the medium prior to the initiation of growth inhibited the growth but increased the specific activity of intracellular catalase in the stationary growth phase. Strain T-2-2T grew when 10 mM H2O2 was added to the medium prior to growth. However, the growth was completely inhibited by the catalase inhibitor 3-amino-1,2,4-triazole (3-AT). The continuous addition of H2O2 at an appropriate concentration from prior to the initiation of growth to the stationary growth phase under the low-aeration-level condition resulted in higher intracellular specific catalase activity and cell growth rate than single H2O2 addition prior to growth.

  10. All three quinone species play distinct roles in ensuring optimal growth under aerobic and fermentative conditions in E. coli K12

    Science.gov (United States)

    Nitzschke, Annika

    2018-01-01

    The electron transport chain of E. coli contains three different quinone species, ubiquinone (UQ), menaquinone (MK) and demethylmenaquinone (DMK). The content and ratio of the different quinone species vary depending on the external conditions. To study the function of the different quinone species in more detail, strains with deletions preventing UQ synthesis, as well as MK and/or DMK synthesis were cultured under aerobic and anaerobic conditions. The strains were characterized with respect to growth and product synthesis. As quinones are also involved in the control of ArcB/A activity, we analyzed the phosphorylation state of the response regulator as well as the expression of selected genes.The data show reduced aerobic growth coupled to lactate production in the mutants defective in ubiquinone synthesis. This confirms the current assumption that ubiquinone is the main quinone under aerobic growth conditions. In the UQ mutant strains the amount of MK and DMK is significantly elevated. The strain synthesizing only DMK is less affected in growth than the strain synthesizing MK as well as DMK. An inhibitory effect of MK on aerobic growth due to increased oxidative stress is postulated.Under fermentative growth conditions the mutant synthesizing only UQ is severely impaired in growth. Obviously, UQ is not able to replace MK and DMK during anaerobic growth. Mutations affecting quinone synthesis have an impact on ArcA phosphorylation only under anaerobic conditions. ArcA phosphorylation is reduced in strains synthesizing only MK or MK plus DMK. PMID:29614086

  11. Growth, chamber building rate and reproduction time of Palaeonummulites venosus (Foraminifera) under natural conditions

    Science.gov (United States)

    Kinoshita, Shunichi; Eder, Wolfgang; Wöger, Julia; Hohenegger, Johann; Briguglio, Antonino

    2017-12-01

    We investigated the symbiont-bearing benthic foraminifer Palaeonummulites venosus to determine the chamber building rate (CBR), test diameter increase rate (DIR), reproduction time and longevity using the `natural laboratory' approach. This is based on the decomposition of monthly obtained frequency distributions of chamber number and test diameter into normally distributed components. Test measurements were taken using MicroCT. The shift of the mean and standard deviation of component parameters during the 15-month investigation period was used to calculate Michaelis-Menten functions applied to estimate the averaged CBR and DIR under natural conditions. The individual dates of birth were estimated using the inverse averaged CBR and the inverse DIR fitted by the individual chamber number or the individual test diameter at the sampling date. Distributions of frequencies and densities (i.e., frequency divided by sediment weight) based on both CBR and DIR revealed continuous reproduction throughout the year with two peaks, a stronger one in June determined as the onset of the summer generation (generation 1) and a weaker one in November determined as the onset of the winter generation (generation 2). This reproduction scheme explains the presence of small and large specimens in the same sample. Longevity, calculated as the maximum difference in days between the individual's birth date and the sampling date, is approximately 1.5 yr, an estimation obtained by using both CBR and DIR.

  12. Vegetative anatomical adaptations of Epidendrum radicans (Epidendroideae, Orchidaceae to epiphytic conditions of growth

    Directory of Open Access Journals (Sweden)

    Muthukumar Thangavelu

    2017-12-01

    Full Text Available The anatomical properties of leaf, stem, and root of Epidendrum radicans Pav. ex Lindl., belonging to the subfamily Epidendroideae (Orchidaceae were investigated for adaptations to stressed habitats. The anatomical investigation revealed that leaves of E. radicans have a thick cuticle (3–4 µm and paracytic type of stomata. Foliar epidermal cells are conical on the adaxial surface and rectangular in the abaxial surface, distinct hypodermis absent, and uniseriate fiber bundles are arranged in both sides of the leaves. The foliar mesophyll is homogenous and starch grains and raphides present. The leaf sheath covering the stem have cuticle restricted to the outer surface and air spaces are present. The stem has a cuticulerized uniseriate epidermis and a uniseriate hypodermis. The cortex and a parenchymatous ground tissue of the stem are separated by a layer of sclerenchymatous band. Vascular bundles are collateral and their size generally increases from the periphery towards the center. A sclerenchymatous patch covers the phloem pole, whereas the xylem is covered by thin-walled parenchymatous cells. The roots possess Epidendrum-type velamen. Cover cells present. Uniseriate dimorphic exodermis consists of U-thickened long cells and thin-walled passage cells. The endodermal cells O-thickened, pericycle sclerenchymatous, xylem 10–14 arched. The pith is sclerenchymatous, but parenchymatous at the center. The anatomical examination of E. radicans revealed adaptations to moisture stress conditions like thick cuticle covering the leaves and stem, water storage cells, multilayered velamen and dimorphic exodermis.

  13. Renewed growth in hospital inpatient cost since 1998: variation across metropolitan areas and leading clinical conditions.

    Science.gov (United States)

    Friedman, Bernard S; Wong, Herbert S; Steiner, Claudia A

    2006-03-01

    To use disaggregated data about metropolitan statistical areas (MSAs) and clinical conditions to better describe the variation in cost increases and explore some of the hypothesized influences. The study uses the state inpatient databases from the Healthcare Cost and Utilization Project, containing all discharges from hospitals in 172 MSAs in 1998 and 2001. The discharge summary information was combined with standardized hospital accounting files, surveys of managed care plans, MSA demographics, and state data pertaining to caps on medical malpractice awards. The analysis used descriptive comparisons and multivariate regressions of admission rate and cost per case in 9 leading disease categories across the MSAs. The increase in hospital input prices and changes in severity of illness were controlled. Metropolitan statistical areas with higher HMO market penetration continued to show lower admission rates, no less so in 2001 than in 1998. A cap on malpractice awards appeared to restrain admissions, but the net effect on hospital cost per adult eroded for those states with the most experience with award caps. Higher admission rates and increase in cost were found in several disease categories.

  14. Nematodes enhance plant growth and nutrient uptake under C and N-rich conditions

    Science.gov (United States)

    Gebremikael, Mesfin T.; Steel, Hanne; Buchan, David; Bert, Wim; de Neve, Stefaan

    2016-09-01

    The role of soil fauna in crucial ecosystem services such as nutrient cycling remains poorly quantified, mainly because of the overly reductionistic approach adopted in most experimental studies. Given that increasing nitrogen inputs in various ecosystems influence the structure and functioning of soil microbes and the activity of fauna, we aimed to quantify the role of the entire soil nematode community in nutrient mineralization in an experimental set-up emulating nutrient-rich field conditions and accounting for crucial interactions amongst the soil microbial communities and plants. To this end, we reconstructed a complex soil foodweb in mesocosms that comprised largely undisturbed native microflora and the entire nematode community added into defaunated soil, planted with Lolium perenne as a model plant, and amended with fresh grass-clover residues. We determined N and P availability and plant uptake, plant biomass and abundance and structure of the microbial and nematode communities during a three-month incubation. The presence of nematodes significantly increased plant biomass production (+9%), net N (+25%) and net P (+23%) availability compared to their absence, demonstrating that nematodes link below- and above-ground processes, primarily through increasing nutrient availability. The experimental set-up presented allows to realistically quantify the crucial ecosystem services provided by the soil biota.

  15. Growth, chamber building rate and reproduction time of Palaeonummulites venosus under natural conditions.

    Science.gov (United States)

    Kinoshita, Shunichi; Eder, Wolfgang; Wöger, Julia; Hohenegger, Johann; Briguglio, Antonino

    2017-04-01

    Investigations on Palaeonummulites venosus using the natural laboratory approach for determining chamber building rate, test diameter increase rate, reproduction time and longevity is based on the decomposition of monthly obtained frequency distributions based on chamber number and test diameter into normal-distributed components. The shift of the component parameters 'mean' and 'standard deviation' during the investigation period of 15 months was used to calculate Michaelis-Menten functions applied to estimate the averaged chamber building rate and diameter increase rate under natural conditions. The individual dates of birth were estimated using the inverse averaged chamber building rate and the inverse diameter increase rate fitted by the individual chamber number or the individual test diameter at the sampling date. Distributions of frequencies and densities (i.e. frequency divided by sediment weight) based on chamber building rate and diameter increase rate resulted both in a continuous reproduction through the year with two peaks, the stronger in May /June determined as the beginning of the summer generation (generation1) and the weaker in November determined as the beginning of the winter generation (generation 2). This reproduction scheme explains the existence of small and large specimens in the same sample. Longevity, calculated as the maximum difference in days between the individual's birth date and the sampling date seems to be round about one year, obtained by both estimations based on the chamber building rate and the diameter increase rate.

  16. Petunia × hybrida floral scent production is negatively affected by high-temperature growth conditions.

    Science.gov (United States)

    Cna'ani, Alon; Mühlemann, Joelle K; Ravid, Jasmin; Masci, Tania; Klempien, Antje; Nguyen, Thuong T H; Dudareva, Natalia; Pichersky, Eran; Vainstein, Alexander

    2015-07-01

    Increasing temperatures due to changing global climate are interfering with plant-pollinator mutualism, an interaction facilitated mainly by floral colour and scent. Gas chromatography-mass spectroscopy analyses revealed that increasing ambient temperature leads to a decrease in phenylpropanoid-based floral scent production in two Petunia × hybrida varieties, P720 and Blue Spark, acclimated at 22/16 or 28/22 °C (day/night). This decrease could be attributed to down-regulation of scent-related structural gene expression from both phenylpropanoid and shikimate pathways, and up-regulation of a negative regulator of scent production, emission of benzenoids V (EOBV). To test whether the negative effect of increased temperature on scent production can be reduced in flowers with enhanced metabolic flow in the phenylpropanoid pathway, we analysed floral volatile production by transgenic 'Blue Spark' plants overexpressing CaMV 35S-driven Arabidopsis thaliana production of anthocyanin pigments 1 (PAP1) under elevated versus standard temperature conditions. Flowers of 35S:PAP1 transgenic plants produced the same or even higher levels of volatiles when exposed to a long-term high-temperature regime. This phenotype was also evident when analysing relevant gene expression as inferred from sequencing the transcriptome of 35S:PAP1 transgenic flowers under the two temperature regimes. Thus, up-regulation of transcription might negate the adverse effects of temperature on scent production. © 2014 John Wiley & Sons Ltd.

  17. Effect of fermentation conditions on lipase production by Candida utilis

    Directory of Open Access Journals (Sweden)

    SANJA Z. GRBAVCIC

    2007-08-01

    Full Text Available A wild yeast strain isolated from spoiled soybean oil and identified as Candida utilis initially presented rather low lipase activity (approximately 4 IU dm-3 in submerged culture in a universal yeast medium containing 2 % malt extract. Stu­dies were undertaken to improve the lipase production. The best yields of lipase were obtained with a medium supplemented with caprylic and oleic acids as indu­cers, but higher concentrations of the former (> 0.5 % had a negative effect on the lipase production and cell growth. The type of nitrogen source seemed also to be very important. The highest lipolytic activity of 284 IU dm-3 was achieved after 5 days of fermentation in a medium containing oleic acid and hydrolyzed casein as carbon and nitrogen sources, respectively, and supplemented with Tween 80®. It was shown that optimization of the fermentation conditions can lead to a significant improvement in the lipase production (more than 70-fold higher compared to the initial value obtained in the non-optimized medium.

  18. Fecundity, growth, and survival of the angelfish Pterophyllum scalare (Perciformes: Cichlidae under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Armando A Ortega-Salas

    2009-09-01

    Full Text Available The freshwater angelfishes (Pterophyllum are South American cichlids that have become very popular among aquarists, yet scarce information on their culture and aquarium husbandry exists. We studied Pterophyllum scalare to analyze dietary effects on fecundity, growth, and survival of eggs and larvae during 135 days. Three diets were used: A decapsulated cysts of Artemia, B commercial dry fish food, and C a mix diet of the rotifer Brachionus plicatilis and the cladoceran Daphnia magna. The initial larval density was 100 organisms in each 40L aquarium. With diet A, larvae reached a maximum weight of 3.80g, a total length of 6.3 cm, and a height of 5.8cm; with diet B: 2.80g, 4.81cm, and 4.79cm, and with diet C: 3.00g, 5.15cm, and 5.10cm, respectively. Significant differences were observed between diet A, and diet B and C, but no significantly differences were observed between diets B and C. Fecundity varied from 234 to 1 082 eggs in 20 and 50g females, respectively. Egg survival ranged from 87.4% up to 100%, and larvae survival (80 larvae/40L aquarium from 50% to 66.3% using diet B and A, respectively. Live food was better for growing fish than the commercial balanced food diet. Fecundity and survival are important factors in planning a good production of angelfish. Rev. Biol. Trop. 57 (3: 741-747. Epub 2009 September 30.Se realizaron estudios de cultivo en laboratorio del pez ángel, Pterophyllum scalare, para analizar los efectos de su dieta en la fecundidad, crecimiento y sobrevivencia en huevos y larvas por un período 135 días. Tres dietas diferentes se utilizaron A quistes decapsulados de Artemia, B comida comercial seca para pez, C una mezcla de rotíferos, Brachionus plicatilis y el cladocero, Daphnia magna. La densidad inicial de larvas en acuarios de 40L fue de 100 organismos. Utilizando la dieta A, las larvas alcanzaron un peso máximo de 3.80g, una longitud total de 6.3cm y una altura de 5.8cm; utilizando la dieta B, fue de 2.80g, 4

  19. Growth of sugarcane under high input conditions in tropical Australia. 1. Radiation use, biomass accumulation and partitioning

    International Nuclear Information System (INIS)

    Robertson, M.J.; Wood, A.W.; Muchow, R.C.

    1996-01-01

    There is little detailed information on yield accumulation in sugarcane under high-input conditions, which can be used to quantify the key physiological parameters contributing to yield variation. Sugarcane is grown under plant and ratoon crop conditions. This study analysed canopy development, radiation interception and biomass accumulation of two contrasting cultivars of sugarcane under irrigation during the same season under plant and ratoon crop conditions. Over the 15 month season, 11 crop samplings were conducted. Biomass partitioning to stalk was also measured to determine to what extent differences in partitioning between cultivars under ratoon and plant crop conditions contribute to differential productivity. The key findings were: (1) The ratoon crop accumulated biomass more quickly than the plant crop during the first 100 days of growth due to higher stalk number, faster canopy development and greater radiation interception. For similar reasons, cultivar Q138 had higher early biomass production than cultivar Q117 in the plant crop, (2) Early differences in biomass accumulation due to crop class became negligible at about 220 days because maximum RUE of the plant crop (1.72 +/- 0.01 g MJ -1 ) was 8% higher than in the first ratoon crop (1.59 +/- 0.08 g MJ -1 ). The higher maximum RUE in the plant crop was consistent with a higher crop growth rate (35.1 +/- 2.3 versus 31.0 +/- 3.4 g m -2 d -1 ) during the Linear phase of biomass accumulation. (3) Biomass accumulation, which ceased about 300 days after planting/ratooning and 140 days before final harvest, attained similar levels of 53-58 t ha -1 in all four crops. (4) The plateau in biomass was associated with loss of live millable stalks, and not a cessation in the growth rate of individual stalks. The crops continued to intercept radiation while on the biomass plateau, so that average RUEs at final harvest were much lower than the maximum values. (5) There was no effect of crop class or cultivar on the

  20. Correlation of Growth and Surface Properties of Poly(\\(p\\-xylylenes to  Reaction Conditions

    Directory of Open Access Journals (Sweden)

    Andreas Reichel

    2015-05-01

    Full Text Available Parylene, a non-critical, non-toxic layer material, which is not only a candidate for low-\\(K\\ dielectrics, but also well suited for long-term applications in the human body, has been deposited by (plasma-enhanced chemical vapor deposition of the monomeric species. To that end, a specially-designed reactor exhibiting a cracker tube at its entrance, which serves as the upstream control, and a cooling trap in front of the downstream control has been applied. The process of polymerization has been traced and is explained by evaporating the dimeric species followed by dissociation in the cracker at elevated temperatures and, eventually, to the coating of the polymeric film in terms of thermodynamics. Alternatively, the process of dissociation has been accomplished applying a microwave plasma. In both cases, the monomerization is controlled by mass spectrometry. The window for surface polymerization could be clearly defined in terms of a factor of dilution by an inert gas for the chemical vapor deposition (CVD case and in the case of plasma-enhanced chemical vapor deposition (PECVD, additionally by the power density. The characterization of the layer parameters has been carried out by several analytical tools: scanning electron microscopy and atomic force microscopy to determine the surface roughness and density and depth of voids in the film, which influence the layer capacitance and deteriorate the breakdown voltage, a bulk property. The main issue is the conduct against liquids between the two borders' hydrophilic and hydrophobic conduct, but also the super-hydrophobic character, which is the condition for the Lotus effect. The surface tension has been evaluated by contact angle measurements. Fourier-transform infrared spectroscopy has proven the conservation of all of the functional groups during polymerization.

  1. A comparison of nitrate level in spinach grown both under different densities in aquaponic system and under natural growth conditions

    Directory of Open Access Journals (Sweden)

    Ştefan Mihai PETREA

    2013-12-01

    Full Text Available As bio-integrated systems that link both plants and fish culture, inside aquaponic systems, the processes of ammonia-oxidizing and nitrification in nitrite and nitrate are essential for growth and development of both fish and plants culture biomass. Plants with nearly the same nutritional requirements during their life cycle, like spinach in our case, are recommended to be grown under aquaponic conditions. Although nitrates concentrations up to 200 – 250mg/l are reported to be acceptable for fish growth, in the last years the toxic effect of long term exposure to high nitrate levels on fish and plants cultured biomass were highlighted. The main goal of the present study is to compare the nitrate level of spinach, grown in an aquaponic system, under three plant densities (V1 - 59 plants/m2, V2 - 48plants/m2 and V3 – 39 plants/m2. The second objective is to compare the results obtained, in term of nitrate content, for spinach grown in the integrated rainbow trout – spinach aquaponic system with those of marketable spinach, grown under conventional condition, in the field. The experimental design consists in a recirculating aquaculture system with 12 growing units, mechanical and biological water treatment units and four aquaponic units. Fish were fed with two types of feed with 41% and 50% protein, using 3 different feeding regimes. The results show a higher nitrate level on spinach grown in aquaponic system, compared to the one derived from field culture. Differences were observed also among the three variants grown in aquaponic conditions, under different plant densities. As a conclusion, it can be said that considering the nitrate level, spinach grown in aquaponic system is marketable.

  2. Conditional expression of CD44 isoforms in lymphoma cells: influence on hyaluronate binding and tumor growth

    Energy Technology Data Exchange (ETDEWEB)

    Fu, J.

    2002-03-01

    CD44 describes a family of surface proteins consisting of many isoforms due to alternative splice of ten 'variant' exons. Members of this family are involved in various processes including hematopoiesis, lymphocyte activation and homing, limb development, wound healing and tumor progression. Clinically, CD44 has been shown to be a prognostic factor for several human cancers. To answer the question which isoform might be relevant for tumor progression and to gain an insight into the mechanism of its function, I established transfectants of the LB lymphoma cell line in which the expression of four CD44 isoforms, namely CD44v3-10, CD44v4-10, CD44v8-10 and CD44s, was controlled by the Tet-off promoter. In the presence of Doxycycline, the expression was repressed. Removal of Doxycycline switched on expression and the maximal CD44 amount was obtained within two days. The transfectants were characterized regarding their ability to bind to the extracellular matrix component hyaluronate (HA). Overexpression of all four CD44 isoforms conferred the ability to bind HA on LB cells. Other glycosaminoglycans (GAGs) were bound in an isotype-specific fashion. CD44v3-10, CD44v4-10 and CD44v8-10 showed high binding affinity to chondroitin A, B and C, and low affinity to heparin, heparan sulfate and keratan sulfate. CD44s could not bind to these GAGs. Among these three variants, the binding ability of CD44v3-10 was the strongest. CD44 clustering seemed to play a crucial role for HA binding. Both CD44s and CD44v8-10 formed reduction-sensitive complexes in LB cells. The complexes are homooligomers or heterooligomers composed of different isoforms. Cys286 in CD44 transmember domain was not responsible for the formation of reduction-sensitive oligomer or for the enhanced HA binding in LB cell line. Using a conditional dimerization system the requirement of CD44 oligomerization for HA binding was directly demonstrated. The induction of oligomerization increased HA binding

  3. Conditional expression of CD44 isoforms in lymphoma cells: influence on hyaluronate binding and tumor growth

    International Nuclear Information System (INIS)

    Fu, J.

    2002-03-01

    CD44 describes a family of surface proteins consisting of many isoforms due to alternative splice of ten 'variant' exons. Members of this family are involved in various processes including hematopoiesis, lymphocyte activation and homing, limb development, wound healing and tumor progression. Clinically, CD44 has been shown to be a prognostic factor for several human cancers. To answer the question which isoform might be relevant for tumor progression and to gain an insight into the mechanism of its function, I established transfectants of the LB lymphoma cell line in which the expression of four CD44 isoforms, namely CD44v3-10, CD44v4-10, CD44v8-10 and CD44s, was controlled by the Tet-off promoter. In the presence of Doxycycline, the expression was repressed. Removal of Doxycycline switched on expression and the maximal CD44 amount was obtained within two days. The transfectants were characterized regarding their ability to bind to the extracellular matrix component hyaluronate (HA). Overexpression of all four CD44 isoforms conferred the ability to bind HA on LB cells. Other glycosaminoglycans (GAGs) were bound in an isotype-specific fashion. CD44v3-10, CD44v4-10 and CD44v8-10 showed high binding affinity to chondroitin A, B and C, and low affinity to heparin, heparan sulfate and keratan sulfate. CD44s could not bind to these GAGs. Among these three variants, the binding ability of CD44v3-10 was the strongest. CD44 clustering seemed to play a crucial role for HA binding. Both CD44s and CD44v8-10 formed reduction-sensitive complexes in LB cells. The complexes are homooligomers or heterooligomers composed of different isoforms. Cys286 in CD44 transmember domain was not responsible for the formation of reduction-sensitive oligomer or for the enhanced HA binding in LB cell line. Using a conditional dimerization system the requirement of CD44 oligomerization for HA binding was directly demonstrated. The induction of oligomerization increased HA binding. Finally, I

  4. Insulin-like growth factor-I, insulin-like growth factor binding protein-3 and the risk of fibrocystic breast conditions among Chinese women.

    Science.gov (United States)

    Chen, Chu; Doherty, Jennifer A; Lewis, S Kay; Ray, Roberta M; Gao, Dao Li; Stalsberg, Helge; Feng, Ziding; Thomas, David B

    2006-05-01

    We investigated whether circulating insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) levels are associated with the risk of fibrocystic breast conditions (FBC), in a case-control study nested within a randomized trial of breast self-examination conducted in Shanghai, China. Participants were enrolled during 1989-1991 and were followed over 10 years for the development of breast diseases. Controls (n = 897) were frequency-matched by age to cases (n = 451), who were diagnosed with FBC between 1995 and 2000. Circulating IGF-I and IGFBP-3 levels and their molar ratio were positively associated with risk of FBC. The odds ratios (ORs) and 95% confidence intervals (CI) for the upper fourth of the distribution compared to the lowest fourth for IGF-I, IGFBP3 and their molar ratio were 3.02 (2.02-4.52), 1.92 (1.37-2.71) and 2.26 (1.52-3.36), respectively. The strength of the association between IGF-I levels and FBC was attenuated after adjustment for IGFBP-3 and that for IGFBP-3 was largely eliminated after adjustment for IGF-I. Increasing levels of IGF-I were particularly associated with increasing risk of FBC with proliferative elements (ORs and 95% CIs for the 2nd, 3rd and upper fourth of the distribution of IGF-I: 3.13 (1.50-6.53), 4.57 (2.22-9.39) and 6.30 (3.08-12.89), compared with the lowest fourth. Our results suggest that elevated levels of IGF-I may contribute to the development of FBC. 2005 Wiley-Liss, Inc.

  5. The effect of Nitrogen on Radiation Use Efficiency and Growth indices of Maize Hybrids (Zea mays L. under Kermanshah Condition

    Directory of Open Access Journals (Sweden)

    M Ahmadi

    2018-02-01

    Full Text Available Introduction Dry matter produced by crops is a function of absorbed radiation and radiation use efficiency. Radiation use efficiency is an effective approach to quantify total dry matter accumulation. It is defined as biomass produced by plant for solar radiation absorbed during growing season. Radiation use efficiency is often calculated from the linear regression slope between total dry matter accumulation and cumulative solar radiation absorbed. It is affected by species, weather conditions, crop management, plant development stages, and the production of photosynthesis compounds. Among the factors of agronomic management, nitrogen fertilizer and crop species are the most important aspects that affect the radiation use efficiency. Therefore, by considering the fact that Kermanshah province has favorable condition in terms of more natural resources such as solar radiation, the aims of the present study were evaluation of nitrogen effect on radiation use efficiency, growth indices and yield of some current maize hybrids. Materials and Methods A split plot experiment was done based on randomized complete block design with 4 replications at 2014. Treatments were 4 levels of nitrogen fertilizer application (40%, 70%, 100% and 140% of the maize demand to nitrogen which based on the amount recommended by soil experiment equivalent to 138, 238, 350 and 483 kg.ha-1 of urea as main plots and 3 maize hybrids KSC-704, BC-678 and Simon as sub plots. Leaf area index and total dry matter yield measured during growing season. Crop growth rate and relative growth ratio calculated by differentiation from fitted equation on total dry matter yield data. In order to calculate radiation use efficiency, sunny hours for Kermanshah latitude obtained from the nearest weather station. Daily solar radiation simulated by the method cited by Goudriaan and Van Laar (1993 for growing season. The absorbed radiation in each stage obtained through the multiplication simulated

  6. Effect of silicon application on physiological characteristics and growth of wheat (Triticum aestivum L. under drought stress condition

    Directory of Open Access Journals (Sweden)

    A. Karmollachaab

    2016-05-01

    Full Text Available In order to investigate the effect of silicon application on some physiological characteristics and growth of Wheat (Triticum aestivum L. under late drought stress condition, an experiment was conducted at the Agriculture and Natural Resources University of Ramin, Khuzestan during year 2012. The experiment was conducted in the open environment as factorial randomized complete block design with three levels of drought stress (irrigation after 25, 50 and 75% depletion of available water content as the first factor and four levels of silicon (0, 10, 20 and 30 mg Si.kg-1 soil as the second factor with three replications. The results showed that drought stress imposed a negative significant effect on all traits. The drought stress led to increased electrolyte leakage and proline content, cuticular wax, leaf silicon concentration, superoxide dismutase activity (SOD and grain potassium were decreased. The severe drought stress has most effect on electrolyte leakage (up to 53%. The application of silicon except the shoot/root parameter, on all characters have been affected so that application of 30 mg Si.kg-1 soil led to decrease electrolyte leakage up to 22.5% and increased SOD activity, proline content, cuticular wax grain K and flag leaf Si concentration, 25, 12.8, 21, 17 and 30% compared to control, respectively. In general, the results showed a positive effect of silicon on wheat plant under stress conditions that were higher than no stress condition.

  7. Conditional inactivation of TNFα-converting enzyme in chondrocytes results in an elongated growth plate and shorter long bones.

    Directory of Open Access Journals (Sweden)

    Kenta Saito

    Full Text Available TNFα-converting enzyme (TACE is a membrane-bound proteolytic enzyme with essential roles in the functional regulation of TNFα and epidermal growth factor receptor (EGFR ligands. Previous studies have demonstrated critical roles for TACE in vivo, including epidermal development, immune response, and pathological neoangiogenesis, among others. However, the potential contribution of TACE to skeletal development is still unclear. In the present study, we generated a Tace mutant mouse in which Tace is conditionally disrupted in chondrocytes under the control of the Col2a1 promoter. These mutant mice were fertile and viable but all exhibited long bones that were approximately 10% shorter compared to those of wild-type animals. Histological analyses revealed that Tace mutant mice exhibited a longer hypertrophic zone in the growth plate, and there were fewer osteoclasts at the chondro-osseous junction in the Tace mutant mice than in their wild-type littermates. Of note, we found an increase in osteoprotegerin transcripts and a reduction in Rankl and Mmp-13 transcripts in the TACE-deficient cartilage, indicating that dysregulation of these genes is causally related to the skeletal defects in the Tace mutant mice. Furthermore, we also found that phosphorylation of EGFR was significantly reduced in the cartilage tissue lacking TACE, and that suppression of EGFR signaling increases osteoprotegerin transcripts and reduces Rankl and Mmp-13 transcripts in primary chondrocytes. In accordance, chondrocyte-specific abrogation of Egfr in vivo resulted in skeletal defects nearly identical to those observed in the Tace mutant mice. Taken together, these data suggest that TACE-EGFR signaling in chondrocytes is involved in the turnover of the growth plate during postnatal development via the transcriptional regulation of osteoprotegerin, Rankl, and Mmp-13.

  8. Crystal Growth in Al72.9Ge27.1 Alloy Melt under Acoustic Levitation Conditions

    International Nuclear Information System (INIS)

    Yan Na; Dai Fu-Ping; Wang Wei-Li; Wei Bing-Bo

    2011-01-01

    The nonequilibrium solidification of liquid Al 72.9 Ge 27.1 hypoeutectic alloy is accomplished by using single-axis acoustic levitation. A maximum undercooling of 112K (0.16T L ) is obtained for the alloy melt at a cooling rate of 50 K/s. The primary (Al) phase displays a morphological transition from coarse dendrite under a normal conditions to equiaxed grain under acoustic levitation. In the (Al)+(Ge) eutectic, the (Ge) phase exhibits a conspicuous branched growth morphology. Both the primary (Al) dendrites and (Al)+(Ge) eutectics are well refined and the solute content of the primary (Al) phase is extended under acoustic levitation. The calculated and experimental results indicate that the solute trapping effect becomes more intensive with the enhancement of bulk undercooling. (cross-disciplinary physics and related areas of science and technology)

  9. Baseline growth and reproductive parameters in Lymnaea stagnalis for OECD test guideline development: optimization of diets and culturing conditions

    DEFF Research Database (Denmark)

    Holbech, Henrik; Hutchinson, Tom

    laboratories in Denmark, Germany and the UK for the OECD pre-validation work to date. Laboratory cultures of L. stagnalis are traditionally fed fresh (preferably organic) lettuce; however, interrupted supplies of fresh lettuce in some countries in 2011 highlighted a potential problem for the draft OECD test...... of a mollusc reproduction test guideline. An ad hoc mollusc expert group has been formed in Europe to validate methods that can meet this need. Currently, a key species for use in this context is the freshwater gastropod Lymnaea stagnalis. An important aspect of this work is to first develop a specific...... pathogen free defined strain of L. stagnalis and second to establish a historical database of growth and reproductive rates under defined culturing conditions. A mass culture of the RENILYS® strain of L. stagnalis have been established at INRA (France) since 2002 and has been distributed to research...

  10. Transforming growth factor β family members in regulation of vascular function: in the light of vascular conditional knockouts.

    Science.gov (United States)

    Jakobsson, Lars; van Meeteren, Laurens A

    2013-05-15

    Blood vessels are composed of endothelial cells, mural cells (smooth muscle cells and pericytes) and their shared basement membrane. During embryonic development a multitude of signaling components orchestrate the formation of new vessels. The process is highly dependent on correct dosage, spacing and timing of these signaling molecules. As vessels mature some cascades remain active, albeit at very low levels, and may be reactivated upon demand. Members of the Transforming growth factor β (TGF-β) protein family are strongly engaged in developmental angiogenesis but are also regulators of vascular integrity in the adult. In humans various genetic alterations within this protein family cause vascular disorders, involving disintegration of vascular integrity. Here we summarize and discuss recent data gathered from conditional and endothelial cell specific genetic loss-of-function of members of the TGF-β family in the mouse. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Nucleation and growth process of sodalite and cancrinite from kaolinite-rich clay under low-temperature hydrothermal conditions

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Ríos Reyes

    2013-04-01

    Full Text Available The synthesis of low-silica zeotypes by hydrothermal transformation of kaolinite-rich clay and the nucleation and growth processes of sodalite and cancrinite in the system Na2O-Al2O3-SiO2-H2O at 100 °C were investigated. The synthesis products were characterized by X-ray powder diffraction (XRPD, scanning electron microscopy (SEM, Fourier transform infrared spectroscopy (FT-IR, 29Si and 27Al Magic Angle Spinning Nuclear Magnetic Resonance (MAS-NMR and thermogravimetric analysis (TGA. Our data show that the sequence of the transformation of phases is: Poorly crystalline aluminosilicate → zeolite LTA → sodalite → sodalite + cancrinite → cancrinite. Synthesized materials appeared stable thermodynamically under the experimental conditions, with zeolite LTA (a metastable phase occurring as a minor phase, compared with the presence of sodalite and cancrinite.

  12. Influence of abscisic acid on growth, biomass and lipid yield of Scenedesmus quadricauda under nitrogen starved condition.

    Science.gov (United States)

    Sulochana, Sujitha Balakrishnan; Arumugam, Muthu

    2016-08-01

    Scenedesmus quadricauda, accumulated more lipid but with a drastic reduction in biomass yield during nitrogen starvation. Abscisic acid (ABA) being a stress responsible hormone, its effect on growth and biomass with sustainable lipid yield during nitrogen depletion was studied. The result revealed that the ABA level shoots up at 24h (27.21pmol/L) during the onset of nitrogen starvation followed by a sharp decline. The external supplemented ABA showed a positive effect on growth pattern (38×10(6)cells/ml) at a lower concentration. The dry biomass yield is also increasing up to 2.1 fold compared to nitrogen deficient S. quadricauda. The lipid content sustains in 1 and 2μM concentration of ABA under nitrogen-deficient condition. The fatty acid composition of ABA treated S. quadricauda cultures with respect to nitrogen-starved cells showed 11.17% increment in saturated fatty acid content, the desired lipid composition for biofuel application. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. In planta engineering of gold nanoparticles of desirable geometries by modulating growth conditions: an environment-friendly approach.

    Science.gov (United States)

    Starnes, Daniel L; Jain, Ajay; Sahi, Shivendra V

    2010-09-15

    Unique properties of gold nanoparticles (AuNPs) can be achieved by manipulating their geometries. However, it is not known if the shapes and sizes of AuNPs can be modulated in planta. Here, we evaluated the accumulation of gold across taxonomically diverse plant species (alfalfa, cucumber, red clover, ryegrass, sunflower, and oregano). Significant variations were detected in the uptake of gold in the roots ranging from 500 ppm (ryegrass) to 2500 ppm (alfalfa). Alfalfa was selected for subsequent studies due to its ability to accumulate relatively large quantities of gold in its roots. Temporal analysis revealed that most of the AuNPs formed within 6 h of treatment, and the majority of them fall within the size range of 10-30 nm. Spherical AuNPs (1-50 nm) were detected ubiquitously across different treatments. To elucidate the effects of growth variables on the geometries of in planta synthesized AuNPs, alfalfa was subjected to KAuCl(4) (50 ppm) treatment for 3d under different pH, temperature, and light regimes. Interestingly, manipulation of growth conditions triggered a noticeable shift in the relative abundance of spherical, triangular, hexagonal, and rectangular AuNPs providing empirical evidence toward the feasibility of their in planta engineering.

  14. Optimization of conditions for growth of vanadium dioxide thin films on silicon by pulsed-laser deposition

    Science.gov (United States)

    Shibuya, Keisuke; Sawa, Akihito

    2015-10-01

    We systematically examined the effects of the substrate temperature (TS) and the oxygen pressure (PO2) on the structural and optical properties polycrystalline V O2 films grown directly on Si(100) substrates by pulsed-laser deposition. A rutile-type V O2 phase was formed at a TS ≥ 450 °C at PO2 values ranging from 5 to 20 mTorr, whereas other structures of vanadium oxides were stabilized at lower temperatures or higher oxygen pressures. The surface roughness of the V O2 films significantly increased at growth temperatures of 550 °C or more due to agglomeration of V O2 on the surface of the silicon substrate. An apparent change in the refractive index across the metal-insulator transition (MIT) temperature was observed in V O2 films grown at a TS of 450 °C or more. The difference in the refractive index at a wavelength of 1550 nm above and below the MIT temperature was influenced by both the TS and PO2, and was maximal for a V O2 film grown at 450 °C under 20 mTorr. Based on the results, we derived the PO2 versus 1/TS phase diagram for the films of vanadium oxides, which will provide a guide to optimizing the conditions for growth of V O2 films on silicon platforms.

  15. Optimization of conditions for growth of vanadium dioxide thin films on silicon by pulsed-laser deposition

    Directory of Open Access Journals (Sweden)

    Keisuke Shibuya

    2015-10-01

    Full Text Available We systematically examined the effects of the substrate temperature (TS and the oxygen pressure (PO2 on the structural and optical properties polycrystalline V O2 films grown directly on Si(100 substrates by pulsed-laser deposition. A rutile-type V O2 phase was formed at a TS ≥ 450 °C at PO2 values ranging from 5 to 20 mTorr, whereas other structures of vanadium oxides were stabilized at lower temperatures or higher oxygen pressures. The surface roughness of the V O2 films significantly increased at growth temperatures of 550 °C or more due to agglomeration of V O2 on the surface of the silicon substrate. An apparent change in the refractive index across the metal–insulator transition (MIT temperature was observed in V O2 films grown at a TS of 450 °C or more. The difference in the refractive index at a wavelength of 1550 nm above and below the MIT temperature was influenced by both the TS and PO2, and was maximal for a V O2 film grown at 450 °C under 20 mTorr. Based on the results, we derived the PO2 versus 1/TS phase diagram for the films of vanadium oxides, which will provide a guide to optimizing the conditions for growth of V O2 films on silicon platforms.

  16. Characterization of plant-growth promoting diazotrophic bacteria isolated from field grown Chinese cabbage under different fertilization conditions.

    Science.gov (United States)

    Yim, Woo-Jong; Poonguzhali, Selvaraj; Madhaiyan, Munusamy; Palaniappan, Pitchai; Siddikee, M A; Sa, Tongmin

    2009-04-01

    Diazotrophic bacteria isolated from the rhizosphere of Chinese cabbage were assessed for other plant growth promoting characteristics viz., production of IAA, ethylene, ACC deaminase, phosphate solubilization, and gnotobiotic root elongation. Their effect on inoculation to Chinese cabbage was also observed under growth chamber conditions. A total of 19 strains that showed higher nitrogenase activity identified by 16S rRNA gene sequence analysis were found to be the members of the genera Pseudomonas and Agrobacterium belonging to alpha- and gamma-Proteobacteria groups. These strains were also efficient in producing IAA and ACC deaminase though they produced low levels of ethylene and no phosphate solubilization. In addition, inoculation of selected diazotrophic bacterial strains significantly increased seedling length, dry weight, and total nitrogen when compared to uninoculated control. The colonization of crop plants by diazotrophic bacteria can be affected by many biotic and abiotic factors, and further studies are oriented towards investigating the factors that could influence the establishment of a selected bacterial community.

  17. Conidial germination in Scedosporium apiospermum, S. aurantiacum, S. minutisporum and Lomentospora prolificans: influence of growth conditions and antifungal susceptibility profiles

    Directory of Open Access Journals (Sweden)

    Thaís Pereira de Mello

    2016-01-01

    Full Text Available In the present study, we have investigated some growth conditions capable of inducing the conidial germination in Scedosporium apiospermum, S. aurantiacum, S. minutisporum and Lomentospora prolificans. Germination in Sabouraud medium (pH 7.0, 37ºC, 5% CO2 showed to be a typically time-dependent event, reaching ~75% in S. minutisporum and > 90% in S. apiospermum, S. aurantiacum and L. prolificans after 4 h. Similar germination rate was observed when conidia were incubated under different media and pHs. Contrarily, temperature and CO2 tension modulated the germination. The isotropic conidial growth (swelling and germ tube-like projection were evidenced by microscopy and cytometry. Morphometric parameters augmented in a time-dependent fashion, evidencing changes in size and granularity of fungal cells compared with dormant 0 h conidia. In parallel, a clear increase in the mitochondrial activity was measured during the transformation of conidia-into-germinated conidia. Susceptibility profiles to itraconazole, fluconazole, voriconazole, amphotericin B and caspofungin varied regarding each morphotype and each fungal species. Overall, the minimal inhibitory concentrations for hyphae were higher than conidia and germinated conidia, except for caspofungin. Collectively, our study add new data about the conidia-into-hyphae transformation in Scedosporium and Lomentospora species, which is a relevant biological process of these molds directly connected to their antifungal resistance and pathogenicity mechanisms.

  18. Cell cycle analysis of brain cells as a growth index in larval cod at different feeding conditions and temperatures

    Directory of Open Access Journals (Sweden)

    Rafael González-Quirós

    2007-09-01

    Full Text Available The percentage of cells dividing in a specific tissue of individual larvae can be estimated by analyzing DNA per cell by flow cytometry. An experimental test was carried out with cod (Gadus morhua larvae, with brain as the target tissue, to validate this technique as an appropriate growth index for larval fish. Standard length (SL, myotome height, and %S-phase (% of cells in the S-phase of the cell-division cycle variability were analyzed, with temperature (6 and 10°C, food level (high- and no-food and larval developmental stage (first feeding, pre-metamorphosis and post-metamorphosis as independent factors. Cod larvae grew faster (in SL and presented a higher %S-phase under high-food conditions. Larval SL increased with temperature in rearing and experimental tanks. However, there was a significant interaction between temperature and food in the %S-phase. There were no significant differences in the %S-phase between 6 and 10°C at high-food levels. We suggest that this result is a consequence of temperature-dependency of the duration of the cell cycle. In the absence of food, larvae at 10ºC had a lower %S-phase than larvae at 6°C, which may be related to increased metabolic costs with increasing temperature. Considering the effect of temperature, the mean % S-phase explained 74% of the variability in the estimated standard growth rate.

  19. Growth-promoting effects of a seaweed concentrate at various pH and water hardness conditions

    Directory of Open Access Journals (Sweden)

    Georgina D. Arthur

    2013-11-01

    Full Text Available Kelpak® – a liquid seaweed concentrate made from the kelp Ecklonia maxima (Osbeck Papenfuss – is used as a natural biostimulant to promote rooting and improve yield in crops. Plant–soil environmental conditions and the chemistry of water used for irrigation may affect the efficiency of Kelpak. The effect of pH (pH 4.5, 6.5 and 8.5 and water hardness (200 mg/L and 400 mg/L Ca2+ on the growth-promoting ability of Kelpak was assessed using the mungbean rooting bioassay and in a pot trial with Swiss chard. Kelpak promoted rooting in all the treatments in the mungbean bioassay with maximum rooting generally achieved with 20% Kelpak. With 20% Kelpak, the addition of 200 mg/L and 400 mg/L Ca2+ decreased rooting at pH 4.5, increased rooting at pH 6.5 and did not affect rooting at pH 8.5. A similar trend was observed in the pot trial with Swiss chard: leaf and root (fresh weight and pigment content (chl a, chl b and carotenoids improved with the addition of 200 mg/L Ca2+ + 5% Kelpak at pH 6.5 or pH 8.5, while Kelpak was able to partially mask the negative effect of 200 mg/L Ca2+ at pH 4.5. These results suggest that while Kelpak is most effective in neutral pHs, it can be used to promote plant growth in a wide range of pH and water hardness conditions.

  20. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Thomas D. [University of California, Berkeley, CA 94720 (United States); Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Lyubimov, Artem Y. [Stanford University, Stanford, CA 94305 (United States); Ogata, Craig M. [Argonne National Laboratory, Argonne, IL 60439 (United States); Vo, Huy [Johns Hopkins University, Baltimore, MD 21205 (United States); Uervirojnangkoorn, Monarin; Brunger, Axel T., E-mail: brunger@stanford.edu [Stanford University, Stanford, CA 94305 (United States); Berger, James M., E-mail: brunger@stanford.edu [Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); University of California, Berkeley, CA 94720 (United States)

    2015-09-26

    A highly X-ray-transparent, silicon nitride-based device has been designed and fabricated to harvest protein microcrystals for high-resolution X-ray diffraction data collection using microfocus beamlines and XFELs. Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs.

  1. Growth and Yield Responses of Green Pepper (Capsicum annum L. to Manure Rates under Field and High Tunnel Conditions

    Directory of Open Access Journals (Sweden)

    Ima-obong I. DOMINIC

    2017-03-01

    Full Text Available The present study was conducted to determine growth and yield responses of green pepper to varying manure rates under field and high tunnel conditions. Experiment 1 was a pot experiment to evaluate three rates (0.5 and 10 t/ha of poultry manure (PM on green pepper production under high tunnel and open field conditions. Experiment 2 was to determine the performance of green pepper as influenced by different manure rates (0, 5 and 10 t/ha of PM, 300 kg/ha of NPK, 5 t/ha of PM + 200 kg of NPK and 10 t/ha of PM + 100 kg of NPK on the field. High tunnel produced about 3.1 fruits/plant that weighted 102.8 g, which was significantly higher than open field experiment in which 1.7 fruits/plant, with a medium weight of 32.3 g were noted. High tunnel enhanced successful production of green pepper during rainy season, whereas the open field production during the same season was near failure. Application of 10 t/ha of PM produced significantly larger fruits in the pot experiment. Good fertilizer effects on growth and yield components were recorded for the field study. Plant height, number of leaves and branches, number and weight of harvested fruit followed similar trend in 5 and 10 t/ha of PM which gave statistically similar results, and provided the best performance during the experiment. Application of 5 t/ha of PM produced the highest total fruits yield.

  2. A high-transparency, micro-patternable chip for X-ray diffraction analysis of microcrystals under native growth conditions

    International Nuclear Information System (INIS)

    Murray, Thomas D.; Lyubimov, Artem Y.; Ogata, Craig M.; Vo, Huy; Uervirojnangkoorn, Monarin; Brunger, Axel T.; Berger, James M.

    2015-01-01

    A highly X-ray-transparent, silicon nitride-based device has been designed and fabricated to harvest protein microcrystals for high-resolution X-ray diffraction data collection using microfocus beamlines and XFELs. Microcrystals present a significant impediment to the determination of macromolecular structures by X-ray diffraction methods. Although microfocus synchrotron beamlines and X-ray free-electron lasers (XFELs) can enable the collection of interpretable diffraction data from microcrystals, there is a need for efficient methods of harvesting small volumes (<2 µl) of microcrystals grown under common laboratory formats and delivering them to an X-ray beam source under native growth conditions. One approach that shows promise in overcoming the challenges intrinsic to microcrystal analysis is to pair so-called ‘fixed-target’ sample-delivery devices with microbeam-based X-ray diffraction methods. However, to record weak diffraction patterns it is necessary to fabricate devices from X-ray-transparent materials that minimize background scattering. Presented here is the design of a new micro-diffraction device consisting of three layers fabricated from silicon nitride, photoresist and polyimide film. The chip features low X-ray scattering and X-ray absorption properties, and uses a customizable blend of hydrophobic and hydrophilic surface patterns to help localize microcrystals to defined regions. Microcrystals in their native growth conditions can be loaded into the chips with a standard pipette, allowing data collection at room temperature. Diffraction data collected from hen egg-white lysozyme microcrystals (10–15 µm) loaded into the chips yielded a complete, high-resolution (<1.6 Å) data set sufficient to determine a high-quality structure by molecular replacement. The features of the chip allow the rapid and user-friendly analysis of microcrystals grown under virtually any laboratory format at microfocus synchrotron beamlines and XFELs

  3. MODEL-ASSISTED ESTIMATION OF THE GENETIC VARIABILITY IN PHYSIOLOGICAL PARAMETERS RELATED TO TOMATO FRUIT GROWTH UNDER CONTRASTED WATER CONDITIONS

    Directory of Open Access Journals (Sweden)

    Dario Constantinescu

    2016-12-01

    Full Text Available Drought stress is a major abiotic stres threatening plant and crop productivity. In case of fleshy fruits, understanding Drought stress is a major abiotic stress threatening plant and crop productivity. In case of fleshy fruits, understanding mechanisms governing water and carbon accumulations and identifying genes, QTLs and phenotypes, that will enable trade-offs between fruit growth and quality under Water Deficit (WD condition is a crucial challenge for breeders and growers. In the present work, 117 recombinant inbred lines of a population of Solanum lycopersicum were phenotyped under control and WD conditions. Plant water status, fruit growth and composition were measured and data were used to calibrate a process-based model describing water and carbon fluxes in a growing fruit as a function of plant and environment. Eight genotype-dependent model parameters were estimated using a multiobjective evolutionary algorithm in order to minimize the prediction errors of fruit dry and fresh mass throughout fruit development. WD increased the fruit dry matter content (up to 85 % and decreased its fresh weight (up to 60 %, big fruit size genotypes being the most sensitive. The mean normalized root mean squared errors of the predictions ranged between 16-18 % in the population. Variability in model genotypic parameters allowed us to explore diverse genetic strategies in response to WD. An interesting group of genotypes could be discriminated in which i the low loss of fresh mass under WD was associated with high active uptake of sugars and low value of the maximum cell wall extensibility, and ii the high dry matter content in control treatment (C was associated with a slow decrease of mass flow. Using 501 SNP markers genotyped across the genome, a QTL analysis of model parameters allowed to detect three main QTLs related to xylem and phloem conductivities, on chromosomes 2, 4 and 8. The model was then applied to design ideotypes with high dry matter

  4. Effects of dietary exposure to brominated flame retardant BDE-47 on thyroid condition, gonadal development and growth of zebrafish

    Science.gov (United States)

    Torres, Leticia; Orazio, Carl E.; Peterman, Paul H.; Patino, Reynaldo

    2013-01-01

    Little is known about the effects of brominated flame retardants in teleosts and some of the information currently available is inconsistent. This study examined effects of dietary exposure to 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) on thyroid condition, body mass and size, and gonadal development of zebrafish. Pubertal, 49-day-old (posthatch) fish were fed diets without BDE-47 (control) or with 1, 5 or 25 μg/g BDE-47/diet. Treatments were conducted in triplicate 30-L tanks each containing 50 zebrafish, and 15 fish per treatment (5 per tank) were sampled at days 40, 80 and 120 of exposure. Measurements were taken of body mass, standard length, head depth and head length. Sex (at 40–120 days of exposure), germ cell stage (at 40 days) and thyroid condition (at 120 days; follicular cell height, colloid depletion, angiogenesis) were histologically determined. Whole-body BDE-47 levels at study completion were within the high end of levels reported in environmentally exposed (wild) fishes. Analysis of variance was used to determine differences among treatments at each sampling time. No effects were observed on thyroid condition or germ cell stage in either sex. Reduced head length was observed in females exposed to BDE-47 at 80 days but not at 40 or 120 days. In males, no apparent effects of BDE-47 were observed at 40 and 80 days, but fish exposed to 25 μg/g had lower body mass at 120 days compared to control fish. These observations suggest that BDE-47 at environmentally relevant whole-body concentrations does not affect thyroid condition or pubertal development of zebrafish but does affect growth during the juvenile-to-adult transition, especially in males.

  5. Cytotoxic Potential of Bacillus cereus Strains ATCC 11778 and 14579 Against Human Lung Epithelial Cells Under Microaerobic Growth Conditions

    Directory of Open Access Journals (Sweden)

    Kathleen eKilcullen

    2016-02-01

    Full Text Available Bacillus cereus, a food poisoning bacterium closely related to Bacillus anthracis, secretes a multitude of virulence factors including enterotoxins, hemolysins, and phospholipases. However, the majority of the in vitro experiments evaluating the cytotoxic potential of B. cereus were carried out in the conditions of aeration, and the impact of the oxygen limitation in conditions encountered by the microbe in natural environment such as gastrointestinal tract remains poorly understood. This research reports comparative analysis of ATCC strains 11778 (BC1 and 14579 (BC2 in aerated and microaerobic (static cultures with regard to their toxicity for human lung epithelial cells. We showed that BC1 increased its toxicity upon oxygen limitation while BC2 was highly cytotoxic in both growth conditions. The combined effect of the pore-forming, cholesterol-dependent hemolysin, cereolysin O (CLO, and metabolic product(s such as succinate produced in microaerobic conditions provided substantial contribution to the toxicity of BC1 but not BC2 which relied mainly on other toxins. This mechanism is shared between CB1 and B. anthracis. It involves the permeabilization of the cell membrane which facilitates transport of toxic bacterial metabolites into the cell. The toxicity of BC1was potentiated in the presence of bovine serum albumin which appeared to serve as reservoir for bacteria-derived nitric oxide participating in the downstream production of reactive oxidizing species with the properties of peroxynitrite. In agreement with this the BC1cultures demonstrated the increased oxidation of the indicator dye Amplex Red catalyzed by peroxidase as well as the increased toxicity in the presence of externally added ascorbic acid.

  6. Growth and Tissue Elemental Composition Response of Spinach (Spinacia oleracea to Hydroponic and Aquaponic Water Quality Conditions

    Directory of Open Access Journals (Sweden)

    Daniel A. Vandam

    2017-05-01

    Full Text Available Spinach (Spinacia oleracea cv. Carmel was grown in a conventional glass greenhouse under three different nutrient solution treatments. Lighting and temperature conditions were identical. Six growing systems were used to provide a duplicate trough system for each of these three treatments. Six trials were harvested from each system over a two month time period. Two treatments received hydroponic nutrient inputs, with one treatment at pH 7.0 (referred to as H7 and the other at pH 5.8 (H5, and the third treatment was aquaponic (A7, receiving all of its nutrients from a single fish tank with koi (Cyprinus carpio except for chelated iron. System pH was regulated by adding K2CO3 to aquaponic systems and KOH to hydroponic systems. Comparisons made between treatments were total yield, leaf surface area, tissue elemental content, and dry weight to fresh weight ratio. Dry weight biomass yield values were not different in pairwise comparisons between treatments (A7 vs. H5: p = 0.59 fresh weight, p = 0.42 dry weight. Similarly, surface area results were not different between treatments. The important comparison was that A7 achieved the same growth as H5, the conventional pH with a complete inorganic nutrient solution, despite unbalanced and less than “ideal” nutrient concentrations in the A7 condition.

  7. Hydrolysis and photolysis of diacylhydrazines-type insect growth regulator JS-118 in aqueous solutions under abiotic conditions.

    Science.gov (United States)

    Hu, J-Y; Liu, C; Zhang, Y-C; Zheng, Z-X

    2009-05-01

    JS-118 is a diacylhydrazines-type insect growth regulator which is now used extensively in China. The hydrolysis and photolysis of the pesticide JS-118 in aqueous solutions have been assessed under natural and controlled conditions in this project. Hydrolysis experimental results show that JS-118 is quite stable in aqueous solutions in dark, with no significant variations be observed in degradation under various conditions. Abiotic hydrolysis is relatively unimportant compared to photolysis. The rate of photodecomposition of JS-118 in aqueous solutions follows first-order kinetics both in UV radiation and natural sunlight. The degradation rates are faster under UV light than sunlight, with the half-lives (t (1/2) = ln2/k) of 6.00-10.85 min and 6.63-10.16 day, respectively. Under UV light, two major photoproducts are detected, and tentatively identified according to HPLC-MS spectral information as N-t-butyl-N-(3,5-dimethylbenzoyl) and 3,7-dimethyl-benzoatedihydrofuran. The corresponding photolysis pathways of JS-118 are also proposed. The results obtained indicate that direct photoreaction is an important dissipation pathway of JS-118 in natural water systems.

  8. The Activity of Nodules of the Supernodulating Mutant Mtsunn Is not Limited by Photosynthesis under Optimal Growth Conditions

    Directory of Open Access Journals (Sweden)

    Ricardo A. Cabeza

    2014-04-01

    Full Text Available Legumes match the nodule number to the N demand of the plant. When a mutation in the regulatory mechanism deprives the plant of that ability, an excessive number of nodules are formed. These mutants show low productivity in the fields, mainly due to the high carbon burden caused through the necessity to supply numerous nodules. The objective of this study was to clarify whether through optimal conditions for growth and CO2 assimilation a higher nodule activity of a supernodulating mutant of Medicago truncatula (M. truncatula can be induced. Several experimental approaches reveal that under the conditions of our experiments, the nitrogen fixation of the supernodulating mutant, designated as sunn (super numeric nodules, was not limited by photosynthesis. Higher specific nitrogen fixation activity could not be induced through short- or long-term increases in CO2 assimilation around shoots. Furthermore, a whole plant P depletion induced a decline in nitrogen fixation, however this decline did not occur significantly earlier in sunn plants, nor was it more intense compared to the wild-type. However, a distinctly different pattern of nitrogen fixation during the day/night cycles of the experiment indicates that the control of N2 fixing activity of the large number of nodules is an additional problem for the productivity of supernodulating mutants.

  9. The Course of Parturition Affects Piglet Condition at Birth and Survival and Growth through the Nursery Phase.

    Science.gov (United States)

    Langendijk, Pieter; Fleuren, Marleen; van Hees, Hubèrt; van Kempen, Theo

    2018-04-24

    The aim of this study was to relate the course of parturition to the condition of piglets at birth, based on umbilical cord blood acid-base values, and relate the condition at birth to neonatal survival and performance up to 10 weeks of life. Data were collected from 37 spontaneous unassisted parturitions, and neonatal performance was based on observations of 516 piglets. Stillbirth rate increased from 2% in the first piglets, to 17% in piglets born 13th in the litter or later. This was aggravated in sows with longer than average stage II of parturition. Umbilical cord blood values also reflected the effect of birth order, with pH decreasing and lactate increasing in the course of parturition. Interestingly, sows that had a long expulsion stage of parturition also took longer to give birth to the first four piglets (r = 0.74), suggesting that sows with complicated parturition were already experiencing problems at the start of expulsion of piglets. Piglets with signs of asphyxia, based on umbilical blood lactate higher than 4.46 mmol/L, were slower to start suckling, had a higher risk of neonatal mortality, and had a slower growth rate over the first 10 weeks of life.

  10. The Activity of Nodules of the Supernodulating Mutant Mtsunn Is not Limited by Photosynthesis under Optimal Growth Conditions

    Science.gov (United States)

    Cabeza, Ricardo A.; Lingner, Annika; Liese, Rebecca; Sulieman, Saad; Senbayram, Mehmet; Tränkner, Merle; Dittert, Klaus; Schulze, Joachim

    2014-01-01

    Legumes match the nodule number to the N demand of the plant. When a mutation in the regulatory mechanism deprives the plant of that ability, an excessive number of nodules are formed. These mutants show low productivity in the fields, mainly due to the high carbon burden caused through the necessity to supply numerous nodules. The objective of this study was to clarify whether through optimal conditions for growth and CO2 assimilation a higher nodule activity of a supernodulating mutant of Medicago truncatula (M. truncatula) can be induced. Several experimental approaches reveal that under the conditions of our experiments, the nitrogen fixation of the supernodulating mutant, designated as sunn (super numeric nodules), was not limited by photosynthesis. Higher specific nitrogen fixation activity could not be induced through short- or long-term increases in CO2 assimilation around shoots. Furthermore, a whole plant P depletion induced a decline in nitrogen fixation, however this decline did not occur significantly earlier in sunn plants, nor was it more intense compared to the wild-type. However, a distinctly different pattern of nitrogen fixation during the day/night cycles of the experiment indicates that the control of N2 fixing activity of the large number of nodules is an additional problem for the productivity of supernodulating mutants. PMID:24727372

  11. Identification of melatonin in Trichoderma spp. and detection of melatonin content under controlled-stress growth conditions from T. asperellum.

    Science.gov (United States)

    Liu, Tong; Zhao, Fengzhou; Liu, Zhen; Zuo, Yuhu; Hou, Jumei; Wang, Yanjie

    2016-07-01

    T. koningii, T. harzianum, T. asperellum, T. longibrachiatum, and T. viride were analyzed using liquid chromatography-tandem mass spectrometry to determine whether melatonin is present. Results showed that there were abundant amounts of endogenous melatonin in five Trichoderma species, but no melatonin was found in any of the culture filtrates. T. asperellum had the highest amount of melatonin (27.588 ± 0.326 μg g(-1) dry mass), followed by T. koningii, T. harzianum, T. longibrachiatum, and T. viride. The endogenous melatonin content of T. asperellum in controlled-stress growth conditions was also detected. The data showed that chemical stressors (CdCl2 , CuSO4 , and H2 O2 ) provoked an increase in endogenous melatonin levels. CdCl2 had the highest stimulatory effect on melatonin production, as the product reached reaching up to three times the melatonin content of the control. NaCl stimulated a decrease of melatonin. Acidic conditions (pH 3 and pH 5) as well as slightly alkaline conditions (pH 9) resulted in an increase in the melatonin content, whereas pH11 resulted in a significant decrease in the melatonin content, only 12.276 ± 0.205 μg g(-1) dry mass. The current study is first to report melatonin content and the change of melatonin content under different stress situations in Trichoderma spp. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. The influence of antioxidants 'TIOFAN' and 'FANTOX 11-1' on physiological growth of broilers in conditions of intoxication with lead and cadmium salts

    International Nuclear Information System (INIS)

    Koval, Yu.I.; Bokova, T.I.; Kandalintseva, N.V.

    2008-01-01

    The purpose of research is to study the influence of antioxidants 'TIOFAN' and 'FANTOX 11-1' on physiological growth of broilers in conditions of intoxication with lead and cadmium salts. The growth and development of bird in conditions of intoxication with heavy metals and by using of antioxidants as detoxicant is studied. The biochemical blood values on application of antioxidants and without them in conditions of intoxication are determined. The most effective preparation raising of birds productivity and it's optimal concentration is established.

  13. Antimicrobial gageomacrolactins characterized from the fermentation of the marine-derived bacterium Bacillus subtilis under optimum growth conditions.

    Science.gov (United States)

    Tareq, Fakir Shahidullah; Kim, Ji Hye; Lee, Min Ah; Lee, Hyi-Seung; Lee, Jong-Seok; Lee, Yeon-Ju; Shin, Hee Jae

    2013-04-10

    Marine bacteria are a potential source of structurally diversified bioactive secondary metabolites that are not found in terrestrial sources. In our continuous effort to search for new antimicrobial agents from marine-derived bacteria, we isolated bacterial strain 109GGC020 from a marine sediment sample collected from Gageocho, Republic of Korea. The strain was identified as Bacillus subtilis based on a 16s rRNA sequence analysis. After a 7-day fermentation of the B. subtilis strain under optimum growth conditions three new and four known secondary metabolites were discovered using chromatographic procedures, and their biological activities were evaluated against both bacteria and crop-devastating fungi. The discovered metabolites were confirmed by extensive 2D NMR and high-resolution ESI-MS data analyses to have the structures of new macrolactin derivatives gageomacrolactins 1-3 and known macrolactins A (4), B (5), F (6), and W (7). The stereoconfigurations of 1-3 were assigned based on coupling constant values, chemical derivatization studies, and a literature review. The coupling constants were very crucial to determine the relative geometries of olefins in 1-3 because of overlap of the ¹H NMR signals. The NMR data of these compounds were recorded in different solvents to overcome this problem and obtain accurate coupling constant values. The new macrolactin derivatives 1-3 displayed good antibiotic properties against both Gram-positive (S. aureus, B. subtilis, and B. cereus) and Gram-negative (E. coli, S. typhi, and P. aeruginosa) bacteria with minimum inhibitory concentration (MIC) values of 0.02-0.05 μM. Additionally, the antifungal activities of 1-7 were evaluated against pathogenic fungi and found to inhibit mycelial growth of A. niger, B. cinerea, C. acutatum, C. albicans, and R. solani with MIC values of 0.04-0.3 μM, demonstrating that these compounds were good fungicides.

  14. Transgenic alfalfa (Medicago sativa) with increased sucrose phosphate synthase activity shows enhanced growth when grown under N2-fixing conditions.

    Science.gov (United States)

    Gebril, Sayed; Seger, Mark; Villanueva, Fabiola Muro; Ortega, Jose Luis; Bagga, Suman; Sengupta-Gopalan, Champa

    2015-10-01

    Overexpression of SPS in alfalfa is accompanied by early flowering, increased plant growth and an increase in elemental N and protein content when grown under N2-fixing conditions. Sucrose phosphate synthase (SPS; EC 2.3.1.14) is the key enzyme in the synthesis of sucrose in plants. The outcome of overexpression of SPS in different plants using transgenic approaches has been quite varied, but the general consensus is that increased SPS activity is associated with the production of new sinks and increased sink strength. In legumes, the root nodule is a strong C sink and in this study our objective was to see how increasing SPS activity in a legume would affect nodule number and function. Here we have transformed alfalfa (Medicago sativa, cv. Regen SY), with a maize SPS gene driven by the constitutive CaMV35S promoter. Our results showed that overexpression of SPS in alfalfa, is accompanied by an increase in nodule number and mass and an overall increase in nitrogenase activity at the whole plant level. The nodules exhibited an increase in the level of key enzymes contributing to N assimilation including glutamine synthetase and asparagine synthetase. Moreover, the stems of the transformants showed higher level of the transport amino acids, Asx, indicating increased export of N from the nodules. The transformants exhibited a dramatic increase in growth both of the shoots and roots, and earlier flowering time, leading to increased yields. Moreover, the transformants showed an increase in elemental N and protein content. The overall conclusion is that increased SPS activity improves the N status and plant performance, suggesting that the availability of more C in the form of sucrose enhances N acquisition and assimilation in the nodules.

  15. Sterol synthesis and cell size distribution under oscillatory growth conditions in Saccharomyces cerevisiae scale-down cultivations.

    Science.gov (United States)

    Marbà-Ardébol, Anna-Maria; Bockisch, Anika; Neubauer, Peter; Junne, Stefan

    2018-02-01

    Physiological responses of yeast to oscillatory environments as they appear in the liquid phase in large-scale bioreactors have been the subject of past studies. So far, however, the impact on the sterol content and intracellular regulation remains to be investigated. Since oxygen is a cofactor in several reaction steps within sterol metabolism, changes in oxygen availability, as occurs in production-scale aerated bioreactors, might have an influence on the regulation and incorporation of free sterols into the cell lipid layer. Therefore, sterol and fatty acid synthesis in two- and three-compartment scale-down Saccharomyces cerevisiae cultivation were studied and compared with typical values obtained in homogeneous lab-scale cultivations. While cells were exposed to oscillating substrate and oxygen availability in the scale-down cultivations, growth was reduced and accumulation of carboxylic acids was increased. Sterol synthesis was elevated to ergosterol at the same time. The higher fluxes led to increased concentrations of esterified sterols. The cells thus seem to utilize the increased availability of precursors to fill their sterol reservoirs; however, this seems to be limited in the three-compartment reactor cultivation due to a prolonged exposure to oxygen limitation. Besides, a larger heterogeneity within the single-cell size distribution was observed under oscillatory growth conditions with three-dimensional holographic microscopy. Hence the impact of gradients is also observable at the morphological level. The consideration of such a single-cell-based analysis provides useful information about the homogeneity of responses among the population. Copyright © 2017 John Wiley & Sons, Ltd.

  16. Influence of the growth conditions on the optical and structural properties of self-assembled InAs/GaAs quantum dots for low As/In ratio

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, Samet; Suyolcu, Y. Eren [Advanced Technologies Research Unit: Nanotechnology, Graduate School of Sciences, Anadolu University, Yunusemre Campus, 26470 Eskisehir (Turkey); Turan, Servet [Department of Materials Science and Engineering, Anadolu University, Iki Eylul Campus, 26555 Eskisehir (Turkey); Aslan, Bulent, E-mail: bulentaslan@anadolu.edu.tr [Department of Physics, Anadolu University, Yunusemre Campus, 26470 Eskisehir (Turkey)

    2017-01-15

    Highlights: • Effects of systematically changed growth conditions on InAs/GaAs QDs were studied. • Growths were optimized for low As/In flux ratio to obtain well-resolved PL spectra. • XRD rocking curve signal fitting was used to analyze the samples. • XRD analysis reflects the overall tendency of the QD density and WL behavior. - Abstract: We report on the growth and characterization of self-assembled InAs/GaAs quantum dots (QDs). The influence of the systematically changed growth conditions on the opto-electronic and structural properties of the QDs were investigated. Combination of the amount of the deposited InAs, growth temperature and growth rate were optimized for low As/In flux ratio to obtain well-resolved ground and excited states in the low temperature photoluminescence (PL) spectra. SEM and TEM techniques were also used for the characterization of QDs. The results were evaluated simply through the conservation of mass approximation and the x-ray diffraction measurements with fitted curves. The extracted InAs and wetting layer thicknesses were brought out that the XRD analysis reflects the overall tendency of the QD density change and WL behaviors in response to the changes in growth conditions.

  17. Effect of restricted feeding under rearing on reproduction, body condition and blood metabolites of rabbit does selected for growth rate

    Directory of Open Access Journals (Sweden)

    C. Naturil-Alfonso

    2017-12-01

    Full Text Available Young rabbit females selected for growth rate can have nutritional needs which may not be met by the common practice of feed restriction during rearing in commercial rabbit production. The aim of this study was to analyse the effect of two different feeding programmes: restricted and ad libitum feeding, applied in young rabbit females for one month at the end of rearing, on reproductive performance, body condition and circulating metabolic hormones and metabolites in a rabbit line selected by growth rate in 3 consecutive reproductive cycles. Thus, twenty-four 16-week-old does were randomly assigned to a group in which the daily recommended nutrient intakes were satisfied (fed restricted: 130 g/day, n=13 or a group fed to satiety (ad libitum: 235.5 g/day, n=11 during one month. Then, all does were inseminated in 3 consecutive cycles using a 42-day reproductive cycle. Measurements of does’ body weight, perirenal fat thickness and plasma leptin, non-esterified-fatty-acids (NEFA, beta-hydroxybutyrate (BOHB and fructosamine were performed at artificial insemination (AI, parturition and weaning time in 3 consecutive cycles. Reproductive performance of does was evaluated based on fertility, litter size at parturition, prolificacy and productivity. Differences in body weight were found only in the 1st cycle, ad libitum fed females being heavier than restricted ones. Nevertheless, body weight variances disappeared in later cycles. No differences were found in perirenal fat thickness. Finally, in ad libitum fed females slight differences were found in plasma levels of NEFAs (452 vs. 258 μekv/L and 527 vs. 306 μekv/L for 1st and 2nd cycles and BOHB (0.26 vs. 0.03 mM for 2nd cycle, but disappeared in the 3rd reproductive cycle. Fertility, prolificacy and productivity was not significantly affected by the feeding programme. Nevertheless, total litter size showed to be higher in ad libitum fed females at second parturition (8.7 vs. 5.9 kits. Therefore

  18. The effect of irradiance on long-term skeletal growth and net photosynthesis in Galaxea fascicularis under four light conditions.

    NARCIS (Netherlands)

    Schutter, M.; Velthoven, van B.; Janse, M.; Osinga, R.; Janssen, M.G.J.; Wijffels, R.H.; Verreth, J.A.J.

    2008-01-01

    The relation between irradiance, skeletal growth and net photosynthesis was studied for the scleractinian coral Galaxea fascicularis to provide experimental evidence for mediation of light-enhanced calcification through photosynthesis. The hypothesis was tested that skeletal growth and

  19. Numerical modeling of Czochralski growth of Li2MoO4 crystals for heat-scintillation cryogenic bolometers

    Science.gov (United States)

    Stelian, Carmen; Velázquez, Matias; Veber, Philippe; Ahmine, Abdelmounaim; Sand, Jean-Baptiste; Buşe, Gabriel; Cabane, Hugues; Duffar, Thierry

    2018-06-01

    Lithium molybdate Li2MoO4 (LMO) crystals of mass ranging between 350 and 500 g are excellent candidates to build heat-scintillation cryogenic bolometers likely to be used for the detection of rare events in astroparticle physics. In this work, numerical modeling is applied in order to investigate the Czochralski growth of Li2MoO4 crystals in an inductive furnace. The numerical model was validated by comparing the numerical predictions of the crystal-melt interface shape to experimental visualization of the growth interface. Modeling was performed for two different Czochralski furnaces that use inductive heating. The simulation of the first furnace, which was used to grow Li2MoO4 crystals of 3-4 cm in diameter, reveals non-optimal heat transfer conditions for obtaining good quality crystals. The second furnace, which will be used to grow crystals of 5 cm in diameter, was numerically optimized in order to reduce the temperature gradients in the crystal and to avoid fast crystallization of the bath at the later stages of the growth process.

  20. Influence of nanoparticle addition on the formation and growth of intermetallic compounds (IMCs) in Cu/Sn–Ag–Cu/Cu solder joint during different thermal conditions

    Science.gov (United States)

    Ting Tan, Ai; Wen Tan, Ai; Yusof, Farazila

    2015-01-01

    Nanocomposite lead-free solders are gaining prominence as replacements for conventional lead-free solders such as Sn–Ag–Cu solder in the electronic packaging industry. They are fabricated by adding nanoparticles such as metallic and ceramic particles into conventional lead-free solder. It is reported that the addition of such nanoparticles could strengthen the solder matrix, refine the intermetallic compounds (IMCs) formed and suppress the growth of IMCs when the joint is subjected to different thermal conditions such as thermal aging and thermal cycling. In this paper, we first review the fundamental studies on the formation and growth of IMCs in lead-free solder joints. Subsequently, we discuss the effect of the addition of nanoparticles on IMC formation and their growth under several thermal conditions. Finally, an outlook on the future growth of research in the fabrication of nanocomposite solder is provided. PMID:27877786

  1. Influence of nanoparticle addition on the formation and growth of intermetallic compounds (IMCs) in Cu/Sn–Ag–Cu/Cu solder joint during different thermal conditions

    International Nuclear Information System (INIS)

    Ting Tan, Ai; Wen Tan, Ai; Yusof, Farazila

    2015-01-01

    Nanocomposite lead-free solders are gaining prominence as replacements for conventional lead-free solders such as Sn–Ag–Cu solder in the electronic packaging industry. They are fabricated by adding nanoparticles such as metallic and ceramic particles into conventional lead-free solder. It is reported that the addition of such nanoparticles could strengthen the solder matrix, refine the intermetallic compounds (IMCs) formed and suppress the growth of IMCs when the joint is subjected to different thermal conditions such as thermal aging and thermal cycling. In this paper, we first review the fundamental studies on the formation and growth of IMCs in lead-free solder joints. Subsequently, we discuss the effect of the addition of nanoparticles on IMC formation and their growth under several thermal conditions. Finally, an outlook on the future growth of research in the fabrication of nanocomposite solder is provided. (review)

  2. Effect of indium accumulation on the characteristics of a-plane InN epi-films under different growth conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lo, Yun-Yo [Institute of Photonics, National Changhua University of Education, Changhua, Taiwan, ROC (China); Huang, Man-Fang, E-mail: mfhuang@cc.ncue.edu.tw [Institute of Photonics, National Changhua University of Education, Changhua, Taiwan, ROC (China); Chiang, Yu-Chia [Institute of Photonics, National Changhua University of Education, Changhua, Taiwan, ROC (China); Fan, Jenn-Chyuan [Department of Electronic Engineering, Nan Kai University of Technology, Nantou, Taiwan, ROC (China)

    2015-08-31

    This study investigated the influence of indium accumulation happened on the surface of a-plane InN grown under different growth conditions. Three different growth rates with N/In ratio from stoichiometric to N-rich were used to grow a-plane InN epifilms on GaN-buffered r-plane sapphires by plasma-assisted molecular beam epitaxy. When a-plane InN was grown above 500 °C with a high growth rate, abnormally high in-situ reflectivity was found during a-plane InN growth, which was resulted from indium accumulation on surface owing to In-N bonding difficulty on certain crystal faces of a-plane InN surface. Even using excess N-flux, indium accumulation could still be found in initial growth and formed 3-dimension-like patterns on a-plane InN surface which resulted in rough surface morphology. By reducing growth rate, surface roughness was improved because indium atoms could have more time to migrate to suitable position. Nonetheless, basal stacking fault density and crystal anisotropic property were not affected by growth rate. - Highlights: • High growth temperature could cause indium accumulation on a-plane InN surface. • Indium accumulation on a-plane InN surface causes rough surface. • Low growth rate improves surface morphology but not crystal quality.

  3. Growth responses and accumulation of soluble sugars in Inga marginata Wild. (Fabaceae) subjected to flooding under contrasting light conditions.

    Science.gov (United States)

    Bender, B; Capellesso, E S; Lottici, M E; Sentkovski, J; Mielniczki-Pereira, A A; Rosa, L M G; Sausen, T L

    2017-01-01

    Flood events in riparian forests of southern Brazil, can be characterized as unpredictable and of low magnitude with an average duration of less than 15 days. Inga marginata is an evergreen tree which grows in Southeast South America on a wide range of environments, including riparian forests. In this paper, the interactive effects of the light environment and soil flooding on morphological parameters of I. marginata were examined. Seedlings were acclimated in two contrasting light conditions: sun or shade for 30 days. Sun and shade plants were subjected to soil flooding for two periods; five or 15 days. After 5 days, the interaction between flooding and light did not affect growth, chlorophyll content and dry mass or the root-shoot ratio. After 15 days, flooded plants from the sunny treatment had a lower shoot dry mass compared to control sun plants and flooded plants from the shaded treatment. Moreover, the higher dry mass observed for shade plants compared to sun plants, following flooding, can also be directly associated with a higher content of soluble sugars. Shade plants of I. marginata showed a greater acclimation to soil waterlogging. This acclimation appears to be associated with a larger accumulation of soluble sugars compared to non-flooded plants. The responses observed on the shade plants appear to be decisive to indicate the use of I. marginata in degraded areas.

  4. Growth and development of tomato plants Lycopersicon Esculentum Mill. under different saline conditions by fertirrigation with pretreated cheese whey wastewater.

    Science.gov (United States)

    Prazeres, Ana R; Carvalho, Fátima; Rivas, Javier; Patanita, Manuel; Dôres, Jóse

    2013-01-01

    Pretreated cheese whey wastewater (CWW) has been used at different salinity levels: 1.75, 2.22, 3.22, 5.02 and 10.02 dS m(-1) and compared with fresh water (1.44 dS m(-1)). Two cultivars (cv.) of the tomato plant Lycopersicon Esculentum Mill. (Roma and Rio Grande) were exposed to saline conditions for 72 days. Salinity level (treatment) had no significant effects on the fresh weight and dry matter of the leaves, stems and roots. Similar results were found when specific leaf area, leaflet area, ramifications number of 1st order/plant, stem diameter and length, nodes number/stem and primary root length were considered. Conversely, the salinity level significantly influenced the Soil Plant Analysis Development (SPAD) index and the distance between nodes in the plant stem. In the first case, an increase of 21% was obtained in the salinity levels of 5.02 and 10.02 dS m(-1) for cv. Rio Grande, compared with the control run. The results showed that the pretreated CWW can be a source of nutrients for tomato plants, with reduced effects on growth and development.

  5. Growth conditions for the biomass yield of two methanol utilizing yeast spp. , Candida sp. and Rhodotorula sp

    Energy Technology Data Exchange (ETDEWEB)

    Hong, S.W.

    1976-01-01

    More than 580 MeOH utilizing yeasts were isolated from samples collected throughout South Korea. Of these, 2 strains showed good biomass yield and were selected and tentatively identified as Candida melinii and Rhodotorula glutinis glutinis. Experiments on growth conditions for these 2 species were performed. Optimum pH was 2.6 for Candida, 5.2 for Rhodotorula, and the temperature optimum was 28 to 30/sup 0/ for both. Maximum biomass yield was 4.32 g/L for Candida and 4.2l g/L for Rhodotorula. Optimum concentrations were (NH/sub 4/)/sub 2/SO/sub 4/ 0.3%, Mg/sup +/ 400 ppM, Fe/sup +/ 10 to 15 ppM for Candida and (NH/sub 4/)/sub 2/SO/sub 4/ 0.3% Mg/sup +/ 600 ppM Ca/sup +/ 2 ppM for Rhodotorula. Biotin stimulated Candida. Protein contents of the dry cell biomass were 39.3% in Candida and 44.0% in Rhodotorula.

  6. Kinetics of U(VI) reduction by a dissimilatory Fe(III)-reducing bacterium under non-growth conditions

    International Nuclear Information System (INIS)

    Truex, M.J.; Peyton, B.M.; Valentine, N.B.; Gorby, Y.A.

    1997-01-01

    Dissimilatory metal-reducing microorganisms may be useful in processes designed for selective removal of uranium from aqueous streams. These bacteria can use U(VI) as an electron acceptor and thereby reduce soluble U(VI) to insoluble U(IV). While significant research has been devoted to demonstrating and describing the mechanism of dissimilatory metal reduction, the reaction kinetics necessary to apply this for remediation processes have not been adequately defined. In this study, pure culture Shewanella alga strain BrY reduced U(VI) under non-growth conditions in the presence of excess lactate as the electron donor. Initial U(VI) concentrations ranged from 13 to 1,680microM. A maximum specific U(VI) reduction rate of 2.37 micromole-U(VI)/(mg-biomass h) and Monod half-saturation coefficient of 132 microM-U(VI) were calculated from measured U(VI) reduction rates. U(VI) reduction activity was sustained at 60% of this rate for at least 80 h. The initial presence of oxygen at a concentration equal to atmospheric saturation at 22 C delays but does not prevent U(VI) reduction. The rate of U(VI) reduction by BrY is comparable or better than rates reported for other metal reducing species. BrY reduces U(VI) at a rate that is 30% of its Fe(III) reduction rate

  7. Effect of cultural conditions on the seed-to-seed growth of Arabidopsis and Cardamine - A study of growth rates and reproductive development as affected by test tube seals

    Science.gov (United States)

    Hoshizaki, T.

    1982-01-01

    The effects of test tube seals on the growth, flowering, and seed pod formation of Arabidopsis thaliana (L.) Heynh., mouse ear cress, and Cardamine oligosperma Nutt, bitter cress, are studied in order to assess the conditions used in weightlessness experiments. Among other results, it is found that the growth (height) and flowering (date of bud appearance) were suppressed in mouse ear cress in tubes sealed with Saran. Seed pod formation which occurred by day 45 in open-to-air controls, was still lacking in the sealed plants even up to day 124. The growth and flowering of bitter cress were also suppressed by the Saran seal, although up to day 55 the Saran-sealed plants were taller. It is suggested that atmospheric composition was the cause of the suppression of growth, flowering, and seed pod development in these plants, since the mouse ear cress renewed their growth and then set seed pods after the Saran seal was ruptured.

  8. Co-inoculation with Rhizobium and plant growth promoting rhizobacteria (PGPR for inducing salinity tolerance in mung bean under field condition of semi arid climate

    Directory of Open Access Journals (Sweden)

    Muhammad Aamir

    2013-04-01

    Full Text Available Salinity stress severely affects the growth, nodulation and yield of mung bean (Vigna radiata L.. However, its growth can be improved under salinity stress by inoculation/co-inoculation with rhizobia and plant growth promoting rhizobacteria (PGPR containing 1-Aminocyclopropane-1-carboxylic acid (ACC deaminase enzyme. ACC-deaminase containing bacteria regulate the stress induced ethylene production by hydrolyzing the ACC (immediate precursor of ethylene into ammonia and ketobutyric acid, thus improve plant growth by lowering the ethylene level. A study was conducted under salt affected field conditions where pre-isolated strains of Rhizobium and PGPR were used alone as well as in combination for mitigating the salinity stress on growth, nodulation and yield of mung bean by following the randomized complete block design (RCBD. The data were recorded and analyzed statistically to see the difference among treatments.

  9. Interactive effects of temperature and light during deep convection: a case study on growth and condition of the diatom Thalassiosira weissflogii

    DEFF Research Database (Denmark)

    Walter, B.; Peters, J.; van Beusekom, J. E. E.

    2015-01-01

    pulses of a higher light intensity (120 mmol m22 s21, 2/22 hlight/dark). Both experimental light conditions offered the same daily light dose. No growth was observed at temperatures below 88C. Above 88C, growth rates were significantly higher under low light conditions compared with those of short pulsed...... light exposures, indicating a higher efficiency of light utilization. This could be related to (i) a higher content of Chl a per cell in the lowlight trial and/or (ii) a more efficient transfer of light energy into growth as indicated by constantly low carbohydrate levels.In contrast, pulsed intense...... did not provide sufficient light to reach full light saturation. In general, photosynthesis was more strongly affected by temperature under pulsed light than under low light conditions. Our results indicate that model estimates of primary production in relation to deep convection, which are based...

  10. Characteristics of light and heat conditions of a chamber with prism light guides and electrodeless discharge lamps and its effect on growth of tomato and cucumber seedlings

    International Nuclear Information System (INIS)

    Higashide, T.; Shimaji, H.; Hamamoto, H.; Shimazu, T.; Takaichi, M.

    2004-01-01

    Summary Light and heat conditions were measured in a growth chamber with prism light guides and electrolodeless discharge lamps (LP chamber) , a growth chamber with metal halide lamps (MH chamber) and a glasshouse. In the LP chamber, photosynthetic photon flux (PPF) was larger and heat radiation was smaller than in the others. Growth of tomato seedlings increased in high PPF condition. However, the growth with high PPF in the MH chamber was restricted. Leaf temperature with high PPF in the MH chamber was higher than that in the LP chamber. We thought that excessive heat had restricted the growth with high PPF in the MH chamber. There were no differences in nutrient or water absorption, except with conditions of the largest heat radiation and the lowest PPF. Cucumber seedlings were grown with high PPF in the LP chamber. The growth at high temperatures was smaller than that at the optimum temperature. However the leaf number at high temperatures was higher than that at the optimum temperature

  11. The effects of intermittent exposure to low pH and oxygen conditions on survival and growth of juvenile red abalone

    Science.gov (United States)

    Kim, T. W.; Barry, J. P.; Micheli, F.

    2013-02-01

    Exposure of nearshore animals to hypoxic, low pH waters upwelled from below the continental shelf and advected near the coast may be stressful to marine organisms and lead to impaired physiological performance. We mimicked upwelling conditions in the laboratory and tested the effect of fluctuating exposure to water with low pH and/or low oxygen levels on the mortality and growth of juvenile red abalone (Haliotis rufescens, shell length 5-10 mm). Mortality rates of juvenile abalone exposed to low pH (7.5, total scale) and low O2 (40% saturation, 5 mg L-1) conditions for periods of 3 to 6 h every 3-5 days over 2 weeks did not differ from those exposed to control conditions (O2: 100% saturation, 12 mg L-1; pH 8.0). However, when exposure was extended to 24 h repeated twice over a 15 day period, juveniles experienced higher mortality in the low oxygen treatments compared to control conditions, regardless of pH levels (pH 7.5 vs. 8.0). Growth rates were reduced significantly when juveniles were exposed to low pH or low oxygen treatments and the growth was lowest when low pH exposure was combined with low O2. Furthermore, individual variation of growth rate increased when they were exposed to low pH and low O2 conditions. These results indicate that prolonged exposure to low oxygen levels is detrimental for the survival of red abalone, whereas both pH and oxygen is a crucial factor for their growth. However, given the higher individual variation in growth rate, they may have an ability to adapt to extended exposure to upwelling conditions.

  12. Compensation effect of bacterium containing biofertilizer on the growth of Cucumis sativus L. under Al-stress conditions.

    Science.gov (United States)

    Tóth, Brigitta; Lévai, L; Kovács, B; Varga, Mária Borbélyné; Veres, Szilvia

    2013-03-01

    Biofertilizers are used to improve soil fertility and plant production in sustainable agriculture. However, their applicability depends on several environmental parameters. The aim of our study was to evaluate the effect of free-living bacteria containing fertilizer on the growth of cucumber (Cucumis sativus L. cvs. Delicates) under aluminium (Al) stress. Different responses to Al stress of cucumber growth parameters were examined in terms of root elongation and physiological traits, such as Spad index (relative chlorophyll value), biomass accumulation of root and shoot, Al uptake and selected element contents (Fe, Mn, Zn, Mg) of leaves and root. The applied bacteria containing biofertilizer contains Azotobacter chroococcum and Bacillus megaterium. The dry weights of cucumber shoots and roots decreased in line with the increasing Al concentration. Due to different Al treatments (10-3 M, 10-4 M) higher Al concentration was observed in the leaves, while the amounts of other elements (Fe, Mn, Zn, Mg) decreased. This high Al content of the leaves decreased below the control value when biofertilizer was applied. In the case of the roots the additional biofertilizer treatments compensated the effect of Al. The relative chlorophyll content was reduced during Al-stress in older plants and the biofertilizer moderated this effect. The root/shoot ratio was decreased in all the Al-treatments in comparison to the control. The living bacteria containing fertilizer also had a modifying effect. The root/shoot ratio increased at the 10-4 M Al2(SO4)2 + biofertilizer and 10-4 M Al(NO3)3 + biofertilizer treatments compared to the control and Al-treatments. According to our results the biofertilizer is an alternative nutrient supply for replacing chemical fertilizers because it enhances dry matter production. Biofertilizer usage is also offered under Al polluted environmental conditions. Although, the nutrient solution is a clean system where we can examine the main processes without

  13. The Conditions under which Growth-Fostering Relationships Promote Resilience and Alleviate Psychological Distress among Sexual Minorities: Applications of Relational Cultural Theory

    Science.gov (United States)

    Mereish, Ethan H.; Poteat, V. Paul

    2015-01-01

    Relational cultural theory posits that resilience and psychological growth are rooted in relational connections and are facilitated through growth-fostering relationships. Framed within this theory, the current study examined the associations between growth-fostering relationships (i.e., relationships characterized by authenticity and mutuality) with a close friend and psychological distress among sexual minorities. More specifically, we tested the moderating effects of individuals’ internalized homophobia and their friend’s sexual orientation on the associations between growth-fostering relationship with their close friend and level of psychological distress. A sample of sexual minorities (N = 661) were recruited online and completed a questionnaire. The 3-way interaction between (a) growth-fostering relationship with a close friend, (b) the close friend’s sexual orientation, and (c) internalized homophobia was significant in predicting psychological distress. Among participants with low levels of internalized homophobia, a stronger growth-fostering relationship with a close heterosexual or LGBT friend was associated with less psychological distress. Among participants with high levels of internalized homophobia, a stronger growth-fostering relationship with a close LGBT friend was associated with less psychological distress but not with a heterosexual friend. Our results demonstrate that growth-fostering relationships may be associated with less psychological distress but under specific conditions. These findings illuminate a potential mechanism for sexual minorities’ resilience and provide support for relational cultural theory. Understanding resilience factors among sexual minorities is critical for culturally sensitive and affirmative clinical practice and future research. PMID:26380836

  14. Influence of growth conditions and surface reaction byproducts on GaN grown via metal organic molecular beam epitaxy: Toward an understanding of surface reaction chemistry

    Science.gov (United States)

    Pritchett, David; Henderson, Walter; Burnham, Shawn D.; Doolittle, W. Alan

    2006-04-01

    The surface reaction byproducts during the growth of GaN films via metal organic molecular beam epitaxy (MOMBE) were investigated as a means to optimize material properties. Ethylene and ethane were identified as the dominant surface reaction hydrocarbon byproducts, averaging 27.63% and 7.15% of the total gas content present during growth. Intense ultraviolet (UV) photoexcitation during growth was found to significantly increase the abundance of ethylene and ethane while reducing the presence of H2 and N2. At 920°C, UV excitation was shown to enhance growth rate and crystalline quality while reducing carbon incorporation. Over a limited growth condition range, a 4.5×1019-3.4×1020 cm-3 variation in carbon incorporation was achieved at constant high vacuum. Coupled with growth rate gains, UV excitation yielded films with ˜58% less integrated carbon content. Structural material property variations are reported for various ammonia flows and growth temperatures. The results suggest that high carbon incorporation can be achieved and regulated during MOMBE growth and that in-situ optimization through hydrocarbon analysis may provide further enhancement in the allowable carbon concentration range.

  15. Plant Signals Disrupt (regulate?) Arbuscular Mycorrhizal Fungal Growth Under Enhanced Ozone and CO2 Growing Conditions for Populus tremuloides

    Science.gov (United States)

    Miller, R. M.; Podila, G. K.

    2008-12-01

    An understanding of the genetic determinants of keystone symbiotic relationships is essential to elucidating adaptive mechanisms influencing higher-order processes, including shifts in community composition following environmental perturbations. The Aspen FACE project offers a unique opportunity to address adaptive processes with an imposed three way interaction experiment composed of the atmospheric pollutant ozone (eO3), elevated CO2 (eCO2) fumigations, five Populus tremuloides (aspen) genotypes, and both arbuscular mycorrhizal and ectomycorrhizal fungal interactions. The 10 year time span of this experiment has allowed for a realistic and mechanistic understanding of above ground responses of the aspen genotypes to eCO2, eO3 and the interaction effects of eCO2 and eO3. Even so, treatment influences to the below ground, including carbon allocation to roots and associated mycorrhizal symbionts, and rhizosphere dynamics are just beginning to be understood. We hypothesized that mycorrhizal fungal responses to eCO2, eO3, and the interaction effects of eCO2+eO3 are conditioned by the degree of response of their aspen hosts. We intend to describe the molecular mechanisms of an important critical interaction between host and fungus using microarray analysis of expression profiles, as well as metabolic profiling of aspen roots and their associated mycorrhizal partner, the arbuscular mycorrhizal fungus (AMF) Glomus intraradices, under eCO2, eO3 and eCO2+eO3. We present evidence that host-derived factors, expressed in response to eCO2+eO3, trigger responses in Glomus leading to the partitioning or metabolic shift in lipid biosynthesis that is associated with reduced extraradical hyphae growth and altered lipid metabolism. We then scale these lower-level responses to give better insight to fungal intraradical and extraradical allocation of biomass and fungal and root lipid and carbohydrate content in association with aspen genotype responses to the imposed treatments. By

  16. Near-bed environmental conditions influencing cold-water coral growth on Viosca Knoll, Gulf of Mexico

    Science.gov (United States)

    Mienis, F.; Duineveld, G.; Davies, A. J.; Weering, T. V.; Ross, S.; Roberts, M.; Seim, H.

    2010-12-01

    transported to the area. Sediment trap samples show a similar pattern and high mass fluxes are found, varying between 1.1-4.5 gm-2day-1. High mass fluxes and turbidity values can be related to an increased input of material coming from the Mississippi River. The environmental conditions on Viosca Knoll resemble those recorded in CWC areas on the European margin. Even though oxygen values are low and high mass fluxes were recorded, the CWC ecosystem thrives at present. The proximity of the area to the Mississippi River may benefit the corals by increasing the food supply. Migration of zooplankton and episodes of fresh particle supply from surface water form the mechanisms of food delivery, influencing CWC growth. Subsequently baffling of particles between the coral framework likely increases lateral extension and reef growth.

  17. In vitro stimulation of vascular endothelial growth factor by borate-based glass fibers under dynamic flow conditions

    International Nuclear Information System (INIS)

    Chen, Sisi; Yang, Qingbo; Brow, Richard K.; Liu, Kun; Brow, Katherine A.; Ma, Yinfa

    2017-01-01

    Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying biochemical and cellular mechanisms remain unclear. In this study, dynamic flow culturing modules were designed to simulate the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, thus to better investigate the mechanisms underlying the biocompatibility and functionality of borate-based glass materials. Glass fibers were dosed either upstream or in contact with the pre-seeded cells in the dynamic flow module. Two types of borate glasses, doped with (1605) or without (13-93B3) CuO and ZnO, were studied along with the silicate-based glass, 45S5. Substantial fiber dissolution in cell culture medium was observed, leading to the release of ions (boron, sodium and potassium) and the deposition of a calcium phosphate phase. Different levels of vascular endothelial growth factor secretion were observed from cells exposed to these three glass fibers, and the copper/zinc containing borate 1605 fibers exhibited the most positive influence. These results indicate that dynamic studies of in vitro bioactivity provide useful information to understand the in vivo response to bioactive borate glasses. - Highlights: • Novel dynamic flow cell culture modules were designed. • Bioactive glass fibers were evaluated for their effects on VEGF secretion. • Borate-based glass fibers stimulate VEGF secretion under dynamic condition. • CuO and ZnO doped borate-based glass fibers stimulate the greatest VEGF release.

  18. In vitro stimulation of vascular endothelial growth factor by borate-based glass fibers under dynamic flow conditions

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Sisi [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Yang, Qingbo [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell, and Single Molecule Monitoring, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Brow, Richard K. [Department of Material Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Liu, Kun [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell, and Single Molecule Monitoring, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Brow, Katherine A. [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Ma, Yinfa [Department of Chemistry, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Biomedical Science and Engineering, Missouri University of Science and Technology, Rolla, MO 65409 (United States); Center for Single Nanoparticle, Single Cell, and Single Molecule Monitoring, Missouri University of Science and Technology, Rolla, MO 65409 (United States); and others

    2017-04-01

    Bioactive borate glass has been recognized to have both hard and soft tissue repair and regeneration capabilities through stimulating both osteogenesis and angiogenesis. However, the underlying biochemical and cellular mechanisms remain unclear. In this study, dynamic flow culturing modules were designed to simulate the micro-environment near the vascular depletion and hyperplasia area in wound-healing regions, thus to better investigate the mechanisms underlying the biocompatibility and functionality of borate-based glass materials. Glass fibers were dosed either upstream or in contact with the pre-seeded cells in the dynamic flow module. Two types of borate glasses, doped with (1605) or without (13-93B3) CuO and ZnO, were studied along with the silicate-based glass, 45S5. Substantial fiber dissolution in cell culture medium was observed, leading to the release of ions (boron, sodium and potassium) and the deposition of a calcium phosphate phase. Different levels of vascular endothelial growth factor secretion were observed from cells exposed to these three glass fibers, and the copper/zinc containing borate 1605 fibers exhibited the most positive influence. These results indicate that dynamic studies of in vitro bioactivity provide useful information to understand the in vivo response to bioactive borate glasses. - Highlights: • Novel dynamic flow cell culture modules were designed. • Bioactive glass fibers were evaluated for their effects on VEGF secretion. • Borate-based glass fibers stimulate VEGF secretion under dynamic condition. • CuO and ZnO doped borate-based glass fibers stimulate the greatest VEGF release.

  19. Influence of growth conditions on adhesion of yeast Candida spp. and Pichia spp. to stainless steel surfaces.

    Science.gov (United States)

    Tomičić, Ružica; Raspor, Peter

    2017-08-01

    An understanding of adhesion behavior of Candida and Pichia yeast under different environmental conditions is key to the development of effective preventive measures against biofilm-associated infection. Hence in this study we investigated the impact of growth medium and temperature on Candida and Pichia adherence using stainless steel (AISI 304) discs with different degrees of surface roughness (Ra = 25.20-961.9 nm), material typical for the food processing industry as well as medical devices. The adhesion of the yeast strains to stainless steel surfaces grown in Malt Extract broth (MEB) or YPD broth at three temperatures (7 °C, 37 °C, 43 °C for Candida strains and 7 °C, 27 °C, 32 °C for Pichia strains) was assessed by crystal violet staining. The results showed that the nutrient content of medium significantly influenced the quantity of adhered cells by the tested yeasts. Adhesion of C. albicans and C. glabrata on stainless steel surfaces were significantly higher in MEB, whereas for C. parapsilosis and C. krusei it was YPD broth. In the case with P. pijperi and P. membranifaciens, YPD broth was more effective in promoting adhesion than MEB. On the other hand, our data indicated that temperature is a very important factor which considerably affects the adhesion of these yeast. There was also significant difference in cell adhesion on all types of stainless steel surfaces for all tested yeast. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The Arabidopsis Phytocystatin AtCYS5 Enhances Seed Germination and Seedling Growth under Heat Stress Conditions.

    Science.gov (United States)

    Song, Chieun; Kim, Taeyoon; Chung, Woo Sik; Lim, Chae Oh

    2017-08-01

    Phytocystatins (PhyCYSs) are plant-specific proteinaceous inhibitors that are implicated in protein turnover and stress responses. Here, we characterized a PhyCYS from Arabidopsis thaliana , which was designated AtCYS5. RT-qPCR analysis showed that the expression of AtCYS5 in germinating seeds was induced by heat stress (HS) and exogenous abscisic acid (ABA) treatment. Analysis of the expression of the β -glucuronidase reporter gene under the control of the AtCYS5 promoter showed that AtCYS5 expression during seed germination was induced by HS and ABA. Constitutive overexpression of AtCYS5 driven by the cauliflower mosaic virus 35S promoter led to enhanced HS tolerance in transgenic Arabidopsis , which was characterized by higher fresh weight and root length compared to wild-type (WT) and knockout ( cys5 ) plants grown under HS conditions. The HS tolerance of At-CYS5 -overexpressing transgenic plants was associated with increased insensitivity to exogenous ABA during both seed germination and post-germination compared to WT and cys5 . Although no HS elements were identified in the 5'-flanking region of AtCYS5 , canonical ABA-responsive elements (ABREs) were detected. AtCYS5 was upregulated in ABA-treated protoplasts transiently co-expressing this gene and genes encoding bZIP ABRE-binding factors (ABFs and AREB3). In the absence of ABA, ABF1 and ABF3 directly bound to the ABREs in the AtCYS5 promoter, which activated the transcription of this gene in the presence of ABA. These results suggest that an ABA-dependent pathway plays a positive role in the HS-responsive expression of AtCYS5 during seed germination and post-germination growth.

  1. Formation and conversion of oxygen metabolites by Lactococcus lactis subsp lactis ATCC 19435 under different growth conditions

    NARCIS (Netherlands)

    Niel, van E.W.J.; Hofvendahl, K.; Hahn Hagerdal, B.

    2002-01-01

    A semidefined medium based on Casamino Acids allowed Lactococcus lactis ATCC 19435 to grow in the presence of oxygen at a slow rate (0.015 h-1). Accumulation of H2O2 in the culture prevented a higher growth rate. Addition of asparagine to the medium increased the growth rate, whereby H2O2

  2. Effects of feeding frequency on growth, survival rate and body composition in sea bass (Lates calcarifer) juveniles fed a commercial diet under laboratory condition

    OpenAIRE

    Erlinda S. Ganzon-Naret

    2013-01-01

    A 60 day feeding trial was conducted to investigate the effects of different feeding frequencies on the growth, survival rate and body composition of sea bass (Lates calcarifer) juveniles fed commercial diet, reared under laboratory condition. The average initial weight of fish was 4.59 g and its initial total length of 7.11 cm was determined for the conditions factors. Ten fish were stocked in each 12 - 100 L conical fiberglass tanks filled with 90 L seawater at three replicates ...

  3. Influence of culture conditions on growth and protein metabolism in chlorella pyranosides; Influencia de las condiciones de cultivo sobre el crecimiento y metabolismo proteico de chlorella pyrenoidosa

    Energy Technology Data Exchange (ETDEWEB)

    Mazon Matanzo, M P; Fernandez Gonzalez, J; Batuecas Suarez, B

    1981-07-01

    Growth and protein metabolism of Chlorella pyranoside under different conditions of temperature, photo period and CO{sub 2} concentration was studied. The optimum of biomass production was observed at 25 degree centigree, 40.000 ppm of CO{sub 2} in air and a 20 h. light period, followed of 4 h. of darkness. Some variations in free aminoacids content was observed under different conditions but no change did occur in protein. (Author) 68 refs.

  4. Sclerotial biomass and carotenoid yield of Penicillium sp. PT95 under oxidative growth conditions and in the presence of antioxidant ascorbic acid.

    Science.gov (United States)

    Li, X L; Cui, X H; Han, J R

    2006-09-01

    To determine the effect of oxidative stress and exogenous ascorbic acid on sclerotial biomass and carotenoid yield of Penicillium sp. PT95. In this experiment, high oxidative stress was applied by the inclusion of FeSO(4) in the growth medium and exposure to light. Low oxidative stress was applied by omitting iron from the growth medium and by incubation in the dark. Supplementation of exogenous ascorbic acid (as antioxidant) to the basal medium caused a concentration-dependent delay of sclerotial differentiation (up to 48 h), decrease of sclerotial biomass (up to 40%) and reduction of carotenoid yield (up to 91%). On the contrary, the exogenous ascorbic acid also caused a concentration-dependent decrease of lipid peroxidation in colonies of this fungus. Under high oxidative stress growth condition, the sclerotial biomass and carotenoid yield of PT95 strain in each plate culture reached 305 mg and 32.94 microg, which were 1.23 and 3.71 times higher, respectively, than those at low oxidative stress growth condition. These data prompted us to consider that in order to attain higher sclerotial biomass and pigment yield, the strain PT95 should be grown under high oxidative stress and in the absence of antioxidants. These results suggest that strain PT95 may be used for solid-state fermentation of carotenoid production under high oxidative stress growth conditions.

  5. The effects of intermittent exposure to low-pH and low-oxygen conditions on survival and growth of juvenile red abalone

    Science.gov (United States)

    Kim, T. W.; Barry, J. P.; Micheli, F.

    2013-11-01

    Exposure of nearshore animals to hypoxic, low-pH waters upwelled from below the continental shelf and advected near the coast may be stressful to marine organisms and lead to impaired physiological performance. We mimicked upwelling conditions in the laboratory and tested the effect of fluctuating exposure to water with low-pH and/or low-oxygen levels on the mortality and growth of juvenile red abalone (Haliotis rufescens, shell length 5-10 mm). Mortality rates of juvenile abalone exposed to low-pH (7.5, total scale) and low-O2 (40% saturation, mg L-1) conditions for periods of 3 to 6 h every 3-5 days over 2 weeks did not differ from those exposed to control conditions (O2: 100% saturation, 12 mg L-1; pH 8.0). However, when exposure was extended to 24 h, twice over a 15-day period, juveniles experienced 5-20% higher mortality in the low-oxygen treatments compared to control conditions. Growth rates were reduced significantly when juveniles were exposed to low-oxygen and low-pH treatments. Furthermore, individual variation of growth rate increased when juveniles were exposed simultaneously to low-pH and low-O2 conditions. These results indicate that prolonged exposure to low-oxygen levels is detrimental for the survival of red abalone, whereas pH is a crucial factor for their growth. However, the high individual variation in growth rate under low levels of both pH and oxygen suggests that cryptic phenotypic plasticity may promote resistance to prolonged upwelling conditions by a portion of the population.

  6. Influence of filtration and glucose amendment on bacterial growth rate at different tidal conditions in the Minho Estuary River (NW Portugal)

    DEFF Research Database (Denmark)

    Anne, I.; Fidalgo, M. L.; Thosthrup, L.

    2006-01-01

    Bacterioplankton abundance, biomass and growth rates were studied in the Minho Estuary River (NW Portugal). The influence of tidal conditions, glucose amendment, and the filtration process on total bacterial abundance, total and faecal coliforms, as well as faecal streptococci, were evaluated...

  7. Effects of anaerobic growth conditions on biomass accumulation, root morphology, and efficiencies of nutrient uptake and utilization in seedlings of some southern coastal plain pine species

    International Nuclear Information System (INIS)

    Topa, M.A.

    1984-01-01

    Seedlings of pond (Pinus serotina (Michx.)), sand (P. clausa (Engelm.) Sarg.), and loblolly pines (P. taeda L., drought-hardy and wet site seed sources) were grown in a non-circulating, continuously-flowing solution culture under anaerobic or aerobic conditions to determine the effects of anaerobics on overall growth, root morphology and efficiencies of nutrient uptake and utilization. Although shoot growth of the 11-week old loblolly and pond pines was not affected by anaerobic treatment, it did significantly reduce root biomass. Sand pine suffered the largest biomass reduction. Flooding tolerance was positively correlated with specific morphological changes which enhanced root internal aeration. Oxygen transport from shoot to the root in anaerobically-grown loblolly and pond pine seedlings was demonstrated via rhizosphere oxidation experiments. Tissue elemental analyses showed that anaerobic conditions interfered with nutrient absorption and utilization. Short-term 32 p uptake experiments with intact seedlings indicated that net absorption decreased because of the reduction in root biomass, since H 2 PO 4 - influx in the anaerobically-grown seedlings was more than twice that of their aerobic counterparts. Sand pine possessed the physiological but not morphological capacity to increase P uptake under anaerobic growth conditions. Pond and wet-site loblolly pine seedlings maintained root growth, perhaps through enhanced internal root aeration - an advantage in field conditions where the phosphorus supply may be limited or highly localized

  8. Increased nutritional quality of plants for long-duration spaceflight missions through choice of plant variety and manipulation of growth conditions

    Science.gov (United States)

    Cohu, Christopher M.; Lombardi, Elizabeth; Adams, William W.; Demmig-Adams, Barbara

    2014-02-01

    Low levels of radiation during spaceflight increase the incidence of eye damage and consumption of certain carotenoids (especially zeaxanthin), via a whole-food-based diet (rather than from supplements), is recommended to protect human vision against radiation damage. Availability of fresh leafy produce has, furthermore, been identified as desirable for morale during long spaceflight missions. We report that only trace amounts of zeaxanthin are retained post-harvest in leaves grown under conditions conducive to rapid plant growth. We show that growth of plants under cool temperatures and very high light can trigger a greater retention of zeaxanthin, while, however, simultaneously retarding plant growth. We here introduce a novel growth condition—low growth light supplemented with several short daily light pulses of higher intensity—that also triggers zeaxanthin retention, but without causing any growth retardation. Moreover, two plant varieties with different hardiness exhibited a different propensity for zeaxanthin retention. These findings demonstrate that growth light environment and plant variety can be exploited to simultaneously optimize nutritional quality (with respect to zeaxanthin and two other carotenoids important for human vision, lutein and β-carotene) as well as biomass production of leafy greens suitable as bioregenerative systems for long-duration manned spaceflight missions.

  9. Assessment of Salmonella spp. and Escherichia coli O157:H7 growth on lettuce exposed to isothermal and non-isothermal conditions.

    Science.gov (United States)

    de Oliveira Elias, Susana; Noronha, Tiago Baptista; Tondo, Eduardo Cesar

    2018-06-01

    This study aimed to assess the growth of Salmonella and Escherichia coli O157:H7 on lettuce exposed to isothermal and non-isothermal conditions. Pathogens were inoculated on lettuce separately and stored under isothermal condition at 5 °C, 10 °C, 25 °C, 37 °C for both bacteria, at 40 °C for Salmonella and 42 °C for E. coli O157:H7. Growth curves were built by fitting the data to the Baranyi's DMFit, generating R 2 values greater than 0.92 for primary models. Secondary models were fitted with Ratkowsky equations, generating R 2 values higher than 0.91 and RMSE lower than 0.1. Experimental data showed that both bacteria could grow at all temperatures. Also, the growth of both pathogens under non-isothermal conditions was studied simulating temperatures found from harvest to supermarkets in Brazil. Models were analysed by R 2 , RMSE, bias factor (Bf) and accuracy factor (Af). Salmonella and E. coli O157:H7 were able to grow in this temperature profile and the models could predict the behavior of these microorganisms on lettuce under isothermal and non-isothermal conditions. Based on the results, a negligible growth time (ς) was proposed to provide the time which lettuce could be exposed to a specific temperature and do not present an expressive growth of bacteria. The ς was developed based on Baranyi's primary model equation and on growth potential concept. ς is the value of lag phase added of the time necessary to population grow 0.5 log CFU/g. The ς of lettuce exposed to 37 °C was 1.3 h, while at 5 °C was 3.3 days. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Peach water relations, gas exchange, growth and shoot mortality under water deficit in semi-arid weather conditions.

    Science.gov (United States)

    Rahmati, Mitra; Davarynejad, Gholam Hossein; Génard, Michel; Bannayan, Mohammad; Azizi, Majid; Vercambre, Gilles

    2015-01-01

    In this study the sensitivity of peach tree (Prunus persica L.) to three water stress levels from mid-pit hardening until harvest was assessed. Seasonal patterns of shoot and fruit growth, gas exchange (leaf photosynthesis, stomatal conductance and transpiration) as well as carbon (C) storage/mobilization were evaluated in relation to plant water status. A simple C balance model was also developed to investigate sink-source relationship in relation to plant water status at the tree level. The C source was estimated through the leaf area dynamics and leaf photosynthesis rate along the season. The C sink was estimated for maintenance respiration and growth of shoots and fruits. Water stress significantly reduced gas exchange, and fruit, and shoot growth, but increased fruit dry matter concentration. Growth was more affected by water deficit than photosynthesis, and shoot growth was more sensitive to water deficit than fruit growth. Reduction of shoot growth was associated with a decrease of shoot elongation, emergence, and high shoot mortality. Water scarcity affected tree C assimilation due to two interacting factors: (i) reduction in leaf photosynthesis (-23% and -50% under moderate (MS) and severe (SS) water stress compared to low (LS) stress during growth season) and (ii) reduction in total leaf area (-57% and -79% under MS and SS compared to LS at harvest). Our field data analysis suggested a Ψstem threshold of -1.5 MPa below which daily net C gain became negative, i.e. C assimilation became lower than C needed for respiration and growth. Negative C balance under MS and SS associated with decline of trunk carbohydrate reserves--may have led to drought-induced vegetative mortality.

  11. Growth response and nutrient uptake of blue pine (Pinus wallichiana seedlings inoculated with rhizosphere microorganisms under temperate nursery conditions

    Directory of Open Access Journals (Sweden)

    M.A. Ahangar

    2012-11-01

    Full Text Available Microbial inoculants (Trichoderma harzianum, Pseudomonas fluorescens,Laccaria laccata inoculated either individually or in combinationsignificantly improved the growth and biomass of blue pine seedlings. The ECM fungus Laccaria laccata, when inoculated individually, showed significantly higher plant growth, followed by Pseudomonas fluorescens and Trichoderma harzianum. The combined inoculation of rhizosphere microorganisms showed synergistic growth promoting action and proved superior in enhancing the growth of blue pine than individual inoculation. Co-inoculation of L. laccata with P. fluorescens resulted in higher ectomycorrhizal root colonization. Uptake of nutrients (N, P, K was significantly improved by microbial inoculants, tested individually or in combination. Combined inoculation of L. laccata with T. harzianum and P. fluorescens significantly increased in N, P and K contents in blue pine seedlings as compared to control. Acid phosphatase activity in the rhizosphere of blue pine seedlings was also enhanced by these microorganisms. L. laccata exhibited higher acid phosphatase activity followed by P. fluorescens.

  12. The endophytic fungus Piriformospora indica enhances Arabidopsis thaliana growth and modulates Na + /K + homeostasis under salt stress conditions

    KAUST Repository

    Abdelaziz, Mohamed Ewis; Kim, Dongjin; Ali, Shawkat; Fedoroff, Nina V.; Al-Babili, Salim

    2017-01-01

    The mutualistic, endophytic fungus Piriformospora indica has been shown to confer biotic and abiotic stress tolerance to host plants. In this study, we investigated the impact of P. indica on the growth of Arabidopsis plants under normal and salt

  13. [The process of heme synthesis in bone marrow mesenchymal stem cells cultured under fibroblast growth factor bFGF and hypoxic conditions].

    Science.gov (United States)

    Poleshko, A G; Lobanok, E S; Mezhevikina, L M; Fesenko, E E; Volotkovskiĭ, I D

    2014-01-01

    It was demonstrated that fibroblast growth factor bFGF influences the process of heme synthesis, the proliferation activity and viability of bone marrow mesenchymal stem cells in culture under hypoxic conditions. The addition of fibroblast growth factor bFGF (7 ng/ml) to the medium under above conditions led to the accumulation of aminolevulinic acid--an early porphyrin and heme precursor, an increase in CD 71 expression--a transferrin receptor, and also a decrease in porphyrin pigments and heme contents--a late precursor and end products of heme synthesis, respectively. It was found that cultivation of the cells under hypoxic conditions and bFGF is an optimum to maintain high viability and proliferation capacity of the mesenchymal stem cells.

  14. Antimicrobial Effect of 15 Medicinal Plant Species and their Dependency on Climatic Conditions of Growth in Different Geographical and Ecological Areas of Fars Province

    Directory of Open Access Journals (Sweden)

    Abbas Abdollahi

    2012-05-01

    Full Text Available Background: The effects of medicinal plants are variable in different conditions. Here, the antimicrobial effect of 15 medicinal plant species and their dependency on the climatic condition of growth in different geographical and ecological areas of Fars Province were studied. Materials and Methods: In This empirical study, the antimicrobial effect of hydro-alcoholic extract of 15 medicinal plant species was examined against standard bacterial strains comparing to conventional therapeutic antibiotics using disk diffusion assay and serial broth dilution. Results: All Extracts were effective against S.aureus ATCC 25923 growth; also Peganum harmala, Myrtus communis, Mentha pulegium, Mentha spp, and Zataria multiflora extracts were observed to have antimicrobial activity against E.coli ATCC 25922. This antimicrobial activity had partially similar results, comparing to conventional antibioticsConclusion: Medicinal plants produce various amounts of antimicrobial substances under the climatic and ecological conditions of each zone, which must be considered in manufacturing herbal medicines.

  15. The role of phytochrome A and gibberellins in growth under long and short day conditions: Studies in hybrid aspen

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, M.E. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Forest Genetics and Plant Physiology

    2000-07-01

    This thesis addresses questions concerning the regulation of growth and, specifically, the cessation of growth in response to short days in deciduous tree species. The model tree used in the studies was hybrid aspen (Populus tremula L. x P. tremuloides Michx.). We have exploited the possibility of transforming this species to modulate the level of expression of target genes using over-expression and antisense techniques. The target genes in the studies were the photoreceptor phytochrome A (phyA) and gibberellin 20-oxidase (GA 20-oxidase), the latter being a highly regulated enzyme involved in the biosynthesis of gibberellins (GAs). The photoreceptor phyA has been implicated in photoperiodic regulation of growth, while GAs may regulate the physiological response further downstream. The endogenous expression of these genes has been investigated in parallel with studies of various plants with ectopic and reduced levels of expression. The main focus has been on the early stages of induction of growth cessation and its physiological and molecular mechanisms. Studies of hybrid aspen plants with an increased or reduced expression of phyA, show this receptor to mediate the photoperiodic regulation of growth. Plants with ectopic expression could not stop growing despite drastically shortened photoperiods, while the antisense plants showed the reverse phenotype, with a higher sensitivity resulting in earlier cessation of growth. The role of GAs in growth inhibition was also addressed using plants with a reduction in GA levels. These plants showed early cessation of growth and dormancy, and thus an increased sensitivity toward daylength. Conversely, plants with increased rates of GA biosynthesis showed increased growth and stopped growing much later. Furthermore, increases in GA biosynthesis, resulting in high levels of GAs have a major impact on growth. Plants with high GA levels have increased elongation and diameter growth, due to higher rates of cell production in the

  16. Identification of risk conditions for the development of adrenal disorders: how optimized PubMed search strategies makes the difference.

    Science.gov (United States)

    Guaraldi, Federica; Parasiliti-Caprino, Mirko; Goggi, Riccardo; Beccuti, Guglielmo; Grottoli, Silvia; Arvat, Emanuela; Ghizzoni, Lucia; Ghigo, Ezio; Giordano, Roberta; Gori, Davide

    2014-12-01

    The exponential growth of scientific literature available through electronic databases (namely PubMed) has increased the chance of finding interesting articles. At the same time, search has become more complicated, time consuming, and at risk of missing important information. Therefore, optimized strategies have to be adopted to maximize searching impact. The aim of this study was to formulate efficient strings to search PubMed for etiologic associations between adrenal disorders (ADs) and other conditions. A comprehensive list of terms identifying endogenous conditions primarily affecting adrenals was compiled. An ad hoc analysis was performed to find the best way to express each term in order to find the highest number of potentially pertinent articles in PubMed. A predefined number of retrieved abstracts were read to assess their association with ADs' etiology. A more sensitive (providing the largest literature coverage) and a more specific (including only those terms retrieving >40 % of potentially pertinent articles) string were formulated. Various researches were performed to assess strings' ability to identify articles of interest in comparison with non-optimized literature searches. We formulated optimized, ready applicable tools for the identification of the literature assessing etiologic associations in the field of ADs using PubMed, and demonstrated the advantages deriving from their application. Detailed description of the methodological process is also provided, so that this work can easily be translated to other fields of practice.

  17. Instrumenting the Conifers: A Look at Daily Tree Growth and Locally Observed Environmental Conditions Across Four Mountain Sites in the Central Great Basin, USA

    Science.gov (United States)

    Strachan, S.; Biondi, F.; Johnson, B. G.

    2012-12-01

    Tree growth is often used as a proxy for past environmental conditions or as an indicator of developing trends. Reconstructions of drought, precipitation, temperature, and other phenomena derived from tree-growth indices abound in scientific literature aimed at informing policy makers. Observations of tree recruitment or death in treeline populations are frequently tied to climatic fluctuation in cause-effect hypotheses. Very often these hypotheses are based on statistical relationships between annual-to-seasonal tree growth measurements and some environmental parameter measured or modeled off-site. Observation of daily tree growth in conjunction with in-situ environmental measurements at similar timescales takes us one step closer to quantifying the uncertainty in reconstruction or predictive studies. In four separate sites in two different mountain ranges in the central Great Basin, co-located observations of conifer growth activity and local atmospheric and soils conditions have been initiated. Species include Pinus longaeva (Great Basin bristlecone pine), Pinus flexilis (limber pine), Picea engelmannii (Engelmann spruce), Pinus monophylla (singleleaf pinyon pine), Pinus ponderosa (ponderosa pine), Abies concolor (white fir), and Pseudotsuga menziesii (Douglas-fir). Measurements of sub-hourly tree radial length change and sap flow activity are compared with a suite of in-situ observations including air temperature, precipitation, photosynthetically-active radiation (PAR), relative humidity, soil temperature, and soil moisture/water content. Subalpine study site located at 3360 m elevation in the Snake Range, Nevada

  18. Modeling the Growth of Epiphytic Bacteria on Kale Treated by Thermosonication Combined with Slightly Acidic Electrolyzed Water and Stored under Dynamic Temperature Conditions.

    Science.gov (United States)

    Mansur, Ahmad Rois; Oh, Deog-Hwan

    2016-08-01

    The growth of epiphytic bacteria (aerobic mesophilic bacteria or Pseudomonas spp.) on kale was modeled isothermally and validated under dynamic storage temperatures. Each bacterial count on kale stored at isothermal conditions (4 to 25 °C) was recorded. The results show that maximum growth rate (μmax ) of both epiphytic bacteria increased and lag time (λ) decreased with increasing temperature (P 0.97), whereas lower R(2) > 0.86 and R(2) > 0.87 was observed for the λ and Nmax , respectively. The overall predictions of both epiphytic bacterial growths under nonisothermal conditions with temperature abuse of 15 °C agreed with the observed data, whereas those with temperature abuse of 25 °C were greatly overestimated. The appropriate parameter q0 (physiological state of cells), therefore, was adjusted by a trial and error to fit the model. This study demonstrates that the developed model was able to predict accurately epiphytic bacterial growth on kale stored under nonisothermal conditions particularly those with low temperature abuse of 15 °C. © 2016 Institute of Food Technologists®

  19. The influence of prefire tree growth and crown condition on postfire mortality of sugar pine following prescribed fire in Sequoia National Park

    Science.gov (United States)

    Nesmith, Jonathan C. B.; Das, Adrian J.; O'Hara, Kevin L.; van Mantgem, Phillip J.

    2015-01-01

    Tree mortality is a vital component of forest management in the context of prescribed fires; however, few studies have examined the effect of prefire tree health on postfire mortality. This is especially relevant for sugar pine (Pinus lambertiana Douglas), a species experiencing population declines due to a suite of anthropogenic factors. Using data from an old-growth mixed-conifer forest in Sequoia National Park, we evaluated the effects of fire, tree size, prefire radial growth, and crown condition on postfire mortality. Models based only on tree size and measures of fire damage were compared with models that included tree size, fire damage, and prefire tree health (e.g., measures of prefire tree radial growth or crown condition). Immediately following the fire, the inclusion of different metrics of prefire tree health produced variable improvements over the models that included only tree size and measures of fire damage, as models that included measures of crown condition performed better than fire-only models, but models that included measures of prefire radial growth did not perform better. However, 5 years following the fire, sugar pine mortality was best predicted by models that included measures of both fire damage and prefire tree health, specifically, diameter at breast height (DBH, 1.37 m), crown scorch, 30-year mean growth, and the number of sharp declines in growth over a 30-year period. This suggests that factors that influence prefire tree health (e.g., drought, competition, pathogens, etc.) may partially determine postfire mortality, especially when accounting for delayed mortality following fire.

  20. Validity limits in J-resistance curve determination: A computational approach to ductile crack growth under large-scale yielding conditions. Volume 2

    International Nuclear Information System (INIS)

    Shih, C.F.; Xia, L.; Hutchinson, J.W.

    1995-02-01

    In this report, Volume 2, Mode I crack initiation and growth under plane strain conditions in tough metals are computed using an elastic/plastic continuum model which accounts for void growth and coalescence ahead of the crack tip. The material parameters include the stress-strain properties, along with the parameters characterizing the spacing and volume fraction of voids in material elements lying in the plane of the crack. For a given set of these parameters and a specific specimen, or component, subject to a specific loading, relationships among load, load-line displacement and crack advance can be computed with no restrictions on the extent of plastic deformation. Similarly, there is no limit on crack advance, except that it must take place on the symmetry plane ahead of the initial crack. Suitably defined measures of crack tip loading intensity, such as those based on the J-integral, can also be computed, thereby directly generating crack growth resistance curves. In this report, the model is applied to five specimen geometries which are known to give rise to significantly different crack tip constraints and crack growth resistance behaviors. Computed results are compared with sets of experimental data for two tough steels for four of the specimen types. Details of the load, displacement and crack growth histories are accurately reproduced, even when extensive crack growth takes place under conditions of fully plastic yielding. A description of material resistance to crack initiation and subsequent growth is essential for assessing structural integrity such as nuclear pressure vessels and piping

  1. Effect of environmental and cultural conditions on medium pH and explant growth performance of Douglas-fir ( Pseudotsuga menziesii) shoot cultures

    OpenAIRE

    Chen, Chien-Chih; Bates, Rick; Carlson, John

    2015-01-01

    The medium pH level of plant tissue cultures has been shown to be essential to many aspects of explant development and growth. Sensitivity or tolerance of medium pH change in vitro varies according to specific requirements of individual species. The objectives of this study are to 1) determine medium pH change over time in storage conditions and with presence of explants, 2) evaluate the effects of medium pH change on explant growth performance and 3) assess the effects of adding a pH stabili...

  2. Evaluation of growth and gas exchange rates of two local saudi wheat cultivars grown under heat stress conditions

    International Nuclear Information System (INIS)

    Boutraa, T.; Akhkha, A.; Shoaibi, A.K.

    2015-01-01

    The present study investigated the effects of three temperature regimes, low (20 degree C), moderate (25 degree C) and high (30 degree C), on growth and physiological parameters of two local Saudi wheat (Triticum durum) cultivars, Hab-Ahmar and Algaimi. Plants were grown under controlled environment in growth chambers. After four weeks plants were harvested and the following growth parameters were measured; plant height, number of tillers, leaf area, root length, fresh and dry weight. Physiological traits include chlorophyll content, photosynthesis rates, stomatal conductance, dark respiration and chlorophyll fluorescence parameters; Fo, Fm and Fv/Fm. In cultivar Hab-Ahmar, moderate and high temperatures caused significant decrease in most growth and physiological parameters such as plant height, number of tillers, leaf area, fresh and dry weight, chlorophyll content, photosynthesis rates, stomatal conductance, dark respiration and the maximum quantum yield of photosystem II (Fv/Fm). In contrast, cv. Algaimi was shown to be more thermotolerant to moderate and high temperatures, with the exception of some growth parameters that were decreased. Unlike cultivar Hab-Ahmar, cultivar Algaimi had an increased rate of dark respiration when temperature was high (30 degree C). Stomatal behavior is shown to be positively correlated with the rates of photosynthesis in both cultivars; however, in cultivar Hab-Ahmar such correlation decreased as temperature increased. (author)

  3. Influence of seed priming and nitrogen application on the growth and development of maize seedlings in saline conditions

    International Nuclear Information System (INIS)

    Cao, D.; Zhang, Y.; Zhang, Y.; Guan, B.

    2018-01-01

    Seed priming and nitrogen application can promote plant tolerance and resistance to salt stress. To explore the combined effects of these two factors on the growth of salt-stressed seedlings, four treatments (priming + nitrogen application, PN; priming + no nitrogen application, P; unprimed + nitrogen application, UPN; and control treatment unprimed + no nitrogen application, UP) were applied to evaluate the responses of plant morphology, antioxidase systems, physiological and biochemical parameters of the maize seedlings under different concentrations of salt stress (0, 100, 200, and 300 mM). The results indicated that under salt stress, the priming treatment facilitated the growth of seedlings of root and stems, increased the amount of osmoregulatory substances, and enhanced the antioxidase activity and resistance of the maize seedlings. After nitrogen application during the maize growth stage, the growth of young leaves was greatly promoted along with an increase in the soluble protein and chlorophyll content. The combination of seed priming and nitrogen application significantly improved the plant growth, antioxidase activities and physiological and biochemical parameters. (author)

  4. Attaining the canopy in dry and moist tropical forests: strong differences in tree growth trajectories reflect variation in growing conditions.

    Science.gov (United States)

    Brienen, Roel J W; Zuidema, Pieter A; Martínez-Ramos, Miguel

    2010-06-01

    Availability of light and water differs between tropical moist and dry forests, with typically higher understorey light levels and lower water availability in the latter. Therefore, growth trajectories of juvenile trees--those that have not attained the canopy--are likely governed by temporal fluctuations in light availability in moist forests (suppressions and releases), and by spatial heterogeneity in water availability in dry forests. In this study, we compared juvenile growth trajectories of Cedrela odorata in a dry (Mexico) and a moist forest (Bolivia) using tree rings. We tested the following specific hypotheses: (1) moist forest juveniles show more and longer suppressions, and more and stronger releases; (2) moist forest juveniles exhibit wider variation in canopy accession pattern, i.e. the typical growth trajectory to the canopy; (3) growth variation among dry forest juveniles persists over longer time due to spatial heterogeneity in water availability. As expected, the proportion of suppressed juveniles was higher in moist than in dry forest (72 vs. 17%). Moist forest suppressions also lasted longer (9 vs. 5 years). The proportion of juveniles that experienced releases in moist forest (76%) was higher than in dry forest (41%), and releases in moist forests were much stronger. Trees in the moist forest also had a wider variation in canopy accession patterns compared to the dry forest. Our results also showed that growth variation among juvenile trees persisted over substantially longer periods of time in dry forest (>64 years) compared to moist forest (12 years), most probably because of larger persistent spatial variation in water availability. Our results suggest that periodic increases in light availability are more important for attaining the canopy in moist forests, and that spatial heterogeneity in water availability governs long-term tree growth in dry forests.

  5. Responses of Tree Growths to Tree Size, Competition, and Topographic Conditions in Sierra Nevada Forests Using Bi-temporal Airborne LiDAR Data

    Science.gov (United States)

    Ma, Q.; Su, Y.; Tao, S.; Guo, Q.

    2016-12-01

    Trees in the Sierra Nevada (SN) forests are experiencing rapid changes due to human disturbances and climatic changes. An improved monitoring of tree growth and understanding of how tree growth responses to different impact factors, such as tree competition, forest density, topographic and hydrologic conditions, are urgently needed in tree growth modeling. Traditional tree growth modeling mainly relied on field survey, which was highly time-consuming and labor-intensive. Airborne Light detection and ranging System (ALS) is increasingly used in forest survey, due to its high efficiency and accuracy in three-dimensional tree structure delineation and terrain characterization. This study successfully detected individual tree growth in height (ΔH), crown area (ΔA), and crown volume (ΔV) over a five-year period (2007-2012) using bi-temporal ALS data in two conifer forest areas in SN. We further analyzed their responses to original tree size, competition indices, forest structure indices, and topographic environmental parameters at individual tree and forest stand scales. Our results indicated ΔH was strongly sensitive to topographic wetness index; whereas ΔA and ΔV were highly responsive to forest density and original tree sizes. These ALS based findings in ΔH were consistent with field measurements. Our study demonstrated the promising potential of using bi-temporal ALS data in forest growth measurements and analysis. A more comprehensive study over a longer temporal period and a wider range of forest stands would give better insights into tree growth in the SN, and provide useful guides for forest growth monitoring, modeling, and management.

  6. Effect of Salinity on Growth and Physiological Parameters of Four Olive (OleaeuropaeaL. Cultivars underGreenhouse Conditions

    Directory of Open Access Journals (Sweden)

    Farzaneh Olyaei

    2017-02-01

    Full Text Available Introduction: Salinity is a common abiotic stress that seriously affects crop production around the world, particularly in arid and semi-arid regions.The deleterious effects of salinity on plant growth are associated with low osmotic potential of soil solution (water stress, nutritional imbalance, specific ion effect (salt stress, or a combination of these factors. Olive is one of the most important fruit crops in Iran and the world. Despite olive has been classified as moderately salt tolerant plant, poor quality of irrigation water in association with salt build-up soils has reduced the yields, especially in arid and semi-arid regions of Iran. The tolerance of the olive to salt is to a great extent depends on the cultivar. Selecting salinity-resistant cultivars is one of the most important strategies used for mitigating salinity effects on olive. Therefore, this study was performed to assess the salt tolerance of four olive cultivars under greenhouse condition. Materials and Methods: For this purpose, one-year-old rooted cuttings of Iranian olive cultivars (‘Dakal’, ‘Shiraz’, ‘Zard’ and non-Iranian cultivar ‘Amigdal’ were grown in the research greenhouse of Agricultural College, Isfahan University of Technology of Iran. Plants were grown in plastic pots. The pots were 180 mm in diameter and 20 mm in depth with volume of 7 L. The minimum and maximum temperatures during the experiment period were 19 and 35˚C, respectively. After sticking the cuttings, the pots with uniform plants were subjected to the treatment with 0 (control, 100, 150 or 200 mMNaCl. The electrical conductivities of these solutions were 0.003, 10.52, 15.43 and 19.55 dS m-1, respectively. To avoid osmotic shock, the NaCl concentration was gradually increased. The layout was a 4×4 factorial experiment based oncompletely randomized design, with four replications. The experimental measurements were carried out three months after beginning the salt treatments

  7. Can biochar be used as a seed coating to improve native plant germination and growth in arid conditions?

    Science.gov (United States)

    Mary I. Williams; R. Kasten Dumroese; Deborah S. Page-Dumroese; Stuart P. Hardegree

    2016-01-01

    Direct seeding is a common large-scale restoration practice for revegetating arid and semi-arid lands, but success can be limited by moisture and temperature. Seed coating technologies that use biochar may have the potential to overcome moisture and temperature limitations on native plant germination and growth. Biochar is a popular agronomic tool for improving soil...

  8. Growth and sporulation of Bacillus cereus ATCC 14579 under defined conditions: temporal expression of genes for key sigma factors

    NARCIS (Netherlands)

    Vries, de Y.P.; Hornstra, L.M.; Vos, de W.M.; Abee, T.

    2004-01-01

    An airlift fermentor system allowing precise regulation of pH and aeration combined with a chemically defined medium was used to study growth and sporulation of Bacillus cereus ATCC 14579. Sporulation was complete and synchronous. Expression of sigA, sigB, sigF, and sigG was monitored with real-time

  9. Quantifying the effects of land conditions on rice growth : a case study in the Ebro Delta (Spain) using remote sensing

    NARCIS (Netherlands)

    Casanova, D.

    1998-01-01

    This thesis represents detailed research on the "rice-soils-weather" system of the Ebro Delta (Spain) providing knowledge on how temperature, radiation, soil properties and farm management determine rice growth. After an introductory chapter, the findings are developed step-by-step. (i)

  10. Development of silvicultural systems for maintaining old-growth conditions in the temperate rainforest of southeast Alaska.

    Science.gov (United States)

    Michael H. McClellan

    2004-01-01

    In the old-growth temperate rainforests of southeast Alaska, concerns over clearcutting effects on habitat, visual quality, slope stability, and biodiversity have created a demand for the use of other silvicultural systems. The forest vegetation and animal taxa of southeast Alaska appear to be well adapted to frequent, widespread, small-scale disturbance, suggesting...

  11. Effect of food type and concentration on growth and fatty acid composition of early larvae of the anchovy (Engraulis encrasicolus) reared under laboratory conditions

    KAUST Repository

    Garrido, Susana

    2012-12-01

    Experiments were conducted during the summer of 2008 and 2009 to study the growth of early post yolk-sac European anchovy (Engraulis encrasicolus, Linnaeus, 1758) larvae reared under different food regimes. The fatty acid composition was used to assess nutritional condition of the larvae. Prey items used in the experiments were Gymnodinium sanguineum, Brachionus plicatilis and nauplii of the copepods Acartia grani and Euterpina acutifrons. Food type and concentration affected the growth of the larvae. Mixed diets composed of rotifers and copepod nauplii at high concentration resulted in higher anchovy larvae growth rates in comparison with single-prey diets using either rotifers or copepod nauplii. The addition of the dinoflagellate G. sanguineum (25-50cellsml -1) to the prey offered did not enhance significantly larval growth. Highest growth rates of anchovy larvae (0.28mmd -1) were obtained using high concentrations of a mixed diet, particularly the combination of rotifers and A. grani nauplii. Fatty acid composition at hatch was similar to the composition observed in the field, but during larvae ontogeny there was a marked decrease in the contribution of polyunsaturated fatty acids such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Such difference reflects the high requirements of these PUFA for larvae development, and suggests that the food offered failed to fulfill the larvae nutritional requirements. The growth rates obtained in our experiments were, overall, in the lower range of those observed in natural conditions. Taking into considerations the fact that larvae in the field are expected to encounter lower prey concentrations, we discuss the reasons for such disagreement. © 2012 Elsevier B.V.

  12. Effect of food type and concentration on growth and fatty acid composition of early larvae of the anchovy (Engraulis encrasicolus) reared under laboratory conditions

    KAUST Repository

    Garrido, Susana; Saiz, Enric; Peters, Janna L.; Ré , Pedrobarcia; Á lvarez, Paula; Cotano, Unai; Herrero, D. L.; de Murguí a, Amalia Martí nez; Irigoien, Xabier

    2012-01-01

    Experiments were conducted during the summer of 2008 and 2009 to study the growth of early post yolk-sac European anchovy (Engraulis encrasicolus, Linnaeus, 1758) larvae reared under different food regimes. The fatty acid composition was used to assess nutritional condition of the larvae. Prey items used in the experiments were Gymnodinium sanguineum, Brachionus plicatilis and nauplii of the copepods Acartia grani and Euterpina acutifrons. Food type and concentration affected the growth of the larvae. Mixed diets composed of rotifers and copepod nauplii at high concentration resulted in higher anchovy larvae growth rates in comparison with single-prey diets using either rotifers or copepod nauplii. The addition of the dinoflagellate G. sanguineum (25-50cellsml -1) to the prey offered did not enhance significantly larval growth. Highest growth rates of anchovy larvae (0.28mmd -1) were obtained using high concentrations of a mixed diet, particularly the combination of rotifers and A. grani nauplii. Fatty acid composition at hatch was similar to the composition observed in the field, but during larvae ontogeny there was a marked decrease in the contribution of polyunsaturated fatty acids such as EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Such difference reflects the high requirements of these PUFA for larvae development, and suggests that the food offered failed to fulfill the larvae nutritional requirements. The growth rates obtained in our experiments were, overall, in the lower range of those observed in natural conditions. Taking into considerations the fact that larvae in the field are expected to encounter lower prey concentrations, we discuss the reasons for such disagreement. © 2012 Elsevier B.V.

  13. Near-Real-Time Monitoring and Reporting of Crop Growth Condition and Harvest Status Using an Integrated Optical and Radar Approach at the National-Scale in Canada

    Science.gov (United States)

    Shang, J.

    2015-12-01

    There has been an increasing need to have accurate and spatially detailed information on crop growth condition and harvest status over Canada's agricultural land so that the impacts of environmental conditions, market supply and demand, and transportation network limitations on crop production can be understood fully and acted upon in a timely manner. Presently, Canada doesn't have a national dataset that can provide near-real-time geospatial information on crop growth stage and harvest systematically so that reporting on risk events can be linked directly to the grain supply chain and crop production fluctuations. The intent of this study is to develop an integrated approach using Earth observation (EO) technology to provide a consistent, comprehensive picture of crop growth cycles (growth conditions and stages) and agricultural management activities (field preparation for seeding, harvest, and residue management). Integration of the optical and microwave satellite remote sensing technologies is imperative for robust methodology development and eventually for operational implementation. Particularly, the current synthetic aperture radar (SAR) system Radarsat-2 and to be launched Radarsat Constellation Mission (RCM) are unique EO resources to Canada. Incorporating these Canadian SAR resources with international SAR missions such as the Cosmesky-Med and TerraSAR, could be of great potential for developing change detection technologies particularly useful for monitoring harvest as well as other types of agricultural management events. The study revealed that radar and multi-scale (30m and 250m) optical satellite data can directly detect or infer 1) seeding date, 2) crop growth stages and gross primary productivity (GPP), and 3) harvest progress. Operational prototypes for providing growing-season information at the crop-specific level will be developed across the Canadian agricultural land base.

  14. Impact of growth and annealing conditions on the parameters of Ge/Si(001) relaxed layers grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Yurasov, D. V., E-mail: Inquisitor@ipm.sci-nnov.ru [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Bobrov, A. I. [Lobachevsky State University of Nizhny Novgorod (Russian Federation); Daniltsev, V. M.; Novikov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Pavlov, D. A. [Lobachevsky State University of Nizhny Novgorod (Russian Federation); Skorokhodov, E. V.; Shaleev, M. V.; Yunin, P. A. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2015-11-15

    Influence of the Ge layer thickness and annealing conditions on the parameters of relaxed Ge/Si(001) layers grown by molecular beam epitaxy via two-stage growth is investigated. The dependences of the threading dislocation density and surface roughness on the Ge layer thickness, annealing temperature and time, and the presence of a hydrogen atmosphere are obtained. As a result of optimization of the growth and annealing conditions, relaxed Ge/Si(001) layers which are thinner than 1 μm with a low threading dislocation density on the order of 10{sup 7} cm{sup –2} and a root mean square roughness of less than 1 nm are obtained.

  15. The influence of ppb levels of chloride impurities on the stress corrosion crack growth behaviour of low-alloy steels under simulated boiling water reactor conditions

    International Nuclear Information System (INIS)

    Seifert, H.P.; Ritter, S.

    2016-01-01

    Highlights: • Chloride effects on SCC crack growth in RPV steels under boiling water reactor conditions. • ppb-levels of chloride may result in fast SCC in normal water chemistry environment. • Much higher chloride tolerance for SCC in hydrogen water chemistry environment. • Potential long-term (memory) effects after severe and prolonged temporary chloride transients. - Abstract: The effect of chloride on the stress corrosion crack (SCC) growth behaviour in low-alloy reactor pressure vessel steels was evaluated under simulated boiling water reactor conditions. In normal water chemistry environment, ppb-levels of chloride may result in fast SCC after rather short incubation periods of few hours. After moderate and short-term chloride transients, the SCC crack growth rates return to the same very low high-purity water values within few 100 h. Potential long-term (memory) effects on SCC crack growth cannot be excluded after severe and prolonged chloride transients. The chloride tolerance for SCC in hydrogen water chemistry environment is much higher.

  16. Integrated use of plant growth promoting rhizobacteria, biogas slurry and chemical nitrogen for sustainable production of maize under salt-affected conditions

    International Nuclear Information System (INIS)

    Ahmad, M.; Jamil, M.; Akhtar, F.U.Z.

    2014-01-01

    Salinity is one of the most critical constraints hampering agricultural production throughout the world, including Pakistan. Some plant growth promoting rhizobacteria (PGPR) have the ability to reduce the deleterious effect of salinity on plants due to the presence of ACC-deaminase enzyme along with some other mechanisms. The integrated use of organic, chemical and biofertilizers can reduce dependence on expensive chemical inputs. To sustain high crop yields without deterioration of soil fertility, it is important to work out optimal combination of chemical and biofertilizers, and manures in the cropping system. A pot trial was conducted to study the effect of integrated use of PGPR, chemical nitrogen, and biogas slurry for sustainable production of maize under salt-stressed conditions and for good soil health. Results showed that sole application of PGPR, chemical nitrogen and biogas slurry enhanced maize growth but their combined application was more effective. Maximum improvement in maize growth, yield, ionic concentration in leaves and nutrient concentration in grains was observed in the treatment where PGPR and biogas slurry was used in the presence of 100% recommended nitrogen as chemical fertilizer. It also improved the soil pH, ECe, and available N, P and K contents. It is concluded that integrated use of PGPR, biogas slurry and chemical nitrogen not only enhanced maize growth, yield and quality but also improved soil health. So, it may be evaluated under field conditions to get sustained yield of maize from salt-affected soils. (author)

  17. The effect of plant growth-promoting rhizobacteria on asparagus seedlings and germinating seeds subjected to water stress under greenhouse conditions.

    Science.gov (United States)

    Liddycoat, Scott M; Greenberg, Bruce M; Wolyn, David J

    2009-04-01

    Plant growth-promoting rhizobacteria (PGPR) can have positive effects on vigour and productivity, especially under stress conditions. In asparagus (Asparagus officinalis L.) field culture, seeds are planted in high-density nurseries, and 1-year-old crowns are transplanted to production fields. Performance can be negatively affected by water stress, transplant shock, and disease pressure on wounded roots. PGPR inoculation has the potential to alleviate some of the stresses incurred in the production system. In this study, the effects of PGPR (Pseudomonas spp.) treatment were determined on 3-week-old greenhouse-grown seedlings and germinating seeds of 2 asparagus cultivars. The pots were irrigated to a predetermined level that resulted in optimum growth or the plants were subjected to drought or flooding stress for 8 weeks. The cultivars responded differently to PGPR: single inoculations of seedlings enhanced growth of 'Guelph Millennium' under optimum conditions and 'Jersey Giant' seedlings under drought stress. Seed inoculations with PGPR resulted in a positive response only for 'Guelph Millennium', for which both single or multiple inoculations enhanced plant growth under drought stress.

  18. Organizing effects of adverse early-life condition on body mass, compensatory growth and reproduction : experimental studies in rock pigeons

    NARCIS (Netherlands)

    Hsu, Bin-Yan; Dijkstra, Cor; Groothuis, Ton G. G.

    Early-life food conditions can have profound impact on adult behavioural performance. In song birds, early-life food conditions affect adult physiology and cognitive performance such as song learning and spatial learning. However, effects on reproductive behaviour other than song, such as visual

  19. Effects of tungsten and titanium oxide nanoparticles on the diazotrophic growth and metals acquisition by Azotobacter vinelandii under molybdenum limiting condition.

    Science.gov (United States)

    Allard, Patrick; Darnajoux, Romain; Phalyvong, Karine; Bellenger, Jean-Philippe

    2013-02-19

    The acquisition of essential metals, such as the metal cofactors (molybdenum (Mo) and iron (Fe)) of the nitrogenase, the enzyme responsible for the reduction of dinitrogen (N(2)) to ammonium, is critical to N(2) fixing bacteria in soil. The release of metal nanoparticles (MNPs) to the environment could be detrimental to N(2) fixing bacteria by introducing a new source of toxic metals and by interfering with the acquisition of essential metals such as Mo. Since Mo has been reported to limit nonsymbiotic N(2) fixation in many ecosystems from tropical to cold temperate, this question is particularly acute in the context of Mo limitation. Using a combination of microbiology and analytical chemistry techniques, we have evaluated the effect of titanium (Ti) and tungsten (W) oxide nanoparticles on the diazotrophic growth and metals acquisition in pure culture of the ubiquitous N(2) fixing bacterium Azotobacter vinelandii under Mo replete and Mo limiting conditions. We