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Sample records for address heat tolerance

  1. Physiological and proteomic approaches to address heat tolerance during anthesis in rice (Oryza sativa L.).

    Science.gov (United States)

    Jagadish, S V K; Muthurajan, R; Oane, R; Wheeler, T R; Heuer, S; Bennett, J; Craufurd, P Q

    2010-01-01

    Episodes of high temperature at anthesis, which in rice is the most sensitive stage to temperature, are expected to occur more frequently in future climates. The morphology of the reproductive organs and pollen number, and changes in anther protein expression, were studied in response to high temperature at anthesis in three rice (Oryza sativa L.) genotypes. Plants were exposed to 6 h of high (38 degrees C) and control (29 degrees C) temperature at anthesis and spikelets collected for morphological and proteomic analysis. Moroberekan was the most heat-sensitive genotype (18% spikelet fertility at 38 degrees C), while IR64 (48%) and N22 (71%) were moderately and highly heat tolerant, respectively. There were significant differences among the genotypes in anther length and width, apical and basal pore lengths, apical pore area, and stigma and pistil length. Temperature also affected some of these traits, increasing anther pore size and reducing stigma length. Nonetheless, variation in the number of pollen on the stigma could not be related to measured morphological traits. Variation in spikelet fertility was highly correlated (r=0.97, n=6) with the proportion of spikelets with > or = 20 germinated pollen grains on the stigma. A 2D-gel electrophoresis showed 46 protein spots changing in abundance, of which 13 differentially expressed protein spots were analysed by MS/MALDI-TOF. A cold and a heat shock protein were found significantly up-regulated in N22, and this may have contributed to the greater heat tolerance of N22. The role of differentially expressed proteins and morphology during anther dehiscence and pollination in shaping heat tolerance and susceptibility is discussed.

  2. Heat tolerance in wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari

    As a consequence of global climate change, heat stress together with other abiotic stresses will remain an important determinant of future food security. Wheat (Triticum aestivum L.) is the third most important crop of the world feeding one third of the world population. Being a crop of temperate...... climate, wheat is sensitive to heat stress. We need to understand how our crops will perform in these changing climatic conditions and how we can develop varieties, which are more tolerant. The PhD study focussed on understanding heat tolerance in wheat with a combined approach of plant physiology...... for physiological traits that may confer better adaptation to changing climatic conditions. Eventually, combining all the identified “good genes” may aid in developing stress tolerant cultivars to overcome environmental constraints and thereby, meet the increasing demand of future food security....

  3. Fault-Tolerant Heat Exchanger

    Science.gov (United States)

    Izenson, Michael G.; Crowley, Christopher J.

    2005-01-01

    A compact, lightweight heat exchanger has been designed to be fault-tolerant in the sense that a single-point leak would not cause mixing of heat-transfer fluids. This particular heat exchanger is intended to be part of the temperature-regulation system for habitable modules of the International Space Station and to function with water and ammonia as the heat-transfer fluids. The basic fault-tolerant design is adaptable to other heat-transfer fluids and heat exchangers for applications in which mixing of heat-transfer fluids would pose toxic, explosive, or other hazards: Examples could include fuel/air heat exchangers for thermal management on aircraft, process heat exchangers in the cryogenic industry, and heat exchangers used in chemical processing. The reason this heat exchanger can tolerate a single-point leak is that the heat-transfer fluids are everywhere separated by a vented volume and at least two seals. The combination of fault tolerance, compactness, and light weight is implemented in a unique heat-exchanger core configuration: Each fluid passage is entirely surrounded by a vented region bridged by solid structures through which heat is conducted between the fluids. Precise, proprietary fabrication techniques make it possible to manufacture the vented regions and heat-conducting structures with very small dimensions to obtain a very large coefficient of heat transfer between the two fluids. A large heat-transfer coefficient favors compact design by making it possible to use a relatively small core for a given heat-transfer rate. Calculations and experiments have shown that in most respects, the fault-tolerant heat exchanger can be expected to equal or exceed the performance of the non-fault-tolerant heat exchanger that it is intended to supplant (see table). The only significant disadvantages are a slight weight penalty and a small decrease in the mass-specific heat transfer.

  4. Heat tolerance in wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari

    As a consequence of global climate change, heat stress together with other abiotic stresses will remain an important determinant of future food security. Wheat (Triticum aestivum L.) is the third most important crop of the world feeding one third of the world population. Being a crop of temperate.......9% in the third screening with 41 selected cultivars. The Fv/Fm was influenced by heat stress and the difference between the cultivars appeared only during the heat stress. Further analysis of other chlorophyll fluorescence parameters showed similar or higher GD, but they did not reveal the genetic difference....... The correlation of the cultivar response in intact plant versus detached leaf was low. Overall, the result suggests that selection of cultivars by detached leaves may operate for different genetic factors than in intact plants. In the third study, the previously selected high and low groups of cultivars (from...

  5. Morphological characterization and evaluation of heat tolerance ...

    African Journals Online (AJOL)

    Morphological characterization and evaluation of heat tolerance traits in Nigerian goat breeds. M Wheto, BM Ilori, AJ Sanda, MA Adeleke, SO Durosaro, AS Adenaike, AO Adebambo, CON Ikeobi, OM Onagbesan, MO Ozoje, OA Adebambo ...

  6. Breeding for plant heat tolerance at vegetative and reproductive stages.

    Science.gov (United States)

    Driedonks, Nicky; Rieu, Ivo; Vriezen, Wim H

    2016-06-01

    Thermotolerant crop research. Global warming has become a serious worldwide threat. High temperature is a major environmental factor limiting crop productivity. Current adaptations to high temperature via alterations to technical and management systems are insufficient to sustain yield. For this reason, breeding for heat-tolerant crops is in high demand. This review provides an overview of the effects of high temperature on plant physiology, fertility and crop yield and discusses the strategies for breeding heat-tolerant cultivars. Generating thermotolerant crops seems to be a challenging task as heat sensitivity is highly variable across developmental stages and processes. In response to heat, plants trigger a cascade of events, switching on numerous genes. Although breeding has made substantial advances in developing heat-tolerant lines, the genetic basis and diversity of heat tolerance in plants remain largely unknown. The development of new varieties is expensive and time-consuming, and knowledge of heat tolerance mechanisms would aid the design of strategies to screen germplasm for heat tolerance traits. However, gains in heat tolerance are limited by the often narrow genetic diversity. Exploration and use of wild relatives and landraces in breeding can increase useful genetic diversity in current crops. Due to the complex nature of plant heat tolerance and its immediate global concern, it is essential to face this breeding challenge in a multidisciplinary holistic approach involving governmental agencies, private companies and academic institutions.

  7. Inheritance and Heritability of Heat Tolerance in Several Sorghum ...

    African Journals Online (AJOL)

    Four sorghum parental lines, RTx430, BTx3197, RTx7000, and B35 and their F1 and reciprocals, and F2 progenies were evaluated during their reproductive phases to access the genetic basis of heat tolerance. Heat tolerance was measured under field and greenhouse conditions at College Station, Texas during 1990.

  8. Desiccation and heat tolerance of Enterobacter sakazakii.

    Science.gov (United States)

    Breeuwer, P; Lardeau, A; Peterz, M; Joosten, H M

    2003-01-01

    Enterobacter sakazakii is an opportunistic pathogen which has been isolated at low levels from powdered infant formulas. This study was performed to demonstrate that Ent. sakazakii is not particularly thermotolerant, but can adapt to osmotic and dry stress. We determined the heat, osmotic and dry stress resistance of Ent. sakazakii. The D-value at 58 degrees C ranged from 0.39 to 0.60 min, which is comparable with that of other Enterobacteriaceae, but much lower than reported previously (Nazarowec-White and Farber 1997, Letters in Applied Microbiology 24: 9-13). However, stationary phase Ent. sakazakii cells were found to be more resistant to osmotic and dry stress than Escherichia coli, Salmonella and other strains of Enterobacteriaceae tested. Further analysis indicated that the dry resistance is most likely linked to accumulation of trehalose in the cells. The high tolerance to desiccation provides a competitive advantage for Ent. sakazakii in dry environments, as found in milk powder factories, and thereby increases the risk of postpasteurization contamination of the finished product. Understanding of the physiology and survival strategies of Ent. sakazakii is an important step in the efforts to eliminate this bacterium from the critical food production environments.

  9. Urban physiology: city ants possess high heat tolerance.

    Directory of Open Access Journals (Sweden)

    Michael J Angilletta

    Full Text Available Urbanization has caused regional increases in temperature that exceed those measured on a global scale, leading to urban heat islands as much as 12 degrees C hotter than their surroundings. Optimality models predict ectotherms in urban areas should tolerate heat better and cold worse than ectotherms in rural areas. We tested these predications by measuring heat and cold tolerances of leaf-cutter ants from South America's largest city (São Paulo, Brazil. Specifically, we compared thermal tolerances of ants from inside and outside of the city. Knock-down resistance and chill-coma recovery were used as indicators of heat and cold tolerances, respectively. Ants from within the city took 20% longer to lose mobility at 42 degrees C than ants from outside the city. Interestingly, greater heat tolerance came at no obvious expense of cold tolerance; hence, our observations only partially support current theory. Our results indicate that thermal tolerances of some organisms can respond to rapid changes in climate. Predictive models should account for acclimatory and evolutionary responses during climate change.

  10. Screening of cotton (gossypium hirsutum l.) genotypes for heat tolerance

    International Nuclear Information System (INIS)

    Abro, S.; Khan, M.A.; Sial, M.A.

    2015-01-01

    Cotton yield is highly affected due to biotic (diseases and pests) and abiotic (heat, dought and salinity) Stresses. Among them, high temperature is the main environmental constraint which adversely reduces cotton yield and quality. High temperature above 36 degree C affects plant growth and development especially during reproductive phase. Present studies were carried out to assess the tolerance of fifty-eight newly evolved cotton genotypes to heat stresses, based on agronomic and physiological characteristics. The genotypes were screened in field conditions under two temperature regimes. The studies were conducted at experimental farm of Nuclear Institute of Agriculture, Tando Jam, Pakistan. The results showed that March sown crop experienced high temperature (i.e. > 44 degree C in May and June), which significantly affected crop growth and productivity. The genotypes were identified as heat-tolerant on the basis of relative cell injury percentage (RCI %), heat susceptibility index (HSI) values, boll retention and seed cotton yield (kg/ha). RCI level in cotton genotypes ranged from 39.0 to 86.0%. Out of 58, seventeen genotypes (viz.NIA-80, NIA-81, NIA-83, NIA-84, NIA-M-30, NIA-M31, NIA-HM-48, NIA-HM-327, NIA-H-32, NIA-HM-2-1, NIA-Bt1, NIA-Bt2, NIA-Perkh, CRIS-342, CRIS-134, NIAB-111 and check variety Sadori indicated high level of heat tolerance at both (heat-stressed and non-stressed) temperature regimes; as shown the lowest relative injury level and relatively heat resistant index (HSI<1) values. Such genotypes could be used as heattolerant genotypes under heat-stressed environments. (author)

  11. Male Parent Plays More Important Role in Heat Tolerance in Three-Line Hybrid Rice

    Directory of Open Access Journals (Sweden)

    Fu Guan-fu

    2015-05-01

    Full Text Available Ten F1 combinations with their male and female parents were employed to evaluate their heat tolerance during the flowering and early grain filling stages. The rice plants were subjected to heat stress (39 °C–43 °C for 1–15 d during flowering. Based on the heat stress index, heat tolerance was only observed in the F1 combinations H2 (K22A × R207, H3 (Bobai A × R207 and H4 (Bobai A × Minghui 63, whereas the others received above 0.5000 of heat stress index. Both parents of the tolerant combination (heat-tolerant × heat-tolerant possessed heat tolerance, whereas the susceptible combinations were crossed by heat-tolerant (sterile lines × heat-susceptible (restorer lines, heat-susceptible × heat-tolerant, or heat-susceptible × heat-susceptible parents. This result indicated that heat tolerance in rice was controlled by recessive genes. Thus, both parents should possess high temperature tolerance to develop heat-tolerant F1 combinations. Furthermore, the heat stress index of F1 combinations was significantly correlated with the heat stress index of restorer lines but not with the heat stress index of maintainer lines. This result suggested that male parents play a more important role in heat-tolerant combinations than female parents. Therefore, the heat susceptibility of the hybrid rice in China is mainly due to the wide application of low-heat-tolerant restorer lines with high yield in three-line hybrid rice breeding.

  12. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto

    In prospects of global climate change, heat stress is a rising constraint for the productivity of wheat (Triticum aestivum L.). It is a heat-susceptible crop beyond 17-23oC temperature throughout its phenological stages, flowering phase being the most sensitive stage. Chlorophyll a fluorescence...... parameter, maximum quantum yield efficiency of PSII (Fv/Fm) is used as a physiological marker for early stress detection in PSII in plants. We established a reproducible protocol to measure response of wheat genotypes to high temperature based on Fv/Fm. The heat treatment of 40°C in 300 µmol m-2s-1 PAR...... enabled the identification of contrasting wheat genotypes that can be used to study the genetic and physiological nature of heat stress tolerance to dissect quantitative traits into simpler and more heritable traits....

  13. Promoting Communication: Teaching Tolerance of Homosexual Persons While Addressing Religious Fears.

    Science.gov (United States)

    Levesque, PJ

    This paper addresses how to teach tolerance of homosexual persons in a manner that is not threatening to those with religious scruples about homosexuals. It contains an example of a presentation for college students that is designed to teach them to respect their peers and future coworkers regardless of their sexual orientation. The presentation…

  14. CORRELATION AND HEAT SUSCEPTIBILITY INDEX ANALYSIS FOR TERMINAL HEAT TOLERANCE IN BREAD WHEAT

    Directory of Open Access Journals (Sweden)

    Ankit SHARMA

    2013-06-01

    Full Text Available Six generations namely, P1, P2, F2, F3, BC1s and BC2s (2006-07 and P1, P2, F3, F4, BC1ss and BC2ss (2007-08 developed from four parental genotypes viz. DBW 14 (heat tolerant, NP 846 (heat and drought tolerant, WH 147 and Raj 4014 (heat susceptible for late sown. All the six generations from four crosses were evaluated during Rabi 2006-07 and Rabi 2007-08 in a compact family block design with three replications on two sowing dates. Heat susceptibility index values revealed reduction in grain yield in both the years for all the generations of the four crosses. Significant estimates of correlation of grain yield with days to heading, days to anthesis and days to maturity were recorded in late sown condition during first year. While under timely sown condition spike length has high estimate correlation with grain yield in first year itself. Significant estimated were recorded for tillers per plant in both the environments in second year. Lowest yield loss was reported in backcross populations of Cross I in both years and among segregating populations of Cross IV observed to be least affected and therefore suggested to be forwarded to further generations and further selection of heat tolerant genotypes.

  15. Heated Allergens and Induction of Tolerance in Food Allergic Children

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    Irmeli Penttila

    2013-06-01

    Full Text Available Food allergies are one of the first manifestations of allergic disease and have been shown to significantly impact on general health perception, parental emotional distress and family activities. It is estimated that in the Western world, almost one in ten children have an IgE-mediated allergy. Cow’s milk and egg allergy are common childhood allergies. Until recently, children with food allergy were advised to avoid all dietary exposure to the allergen to which they were sensitive, in the thought that consumption would exacerbate their allergy. However, recent publications indicate that up to 70% of children with egg allergy can tolerate egg baked in a cake or muffin without apparent reaction. Likewise, up to 75% of children can tolerate baked goods containing cow’s milk, and these children demonstrate IgE and IgG4 profiles indicative of tolerance development. This article will review the current literature regarding the use of heated food allergens as immunotherapy for children with cow’s milk and egg allergy.

  16. Identification for Heat Tolerance in Backcross Recombinant Lines and Screening of Backcross Introgression Lines with Heat Tolerance at Milky Stage in Rice

    Directory of Open Access Journals (Sweden)

    Jiang-lin LIAO

    2011-12-01

    Full Text Available The present study aimed at breeding new rice germplasms with similar genome but significantly differed in heat tolerance during the grain filling stage. A total of 791 BC1F8 backcross recombinant lines, derived from the cross of Xieqingzao B / N22 // Xieqingzao B, were used as materials. Each rice line was separated evenly into two groups, and the heat tolerance of all rice lines were evaluated at natural high temperature in fields. The rice lines with heat tolerant index higher than 90% or lower than 40% were selected to compare the phenotypic characters and further identify heat tolerance at the early milky stage in a phytotron. Rice lines with similar phenotypic characters but significantly differed in heat tolerance at the milky stage were analyzed by 887 simple sequence repeat markers that were evenly distributed on the 12 rice chromosomes. In the result, 12 (6 pairs rice lines with similar phenotypic characters but significantly differed in heat tolerance at the milky stage were obtained. Molecular marker analysis indicated that the genomic polymorphism between 703T and 704S was the smallest in the 6 pairs of rice lines, with only 16 polymorphic sites, including 22 different alleles. The application of these two backcross introgression rice lines for future study on the mechanisms of heat tolerance in rice at the milky stage will be theoretically beneficial in reducing the interference caused by genetic differences from experimental materials.

  17. Tolerence for work-induced heat stress in men wearing liquidcooled garments

    Science.gov (United States)

    Blockley, W. V.; Roth, H. P.

    1971-01-01

    An investigation of the heat tolerance in men unable to dispose of metabolic heat as fast as it is produced within the body is discussed. Examinations were made of (a) the effect of work rate (metabolic rate) on tolerance time when body heat storage rate is a fixed quantity, and (b) tolerance time as a function of metabolic rate when heat loss is terminated after a thermal quasi-equilibrium was attained under comfortable conditions of heat transfer. The nature of the physiological mechanisms involved in such heat stress situations, and the possibility of using prediction techniques to establish standard procedures in emergencies involving cooling system failures are also discussed.

  18. Addresses

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — Point features representing locations of all street addresses in Orange County, NC including Chapel Hill, NC. Data maintained by Orange County, the Town of Chapel...

  19. Temperature stress differentially modulates transcription in meiotic anthers of heat-tolerant and heat-sensitive tomato plants

    Directory of Open Access Journals (Sweden)

    Pezzotti Mario

    2011-07-01

    Full Text Available Abstract Background Fluctuations in temperature occur naturally during plant growth and reproduction. However, in the hot summers this variation may become stressful and damaging for the molecular mechanisms involved in proper cell growth, impairing thus plant development and particularly fruit-set in many crop plants. Tolerance to such a stress can be achieved by constitutive gene expression or by rapid changes in gene expression, which ultimately leads to protection against thermal damage. We have used cDNA-AFLP and microarray analyses to compare the early response of the tomato meiotic anther transcriptome to moderate heat stress conditions (32°C in a heat-tolerant and a heat-sensitive tomato genotype. In the light of the expected global temperature increases, elucidating such protective mechanisms and identifying candidate tolerance genes can be used to improve breeding strategies for crop tolerance to heat stress. Results The cDNA-AFLP analysis shows that 30 h of moderate heat stress (MHS alter the expression of approximately 1% of the studied transcript-derived fragments in a heat-sensitive genotype. The major effect is gene down-regulation after the first 2 h of stress. The microarray analysis subsequently applied to elucidate early responses of a heat-tolerant and a heat-sensitive tomato genotype, also shows about 1% of the genes having significant changes in expression after the 2 h of stress. The tolerant genotype not only reacts with moderate transcriptomic changes but also exhibits constitutively higher expression levels of genes involved in protection and thermotolerance. Conclusion In contrast to the heat-sensitive genotype, the heat-tolerant genotype exhibits moderate transcriptional changes under moderate heat stress. Moreover, the heat-tolerant genotype also shows a different constitutive gene expression profile compared to the heat-sensitive genotype, indicating genetic differences in adaptation to increased temperatures. In

  20. Comparison of investigation methods of heat injury in grapevine (Vitis) and assessment to heat tolerance in different cultivars and species.

    Science.gov (United States)

    Xu, Hongguo; Liu, Guojie; Liu, Guotian; Yan, Bofang; Duan, Wei; Wang, Lijun; Li, Shaohua

    2014-06-05

    In the context of global climate change, heat stress is becoming an increasingly important constraint on grapevine growth and berry quality. There is a need to breed new grape cultivars with heat tolerance and to design effective physiological defenses against heat stress. The investigation of heat injury to plants or tissues under high temperature is an important step in achieving these goals. At present, evaluation methods for heat injury include the gas exchange parameters of photosynthesis, membrane thermostability, chlorophyll content etc.; however, these methods have obvious disadvantages, such as insensitivity, inconvenience and delayed information. An effective and convenient method for investigating the heat injury of grapevine must be developed. In this study, an investigation protocol for a critical temperature (47°C) and heat treatment time (40 min) was developed in detached grape leaves. Based on the results, we found that the OJIP test was superior to measuring electrolyte leakage or photosynthetic O₂ evolution for investigating the heat injury of three cultivars of grapevine. Heat tolerance of 47 grape species and cultivars was evaluated through investigating heat injury using the OJIP test. Moreover, the electron transport chain (donor side, acceptor side and reaction center) of PSII in photosynthesis was further investigated. The OJIP test was a rapid, sensitive and convenient method for investigating heat injury in grapevine. An analysis of PSII function using this method indicated that the acceptor side was less sensitive to heat than was the donor side or the reaction center in grape leaves. Among the 47 taxa evaluated (cultivars, hybrids, and wild species), heat tolerance varied largely in each genotype group: most wild species and hybrids between V. labrusca and V. vinifera had relatively strong heat tolerance, but most cultivars from V. vinifera had relatively weak heat tolerance.

  1. Avian thermoregulation in the heat: resting metabolism, evaporative cooling and heat tolerance in Sonoran Desert songbirds.

    Science.gov (United States)

    Smith, Eric Krabbe; O'Neill, Jacqueline J; Gerson, Alexander R; McKechnie, Andrew E; Wolf, Blair O

    2017-09-15

    We examined thermoregulatory performance in seven Sonoran Desert passerine bird species varying in body mass from 10 to 70 g - lesser goldfinch, house finch, pyrrhuloxia, cactus wren, northern cardinal, Abert's towhee and curve-billed thrasher. Using flow-through respirometry, we measured daytime resting metabolism, evaporative water loss and body temperature at air temperatures ( T air ) between 30 and 52°C. We found marked increases in resting metabolism above the upper critical temperature ( T uc ), which for six of the seven species fell within a relatively narrow range (36.2-39.7°C), but which was considerably higher in the largest species, the curve-billed thrasher (42.6°C). Resting metabolism and evaporative water loss were minimal below the T uc and increased with T air and body mass to maximum values among species of 0.38-1.62 W and 0.87-4.02 g H 2 O h -1 , respectively. Body temperature reached maximum values ranging from 43.5 to 45.3°C. Evaporative cooling capacity, the ratio of evaporative heat loss to metabolic heat production, reached maximum values ranging from 1.39 to 2.06, consistent with known values for passeriforms and much lower than values in taxa such as columbiforms and caprimulgiforms. These maximum values occurred at heat tolerance limits that did not scale with body mass among species, but were ∼50°C for all species except the pyrrhuloxia and Abert's towhee (48°C). High metabolic costs associated with respiratory evaporation appeared to drive the limited heat tolerance in these desert passeriforms, compared with larger desert columbiforms and galliforms that use metabolically more efficient mechanisms of evaporative heat loss. © 2017. Published by The Company of Biologists Ltd.

  2. Use of Heat Stress Responsive Gene Expression Levels for Early Selection of Heat Tolerant Cabbage (Brassica oleracea L.

    Directory of Open Access Journals (Sweden)

    Jun Cheul Ahn

    2013-06-01

    Full Text Available Cabbage is a relatively robust vegetable at low temperatures. However, at high temperatures, cabbage has disadvantages, such as reduced disease tolerance and lower yields. Thus, selection of heat-tolerant cabbage is an important goal in cabbage breeding. Easier or faster selection of superior varieties of cabbage, which are tolerant to heat and disease and have improved taste and quality, can be achieved with molecular and biological methods. We compared heat-responsive gene expression between a heat-tolerant cabbage line (HTCL, “HO”, and a heat-sensitive cabbage line (HSCL, “JK”, by Genechip assay. Expression levels of specific heat stress-related genes were increased in response to high-temperature stress, according to Genechip assays. We performed quantitative RT-PCR (qRT-PCR to compare expression levels of these heat stress-related genes in four HTCLs and four HSCLs. Transcript levels for heat shock protein BoHsp70 and transcription factor BoGRAS (SCL13 were more strongly expressed only in all HTCLs compared to all HSCLs, showing much lower level expressions at the young plant stage under heat stress (HS. Thus, we suggest that expression levels of these genes may be early selection markers for HTCLs in cabbage breeding. In addition, several genes that are involved in the secondary metabolite pathway were differentially regulated in HTCL and HSCL exposed to heat stress.

  3. heat-induced biological changes as heat tolerance indices related to growth performance in buffaloes

    International Nuclear Information System (INIS)

    Kaldes, M.Z.N.

    2004-01-01

    the main objective of this study was to predict new heat tolerance indices related to hot summer growth performance, depending on heat - induced changes in some physiological and biochemical parameters of young water buffalo calves. the present study was carried out on 8 egyptian male buffalo calves of 6 months old and 106.8 kg mean body weight (B W), and on the same animals of 12 months old and 179.5 kg mean B W. the animals were maintained in a climatic chamber of the egyptian atomic energy authority. the animals were maintained in metabolic cages inside a climatic chamber for 3 weeks under mild climate (20-24 c and 50-60% Rh, equivalent to 62-72 THI) for 6 hours daily as adjustment period,followed by 5 and 7 days in the 6- and 12-month old calves, respectively at the same climatic conditions as a control period.this was followed by 6 hours of acute heat exposure period (33-43 c and 40-60% Rh, equivalent to 85-93 Thi), then by chronic heat exposure period of the same climatic conditions for 5 and 7 days in the 6- and 12- month old calves, respectively.Rectal temperature (RT) and respiration rate (RR) were estimated daily, whereas BW was estimated at the beginning and the end of each exposure period

  4. Simple Screening Methods for Drought and Heat Tolerance in Cowpea

    International Nuclear Information System (INIS)

    Singh, B. B.

    2000-10-01

    Success in breeding for drought tolerance has not been as pronounced as for other traits. This is partly due to lack of simple, cheap and reliable screening methods to select drought tolerant plants/progenies from the segregating populations and partly due to complexity of factors involved in drought tolerance. Measuring drought tolerance through physiological parameters is expensive, time consuming and difficult to use for screening large numbers of lines and segregating populations. Since several factors/mechanisms (in shoot and root) operate independently and/or jointly to enable plants to cope with drought stress, drought tolerance appears as a complex trait. However, if these factors/mechanisms can be separated and studied individually, the components leading to drought tolerance will appear less complex and may be easy to manipulate by breeders. We have developed a simple box screening method for shoot drought tolerance in cowpea, which eliminates the effects of roots and permits non-destructive visual identification of shoot dehydration tolerance. We have also developed a 'root-box pin-board' method to study two dimensional root architecture of individual plants. Using these methods, we have identified two mechanisms of shoot drought tolerance in cowpea which are controlled by single dominant genes and major difference for root architecture among cowpea varieties. Combining deep and dense root system with shoot dehydration tolerance results into highly drought tolerant plants

  5. Bacterial community dynamics are linked to patterns of coral heat tolerance

    KAUST Repository

    Ziegler, Maren

    2017-02-10

    Ocean warming threatens corals and the coral reef ecosystem. Nevertheless, corals can be adapted to their thermal environment and inherit heat tolerance across generations. In addition, the diverse microbes that associate with corals have the capacity for more rapid change, potentially aiding the adaptation of long-lived corals. Here, we show that the microbiome of reef corals is different across thermally variable habitats and changes over time when corals are reciprocally transplanted. Exposing these corals to thermal bleaching conditions changes the microbiome for heat-sensitive corals, but not for heat-tolerant corals growing in habitats with natural high heat extremes. Importantly, particular bacterial taxa predict the coral host response in a short-term heat stress experiment. Such associations could result from parallel responses of the coral and the microbial community to living at high natural temperatures. A competing hypothesis is that the microbial community and coral heat tolerance are causally linked.

  6. High Resolution Mapping of QTLs for Heat Tolerance in Rice Using a 5K SNP Array.

    Science.gov (United States)

    Ps, Shanmugavadivel; Sv, Amitha Mithra; Prakash, Chandra; Mk, Ramkumar; Tiwari, Ratan; Mohapatra, Trilochan; Singh, Nagendra Kumar

    2017-12-01

    Heat stress is one of the major abiotic threats to rice production, next to drought and salinity stress. Incidence of heat stress at reproductive phase of the crop results in abnormal pollination leading to floret sterility, low seed set and poor grain quality. Identification of QTLs and causal genes for heat stress tolerance at flowering will facilitate breeding for improved heat tolerance in rice. In the present study, we used 272 F 8 recombinant inbred lines derived from a cross between Nagina22, a well-known heat tolerant Aus cultivar and IR64, a heat sensitive popular Indica rice variety to map the QTLs for heat tolerance. To enable precise phenotyping for heat stress tolerance, we used a controlled phenotyping facility available at ICAR-Indian Institute of Wheat and Barley Research, Karnal, India. Based on 'days to 50% flowering' data of the RILs, we followed staggered sowing to synchronize flowering to impose heat stress at uniform stage. Using the Illumina infinium 5K SNP array for genotyping the parents and the RILs, and stress susceptibility and stress tolerance indices (SSI and STI) of percent spikelet sterility and yield per plant (g), we identified five QTLs on chromosomes 3, 5, 9 and 12. The identified QTLs explained phenotypic variation in the range of 6.27 to 21. 29%. Of these five QTLs, two high effect QTLs, one novel (qSTIPSS9.1) and one known (qSTIY5.1/qSSIY5.2), were mapped in less than 400 Kbp genomic regions, comprising of 65 and 54 genes, respectively. The present study identified two major QTLs for heat tolerance in rice in narrow physical intervals, which can be employed for crop improvement by marker assisted selection (MAS) after development of suitable scorable markers for breeding of high yielding heat tolerant rice varieties. This is the first report of a major QTL for heat tolerance on chromosome 9 of rice. Further, a known QTL for heat tolerance on chromosome 5 was narrowed down from 23 Mb to 331 Kbp in this study.

  7. Thermal tolerances of fish from a reservoir receiving heated effluent from a nuclear reactor

    International Nuclear Information System (INIS)

    Holland, W.E.; Smith, M.H.; Gibbons, J.W.; Brown, D.H.

    1974-01-01

    The heat tolerances of bluegill (Lepomis macrochirus) subjected to heated effluent from a nuclear reactor was compared with those of bluegill living at normal temperatures. Three of the four study areas were located in the Par Pond reservoir system on the Savannah River Plant near Aiken, South Carolina. Results shown that at least one species of warm-water fish can adjust to elevated aquatic temperatures in a natural environment by becoming more tolerant. (U.S.)

  8. Assessment of stress tolerance acquisition in the heat-tolerant derivative strains of Bifidobacterium animalis subsp. lactis BB-12 and Lactobacillus rhamnosus GG.

    Science.gov (United States)

    Aakko, J; Sánchez, B; Gueimonde, M; Salminen, S

    2014-07-01

    The purpose of this study was to investigate the heat-shock response at molecular level in Lactobacillus rhamnosus GG, Bifidobacterium animalis subsp. lactis BB-12 and their heat-tolerant derivatives and to characterize the changes that make the derivatives more robust in terms of heat stress. The study strains were exposed for 2 h to a heat-shock treatment, Bif. animalis subsp. lactis BB-12 and its derivative at 50°C and the Lact. rhamnosus GG and its derivative at 60°C. Protein synthesis before and after heat shock was examined using proteomics and RT-qPCR. The analysis revealed that the regulation of seven proteins in both strain pairs was modified as a response to heat or between the original and the derivative strain. The comparison of wild-type strains and the heat-tolerant derivatives suggests that the acquisition of heat tolerance in the Bif. animalis subsp. lactis BB-12 derivative is due to a slightly increased constitutive level of chaperones, while in Lact. rhamnosus GG derivative, the main reason seems to be a higher ability to induce the production of chaperones. This study revealed possible markers of heat tolerance in B. lactis and Lact. rhamnosus strains. This study increases our knowledge on how Lactobacillus and Bifidobacterium strains may acquire heat tolerance. These findings may be useful for improving the heat tolerance of existing probiotic strains as well as screening new heat-tolerant strains. © 2014 The Society for Applied Microbiology.

  9. A three-tier phenotyping approach for hunting QTLs related to heat tolerance in bread wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Rosenqvist, Eva; Ottosen, Carl-Otto

    In the global climate change scenario, heatstress together with other abiotic stresses will remain an importantdeterminant of future food security. Wheat (Triticum aestivum L.) is the third most important crop, feeding about one third of the world population. Being a crop of temperate climate......, wheat is sensitive to heat stress, particularly at the reproductive phase. Heat tolerance is a complex trait. In the present study, a combined approach of physiological phenotyping and quantitative genetics was used to dissect the complex nature of heat tolerance into photosynthesis related traits......- with a top-to-bottom (forward) approach: Tier 1: Phenotyping: As a starting point,the quantification of heat tolerance was done by the chlorophyll fluorescence parameter, Fv/Fm, as a measure of maximum quantum efficiency of PSII photochemistry after heat stress treatment (40°C for 72h). This way...

  10. A three-tier phenotyping approach for hunting QTLs related to heat tolerance in bread wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Rosenqvist, Eva; Ottosen, Carl-Otto

    2014-01-01

    In the global climate change scenario, heatstress together with other abiotic stresses will remain an importantdeterminant of future food security. Wheat (Triticum aestivum L.) is the third most important crop, feeding about one third of the world population. Being a crop of temperate climate......, wheat is sensitive to heat stress, particularly at the reproductive phase. Heat tolerance is a complex trait. In the present study, a combined approach of physiological phenotyping and quantitative genetics was used to dissect the complex nature of heat tolerance into photosynthesis related traits......- with a top-to-bottom (forward) approach: Tier 1: Phenotyping: As a starting point,the quantification of heat tolerance was done by the chlorophyll fluorescence parameter, Fv/Fm, as a measure of maximum quantum efficiency of PSII photochemistry after heat stress treatment (40°C for 72h). This way...

  11. Candidate genes and molecular markers associated with heat tolerance in colonial Bentgrass.

    Directory of Open Access Journals (Sweden)

    David Jespersen

    Full Text Available Elevated temperature is a major abiotic stress limiting the growth of cool-season grasses during the summer months. The objectives of this study were to determine the genetic variation in the expression patterns of selected genes involved in several major metabolic pathways regulating heat tolerance for two genotypes contrasting in heat tolerance to confirm their status as potential candidate genes, and to identify PCR-based markers associated with candidate genes related to heat tolerance in a colonial (Agrostis capillaris L. x creeping bentgrass (Agrostis stolonifera L. hybrid backcross population. Plants were subjected to heat stress in controlled-environmental growth chambers for phenotypic evaluation and determination of genetic variation in candidate gene expression. Molecular markers were developed for genes involved in protein degradation (cysteine protease, antioxidant defense (catalase and glutathione-S-transferase, energy metabolism (glyceraldehyde-3-phosphate dehydrogenase, cell expansion (expansin, and stress protection (heat shock proteins HSP26, HSP70, and HSP101. Kruskal-Wallis analysis, a commonly used non-parametric test used to compare population individuals with or without the gene marker, found the physiological traits of chlorophyll content, electrolyte leakage, normalized difference vegetative index, and turf quality were associated with all candidate gene markers with the exception of HSP101. Differential gene expression was frequently found for the tested candidate genes. The development of candidate gene markers for important heat tolerance genes may allow for the development of new cultivars with increased abiotic stress tolerance using marker-assisted selection.

  12. Heat Priming Induces Trans-generational Tolerance to High Temperature Stress in Wheat

    OpenAIRE

    Wang, Xiao; Xin, Caiyun; Cai, Jian; Zhou, Qin; Dai, Tingbo; Cao, Weixing; Jiang, Dong

    2016-01-01

    Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH), the progeny of heat-primed plants (PH) possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the tran...

  13. Adult Heat Tolerance Variation in Drosophila melanogaster is Not Related to Hsp70 Expression

    DEFF Research Database (Denmark)

    Jensen, Louise Toft; Cockerell, Fiona Elizabeth; Kristensen, Torsten Nygaard

    2010-01-01

    in Drosophila larvae Hsp70 expression may be a key determinant of heat tolerance, the evidence for this in adults is equivocal. We therefore examined heat-induced Hsp70 expression and several measurements of adult heat tolerance in three independent collections of D. melanogaster, measured in three laboratories...

  14. Comprehensive assessment of geographic variation in heat tolerance and hardening capacity in populations of Drosophila melanogaster from eastern Australia

    DEFF Research Database (Denmark)

    Sgro, Carla M.; Overgaard, Johannes; Kristensen, Torsten Nygård

    2010-01-01

    We examined latitudinal variation in adult and larval heat tolerance in Drosophila melanogaster from eastern Australia. Adults were assessed using static and ramping assays. Basal and hardened static heat knockdown time showed significant linear clines; heat tolerance increased towards the tropics...

  15. Intrinsic tolerance of Bifidobacterium species to heat and oxygen and survival following spray drying and storage.

    Science.gov (United States)

    Simpson, P J; Stanton, C; Fitzgerald, G F; Ross, R P

    2005-01-01

    This study examined the tolerance of various species of the genus Bifidobacterium to heat and oxygen and evaluated the survival of selected strains following spray drying and during storage. Nine Bifidobacterium species were considered to be relatively tolerant to both heat and oxygen and mostly segregated into two clusters within the 16S rDNA phylogenetic tree. Four species were tolerant to oxygen and 12 species were considered sensitive to oxygen and heat. Using a skimmed milk-based carrier good survival following spray drying and storage at 4 degrees C correlated with tolerance to heat and oxygen. Viability was inversely related to storage temperature and at 15 degrees C and 25 degrees C, a significant decline was observed for all species. The inclusion of gum acacia had no significant affect on survival or viability. However, using a fluidized-bed spray dryer viability was greatly improved. A group of closely related species tolerant to heat and oxygen had high survival following spray drying and maintained viability during prolonged storage at 4 degrees C. Spray drying is a suitable method for the production of skimmed milk powder enriched with high numbers of viable bifidobacteria.

  16. In vitro induction of variability through radiation for late blight resistance and heat tolerance in potato

    International Nuclear Information System (INIS)

    Gosal, S.S.; Das, A.; Gopal, J.; Minocha, J.L.; Chopra, H.R.; Dhaliwal, H.S.

    2001-01-01

    In vitro cultured shoots of potato, cvs. 'Kufri Jyoti' and 'Kufri Chandramukhi', were irradiated with 20 and 40 Gy gamma rays. Microtubers, obtained from MIV3 shoots multiplied in vitro, were planted in pots. The resulting plants were screened for resistance to late blight, using detached leaf method. In 'Kufri Chandramukhi', 42% plants and in 'Kufri Jyoti' 36% plants, obtained from 40 Gy treatment, showed resistance to late blight. The frequency of resistant plants was lower from 20 Gy treatment. The progenies of putatively resistant plants were grown in field, and inoculated with sporangial inoculum of late blight fungus. The field grown progeny segregated for disease resistance, and approximately 56% plants showed resistance. During the next propagation, the frequency of resistant plants increased to 72%. For developing heat tolerance, microtubers obtained from 20 and 40 Gy treatments and in vitro multiplied M 1 V 3 shoots were cultured at high temperature of 28C. In both varieties, the number of the microtubers per plant was highly reduced and the resulting microtubers had distorted shape but showed better germination (62%), even in early sowing at relatively higher temperature. Of the two radiation doses, the higher dose of 40 Gy gave better results in both the varieties. Heat tolerance was also assessed from chlorophyll persistence. The progenies from putative heat-tolerant plants were tested in field by planting at higher temperature in two subsequent generations. The heat tolerant plants segregated in each generation, but the frequency of heat-tolerant plants increased. (author)

  17. Acid, bile, and heat tolerance of free and microencapsulated probiotic bacteria.

    Science.gov (United States)

    Ding, W K; Shah, N P

    2007-11-01

    Eight strains of probiotic bacteria, including Lactobacillus rhamnosus, Bifidobacterium longum, L. salivarius, L. plantarum, L. acidophilus, L. paracasei, B. lactis type Bl-O4, and B. lactis type Bi-07, were studied for their acid, bile, and heat tolerance. Microencapsulation in alginate matrix was used to enhance survival of the bacteria in acid and bile as well as a brief exposure to heat. Free probiotic organisms were used as a control. The acid tolerance of probiotic organisms was tested using HCl in MRS broth over a 2-h incubation period. Bile tolerance was tested using 2 types of bile salts, oxgall and taurocholic acid, over an 8-h incubation period. Heat tolerance was tested by exposing the probiotic organisms to 65 degrees C for up to 1 h. Results indicated microencapsulated probiotic bacteria survived better (P strains. At 30 min of heat treatment, microencapsulated probiotic bacteria survived with an average loss of only 4.17-log CFU/mL, compared to 6.74-log CFU/mL loss with free probiotic bacteria. However, after 1 h of heating both free and microencapsulated probiotic strains showed similar losses in viability. Overall microencapsulation improved the survival of probiotic bacteria when exposed to acidic conditions, bile salts, and mild heat treatment.

  18. Nitric Oxide (NO) in Plant Heat Stress Tolerance: Current Knowledge and Perspectives.

    Science.gov (United States)

    Parankusam, Santisree; Adimulam, Srivani S; Bhatnagar-Mathur, Pooja; Sharma, Kiran K

    2017-01-01

    High temperature is one of the biggest abiotic stress challenges for agriculture. While, Nitric oxide (NO) is gaining increasing attention from plant science community due to its involvement in resistance to various plant stress conditions, its implications on heat stress tolerance is still unclear. Several lines of evidence indicate NO as a key signaling molecule in mediating various plant responses such as photosynthesis, oxidative defense, osmolyte accumulation, gene expression, and protein modifications under heat stress. Furthermore, the interactions of NO with other signaling molecules and phytohormones to attain heat tolerance have also been building up in recent years. Nevertheless, deep insights into the functional intermediaries or signal transduction components associated with NO-mediated heat stress signaling are imperative to uncover their involvement in plant hormone induced feed-back regulations, ROS/NO balance, and stress induced gene transcription. Although, progress is underway, much work remains to define the functional relevance of this molecule in plant heat tolerance. This review provides an overview on current status and discuss knowledge gaps in exploiting NO, thereby enhancing our understanding of the role of NO in plant heat tolerance.

  19. Characterization of heat tolerance in wheat cultivars and effects on production components

    Directory of Open Access Journals (Sweden)

    Adérico Júnior Badaró Pimentel

    2015-04-01

    Full Text Available Abstract: There is a need for heat tolerant wheat cultivars adapted to the expansion of cultivation areas in warmer regions due to the high demand of this cereal for human consumption. The objective of this study was to evaluate the effect of high temperatures on grain yield and yield components of wheat and characterize heat tolerant wheat genotypes at different development stages. The genotypes were evaluated in the field with and without heat stress. High temperatures reduced the number of spikelets per spike (21%, number of grains per spike (39%, number of grains per spikelet (23%, 1000-grain weight (27% and grain yield (79%. Cultivars MGS 1 Aliança, Embrapa 42, IAC 24-Tucuruí and IAC 364-Tucuruí III are the most tolerant to heat stress between the stages double ridge and terminal spikelet; MGS 1 Aliança, BRS 264, IAC 24-Tucuruí, IAC 364-Tucuruí III and VI 98053, between meiosis and anthesis; and BRS 254, IAC-24-Tucuruí, IAC-364-Tucuruí III and VI 98053, between anthesis and physiological maturity. High temperatures reduce grain yield and yield components. The number of grains per spike is the most reduced component under heat stress. The genotypes differed in tolerance to heat stress in different developmental stages.

  20. Metabolic Pathways Involved in Carbon Dioxide Enhanced Heat Tolerance in Bermudagrass

    Directory of Open Access Journals (Sweden)

    Jingjin Yu

    2017-09-01

    Full Text Available Global climate changes involve elevated temperature and CO2 concentration, imposing significant impact on plant growth of various plant species. Elevated temperature exacerbates heat damages, but elevated CO2 has positive effects on promoting plant growth and heat tolerance. The objective of this study was to identify metabolic pathways affected by elevated CO2 conferring the improvement of heat tolerance in a C4 perennial grass species, bermudagrass (Cynodon dactylon Pers.. Plants were planted under either ambient CO2 concentration (400 μmol⋅mol-1 or elevated CO2 concentration (800 μmol⋅mol-1 and subjected to ambient temperature (30/25°C, day/night or heat stress (45/40°C, day/night. Elevated CO2 concentration suppressed heat-induced damages and improved heat tolerance in bermudagrass. The enhanced heat tolerance under elevated CO2 was attributed to some important metabolic pathways during which proteins and metabolites were up-regulated, including light reaction (ATP synthase subunit and photosystem I reaction center subunit and carbon fixation [(glyceraldehyde-3-phosphate dehydrogenase, GAPDH, fructose-bisphosphate aldolase, phosphoglycerate kinase, sedoheptulose-1,7-bisphosphatase and sugars of photosynthesis, glycolysis (GAPDH, glucose, fructose, and galactose and TCA cycle (pyruvic acid, malic acid and malate dehydrogenase of respiration, amino acid metabolism (aspartic acid, methionine, threonine, isoleucine, lysine, valine, alanine, and isoleucine as well as the GABA shunt (GABA, glutamic acid, alanine, proline and 5-oxoproline. The up-regulation of those metabolic processes by elevated CO2 could at least partially contribute to the improvement of heat tolerance in perennial grass species.

  1. QTL-seq analysis of heat tolerance in broccoli

    Science.gov (United States)

    Broccoli (Brassica oleracea var. italica) production, worth approximately a billion dollars annually in the United States alone, is restricted in terms of location and season, due to the sensitivity of commercial cultivars to high temperatures. Heat stress during heading causes yield and quality los...

  2. Exercise increases pressure pain tolerance but not pressure and heat pain thresholds in healthy young men

    DEFF Research Database (Denmark)

    Vaegter, H B; Hoeger Bement, M; Madsen, A B

    2017-01-01

    : On three different days, 20 healthy young men performed two submaximal isometric knee extensions (30% maximal voluntary contraction in 3 min) and a control condition (quiet rest). Before and immediately after exercise and rest, the sensitivity to heat pain and pressure pain was assessed in randomized...... and counterbalanced order. Cuff pressure pain threshold (cPPT) and pain tolerance (cPTT) were assessed on the ipsilateral lower leg by computer-controlled cuff algometry. Heat pain threshold (HPT) was recorded on the ipsilateral foot by a computer-controlled thermal stimulator. RESULTS: Cuff pressure pain tolerance...

  3. Infrared Thermography to Evaluate Heat Tolerance in Different Genetic Groups of Lambs.

    Science.gov (United States)

    McManus, Concepta; Bianchini, Eliandra; Paim, Tiago do Prado; de Lima, Flavia Gontijo; Neto, José Braccini; Castanheira, Marlos; Esteves, Geisa Isilda Ferreira; Cardoso, Caio Cesar; Dalcin, Vanessa Calderaro

    2015-07-16

    Heat stress is considered a limiting factor for sheep production. We used information from physiological characteristics linked to heat tolerance to determine whether infrared thermography temperatures were able to separate groups of animals and determine the most important variables in this differentiation. Forty-eight four-month-old male lambs from eight genetic groups were used. Physiological (rectal temperature-RT, heart rate-HR, respiratory rate-RR) and blood traits, infrared thermography temperatures, heat tolerance indices, body measurements, weight and carcass traits were measured. Statistical analyses included variance, correlations, factor, discrimination and regression. Observing the correlations between physiological characteristics (RT, RR and HR) with temperatures measured by infrared thermography, regions for further studies should include the mean temperature of flank, nose and rump. Results show that there are strong relationships between thermograph measurements and RR, RT and HR in lambs, which are suggested to be directly correlated with heat tolerance capacity of the different genetic groups evaluated in this study. The assessment of body surface temperature measured by the thermograph could be used as a noninvasive tool to assess heat tolerance of the animals.

  4. Insights into the Molecular Events That Regulate Heat-Induced Chilling Tolerance in Citrus Fruits

    Directory of Open Access Journals (Sweden)

    María T. Lafuente

    2017-06-01

    Full Text Available Low non-freezing temperature may cause chilling injury (CI, which is responsible for external quality deterioration in many chilling-sensitive horticultural crops. Exposure of chilling-sensitive citrus cultivars to non-lethal high-temperature conditioning may increase their chilling tolerance. Very little information is available about the molecular events involved in such tolerance. In this work, the molecular events associated with the low temperature tolerance induced by heating Fortune mandarin, which is very sensitive to chilling, for 3 days at 37°C prior to cold storage is presented. A transcriptomic analysis reveals that heat-conditioning has an important impact favoring the repression of genes in cold-stored fruit, and that long-term heat-induced chilling tolerance is an active process that requires activation of transcription factors involved in transcription initiation and of the WRKY family. The analysis also shows that chilling favors degradation processes, which affect lipids and proteins, and that the protective effect of the heat-conditioning treatment is more likely to be related to the repression of the genes involved in lipid degradation than to the modification of fatty acids unsaturation, which affects membrane permeability. Another major factor associated with the beneficial effect of the heat treatment on reducing CI is the regulation of stress-related proteins. Many of the genes that encoded such proteins are involved in secondary metabolism and in oxidative stress-related processes.

  5. Insights into the Molecular Events That Regulate Heat-Induced Chilling Tolerance in Citrus Fruits.

    Science.gov (United States)

    Lafuente, María T; Establés-Ortíz, Beatriz; González-Candelas, Luis

    2017-01-01

    Low non-freezing temperature may cause chilling injury (CI), which is responsible for external quality deterioration in many chilling-sensitive horticultural crops. Exposure of chilling-sensitive citrus cultivars to non-lethal high-temperature conditioning may increase their chilling tolerance. Very little information is available about the molecular events involved in such tolerance. In this work, the molecular events associated with the low temperature tolerance induced by heating Fortune mandarin, which is very sensitive to chilling, for 3 days at 37°C prior to cold storage is presented. A transcriptomic analysis reveals that heat-conditioning has an important impact favoring the repression of genes in cold-stored fruit, and that long-term heat-induced chilling tolerance is an active process that requires activation of transcription factors involved in transcription initiation and of the WRKY family. The analysis also shows that chilling favors degradation processes, which affect lipids and proteins, and that the protective effect of the heat-conditioning treatment is more likely to be related to the repression of the genes involved in lipid degradation than to the modification of fatty acids unsaturation, which affects membrane permeability. Another major factor associated with the beneficial effect of the heat treatment on reducing CI is the regulation of stress-related proteins. Many of the genes that encoded such proteins are involved in secondary metabolism and in oxidative stress-related processes.

  6. Infrared Thermography to Evaluate Heat Tolerance in Different Genetic Groups of Lambs

    Directory of Open Access Journals (Sweden)

    Concepta McManus

    2015-07-01

    Full Text Available Heat stress is considered a limiting factor for sheep production. We used information from physiological characteristics linked to heat tolerance to determine whether infrared thermography temperatures were able to separate groups of animals and determine the most important variables in this differentiation. Forty-eight four-month-old male lambs from eight genetic groups were used. Physiological (rectal temperature–RT, heart rate–HR, respiratory rate–RR and blood traits, infrared thermography temperatures, heat tolerance indices, body measurements, weight and carcass traits were measured. Statistical analyses included variance, correlations, factor, discrimination and regression. Observing the correlations between physiological characteristics (RT, RR and HR with temperatures measured by infrared thermography, regions for further studies should include the mean temperature of flank, nose and rump. Results show that there are strong relationships between thermograph measurements and RR, RT and HR in lambs, which are suggested to be directly correlated with heat tolerance capacity of the different genetic groups evaluated in this study. The assessment of body surface temperature measured by the thermograph could be used as a noninvasive tool to assess heat tolerance of the animals.

  7. Elevatated CO2 alleviates heat stress tolerance in wheat

    DEFF Research Database (Denmark)

    Kjær, Katrine Heinsvig; Rosenqvist, Eva S. K.; Ottosen, Carl-Otto

    2014-01-01

    Title: The alleviating effect of elevated CO2 on heat stress susceptibility of two wheat (Triticum aestivum L.) cultivars Session: Plant response and adaptation to abiotic stress Sindhuja Shanmugam1, Katrine Heinsvig Kjaer2*, Carl-Otto Ottosen2, Eva Rosenqvist3, Dew Kumari Sharma3 and Bernd Wolle...... crop performance under various climatic stresses.......Title: The alleviating effect of elevated CO2 on heat stress susceptibility of two wheat (Triticum aestivum L.) cultivars Session: Plant response and adaptation to abiotic stress Sindhuja Shanmugam1, Katrine Heinsvig Kjaer2*, Carl-Otto Ottosen2, Eva Rosenqvist3, Dew Kumari Sharma3 and Bernd......Institute for Agroecology, Aarhus University, Forsøgsvej 1, 4200 Slagelse, Denmark *Presenting author This study analysed the alleviating effect of elevated CO2 on stress-induced decreases in photosynthesis and changes in carbohydrate metabolism in two wheat cultivars (Triticum aestivum L.) of different...

  8. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto

    In prospects of global climate change, heat stress is a rising constraint for the productivity of wheat (Triticum aestivum L.). It is a heat-susceptible crop beyond 17-23oC temperature throughout its phenological stages, flowering phase being the most sensitive stage. Chlorophyll a fluorescence...... parameter, maximum quantum yield efficiency of PSII (Fv/Fm) is used as a physiological marker for early stress detection in PSII in plants. We established a reproducible protocol to measure response of wheat genotypes to high temperature based on Fv/Fm. The heat treatment of 40°C in 300 µmol m-2s-1 PAR...... of 38oC for 2h showed a heritability of 7%. However, a stronger stress at 40oC for 72h in repeated experiments on 138 extreme performing selected genotypes resulted in an increased genetic component of 15% which was further increased to 29% in the third selection cycle with 41 genotypes. Our protocol...

  9. Climate change impacts and potential benefits of heat-tolerant maize in South Asia

    Science.gov (United States)

    Tesfaye, Kindie; Zaidi, P. H.; Gbegbelegbe, Sika; Boeber, Christian; Rahut, Dil Bahadur; Getaneh, Fite; Seetharam, K.; Erenstein, Olaf; Stirling, Clare

    2017-11-01

    Maize is grown by millions of smallholder farmers in South Asia (SA) under diverse environments. The crop is grown in different seasons in a year with varying exposure to weather extremes, including high temperatures at critical growth stages which are expected to increase with climate change. This study assesses the impact of current and future heat stress on maize and the benefit of heat-tolerant varieties in SA. Annual mean maximum temperatures may increase by 1.4-1.8 °C in 2030 and 2.1-2.6 °C in 2050, with large monthly, seasonal, and spatial variations across SA. The extent of heat stressed areas in SA could increase by up to 12 % in 2030 and 21 % in 2050 relative to the baseline. The impact of heat stress and the benefit from heat-tolerant varieties vary with the level of temperature increase and planting season. At a regional scale, climate change would reduce rainfed maize yield by an average of 3.3-6.4 % in 2030 and 5.2-12.2 % in 2050 and irrigated yield by 3-8 % in 2030 and 5-14 % in 2050 if current varieties were grown under the future climate. Under projected climate, heat-tolerant varieties could minimize yield loss (relative to current maize varieties) by up to 36 and 93 % in 2030 and 33 and 86 % in 2050 under rainfed and irrigated conditions, respectively. Heat-tolerant maize varieties, therefore, have the potential to shield maize farmers from severe yield loss due to heat stress and help them adapt to climate change impacts.

  10. Heat tolerance of dairy lactococcal c2 phages

    DEFF Research Database (Denmark)

    Nielsen, Cecilie Lykke Marvig; Basheer, Aideh; Neve, H.

    2011-01-01

    Nine Lactococcus lactis c2 phages propagated on different hosts were screened for thermal resistance in skimmed milk. Pronounced variations in thermal resistance were found. Three phages displayed high sensitivity towards heat resulting in >8 log reductions after 70 °C for 5 min, whereas the most...... thermal resistant phages required 80 °C for 5 min to obtain the same reduction. Inactivation kinetics were determined for a thermo-sensitive and a thermo-resistant phage at 60–70 °C and 65–78 °C, respectively, using a submerged-coil system with extremely short heating-up times. Inactivation followed first......-order kinetics with correlation coefficients of 0.96–0.99. D70-values of 12 s and 16.6 min were calculated for the most sensitive and resistant phage, respectively. Release of phage DNA from capsids, and disintegration of phage heads and tails were among the first morphological changes observed for moderately...

  11. Development of late blight resistance and heat tolerance through gamma irradiation of shoot cultures in potato

    International Nuclear Information System (INIS)

    Gosal, S.S.; Jitender Kaur, Adas; Minocha, J.L.

    2001-01-01

    In vitro shoot cultures of two potato varieties viz., Kufri jyoti and Kufri Chandramukhi were gamma irradiated at 20 Gy and 40 Gy. Micro tubers were induced in micro propagated M1V3 generation. For heat tolerance micro tubers were induced at elevated (28 C ) incubation temperature (optimum being 20 1C ) and were characterized by early sowing, chlorophyll persistence and harvest index. The number of micro tubers/plant was highly reduced at elevated temperature and the resulting tubers exhibited distorted shapes and growth of apical buds. Thus obtained micro tubers exhibited better germination (62.3%) even in early sowing at relatively higher temperature. The progenies from putative heat tolerant plants were grown in the field by sowing at higher temperature for four subsequent generations. Heat tolerant plants segregated in each generation but the frequency of heat tolerant plants increased in the advanced generation. For developing late blight resistance micro tubers produced from irradiated shoot cultures were sown in pots and resulting plants were screened using detached leaf method. The progenies of putative resistant plants grown in the field were artificially inoculated with sporangial inoculum of Phytophthora infection's. Field grown plants exhibited segregation with respect to disease reaction and about 56 per cent plants showed resistance. Segregation was reduced during following generation and the frequency of resistant plants was increased up to 72.3 per cent. Thus, repeated selections has helped in developing stable mutants in both the varieties

  12. Complex patterns of geographic variation in heat tolerance and Hsp70 expression levels in the common frog Rana temporaria

    DEFF Research Database (Denmark)

    Sørensen, Jesper Givskov; Pekkonen, Minna; Lindgren, Beatrice

    2009-01-01

    1. We tested for geographical variation in heat tolerance and Hsp70 expression levels of Rana temporaria tadpoles along a 1500 km long latitudinal gradient in Sweden.   2. Temperature tolerance of the hatchling tadpoles did not differ among populations, but they tolerated stressful hot temperatur...

  13. The importance of seed mass for the tolerance to heat shocks of savanna and forest tree species

    NARCIS (Netherlands)

    Ribeiro, L.C.; Barbosa, E.R.M.; Langevelde, van F.; Borghetti, F.

    2015-01-01

    Questions: Does seed mass influence the tolerance of seeds to the effects of heating in fires? Is the tolerance to heat shocks during fire events dependent mostly on seed mass itself or to other traits linked to the species ecological origin, e.g. non-fire-prone (forest) and fire-prone (savanna)

  14. Heat tolerance of automotive lead-acid batteries

    Science.gov (United States)

    Albers, Joern

    Starter batteries have to withstand a quite large temperature range. In Europe, the battery temperature can be -30 °C in winter and may even exceed +60 °C in summer. In most modern cars, there is not much space left in the engine compartment to install the battery. So the mean battery temperature may be higher than it was some decades ago. In some car models, the battery is located in the passenger or luggage compartment, where ambient temperatures are more moderate. Temperature effects are discussed in detail. The consequences of high heat impact into the lead-acid battery may vary for different battery technologies: While grid corrosion is often a dominant factor for flooded lead-acid batteries, water loss may be an additional influence factor for valve-regulated lead-acid batteries. A model was set up that considers external and internal parameters to estimate the water loss of AGM batteries. Even under hot climate conditions, AGM batteries were found to be highly durable and superior to flooded batteries in many cases. Considering the real battery temperature for adjustment of charging voltage, negative effects can be reduced. Especially in micro-hybrid applications, AGM batteries cope with additional requirements much better than flooded batteries, and show less sensitivity to high temperatures than suspected sometimes.

  15. FACTORS AFFECTING HEAT TOLERANCE IN CROSSBRED CATTLE IN CENTRAL BRAZIL

    Directory of Open Access Journals (Sweden)

    Concepta Margaret McManus

    2014-06-01

    Full Text Available This study compared the adaptation traits in common crosses of crossbred dairy cattle in central Brazil. Twenty animals of each of three genetic groups were used: zebu (Bos indicus, Simmental x Zebu (SZ and Holstein x Zebu (HZ. The test measured variations in rectal temperature (RT, respiration rate (RR and heart rate (HR of animals in the shade and after exposure to the sun, as well as mean daily milk production throughout the lactation period. The procedure was repeated three times. There were significant interactions between test group and genetic group for the traits investigated and the correlations among traits were low. The RR of the crossbred groups may be controlling body temperature in such a way as not to cause an increase in RT. Milk production influenced RR in crossbred cows exposed to the sun, confirming their poorer adaptation in comparison with zebu cows. We observed that the adaptation can be measured in terms of production within the same genetic group. In conclusion, the crosses with European breeds produced more milk than zebu, although they were influenced by heat/solar radiation.

  16. Chlorophyll a fluorescence to phenotype wheat genotypes for heat tolerance

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto

    parameter, maximum quantum yield efficiency of PSII (Fv/Fm) is used as a physiological marker for early stress detection in PSII in plants. We established a reproducible protocol to measure response of wheat genotypes to high temperature based on Fv/Fm. The heat treatment of 40°C in 300 µmol m-2s-1 PAR...... for 72h was appropriate to induce genotype dependent variation in Fv/Fm. This standardized protocol was used to phenotype wheat genotypes until the variation in the genotypes was consistently high with increased heritability for the trait, Fv/Fm. Mass screening of 1273 wheat genotypes in a milder stress...... of 38oC for 2h showed a heritability of 7%. However, a stronger stress at 40oC for 72h in repeated experiments on 138 extreme performing selected genotypes resulted in an increased genetic component of 15% which was further increased to 29% in the third selection cycle with 41 genotypes. Our protocol...

  17. Root Antioxidant Mechanisms in Relation to Root Thermotolerance in Perennial Grass Species Contrasting in Heat Tolerance.

    Directory of Open Access Journals (Sweden)

    Yi Xu

    Full Text Available Mechanisms of plant root tolerance to high temperatures through antioxidant defense are not well understood. The objective of this study was to investigate whether superior root thermotolerance of heat-tolerant Agrostis scabra relative to its congeneric heat-sensitive Agrostis stolonifera was associated with differential accumulation of reactive oxygen species and antioxidant scavenging systems. A. scabra 'NTAS' and A. stolonifera 'Penncross' plants were exposed to heat stress (35/30°C, day/night in growth chambers for 24 d. Superoxide (O2(- content increased in both A. stolonifera and A. scabra roots under heat stress but to a far lesser extent in A. scabra than in A. stolonifera. Hydrogen peroxide (H2O2 content increased significantly in A. stolonifera roots but not in A. scabra roots responding to heat stress. The content of antioxidant compounds (ascorbate and glutathione did not differ between A. stolonifera and A. scabra under heat stress. Enzymatic activity of superoxide dismutase was less suppressed in A. scabra than that in A. stolonifera under heat stress, while peroxidase and catalase were more induced in A. scabra than in A. stolonifera. Similarly, their encoded transcript levels were either less suppressed, or more induced in A. scabra roots than those in A. stolonifera during heat stress. Roots of A. scabra exhibited greater alternative respiration rate and lower cytochrome respiration rate under heat stress, which was associated with suppression of O2(- and H2O2 production as shown by respiration inhibitors. Superior root thermotolerance of A. scabra was related to decreases in H2O2 and O2(- accumulation facilitated by active enzymatic antioxidant defense systems and the maintenance of alternative respiration, alleviating cellular damages by heat-induced oxidative stress.

  18. Screening of Pearl Millet F1 Hybrids for Heat Tolerance at Early Seedling Stage

    Directory of Open Access Journals (Sweden)

    Ashok Kumar Yadav

    2014-01-01

    Full Text Available Ten pearl millet genotypes selected on the basis of response to supra-optimal temperature tolerance were crossed in a half-diallel mating system. The 45 F1 hybrids produced were tested along with parents for heat tolerance and related traits at seedling stage. Field screening and laboratory screening techniques were simultaneously used for the evaluation of F1 hybrids and their parents. Heat tolerance was measured as seedling thermotolerance index (STI and seed to seedling thermotolerance index (SSTI under field conditions, but membrane thermostability (MTS in the laboratory. The hybrid H77/29-2 × CVJ-2-5-3-1-3 showed highest STI value followed by H77/833-2 × 96AC-93. The genotype H77/833-2 × 96AC-93 had the highest worth for SSTI. These three indices were highly correlated among themselves. STI values were invariably high, whereas SSTI has lower values, as it also covers the effect of under soil mortality (USM. It was seen that the heat tolerance indices STI and SSTI were not showing any perceptible pooled correlation with developmental traits except germination and emergence rate. Based on our results, it could be suggested that membrane thermostability (MTS may be used for screening large number of genotypes. Field based indices STI and SSTI may be used for evaluation of hybrids and varieties before they are released.

  19. Oligouridylate Binding Protein 1b Plays an Integral Role in Plant Heat Stress Tolerance.

    Science.gov (United States)

    Nguyen, Cam Chau; Nakaminami, Kentaro; Matsui, Akihiro; Kobayashi, Shuhei; Kurihara, Yukio; Toyooka, Kiminori; Tanaka, Maho; Seki, Motoaki

    2016-01-01

    Stress granules (SGs), which are formed in the plant cytoplasm under stress conditions, are transient dynamic sites (particles) for mRNA storage. SGs are actively involved in protecting mRNAs from degradation. Oligouridylate binding protein 1b (UBP1b) is a component of SGs. The formation of microscopically visible cytoplasmic foci, referred to as UBP1b SG, was induced by heat treatment in UBP1b-overexpressing Arabidopsis plants (UBP1b-ox). A detailed understanding of the function of UBP1b, however, is still not clear. UBP1b-ox plants displayed increased heat tolerance, relative to control plants, while ubp1b mutants were more sensitive to heat stress than control plants. Microarray analysis identified 117 genes whose expression was heat-inducible and higher in the UBP1b-ox plants. RNA decay analysis was performed using cordycepin, a transcriptional inhibitor. In order to determine if those genes serve as targets of UBP1b, the rate of RNA degradation of a DnaJ heat shock protein and a stress-associated protein (AtSAP3) in UBP1b-ox plants was slower than in control plants; indicating that the mRNAs of these genes were protected within the UBP1b SG granule. Collectively, these data demonstrate that UBP1b plays an integral role in heat stress tolerance in plants.

  20. Heat priming induces trans-generational tolerance to high temperature stress in wheat

    Directory of Open Access Journals (Sweden)

    Xiao eWang

    2016-04-01

    Full Text Available Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH, the progeny of heat-primed plants (PH possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the transcriptome profile, 1430 probes showed obvious difference in expression between PH and NH. These genes were related to signal transduction, transcription, energy, defense, and protein destination and storage, respectively. The gene encoding the lysine-specific histone demethylase 1 (LSD1 which was involved in histone demethylation related to epigenetic modification was up-regulated in the PH compared with NH. The proteome analysis indicated that the proteins involved in photosynthesis, energy production and protein destination and storage were up-regulated in the PH compared with NH. In short, thermos-tolerance was induced through heritable epigenetic alternation and signaling transduction, both processes further triggered prompt modifications of defense related responses in anti-oxidation, transcription, energy production, and protein destination and storage in the progeny of the primed plants under high temperature stress. It was concluded that trans-generation thermo-tolerance was induced by heat priming in the first generation, and this might be an effective measure to cope with severe high-temperature stresses during key growth stages in wheat production.

  1. Heat Priming Induces Trans-generational Tolerance to High Temperature Stress in Wheat.

    Science.gov (United States)

    Wang, Xiao; Xin, Caiyun; Cai, Jian; Zhou, Qin; Dai, Tingbo; Cao, Weixing; Jiang, Dong

    2016-01-01

    Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH), the progeny of heat-primed plants (PH) possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the transcriptome profile, 1430 probes showed obvious difference in expression between PH and NH. These genes were related to signal transduction, transcription, energy, defense, and protein destination and storage, respectively. The gene encoding the lysine-specific histone demethylase 1 (LSD1) which was involved in histone demethylation related to epigenetic modification was up-regulated in the PH compared with NH. The proteome analysis indicated that the proteins involved in photosynthesis, energy production and protein destination and storage were up-regulated in the PH compared with NH. In short, thermos-tolerance was induced through heritable epigenetic alternation and signaling transduction, both processes further triggered prompt modifications of defense related responses in anti-oxidation, transcription, energy production, and protein destination and storage in the progeny of the primed plants under high temperature stress. It was concluded that trans-generation thermo-tolerance was induced by heat priming in the first generation, and this might be an effective measure to cope with severe high-temperature stresses during key growth stages in wheat production.

  2. Tolerance

    DEFF Research Database (Denmark)

    Tønder, Lars

    Tolerance: A Sensorial Orientation to Politics is an experiment in re-orientation. The book is based on the wager that tolerance exceeds the more prevalent images of self-restraint and repressive benevolence because neither precludes the possibility of a more “active tolerance” motivated...... by the desire to experiment and to become otherwise. The objective is to discuss what gets lost, conceptually as well as politically, when we neglect the subsistence of active tolerance within other practices of tolerance, and to develop a theory of active tolerance in which tolerance's mobilizing character...... the current models of restraint and benevolence, other ways of understanding the politics of democratic pluralism might be developed, which will enable us to conceive of tolerance's future in terms different than those currently on offer. Tolerance: A Sensorial Orientation to Politics develops...

  3. Overexpression of Arabidopsis P3B increases heat and low temperature stress tolerance in transgenic sweetpotato.

    Science.gov (United States)

    Ji, Chang Yoon; Jin, Rong; Xu, Zhen; Kim, Ho Soo; Lee, Chan-Ju; Kang, Le; Kim, So-Eun; Lee, Hyeong-Un; Lee, Joon Seol; Kang, Chang Ho; Chi, Yong Hun; Lee, Sang Yeol; Xie, Yiping; Li, Hongmin; Ma, Daifu; Kwak, Sang-Soo

    2017-08-14

    Sweetpotato (Ipomoea batatas [L.] Lam) is suitable for growth on marginal lands due to its abiotic stress tolerance. However, severe environmental conditions including low temperature pose a serious threat to the productivity and expanded cultivation of this crop. In this study, we aimed to develop sweetpotato plants with enhanced tolerance to temperature stress. P3 proteins are plant-specific ribosomal P-proteins that act as both protein and RNA chaperones to increase heat and cold stress tolerance in Arabidopsis. Here, we generated transgenic sweetpotato plants expressing the Arabidopsis ribosomal P3 (AtP3B) gene under the control of the CaMV 35S promoter (referred to as OP plants). Three OP lines (OP1, OP30, and OP32) were selected based on AtP3B transcript levels. The OP plants displayed greater heat tolerance and higher photosynthesis efficiency than wild type (WT) plants. The OP plants also exhibited enhanced low temperature tolerance, with higher photosynthesis efficiency and less membrane permeability than WT plants. In addition, OP plants had lower levels of hydrogen peroxide and higher activities of antioxidant enzymes such as peroxidase and catalase than WT plants under low temperature stress. The yields of tuberous roots and aerial parts of plants did not significantly differ between OP and WT plants under field cultivation. However, the tuberous roots of OP transgenic sweetpotato showed improved storage ability under low temperature conditions. The OP plants developed in this study exhibited increased tolerance to temperature stress and enhanced storage ability under low temperature compared to WT plants, suggesting that they could be used to enhance sustainable agriculture on marginal lands.

  4. Roles of Protein Synthesis Elongation Factor EF-Tu in Heat Tolerance in Plants

    Directory of Open Access Journals (Sweden)

    Jianming Fu

    2012-01-01

    Full Text Available EF-Tu proteins of plastids, mitochondria, and the cytosolic counterpart EF-1α in plants, as well as EF-Tu proteins of bacteria, are highly conserved and multifunctional. The functions of EF-Tu include transporting the aminoacyl-tRNA complex to the A site of the ribosome during protein biosynthesis; chaperone activity in protecting other proteins from aggregation caused by environmental stresses, facilitating renaturation of proteins when conditions return to normal; displaying a protein disulfide isomerase activity; participating in the degradation of N-terminally blocked proteins by the proteasome; eliciting innate immunity and triggering resistance to pathogenic bacteria in plants; participating in transcription when an E. coli host is infected with phages. EF-Tu genes are upregulated by abiotic stresses in plants, and EF-Tu plays important role in stress responses. Expression of a plant EF-Tu gene confers heat tolerance in E. coli, maize knock-out EF-Tu null mutants are heat susceptible, and over-expression of an EF-Tu gene improves heat tolerance in crop plants. This review paper summarizes the current knowledge of EF-Tu proteins in stress responses in plants and progress on application of EF-Tu for developing crop varieties tolerant to abiotic stresses, such as high temperatures.

  5. Development of a new heat tolerance index for selecting productive goats for the tropics

    International Nuclear Information System (INIS)

    Kamal, T.H.; Mostafa, S.I.; Habib, A.A.; Elmasry, A.M.; Abdelsamee, A.M.; Abolnaga, A.I.; Kassab, F.A.; Abdelhamid, A.M.

    1988-01-01

    A heat tolerance index previously developed in cattle was verified in two breeds of goats to identify young heat tolerant animals capable of maintaining liveweight and milk yield on exposure to high environmental temperatures. Twelve Baladi and Bedouin goats were divided into two equal groups and offered either river or salt water (1.8% Mediterranean sea salt). The animals were maintained in climatic chambers at 18 deg. C and 70% RH for an initial four day period followed by another four days at 38 deg. C and 50% RH for seven hours per day. On the second day of each period, each animal was injected intravenously with tritiated water and total body water (TBW) determined. The percentage increase in TBW induced by the high temperature treatment was subtracted from 100 and the TBW heat tolerance index (HTI) was calculated. TBW-HTI correlated significantly with the percentage increase in live body weight (LBW) in goats over a three month exposure to heat stress and with the percentage decrease in daily milk yield over a seven day heat exposure period. TBW-HTI averages of Baladi and Bedouin goats drinking river water were 81 and 88 respectively while those drinking salt water were 86 and 92 respectively. The equations for the predicted percentage increase in liveweight (Y) in a hot environment for Baladi and Bedouin goats were Y = -38.56 + 0.728X and Y = -45.27 + 0.622X respectively, where X is the TBW-HTI index; the predicted percentage decrease in milk yield in a hot environment Y for all goats was Y = 142.28-1.339X. (author). 9 refs, 1 fig., 5 tabs

  6. Physiological and molecular evidence of differential short-term heat tolerance in Mediterranean seagrasses

    Science.gov (United States)

    Marín-Guirao, Lazaro; Ruiz, Juan M.; Dattolo, Emanuela; Garcia-Munoz, Rocio; Procaccini, Gabriele

    2016-06-01

    The increase in extreme heat events associated to global warming threatens seagrass ecosystems, likely by affecting key plant physiological processes such as photosynthesis and respiration. Understanding species’ ability to acclimate to warming is crucial to better predict their future trends. Here, we study tolerance to warming in two key Mediterranean seagrasses, Posidonia oceanica and Cymodocea nodosa. Stress responses of shallow and deep plants were followed during and after short-term heat exposure in mesocosms by coupling photo-physiological measures with analysis of expression of photosynthesis and stress-related genes. Contrasting tolerance and capacity to heat acclimation were shown by shallow and deep P. oceanica ecotypes. While shallow plants acclimated through respiratory homeostasis and activation of photo-protective mechanisms, deep ones experienced photosynthetic injury and impaired carbon balance. This suggests that P. oceanica ecotypes are thermally adapted to local conditions and that Mediterranean warming will likely diversely affect deep and shallow meadow stands. On the other hand, contrasting mechanisms of heat-acclimation were adopted by the two species. P. oceanica regulates photosynthesis and respiration at the level of control plants while C. nodosa balances both processes at enhanced rates. These acclimation discrepancies are discussed in relation to inherent attributes of the two species.

  7. The heat is on: Genetic adaptation to urbanization mediated by thermal tolerance and body size.

    Science.gov (United States)

    Brans, Kristien I; Jansen, Mieke; Vanoverbeke, Joost; Tüzün, Nedim; Stoks, Robby; De Meester, Luc

    2017-12-01

    Worldwide, urbanization leads to tremendous anthropogenic environmental alterations, causing strong selection pressures on populations of animals and plants. Although a key feature of urban areas is their higher temperature ("urban heat islands"), adaptive thermal evolution in organisms inhabiting urban areas has rarely been studied. We tested for evolution of a higher heat tolerance (CT MAX ) in urban populations of the water flea Daphnia magna, a keystone grazer in freshwater ecosystems, by carrying out a common garden experiment at two temperatures (20°C and 24°C) with genotypes of 13 natural populations ordered along a well-defined urbanization gradient. We also assessed body size and haemoglobin concentration to identify underlying physiological drivers of responses in CT MAX . We found a higher CT MAX in animals isolated from urban compared to rural habitats and in animals reared at higher temperatures. We also observed substantial genetic variation in thermal tolerance within populations. Overall, smaller animals were more heat tolerant. While urban animals mature at smaller size, the effect of urbanization on thermal tolerance is only in part caused by reductions in body size. Although urban Daphnia contained higher concentrations of haemoglobin, this did not contribute to their higher CT MAX . Our results provide evidence of adaptive thermal evolution to urbanization in the water flea Daphnia. In addition, our results show both evolutionary potential and adaptive plasticity in rural as well as urban Daphnia populations, facilitating responses to warming. Given the important ecological role of Daphnia in ponds and lakes, these adaptive responses likely impact food web dynamics, top-down control of algae, water quality, and the socio-economic value of urban ponds. © 2017 John Wiley & Sons Ltd.

  8. Exercise increases pressure pain tolerance but not pressure and heat pain thresholds in healthy young men.

    Science.gov (United States)

    Vaegter, H B; Hoeger Bement, M; Madsen, A B; Fridriksson, J; Dasa, M; Graven-Nielsen, T

    2017-01-01

    Exercise causes an acute decrease in the pain sensitivity known as exercise-induced hypoalgesia (EIH), but the specificity to certain pain modalities remains unknown. This study aimed to compare the effect of isometric exercise on the heat and pressure pain sensitivity. On three different days, 20 healthy young men performed two submaximal isometric knee extensions (30% maximal voluntary contraction in 3 min) and a control condition (quiet rest). Before and immediately after exercise and rest, the sensitivity to heat pain and pressure pain was assessed in randomized and counterbalanced order. Cuff pressure pain threshold (cPPT) and pain tolerance (cPTT) were assessed on the ipsilateral lower leg by computer-controlled cuff algometry. Heat pain threshold (HPT) was recorded on the ipsilateral foot by a computer-controlled thermal stimulator. Cuff pressure pain tolerance was significantly increased after exercise compared with baseline and rest (p exercise. No significant correlation between exercise-induced changes in HPT and cPPT was found. Test-retest reliability before and after the rest condition was better for cPPT and CPTT (intraclass correlation > 0.77) compared with HPT (intraclass correlation = 0.54). The results indicate that hypoalgesia after submaximal isometric exercise is primarily affecting tolerance of pressure pain compared with the pain threshold. These data contribute to the understanding of how isometric exercise influences pain perception, which is necessary to optimize the clinical utility of exercise in management of chronic pain. The effect of isometric exercise on pain tolerance may be relevant for patients in chronic musculoskeletal pain as a pain-coping strategy. WHAT DOES THIS STUDY ADD?: The results indicate that hypoalgesia after submaximal isometric exercise is primarily affecting tolerance of pressure pain compared with the heat and pressure pain threshold. These data contribute to the understanding of how isometric exercise

  9. Physiological, Biochemical, and Molecular Mechanisms of Heat Stress Tolerance in Plants

    Science.gov (United States)

    Hasanuzzaman, Mirza; Nahar, Kamrun; Alam, Md. Mahabub; Roychowdhury, Rajib; Fujita, Masayuki

    2013-01-01

    High temperature (HT) stress is a major environmental stress that limits plant growth, metabolism, and productivity worldwide. Plant growth and development involve numerous biochemical reactions that are sensitive to temperature. Plant responses to HT vary with the degree and duration of HT and the plant type. HT is now a major concern for crop production and approaches for sustaining high yields of crop plants under HT stress are important agricultural goals. Plants possess a number of adaptive, avoidance, or acclimation mechanisms to cope with HT situations. In addition, major tolerance mechanisms that employ ion transporters, proteins, osmoprotectants, antioxidants, and other factors involved in signaling cascades and transcriptional control are activated to offset stress-induced biochemical and physiological alterations. Plant survival under HT stress depends on the ability to perceive the HT stimulus, generate and transmit the signal, and initiate appropriate physiological and biochemical changes. HT-induced gene expression and metabolite synthesis also substantially improve tolerance. The physiological and biochemical responses to heat stress are active research areas, and the molecular approaches are being adopted for developing HT tolerance in plants. This article reviews the recent findings on responses, adaptation, and tolerance to HT at the cellular, organellar, and whole plant levels and describes various approaches being taken to enhance thermotolerance in plants. PMID:23644891

  10. Physiological, biochemical, and molecular mechanisms of heat stress tolerance in plants.

    Science.gov (United States)

    Hasanuzzaman, Mirza; Nahar, Kamrun; Alam, Md Mahabub; Roychowdhury, Rajib; Fujita, Masayuki

    2013-05-03

    High temperature (HT) stress is a major environmental stress that limits plant growth, metabolism, and productivity worldwide. Plant growth and development involve numerous biochemical reactions that are sensitive to temperature. Plant responses to HT vary with the degree and duration of HT and the plant type. HT is now a major concern for crop production and approaches for sustaining high yields of crop plants under HT stress are important agricultural goals. Plants possess a number of adaptive, avoidance, or acclimation mechanisms to cope with HT situations. In addition, major tolerance mechanisms that employ ion transporters, proteins, osmoprotectants, antioxidants, and other factors involved in signaling cascades and transcriptional control are activated to offset stress-induced biochemical and physiological alterations. Plant survival under HT stress depends on the ability to perceive the HT stimulus, generate and transmit the signal, and initiate appropriate physiological and biochemical changes. HT-induced gene expression and metabolite synthesis also substantially improve tolerance. The physiological and biochemical responses to heat stress are active research areas, and the molecular approaches are being adopted for developing HT tolerance in plants. This article reviews the recent findings on responses, adaptation, and tolerance to HT at the cellular, organellar, and whole plant levels and describes various approaches being taken to enhance thermotolerance in plants.

  11. Rye (Secale cereale) supernumerary (B) chromosomes associated with heat tolerance during early stages of male sporogenesis

    Science.gov (United States)

    Pereira, H. Sofia; Delgado, Margarida; Viegas, Wanda; Rato, João M.; Barão, Augusta; Caperta, Ana D.

    2017-01-01

    Background and aims Rye supernumerary (B) chromosomes have an accumulation mechanism involving the B subtelomeric domain highly enriched in D1100- and E3900-related sequences. In this work, the effects of heat stress during the early stages of male meiosis in 0B and +B plants were studied. Methods In-depth cytological analyses of chromatin structure and behaviour were performed on staged rye meiocytes utilizing DAPI, fluorescence in situ hybridization and 5-methylcytosine immune labelling. Quantitative real-time PCR was used to measure heat effects on the expression of the Hsp101 gene as well as the 3·9- and 2·7-kb E3900 forms in various tissues and meiotic stages. Key Results and Conclusions Quantitative real-time PCR established that heat induced equal up-regulation of the Hsp101 gene in 0B and 2B plants, with a marked peak in anthers with meiocytes staged at pachytene. Heat also resulted in significant up-regulation of E3900-related transcripts, especially at pachytene and for the truncated 2·7-kb form of E3900. Cytological heat-induced anomalies in prophase I, measured as the frequency of anomalous meiocytes, were significantly greater in 0B plants. Whereas telomeric sequences were widely distributed in a manner close to normal in the majority of 2B pachytene cells, most 0B meiocytes displayed abnormally clustered telomeres after chromosome pairing had occurred. Relevantly, bioinformatic analysis revealed a significantly high-density heat responsive cis regulatory sequence on E3900, clearly supporting stress-induced response of transcription for the truncated variant. Taken together, these results are the first indication that rye B chromosomes have implications on heat tolerance and may protect meiocytes against heat stress-induced damage. PMID:27818381

  12. Enhanced heat tolerance in transgenic silkworm via overexpression of Pyrococcus furiosus superoxide reductase.

    Science.gov (United States)

    Jiang, Liang; Huang, Chunlin; Wang, Bingbing; Guo, Huizhen; Sun, Qiang; Xia, Fei; Xu, Guowen; Xia, Qingyou

    2018-01-01

    Heat shock causes a serious harm to organisms by accelerating the production of reactive oxygen species (ROS). Pyrococcus furiosus superoxide reductase (PfSOR) is an enzyme that efficiently detoxifies ROS. In order to generate a silkworm strain with high heat tolerance for sericulture, we synthesized an artificial DNA sequence encoding PfSOR based on the codon bias of Bombyx mori. PfSOR was successfully overexpressed in transgenic silkworm (named A4SOR) and BmE cells, as determined by RT-PCR and western blot analyses. An SOR activity assay confirmed that the expressed enzyme was functional in A4SOR. After exposure to a temperature of 35 °C for 44 h, the mortality rate was about 30% lower in transgenic A4SOR than in non-transgenic silkworms. Moreover, transgene expression had no apparent effect on economic characteristics of silkworms. The heat tolerance of silkworm was thus enhanced by expressing an archaeal SOR; this can be useful for sericulture in regions where the average temperature exceeds the optimal environmental temperature for B. mori of 25 °C. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Plant tolerance to high temperature in a changing environment: scientific fundamentals and production of heat stress tolerant crops

    Directory of Open Access Journals (Sweden)

    Craita eBita

    2013-07-01

    Full Text Available Global warming is predicted to have a general negative effect on plant growth due to the negative effect of high temperatures on plant development. The increasing threat of climatological extremes, including very high temperatures might lead to catastrophic loss of crop productivity and result in wide spread famine. In this review we assess the impact of global climate change on the production of agricultural crop production. There is a differential effect of climate change both in terms of geographic location and the crops that have will be likely to show the most extreme reductions in yield as a result of warming in general and the expected fluctuations in temperature. High temperature stress has a wide range of effects on plants both in terms of physiology, biochemistry and gene regulation pathways. In this review we present the recent advances of research on all these level of investigation focusing on potential leads that may help to understand more fully the mechanisms that make plants tolerant or susceptible to heat stress. Finally we review possible mechanisms and methods which can lead to the generation of new varieties that will allow sustainable yield production in a world likely to be challenged both by increasing population, higher average temperatures and larger temperature fluctuations.

  14. Our winters of discontent : addressing the problem of rising home heating costs

    International Nuclear Information System (INIS)

    Hughes, L.; Wysocki, A.

    2006-03-01

    The cost of space heating may soon increase due to rising fuel prices in international energy markets and the absence of federal and provincial energy security policies. This report examined the benefits and disadvantages of 2 approaches to assist those with limited incomes to meet heating requirements: (1) offering Low Income Fuel Assistance (LIFA) as a one-time payment during the heating season; and (2) the elimination of taxes for home heating fuels. The cost of home heating fuels and their impacts on consumers and governments were considered. A review of the Nova Scotia government's Keep the Heat program noted that the program was not responsive to increases in the price of home heating fuel, particularly if increases in a year exceeded the level of assistance. It was suggested that the removal of heating sales taxes could provide unnecessary windfalls to households with large homes, as well as windfall profits for landlords if savings were not passed on to tenants. Using Nova Scotia as a case study, an alternative support system was considered that guaranteed a set price for heating fuel for those in need. It was suggested that this approach could cost less than a lump-sum payment or the elimination of taxes on home-heating fuel. In addition, the approach would provide low-income consumers with predictable and affordable prices. It was concluded that as space heating energy costs continue to rise, all government fuel assistance programs run the risk of becoming larger and more costly. Other solutions included reducing Canada's dependence on fossil fuels through the use of solar energy; the reduction of residential energy demand; and the promotion of district heating. 26 refs., 9 tabs., 3 figs

  15. Heat tolerance in Field Grown Tomatoes (Lycopersicon esculentum Mill.) under Semi Arid Conditions of West Africa

    DEFF Research Database (Denmark)

    Kugblenu, Y O; Oppong Danso, E; Ofori, K

    2013-01-01

    to October, which has a mean temperature of 23°C. Heat tolerant tomato cultivars were grown from April to July with a mean temperature of 25°C to evaluate their performance under these conditions and to assess the effect of shading on the production of one of the genotypes. Fruiting percentage...... was significantly lower in exotic hybrids compared to a local variety. Different genotypes showed no differences in the production of viable pollen. Shading decreased final shoot and root biomass by 67 and 47%, respectively, whiles fruit yield was not affected. Also among cultivars yields were similar....

  16. Cold activity and tolerance of the entomopathogenic fungus Tolypocladium spp. to UV-B irradiation and heat.

    Science.gov (United States)

    Santos, Maiara P; Dias, Luciana P; Ferreira, Paulo C; Pasin, Liliana A A P; Rangel, Drauzio E N

    2011-11-01

    Studies on the stress resistance of insect-pathogenic fungi are very important to better understand the survival of these organisms in the environment. In this study, we examined the cold activity (8 ± 1°C for 7 days), UV-B tolerance (Quaite-weighted UV-B irradiance at 847.90 mW m(-2) for 1, 2, 3, and 4 h), and wet-heat tolerance (45°C for 1, 2, 3, and 4 h) of two isolates of Tolypocladiumcylindrosporum (ARSEF 3392 and 5558), one isolate of Tolypocladium geodes (ARSEF 3275), and two isolates of Tolypocladium inflatum (ARSEF 4772 and 4877) based on their germination, compared with Metarhizium robertsii (ARSEF 2575). After 3 h of UV-B exposure, T. cylindrosporum germinated at a greater rate than the other Tolypocladium species and had similar viability to that of the M. robertsii. Most Tolypocladium isolates, however, were less UV-B tolerant than M. robertsii. The T.cylindrosporum isolates were also the most thermotolerant, with similar tolerance to the M. robertsii. The isolates of T. inflatum and T. geodes, which had similar heat tolerance, were the least heat tolerant compared with the isolates of T. cylindrosporum and M. robertsii. After 4h of heat exposure, the germination of T. inflatum and T. geodes isolates was not significantly different. For cold activity, both T.cylindrosporum isolates germinated to ca. 100% in only 3 days. Approximately 50% of the two T. inflatum isolates germinated, and less than 5% of T. geodes germinated after 3 days. All fungal isolates, however, completely germinated by the seventh day, except M.robertsii. The isolates of T. cylindrosporum, therefore, were the most heat and UV-B tolerant, and had the highest cold activity compared to the other species. The tolerance of M. robertsii to UV-B radiation and heat was similar to that of T.cylindrosporum. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Investigating inbreeding depression for heat stress tolerance in the model organism Drosophila melanogaster

    DEFF Research Database (Denmark)

    Pedersen, Kamilla Sofie; Pedersen, Louise Dybdahl; Sørensen, Anders Christian

    2012-01-01

    Mating between closely related individuals often causes reduced fitness, which is termed ‘inbreeding depression’. Inbreeding is, therefore, a threat towards the persistence of animal and plant populations. Here we present methods and results from a practical for high-school and first-year univers......Mating between closely related individuals often causes reduced fitness, which is termed ‘inbreeding depression’. Inbreeding is, therefore, a threat towards the persistence of animal and plant populations. Here we present methods and results from a practical for high-school and first...... into vials before exposure to 38°C heat stress in a water bath for 1 h. Half an hour later the number of comatose inbred and control flies were scored and chi-square statistic procedures were used to test for different degrees of heat stress tolerance between the two lines of flies. The practical introduces...

  18. Heat tolerance of Salmonella enterica serovars Agona, Enteritidis, and Typhimurium in peanut butter.

    Science.gov (United States)

    Shachar, Dina; Yaron, Sima

    2006-11-01

    Recent large foodborne outbreaks caused by Salmonella enterica serovars have been associated with consumption of foods with high fat content and reduced water activity, even though their ingredients usually undergo pasteurization. The present study was focused on the heat tolerance of Salmonella enterica serovars Agona, Enteritidis, and Typhimurium in peanut butter. The Salmonella serovars in the peanut butter were resistant to heat, and even at a temperature as high as 90 degrees C only 3.2-log reduction in CFU was observed. The obtained thermal inactivation curves were upwardly concave, indicating rapid death at the beginning (10 min) followed by lower death rates and an asymptotic tail. The curves fitted the nonlinear Weibull model with beta parameters pasteurization process cannot be improved significantly by longer treatment or higher temperatures.

  19. Competition magnifies the impact of a pesticide in a warming world by reducing heat tolerance and increasing autotomy.

    Science.gov (United States)

    Op de Beeck, Lin; Verheyen, Julie; Stoks, Robby

    2018-02-01

    There is increasing concern that standard laboratory toxicity tests may be misleading when assessing the impact of toxicants, because they lack ecological realism. Both warming and biotic interactions have been identified to magnify the effects of toxicants. Moreover, while biotic interactions may change the impact of toxicants, toxicants may also change the impact of biotic interactions. However, studies looking at the impact of biotic interactions on the toxicity of pesticides and vice versa under warming are very scarce. Therefore, we tested how warming (+4 °C), intraspecific competition (density treatment) and exposure to the pesticide chlorpyrifos, both in isolation and in combination, affected mortality, cannibalism, growth and heat tolerance of low- and high-latitude populations of the damselfly Ischnura elegans. Moreover, we addressed whether toxicant exposure, potentially in interaction with competition and warming, increased the frequency of autotomy, a widespread antipredator mechanism. Competition increased the toxicity of chlorpyrifos and made it become lethal. Cannibalism was not affected by chlorpyrifos but increased at high density and under warming. Chlorpyrifos reduced heat tolerance but only when competition was high. This is the first demonstration that a biotic interaction can be a major determinant of 'toxicant-induced climate change sensitivity'. Competition enhanced the impact of chlorpyrifos under warming for high-latitude larvae, leading to an increase in autotomy which reduces fitness in the long term. This points to a novel pathway how transient pesticide pulses may cause delayed effects on populations in a warming world. Our results highlight that the interplay between biotic interactions and toxicants have a strong relevance for ecological risk assessment in a warming polluted world. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. The effect of acclimation on heat tolerance of Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae).

    Science.gov (United States)

    Li, Meng; Li, Xiao-Juan; Lü, Jian-Hua; Huo, Ming-Fei

    2018-01-01

    Lasioderma serricorne (Fabricius) (Coleoptera: Anobiidae) is an important economic insect of various stored products worldwide. With the restricted use of methyl bromide and the increasing negative effects of repeated use of phosphine fumigation, heat treatment becomes the main approach to control stored-product insects. We investigated effect of the acclimation to sublethal high temperature of 36°C and 42°C for different times on heat tolerance of L. serricorne adults, pupae, larvae, and eggs to lethal high temperature of 50°C in laboratory. The acclimation of L. serricorne pupae, larvae, and eggs, but not adults, to 36°C improved their survival when exposed to lethal high temperature of 50°C. The acclimation of all life stages of L. serricorne to 42°C significantly improved their survival when exposed to 50°C. For eggs, larvae, and adults, the protective effectiveness of acclimation to 42°C was much more profound than that of to 36°C. LT 50 and LT 90 of all life stages increased with increasing acclimation time to 42°C in general. The LT 50 of L. serricorne adults, pupae, larvae, and eggs acclimation to 42°C for 20h were 2.2, 2.2, 3.4, and 4.8 times higher than that of insects without acclimation, respectively. The results suggest that acclimation to sublethal high temperatures can significantly improve the heat tolerance of L. serricorne by the means of increasing their survival when confronting lethal high temperatures. In the face of global warming, the protective effects induced by acclimation to sublethal high temperatures should be fully considered when design or apply heat treatment to control L. serricorne. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Molecular programs induced by heat acclimation confer neuroprotection against TBI and hypoxic insults via cross-tolerance mechanisms

    Directory of Open Access Journals (Sweden)

    Michal eHorowitz

    2015-07-01

    Full Text Available Neuroprotection following prolonged exposure to high ambient temperatures (heat acclimation HA develops via altered molecular programs such as cross-tolerance (Heat Acclimation -Neuroprotection Cross-Tolerance -HANCT. The mechanisms underlying cross-tolerance depend on enhanced on-demand protective pathways evolving during acclimation. The protection achieved is long lasting and limits the need for de novo recruitment of cytoprotective pathways upon exposure to novel stressors. Using mouse and rat acclimated phenotypes, we will focus on the impact of heat acclimation on Angiotensin II-AT2 receptors in neurogenesis and on HIF-1 as key mediators in spontaneous recovery and HANCT after traumatic brain injury (TBI. The neuroprotective consequences of heat acclimation on NMDA and AMPA receptors will be discussed using the global hypoxia model. A behavioral-molecular link will be crystallized. The differences between HANCT and consensus preconditioning will be reviewed.

  2. Physiological tolerance to uncompensated heat stress in soldiers: effects of various types of body cooling systems.

    Science.gov (United States)

    Jovanović, Dalibor; Karkalić, Radovan; Zeba, Snjezana; Pavlović, Miroslav; Radaković, Sonja S

    2014-03-01

    In military services, emergency situations when soldiers are exposed to a combination of nuclear, biological and chemical (NBC) contamination combined with heat stress, are frequent and complex. In these specific conditions, usage of personal body cooling systems may be effective in reducing heat stress. The present study was conducted in order to evaluate the efficiency of four various types of contemporary personal body cooling systems based on the "Phase Change Material" (PCM), and its effects on soldiers' subjective comfort and physiological performance during exertional heat stress in hot environments. Ten male soldiers were voluntarily subjected to exertional heat stress tests (EHSTs) consisted of walking on a treadmill (5.5 km/h) in hot conditions (40 degreesC) in climatic chamber, wearing NBC isolating impermeable protective suits. One of the tests was performed without any additional cooling solution (NOCOOL), and four tests were performed while using different types of cooling systems: three in a form of vests and one as underwear. Physiological strain was determined by the mean skin temperature (Tsk), tympanic temperature (Tty), and heart rate values (HR), while sweat rates (SwR) indicated changes in hydration status. In all the cases EHST induced physiological response manifested through increasing Tty, HR and SwR. Compared to NOCOOL tests, when using cooling vests, Tty and Tsk were significantly lower (on 35th min, for 0.44 +/- 0.03 and 0.49 +/- 0.05 degrees C, respectively; p stress manifested by increased core and skin temperatures and heart rate values. These effects directly improve heat tolerance, hydration state, decrease in the risk of heat illness, and extends the duration of soldiers' exposure to extreme conditions.

  3. Hydrogen peroxide mediates abscisic acid-induced HSP70 accumulation and heat tolerance in grafted cucumber plants.

    Science.gov (United States)

    Li, Hao; Liu, Shan-Shan; Yi, Chang-Yu; Wang, Feng; Zhou, Jie; Xia, Xiao-Jian; Shi, Kai; Zhou, Yan-Hong; Yu, Jing-Quan

    2014-12-01

    Root-shoot communications play important roles in plant stress responses. Here, we examined the roles of root-sourced signals in the shoot response to heat in cucumber plants. Cucumber plants grafted onto their own roots and luffa roots were exposed to aerial and root-zone heat to examine their tolerance by assessing the levels of oxidative stress, PSII photoinhibition, accumulation of abscisic acid (ABA), H2 O2 and heat shock protein (HSP) 70 using immunoblotting, chlorophyll fluorescence, immunoassay, CeCl3 staining and Western blotting, respectively. Grafting onto the luffa rootstock enhanced the shoot tolerance to the heat. This enhanced tolerance was associated with increased accumulation of ABA and apoplastic H2 O2 , RBOH transcripts and HSP70 expression and a decrease in oxidative stress in the shoots. The increases in the ABA and H2 O2 concentrations in the shoots were attributed to an increase in ABA transport from roots and an increase in ABA biosynthesis in the shoots when the root-zone and shoots were heat stressed, respectively. Inhibition of H2 O2 accumulation compromised luffa rootstock-induced HSP70 expression and heat tolerance. These results suggest that, under heat stress, ABA triggers the expression of HSP70 in an apoplastic H2 O2 -dependent manner, implicating the role of an ABA-dependent H2 O2 -driven mechanism in a systemic response involving root-shoot communication. © 2014 John Wiley & Sons Ltd.

  4. Nitric oxide production and tolerance differ among Symbiodinium types exposed to heat stress.

    Science.gov (United States)

    Hawkins, Thomas D; Davy, Simon K

    2012-11-01

    Nitric oxide (NO) is a ubiquitous molecule and its involvement in metazoan-microbe symbiosis is well known. Evidence suggests that it plays a role in the temperature-induced breakdown ('bleaching') of the ecologically important cnidarian-dinoflagellate association, and this can often lead to widespread mortality of affected hosts. This study confirms that dinoflagellates of the genus Symbiodinium can produce NO and that production of the compound is differentially regulated in different types when exposed to elevated temperature. Temperature-sensitive type B1 cells under heat stress (8°C above ambient) exhibited significant increases in NO synthesis, which occurred alongside pronounced photoinhibition and cell mortality. Tolerant type A1 cells also displayed increases in NO production, yet maintained photosynthetic yields at levels similar to those of untreated cells and displayed less dramatic increases in cell death. Type C1 cells displayed a down-regulation of NO synthesis at high temperature, and no significant mortality increases were observed in this type. Temperature-induced mortality in types A1 and B1 was affected by the prevailing level of NO and, furthermore, photosynthetic yields of these temperature-tolerant and -sensitive types appeared differentially susceptible to NO donated by pharmacological agents. Taken together, these differences in NO synthesis and tolerance could potentially influence the varying bleaching responses seen among hosts harboring different Symbiodinium types.

  5. Modulation of Antioxidant Defense System Is Associated with Combined Drought and Heat Stress Tolerance in Citrus

    Directory of Open Access Journals (Sweden)

    Sara I. Zandalinas

    2017-06-01

    Full Text Available Drought and high temperatures are two major abiotic stress factors that often occur simultaneously in nature, affecting negatively crop performance and yield. Moreover, these environmental challenges induce oxidative stress in plants through the production of reactive oxygen species (ROS. Carrizo citrange and Cleopatra mandarin are two citrus genotypes with contrasting ability to cope with the combination of drought and heat stress. In this work, a direct relationship between an increased antioxidant activity and stress tolerance is reported. According to our results, the ability of Carrizo plants to efficiently coordinate superoxide dismutase (SOD, ascorbate peroxidase (APX, catalase (CAT, and glutathione reductase (GR activities involved in ROS detoxification along with the maintenance of a favorable GSH/GSSG ratio could be related to their relative tolerance to this stress combination. On the other hand, the increment of SOD activity and the inefficient GR activation along with the lack of CAT and APX activities in Cleopatra plants in response to the combination of drought and heat stress, could contribute to an increased oxidative stress and the higher sensibility of this citrus genotype to this stress combination.

  6. Modulation of Antioxidant Defense System Is Associated with Combined Drought and Heat Stress Tolerance in Citrus.

    Science.gov (United States)

    Zandalinas, Sara I; Balfagón, Damián; Arbona, Vicent; Gómez-Cadenas, Aurelio

    2017-01-01

    Drought and high temperatures are two major abiotic stress factors that often occur simultaneously in nature, affecting negatively crop performance and yield. Moreover, these environmental challenges induce oxidative stress in plants through the production of reactive oxygen species (ROS). Carrizo citrange and Cleopatra mandarin are two citrus genotypes with contrasting ability to cope with the combination of drought and heat stress. In this work, a direct relationship between an increased antioxidant activity and stress tolerance is reported. According to our results, the ability of Carrizo plants to efficiently coordinate superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and glutathione reductase (GR) activities involved in ROS detoxification along with the maintenance of a favorable GSH/GSSG ratio could be related to their relative tolerance to this stress combination. On the other hand, the increment of SOD activity and the inefficient GR activation along with the lack of CAT and APX activities in Cleopatra plants in response to the combination of drought and heat stress, could contribute to an increased oxidative stress and the higher sensibility of this citrus genotype to this stress combination.

  7. Small heat shock proteins and the postharvest chilling tolerance of tomato fruit.

    Science.gov (United States)

    Ré, Martín D; Gonzalez, Carla; Escobar, Mariela R; Sossi, María Laura; Valle, Estela M; Boggio, Silvana B

    2017-02-01

    Plants have the largest number of small heat shock proteins (sHsps) (15-42 kDa) among eukaryotes, but little is known about their function in vivo. They accumulate in response to different stresses, and specific sHsps are also expressed during developmental processes such as seed development, germination, and ripening. The presence of organelle-specific sHsps appears to be unique to plants. The sHsps expression is regulated by heat stress transcription factors (Hsfs). In this work, it was explored the role of sHsps in the chilling injury of tomato fruit. The level of transcripts and proteins of cytoplasmic and organellar sHsps was monitored in fruit during ripening and after cold storage (4 weeks at 4°C). Expression of HsfA1, HsfA2, HsfA3, and HsfB1 was also examined. Two cultivars of tomato (Solanum lycopersicum) contrasting in chilling tolerance were assayed: Micro-Tom (chilling-tolerant) and Minitomato (chilling-sensitive). Results showed that sHsps were induced during ripening in fruit from both cultivars. However, sHsps were induced in Micro-Tom fruit but not in Minitomato fruit after storage at a low temperature. In particular, sHsp 17.4-CII and sHsp23.8-M transcripts strongly accumulated in Micro-Tom fruit and HsfA3 transcript diminished after cold storage. These data suggest that sHsps may be involved in the protection mechanisms against chilling stress and substantiate the hypothesis that sHsps may participate in the mechanism of tomato genotype chilling tolerance. © 2016 Scandinavian Plant Physiology Society.

  8. A socio-cognitive strategy to address farmers' tolerance of high risk work: Disrupting the effects of apprenticeship of observation.

    Science.gov (United States)

    Mazur, Joan M; Westneat, Susan

    2017-02-01

    Why do generations of farmers tolerate the high-risk work of agricultural work and resist safe farm practices? This study presents an analysis inspired by empirical data from studies conducted from 1993 to 2012 on the differing effects of farm safety interventions between participants who live or work on farms and those who don't, when both were learning to be farm safety advocates. Both groups show statistically significant gains in knowledge and behavioral change proxy measures. However, non-farm participants' gains consistently outstripped their live/work farm counterparts. Drawing on socio-cultural perspectives, a grounded theory qualitative analysis focused on identifying useful constructs to understand the farmers' resistance to adopt safety practices. Understanding apprenticeships of observation and its relation to experiential learning over time can expose sources of deeply anchored beliefs and how they operate insidiously to promote familiar, albeit unsafe farming practices. The challenge for intervention-prevention programs becomes how to disrupt what has been learned during these apprenticeships of observation and to address what has been obscured during this powerful socialization process. Implications focus on the design and implementation of farm safety prevention and education programs. First, farm safety advocates and prevention researchers need to attend to demographics and explicitly explore the prior experiences and background of safety program participants. Second, farm youth in particular need to explore, explicitly, their own apprenticeships of observations, preferably through the use of new social media and or digital forms of expression, resulting in a story repair process. Third, careful study of the organization of work and farm experiences and practices need to provide the foundations for intervention programs. Finally, it is crucial that farm safety programs understand apprenticeships of observation are generational and ongoing over time

  9. Comparative transcriptome analysis of Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) reveals novel insights into heat stress tolerance in insects.

    Science.gov (United States)

    Liu, Yuncai; Su, Hang; Li, Rongqiao; Li, Xiaotong; Xu, Yusong; Dai, Xiangping; Zhou, Yanyan; Wang, Huabing

    2017-12-19

    Heat tolerance is a key parameter that affects insect distribution and abundance. Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) is a devastating pest of mulberry in the main mulberry-growing regions and can cause tremendous losses to sericulture by directly feeding on mulberry leaves and transmitting viruses to Bombyx mori. Moreover, G. pyloalis shows a prominent capacity for adaptation to daily and seasonal temperature fluctuations and can survive several hours under high temperature. To date, the molecular mechanism underlying the outstanding adaptability of this pest to high temperature remains unclear. In this study, we performed comparative transcriptome analyses on G. pyloalis exposed to 25 and 40 °C for 4 h. We obtained 34,034 unigenes and identified 1275 and 1222 genes significantly upregulated or downregulated, respectively, by heat stress. Data from the transcriptome analyses indicated that some processes involved in heat tolerance are conserved, such as high expression of heat shock protein (HSP) genes and partial repression of metabolism progress. In addition, vitamin digestion and absorption pathways and detoxification pathways identified here provided new insights for the investigation of the molecular mechanisms of heat stress tolerance. Furthermore, transcriptome analysis indicated that immune and phosphatidylinositol signaling system have a close relationship with heat tolerance. In addition, the expression patterns of ten randomly selected genes, such as HSP and cytochrome P450, were consistent with the transcriptome results obtained through quantitative real-time PCR. Comparisons among transcriptome results revealed the upregulation of HSPs and genes involved in redox homeostasis, detoxication, and immune progress. However, many metabolism progresses, such as glycolysis/gluconeogenesis and fatty acid biosynthesis, were partially repressed. The results reflected that the heat tolerance of G. pyloalis is a fairly complicated process and

  10. Novel mitochondria-targeted heat-soluble proteins identified in the anhydrobiotic Tardigrade improve osmotic tolerance of human cells.

    Directory of Open Access Journals (Sweden)

    Sae Tanaka

    Full Text Available Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called "anhydrobiosis". Late Embryogenesis Abundant (LEA proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble and SAHS (Secretory Abundant Heat Soluble proteins, which are secreted or localized in most intracellular compartments, except the mitochondria. Although mitochondrial integrity is crucial to ensure cellular survival, protective molecules for mitochondria have remained elusive. Here, we identified two novel mitochondrial heat-soluble proteins, RvLEAM and MAHS (Mitochondrial Abundant Heat Soluble, as potent mitochondrial protectants from Ramazzottius varieornatus. RvLEAM is a group3 LEA protein and immunohistochemistry confirmed its mitochondrial localization in tardigrade cells. MAHS-green fluorescent protein fusion protein localized in human mitochondria and was heat-soluble in vitro, though no sequence similarity with other known proteins was found, and one region was conserved among tardigrades. Furthermore, we demonstrated that RvLEAM protein as well as MAHS protein improved the hyperosmotic tolerance of human cells. The findings of the present study revealed that tardigrade mitochondria contain at least two types of heat-soluble proteins that might have protective roles in water-deficient environments.

  11. Heat Tolerances of Salmonella, Cronobacter sakazakii, and Pediococcus acidilactici Inoculated into Galactooligosaccharide.

    Science.gov (United States)

    Bang, Jihyun; Choi, Moonkak; Jeong, Haeseok; Lee, Sangseob; Kim, Yoonbin; Ryu, Jee-Hoon; Kim, Hoikyung

    2017-07-01

    Food-grade galactooligosaccharide (GOS) with low water activity (a w of ca. 0.7) is used as an ingredient in various foods. We evaluated heat tolerances of Salmonella, Cronobacter sakazakii, and Pediococcus acidilactici at temperatures (70 to 85°C) used during the saturation process of GOS by comparing decimal reduction time (D-values) and thermal resistance constants (z-values). To determine the D- and z-values, GOS containing Salmonella (5.1 to 5.8 log CFU/g) or C. sakazakii (5.3 to 5.9 log CFU/g) was heat treated at 70, 77.5, or 85°C for up to 40, 25, or 15 s, respectively, and GOS containing P. acidilactici (6.1 to 6.5 log CFU/g) was heat treated at 70, 77.5, or 85°C for up to 150, 75, or 40 s, respectively. The D-values were calculated using a linear model for heating time versus microbial population for each bacterium. When the D-values for Salmonella, C. sakazakii, and P. acidilactici in GOS were compared, the thermal resistance of all bacteria decreased as the temperature increased. Among the three bacteria, P. acidilactici had higher D-values than did Salmonella and C. sakazakii. The z-values of Salmonella, C. sakazakii, and P. acidilactici were 30.10, 33.18, and 13.04°C, respectively. Overall order of thermal resistance was P. acidilactici > Salmonella ≈ C. sakazakii. These results will be useful for selecting appropriate heat treatment conditions for the decontamination of pathogenic microorganisms during GOS manufacturing.

  12. Using Solar Hot Water to Address Piping Heat Losses in Multifamily Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Springer, David [Alliance for Residential Building Innovation, Davis, CA (United States); Seitzler, Matt [Alliance for Residential Building Innovation, Davis, CA (United States); Backman, Christine [Alliance for Residential Building Innovation, Davis, CA (United States); Weitzel, Elizabeth [Alliance for Residential Building Innovation, Davis, CA (United States)

    2015-10-01

    Solar thermal water heating is most cost effective when applied to multifamily buildings and some states offer incentives or other inducements to install them. However, typical solar water heating designs do not allow the solar generated heat to be applied to recirculation losses, only to reduce the amount of gas or electric energy needed for hot water that is delivered to the fixtures. For good reasons, hot water that is recirculated through the building is returned to the water heater, not to the solar storage tank. The project described in this report investigated the effectiveness of using automatic valves to divert water that is normally returned through the recirculation piping to the gas or electric water heater instead to the solar storage tank. The valves can be controlled so that the flow is only diverted when the returning water is cooler than the water in the solar storage tank.

  13. Phenotyping of wheat cultivars for heat tolerance using chlorophyll a fluorescence

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Andersen, Sven Bode; Ottosen, Carl-Otto

    2012-01-01

    Abstract. In view of the global climate change, heat stress is an increasing constraint for the productivity of wheat (Triticum aestivum L.). Our aim was to identify contrasting cultivars in terms of heat tolerance by mass screening of 1274 wheat cultivars of diverse origin, based...... on a physiological trait, the maximum quantum efficiency of PSII (Fv/Fm). A chlorophyll fluorescence protocol was standardised and used for repeated screening with increased selection pressure with a view to identifying a set of cultivars extreme for the trait. An initial mass screening of 1274 wheat cultivars...... with a milder heat stress of 38Cin 300 mmolm–2 s–1 for 2 h with preheating at 33–35Cfor 19 h in 7–14 mmolm–2 s–1 light showed a genetic determination of 8.52.7%.Aheat treatment of 40Cin 300 mmolm–2 s–1 for 72 h in the second screening with 138 selected cultivars resulted in larger differentiation of cultivars...

  14. Heat Tolerance of the Brown Recluse Spider (Araneae: Sicariidae): Potential for Pest Control.

    Science.gov (United States)

    Cramer, Kenneth L; Zagar, Lindsey M

    2016-02-01

    The brown recluse spider, Loxosceles reclusa Gertsch & Mulaik, is a well-known venomous spider common in the south-central United States where infestations can reach thousands of individuals in a single structure. Bites from this spider pose a risk of dermonecrotic lesions (loxoscelism) or, rarely, more serious systemic effects. The heat tolerance of this spider is understudied but may offer an alternative pest control solution to pesticides or fumigation, both of which have their disadvantages. We subjected brown recluse spiders to increasing temperatures to establish the upper lethal temperature (LT). Using probit analysis to generate probability of mortality at increasing temperatures, we then exposed adult spiders to the observed LT50 to simulate whole-room heat treatment. Laboratory results predict exposure to 48°C for 130 min will achieve 100% mortality of adult spiders. Field tests need to be conducted to determine the efficacy of heat treatment in a variety of real-world situations. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Heat Tolerance in Curraleiro Pe-Duro, Pantaneiro and Nelore Cattle Using Thermographic Images

    Science.gov (United States)

    Cardoso, Caio Cesar; Lima, Flávia Gontijo; Fioravanti, Maria Clorinda Soares; do Egito, Andrea Alves; Silva, Flávia Cristina de Paula e; Tanure, Candice Bergmann; Peripolli, Vanessa; McManus, Concepta

    2016-01-01

    The objective of this study was to compare physiological and thermographic responses to heat stress in three breeds of cattle. Fifteen animals of each of the Nelore, Pantaneiro and Curraleiro Pe-Duro breeds, of approximately two years of age, were evaluated. Heart and respiratory rates, rectal and surface temperature of animals as well as soil temperature were recorded at 8:30 and 15:30 on six days. Variance, correlation, principal factors and canonical analyses were carried out. There were significant differences in the rectal temperature, heart and respiratory rate between breeds (p < 0.001). Nelore and Pantaneiro breeds had the highest rectal temperatures and the lowest respiratory rate (p < 0.001). Breed was also significant for surface temperatures (p < 0.05) showing that this factor significantly affected the response of the animal to heat tolerance in different ways. The Curraleiro Pe-Duro breed had the lowest surface temperatures independent of the period evaluated, with fewer animals that suffered with the climatic conditions, so this may be considered the best adapted when heat challenged under the experimental conditions. Thermography data showed a good correlation with the physiological indexes, and body area, neck and rump were the main points. PMID:26840335

  16. Avian thermoregulation in the heat: resting metabolism, evaporative cooling and heat tolerance in Sonoran Desert doves and quail.

    Science.gov (United States)

    Smith, Eric Krabbe; O'Neill, Jacqueline; Gerson, Alexander R; Wolf, Blair O

    2015-11-01

    Birds in subtropical deserts face significant thermoregulatory challenges because environmental temperatures regularly exceed avian body temperature. To understand the differing susceptibility of desert birds to increasing temperatures, we examined thermoregulatory performance and estimated heat tolerance limits (HTLs) for three Sonoran Desert nesting bird species - Gambel's quail, mourning doves and white-winged doves. Using flow-through respirometry we measured daytime resting metabolism, evaporative water loss and real-time body temperature at air temperatures (T(air)) from 30°C to 66°C. We found marked increases in resting metabolism at the upper critical temperature (T(uc)), which was significantly lower in the quail (T(air)=41.1°C) than in both dove species (T(air)=45.9-46.5°C). Gambel's quail maintained low resting metabolic rates and low rates of evaporative water loss at their T(uc) (0.71 W and 1.20 g H2O h(-1), respectively), but were more sensitive to increasing air temperature, reaching their HTL at T(air) of 52°C. Mourning doves and white-winged doves maintained low resting metabolic rates (0.66 and 0.94 W), but higher rates of evaporative water loss (1.91 and 2.99 g H2O h(-1)) at their T(uc) and reached their HTL at T(air) of 58-60°C. Mass-specific evaporative water loss in white-winged doves (147 g) and mourning doves (104 g) was 45% and 30% greater, respectively, than the rate observed in Gambel's quail (161 g) at Tair of 48°C. Higher rates of evaporation and higher T(uc) made the doves exceptionally heat tolerant, allowing them to maintain body temperatures at least 14°C below air temperatures as high as 60°C (140°F). © 2015. Published by The Company of Biologists Ltd.

  17. Physiological tolerance to uncompensated heat stress in soldiers: Effects of various types of body cooling systems

    Directory of Open Access Journals (Sweden)

    Jovanović Dalibor

    2014-01-01

    directly improve heat tolerance, hydration state, decrease in the risk of heat illness, and extends the duration of soldiers’ exposure to extreme conditions.

  18. ZmHSP16.9, a cytosolic class I small heat shock protein in maize (Zea mays), confers heat tolerance in transgenic tobacco.

    Science.gov (United States)

    Sun, Liping; Liu, Yang; Kong, Xiangpei; Zhang, Dan; Pan, Jiaowen; Zhou, Yan; Wang, Li; Li, Dequan; Yang, Xinghong

    2012-08-01

    Various organisms produce HSPs in response to high temperature and other stresses. The function of heat shock proteins, including small heat shock protein (sHSP), in stress tolerance is not fully explored. To improve our understanding of sHSPs, we isolated ZmHSP16.9 from maize. Sequence alignments and phylogenetic analysis reveal this to be a cytosolic class I sHSP. ZmHSP16.9 expressed in root, leaf and stem tissues under 40 °C treatment, and was up-regulated by heat stress and exogenous H₂O₂. Overexpression of ZmHSP16.9 in transgenic tobacco conferred tolerance to heat and oxidative stresses by increased seed germination rate, root length, and antioxidant enzyme activities compared with WT plants. These results support the positive role of ZmHSP16.9 in response to heat stress in plant. The overexpression of ZmHSP16.9 enhanced tolerance to heat and oxidative stress in transgenic tobacco.

  19. Food crops face rising temperatures: An overview of responses, adaptive mechanisms, and approaches to improve heat tolerance

    Directory of Open Access Journals (Sweden)

    Neeru Kaushal

    2016-12-01

    Full Text Available The rising temperatures are resulting in heat stress for various agricultural crops to limit their growth, metabolism, and leading to significant loss of yield potential worldwide. Heat stress adversely affects normal plant growth and development depending on the sensitivity of each crop species. Each crop species has its own range of temperature maxima and minima at different developmental stages beyond which all these processes get inhibited. The reproductive stage is on the whole more sensitive to heat stress, resulting in impaired fertilization to cause abortion of flowers. During seed filling, heat stress retards seed growth by affecting all the biochemical events to reduce seed size. Unfavorable temperature may significantly affect photosynthesis, respiration, water balance, and membrane stability of leaves. To combat heat stress, plants acquire various defense mechanisms for their survival such as maintaining membrane stability, and scavenging reactive oxygen species by generating antioxidants and stress proteins. Thermo-tolerance can be improved by the accumulation of various compounds of low molecular mass known as thermo-protectants as well as phyto-hormones. Exogenous application of these molecules has benefited plants growing under heat stress. Alternatively, transgenic plants over-expressing the enzymes catalyzing the synthesis of these molecules may be raised to increase their endogenous levels to improve heat tolerance. In recent times, various transgenics have been developed with improved thermo-tolerance having potential benefits for inducing heat tolerance in food crops. Updated information about of the effects of heat stress on various food crops and their responses as well as adaptive mechanisms is reviewed here.

  20. A novel match-line selective charging scheme for high-speed, low-power and noise-tolerant content-addressable memory

    KAUST Repository

    Hasan, Muhammad Mubashwar

    2010-06-01

    Content-addressable memory (CAM) is an essential component for high-speed lookup intensive applications. This paper presents a match-line selective charging technique to increase speed and reduce the energy per bit per search while increasing the noise-tolerance. Simulation in TSMC 0.18 μm technology with 64×72 Ternary CAM shows the match-line energy reduction of 45% compared to the conventional currentsaving scheme with the reduction of minimum cycle time by 68% and the improvement of noise-tolerance by 96%.

  1. Rad9, Rad17, TopBP1 and claspin play essential roles in heat-induced activation of ATR kinase and heat tolerance.

    Directory of Open Access Journals (Sweden)

    Munkhbold Tuul

    Full Text Available Hyperthermia is widely used to treat patients with cancer, especially in combination with other treatments such as radiation therapy. Heat treatment per se activates DNA damage responses mediated by the ATR-Chk1 and ATM-Chk2 pathways but it is not fully understood how these DNA damage responses are activated and affect heat tolerance. By performing a genetic analysis of human HeLa cells and chicken B lymphoma DT40 cells, we found that heat-induced Chk1 Ser345 phosphorylation by ATR was largely dependent on Rad9, Rad17, TopBP1 and Claspin. Activation of the ATR-Chk1 pathway by heat, however, was not associated with FancD2 monoubiquitination or RPA32 phosphorylation, which are known as downstream events of ATR kinase activation when replication forks are stalled. Downregulation of ATR, Rad9, Rad17, TopBP1 or Claspin drastically reduced clonogenic cell viability upon hyperthermia, while gene knockout or inhibition of ATM kinase reduced clonogenic viability only modestly. Suppression of the ATR-Chk1 pathway activation enhanced heat-induced phosphorylation of Chk2 Thr68 and simultaneous inhibition of ATR and ATM kinases rendered severe heat cytotoxicity. These data indicate that essential factors for activation of the ATR-Chk1 pathway at stalled replication forks are also required for heat-induced activation of ATR kinase, which predominantly contributes to heat tolerance in a non-overlapping manner with ATM kinase.

  2. Effects of desiccation and starvation on thermal tolerance and the heat-shock response in forest ants.

    Science.gov (United States)

    Nguyen, Andrew D; DeNovellis, Kerri; Resendez, Skyler; Pustilnik, Jeremy D; Gotelli, Nicholas J; Parker, Joel D; Cahan, Sara Helms

    2017-12-01

    Temperature increases associated with global climate change are likely to be accompanied by additional environmental stressors such as desiccation and food limitation, which may alter how temperature impacts organismal performance. To investigate how interactions between stressors influence thermal tolerance in the common forest ant, Aphaenogaster picea, we compared the thermal resistance of workers to heat shock with and without pre-exposure to desiccation or starvation stress. Knockdown (KD) time at 40.5 °C of desiccated ants was reduced 6% compared to controls, although longer exposure to desiccation did not further reduce thermal tolerance. Starvation, in contrast, had an increasingly severe effect on thermal tolerance: at 21 days, average KD time of starved ants was reduced by 65% compared to controls. To test whether reduction in thermal tolerance results from impairment of the heat-shock response, we measured basal gene expression and transcriptional induction of two heat-shock proteins (hsp70 and hsp40) in treated and control ants. We found no evidence that either stressor impaired the Hsp response: both desiccation and starvation slightly increased basal Hsp expression under severe stress conditions and did not affect the magnitude of induction under heat shock. These results suggest that the co-occurrence of multiple environmental stressors predicted by climate change models may make populations more vulnerable to future warming than is suggested by the results of single-factor heating experiments.

  3. Heat Acclimation-Mediated Cross-Tolerance: Origins in within-Life Epigenetics?

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    Michal Horowitz

    2017-07-01

    Full Text Available The primary outcome of heat acclimation is increased thermotolerance, which stems from enhancement of innate cytoprotective pathways. These pathways produce “ON CALL” molecules that can combat stressors to which the body has never been exposed, via cross-tolerance mechanisms (heat acclimation-mediated cross-tolerance—HACT. The foundation of HACT lies in the sharing of generic stress signaling, combined with tissue/organ- specific protective responses. HACT becomes apparent when acclimatory homeostasis is achieved, lasts for several weeks, and has a memory. HACT differs from other forms of temporal protective mechanisms activated by exposure to lower “doses” of the stressor, which induce adaptation to higher “doses” of the same/different stressor; e.g., preconditioning, hormesis. These terms have been adopted by biochemists, toxicologists, and physiologists to describe the rapid cellular strategies ensuring homeostasis. HACT employs two major protective avenues: constitutive injury attenuation and abrupt post-insult release of help signals enhanced by acclimation. To date, the injury-attenuating features seen in all organs studied include fast-responding, enlarged cytoprotective reserves with HSPs, anti-oxidative, anti-apoptotic molecules, and HIF-1α nuclear and mitochondrial target gene products. Using cardiac ischemia and brain hypoxia models as a guide to the broader framework of phenotypic plasticity, HACT is enabled by a metabolic shift induced by HIF-1α and there are less injuries caused by Ca+2 overload, via channel or complex-protein remodeling, or decreased channel abundance. Epigenetic markers such as post-translational histone modification and altered levels of chromatin modifiers during acclimation and its decline suggest that dynamic epigenetic mechanisms controlling gene expression induce HACT and acclimation memory, to enable the rapid return of the protected phenotype. In this review the link between in vivo

  4. Taking entry heating credit to address planetary protection bio-burden limits

    Science.gov (United States)

    Witte, J.; Clark, B.; Linch, S.; Johnson, M.; Bomba, K.; Oakman, K.; Tice, N.; Kast, W.; Willcockson, W.

    In 2005 NASA will launch a large orbiting science observatory, the Mars Reconnaissance Orbiter (MRO), for what should be a 5.4-year mission. High resolution imaging of the surface is a principle goal of the mission. One consequence of this goal however is the need for a low science orbit. Unfortunately this orbit fails the required 20-year orbit life requirements set in NASA Policy Guideline. So rather than sacrifice the science goals of the mission by raising the science orbit, the MRO Project chose to be the first orbiter to pursue the bio-burden reduction approach. Because the orbiter is so large, cleaning only is insufficient to achieve the bio-burden threshold requirement in NASA Policy. This presentation outlines one of the processes developed to reduce bio-burden by taking credit for hardware that will either never reach the surface or achieves high temperature during entry due to ablation and aero-heating. Lockheed Martin engineers developed a process to perform what is called breakup and burn-up analysis. This process considers the assumptions that go into modeling and into decision methods that result on structural degradation branching points. Structural degradation rate is driven by thermal properties of the hardware. These branching points produce multiple trajectory bodies of their own. Assumptions of body shape, mass and velocity drive the rate aero-heating in the entry trajectory. As entry velocity decays so does the available entry heating. In the end, an inventory of all the SC hardware is done in terms of Exempt (burned-up or sufficiently heated) and Non-exempt (survived to surface) components. © Lockheed Martin Corporation A companion paper by the Jet Propulsion Laboratory discusses how this data is integrated into the overall bio-burden assessment activity and the derivation of the Implementation Plan.

  5. Heritability and Genetic Advance among Chili Pepper Genotypes for Heat Tolerance and Morphophysiological Characteristics

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    Magaji G. Usman

    2014-01-01

    Full Text Available High temperature tolerance is an important component of adaptation to arid and semiarid cropping environment in chili pepper. Two experiments were carried out to study the genetic variability among chili pepper for heat tolerance and morphophysiological traits and to estimate heritability and genetic advance expected from selection. There was a highly significant variation among the genotypes in response to high temperature (CMT, photosynthesis rate, plant height, disease incidence, fruit length, fruit weight, number of fruits, and yield per plant. At 5% selection intensity, high genetic advance as percent of the mean (>20% was observed for CMT, photosynthesis rate, fruit length, fruit weight, number of fruits, and yield per plant. Similarly, high heritability (>60% was also observed indicating the substantial effect of additive gene more than the environmental effect. Yield per plant showed strong to moderately positive correlations (r=0.23–0.56 at phenotypic level while at genotypic level correlation coefficient ranged from 0.16 to 0.72 for CMT, plant height, fruit length, and number of fruits. Cluster analysis revealed eight groups and Group VIII recorded the highest CMT and yield. Group IV recorded 13 genotypes while Groups II, VII, and VIII recorded one each. The results showed that the availability of genetic variance could be useful for exploitation through selection for further breeding purposes.

  6. Heterologous expression of three Camellia sinensis small heat shock protein genes confers temperature stress tolerance in yeast and Arabidopsis thaliana.

    Science.gov (United States)

    Wang, Mingle; Zou, Zhongwei; Li, Qinghui; Xin, Huahong; Zhu, Xujun; Chen, Xuan; Li, Xinghui

    2017-07-01

    CsHSP17.7, CsHSP18.1, and CsHSP21.8 expressions are induced by heat and cold stresses, and CsHSP overexpression confers tolerance to heat and cold stresses in transgenic Pichia pastoris and Arabidopsis thaliana. Small heat shock proteins (sHSPs) are crucial for protecting plants against biotic and abiotic stresses, especially heat stress. However, knowledge concerning the functions of Camellia sinensis sHSP in heat and cold stresses remains poorly understood. In this study, three C. sinensis sHSP genes (i.e., CsHSP17.7, CsHSP18.1, and CsHSP21.8) were isolated and characterized using suppression subtractive hybridization (SSH) technology. The CsHSPs expression levels in C. sinensis leaves were significantly up-regulated by heat and cold stresses. Phylogenetic analyses revealed that CsHSP17.7, CsHSP18.1, and CsHSP21.8 belong to sHSP Classes I, II, and IV, respectively. Heterologous expression of the three CsHSP genes in Pichia pastoris cells enhanced heat and cold stress tolerance. When exposed to heat and cold treatments, transgenic Arabidopsis thaliana plants overexpressing CsHSP17.7, CsHSP18.1, and CsHSP21.8 had lower malondialdehyde contents, ion leakage, higher proline contents, and transcript levels of stress-related genes (e.g., AtPOD, AtAPX1, AtP5CS2, and AtProT1) compared with the control line. In addition, improved seed germination vigor was also observed in the CsHSP-overexpressing seeds under heat stress. Taken together, our results suggest that the three identified CsHSP genes play key roles in heat and cold tolerance.

  7. LeCDJ1, a chloroplast DnaJ protein, facilitates heat tolerance in transgenic tomatoes.

    Science.gov (United States)

    Kong, Fanying; Deng, Yongsheng; Wang, Guodong; Wang, Jieru; Liang, Xiaoqing; Meng, Qingwei

    2014-01-01

    The roles of a tomato (Lycopersicon esculentum) chloroplast-targeted DnaJ protein (LeCDJ1) were investigated using wild-type (WT) and sense transgenic tomatoes. The LeCDJ1 expression was upregulated by 38 °C, 42 °C, 45 °C, NaCl, PEG, methyl viologen (MV) and hydrogen peroxide (H2O2), but not by 30 °C and 35 °C. Meanwhile, LeCDJ1 was involved in the response of plants to abscisic acid (ABA). Under heat stress, the sense plants showed better growth, higher chlorophyll content, lower malondialdehyde (MDA) accumulation and relative electrical conductivity (REC), and also less PSII photoinhibition than WT. Interestingly, the sense plants treated with streptomycin (SM), an inhibitor of organellar translation, still showed higher maximum photochemistry efficiency of PSII (Fv/Fm) and D1 protein levels than the SM-untreated WT, suggesting that the protective effect of LeCDJ1 on PSII was, at least partially, independent of D1 protein synthesis. Furthermore, the relatively lower superoxide radical (O2(•-)) and H2O2 levels in the sense plants were considered to be due to the higher ascorbate peroxidase (APX) and superoxide dismutase (SOD) activity, which seemed unlikely dependent on their transcription level. These results indicated that LeCDJ1 overexpression facilitated heat tolerance in transgenic tomatoes. © 2013 Institute of Botany, Chinese Academy of Sciences.

  8. Quantitative trait loci mapping of heat tolerance in a doubled haploid population of broccoli using genotyping-by-sequencing

    Science.gov (United States)

    Broccoli is a cool weather vegetable crop with a vernalization requirement to initiate and maintain floral development. Breeding for heat tolerance in broccoli has the potential to both expand viable production areas and extend the growing season. A doubled haploid (DH) population of broccoli (Bras...

  9. Heat or cold priming-induced cross-tolerance to abiotic stresses in plants: key regulators and possible mechanisms.

    Science.gov (United States)

    Hossain, Mohammad Anwar; Li, Zhong-Guang; Hoque, Tahsina Sharmin; Burritt, David J; Fujita, Masayuki; Munné-Bosch, Sergi

    2018-01-01

    Plants growing under field conditions are constantly exposed, either simultaneously or sequentially, to more than one abiotic stress factor. Plants have evolved sophisticated sensory systems to perceive a number of stress signals that allow them to activate the most adequate response to grow and survive in a given environment. Recently, cross-stress tolerance (i.e. tolerance to a second, strong stress after a different type of mild primary stress) has gained attention as a potential means of producing stress-resistant crops to aid with global food security. Heat or cold priming-induced cross-tolerance is very common in plants and often results from the synergistic co-activation of multiple stress signalling pathways, which involve reactive nitrogen species (RNS), reactive oxygen species (ROS), reactive carbonyl species (RCS), plant hormones and transcription factors. Recent studies have shown that the signalling functions of ROS, RNS and RCS, most particularly hydrogen peroxide, nitric oxide (NO) and methylglyoxal (MG), provide resistance to abiotic stresses and underpin cross-stress tolerance in plants by modulating the expression of genes as well as the post-translational modification of proteins. The current review highlights the key regulators and mechanisms underlying heat or cold priming-induced cross-stress tolerance in plants, with a focus on ROS, MG and NO signalling, as well as on the role of antioxidant and glyoxalase systems, osmolytes, heat-shock proteins (HSPs) and hormones. Our aim is also to provide a comprehensive idea on the topic for researchers using heat or cold priming-induced cross-tolerance as a mechanism to improve crop yields under multiple abiotic stresses.

  10. Tick resistance and heat tolerance characteristics in cattle. II. Rectal temperature and respiratory frequency

    Directory of Open Access Journals (Sweden)

    Cecília José Veríssimo

    2012-12-01

    Full Text Available The heat and Rhipicephalus microplus tick infestation are limiting factors to the livestock production in the tropics. Therefore, in a tropical sustainable livestock, cattle should be tick resistant and heat tolerant. The relationship between the Rhipicephalus (Boophilus microplus tick infestation and heat characteristics like rectal temperature and respiratory frequency was studied in 6 Nellore and 4 Holstein, seven-month-old steers. They were submitted to an artificial infestation (a.i. with 10,000 larvae (Holstein and 20,000 larvae (Nellore of Rhipicephalus (Boophilus microplus tick in 16/Apr/2011. Females ticks bigger than 4.0 mm were counted in the left side from day 19 to 27 after the artificial infestation. The infestation rate was calculated by summing and multiplying by two the number of ticks counted, assuming that females are half of infesting larvae (5,000 for Holstein and 10,000 for Nellore. In days 20, 23 and 24 after the infestation, the 10 bigger females ticks found in whole animal were weighed and put in a chamber (27 oC and 80% RH, weighing the egg mass of each female fourteen days after. The rectal temperature (RT, measured by a digital thermometer in the animal’s rectum and respiratory frequency (RF, respiratory movements per minute were measured on days 14/Apr (2 days before the a.i. and on day 05/May (19 days after the a.i.. The RT and RF were measured in the morning and in the afternoon, after they had been exposed to noon sun. The experimental design was a non-probability sample restricted to the 10 available animals. Analyses of variance for the random variables RT and RF to evaluate the effects of period of day, date and breed were performed using the SPSS 12.0. The RF was greater in the afternoon (64.82 ± 2.44 mov/min versus 38.42 ± 2.44 mov/min in the morning, P<0.001 and did not varied between dates; Nellore cattle had lower RF (41.50 ± 2.20 mov/min than Holstein (61.75 ± 2.70 mov/min, P<0.001. About RT, breed

  11. Cold acclimation alters DNA methylation patterns and confers tolerance to heat and increases growth rate in Brassica rapa.

    Science.gov (United States)

    Liu, Tongkun; Li, Ying; Duan, Weike; Huang, Feiyi; Hou, Xilin

    2017-02-01

    Epigenetic modifications are implicated in plant adaptations to abiotic stresses. Exposure of plants to one stress can induce resistance to other stresses, a process termed cross-adaptation, which is not well understood. In this study, we aimed to unravel the epigenetic basis of elevated heat-tolerance in cold-acclimated Brassica rapa by conducting a genome-wide DNA methylation analysis of leaves from control (CK) and cold-acclimated (CA) plants. We found that both methylation and demethylation occurred during cold acclimation. Two significantly altered pathways, malate dehydrogenase activity and carbon fixation, and 1562 differentially methylated genes, including BramMDH1, BraKAT2, BraSHM4, and Bra4CL2, were identified in CA plants. Genetic validation and treatment of B. rapa with 5-aza-2-deoxycytidine (Aza) suggested that promoter demethylation of four candidate genes increased their transcriptional activities. Physiological analysis suggested that elevated heat-tolerance and high growth rate were closely related to increases in organic acids and photosynthesis, respectively. Functional analyses demonstrated that the candidate gene BramMDH1 (mMDH: mitochondrial malate dehydrogenase) directly enhances organic acids and photosynthesis to increase heat-tolerance and growth rate in Arabidopsis. However, Aza-treated B. rapa, which also has elevated BramMDH1 levels, did not exhibit enhanced heat-tolerance. We therefore suggest that DNA demethylation alone is not sufficient to increase heat-tolerance. This study demonstrates that altered DNA methylation contributes to cross-adaptation. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  12. Heat-tolerant versus heat-sensitive Bos taurus cattle: influence of air temperature and breed on the acute phase response to a provocative immune challenge.

    Science.gov (United States)

    Carroll, J A; Burdick Sanchez, N C; Chaffin, R; Chase, C C; Coleman, S W; Spiers, D E

    2013-10-01

    The difference in the acute phase response of a heat-tolerant and a heat-sensitive Bos taurus breed to a lipopolysaccharide (LPS) challenge when housed at different air temperatures (Ta) was studied. Angus (ANG; heat-sensitive; n = 11; 306 ± 26 kg BW) and Romosinuano (RO; heat-tolerant; n = 10; 313 ± 32 kg BW) heifers were transported from the USDA Agricultural Research Service SubTropical Agricultural Research Station in Florida to the Brody Environmental Chambers at the University of Missouri, Columbia. Heifers were housed in stanchions in 4 temperature-controlled environmental chambers. Initially, Ta in the 4 chambers was cycling at thermoneutrality (TN; 18.5°C-23.5°C) for a 1-wk adjustment period, followed by an increase in 2 of the 4 chambers to cycling heat stress (HS; 24°C-38°C) for 2 wk. On day 19, heifers were fitted with jugular catheters and rectal temperature (RT) recording devices. On day 20, heifers were challenged with LPS (0.5 μg/kg BW; 0 h), sickness behavior scores (SBSs) were recorded, and blood samples were collected at 0.5-h intervals from -2 to 8 h and again at 24 h relative to LPS challenge at 0 h. Serum was isolated and stored at -80°C until analyzed for cortisol and cytokine concentrations. A breed by Ta interaction (P heat-tolerant RO and heat-sensitive ANG heifers under different Ta which may aid in elucidating differences in productivity, disease resistance, and longevity among cattle breeds. Published by Elsevier Inc.

  13. Tick resistance and heat tolerance characteristics in cattle. III. Sweating rate

    Directory of Open Access Journals (Sweden)

    Cecília José Veríssimo

    2012-12-01

    Full Text Available Cattle in a sustainable tropical livestock should be heat tolerant and resistant to ticks. The relationship between Rhipicephalus (Boophilus microplus infestation and sweating rate, an important heat tolerance characteristic, was studied in six Nellore and four Holstein steers of seven-month-old. They were artificial infested (a.i. with 10,000 (Holstein and 20,000 (Nellore larvae in 16/Apr/2011. In days 20, 23 and 24 after the infestation, the 10 bigger females ticks found in whole animal were weighed and put in a chamber (27 oC and 80% RH, weighing the egg mass of each female tick fourteen days after. The sweating rate (SRskin, measured by Scheleger and Turner, 1963, method, in a shaved area of shoulder skin was evaluated in 14/Apr (2 days before the a.i. and in 05/May (19 days after a.i.. In 14/Apr the Scheleger and Turner, 1963, method was done on the coat not shaved (SRcoat. The sweating rate was measured in the afternoon (from 2 P.M., after 30 minutes of direct sunlight, on April. On May, the animals remained 60 minutes in direct sunlight because this day was colder. The experimental design was a non-probability sample restricted to the 10 available animals. Data from the steers’ sweating rate were analyzed using the General linear models of the SPSS® statistical package (version 12.0 using SRskin as dependent variable and breed and sampling date as independent variables. For SRcoat breed was the independent variable. Nellore, a tropical cattle breed, had higher SRskin (1,000.82 ± 64.59 g m-2 h-1, P< 0.001 than Holstein (620.45 ± 79.10 g m-2 h-1. SRskin was higher on May (1,187.33 ± 71.49 g m-2 h-1, P< 0.001 than on April (433.93 ± 71.49 g m-2 h-1. The correlation between the two different measurements of SR was positive and significant (r= 0,545, P<0,01, Pearson correlation. But in SRcoat the breed effect disappeared because the Holstein SRcoat increased (Holstein: 884.95 ± 472.12 g m-2 h-1 and Nellore: 1,060.72 ± 318.21 g m-2 h-1

  14. Impact of desiccation and heat exposure stress on Salmonella tolerance to acidic conditions.

    Science.gov (United States)

    Richardson, Kurt E; Cox, Nelson A; Cosby, Douglas E; Berrang, Mark E

    2018-02-01

    In a recent study, the pH of commonly used Salmonella pre-enrichment media became acidic (pH 4.0 to 5.0) when feed or feed ingredients were incubated for 24 h. Acidic conditions have been reported to injure or kill Salmonella. In this study, cultures of four known feed isolates (S. montevideo, S. senftenberg, S. tennessee, and S. schwarzengrund) and four important processing plant isolates (S. typhimurium, S. enteritidis, S. infantis, and S. heidelberg) were grown on meat and bone meal and later subjected to desiccation and heat exposure to stress the microorganism. The impact of stress on the isolates ability to survive in acidic conditions ranging from pH 4.0 to 7.0 was compared to the non-stressed isolate. Cell injury was determined on xylose lysine tergitol 4 (XLT4) and cell death determined on nutrient agar (NA). When measured by cell death in non-stressed Salmonella, S. typhimurium was the most acid tolerant and S. heidelberg was the most acid sensitive whereas in stressed Salmonella, S. senftenberg was the most acid tolerant and S. tennessee was the most acid sensitive. The pH required to cause cell injury varied among isolates. With some isolates, the pH required for 50% cell death and 50% cell injury was similar. In other isolates, cell injury occurred at a more neutral pH. These findings suggest that the pH of pre-enrichment media may influence the recovery and bias the serotype of Salmonella recovered from feed during pre-enrichment.

  15. Role of trehalose in heat and desiccation tolerance in the soil bacterium Rhizobium etli

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    Reina-Bueno Mercedes

    2012-09-01

    Full Text Available Abstract Background The compatible solute trehalose is involved in the osmostress response of Rhizobium etli, the microsymbiont of Phaseolus vulgaris. In this work, we reconstructed trehalose metabolism in R. etli, and investigated its role in cellular adaptation and survival to heat and desiccation stress under free living conditions. Results Besides trehalose as major compatible solute, R. etli CE3 also accumulated glutamate and, if present in the medium, mannitol. Putative genes for trehalose synthesis (otsAB/treS/treZY, uptake (aglEFGK/thuEFGK and degradation (thuAB/treC were scattered among the chromosome and plasmids p42a, p42c, p42e, and p42f, and in some instances found redundant. Two copies of the otsA gene, encoding trehalose-6-P-synthase, were located in the chromosome (otsAch and plasmid p42a (otsAa, and the latter seemed to be acquired by horizontal transfer. High temperature alone did not influence growth of R. etli, but a combination of high temperature and osmotic stress was more deleterious for growth than osmotic stress alone. Although high temperature induced some trehalose synthesis by R. etli, trehalose biosynthesis was mainly triggered by osmotic stress. However, an otsAch mutant, unable to synthesize trehalose in minimal medium, showed impaired growth at high temperature, suggesting that trehalose plays a role in thermoprotection of R. etli. Desiccation tolerance by R. etli wild type cells was dependent of high trehalose production by osmotic pre-conditioned cells. Cells of the mutant strain otsAch showed ca. 3-fold lower survival levels than the wild type strain after drying, and a null viability after 4 days storage. Conclusions Our findings suggest a beneficial effect of osmotic stress in R. etli tolerance to desiccation, and an important role of trehalose on the response of R. etli to high temperature and desiccation stress.

  16. Transgenic tobacco plants overexpressing a grass PpEXP1 gene exhibit enhanced tolerance to heat stress.

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    Qian Xu

    Full Text Available Heat stress is a detrimental abiotic stress limiting the growth of many plant species and is associated with various cellular and physiological damages. Expansins are a family of proteins which are known to play roles in regulating cell wall elongation and expansion, as well as other growth and developmental processes. The in vitro roles of expansins regulating plant heat tolerance are not well understood. The objectives of this study were to isolate and clone an expansin gene in a perennial grass species (Poa pratensis and to determine whether over-expression of expansin may improve plant heat tolerance. Tobacco (Nicotiana tabacum was used as the model plant for gene transformation and an expansin gene PpEXP1 from Poa pratensis was cloned. Sequence analysis showed PpEXP1 belonged to α-expansins and was closely related to two expansin genes in other perennial grass species (Festuca pratensis and Agrostis stolonifera as well as Triticum aestivum, Oryza sativa, and Brachypodium distachyon. Transgenic tobacco plants over-expressing PpEXP1 were generated through Agrobacterium-mediated transformation. Under heat stress (42°C in growth chambers, transgenic tobacco plants over-expressing the PpEXP1 gene exhibited a less structural damage to cells, lower electrolyte leakage, lower levels of membrane lipid peroxidation, and lower content of hydrogen peroxide, as well as higher chlorophyll content, net photosynthetic rate, relative water content, activity of antioxidant enzyme, and seed germination rates, compared to the wild-type plants. These results demonstrated the positive roles of PpEXP1 in enhancing plant tolerance to heat stress and the possibility of using expansins for genetic modification of cool-season perennial grasses in the development of heat-tolerant germplasm and cultivars.

  17. In vitro induction of variation through radiation for late blight resistance and heat tolerance in potato

    International Nuclear Information System (INIS)

    Minocha, J.L.; Das, A.; Gopal, J.; Gosal, S.S.

    1997-01-01

    In vitro plants were obtained from nodal sections of sprouts of cvs. 'Kufri Jyoti' and 'Kufri Chandramukhi' of potato cultured on MS medium with 3% sucrose. Callus from leaves of in vitro cultured plantlets was induced on modified Linsmaier and Skoog medium supplemented with 5 mg/1 NAA. The obtained shoots and calli were irradiated with 20 and 40 Gy gamma rays. Irradiatied shoots were transferred to MS medium with 8% sucrose for multiplication, and then to MS medium with 8% sucrose and 10 mg/1 BAP to induce microtuber formation, which gave on average 1.3 microtubers per plant. The microtubers were planted in pots and variation was observed in plant morphology and tuber characters. To study variation for late blight resistance, irradiated calli were kept on Gamborg B-5 medium with culture filtrate of Phytophthora infestans. To induce variation for heat tolerance, in vitro shoots from irradiated material were mass-propagated and allowed to produce microtubers at high temperature. (author). 3 refs, 3 tabs

  18. Evaluation of Air Pollution Tolerance Index of Plants and Ornamental Shrubs in Enugu City: Implications for Urban Heat Island Effect

    Directory of Open Access Journals (Sweden)

    2016-11-01

    Full Text Available The study compared the air pollution tolerance indices (APTI of five plant species and five ornamental shrubs in Enugu Urban Center. Laboratory analysis was performed on the four physiological and biological parameters including leaf relative water content (RWC, ascorbic acid (AA content, total leaf chlorophyll (TCH and leaf extract pH. These parameters were used to develop an air pollution tolerance index. Factor analysis and descriptive statistics were utilized in the analysis to examine the interactions between these parameters. Vegetation monitoring in terms of its APTI acts as a \\'Bioindicator\\' of air pollution. The study also showed the possibility of utilizing APTI as a tool for selecting plants or ornamental shrubs for urban heat Island mitigation in Enugu City. The result of APTI showed order of tolerance for plants as Anacarduim occidentale (23.20, Pinus spp (22.35, Catalpa burgei (22.57, Magifera indica (23.37, and Psidum guajava (24.15.The result of APTI showed increasing order of sensitivity for ornamental shrubs from ixora red (14.32, yellow ficus(12.63, masquerade pine(12.26, Tuja pine(11.000,to Yellow bush(10.60. The APTI of all the plants examined were higher than those of ornamental shrubs. Thus suggesting that plants in general were more tolerant to air pollution than ornamental shrubs. The ornamental shrubs with lower APTI values (sensitive were recommended as bioindicator of poor urban air quality while plants with high APTI values (tolerant are planted around areas anticipated to have high air pollution load. The result of this current study is therefore handy for future planning and as well provides tolerant species for streetscape and urban heat island mitigation.

  19. A Reliability Comparison of Classical and Stochastic Thickness Margin Approaches to Address Material Property Uncertainties for the Orion Heat Shield

    Science.gov (United States)

    Sepka, Steve; Vander Kam, Jeremy; McGuire, Kathy

    2018-01-01

    The Orion Thermal Protection System (TPS) margin process uses a root-sum-square approach with branches addressing trajectory, aerothermodynamics, and material response uncertainties in ablator thickness design. The material response branch applies a bond line temperature reduction between the Avcoat ablator and EA9394 adhesive by 60 C (108 F) from its peak allowed value of 260 C (500 F). This process is known as the Bond Line Temperature Material Margin (BTMM) and is intended to cover material property and performance uncertainties. The value of 60 C (108 F) is a constant, applied at any spacecraft body location and for any trajectory. By varying only material properties in a random (monte carlo) manner, the perl-based script mcCHAR is used to investigate the confidence interval provided by the BTMM. In particular, this study will look at various locations on the Orion heat shield forebody for a guided and an abort (ballistic) trajectory.

  20. Tolerating Zero Tolerance?

    Science.gov (United States)

    Moore, Brian N.

    2010-01-01

    The concept of zero tolerance dates back to the mid-1990s when New Jersey was creating laws to address nuisance crimes in communities. The main goal of these neighborhood crime policies was to have zero tolerance for petty crime such as graffiti or littering so as to keep more serious crimes from occurring. Next came the war on drugs. In federal…

  1. Neural progenitor cell proliferation in the hypothalamus is involved in acquired heat tolerance in long-term heat-acclimated rats.

    Science.gov (United States)

    Matsuzaki, Kentaro; Katakura, Masanori; Sugimoto, Naotoshi; Hara, Toshiko; Hashimoto, Michio; Shido, Osamu

    2017-01-01

    Constant exposure to moderate heat facilitates progenitor cell proliferation and neuronal differentiation in the hypothalamus of heat-acclimated (HA) rats. In this study, we investigated neural phenotype and responsiveness to heat in HA rats' hypothalamic newborn cells. Additionally, the effect of hypothalamic neurogenesis on heat acclimation in rats was evaluated. Male Wistar rats (5 weeks old) were housed at an ambient temperature (Ta) of 32°C for 6 days (STHA) or 40 days (LTHA), while control (CN) rats were kept at a Ta of 24°C for 6 days (STCN) or 40 days (LTCN). Bromodeoxyuridine (BrdU) was intraperitoneally injected daily for five consecutive days (50 mg/kg/day) after commencing heat exposure. The number of hypothalamic BrdU-immunopositive (BrdU+) cells in STHA and LTHA rats was determined immunohistochemically in brain samples and found to be significantly greater than those in respective CN groups. In LTHA rats, approximately 32.6% of BrdU+ cells in the preoptic area (POA) of the anterior hypothalamus were stained by GAD67, a GABAergic neuron marker, and 15.2% of BrdU+ cells were stained by the glutamate transporter, a glutamatergic neuron marker. In addition, 63.2% of BrdU+ cells in the POA were immunolabeled with c-Fos. Intracerebral administration of the mitosis inhibitor, cytosine arabinoside (AraC), interfered with the proliferation of neural progenitor cells and acquired heat tolerance in LTHA rats, whereas the selected ambient temperature was not changed. These results demonstrate that heat exposure generates heat responsive neurons in the POA, suggesting a pivotal role in autonomic thermoregulation in long-term heat-acclimated rats.

  2. Heat shock protein gene family of the Porphyra seriata and enhancement of heat stress tolerance by PsHSP70 in Chlamydomonas.

    Science.gov (United States)

    Park, Hong-Sil; Jeong, Won-Joong; Kim, EuiCheol; Jung, Youngja; Lim, Jong Min; Hwang, Mi Sook; Park, Eun-Jeong; Ha, Dong-Soo; Choi, Dong-Woog

    2012-06-01

    Heat shock proteins and molecular chaperones are key components contributing to survival in the abiotic stress response. Porphyra seriata grows on intertidal rocks exposed to dynamic environmental changes associated with the turning tides, including desiccation and heat stress. Analysis of the ESTs of P. seriata allows us to identify the nine HSP cDNAs, which are predicted to be PsHSP90, three PsHSP70, PsHSP40 and PsHSP20, and three 5'-truncated HSP cDNAs. RT-PCR results show that most of the PsHSP transcripts were detected under normal cell growth conditions as well as heat stress, with the exception of two cDNAs. In particular, PsHSP70b and PsHSP20 transcripts were upregulated by heat stress. When the putative mitochondrial PsHSP70b was introduced and overexpressed in Chlamydomonas, transformed Chlamydomonas evidenced higher rates of survival and growth than those of the wild type under heat stress conditions. Constitutive overexpression of the PsHSP70b gene increases the transcription of the HSF1 as well as the CrHSP20 and CrHSP70 gene. These results indicate that PsHSP70b is involved in tolerance to heat stress and the effects on transcription of the CrHSP20 and CrHSP70 genes.

  3. Tick resistance and heat tolerance characteristics in cattle. I. Hair length and coat thickness

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    Cecília José Veríssimo

    2012-12-01

    Full Text Available To be heat adapted and Rhipicephalus (Boophilus microplus tick resistant are important characteristics for cattle in the Brazilian sustainable livestock, because this ectoparasite causes serious harm to the health of susceptible animals and, in the tropics, not heat adapted cattle have poor performance. Besides, the control of this tick is increasingly difficult due to drug resistance. Relationship between tick infestation and heat tolerance traits, as the hair length and coat thickness, are important because animals with long hair are easily identifiable, helping in the disposal of the least adapted cattle. In order to infer the relationship between tick infestation and fur characteristics, 6 Nellore and 4 Black and White Holstein steers, with about seven months old, underwent an artificial infestation (with 10,000 larvae on the Holstein, and 20,000 larvae on the Nellore in 16/April/2011. In days 20, 23 and 24 post-infestation, the bigger 10 females ticks found throughout the body were weighed and their egg mass weighed 14 days later. Hair length, HL (collected with pliers specially adapted for this purpose, and measured the 10 longest hair and the coat thickness, CT (measured with a metal ruler inserted perpendicular to the skin were evaluated in the middle of the shoulder on 11/April (5 days before artificial tick infestation and on 12/May (26 days after artificial tick infestation. The experimental design was a non-probability sample restricted to the 10 available animals. Data of HL and CT were analyzed using General linear models of the SPSS® statistical package (version 12.0 using breed and sampling day as independent variables. There were significant differences between the measurements obtained on April and May, respectively: HL Nellore: 9.53 ± 1.80 mm and 14.55 ± 1.77 mm; HL Holstein: 23.40 ± 9.29 and 34.05 ± 5.50 mm, P <0.001; CT Nellore: 2.83 ± 0.41 mm and 3.16 ± 0.98 mm; CT Holstein: 5.00 ± 1.63 mm and 13.75 ± 4.78 mm, P <0

  4. Overexpression of a heat shock protein (ThHSP18.3) from Tamarix hispida confers stress tolerance to yeast.

    Science.gov (United States)

    Gao, Caiqiu; Jiang, Bo; Wang, Yucheng; Liu, Guifeng; Yang, Chuanping

    2012-04-01

    It is well known that plant heat shock proteins (HSPs) play important roles both in response to adverse environmental conditions and in various developmental processes. However, among plant HSPs, the functions of tree plant HSPs are poorly characterized. To improve our understanding of tree HSPs, we cloned and characterized an HSP gene (ThHSP18.3) from Tamarix hispida. Sequence alignment reveals that ThHSP18.3 belongs to the class I small heat shock protein family. A transient expression assay showed that ThHSP18.3 protein was targeted to the cell nucleus. Treatment of Tamarix hispida with cold and heat shock highly induced ThHSP18.3 expression in all studied leaves, roots and stems, whereas, treatment of T. hispida with NaCl, NaHCO(3), and PEG induced ThHSP18.3 expression in leaves and decreased its expression in roots and stems. Further, to study the role of ThHSP18.3 in stress tolerance under different stress conditions, we cloned ThHSP18.3 into the pYES2 vector, transformed and expressed the vector in yeast Saccharomyces cerevisiae. Yeast cells transformed with an empty pYES2 vector were employed as a control. Compared to the control, yeast cells expressing ThHSP18.3 showed greater tolerance to salt, drought, heavy metals, and both low and high temperatures, indicating that ThHSP18.3 confers tolerance to these stress conditions. These results suggested that ThHSP18.3 is involved in tolerance to a variety of stress conditions in T. hispida.

  5. Involvement of ascorbate peroxidase and heat shock proteins on citrus tolerance to combined conditions of drought and high temperatures.

    Science.gov (United States)

    Balfagón, Damián; Zandalinas, Sara I; Baliño, Pablo; Muriach, María; Gómez-Cadenas, Aurelio

    2018-03-27

    Usually several environmental stresses occur in nature simultaneously causing a unique plant response. However, most of the studies until now have focused in individually-applied abiotic stress conditions. Carrizo citrange (Poncirus trifoliata L. Raf. X Citrus sinensis L. Osb.) and Cleopatra mandarin (Citrus reshni Hort. ex Tan.) are two citrus rootstocks with contrasting tolerance to drought and heat stress and have been used in this work as a model for the study of plant tolerance to the combination of drought and high temperatures. According to our results, leaf integrity and photosynthetic machinery are less affected in Carrizo than in Cleopatra under combined conditions of drought and heat stress. The pattern of accumulation of three proteins (APX, HSP101 and HSP17.6) involved in abiotic stress tolerance shows that they do not accumulate under water stress conditions individually applied. However, contents of APX and HSP101 are higher in Carrizo than in Cleopatra under stress combination whereas HSP17.6 has a similar behavior in both types of plants. This, together with a better stomatal control and a higher APX activity of Carrizo, contributes to the higher tolerance of Carrizo plants to the combination of stresses and point to it as a better rootstock than Cleopatra (traditionally used in areas with scare water supplies) under the predictable future climatic conditions with frequent periods of drought combined with high temperatures. This work also provides the basis for testing the tolerance of different citrus varieties grafted on these rootstocks and growing under different field conditions. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  6. Drought priming at vegetative growth stages improves tolerance to drought and heat stresses occurring during grain filling in spring wheat

    DEFF Research Database (Denmark)

    Wang, Xiao; Vignjevic, Marija; Liu, Fulai

    2015-01-01

    Plants of spring wheat (Triticum aestivum L. cv. Vinjett) were exposed to moderate water deficit at the vegetative growth stages six-leaf and/or stem elongation to investigate drought priming effects on tolerance to drought and heat stress events occurring during the grain filling stage....... Comparedwith the non-primed plants, drought priming could alleviate photo-inhibition in flag leaves caused by drought and heat stress episodes during grain filling. In the primed plants, drought stress inhibited photosynthesis mainly through decrease of maximum photosynthetic electron transport rate, while...... decrease of the carboxylation efficiency limited photosynthesis under heat stress. The higher saturated net photosynthetic rate of flag leaves coincidedwith the lowered nonphotochemical quenching rates in the twice-primed plants under drought stress and in the primed plants during stem elongation under...

  7. Overexpression of WsSGTL1 gene of Withania somnifera enhances salt tolerance, heat tolerance and cold acclimation ability in transgenic Arabidopsis plants.

    Directory of Open Access Journals (Sweden)

    Manoj K Mishra

    Full Text Available BACKGROUND: Sterol glycosyltrnasferases (SGT are enzymes that glycosylate sterols which play important role in plant adaptation to stress and are medicinally important in plants like Withania somnifera. The present study aims to find the role of WsSGTL1 which is a sterol glycosyltransferase from W. somnifera, in plant's adaptation to abiotic stress. METHODOLOGY: The WsSGTL1 gene was transformed in Arabidopsis thaliana through Agrobacterium mediated transformation, using the binary vector pBI121, by floral dip method. The phenotypic and physiological parameters like germination, root length, shoot weight, relative electrolyte conductivity, MDA content, SOD levels, relative electrolyte leakage and chlorophyll measurements were compared between transgenic and wild type Arabidopsis plants under different abiotic stresses--salt, heat and cold. Biochemical analysis was done by HPLC-TLC and radiolabelled enzyme assay. The promoter of the WsSGTL1 gene was cloned by using Genome Walker kit (Clontech, USA and the 3D structures were predicted by using Discovery Studio Ver. 2.5. RESULTS: The WsSGTL1 transgenic plants were confirmed to be single copy by Southern and homozygous by segregation analysis. As compared to WT, the transgenic plants showed better germination, salt tolerance, heat and cold tolerance. The level of the transgene WsSGTL1 was elevated in heat, cold and salt stress along with other marker genes such as HSP70, HSP90, RD29, SOS3 and LEA4-5. Biochemical analysis showed the formation of sterol glycosides and increase in enzyme activity. When the promoter of WsSGTL1 gene was cloned from W. somnifera and sequenced, it contained stress responsive elements. Bioinformatics analysis of the 3D structure of the WsSGTL1 protein showed functional similarity with sterol glycosyltransferase AtSGT of A. thaliana. CONCLUSIONS: Transformation of WsSGTL1 gene in A. thaliana conferred abiotic stress tolerance. The promoter of the gene in W.somnifera was found

  8. Overexpression of WsSGTL1 Gene of Withania somnifera Enhances Salt Tolerance, Heat Tolerance and Cold Acclimation Ability in Transgenic Arabidopsis Plants

    Science.gov (United States)

    Mishra, Manoj K.; Chaturvedi, Pankaj; Singh, Ruchi; Singh, Gaurav; Sharma, Lokendra K.; Pandey, Vibha; Kumari, Nishi; Misra, Pratibha

    2013-01-01

    Background Sterol glycosyltrnasferases (SGT) are enzymes that glycosylate sterols which play important role in plant adaptation to stress and are medicinally important in plants like Withania somnifera. The present study aims to find the role of WsSGTL1 which is a sterol glycosyltransferase from W. somnifera, in plant’s adaptation to abiotic stress. Methodology The WsSGTL1 gene was transformed in Arabidopsis thaliana through Agrobacterium mediated transformation, using the binary vector pBI121, by floral dip method. The phenotypic and physiological parameters like germination, root length, shoot weight, relative electrolyte conductivity, MDA content, SOD levels, relative electrolyte leakage and chlorophyll measurements were compared between transgenic and wild type Arabidopsis plants under different abiotic stresses - salt, heat and cold. Biochemical analysis was done by HPLC-TLC and radiolabelled enzyme assay. The promoter of the WsSGTL1 gene was cloned by using Genome Walker kit (Clontech, USA) and the 3D structures were predicted by using Discovery Studio Ver. 2.5. Results The WsSGTL1 transgenic plants were confirmed to be single copy by Southern and homozygous by segregation analysis. As compared to WT, the transgenic plants showed better germination, salt tolerance, heat and cold tolerance. The level of the transgene WsSGTL1 was elevated in heat, cold and salt stress along with other marker genes such as HSP70, HSP90, RD29, SOS3 and LEA4-5. Biochemical analysis showed the formation of sterol glycosides and increase in enzyme activity. When the promoter of WsSGTL1 gene was cloned from W. somnifera and sequenced, it contained stress responsive elements. Bioinformatics analysis of the 3D structure of the WsSGTL1 protein showed functional similarity with sterol glycosyltransferase AtSGT of A. thaliana. Conclusions Transformation of WsSGTL1 gene in A. thaliana conferred abiotic stress tolerance. The promoter of the gene in W.somnifera was found to have stress

  9. ATR-FTIR spectroscopy reveals involvement of lipids and proteins of intact pea pollen grains to heat stress tolerance

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    Rachid eLahlali

    2014-12-01

    Full Text Available With climate change, pea will be more frequently subjected to heat stress in semi-arid regions like Saskatchewan during flowering. The pollen germination percentage of two pea cultivars was reduced by heat stress (36°C with an important decrease in cultivar ‘CDC Golden’ compared to ‘CDC Sage’. Lipids, protein and other pollen coat compositions of whole intact pollen grains of both pea cultivars were investigated using mid infrared (mid-IR Attenuated Total Reflectance (ATR-Fourier Transform Infrared (FTIR spectroscopy. Curve-fitting of ATR absorbance spectra in the protein region enabled estimation and comparison of different protein secondary structures between the two cultivars. CDC Sage had relatively greater amounts of α-helical structures (48.6-43.6%; band at 1654 cm-1 and smaller amounts of β-sheets (41.3-46% than CDC Golden. The CDC Golden had higher amounts of β-sheets (46.3-51.7% compared to α-helical structures (35.3-36.2%. Further, heat stress resulted in prominent changes in the symmetrical and asymmetrical CH2 bands from lipid acyl chain, ester carbonyl band, and carbohydrate region. The intensity of asymmetric and symmetric CH2 vibration of heat stressed CDC Golden was reduced considerably in comparison to the control and the decrease was higher compared to CDC sage. In addition, CDC Golden showed an increase in intensity at the oxidative band of 3015 cm-1. These results reveal that the whole pollen grains of both pea cultivars responded differently to heat stress. The tolerance of CDC Sage to heat stress (expressed as pollen germination percentage may be due to its protein richness with α-helical structures which would protect against the destructive effects of dehydration due to heat stress. The low pollen germination percentage of CDC Golden after heat stress may be also due to its sensitivity to lipid changes due to heat stress.

  10. ATR-FTIR spectroscopy reveals involvement of lipids and proteins of intact pea pollen grains to heat stress tolerance.

    Science.gov (United States)

    Lahlali, Rachid; Jiang, Yunfei; Kumar, Saroj; Karunakaran, Chithra; Liu, Xia; Borondics, Ferenc; Hallin, Emil; Bueckert, Rosalind

    2014-01-01

    With climate change, pea will be more frequently subjected to heat stress in semi-arid regions like Saskatchewan during flowering. The pollen germination percentage of two pea cultivars was reduced by heat stress (36°C) with an important decrease in cultivar 'CDC Golden' compared to 'CDC Sage.' Lipids, protein and other pollen coat compositions of whole intact pollen grains of both pea cultivars were investigated using mid infrared (mid-IR) attenuated total reflectance (ATR)-Fourier transform infrared (FTIR) spectroscopy. Curve fitting of ATR absorbance spectra in the protein region enabled estimation and comparison of different protein secondary structures between the two cultivars. CDC Sage had relatively greater amounts of α-helical structures (48.6-43.6%; band at 1654 cm(-1)) and smaller amounts of β-sheets (41.3-46%) than CDC Golden. The CDC Golden had higher amounts of β-sheets (46.3-51.7%) compared to α-helical structures (35.3-36.2%). Further, heat stress resulted in prominent changes in the symmetrical and asymmetrical CH2 bands from lipid acyl chain, ester carbonyl band, and carbohydrate region. The intensity of asymmetric and symmetric CH2 vibration of heat stressed CDC Golden was reduced considerably in comparison to the control and the decrease was higher compared to CDC Sage. In addition, CDC Golden showed an increase in intensity at the oxidative band of 3015 cm(-1). These results reveal that the whole pollen grains of both pea cultivars responded differently to heat stress. The tolerance of CDC Sage to heat stress (expressed as pollen germination percentage) may be due to its protein richness with α-helical structures which would protect against the destructive effects of dehydration due to heat stress. The low pollen germination percentage of CDC Golden after heat stress may be also due to its sensitivity to lipid changes due to heat stress.

  11. Over-expression of SlJA2 decreased heat tolerance of transgenic tobacco plants via salicylic acid pathway.

    Science.gov (United States)

    Liu, Zhong-Ming; Yue, Meng-Meng; Yang, Dong-Yue; Zhu, Shao-Bo; Ma, Na-Na; Meng, Qing-Wei

    2017-04-01

    Over-expression of SlJA2 decreased the accumulation of SA, which resulted in significant physiological and gene expression changes in transgenic tobacco plants, leading to the decreased heat tolerance of transgenic tobacco. NAC family, the largest transcription factors in plants, responses to different environmental stimuli. Here, we isolated a typical NAC transcription factor (SlJA2) from tomato and got transgenic tobacco with SlJA2 over-expression. Expression of SlJA2 was induced by heat stress (42 °C), chilling stress (4 °C), drought stress, osmotic stress, abscisic acid, and salicylic acid. Over-expression of SlJA2 decreased the accumulation of salicylic acid by regulating expression of salicylic acid degradation gene under heat stress. Compared to WT plants, stomatal apertures and water loss increased in transgenic plants, and the damage of photosynthetic apparatus and chlorophyll breakdown were more serious in transgenic plants under heat stress. Meanwhile, more H 2 O 2 and O 2 ·- were accumulated transgenic plants and proline synthesis was restricted, which resulted in more serious oxidative damage compared to WT. qRT-PCR analysis showed that over-expression of SlJA2 could down-regulate genes involved in reactive oxygen species scavenging, proline biosynthesis, and response to heat stress. All the above results indicated that SlJA2 may be a negative regulator responded to plant's heat tolerance. Thus, this study provides new insight into roles of NAC family member in plant response to abiotic stress.

  12. Molecular regulation and physiological functions of a novel FaHsfA2c cloned from tall fescue conferring plant tolerance to heat stress.

    Science.gov (United States)

    Wang, Xiuyun; Huang, Wanlu; Liu, Jun; Yang, Zhimin; Huang, Bingru

    2017-02-01

    Heat stress transcription factors (HSFs) compose a large gene family, and different members play differential roles in regulating plant responses to abiotic stress. The objectives of this study were to identify and characterize an A2-type HSF, FaHsfA2c, in a cool-season perennial grass tall fescue (Festuca arundinacea Schreb.) for its association with heat tolerance and to determine the underlying physiological functions and regulatory mechanisms of FaHsfA2c imparting plant tolerance to heat stress. FaHsfA2c was localized in nucleus and exhibited a rapid transcriptional increase in leaves and roots during early phase of heat stress. Ectopic expression of FaHsfA2c improved basal and acquired thermotolerance in wild-type Arabidopsis and also restored heat-sensitive deficiency of hsfa2 mutant. Overexpression of FaHsfA2c in tall fescue enhanced plant tolerance to heat by triggering transcriptional regulation of heat-protective gene expression, improving photosynthetic capacity and maintaining plant growth under heat stress. Our results indicated that FaHsfA2c acted as a positive regulator conferring thermotolerance improvement in Arabidopsis and tall fescue, and it could be potentially used as a candidate gene for genetic modification and molecular breeding to develop heat-tolerant cool-season grass species. © 2016 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

  13. A comprehensive assessment of geographic variation in heat tolerance and hardening capacity in populations of Drosophila melanogaster from eastern Australia

    DEFF Research Database (Denmark)

    Sgrò, C M; Overgaard, J; Kristensen, T N

    2010-01-01

    We examined latitudinal variation in adult and larval heat tolerance in Drosophila melanogaster from eastern Australia. Adults were assessed using static and ramping assays. Basal and hardened static heat knockdown time showed significant linear clines; heat tolerance increased towards the tropics......, particularly for hardened flies, suggesting that tropical populations have a greater hardening response. A similar pattern was evident for ramping heat knockdown time at 0.06 °C min-1 increase. There was no cline for ramping heat knockdown temperature (CTmax) at 0.1 °C min-1 increase. Acute (static) heat...... resistance depend on assay methods. Genetic correlations in thermotolerance across life stages and evolutionary potential for critical thermal limits should be the focus of future studies....

  14. Hydrogen sulfide acts as a downstream signal molecule in salicylic acid-induced heat tolerance in maize (Zea mays L.) seedlings.

    Science.gov (United States)

    Li, Zhong-Guang; Xie, Lin-Run; Li, Xiao-Juan

    2015-04-01

    Salicylic acid (SA), 2-hydroxy benzoic acid, is a small phenolic compound with multifunction that is involved in plant growth, development, and the acquisition of stress tolerance. In recent years, hydrogen sulfide (H2S) has been found to have similar functions, but cross talk between SA and H2S in the acquisition of heat tolerance is not clear. In this study, pretreatment of maize seedlings with SA improved the survival percentage of seedlings under heat stress, indicating that SA pretreatment could improve the heat tolerance of maize seedlings. In addition, treatment with SA enhanced the activity of L-cysteine desulfhydrase (L-DES), a key enzyme in H2S biosynthesis, which in turn induced accumulation of endogenous H2S. Interestingly, SA-induced heat tolerance was enhanced by addition of NaHS, a H2S donor, but weakened by specific inhibitors of H2S biosynthesis DL-propargylglycine (PAG) and its scavenger hydroxylamine (HT). Furthermore, pretreatment with paclobutrazol (PAC) and 2-aminoindan-2-phosphonic acid (AIP), inhibitors of SA biosynthesis, had no significant effect on NaHS-induced heat tolerance of maize seedlings. Similarly, significant change in the activities of phenylalanine ammonia lyase (PAL) and benzoic-acid-2-hydroxylase (BA2H), the key enzymes in SA biosynthesis, and the content of endogenous SA, was not observed in maize seedlings by NaHS treatment. All of the above-mentioned results suggest that SA pretreatment could improve the heat tolerance of maize seedlings, and H2S might be a novel downstream signal molecule in SA-induced heat tolerance. Copyright © 2015 Elsevier GmbH. All rights reserved.

  15. T Cell-Mediated Chronic Inflammatory Diseases Are Candidates for Therapeutic Tolerance Induction with Heat Shock Proteins

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    Ariana Barbera Betancourt

    2017-10-01

    Full Text Available Failing immunological tolerance for critical self-antigens is the problem underlying most chronic inflammatory diseases of humans. Despite the success of novel immunosuppressive biological drugs, the so-called biologics, in the treatment of diseases such rheumatoid arthritis (RA and type 1 diabetes, none of these approaches does lead to a permanent state of medicine free disease remission. Therefore, there is a need for therapies that restore physiological mechanisms of self-tolerance. Heat shock proteins (HSPs have shown disease suppressive activities in many models of experimental autoimmune diseases through the induction of regulatory T cells (Tregs. Also in first clinical trials with HSP-based peptides in RA and diabetes, the induction of Tregs was noted. Due to their exceptionally high degree of evolutionary conservation, HSP protein sequences (peptides are shared between the microbiota-associated bacterial species and the self-HSP in the tissues. Therefore, Treg mechanisms, such as those induced and maintained by gut mucosal tolerance for the microbiota, can play a role by targeting the more conserved HSP peptide sequences in the inflamed tissues. In addition, the stress upregulated presence of HSP in these tissues may well assist the targeting of the HSP induced Treg specifically to the sites of inflammation.

  16. Recession-Tolerant Heat Flux Sensors for Thermal Protection Systems Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Phase I project will develop a suite of diagnostic sensors using Direct Write technology to measure temperature, surface recession depth, and heat flux of an...

  17. Impact Of Phenylpropanoid Compounds On Heat Stress Tolerance In Carrot Cell Cultures

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    Mauro Commisso

    2016-09-01

    Full Text Available ABSTRACTThe phenylpropanoid and flavonoid families include thousands of specialized metabolites that influence a wide range of processes in plants, including seed dispersal, auxin transport, photoprotection, mechanical support and protection against insect herbivory. Such metabolites play a key role in the protection of plants against abiotic stress, in many cases through their well-known ability to inhibit the formation of reactive oxygen species (ROS. However, the precise role of specific phenylpropanoid and flavonoid molecules is unclear. We therefore investigated the role of specific anthocyanins (ACs and other phenylpropanoids that accumulate in carrot cells cultivated in vitro, focusing on their supposed ability to protect cells from heat stress. First we characterized the effects of heat stress to identify quantifiable morphological traits as markers of heat stress susceptibility. We then fed the cultures with precursors to induce the targeted accumulation of specific compounds, and compared the impact of heat stress in these cultures and unfed controls. Data modeling based on Projection to Latent Structures (PLS regression revealed that metabolites containing coumaric or caffeic acid, including ACs, correlate with less heat damage. Further experiments suggested that one of the cellular targets damaged by heat stress and protected by these metabolites is the actin microfilament cytoskeleton.

  18. Heat shock transcription factors involved in seed desiccation tolerance and longevity retard vegetative senescence in transgenic tobacco.

    Science.gov (United States)

    Almoguera, Concepción; Personat, José-María; Prieto-Dapena, Pilar; Jordano, Juan

    2015-08-01

    Transcription factors normally expressed in sunflower seeds delayed vegetative senescence induced by severe stress in transgenic tobacco. This revealed a novel connection between seed heat shock factors, desiccation tolerance and vegetative longevity. HaHSFA9 and HaHSFA4a coactivate a genetic program that, in sunflower (Helianthus annuus L.), contributes to seed longevity and desiccation tolerance. We have shown that overexpression of HaHSFA9 in transgenic tobacco seedlings resulted in tolerance to drastic dehydration and oxidative stress. Overexpression of HaHSFA9 alone was linked to a remarkable protection of the photosynthetic apparatus. In addition, the combined overexpression of HaHSFA9 and HaHSFA4a enhanced all these stress-resistance phenotypes. Here, we find that HaHSFA9 confers protection against damage induced by different stress conditions that accelerate vegetative senescence during different stages of development. Seedlings and plants that overexpress HaHSFA9 survived lethal treatments of dark-induced senescence. HaHSFA9 overexpression induced resistance to effects of culture under darkness for several weeks. Only some homoiochlorophyllous resurrection plants are able to withstand this experimental severe stress condition. The combined overexpression of HaHSFA9 and HaHSFA4a did not result in further slowing of dark-induced seedling senescence. However, combined expression of the two transcription factors caused improved recovery of the photosynthetic organs of seedlings after lethal dark treatments. At later stages of vegetative development, HaHSFA9 delayed the appearance of senescence symptoms in leaves of plants grown under normal illumination. This delay was observed under either control or stress treatments. Thus, HaHSFA9 delayed both natural and stress-induced leaf senesce. These novel observations connect transcription factors involved in desiccation tolerance with leaf longevity.

  19. Potential costs of acclimatization to a warmer climate: growth of a reef coral with heat tolerant vs. sensitive symbiont types.

    Directory of Open Access Journals (Sweden)

    Alison Jones

    Full Text Available One of the principle ways in which reef building corals are likely to cope with a warmer climate is by changing to more thermally tolerant endosymbiotic algae (zooxanthellae genotypes. It is highly likely that hosting a more heat-tolerant algal genotype will be accompanied by tradeoffs in the physiology of the coral. To better understand one of these tradeoffs, growth was investigated in the Indo-Pacific reef-building coral Acropora millepora in both the laboratory and the field. In the Keppel Islands in the southern Great Barrier Reef this species naturally harbors nrDNA ITS1 thermally sensitive type C2 or thermally tolerant type D zooxanthellae of the genus Symbiodinium and can change dominant type following bleaching. We show that under controlled conditions, corals with type D symbionts grow 29% slower than those with type C2 symbionts. In the field, type D colonies grew 38% slower than C2 colonies. These results demonstrate the magnitude of trade-offs likely to be experienced by this species as they acclimatize to warmer conditions by changing to more thermally tolerant type D zooxanthellae. Irrespective of symbiont genotype, corals were affected to an even greater degree by the stress of a bleaching event which reduced growth by more than 50% for up to 18 months compared to pre-bleaching rates. The processes of symbiont change and acute thermal stress are likely to act in concert on coral growth as reefs acclimatize to more stressful warmer conditions, further compromising their regeneration capacity following climate change.

  20. Potential costs of acclimatization to a warmer climate: growth of a reef coral with heat tolerant vs. sensitive symbiont types.

    Science.gov (United States)

    Jones, Alison; Berkelmans, Ray

    2010-05-03

    One of the principle ways in which reef building corals are likely to cope with a warmer climate is by changing to more thermally tolerant endosymbiotic algae (zooxanthellae) genotypes. It is highly likely that hosting a more heat-tolerant algal genotype will be accompanied by tradeoffs in the physiology of the coral. To better understand one of these tradeoffs, growth was investigated in the Indo-Pacific reef-building coral Acropora millepora in both the laboratory and the field. In the Keppel Islands in the southern Great Barrier Reef this species naturally harbors nrDNA ITS1 thermally sensitive type C2 or thermally tolerant type D zooxanthellae of the genus Symbiodinium and can change dominant type following bleaching. We show that under controlled conditions, corals with type D symbionts grow 29% slower than those with type C2 symbionts. In the field, type D colonies grew 38% slower than C2 colonies. These results demonstrate the magnitude of trade-offs likely to be experienced by this species as they acclimatize to warmer conditions by changing to more thermally tolerant type D zooxanthellae. Irrespective of symbiont genotype, corals were affected to an even greater degree by the stress of a bleaching event which reduced growth by more than 50% for up to 18 months compared to pre-bleaching rates. The processes of symbiont change and acute thermal stress are likely to act in concert on coral growth as reefs acclimatize to more stressful warmer conditions, further compromising their regeneration capacity following climate change.

  1. Food Legumes and Rising Temperatures: Effects, Adaptive Functional Mechanisms Specific to Reproductive Growth Stage and Strategies to Improve Heat Tolerance

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    Kumari Sita

    2017-10-01

    Full Text Available Ambient temperatures are predicted to rise in the future owing to several reasons associated with global climate changes. These temperature increases can result in heat stress- a severe threat to crop production in most countries. Legumes are well-known for their impact on agricultural sustainability as well as their nutritional and health benefits. Heat stress imposes challenges for legume crops and has deleterious effects on the morphology, physiology, and reproductive growth of plants. High-temperature stress at the time of the reproductive stage is becoming a severe limitation for production of grain legumes as their cultivation expands to warmer environments and temperature variability increases due to climate change. The reproductive period is vital in the life cycle of all plants and is susceptible to high-temperature stress as various metabolic processes are adversely impacted during this phase, which reduces crop yield. Food legumes exposed to high-temperature stress during reproduction show flower abortion, pollen and ovule infertility, impaired fertilization, and reduced seed filling, leading to smaller seeds and poor yields. Through various breeding techniques, heat tolerance in major legumes can be enhanced to improve performance in the field. Omics approaches unravel different mechanisms underlying thermotolerance, which is imperative to understand the processes of molecular responses toward high-temperature stress.

  2. Effects of radiational heating at low air temperature on water balance, cold tolerance, and visible injury of red spruce foliage.

    Science.gov (United States)

    Hadley, J L; Amundson, R G

    1992-07-01

    Recent studies have shown that winter needle mortality in red spruce (Picea rubens Sarg.) is increased by exposure to direct solar radiation, possibly as a result of photo-oxidative damage, accelerated winter desiccation, or reduced cold tolerance due to heating of sun-exposed needles. In an experiment at controlled subfreezing air temperatures of -10 to -20 degrees C, visible radiation was less effective than infrared radiation in producing needle desiccation and visible injury during freeze-thaw cycles. However, visible radiation produced a red-brown color in injured needles, similar to natural winter injury, whereas injured needles exposed to infrared radiation were yellow and injured needles kept in darkness were dark brown. Thus, visible radiation was necessary to produce the red-brown color of damaged needles, but not the injury itself. Needle desiccation was not strongly correlated with visible injury, but the pattern of variation in visible injury among trees and the positive correlation between electrolyte leakage and visible injury suggested that freezing damage following freeze-thaw cycles might cause the visible injury. This was confirmed by a second experiment that showed loss of cold hardiness in needles thawed by radiational heating for six consecutive days. Even with a constant nighttime temperature of -10 degrees C, six days of radiational heating of needles to above freezing caused a small (2.8 degrees C) mean decrease in needle cold tolerance, as measured by electrolyte leakage. Continuous darkness at -10 degrees C for six days resulted in an estimated 5.6 degrees C mean increase in needle cold tolerance. Freezing injury stimulated desiccation: cooling at 4 degrees C h(-1) to -43 or -48 degrees C increased the dehydration rate of isolated shoots by a factor of two to three during the first day after thawing. Within three days at 15 to 22 degrees C and 50% relative humidity, the mean water content of these shoots fell to 60% or lower, compared to

  3. BREEDING AND GENETICS SYMPOSIUM:Breeding heat tolerant dairy cattle: the case for introgression of the "slick" prolactin receptor variant into dairy breeds.

    Science.gov (United States)

    Davis, S R; Spelman, R J; Littlejohn, M D

    2017-04-01

    Increasing environmental temperatures are a threat to the sustainability of livestock production and, because of the high metabolic demands of lactation, to dairy production in particular. Summer heat waves in temperate climates reduce feed intake, milk production, and cow comfort. In extreme heat events, there is an increase in cow mortality. In tropical climates, dairy cattle are mostly (zebu) type or zebu crossbred with temperate dairy breeds. Crossbreeding is undertaken to combine the heat tolerance and tick resistance of zebu with the productivity of temperate dairy breeds. In the absence of improved heat tolerance, milk production and fertility of temperate cattle is severely impaired. We have recently identified a key role for the prolactin pathway in regulating heat tolerance. A de novo mutation in prolactin that impairs prolactin activity was discovered in hairy and heat intolerant, New Zealand dairy cattle. The phenotypes produced were remarkably similar to those seen in fescue toxicosis, a syndrome seen in grazing cattle in the U.S. where ingestion of ergovaline, a fungal toxin from infected pasture, inhibits prolactin secretion. Recognition of the role of prolactin in hairy cattle led us to identify a deletion in exon 10 of the long-form of the prolactin receptor in Senepol cattle that causes truncation of the protein and determines the slick coat and heat tolerance traits found in this , beef breed. The short form of the prolactin receptor is predicted to be unaffected by the deletion. Knowledge of this dominant mutation has provided the impetus to begin a crossbreeding program to investigate performance and heat tolerance of temperate dairy cattle carrying the slick, prolactin receptor variant. The perceived opportunity is to introgress this variant into temperate dairy cattle to enable performance and welfare improvement in hot climates. Heat tolerance of cattle with slick coats appears to be mostly associated with coat type although sweating ability

  4. Hand immersion in cold water alleviating physiological strain and increasing tolerance to uncompensable heat stress.

    Science.gov (United States)

    Khomenok, Gennadi A; Hadid, Amir; Preiss-Bloom, Orahn; Yanovich, Ran; Erlich, Tomer; Ron-Tal, Osnat; Peled, Amir; Epstein, Yoram; Moran, Daniel S

    2008-09-01

    The current study examines the use of hand immersion in cold water to alleviate physiological strain caused by exercising in a hot climate while wearing NBC protective garments. Seventeen heat acclimated subjects wearing a semi-permeable NBC protective garment and a light bulletproof vest were exposed to a 125 min exercise-heat stress (35 degrees C, 50% RH; 5 km/h, 5% incline). The heat stress exposure routine included 5 min rest in the chamber followed by two 50:10 min work-rest cycles. During the control trial (CO), there was no intervention, whilst in the intervention condition the subjects immersed their hands and forearms in a 10 degrees C water bath (HI). The results demonstrated that hand immersion in cold water significantly reduced physiological strain. In the CO exposure during the first and second resting periods, the average rectal temperature (T (re)) practically did not decrease. With hand immersion, the mean (SD) T (re) decreased by 0.45 (0.05 degrees C) and 0.48 degrees C (0.06 degrees C) during the first and second rest periods respectively (P immersion in cold water for 10 min is an effective method for decreasing the physiological strain caused by exercising under heat stress while wearing NBC protective garments. The method is convenient, simple, and allows longer working periods in hot or contaminated areas with shorter resting periods.

  5. Heat-Related Deaths in Hot Cities: Estimates of Human Tolerance to High Temperature Thresholds

    Directory of Open Access Journals (Sweden)

    Sharon L. Harlan

    2014-03-01

    Full Text Available In this study we characterized the relationship between temperature and mortality in central Arizona desert cities that have an extremely hot climate. Relationships between daily maximum apparent temperature (ATmax and mortality for eight condition-specific causes and all-cause deaths were modeled for all residents and separately for males and females ages <65 and ≥65 during the months May–October for years 2000–2008. The most robust relationship was between ATmax on day of death and mortality from direct exposure to high environmental heat. For this condition-specific cause of death, the heat thresholds in all gender and age groups (ATmax = 90–97 °F; 32.2‒36.1 °C were below local median seasonal temperatures in the study period (ATmax = 99.5 °F; 37.5 °C. Heat threshold was defined as ATmax at which the mortality ratio begins an exponential upward trend. Thresholds were identified in younger and older females for cardiac disease/stroke mortality (ATmax = 106 and 108 °F; 41.1 and 42.2 °C with a one-day lag. Thresholds were also identified for mortality from respiratory diseases in older people (ATmax = 109 °F; 42.8 °C and for all-cause mortality in females (ATmax = 107 °F; 41.7 °C and males <65 years (ATmax = 102 °F; 38.9 °C. Heat-related mortality in a region that has already made some adaptations to predictable periods of extremely high temperatures suggests that more extensive and targeted heat-adaptation plans for climate change are needed in cities worldwide.

  6. Heat-related deaths in hot cities: estimates of human tolerance to high temperature thresholds.

    Science.gov (United States)

    Harlan, Sharon L; Chowell, Gerardo; Yang, Shuo; Petitti, Diana B; Morales Butler, Emmanuel J; Ruddell, Benjamin L; Ruddell, Darren M

    2014-03-20

    In this study we characterized the relationship between temperature and mortality in central Arizona desert cities that have an extremely hot climate. Relationships between daily maximum apparent temperature (ATmax) and mortality for eight condition-specific causes and all-cause deaths were modeled for all residents and separately for males and females ages <65 and ≥ 65 during the months May-October for years 2000-2008. The most robust relationship was between ATmax on day of death and mortality from direct exposure to high environmental heat. For this condition-specific cause of death, the heat thresholds in all gender and age groups (ATmax = 90-97 °F; 32.2-36.1 °C) were below local median seasonal temperatures in the study period (ATmax = 99.5 °F; 37.5 °C). Heat threshold was defined as ATmax at which the mortality ratio begins an exponential upward trend. Thresholds were identified in younger and older females for cardiac disease/stroke mortality (ATmax = 106 and 108 °F; 41.1 and 42.2 °C) with a one-day lag. Thresholds were also identified for mortality from respiratory diseases in older people (ATmax = 109 °F; 42.8 °C) and for all-cause mortality in females (ATmax = 107 °F; 41.7 °C) and males <65 years (ATmax = 102 °F; 38.9 °C). Heat-related mortality in a region that has already made some adaptations to predictable periods of extremely high temperatures suggests that more extensive and targeted heat-adaptation plans for climate change are needed in cities worldwide.

  7. Microhabitat and body size effects on heat tolerance: implications for responses to climate change (army ants: Formicidae, Ecitoninae).

    Science.gov (United States)

    Baudier, Kaitlin M; Mudd, Abigail E; Erickson, Shayna C; O'Donnell, Sean

    2015-09-01

    1. Models that predict organismal and population responses to climate change may be improved by considering ecological factors that affect species thermal tolerance. Species differences in microhabitat use can expose animals to diverse thermal selective environments at a given site and may cause sympatric species to evolve different thermal tolerances. 2. We tested the hypothesis that species differences in body size and microhabitat use (above- vs. below-ground activity) would correspond to differences in thermal tolerance (maximum critical temperatures: CTmax ). Thermal buffering effects of soil can reduce exposure to extreme high temperatures for below-ground active species. We predicted larger-bodied individuals and species would have higher CTmax and that species mean CTmax would covary positively with degree of above-ground activity. We used Neotropical army ants (Formicidae: Ecitoninae) as models. Army ants vary in microhabitat use from largely subterranean to largely above-ground active species and are highly size polymorphic. 3. We collected data on above- and below-ground temperatures in habitats used by army ants to test for microhabitat temperature differences, and we conducted CTmax assays for army ant species with varying degrees of surface activity and with different body sizes within and between species. We then tested whether microhabitat use was associated with species differences in CTmax and whether microhabitat was a better predictor of CTmax than body size for species that overlapped in size. 4. Microhabitat use was a highly significant predictor of species' upper thermal tolerance limits, both for raw data and after accounting for the effects of phylogeny. Below-ground species were more thermally sensitive, with lower maximum critical temperatures (CTmax ). The smallest workers within each species were the least heat tolerant, but the magnitude of CTmax change with body size was greater in below-ground species. Species-typical microhabitat

  8. Extremely heat tolerant photo-symbiosis in a shallow marine benthic foraminifera

    Science.gov (United States)

    Schmidt, C.; Titelboim, D.; Brandt, J.; Herut, B.; Abramovich, S.; Almogi-Labin, A.; Kucera, M.

    2016-08-01

    Bleaching, the loss of algal symbionts, occurs in marine photosymbiotic organisms at water temperatures minimally exceeding average summer SST (sea surface temperatures). Pre-adaptation allows organisms to persist under warmer conditions, providing the tolerance can be carried to new habitats. Here we provide evidence for the existence of such adaptation in the benthic foraminifera Pararotalia calcariformata. This species occurs at a thermally polluted site in the Mediterranean, where water temperatures reach a maxima daily average of 36 °C during the summer. To test whether this occurrence represents a widespread adaptation, we conducted manipulative experiments exposing this species from an unpolluted site to elevated temperatures (20-42 °C). It was kept in co-culture with the more thermally sensitive foraminifera Amphistegina lobifera in two experiments (20-36 °C). Reduced photosynthetic activity in A. lobifera occurred at 32 °C whereas photochemical stress in P. calcariformata was first observed during exposure to 36 °C. Pararotalia calcariformata survived all treatment conditions and grew under 36 °C. The photosymbiosis in P. calcariformata is unusually thermally tolerant. These observations imply that marine eukaryote-eukaryote photosymbiosis can respond to elevated temperatures by drawing on a pool of naturally occurring pre-adaptations. It also provides a perspective on the massive occurrence of symbiont-bearing foraminifera in the early Cenozoic hothouse climate.

  9. Enhancing heat tolerance of the little dogwood Cornus canadensis L. f. with introduction of a superoxide reductase gene from the hyperthermophilic archaeon Pyrococcus furiosus

    Directory of Open Access Journals (Sweden)

    Xinmin eGeng

    2016-01-01

    Full Text Available Production of reactive oxygen species (ROS can be accelerated under various biotic and abiotic stresses causing lipid peroxidation, protein degradation, enzyme inactivation, and DNA damage. Superoxide reductase (SOR is a novel antioxidant enzyme from Pyrococcus furiosus and is employed by this anaerobic hyperthermophilic archaeon for efficient detoxification of ROS. In this study, SOR was introduced into a flowering plant Cornus canadensis to enhance its heat tolerance and reduce heat induced damage. A fusion construct of the SOR gene and Green Fluorescent Protein gene (GFP was introduced into C. canadensis using Agrobacterium-mediated transformation. Heat tolerance of the GFP-SOR expressing transgenic plants was investigated by observing morphological symptoms of heat injury and by examining changes in photosynthesis, malondialdehyde (MDA, and proline levels in the plants. Our results indicate that the expression of the P. furiosus SOR gene in the transgenic plants alleviated lipid peroxidation of cell membranes and photoinhibition of PS II, and decreased the accumulation of proline at 40°C. After a series of exposures to increasing temperatures, the SOR transgenic plants remained healthy and green whereas most of the non-transgenic plants dried up and were unable to recover. While it had previously been reported that expression of SOR in Arabidopsis enhanced heat tolerance, this is the first report of the successful demonstration of improved heat tolerance in a non-model plant resulting from the introduction of P. furiosus SOR. The study demonstrates the potential of SOR for crop improvement and that inherent limitations of plant heat tolerance can be ameliorated with P. furiosus SOR.

  10. The Next-Generation Goddard Convective-Stratiform Heating Algorithm: Addressing Higher Latitude, Cold Season, and Synoptic Systems

    Science.gov (United States)

    Wu, D.; Tao, W. K.; Lang, S. E.

    2016-12-01

    The Goddard Convective-Stratiform Heating (or CSH) algorithm is used to retrieve estimates of cloud heating over the global Tropics using TRMM rainfall data and a set of look-up-tables (LUTs) derived from a series of multi-week cloud-resolving model (CRM) simulations using the Goddard Cumulus Ensemble model (or GCE). These simulations link satellite observables (i.e., surface rainfall and stratiform fraction) with cloud heating profiles, which are not directly observable. The current CSH LUTs are differentiated with respect to surface rainfall characteristics, which is effective for tropical and continental summertime environments. However, with the launch of GPM in 2014, the range over which such algorithms can be applied has been extended from the Tropics and mid-latitudes to higher latitudes, including cold season and synoptic weather systems. Accordingly, the CSH algorithm and LUTs need to be updated for higher latitude events. In this study, NU-WRF was employed at 1 km to simulate winter systems in the US. A, new methodology has been adopted to construct LUTs utilizing satellite-observable 3D intensity fields, such as radar reflectivity. The new methodology/LUTs can be then applied to simulated radar fields to derive cloud heating for comparison against the model simulated heating. The model heating is treated as the `truth' as it is self-consistent with the simulated radar fields. This `consistency check' approach is a common well-established first step in algorithm development (e.g., the earlier CSH). The LUTs will be improved by iterating the consistency checks to quantitatively evaluate the similarities between the retrieved and simulated heating. The evaluations will be performed for different weather events, including northeast winter storms and atmospheric rivers.

  11. Enhanced butyric acid tolerance and production by Class I heat shock protein-overproducing Clostridium tyrobutyricum ATCC 25755.

    Science.gov (United States)

    Suo, Yukai; Luo, Sheng; Zhang, Yanan; Liao, Zhengping; Wang, Jufang

    2017-08-01

    The response of Clostridium tyrobutyricum to butyric acid stress involves various stress-related genes, and therefore overexpression of stress-related genes can improve butyric acid tolerance and yield. Class I heat shock proteins (HSPs) play an important role in the process of protecting bacteria from sudden changes of extracellular stress by assisting protein folding correctly. The results of quantitative real-time PCR indicated that the Class I HSGs grpE, dnaK, dnaJ, groEL, groES, and htpG were significantly upregulated under butyric acid stress, especially the dnaK and groE operons. Overexpression of groESL and htpG could significantly improve the tolerance of C. tyrobutyricum to butyric acid, while overexpression of dnaK and dnaJ showed negative effects on butyric acid tolerance. Acid production was also significantly promoted by increased GroESL expression levels; the final butyric acid and acetic acid concentrations were 28.2 and 38% higher for C. tyrobutyricum ATCC 25755/groESL than for the wild-type strain. In addition, when fed-batch fermentation was carried out using cell immobilization in a fibrous-bed bioreactor, the butyric acid yield produced by C. tyrobutyricum ATCC 25755/groESL reached 52.2 g/L, much higher than that for the control. The improved butyric acid yield is probably attributable to the high GroES and GroEL levels, which can stabilize the biosynthetic machinery of C. tyrobutyricum under extracellular butyric acid stress.

  12. Non-lethal heat shock increased Hsp70 and immune protein transcripts but not Vibrio tolerance in the white-leg shrimp.

    Directory of Open Access Journals (Sweden)

    Nguyen Hong Loc

    Full Text Available Non-lethal heat shock boosts bacterial and viral disease tolerance in shrimp, possibly due to increases in endogenous heat shock protein 70 (Hsp70 and/or immune proteins. To further understand the mechanisms protecting shrimp against infection, Hsp70 and the mRNAs encoding the immune-related proteins prophenoloxidase (proPO, peroxinectin, penaeidin, crustin and hemocyanin were studied in post-larvae of the white-leg shrimp Litopenaeus vannamei, following a non-lethal heat shock. As indicated by RT-qPCR, a 30 min abrupt heat shock increased Hsp70 mRNA in comparison to non-heated animals. Immunoprobing of western blots and quantification by ELISA revealed that Hsp70 production after heat shock was correlated with enhanced Hsp70 mRNA. proPO and hemocyanin mRNA levels were augmented, whereas peroxinectin and crustin mRNA levels were unchanged following non-lethal heat shock. Penaeidin mRNA was decreased by all heat shock treatments. Thirty min abrupt heat shock failed to improve survival of post-larvae in a standardized challenge test with Vibrio harveyi, indicating that under the conditions of this study, L. vannamei tolerance to Vibrio infection was influenced neither by Hsp70 accumulation nor the changes in the immune-related proteins, observations dissimilar to other shrimp species examined.

  13. High systemic and testicular thermolytic efficiency during heat tolerance test reflects better semen quality in rams of tropical breeds

    Science.gov (United States)

    Kahwage, Priscila Reis; Esteves, Sérgio Novita; Jacinto, Manuel Antônio Chagas; Junior, Waldomiro Barioni; Pezzopane, José Ricardo Macedo; de Andrade Pantoja, Messy Hannear; Bosi, Cristian; Miguel, Maria Carolina Villani; Mahlmeister, Kaue; Garcia, Alexandre Rossetto

    2017-10-01

    This study aimed to assess the capacity of Morada Nova (MN) and Santa Inês (SIN) rams to maintain body and testicular homeothermy under thermal challenge. For 5 days in the summer, 16 males (SIN = 7 and MN = 9) underwent a heat tolerance test, i.e., period 1—animals maintained in the shade (11 to 12 h); period 2—animals exposed to sunlight (12 to 13 h); and period 3—animals returned to the shade (13 to 14 h). The respiratory rate, heart rate, rectal temperature, and infrared surface temperatures (IRT) of the trunk, back, eyeball, and testicles were assessed in each period. The index of capacity of tolerance to insolation (ICTI), which indicates the animals' level of adaptability, was calculated for each animal. Semen quality and testicular parenchyma integrity were assessed before and after the thermal challenge. Statistical analyses were performed at 5% significance. In period 1, the variables had baseline values for both genotypes. In period 2, the variables involved in thermolysis significantly increased ( P animals were considered resilient to a thermal challenge. In addition, infrared thermography was an efficient tool to verify body and testicular thermoregulation.

  14. Can butterflies evade fire? Pupa location and heat tolerance in fire prone habitats of Florida.

    Science.gov (United States)

    Thom, Matthew D; Daniels, Jaret C; Kobziar, Leda N; Colburn, Jonathan R

    2015-01-01

    Butterflies such as the atala hairstreak, Eumaeus atala Poey, and the frosted elfin, Callophrys irus Godart, are restricted to frequently disturbed habitats where their larval host plants occur. Pupae of these butterflies are noted to reside at the base of host plants or in the leaf litter and soil, which may allow them to escape direct mortality by fire, a prominent disturbance in many areas they inhabit. The capacity of these species to cope with fire is a critical consideration for land management and conservation strategies in the locations where they are found. Survival of E. atala pupae in relation to temperature and duration of heat pulse was tested using controlled water bath experiments and a series of prescribed fire field experiments. Survival of E. atala pupae was correlated to peak temperature and heat exposure in both laboratory and field trials. In addition, E. atala survival following field trials was correlated to depth of burial; complete mortality was observed for pupae at the soil surface. Fifty percent of E. atala survived the heat generated by prescribed fire when experimentally placed at depths ≥ 1.75 cm, suggesting that pupation of butterflies in the soil at depth can protect from fatal temperatures caused by fire. For a species such as E. atala that pupates above ground, a population reduction from a burn event is a significant loss, and so decreasing the impact of prescribed fire on populations is critical.

  15. The Mass-to-Surface Area Index of Heat Tolerance in a Large Cohort

    Science.gov (United States)

    1988-10-19

    Area Code) 22c. OFFICE SYMP9L Armstrong, Lawrence E., Ph.D. 508-651-4873 SGRD-UE-HR DD Form 1473, JUN 86 Prevous edtions a obolte. SECURITY l SIFICATION...on Authors: Lawrence E. Armstrong By Jane P. De Luca Ui!,t. ibit ,, Elaine L . Christensen A . Cr.dc, Roger W. Hubbard it Institution: Heat Research...suggested by Wallman and Hogdon (33). Due to relatively small sample sizes, races other than white or black were combined in the category named other

  16. Tritiated-water heat-tolerance index to predict the growth rate in calves in hot deserts

    International Nuclear Information System (INIS)

    Kamal, T.H.

    1982-01-01

    It was the intention of this study to develop a heat-tolerance index that predicts at an early age the growth rate of calves in a hot desert area (Inshas). Twelve female Friesian calves aged 13-15 months were maintained in climatic chambers for 2 weeks at a mild climate (control), followed by 2 weeks at a hot climate (experimental). Determinations of body water content, body solids, body weight and final rectal temperature were undertaken during the second week of the control and experimental periods. Afterwards the animals were transferred to the farm and maintained outdoors; they were weighed at the end of the 4 summer months. Body water content and rectal temperature were 9.47 and 2.42%, respectively, higher in the hot climate than in the control at P 1 ) or body solids content (X 2 ) that had occurred previously during the 2-weeks heat stress in the climatic chamber by using the equation Y = 39.44 - 1.65X 1 or Y = 45.02 - 1.27X 2 . The standard errors of the regression coefficients for the two equations were 0.094 and 0.132, respectively. The standard errors of the predicted Y for the two equations were 0.207 and 0.218, respectively

  17. Infrared thermography as a method for evaluating the heat tolerance in dairy cows

    Directory of Open Access Journals (Sweden)

    Darlene dos Santos Daltro

    Full Text Available ABSTRACT The objective of this study was to determine whether infrared thermography is a useful tool for the recognition of dairy cows in a state of thermal heat stress, as well as to identify the best region of the animal to be evaluated for this recognition. Physiological variables, including rectal temperature, respiratory frequency, cardiac frequency, and panting score were recorded in 38 lactating cows. For the assessment of environmental parameters, a digital black globe thermometer (TGD-200 model was used. Thermographic photographs of different regions of the body of cows were taken using an infrared camera (FLIR® System T300 and indicated respective superficial temperature. Physiological variables and superficial body temperature in different regions varied between genetic groups (Girolando: ½ Holstein × ½ Gir and ¾ Holstein × ¼ Gir; purebred Holstein. The environmental temperature ranged from 20.7 to 37.9 °C with a relative humidity reaching 95%. The mean rectal temperature (40.84 °C, respiratory frequency (111.36 breaths/min, and cardiac frequency (99.22 beats/min were higher for pure Holstein than for Girolando cows. Positive correlations were found between the physiological parameters and thermographic measures. The highest positive correlation (0.74 was found between the temperature in the lateral region of the udder and rectal temperature. Thermography is a good indicator of thermal comfort. The best region to identify heat stress in cows using thermography is the lateral region of the udder.

  18. Simulating extreme environments: Ergonomic evaluation of Chinese pilot performance and heat stress tolerance.

    Science.gov (United States)

    Li, Jing; Tian, Yinsheng; Ding, Li; Zou, Huijuan; Ren, Zhaosheng; Shi, Liyong; Feathers, David; Wang, Ning

    2015-06-05

    High-temperatures in the cockpit environment can adversely influence pilot behavior and performance. To investigate the impact of high thermal environments on Chinese pilot performance in a simulated cockpit environment. Ten subjects volunteered to participate in the tests under 40°C and 45°C high-temperature simulations in an environmentally controlled chamber. Measures such as grip strength, perception, dexterity, somatic sense reaction, and analytical reasoning were taken. The results were compared to the Combined Index of Heat Stress (CIHS). CIHS exceeded the heat stress safety limit after 45 min under 40°C, grip strength decreased by 12% and somatic perception became 2.89 times larger than the initial value. In the case of 45°C, CIHS exceeded the safety limit after only 20 min, while the grip strength decreased just by 3.2% and somatic perception increased to 4.36 times larger than the initial value. Reaction and finger dexterity were not statistically different from baseline measurements, but the error rate of analytical reasoning test rose remarkably. Somatic perception was the most sensitive index to high-temperature, followed by grip strength. Results of this paper may help to improve environmental control design of new fighter cockpit and for pilot physiology and cockpit environment ergonomics research for Chinese pilots.

  19. Trehalose metabolism is important for heat stress tolerance and spore germination of Botrytis cinerea.

    Science.gov (United States)

    Doehlemann, Gunther; Berndt, Patrick; Hahn, Matthias

    2006-09-01

    To analyse the role of trehalose as stress protectant and carbon storage compound in the grey mould fungus Botrytis cinerea, mutants defective in trehalose-6-phosphate synthase (TPS1) and neutral trehalase (TRE1) were constructed. The Deltatps1 mutant was unable to synthesize trehalose, whereas the Deltatre1 mutant showed elevated trehalose levels compared to the wild-type and was unable to mobilize trehalose during conidial germination. Both mutants showed normal vegetative growth and were not affected in plant pathogenicity. Growth of the Deltatps1 mutant was more heat sensitive compared to the wild-type. Similarly, Deltatps1 conidia showed a shorter survival under heat stress, and their viability at moderate temperatures was strongly reduced. In germinating wild-type conidia, rapid trehalose degradation occurred only when germination was induced in the presence of nutrients. In contrast, little trehalose breakdown was observed during germination on hydrophobic surfaces in water. Here, addition of cAMP to conidia induced trehalose mobilization and accelerated the germination process, probably by activation of TRE1. In accordance with these data, both mutants showed germination defects only in the presence of sugars but not on hydrophobic surfaces in the absence of nutrients. The data indicate that in B. cinerea trehalose serves as a stress protectant, and also as a significant but not essential carbon source for germination when external nutrients are low. In addition, evidence was obtained that trehalose 6-phosphate plays a role as a regulator of glycolysis during germination.

  20. Production of the small heat shock protein Lo18 from Oenococcus oeni in Lactococcus lactis improves its stress tolerance.

    Science.gov (United States)

    Weidmann, Stéphanie; Maitre, Magali; Laurent, Julie; Coucheney, Françoise; Rieu, Aurélie; Guzzo, Jean

    2017-04-17

    Lactococcus lactis is a lactic acid bacterium widely used in cheese and fermented milk production. During fermentation, L. lactis is subjected to acid stress that impairs its growth. The small heat shock protein (sHsp) Lo18 from the acidophilic species Oenococcus oeni was expressed in L. lactis. This sHsp is known to play an important role in protein protection and membrane stabilization in O. oeni. The role of this sHsp could be studied in L. lactis, since no gene encoding for sHsp has been detected in this species. L. lactis subsp. cremoris strain MG1363 was transformed with the pDLhsp18 plasmid, which is derived from pDL278 and contains the hsp18 gene (encoding Lo18) and its own promoter sequence. The production of Lo18 during stress conditions was checked by immunoblotting and the cellular distribution of Lo18 in L. lactis cells after heat shock was determined. Our results clearly indicated a role for Lo18 in cytoplasmic protein protection and membrane stabilization during stress. The production of sHsp in L. lactis improved tolerance to heat and acid conditions in this species. Finally, the improvement of the L. lactis survival in milk medium thanks to Lo18 was highlighted, suggesting an interesting role of this sHsp. These findings suggest that the expression of a sHsp by a L. lactis strain results in greater resistance to stress, and, can consequently enhance the performances of industrial strains. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. A study on nuclear heat load tolerable for NET/TF coils cooled by internal flow of helium II

    International Nuclear Information System (INIS)

    Hofmann, A.

    1988-02-01

    NbTi cables cooled by internal flow of superfluid helium are considered an option for the design of NET/TF coils with about 11 T peak fields. Starting from an available winding cross section of 0.61x0.61 m 2 for a 8 MA turns coil made of a 16 kA conductor it is shown that sufficient hydraulic cross section can be provided within such cables to remove the expected thermal load resulting from nuclear heating with exponential decay from inboard to outboard side of the winding. The concept is a pancake type coil with 1.8 K helium fed-in the high field region of each pancake. The temperature distribution within such coils is calculated, and the local safety margin is determined from temperature and field. The calculation takes account of nuclear and a.c. heating, and of thermal conductance between the individual layers and the coil casing. It is shown that operation with 1.8 K inlet and about 3 K outlet temperature is possible. The electrical insulation with about 0.5 mm thickness proves to provide sufficient thermal insulation. No additional thermal shield is required between the coil casing and the winding package. Two different types of conductors are being considered: a) POLO type cable with quadratic cross section and a central circular coolant duct, and b) an LCT type cable with two conductors wound in hand. Both concepts with about 500 m length of the cooland channels are shown to meet the requirements resulting from a peak nuclear heat load of 0.3 mW/cm 3 in the inboard turns. The hydraulic diameters are sufficient to operate each coils with self-sustained fountain effect pumps. Even appreciably higher heat loads with up to 3 mW/cm 3 of nuclear heating can be tolerated for the POLO type cable when the hydraulic diameter is enlarged to its maximum of 17 mm. (orig.) [de

  2. Comparative analysis of the heat stable proteome of radicles of Medicago truncatula seeds during germination identifies late embryogenesis abundant proteins associated with desiccation tolerance

    NARCIS (Netherlands)

    Boudet, J.; Buitink, J.; Hoekstra, F.A.; Rogniaux, H.; Larré, C.; Satour, P.; Leprince, O.

    2006-01-01

    A proteomic analysis was performed on the heat stable protein fraction of imbibed radicles of Medicago truncatula seeds to investigate whether proteins can be identified that are specifically linked to desiccation tolerance (DT). Radicles were compared before and after emergence (2.8 mm long) in

  3. Insect cold tolerance and repair of chill-injury at fluctuating thermal regimes: Role of 70kDa heat shock protein expression

    Czech Academy of Sciences Publication Activity Database

    Tollarová-Borovanská, Michaela; Lalouette, L.; Košťál, Vladimír

    2009-01-01

    Roč. 30, č. 5 (2009), s. 312-319 ISSN 0143-2044 R&D Projects: GA ČR GA206/07/0269 Institutional research plan: CEZ:AV0Z50070508 Keywords : insect * cold tolerance * heat shock proteins Subject RIV: ED - Physiology Impact factor: 1.074, year: 2009

  4. QTLs and Potential Candidate Genes for Heat Stress Tolerance Identified from the Mapping Populations Specifically Segregating for Fv/Fm in Wheat

    Directory of Open Access Journals (Sweden)

    Dew Kumari Sharma

    2017-09-01

    Full Text Available Despite the fact that Fv/Fm (maximum quantum efficiency of photosystem II is the most widely used parameter for a rapid non-destructive measure of stress detection in plants, there are barely any studies on the genetic understanding of this trait under heat stress. Our aim was to identify quantitative trait locus (QTL and the potential candidate genes linked to Fv/Fm for improved photosynthesis under heat stress in wheat (Triticum aestivum L.. Three bi-parental F2 mapping populations were generated by crossing three heat tolerant male parents (origin: Afghanistan and Pakistan selected for high Fv/Fm with a common heat susceptible female parent (origin: Germany selected for lowest Fv/Fm out of a pool of 1274 wheat cultivars of diverse geographic origin. Parents together with 140 F2 individuals in each population were phenotyped by Fv/Fm under heat stress (40°C for 3 days around anthesis. The Fv/Fm decreased by 6.3% in the susceptible parent, 1–2.5% in the tolerant parents and intermediately 4–6% in the mapping populations indicating a clear segregation for the trait. The three populations were genotyped with 34,955 DArTseq and 27 simple sequence repeat markers, out of which ca. 1800 polymorphic markers mapped to 27 linkage groups covering all the 21 chromosomes with a total genome length of about 5000 cM. Inclusive composite interval mapping resulted in the identification of one significant and heat-stress driven QTL in each population on day 3 of the heat treatment, two of which were located on chromosome 3B and one on chromosome 1D. These QTLs explained about 13–35% of the phenotypic variation for Fv/Fm with an additive effect of 0.002–0.003 with the positive allele for Fv/Fm originating from the heat tolerant parents. Approximate physical localization of these three QTLs revealed the presence of 12 potential candidate genes having a direct role in photosynthesis and/or heat tolerance. Besides providing an insight into the genetic

  5. Antioxidant enzymatic activities and gene expression associated with heat tolerance in the stems and roots of two cucurbit species ("Cucurbita maxima" and "Cucurbita moschata") and their interspecific inbred line "Maxchata".

    Science.gov (United States)

    Ara, Neelam; Nakkanong, Korakot; Lv, Wenhui; Yang, Jinghua; Hu, Zhongyuan; Zhang, Mingfang

    2013-12-10

    The elucidation of heat tolerance mechanisms is required to combat the challenges of global warming. This study aimed to determine the antioxidant enzyme responses to heat stress, at the enzymatic activity and gene expression levels, and to investigate the antioxidative alterations associated with heat tolerance in the stems and roots of squashes using three genotypes differing in heat tolerance. Plants of heat-tolerant "C. moschata", thermolabile "C. maxima" and moderately heat-tolerant interspecific inbred line "Maxchata" genotypes were exposed to moderate (37 °C) and severe (42 °C) heat shocks. "C. moschata" exhibited comparatively little oxidative damage, with the lowest hydrogen peroxide (H2O2), superoxide (O2(-)) and malondialdehyde (MDA) contents in the roots compared to stems, followed by "Maxchata". The enzyme activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD) were found to be increased with heat stress in tolerant genotypes. The significant inductions of FeSOD, MnSOD, APX2, CAT1 and CAT3 isoforms in tolerant genotypes suggested their participation in heat tolerance. The differential isoform patterns of SOD, APX and CAT between stems and roots also indicated their tissue specificity. Furthermore, despite the sequence similarity of the studied antioxidant genes among "C. maxima" and "Maxchata", most of these genes were highly induced under heat stress in "Maxchata", which contributed to its heat tolerance. This phenomenon also indicated the involvement of other unknown genetic and/or epigenetic factors in controlling the expression of these antioxidant genes in squashes, which demands further exploration.

  6. Antioxidant Enzymatic Activities and Gene Expression Associated with Heat Tolerance in the Stems and Roots of Two Cucurbit Species (“Cucurbita maxima” and “Cucurbita moschata” and Their Interspecific Inbred Line “Maxchata”

    Directory of Open Access Journals (Sweden)

    Neelam Ara

    2013-12-01

    Full Text Available The elucidation of heat tolerance mechanisms is required to combat the challenges of global warming. This study aimed to determine the antioxidant enzyme responses to heat stress, at the enzymatic activity and gene expression levels, and to investigate the antioxidative alterations associated with heat tolerance in the stems and roots of squashes using three genotypes differing in heat tolerance. Plants of heat-tolerant “C. moschata”, thermolabile “C. maxima” and moderately heat-tolerant interspecific inbred line “Maxchata” genotypes were exposed to moderate (37 °C and severe (42 °C heat shocks. “C. moschata” exhibited comparatively little oxidative damage, with the lowest hydrogen peroxide (H2O2, superoxide (O2− and malondialdehyde (MDA contents in the roots compared to stems, followed by “Maxchata”. The enzyme activities of superoxide dismutase (SOD, ascorbate peroxidase (APX, catalase (CAT and peroxidase (POD were found to be increased with heat stress in tolerant genotypes. The significant inductions of FeSOD, MnSOD, APX2, CAT1 and CAT3 isoforms in tolerant genotypes suggested their participation in heat tolerance. The differential isoform patterns of SOD, APX and CAT between stems and roots also indicated their tissue specificity. Furthermore, despite the sequence similarity of the studied antioxidant genes among “C. maxima” and “Maxchata”, most of these genes were highly induced under heat stress in “Maxchata”, which contributed to its heat tolerance. This phenomenon also indicated the involvement of other unknown genetic and/or epigenetic factors in controlling the expression of these antioxidant genes in squashes, which demands further exploration.

  7. Antioxidant Enzymatic Activities and Gene Expression Associated with Heat Tolerance in the Stems and Roots of Two Cucurbit Species (“Cucurbita maxima” and “Cucurbita moschata”) and Their Interspecific Inbred Line “Maxchata”

    Science.gov (United States)

    Ara, Neelam; Nakkanong, Korakot; Lv, Wenhui; Yang, Jinghua; Hu, Zhongyuan; Zhang, Mingfang

    2013-01-01

    The elucidation of heat tolerance mechanisms is required to combat the challenges of global warming. This study aimed to determine the antioxidant enzyme responses to heat stress, at the enzymatic activity and gene expression levels, and to investigate the antioxidative alterations associated with heat tolerance in the stems and roots of squashes using three genotypes differing in heat tolerance. Plants of heat-tolerant “C. moschata”, thermolabile “C. maxima” and moderately heat-tolerant interspecific inbred line “Maxchata” genotypes were exposed to moderate (37 °C) and severe (42 °C) heat shocks. “C. moschata” exhibited comparatively little oxidative damage, with the lowest hydrogen peroxide (H2O2), superoxide (O2−) and malondialdehyde (MDA) contents in the roots compared to stems, followed by “Maxchata”. The enzyme activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD) were found to be increased with heat stress in tolerant genotypes. The significant inductions of FeSOD, MnSOD, APX2, CAT1 and CAT3 isoforms in tolerant genotypes suggested their participation in heat tolerance. The differential isoform patterns of SOD, APX and CAT between stems and roots also indicated their tissue specificity. Furthermore, despite the sequence similarity of the studied antioxidant genes among “C. maxima” and “Maxchata”, most of these genes were highly induced under heat stress in “Maxchata”, which contributed to its heat tolerance. This phenomenon also indicated the involvement of other unknown genetic and/or epigenetic factors in controlling the expression of these antioxidant genes in squashes, which demands further exploration. PMID:24336062

  8. Genetic dissection of drought and heat tolerance in chickpea through genome-wide and candidate gene-based association mapping approaches.

    Directory of Open Access Journals (Sweden)

    Mahendar Thudi

    Full Text Available To understand the genetic basis of tolerance to drought and heat stresses in chickpea, a comprehensive association mapping approach has been undertaken. Phenotypic data were generated on the reference set (300 accessions, including 211 mini-core collection accessions for drought tolerance related root traits, heat tolerance, yield and yield component traits from 1-7 seasons and 1-3 locations in India (Patancheru, Kanpur, Bangalore and three locations in Africa (Nairobi, Egerton in Kenya and Debre Zeit in Ethiopia. Diversity Array Technology (DArT markers equally distributed across chickpea genome were used to determine population structure and three sub-populations were identified using admixture model in STRUCTURE. The pairwise linkage disequilibrium (LD estimated using the squared-allele frequency correlations (r2; when r2<0.20 was found to decay rapidly with the genetic distance of 5 cM. For establishing marker-trait associations (MTAs, both genome-wide and candidate gene-sequencing based association mapping approaches were conducted using 1,872 markers (1,072 DArTs, 651 single nucleotide polymorphisms [SNPs], 113 gene-based SNPs and 36 simple sequence repeats [SSRs] and phenotyping data mentioned above employing mixed linear model (MLM analysis with optimum compression with P3D method and kinship matrix. As a result, 312 significant MTAs were identified and a maximum number of MTAs (70 was identified for 100-seed weight. A total of 18 SNPs from 5 genes (ERECTA, 11 SNPs; ASR, 4 SNPs; DREB, 1 SNP; CAP2 promoter, 1 SNP and AMDH, 1SNP were significantly associated with different traits. This study provides significant MTAs for drought and heat tolerance in chickpea that can be used, after validation, in molecular breeding for developing superior varieties with enhanced drought and heat tolerance.

  9. Production optimization of a heat-tolerant alkaline pectinase from Bacillus subtilis ZGL14 and its purification and characterization.

    Science.gov (United States)

    Yu, Ping; Zhang, Yishu; Gu, Donglu

    2017-09-03

    Alkaline pectinase has important applications in the pretreatment of waste water from food processing and in both the fabric and paper industries. In this study, a 2-level factorial design was used to screen significant factors that affect the activity of alkaline pectinase, and the response surface methodology (RSM) with a Box-Behnken design (BBD) was used to optimize their concentrations. Starch, peptone, KH 2 PO 4 and K 2 HPO 4 ·3H 2 O were found to significantly affect the activity of alkaline pectinase. Their optimal concentrations were as follows: 4.68% starch, 1.6% peptone, 0.26% KH 2 PO 4 and 0.68% K 2 HPO 4 ·3H 2 O. Under the above conditions, the activity of alkaline pectinase was significantly improved to 734.11 U/mL. Alkaline pectinase was purified to homogeneity with a recovery rate of 9.6% and a specific activity of 52372.52 U/mg. Its optimal temperature and pH were 50°C and 8.6, respectively. The purified enzyme showed strong thermo-stability and good alkali resistance. In addition, the activity of alkaline pectinase was improved in the presence of Mg 2+ . Cu 2+ , Mn 2+ , and Co 2+ significantly inhibited its activity. This study provides an important basis for the future development and use of a heat-tolerant alkaline pectinase from B. subtilis ZGL14.

  10. Exacerbation of rheumatoid arthritis following Helicobacter pylori eradication: disruption of established oral tolerance against heat shock protein?

    Science.gov (United States)

    Matsukawa, Yoshihiro; Asai, Yasukiyo; Kitamura, Noboru; Sawada, Shigemasa; Kurosaka, Hanzo

    2005-01-01

    A 62-year-old Japanese woman with RA received an eradication therapy against Helicobacter pylori in November 1999. Eight weeks later, successful eradication was confirmed by negative results for rapid urease test, pathologic findings, and a fall in anti-H. pylori IgG antibody titer. During the course, parameters for RA activity were exacerbated: C-reactive protein 1.1-4.2 mg/dL, rheumatoid arthritis precipitation antigen 2560-5120 dils., erythrocyte sedimentation rate 52-123 mm/h, and complements CH50 50 to over 60 U/mL. Lansbury index increased from 70% to 105%. Two more weeks later, the patient noticed right shoulder pain. She also complained of bilateral gonalgia two months later, and physical examination revealed increased fluid in the knee joints. Prednisolone was required to control the disease activity. The results of this case suggested that RA patients might experience a deleterious effect on the disease activity following H. pylori eradication possibly through disruption of the established oral tolerance against stress protein such as mycobacterial heat shock protein 65.

  11. Ensemble yield simulations: Using heat-tolerant and later-maturing varieties to adapt to climate warming.

    Directory of Open Access Journals (Sweden)

    Yi Zhang

    Full Text Available The use of modern crop varieties is a dominant method of obtaining high yields in crop production. Efforts to identify suitable varieties, with characteristics that would increase crop yield under future climate conditions, remain essential to developing sustainable agriculture and food security. This work aims to evaluate potential genotypic adaptations (i.e., using varieties with increased ability to produce desirable grain numbers under high temperatures and with enhanced thermal time requirements during the grain-filling period to cope with the negative impacts of climate change on maize yield. The contributions of different options were investigated at six sites in the North China Plain using the APSIM model and the outputs of 8 GCMs under RCP4.5 scenarios. It was found that without considering adaptation options, mean maize yield would decrease by 7~18% during 2010-2039 relative to 1976-2005. A large decrease in grain number relative to stabilized grain weight decreased maize yield under future climate scenarios. Using heat-tolerant varieties, maize yield could increase on average by 6% to 10%. Using later maturing varieties, e.g., enhanced thermal time requirements during the grain-filling period, maize yield could increase by 7% to 10%. The optimal adaptation options were site specific.

  12. An attempt to interpret a biochemical mechanism of C4 photosynthetic thermo-tolerance under sudden heat shock on detached leaf in elevated CO2 grown maize.

    Directory of Open Access Journals (Sweden)

    Mingnan Qu

    Full Text Available Detached leaves at top canopy structures always experience higher solar irradiance and leaf temperature under natural conditions. The ability of tolerance to high temperature represents thermotolerance potential of whole-plants, but was less of concern. In this study, we used a heat-tolerant (B76 and a heat-susceptible (B106 maize inbred line to assess the possible mitigation of sudden heat shock (SHS effects on photosynthesis (PN and C4 assimilation pathway by elevated [CO2]. Two maize lines were grown in field-based open top chambers (OTCs at ambient and elevated (+180 ppm [CO2]. Top-expanded leaves for 30 days after emergence were suddenly exposed to a 45°C SHS for 2 hours in midday during measurements. Analysis on thermostability of cellular membrane showed there was 20% greater electrolyte leakage in response to the SHS in B106 compared to B76, in agreement with prior studies. Elevated [CO2] protected PN from SHS in B76 but not B106. The responses of PN to SHS among the two lines and grown CO2 treatments were closely correlated with measured decreases of NADP-ME enzyme activity and also to its reduced transcript abundance. The SHS treatments induced starch depletion, the accumulation of hexoses and also disrupted the TCA cycle as well as the C4 assimilation pathway in the both lines. Elevated [CO2] reversed SHS effects on citrate and related TCA cycle metabolites in B106 but the effects of elevated [CO2] were small in B76. These findings suggested that heat stress tolerance is a complex trait, and it is difficult to identify biochemical, physiological or molecular markers that accurately and consistently predict heat stress tolerance.

  13. Heat treatment of egg white controls allergic symptoms and induces oral tolerance to ovalbumin in a murine model of food allergy.

    Science.gov (United States)

    Watanabe, Hiroko; Toda, Masako; Sekido, Haruko; Wellner, Anne; Fujii, Tomoyuki; Henle, Thomas; Hachimura, Satoshi; Nakajima-Adachi, Haruyo

    2014-02-01

    Heated foods often present low allergenicity, and have recently been used in specific oral immunotherapy for food allergies. However, the influence of heating on tolerogenicity of food allergens is not well elucidated. Here, we investigated biochemical, allergenic, and tolerogenic properties of heated egg white (EW) using a murine model of food allergy. Raw EWs were treated at 80°C for 15 min (80EW, mild heating condition), 100°C for 5 min (100EW, cooking condition), or 121°C for 40 min (121EW, retort pouch condition), and freeze-dried. A transgenic OVA23-3 mice model expressing T-cell receptor specific for ovalbumin (OVA, a major EW allergen) induced Th2 cells and IgE production, and presented intestinal inflammation when fed untreated EW diet. 80EW-fed mice presented only moderate inflammation but high Th2 responses. 100EW-fed mice did not present inflammation but induced tolerance as seen in reduced T-cell responses and IgE levels. 100EW demonstrated higher digestive stability and slower absorption in intestine, compared with untreated EW and 80EW. 121EW was strongly aggregated, was not absorbed well, and developed Th1 responses without tolerance induction. OVA in EW treated only under a particular heat condition (e.g. 100°C for 5 min) lost allergenicity, but possessed tolerogenicity. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Metallothionein and Hsp70 trade-off against one another in Daphnia magna cross-tolerance to cadmium and heat stress

    Energy Technology Data Exchange (ETDEWEB)

    Haap, Timo, E-mail: timo.haap@gmx.de; Schwarz, Simon; Köhler, Heinz-R.

    2016-01-15

    Highlights: • Cadmium acclimation of two Daphnia magna clones which differed in Cd sensitivity and Hsp70 levels. • Two distinct metal-handling strategies regarding Hsp70 and MT expression were observed. • High Hsp70 levels did not confer an increase in Cd and heat stress tolerance. • Our results indicate a trade-off between Hsp70 and MT. - Abstract: The association between the insensitivity of adapted ecotypes of invertebrates to environmental stress, such as heavy metal pollution, and overall low Hsp levels characterizing these organisms has been attracting attention in various studies. The present study seeks to induce and examine this phenomenon in Daphnia magna by multigenerational acclimation to cadmium in a controlled laboratory setting. In this experiment, interclonal variation was examined: two clones of D. magna that have previously been characterized to diverge regarding their cadmium resistance and levels of the stress protein Hsp70, were continuously exposed to a sublethal concentration of Cd over four generations to study the effects of acclimation on Hsp70, metallothionein (MT), reproduction and cross-tolerance to heat stress. The two clones differed in all the measured parameters in a characteristic way, clone T displaying Cd and heat resistance, lower Hsp70 levels and offspring numbers on the one hand and higher MT expression on the other hand, clone S the opposite for all these parameters. We observed only slight acclimation-induced changes in constitutive Hsp70 levels and reproductive output. The differences in MT expression between clones as well as between acclimated organisms and controls give evidence for MT accounting for the higher Cd tolerance of clone T. Overall high Hsp70 levels of clone S did not confer cross tolerance to heat stress, contrary to common expectations. Our results suggest a trade-off between the efforts to limit the proteotoxic symptoms of Cd toxicity by Hsp70 induction and those to sequester and detoxify Cd by

  15. Effects of heat, cold, acid and bile salt adaptations on the stress tolerance and protein expression of kefir-isolated probiotic Lactobacillus kefiranofaciens M1.

    Science.gov (United States)

    Chen, Ming-Ju; Tang, Hsin-Yu; Chiang, Ming-Lun

    2017-09-01

    Lactobacillus kefiranofaciens M1 is a probiotic strain isolated from Taiwanese kefir grains. The present study evaluated the effects of heat, cold, acid and bile salt adaptations on the stress tolerance of L. kefiranofaciens M1. The regulation of protein expression of L. kefiranofaciens M1 under these adaptation conditions was also investigated. The results showed that adaptation of L. kefiranofaciens M1 to heat, cold, acid and bile salts induced homologous tolerance and cross-protection against heterologous challenge. The extent of induced tolerance varied depending on the type and condition of stress. Proteomic analysis revealed that 27 proteins exhibited differences in expression between non-adapted and stress-adapted L. kefiranofaciens M1 cells. Among these proteins, three proteins involved in carbohydrate metabolism (triosephosphate isomerase, enolase and NAD-dependent glycerol-3-phosphate dehydrogenase), two proteins involved in pH homeostasis (ATP synthase subunits AtpA and AtpB), two stress response proteins (chaperones DnaK and GroEL) and one translation-related protein (30S ribosomal protein S2) were up-regulated by three of the four adaptation treatments examined. The increased synthesis of these stress proteins might play a critical protective role in the cellular defense against heat, cold, acid and bile salt stresses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Quality control of Photosystem II: the mechanisms for avoidance and tolerance of light and heat stresses are closely linked to membrane fluidity of the thylakoids

    Directory of Open Access Journals (Sweden)

    Yasusi Yamamoto

    2016-08-01

    Full Text Available When oxygenic photosynthetic organisms are exposed to excessive light and/or heat, Photosystem II is damaged and electron transport is blocked. In these events, reactive oxygen species, endogenous radicals and lipid peroxidation products generated by photochemical reaction and/or heat cause the damage. Regarding light stress, plants first dissipate excessive light energy captured by light-harvesting chlorophyll protein complexes as heat to avoid the hazards, but once light stress is unavoidable, they tolerate the stress by concentrating damage in a particular protein in photosystem II, i.e. the reaction-center binding D1 protein of Photosystem II. The damaged D1 is removed by specific proteases and replaced with a new copy produced through de novo synthesis (reversible photoinhibition. When light intensity becomes extremely high, irreversible aggregation of D1 occurs and thereby D1 turnover is prevented. Once the aggregated products accumulate in Photosystem II complexes, removal of them by proteases is difficult, and irreversible inhibition of Photosystem II takes place (irreversible photoinhibition. Important is that various aspects of both the reversible and irreversible photoinhibition are highly dependent on the membrane fluidity of the thylakoids. Heat stress-induced inactivation of photosystem II is an irreversible process, which may be also affected by the fluidity of the thylakoid membranes. Here I describe why the membrane fluidity is a key to regulate the avoidance and tolerance of Photosystem II on environmental stresses.

  17. Crafting tolerance

    DEFF Research Database (Denmark)

    Kirchner, Antje; Freitag, Markus; Rapp, Carolin

    2011-01-01

    Ongoing changes in social structures, orientation, and value systems confront us with the growing necessity to address and understand transforming patterns of tolerance as well as specific aspects, such as social tolerance. Based on hierarchical analyses of the latest World Values Survey (2005...... results show that specific institutional qualities, which reduce status anxiety, such as inclusiveness, universality, and fairness, prevail over traditional socio-economic, societal, cultural, and democratic explanations....

  18. Co-overexpression of two Heat Shock Factors results in enhanced seed longevity and in synergistic effects on seedling tolerance to severe dehydration and oxidative stress.

    Science.gov (United States)

    Personat, José-María; Tejedor-Cano, Javier; Prieto-Dapena, Pilar; Almoguera, Concepción; Jordano, Juan

    2014-03-04

    We have previously reported that the seed-specific overexpression of sunflower (Helianthus annuus L.) Heat Shock Factor A9 (HaHSFA9) enhanced seed longevity in transgenic tobacco (Nicotiana tabacum L.). In addition, the overexpression of HaHSFA9 in vegetative organs conferred tolerance to drastic levels of dehydration and oxidative stress. Here we found that the combined overexpression of sunflower Heat Shock Factor A4a (HaHSFA4a) and HaHSFA9 enhanced all the previously reported phenotypes described for the overexpression of HaHSFA9 alone. The improved phenotypes occurred in coincidence with only subtle changes in the accumulation of small Heat Shock Proteins (sHSP) that are encoded by genes activated by HaHSFA9. The single overexpression of HaHSFA4a in vegetative organs (which lack endogenous HSFA9 proteins) did not induce sHSP accumulation under control growth conditions; neither it conferred thermotolerance. The overexpression of HaHSFA4a alone also failed to induce tolerance to severe abiotic stress. Thus, a synergistic functional effect of both factors was evident in seedlings. Our study revealed that HaHSFA4a requires HaHSFA9 for in planta function. Our results strongly support the involvement of HaHSFA4a and HaHSFA9 in transcriptional co-activation of a genetic program of longevity and desiccation tolerance in sunflower seeds. These results would also have potential application for improving seed longevity and tolerance to severe stress in vegetative organs.

  19. Ectopic expression of TaOEP16-2-5B, a wheat plastid outer envelope protein gene, enhances heat and drought stress tolerance in transgenic Arabidopsis plants.

    Science.gov (United States)

    Zang, Xinshan; Geng, Xiaoli; Liu, Kelu; Wang, Fei; Liu, Zhenshan; Zhang, Liyuan; Zhao, Yue; Tian, Xuejun; Hu, Zhaorong; Yao, Yingyin; Ni, Zhongfu; Xin, Mingming; Sun, Qixin; Peng, Huiru

    2017-05-01

    Abiotic stresses, such as heat and drought, are major environmental factors restricting crop productivity and quality worldwide. A plastid outer envelope protein gene, TaOEP16-2, was identified from our previous transcriptome analysis [1,2]. In this study, the isolation and functional characterization of the TaOEP16-2 gene was reported. Three homoeologous sequences of TaOEP16-2 were isolated from hexaploid wheat, which were localized on the chromosomes 5A, 5B and 5D, respectively. These three homoeologues exhibited different expression patterns under heat stress conditions, TaOEP16-2-5B was the dominant one, and TaOEP16-2-5B was selected for further analysis. Compared with wild type (WT) plants, transgenic Arabidopsis plants overexpressing the TaOEP16-2-5B gene exhibited enhanced tolerance to heat stress, which was supported by improved survival rate, strengthened cell membrane stability and increased sucrose content. It was also found that TaOEP16-2 was induced by drought stress and involved in drought stress tolerance. TaOEP16-2-5B has the same function in ABA-controlled seed germination as AtOEP16-2. Our results suggest that TaOEP16-2-5B plays an important role in heat and drought stress tolerance, and could be utilized in transgenic breeding of wheat and other crop plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Dietary supplementation of curcumin augments heat stress tolerance through upregulation of nrf-2-mediated antioxidative enzymes and hsps in Puntius sophore.

    Science.gov (United States)

    Mahanty, Arabinda; Mohanty, Sasmita; Mohanty, Bimal P

    2017-08-01

    Heat stress is one of the major environmental concerns in global warming regime and rising temperature has resulted in mass mortalities of animals including fishes. Therefore, strategies for high temperature stress tolerance and ameliorating the effects of heat stress are being looked for. In an earlier study, we reported that Nrf-2 (nuclear factor E2-related factor 2) mediated upregulation of antioxidative enzymes and heat shock proteins (Hsps) provide survivability to fish under heat stress. In this study, we have evaluated the ameliorative potential of dietary curcumin, a potential Nrf-2 inducer in heat stressed cyprinid Puntius sophore. Fishes were fed with diet supplemented with 0.5, 1.0, and 1.5% curcumin at the rate 2% of body weight daily in three separate groups (n = 40 in each group) for 60 days. Fishes fed with basal diet (without curcumin) served as the control (n = 40). Critical thermal maxima (CTmax) was determined for all the groups (n = 10, in duplicates) after the feeding trial. Significant increase in the CTmax was observed in the group fed with 1.5% curcumin- supplemented fishes whereas it remained similar in groups fed with 0.5%, and 1% curcumin-supplemented diet, as compared to control. To understand the molecular mechanism of elevated thermotolerance in the 1.5% curcumin supplemented group, fishes were given a sub-lethal heat shock treatment (36 °C) for 6 h and expression analysis of nrf-2, keap-1, sod, catalase, gpx, and hsp27, hsp60, hsp70, hsp90, and hsp110 was carried out using RT-PCR. In the gill, expression of nrf-2, sod, catalase, gpx, and hsp60, hsp70, hsp90, and hsp110 was found to be elevated in the 1.5% curcumin-fed heat-shocked group compared to control and the basal diet-fed, heat-shocked fishes. Similarly, in the liver, upregulation in expression of nrf-2, sod, catalase, and hsp70 and hsp110 was observed in 1.5% curcumin supplemented and heat shocked group. Thus, this study showed that supplementation of curcumin

  1. Survey of Thermal-Fluids Evaluation and Confirmatory Experimental Validation Requirements of Accident Tolerant Cladding Concepts with Focus on Boiling Heat Transfer Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Nicholas R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wysocki, Aaron J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Terrani, Kurt A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ali, Amir [Univ. of New Mexico, Albuquerque, NM (United States); Liu, Maolong [Univ. of New Mexico, Albuquerque, NM (United States); Blandford, Edward [Univ. of New Mexico, Albuquerque, NM (United States)

    2016-06-01

    The U.S. Department of Energy Office of Nuclear Energy (DOE-NE) Advanced Fuels Campaign (AFC) is working closely with the nuclear industry to develop fuel and cladding candidates with potentially enhanced accident tolerance, also known as accident tolerant fuel (ATF). Thermal-fluids characteristics are a vital element of a holistic engineering evaluation of ATF concepts. One vital characteristic related to boiling heat transfer is the critical heat flux (CHF). CHF plays a vital role in determining safety margins during normal operation and also in the progression of potential transient or accident scenarios. This deliverable is a scoping survey of thermal-fluids evaluation and confirmatory experimental validation requirements of accident tolerant cladding concepts with a focus on boiling heat transfer characteristics. The key takeaway messages of this report are: 1. CHF prediction accuracy is important and the correlations may have significant uncertainty. 2. Surface conditions are important factors for CHF, primarily the wettability that is characterized by contact angle. Smaller contact angle indicates greater wettability, which increases the CHF. Surface roughness also impacts wettability. Results in the literature for pool boiling experiments indicate changes in CHF by up to 60% for several ATF cladding candidates. 3. The measured wettability of FeCrAl (i.e., contact angle and roughness) indicates that CHF should be investigated further through pool boiling and flow boiling experiments. 4. Initial measurements of static advancing contact angle and surface roughness indicate that FeCrAl is expected to have a higher CHF than Zircaloy. The measured contact angle of different FeCrAl alloy samples depends on oxide layer thickness and composition. The static advancing contact angle tends to decrease as the oxide layer thickness increases.

  2. High levels of sarcospan are well tolerated and act as a sarcolemmal stabilizer to address skeletal muscle and pulmonary dysfunction in DMD.

    Science.gov (United States)

    Gibbs, Elizabeth M; Marshall, Jamie L; Ma, Eva; Nguyen, Thien M; Hong, Grace; Lam, Jessica S; Spencer, Melissa J; Crosbie-Watson, Rachelle H

    2016-12-15

    Duchenne muscular dystrophy (DMD) is a genetic disorder that causes progressive muscle weakness, ultimately leading to early mortality in affected teenagers and young adults. Previous work from our lab has shown that a small transmembrane protein called sarcospan (SSPN) can enhance the recruitment of adhesion complex proteins to the cell surface. When human SSPN is expressed at three-fold levels in mdx mice, this increase in adhesion complex abundance improves muscle membrane stability, preventing many of the histopathological changes associated with DMD. However, expressing higher levels of human SSPN (ten-fold transgenic expression) causes a severe degenerative muscle phenotype in wild-type mice. Since SSPN-mediated stabilization of the sarcolemma represents a promising therapeutic strategy in DMD, it is important to determine whether SSPN can be introduced at high levels without toxicity. Here, we show that mouse SSPN (mSSPN) can be overexpressed at 30-fold levels in wild-type mice with no deleterious effects. In mdx mice, mSSPN overexpression improves dystrophic pathology and sarcolemmal stability. We show that these mice exhibit increased resistance to eccentric contraction-induced damage and reduced fatigue following exercise. mSSPN overexpression improved pulmonary function and reduced dystrophic histopathology in the diaphragm. Together, these results demonstrate that SSPN overexpression is well tolerated in mdx mice and improves sarcolemma defects that underlie skeletal muscle and pulmonary dysfunction in DMD. © The Author 2016. Published by Oxford University Press.

  3. Heat

    CERN Document Server

    Lawrence, Ellen

    2016-01-01

    Is it possible to make heat by rubbing your hands together? Why does an ice cube melt when you hold it? In this title, students will conduct experiments to help them understand what heat is. Kids will also investigate concepts such as which materials are good at conducting heat and which are the best insulators. Using everyday items that can easily be found around the house, students will transform into scientists as they carry out step-by-step experiments to answer interesting questions. Along the way, children will pick up important scientific skills. Heat includes seven experiments with detailed, age-appropriate instructions, surprising facts and background information, a "conclusions" section to pull all the concepts in the book together, and a glossary of science words. Colorful, dynamic designs and images truly put the FUN into FUN-damental Experiments.

  4. Heat Acclimatization Protects the Left Ventricle from Increased Diastolic Chamber Stiffness Immediately after Coronary Artery Bypass Surgery: A Lesson from 30 Years of Studies on Heat Acclimation Mediated Cross Tolerance

    Directory of Open Access Journals (Sweden)

    Arthur Pollak

    2017-12-01

    Full Text Available During the period of 1986–1997 the first 4 publications on the mechanical and metabolic properties of heat acclimated rat's heart were published. The outcome of these studies implied that heat acclimation, sedentary as well as combined with exercise training, confers long lasting protection against ischemic/reperfusion insult. These results promoted a clinical study on patients with coronary artery disease scheduled for elective coronary artery bypass operations aiming to elucidate whether exploitation of environmental stress can be translated into human benefits by improving physiological recovery. During the 1998 study, immediate-post operative chamber stiffness was assessed in patients acclimatized to heat and low intensity training in the desert (spring in the Dead Sea, 17–33°C vs. patients in colder weather (spring in non-desert areas, 6–19°C via echocardiogram acquisition simultaneous with left atrial pressure measurement during fast intravascular fluid bolus administration. We showed that patients undergoing “heat acclimatization combined with exercise training” were less susceptible to ischemic injury, therefore expressing less diastolic dysfunction after cardiopulmonary bypass compared to non-acclimatized patients. This was the first clinical translational study on cardiac patients, while exploiting environmental harsh conditions for human benefits. The original experimental data are described and discussed in view of the past as well as the present knowledge of the protective mechanisms induced by Heat Acclimation Mediated Cross-tolerance.

  5. Field tests on human tolerance to (LNG) fire radiant heat exposure, and attenuation effects of clothing and other objects

    International Nuclear Information System (INIS)

    Raj, Phani K.

    2008-01-01

    A series of field tests exposing mannequins clothed with civilian clothing to a 3 m x 3 m square liquefied natural gas (LNG) pool fire was conducted. Both single layer clothing and double layer clothing were used. The radiant heat flux incident outside the clothing and incident on the skin covered by clothing were measured using wide-angle radiometers, for durations of 100-200 s (per test). The levels of heat flux incident on the clothing were close to 5 kW/m 2 . The magnitude of the radiant heat attenuation factor (AF) across the thickness was determined. AF varies between 2 and higher for cotton and polyester clothing (thickness 0.286-1.347 mm); AF value of 6 was measured for 1.347 mm thickness. Single sheet newspaper held about 5 cm in front of mannequins and exposed to incident flux of 5 kW/m 2 resulted in AF of 5, and AF of 8 with double sheets. AF decreases linearly with increasing heat flux values and linearly increases with thickness. The author exposed himself, in normal civilian clothing (of full sleeve cotton/polyester shirt and jean pants), to radiant heat from a LNG fire. The exposure was for several tens of seconds to heat flux levels ranging from 3.5 kW/m 2 to 5 + kW/m 2 (exposure times from 25 s to 97 s at average heat flux values in the 4 kW/m 2 and 5 kW/m 2 range). Occasionally, he was exposed to (as high as) 7 kW/m 2 for durations of several seconds. He did not suffer any unbearable or even severe pain nor did he experience blisters or burns or any other injury on the unprotected skin of his body. The incident heat fluxes on the author were measured by a hand-held radiometer (with digital display) as well as by strapped on wide-angle radiometers connected to a computer. He could withstand the US regulatory criterion of 5 kW/m 2 (for 30 s) without suffering any damage or burns. Temperature measured on author's skin covered by clothing did not rise above the normal body temperature even after 200 s of exposure to 4 kW/m 2 average heat flux

  6. Overexpression of small heat shock protein LimHSP16.45 in Arabidopsis enhances tolerance to abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Changjun Mu

    Full Text Available Small heat shock proteins (smHSPs play important and extensive roles in plant defenses against abiotic stresses. We cloned a gene for a smHSP from the David Lily (Lilium davidii (E. H. Wilson Raffill var. Willmottiae, which we named LimHSP16.45 based on its protein molecular weight. Its expression was induced by many kinds of abiotic stresses in both the lily and transgenic plants of Arabidopsis. Heterologous expression enhanced cell viability of the latter under high temperatures, high salt, and oxidative stress, and heat shock granules (HSGs formed under heat or salinity treatment. Assays of enzymes showed that LimHSP16.45 overexpression was related to greater activity by superoxide dismutase and catalase in transgenic lines. Therefore, we conclude that heterologous expression can protect plants against abiotic stresses by preventing irreversible protein aggregation, and by scavenging cellular reactive oxygen species.

  7. Small heat-shock proteins and leaf cooling capacity account for the unusual heat tolerance of the central spike leaves in Agave tequilana var. Weber.

    Science.gov (United States)

    Luján, Rosario; Lledías, Fernando; Martínez, Luz María; Barreto, Rita; Cassab, Gladys I; Nieto-Sotelo, Jorge

    2009-12-01

    Agaves are perennial crassulacean acid metabolism (CAM) plants distributed in tropical and subtropical arid environments, features that are attractive for studying the heat-shock response. In agaves, the stress response can be analysed easily during leaf development, as they form a spirally shaped rosette, having the meristem surrounded by folded leaves in the centre (spike) and the unfolded and more mature leaves in the periphery. Here, we report that the spike of Agave tequilana is the most thermotolerant part of the rosette withstanding shocks of up to 55 degrees C. This finding was inconsistent with the patterns of heat-shock protein (Hsp) gene expression, as maximal accumulation of Hsp transcripts was at 44 degrees C in all sectors (spike, inner, middle and outer). However, levels of small HSP (sHSP)-CI and sHSP-CII proteins were conspicuously higher in spike leaves at all temperatures correlating with their thermotolerance. In addition, spike leaves showed a higher stomatal density and abated more efficiently their temperature several degrees below that of air. We propose that the greater capacity for leaf cooling during the day in response to heat stress, and the elevated levels of sHSPs, constitute part of a set of strategies that protect the SAM and folded leaves of A. tequilana from high temperatures.

  8. Effects of CO2 on the tolerance of photosynthesis to heat stress can be affected by photosynthetic pathway and nitrogen.

    Science.gov (United States)

    Wang, Dan; Heckathorn, Scott A; Hamilton, E William; Frantz, Jonathan

    2014-01-01

    Determining effects of elevated CO2 and N on photosynthetic thermotolerance is critical for predicting plant responses to global warming. We grew Hordeum vulgare (barley, C3) and Zea mays (corn, C4) at current or elevated CO2 (370, 700 ppm) and limiting or optimal soil N (0.5, 7.5 mmol/L). We assessed thermotolerance of net photosynthesis (Pn), photosystem II efficiency in the light (Fv'/Fm'), photochemical quenching (qp), carboxylation efficiency (CE), and content of rubisco activase and major heat-shock proteins (HSPs). For barley, elevated CO2 had no effect on Pn, qp, and CE at both high and low N and only a positive effect on Fv'/Fm' at high N. However, for corn, Pn, Fv'/Fm', qp, and CE were decreased substantially by elevated CO2 under high and low N, with greater decreases at high N for all but qp. The negative effects of high CO2 during heat stress on photosynthesis were correlated with rubisco activase and HSPs content, which decreased with heat stress, especially for low-N corn. These results indicate that stimulatory effects of elevated CO2 at normal temperatures on photosynthesis and growth (only found for high-N barley) may be partly offset by neutral or negative effects during heat stress, especially for C4 species. Thus, CO2 and N effects on photosynthetic thermotolerance may contribute to changes in plant productivity, distribution, and diversity in future.

  9. Quantitative trait loci mapping of heat tolerance in broccoli (Brassica oleracea var. italica) using genotyping-by-sequencing

    Science.gov (United States)

    Predicted rising global temperatures due to climate change have generated a demand for crops that are resistant to yield and quality losses from heat stress. Broccoli (Brassica oleracea var. italica) is a cool weather crop with high temperatures during production decreasing both head quality and yie...

  10. Breed-specific ancestry studies and genome-wide association analysis highlight an association between the MYH9 gene and heat tolerance in Alaskan sprint racing sled dogs.

    Science.gov (United States)

    Huson, Heather J; vonHoldt, Bridgett M; Rimbault, Maud; Byers, Alexandra M; Runstadler, Jonathan A; Parker, Heidi G; Ostrander, Elaine A

    2012-02-01

    Alaskan sled dogs are a genetically distinct population shaped by generations of selective interbreeding with purebred dogs to create a group of high-performance athletes. As a result of selective breeding strategies, sled dogs present a unique opportunity to employ admixture-mapping techniques to investigate how breed composition and trait selection impact genomic structure. We used admixture mapping to investigate genetic ancestry across the genomes of two classes of sled dogs, sprint and long-distance racers, and combined that with genome-wide association studies (GWAS) to identify regions that correlate with performance-enhancing traits. The sled dog genome is enhanced by differential contributions from four non-admixed breeds (Alaskan Malamute, Siberian Husky, German Shorthaired Pointer, and Borzoi). A principal components analysis (PCA) of 115,000 genome-wide SNPs clearly resolved the sprint and distance populations as distinct genetic groups, with longer blocks of linkage disequilibrium (LD) observed in the distance versus sprint dogs (7.5-10 and 2.5-3.75 kb, respectively). Furthermore, we identified eight regions with the genomic signal from either a selective sweep or an association analysis, corroborated by an excess of ancestry when comparing sprint and distance dogs. A comparison of elite and poor-performing sled dogs identified a single region significantly associated with heat tolerance. Within the region we identified seven SNPs within the myosin heavy chain 9 gene (MYH9) that were significantly associated with heat tolerance in sprint dogs, two of which correspond to conserved promoter and enhancer regions in the human ortholog.

  11. Adaptation to high temperature mitigates the impact of water deficit during combined heat and drought stress in C3 sunflower and C4 maize varieties with contrasting drought tolerance.

    Science.gov (United States)

    Killi, Dilek; Bussotti, Filippo; Raschi, Antonio; Haworth, Matthew

    2017-02-01

    Heat and drought stress frequently occur together, however, their impact on plant growth and photosynthesis (P N ) is unclear. The frequency, duration and severity of heat and drought stress events are predicted to increase in the future, having severe implications for agricultural productivity and food security. To assess the impact on plant gas exchange, physiology and morphology we grew drought tolerant and sensitive varieties of C3 sunflower (Helianthus annuus) and C4 maize (Zea mays) under conditions of elevated temperature for 4 weeks prior to the imposition of water deficit. The negative impact of temperature on P N was most apparent in sunflower. The drought tolerant sunflower retained ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) activity under heat stress to a greater extent than its drought sensitive counterpart. Maize exhibited no varietal difference in response to increased temperature. In contrast to previous studies, where a sudden rise in temperature induced an increase in stomatal conductance (G s ), we observed no change or a reduction in G s with elevated temperature, which alongside lower leaf area mitigated the impact of drought at the higher temperature. The drought tolerant sunflower and maize varieties exhibited greater investment in root-systems, allowing greater uptake of the available soil water. Elevated temperatures associated with heat-waves will have profound negative impacts on crop growth in both sunflower and maize, but the deleterious effect on P N was less apparent in the drought tolerant sunflower and both maize varieties. As C4 plants generally exhibit water use efficiency (WUE) and resistance to heat stress, selection on the basis of tolerance to heat and drought stress would be more beneficial to the yields of C3 crops cultivated in drought prone semi-arid regions. © 2016 Scandinavian Plant Physiology Society.

  12. Relationship between the heat tolerance of photosynthesis and the thermal stability of rubisco activase in plants from contrasting thermal environments.

    Science.gov (United States)

    Salvucci, Michael E; Crafts-Brandner, Steven J

    2004-04-01

    Inhibition of net photosynthesis (Pn) by moderate heat stress has been attributed to an inability of Rubisco activase to maintain Rubisco in an active form. To examine this proposal, the temperature response of Pn, Rubisco activation, chlorophyll fluorescence, and the activities of Rubisco and Rubisco activase were examined in species from contrasting environments. The temperature optimum of Rubisco activation was 10 degrees C higher in the creosote bush (Larrea tridentata) compared with the Antarctic hairgrass (Deschampsia antarctica), resembling the temperature response of Pn. Pn increased markedly with increasing internal CO(2) concentration in Antarctic hairgrass and creosote bush plants subjected to moderate heat stress even under nonphotorespiratory conditions. Nonphotochemical quenching of chlorophyll fluorescence, the effective quantum yield of photochemical energy conversion (DeltaF/F(m)') and the maximum yield of PSII (F(v)/F(m)) were more sensitive to temperature in Antarctic hairgrass and two other species endemic to cold regions (i.e. Lysipomia pumila and spinach [Spinacea oleracea]) compared with creosote bush and three species (i.e. jojoba [Simmondsia chinensis], tobacco [Nicotiana tabacum], and cotton [Gossypium hirsutum]) from warm regions. The temperature response of activity and the rate of catalytic inactivation of Rubisco from creosote bush and Antarctic hairgrass were similar, whereas the optimum for ATP hydrolysis and Rubisco activation by recombinant creosote bush, cotton, and tobacco activase was 8 degrees C to 10 degrees C higher than for Antarctic hairgrass and spinach activase. These results support a role for activase in limiting photosynthesis at high temperature.

  13. SUMO-Dependent Synergism Involving Heat Shock Transcription Factors with Functions Linked to Seed Longevity and Desiccation Tolerance

    Directory of Open Access Journals (Sweden)

    Raúl Carranco

    2017-06-01

    Full Text Available A transcriptional synergism between HaHSFA9 (A9 and HaHSFA4a (A4a contributes to determining longevity and desiccation tolerance of sunflower (Helianthus annuus, L. seeds. Potential lysine SUMOylation sites were identified in A9 and A4a and mutated to arginine. We show that A9 is SUMOylated in planta at K38. Although we did not directly detect SUMOylated A4a in planta, we provide indirect evidence from transient expression experiments indicating that A4a is SUMOylated at K172. Different combinations of wild type and SUMOylation site mutants of A9 and A4a were analyzed by transient expression in sunflower embryos and leaves. Although most of the precedents in literature link SUMOylation with repression, the A9 and A4a synergism was fully abolished when the mutant forms for both factors were combined. However, the combination of mutant forms of A9 and A4a did not affect the nuclear retention of A4a by A9; therefore, the analyzed mutations would affect the synergism after the mutual interaction and nuclear co-localization of A9 and A4a. Our results suggest a role for HSF SUMOylation during late, zygotic, embryogenesis. The SUMOylation of A9 (or A4a would allow a crucial, synergic, transcriptional effect that occurs in maturing sunflower seeds.

  14. Tradeoffs to Thermal Acclimation: Energetics and Reproduction of a Reef Coral with Heat Tolerant Symbiodinium Type-D

    Directory of Open Access Journals (Sweden)

    Alison M. Jones

    2011-01-01

    Full Text Available The photo-physiological characteristics of thermo-tolerant Symbiodinium types have been postulated to have negative effects on the energetics of the reef corals by reducing fitness. To investigate this, two key and inextricably coupled indicators of fitness, lipids and reproduction, were monitored in colonies of the broadcast-spawning coral Acropora millepora over a two-year period that included a natural bleaching event. In the absence of bleaching ITS1-type clade D predominant colonies had 26% lower stored lipids compared to C2 colonies. At spawning time, this correlated with 28% smaller eggs in type-D colonies. This energetic disparity is expected to have reduced larval duration and settlement-competency periods in type-D compared to type-C2 colonies. More importantly, irrespective of the effect of genotype, the fitness of all corals was adversely affected by the stress of the bleaching event which reduced prespawning lipids by 60% and halved the number of eggs compared to the previous year. Our results extend work that has shown that direct temperature stress and symbiont change are likely to work in concert on corals by demonstrating that the lipids and reproduction of the reef building corals on tropical reefs are likely to be impaired by these processes as our climate warms.

  15. Opening Address

    Science.gov (United States)

    Garbers, C. F.

    1987-09-01

    Ladies and gentlemen, it is indeed a great privilege and pleasure for me to present the opening address at this, the 17th International Congress on High Speed Photograpy and Photonics. Before turning to the business of the Congress, I would like to briefly introduce you to South Africa: its scientific past and its research challenges for the future.

  16. PRESIDENTIAL ADDRESS

    African Journals Online (AJOL)

    Your Excellency. Honoured Guests. Members of the Association. It is my duty and pleasure to thank H.E. Lij. Endalkatchew Makonnen for the fine address with which he has opened this First National Conference of the EAEA. He has pointedly reminded us that though. Engineers and Architects play a key role, develop-.

  17. Multiple heat priming enhances thermo-tolerance to a later high temperature stress via improving subcellular antioxidant activities in wheat seedlings.

    Science.gov (United States)

    Wang, Xiao; Cai, Jian; Liu, Fulai; Dai, Tingbo; Cao, Weixing; Wollenweber, Bernd; Jiang, Dong

    2014-01-01

    Seedlings of winter wheat (Triticum aestivum L.) were firstly twice heat-primed at 32/24 °C, and subsequently subjected to a more severe high temperature stress at 35/27 °C. The later high temperature stress significantly decreased plant biomass and leaf total soluble sugars concentration. However, plants experienced priming (PH) up-regulated the Rubisco activase B encoding gene RcaB, which was in accordance with the higher photosynthesis rate in relation to the non-primed plants (NH) under the later high temperature stress. In relation to NH, the major chlorophyll a/b-binding protein gene Cab was down-regulated in PH plants, implying a reduction of the light absorption to protect the photosystem II from excitation energy under high temperature stress. At the same time, under the later high temperature stress PH plants showed significantly higher actual photochemical efficiency, indicating an improvement of light use efficiency due to the priming pre-treatment. Under the later high temperature stress, PH could be maintained a better redox homeostasis than NH, as exemplified by the higher activities of superoxide dismutase (SOD) in chloroplasts and glutathione reductase (GR), and of peroxidase (POD) in mitochondria, which contributed to the lower superoxide radical production rate and malondialdehyde concentration in both chloroplasts and mitochondria. The improved antioxidant capacity in chloroplasts and mitochondria was related to the up-regulated expressions of Cu/Zn-SOD, Mn-SOD and GR in PH. Collectively, heat priming effectively improved thermo-tolerance of wheat seedlings subjected to a later high temperature stress, which could be largely ascribed to the enhanced anti-oxidation at the subcellular level. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  18. Opening address

    International Nuclear Information System (INIS)

    Ianko, L.

    1993-01-01

    This short talk was the opening remarks to the attendees at this conference, presented by the Scientific Secretary, IWG-LMNPP, of the IAEA. This meeting is an effort to aid research on problems related to the general area of nuclear plant aging and life management. In particular it addresses fracture properties of reactor materials and components, both as installed, and at end of service condition. A major concern is relating measurements made on laboratory samples to properties displayed by actual reactor components

  19. Convocation address.

    Science.gov (United States)

    Zakaria, R

    1996-07-01

    By means of this graduation address at the International Institute for Population Sciences (IIPS) in Bombay, the Chancellor of Urdu University voiced his concerns about overpopulation in India. During the speaker's tenure as Health Minister of Maharashtra, he implemented a sterilization incentive program that resulted in the state's having the best family planning (FP) statistics in India for almost 10 years. The incentive program, however, was misused by overenthusiastic officials in other states, with the result that the FP program was renamed the Family Welfare Programme. Population is growing in India because of improvements in health care, but the population education necessary to change fertility will require more time than the seriousness of the population problem allows. In the longterm, poverty and illiteracy must be addressed to control population. In the meanwhile, the graduate program at the IIPS should be expanded to include an undergraduate program, marriage age laws should be enforced, and misconceptions about religious objections to FP must be addressed. India can not afford to use the measures forwarded by developed countries to control population growth. India must integrate population control efforts with the provision of health care because if population continues to grow in the face of reduced infant mortality and longer life expectancy, future generations will be forced to live in a state of poverty and economic degradation.

  20. The Urban Heat Island Effect and the Role of Vegetation to Address the Negative Impacts of Local Climate Changes in a Small Brazilian City

    Directory of Open Access Journals (Sweden)

    Elis Dener Lima Alves

    2017-02-01

    Full Text Available This study analyzes the influence of urban-geographical variables on determining heat islands and proposes a model to estimate and spatialize the maximum intensity of urban heat islands (UHI. Simulations of the UHI based on the increase of normalized difference vegetation index (NDVI, using multiple linear regression, in Iporá (Brazil are also presented. The results showed that the UHI intensity of this small city tended to be lower than that of bigger cities. Urban geometry and vegetation (UI and NDVI were the variables that contributed the most to explain the variability of the maximum UHI intensity. It was observed that areas located in valleys had lower thermal values, suggesting a cool island effect. With the increase in NDVI in the central area of a maximum UHI, there was a significant decrease in its intensity and size (a 45% area reduction. It is noteworthy that it was possible to spatialize the UHI to the whole urban area by using multiple linear regression, providing an analysis of the urban set from urban-geographical variables and thus performing prognostic simulations that can be adapted to other small tropical cities.

  1. Inaugural address

    Science.gov (United States)

    Joshi, P. S.

    2014-03-01

    From jets to cosmos to cosmic censorship P S Joshi Tata Institute of Fundamental Research, Homi Bhabha Road, Colaba, Mumbai 400005, India E-mail: psj@tifr.res.in 1. Introduction At the outset, I should like to acknowledge that part of the title above, which tries to capture the main flavour of this meeting, and has been borrowed from one of the plenary talks at the conference. When we set out to make the programme for the conference, we thought of beginning with observations on the Universe, but then we certainly wanted to go further and address deeper questions, which were at the very foundations of our inquiry, and understanding on the nature and structure of the Universe. I believe, we succeeded to a good extent, and it is all here for you in the form of these Conference Proceedings, which have been aptly titled as 'Vishwa Mimansa', which could be possibly translated as 'Analysis of the Universe'! It is my great pleasure and privilege to welcome you all to the ICGC-2011 meeting at Goa. The International Conference on Gravitation and Cosmology (ICGC) series of meetings are being organized by the Indian Association for General Relativity and Gravitation (IAGRG), and the first such meeting was planned and conducted in Goa in 1987, with subsequent meetings taking place at a duration of about four years at various locations in India. So, it was thought appropriate to return to Goa to celebrate the 25 years of the ICGC meetings. The recollections from that first meeting have been recorded elsewhere here in these Proceedings. The research and teaching on gravitation and cosmology was initiated quite early in India, by V V Narlikar at the Banares Hindu University, and by N R Sen in Kolkata in the 1930s. In course of time, this activity grew and gained momentum, and in early 1969, at the felicitation held for the 60 years of V V Narlikar at a conference in Ahmedabad, P C Vaidya proposed the formation of the IAGRG society, with V V Narlikar being the first President. This

  2. Presidential address.

    Science.gov (United States)

    Rao, L

    1984-01-01

    Stressed in this address is the crucial stage of the population boom, peeculiar to developing countries. The phenomenal rise in India's population, over the last 10 years, is particularly emphasized as it may thwart attempts for socioeconnomic development. Population and development are congruent concerns which need to be pursued simultaneously, and family planning must be accorded the highest priority in national efforts. In its attempts to curb its population explosion, India has witnessed significant progress in health and family welfare work in its march towards the goal of health for all. Recently, the focus has been on primary health care with its emphasis on prevention against risk of disease. The key element of the goal of health for all is the provision of primary health care to all, especially those who are poor. The new 20-Point Programme of India pinpoints areas of special thrust which show immediate tangible results in health and family welfare and the increase of primary health care facilities. Family planning is discussed as a people's movement in which the government's role is that of educator in contraceptive methodds so the people can be motivated to choose, on their own, anyone of them. Trained government personnel, service facilities and contraceptive supplies are being promoted for that goal. The energies of all social, political, religious and cultural organizations have to be channelled and utilized in the process of educating the people and making them adopt the small family norm. Graduates are urged to utilize their knowledge in the service of their country.

  3. Overexpression of the Rice SUMO E3 Ligase Gene OsSIZ1 in Cotton Enhances Drought and Heat Tolerance, and Substantially Improves Fiber Yields in the Field under Reduced Irrigation and Rainfed Conditions

    Science.gov (United States)

    Mishra, Neelam; Sun, Li; Zhu, Xunlu; Smith, Jennifer; Prakash Srivastava, Anurag; Yang, Xiaojie; Pehlivan, Necla; Esmaeili, Nardana; Luo, Hong; Shen, Guoxin; Jones, Don; Auld, Dick; Burke, John

    2017-01-01

    The Arabidopsis SUMO E3 ligase gene AtSIZ1 plays important roles in plant response to abiotic stresses as loss of function in AtSIZ1 leads to increased sensitivity to drought, heat and salt stresses. Overexpression of the AtSIZ1 rice homolog, OsSIZ1, leads to increased heat and drought tolerance in bentgrass, suggesting that the function of the E3 ligase SIZ1 is highly conserved in plants and it plays a critical role in abiotic stress responses. To test the possibility that the SUMO E3 ligase could be used to engineer drought- and heat-tolerant crops, the rice gene OsSIZ1 was overexpressed in cotton. We report here that overexpression of OsSIZ1 in cotton results in higher net photosynthesis and better growth than wild-type cotton under drought and thermal stresses in growth chamber and greenhouse conditions. Additionally, this tolerance to abiotic stresses was correlated with higher fiber yield in both controlled-environment and field trials carried out under reduced irrigation and rainfed conditions. These results suggest that OsSIZ1 is a viable candidate gene to improve crop yields under water-limited and rainfed agricultural production systems. PMID:28340002

  4. Ninth annual coal-fueled heat engines, advanced pressurized fluidized bed combustion, and gas stream cleanup systems contractors review meeting: Welcoming address

    International Nuclear Information System (INIS)

    Salvador, L.A.

    1992-01-01

    The market for retrofit and new capacity in the electric utility is expected to be very large: 250 gigawatt (GW) and 500 GW by the year 2030--an amount which equals the presently installed capacity in the US Overseas, the market is even larger exclamation point This large market will be driven by a number of key ''drivers.'' In order for power generation systems to compete in this market, they will have to satisfy the market drivers. This will lead us inevitably to modular, low cost, super clean, efficient, and reliable products which are fuel flexible and can meet either retrofit, repowering, or new capacity applications. I believe clean coal technologies that we are developing will meet these market demands and will penetrate--and eventually dominate--the power generation market of the next century. But for this market penetration and widespread deployment to take place, the products we are jointly developing must be continuously improved. We must together set our goals on a rapid march down the learning curve from the present high ''projected costs'' of these systems to an acceptable market clearing price on the order of $1000 to $1200 per kilowatt (kw) and with heat rates approaching 7500 Btu per kilowatt-hour (kWh). The projected learning curve for integrated gasification combined cycle systems is a good illustration of the aggressive goals we need to achieve

  5. Convocation address.

    Science.gov (United States)

    Ghatowar, P S

    1993-07-01

    The Union Deputy Minister of Health and Family Welfare in India addressed the 35th convocation of the International Institute for Population Sciences in Bombay in 1993. Officials in developing countries have been concerned about population growth for more than 30 years and have instituted policies to reduce population growth. In the 1960s, population growth in developing countries was around 2.5%, but today it is about 2%. Despite this decline, the world will have 1 billion more individuals by the year 2001. 95% of these new people will be born in developing countries. India's population size is so great that India does not have the time to wait for development to reduce population growth. Population needs to be viewed as an integrated part of overall development, since it is linked to poverty, illiteracy, environmental damage, gender issues, and reproductive health. Despite a large population size, India has made some important advancements in health and family planning. For example, India has reduced population growth (to 2.14% annually between 1981-1991), infant mortality, and its birth rate. It has increased the contraceptive use rate and life expectancy. Its southern states have been more successful at achieving demographic goals than have the northern states. India needs to implement efforts to improve living conditions, to change attitudes and perceptions about small families and contraception, and to promote family planning acceptance earlier among young couples. Improvement of living conditions is especially important in India, since almost 33% of the people live in poverty. India needs to invest in nutrition, health, and education. The mass media and nongovernmental organizations need to create population awareness and demand for family planning services. Improvement in women's status accelerates fertility decline, as has happened in Kerala State. The government needs to facilitate generation of jobs. Community participation is needed for India to achieve

  6. Keynote address

    International Nuclear Information System (INIS)

    Davis, J.M.

    1991-01-01

    DOE biomass R ampersand D programs have the potential to provide America with both plentiful, clean-burning domestic transportation fuels and cost-competitive industrial and utility fuels, benefiting energy security in the United States. Biofuels developed under our programs will also help improve air quality, reduce greenhouse gases, reduce the large daily quantities of waste we produce, and revitalize rural America. These research motivations have been documented in the National Energy Strategy. DOE looks forward to expanding its biofuels research program and to forging a partnership with private sector for cost-shared commercialization of new fuels and vehicle technologies. Many alternative fuels (e.g., ethanol, methanol, compressed natural gas, propane, or electricity) are candidates for gaining market share. Indeed, there may be significant regional variation in the future fuel mix. Alcohol fuels from biomass, particularly ethanol, have the potential to make a major contribution. Currently, ethanol in the United States is almost entirely made from corn; and the limitations of that process are well known (e.g., costly feedstock, end product requiring subsidy to be competitive, use of fossil fuels in renewable feedstock production and processing, and potential adverse impact of corn ethanol production on the price of food). To address these concerns, the DOE biofuels program is pursuing an ambitious research program to develop the technologies needed to convert these crops into alternative transportation fuels, primarily cellulose-based ethanol and methanol. Program R ampersand D has reduced the estimated cost per gallon of cellulose-based ethanol from $3.60 in 1980 to the current $1.35, with a program goal of $0.60 by the year 2000. DOE is also investigating the thermochemical conversion of biomass to methanol. The program goal is to achieve commercial production of methanol (like ethanol) at the gasoline equivalent of $0.90 per gallon by the year 2000. 4 figs

  7. Welcome Address

    Science.gov (United States)

    Kiku, H.

    2014-12-01

    Ladies and Gentlemen, It is an honor for me to present my welcome address in the 3rd International Workshop on "State of the Art in Nuclear Cluster Physics"(SOTANCP3), as the president of Kanto Gakuin University. Particularly to those from abroad more than 17 countries, I am very grateful for your participation after long long trips from your home to Yokohama. On the behalf of the Kanto Gakuin University, we certainly welcome your visit to our university and stay in Yokohama. First I would like to introduce Kanto Gakuin University briefly. Kanto Gakuin University, which is called KGU, traces its roots back to the Yokohama Baptist Seminary founded in 1884 in Yamate, Yokohama. The seminary's founder was Albert Arnold Bennett, alumnus of Brown University, who came to Japan from the United States to establish a theological seminary for cultivating and training Japanese missionaries. Now KGU is a major member of the Kanto Gakuin School Corporation, which is composed of two kindergartens, two primary schools, two junior high schools, two senior high schools as well as KGU. In this university, we have eight faculties with graduate school including Humanities, Economics, Law, Sciences and Engineering, Architecture and Environmental Design, Human and Environmental Studies, Nursing, and Law School. Over eleven thousands students are currently learning in our university. By the way, my major is the geotechnical engineering, and I belong to the faculty of Sciences and Engineering in my university. Prof. T. Yamada, here, is my colleague in the same faculty. I know that the nuclear physics is one of the most active academic fields in the world. In fact, about half of the participants, namely, more than 50 scientists, come from abroad in this conference. Moreover, I know that the nuclear physics is related to not only the other fundamental physics such as the elementary particle physics and astrophysics but also chemistry, medical sciences, medical cares, and radiation metrology

  8. Opening address

    International Nuclear Information System (INIS)

    Henrich, E.W.

    2005-01-01

    Full text: It is an honour for me to make this opening address on behalf of the European Commission which has cooperated with the International Atomic Energy Agency in organizing this Conference, and in particular on behalf of Hans Forsstroem from the Directorate-General, Research, who will arrive only later this week. Protection of the environment is, and will continue to be, an important consideration in the development and application of soundly based radiation protection standards. Current standards rest largely on the premise that, in protecting man, the environment is afforded an adequate level of protection. While this premise is broadly accepted by the radiation protection profession, it has come under increasing challenge in recent years. This challenge has not arisen because of any observable damage to the environment while operating within current standards. Rather, it has different origins including: - The robustness of the premise that protection of man affords protection of the environment, in particular the extent to which it is based on value judgements as opposed to rigorous scientific argument; - The more explicit inclusion of protection of the environment into national legislation on radiation protection and the need to demonstrate compliance; - A desire to achieve greater comparability between radiation and other pollutants. These trends were recognized by the Commission in the late 1990s and, as a result, the topic of protection of the environment was included as an important element of the European Union's 5th Research Framework Programme. Community support has been given to the FASSET project about which we will hear much during this Conference. This multinational project is providing much of the scientific basis underpinning and informing ongoing discussions on the development of a system of protection for the environment. Much, however, remains to be done to establish a well conceived and practicable system for protection of the environment

  9. QTLs and potential candidate genes for heat stress tolerance identified from the mapping populations specifically segregating for Fv/Fm in wheat

    DEFF Research Database (Denmark)

    Sharma, Dew Kumari; Torp, Anna Maria; Rosenqvist, Eva

    2017-01-01

    Despite the fact that F-v/F-m (maximum quantum efficiency of photosystem II) is the most widely used parameter for a rapid non-destructive measure of stress detection in plants, there are barely any studies on the genetic understanding of this trait under heat stress. Our aim was to identify...... quantitative trait locus (QTL) and the potential candidate genes linked to F-v/F-m for improved photosynthesis under heat stress in wheat (Triticum aestivum L.). Three bi-parental F-2 mapping populations were generated by crossing three heat tolerant male parents (origin: Afghanistan and Pakistan) selected...... for high F-v/F-m with a common heat susceptible female parent (origin: Germany) selected for lowest F-v/F-m out of a pool of 1274 wheat cultivars of diverse geographic origin. Parents together with 140 F-2 individuals in each population were phenotyped by F-v/F-m under heat stress (40 degrees C for 3 days...

  10. Heat transfer measurements on an incidence-tolerant low pressure turbine blade in a high speed linear cascade at low to moderate Reynolds numbers

    Science.gov (United States)

    Moualeu, Leolein Patrick Gouemeni

    Runway-independent aircraft are expected to be the future for short-haul flights by improving air transportation and reducing area congestion encountered in airports. The Vehicle Systems Program of NASA identified a Large Civil Tilt-Rotor, equipped with variable-speed power-turbine engines, as the best concept. At cruise altitude, the engine rotor-speed will be reduced by as much as the 50% of take-off speed. The large incidence variation in the low pressure turbine associated with the change in speed can be detrimental to the engine performance. Low pressure turbine blades in cruise altitude are more predisposed to develop regions of boundary layer separation. Typical phenomenon such as impinging wakes on downstream blades and mainstream turbulences enhance the complexity of the flow in low pressure turbines. It is therefore important to be able to understand the flow behavior to accurately predict the losses. Research facilities are seldom able to experimentally reproduce low Reynolds numbers at relevant engine Mach number. Having large incidence swing as an additional parameter in the investigation of the boundary layer development, on a low pressure turbine blade, makes this topic unique and as a consequence requires a unique facility to conduct the experimental research. The compressible flow wind tunnel facility at the University of North Dakota had been updated to perform steady state experiments on a modular-cascade, designed to replicate a large variation of the incidence angles. The high speed and low Reynolds number facility maintained a sealed and closed loop configuration for each incidence angle. The updated facility is capable to produce experimental Reynolds numbers as low as 45,000 and as high as 570,000 at an exit Mach number of 0.72. Pressure and surface temperature measurements were performed at these low pressure turbine conditions. The present thesis investigates the boundary layer development on the surface of an Incidence-tolerant blade. The

  11. Cryogenic heat transfer

    CERN Document Server

    Barron, Randall F

    2016-01-01

    Cryogenic Heat Transfer, Second Edition continues to address specific heat transfer problems that occur in the cryogenic temperature range where there are distinct differences from conventional heat transfer problems. This updated version examines the use of computer-aided design in cryogenic engineering and emphasizes commonly used computer programs to address modern cryogenic heat transfer problems. It introduces additional topics in cryogenic heat transfer that include latent heat expressions; lumped-capacity transient heat transfer; thermal stresses; Laplace transform solutions; oscillating flow heat transfer, and computer-aided heat exchanger design. It also includes new examples and homework problems throughout the book, and provides ample references for further study.

  12. Mycobacterial heat shock protein 65 (mbHSP65)-induced atherosclerosis: Preventive oral tolerization and definition of atheroprotective and atherogenic mbHSP65 peptides.

    Science.gov (United States)

    Grundtman, Cecilia; Jakic, Bojana; Buszko, Maja; Onestingel, Elisabeth; Almanzar, Giovanni; Demetz, Egon; Dietrich, Hermann; Cappellano, Giuseppe; Wick, Georg

    2015-09-01

    The aim of this study was to identify atherogenic and atheroprotective peptides of bacterial HSP60 [taking mycobacterial HSP65 (mbHSP65) as a potent paradigmatic representative] that could be used as candidates for an orally applied tolerizing vaccine against atherosclerosis. ApoE(-/-) mice were immunized with mbHSP65 protein or peptides, given mbHSP65 orally and then kept either on chow or high cholesterol diet. Atherosclerosis was assessed by en face and immunohistological analysis. Anti-HSP autoantibodies were detected by ELISA. The number and in vitro suppressive function of splenic and lymph node regulatory T cells (Tregs) were analyzed by flow cytometry. Specific T cell reactivity against mbHSP65 protein or peptides was assessed by proliferation assay. Decreased lesion size was accompanied by (a) increased splenic Treg numbers; (b) increased interleukin (IL)-10 mRNA levels in the aorta; (c) increased levels of anti-mbHSP65 and anti-mouse HSP60 antibodies pointing to pro-eukaryotic HSP60 humoral crossreaction, not curtailed by oral tolerization; (d) most importantly, we identified and functionally characterized novel atherogenic and atheroprotective mbHSP65 epitopes. Atheroprotective mbHSP65 peptides may be considered as potential candidates for the development of a tolerizing vaccine to prevent and treat atherosclerosis, while keeping protective immunity to non-atherogenic domains of mbHSP65 intact. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. The trade-off between heat tolerance and metabolic cost drives the bimodal life strategy at the air-water interface

    KAUST Repository

    Fusi, Marco

    2016-01-13

    The principle of oxygen and capacity limitation of thermal tolerance in ectotherms suggests that the long-term upper limits of an organism\\'s thermal niche are equivalent to the upper limits of the organism\\'s functional capacity for oxygen provision to tissues. Air-breathing ectotherms show wider thermal tolerances, since they can take advantage of the higher availability of oxygen in air than in water. Bimodal species move from aquatic to aerial media and switch between habitats in response to environmental variations such as cyclical or anomalous temperature fluctuations. Here we tested the prediction that bimodal species cope better with thermal stress than truly aquatic species using the crab Pachygrapsus marmoratus as a model species. When in water, oxygen consumption rates of P. marmoratus acutely rise during warming. Beyond a temperature threshold of 23 °C the crab\\'s aerobic metabolism in air remains lower than in water. In parallel, the haemolymph oxygen partial pressure of submerged animals progressive decreases during warming, while it remains low but constant during emersion. Our results demonstrate the ability of a bimodal breathing ectotherm to extend its thermal tolerance during air-breathing, suggesting that there are temperature-related physiological benefits during the evolution of the bimodal life style.

  14. Address Points - Allegheny County Address Points 201601

    Data.gov (United States)

    NSGIC Education | GIS Inventory — This dataset contains Address Points in Allegheny County. The Address Points were created by GDR for the Allegheny County CAD project, October 2008. Data is updated...

  15. Multiple heat priming enhances thermo-tolerance to a later high temperature stress via improving subcellular antioxidant activities in wheat seedlings

    DEFF Research Database (Denmark)

    Wang, Xiao; Cai, Jian; Liu, Fulai

    2014-01-01

    Seedlings of winter wheat (Triticum aestivum L.) were firstly twice heat-primed at 32/24 °C, and subsequently subjected to a more severe high temperature stress at 35/27 °C. The later high temperature stress significantly decreased plant biomass and leaf total soluble sugars concentration. Howeve...

  16. Using genotyping-by-sequencing to develop broccoli markers for construction of a high-density linkage map and to identify quantitative trait loci associated with heat tolerance

    Science.gov (United States)

    Heat stress reduces the yield and quality of broccoli heads imposing seasonal and geographic limits to broccoli production. For the most part, the risk of producing broccoli with head defects (uneven beads, bracts in heads, etc.) induced by high temperatures has restricted commercial production in t...

  17. Comparative proteomic analysis of the hepatic response to heat stress in Muscovy and Pekin ducks: insight into thermal tolerance related to energy metabolism.

    Directory of Open Access Journals (Sweden)

    Tao Zeng

    Full Text Available The Pekin duck, bred from the mallard (Anas platyrhynchos in china, is one of the most famous meat duck species in the world. However, it is more sensitive to heat stress than Muscovy duck, which is believed to have originated in South America. With temperature raising, mortality, laying performance, and meat quality of the Pekin duck are severely affected. This study aims to uncover the temperature-dependent proteins of two duck species using comparative proteomic approach. Duck was cultured under 39°C ± 0.5°C for 1 h, and then immediately returned to 20°C for a 3 h recovery period, the liver proteins were extracted and electrophoresed in two-dimensional mode. After analysis of gel images, 61 differentially expressed proteins were detected, 54 were clearly identified by MALDI TOF/TOF MS. Of the 54 differentially expressed protein spots identified, 7 were found in both species, whereas 47 were species specific (25 in Muscovy duck and 22 in Pekin duck. As is well known, chaperone proteins, such as heat shock protein (HSP 70 and HSP10, were abundantly up-regulated in both species in response to heat stress. However, we also found that several proteins, such as α-enolase, and S-adenosylmethionine synthetase, showed different expression patterns in the 2 duck species. The enriched biological processes were grouped into 3 main categories according to gene ontology analysis: cell death and apoptosis (20.93%, amino acid metabolism (13.95% and oxidation reduction (20.93%. The mRNA levels of several differentially expressed protein were investigated by real-time RT-PCR. To our knowledge, this study is the first to provide insights into the differential expression of proteins following heat stress in ducks and enables better understanding of possible heat stress response mechanisms in animals.

  18. Evaluating Agronomic Performance and Investigating Molecular Structure of Drought and Heat Tolerant Wild Alfalfa (Medicago sativa L.) Collection from the Southeastern Turkey.

    Science.gov (United States)

    Basbag, Mehmet; Aydin, Ali; Sakiroglu, Muhammet

    2017-02-01

    Drought is a major stress factor for agricultural production including alfalfa production. One way to counterbalance the yield losses is the introgression of drought tolerant germplasm into breeding programs. As an effort to exploit such germplasm, 16 individual plants were selected from the Southeastern Turkey from their natural habitat and clonally propagated in field trials with an ultimate goal to use the germplasm as parents for releasing a synthetic cultivar. Forage yield and forage quality traits were evaluated and molecular genetic diversity among genotypes were determined using inter simple sequence repeat markers. Genotypes showed a variation from growth habit to yield and quality traits indicating sufficient phenotypic variation for diverse breeding efforts (for grazing or harvesting) and long term selection schemes. A large amount of genetic variation was observed even with a limited number of marker and genotypes. However, no pattern of spatial genetic structure was observed for the scale of the study when genetic variation is linked to the geographic origin. We conclude that ex situ natural variation provides a wealth of germplasm that could be incorporated into breeding programs aiming to improve drought tolerance. We also suggest an extensive collection of seeds/plant tissue from unique plants with desirable traits rather than putting more efforts to create a spatial germplasm sampling efforts in narrow regions.

  19. Influence of acclimation to sublethal temperature on heat tolerance of Tribolium castaneum (Herbst (Coleoptera: Tenebrionidae exposed to 50°C.

    Directory of Open Access Journals (Sweden)

    Jianhua Lü

    Full Text Available Tribolium castaneum (Herbst (Coleoptera: Tenebrionidae is a serious pest of stored agricultural products and one of the most common insects found in grain storage and food processing facilities. Heat treatment has been revisited to control stored-product insects as a potential alternative to methyl bromide for disinfesting mills and food-processing facilities. The influence of acclimation of T. castaneum adults, pupae, larvae, and eggs to sublethal temperatures of 36, and 42°C on their subsequent susceptibility to lethal temperature of 50°C was respectively investigated. The acclimation of T. castaneum eggs, larvae, pupae, and adults to 36, and 42°C significantly decreased their subsequent susceptibility to lethal high temperature of 50°C. The influence of acclimation to 42°C was significantly greater than that of acclimation to 36°C. The most influential acclimation times at 42°C for mortality of T. castaneum eggs, larvae, pupae, and adults were 15, 5, 5, and 5 h, respectively, and their corresponding mortality were 41.24, 5.59, 20.19, and 4.48%, compared to 100% mortality of T. castaneum eggs, larvae, pupae, and adults without acclimation when exposed to 50°C for 35 min, respectively. The present results have important implications for developing successful heat treatment protocols to control T. castaneum, improving disinfestation effectiveness of heat treatment and understanding insect response to high temperatures.

  20. Allegheny County Addressing Landmarks

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...

  1. Allegheny County Address Points

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains address points which represent physical address locations assigned by the Allegheny County addressing authority. Data is updated by County...

  2. Relationship between the Heat Tolerance of Photosynthesis and the Thermal Stability of Rubisco Activase in Plants from Contrasting Thermal Environments1

    Science.gov (United States)

    Salvucci, Michael E.; Crafts-Brandner, Steven J.

    2004-01-01

    Inhibition of net photosynthesis (Pn) by moderate heat stress has been attributed to an inability of Rubisco activase to maintain Rubisco in an active form. To examine this proposal, the temperature response of Pn, Rubisco activation, chlorophyll fluorescence, and the activities of Rubisco and Rubisco activase were examined in species from contrasting environments. The temperature optimum of Rubisco activation was 10°C higher in the creosote bush (Larrea tridentata) compared with the Antarctic hairgrass (Deschampsia antarctica), resembling the temperature response of Pn. Pn increased markedly with increasing internal CO2 concentration in Antarctic hairgrass and creosote bush plants subjected to moderate heat stress even under nonphotorespiratory conditions. Nonphotochemical quenching of chlorophyll fluorescence, the effective quantum yield of photochemical energy conversion (ΔF/Fm′) and the maximum yield of PSII (Fv/Fm) were more sensitive to temperature in Antarctic hairgrass and two other species endemic to cold regions (i.e. Lysipomia pumila and spinach [Spinacea oleracea]) compared with creosote bush and three species (i.e. jojoba [Simmondsia chinensis], tobacco [Nicotiana tabacum], and cotton [Gossypium hirsutum]) from warm regions. The temperature response of activity and the rate of catalytic inactivation of Rubisco from creosote bush and Antarctic hairgrass were similar, whereas the optimum for ATP hydrolysis and Rubisco activation by recombinant creosote bush, cotton, and tobacco activase was 8°C to 10°C higher than for Antarctic hairgrass and spinach activase. These results support a role for activase in limiting photosynthesis at high temperature. PMID:15084731

  3. Controle genético e tolerância ao estresse de calor em populações híbridas e em cultivares de trigo Genetic control and tolerance to the heat stress in wheat hybrid population and cultivars

    Directory of Open Access Journals (Sweden)

    Moacil Alves de Souza

    2001-10-01

    Full Text Available O objetivo deste trabalho foi obter informações sobre o controle genético da produtividade de grãos de trigo sob condições de estresse de calor, o grau de tolerância ao estresse de calor de algumas cultivares e linhagens e a identificação de populações segregantes promissoras para a obtenção de linhagens adaptadas às condições da região central do Brasil. Foram avaliados 13 parentais e 40 populações provenientes de um dialelo parcial, nas gerações F1 e F2 em condições de campo, em Lavras e Patos de Minas, MG, com as semeaduras feitas no verão (fevereiro e no inverno (maio. Houve diferença de tolerância ao calor entre os parentais e entre as populações híbridas quanto ao caráter produção de grãos, e ambos os efeitos aditivos e não-aditivos foram importantes no controle genético deste caráter na presença ou ausência de calor. Apesar da ocorrência de interações populações x épocas de semeadura, a alta repetibilidade dos efeitos da capacidade geral de combinação permite inferir a possibilidade de acelerar os programas de melhoramento na região, efetuando-se a seleção tanto na época de verão quanto no inverno.The objective of this work was to get information about the genetic control of the grain yield under heat stress conditions, the tolerance of cultivar and the identification of promising segregation populations for selections of lines adapted to the conditions of the central region of Brazil. Thirteen parents and 40 populations in F1 and F2 generations derived by partial diallel crosses were evaluated. The experiments were conducted under field conditions in Lavras and Patos de Minas, MG, Brazil, sowing the seeds in the summertime (February and in the winter (May. There was difference of heat tolerance among parents and hybrid populations for grain yield character, and both additive and non-additive effects were important in the genetic control of grain yield character in the presence or absence

  4. Contrasting root and photosynthesis traits in a large-acreage Canadian durum variety and its distant parent of Algerian origin for assembling drought/heat tolerance attributes

    Science.gov (United States)

    Ashe, Paula; Shaterian, Hamid; Akhov, Leonid; Kulkarni, Manoj; Selvaraj, Gopalan

    2017-12-01

    In Canada, the world’s top exporter of high-protein durum, varietal development over its nearly six-decade history has been driven by a quest for yield improvement without compromise on grain protein content and other quality aspects. Pelissier, a landrace selection from Algeria that was introduced into North America more than a century ago and the variety Strongfield that was released in 2004 are notable. Pelissier, known to elaborate more roots and considered as drought tolerant, has been cultivated commercially and thus deemed adapted. Strongfield has Pelissier in its pedigree, and it remains a high-acreage variety. Strongfield was found to elaborate only about half of the root biomass of Pelissier at maturity in greenhouse trials under well-watered conditions. Extended drought stress caused a significant reduction in the root biomass of both lines. However, Pelissier under drought maintained at least as much root biomass as that of Strongfield under well-watered conditions. In comparison to Pelissier, it had a superior photosynthesis rate (27.16 µmol CO2 m-2 s-1), capacity for carboxylation (Vcmax: 132.83 µmol CO2 m-2 s-1) and electron transport/ribulose-1,5-bisphosphate (RuBP) regeneration (Jmax: 265.40 µmol CO2 m-2 s-1); the corresponding values for Pelissier were 19.62 µmol CO2 m-2 s-1, 91.87 µmol CO2 m-2 s-1, and 163.83 µmol CO2 m-2 s-1, respectively, under well-watered conditions. Under short-term/mild drought conditions, the carbon assimilation rate remained stable in Pelissier while it declined in Strongfield to the Pelissier level. However, Strongfield succumbed to extended drought sooner than Pelissier. Photosynthesis in Strongfield but not Pelissier was found to be sensitive to high temperature stress. These results provide encouraging prospects for further exploitation of beneficial physiological traits from Pelissier in constructing climate-resilient, agronomically favourable wheat ideotypes.

  5. The heat shock transcription factor PsHSF1 of Phytophthora sojae is required for oxidative stress tolerance and detoxifying the plant oxidative burst.

    Science.gov (United States)

    Sheng, Yuting; Wang, Yonglin; Meijer, Harold J G; Yang, Xinyu; Hua, Chenlei; Ye, Wenwu; Tao, Kai; Liu, Xiaoyun; Govers, Francine; Wang, Yuanchao

    2015-04-01

    In the interaction between plant and microbial pathogens, reactive oxygen species (ROS) rapidly accumulate upon pathogen recognition at the infection site and play a central role in plant defence. However, the mechanisms that plant pathogens use to counteract ROS are still poorly understood especially in oomycetes, filamentous organisms that evolved independently from fungi. ROS detoxification depends on transcription factors (TFs) that are highly conserved in fungi but much less conserved in oomycetes. In this study, we identified the TF PsHSF1 that acts as a modulator of the oxidative stress response in the soybean stem and root rot pathogen Phytophthora sojae. We found that PsHSF1 is critical for pathogenicity in P. sojae by detoxifying the plant oxidative burst. ROS produced in plant defence can be detoxified by extracellular peroxidases and laccases which might be regulated by PsHSF1. Our study extends the understanding of ROS detoxification mechanism mediated by a heat shock TF in oomycetes. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  6. Salinity tolerance of Populus.

    Science.gov (United States)

    Chen, S; Polle, A

    2010-03-01

    The genus Populus has a wide distribution in different climatic zones. Besides its economic and ecological relevance, Populus also serves as a model for elucidating physiological and molecular mechanisms of stress tolerance in tree species. In this review, adaptation strategies of poplars to excess soil salinity are addressed at different scales, from the cellular to the whole-plant level. Striking differences in salt tolerance exist among different poplar species and ecotypes, with Populus euphratica being outstanding in this respect. Key mechanisms identified in this species to mediate salt tolerance are compartmentalisation of Cl(-) in the vacuoles of the root cortex cells, diminished xylem loading of NaCl, activation of Na(+) extrusion into the soil solution under stress, together with simultaneously avoiding excessive K(+) loss by regulation of depolarisation-activated cation channels. This leads to improved maintenance of the K(+)/Na(+) balance, a crucial precondition for survival under salt stress. Leaf cells of this species are able to compartmentalise Na(+) preferentially in the apoplast, whereas in susceptible poplar species, as well as in crop plants, vacuolar Na(+) deposition precedes apoplastic transport. ABA, Ca(2+)and ROS are involved in stress sensing, with higher or faster activation of defences in tolerant than in susceptible poplar species. P. euphratica develops leaf succulence after prolonged salt exposure as a plastic morphological adaptation that leads to salt dilution. Transgenic approaches to improve salt tolerance by transformation of candidate genes have had limited success, since salt tolerance is a multigenic trait. In future attempts towards increased salt resistance, barriers between different poplar sections must be overcome and application of novel biotechnological tools, such as gene stacking, are recommended.

  7. Plasticity in thermal tolerance has limited potential to buffer ectotherms from global warming

    Science.gov (United States)

    Gunderson, Alex R.; Stillman, Jonathon H.

    2015-01-01

    Global warming is increasing the overheating risk for many organisms, though the potential for plasticity in thermal tolerance to mitigate this risk is largely unknown. In part, this shortcoming stems from a lack of knowledge about global and taxonomic patterns of variation in tolerance plasticity. To address this critical issue, we test leading hypotheses for broad-scale variation in ectotherm tolerance plasticity using a dataset that includes vertebrate and invertebrate taxa from terrestrial, freshwater and marine habitats. Contrary to expectation, plasticity in heat tolerance was unrelated to latitude or thermal seasonality. However, plasticity in cold tolerance is associated with thermal seasonality in some habitat types. In addition, aquatic taxa have approximately twice the plasticity of terrestrial taxa. Based on the observed patterns of variation in tolerance plasticity, we propose that limited potential for behavioural plasticity (i.e. behavioural thermoregulation) favours the evolution of greater plasticity in physiological traits, consistent with the ‘Bogert effect’. Finally, we find that all ectotherms have relatively low acclimation in thermal tolerance and demonstrate that overheating risk will be minimally reduced by acclimation in even the most plastic groups. Our analysis indicates that behavioural and evolutionary mechanisms will be critical in allowing ectotherms to buffer themselves from extreme temperatures. PMID:25994676

  8. Plasticity in thermal tolerance has limited potential to buffer ectotherms from global warming.

    Science.gov (United States)

    Gunderson, Alex R; Stillman, Jonathon H

    2015-06-07

    Global warming is increasing the overheating risk for many organisms, though the potential for plasticity in thermal tolerance to mitigate this risk is largely unknown. In part, this shortcoming stems from a lack of knowledge about global and taxonomic patterns of variation in tolerance plasticity. To address this critical issue, we test leading hypotheses for broad-scale variation in ectotherm tolerance plasticity using a dataset that includes vertebrate and invertebrate taxa from terrestrial, freshwater and marine habitats. Contrary to expectation, plasticity in heat tolerance was unrelated to latitude or thermal seasonality. However, plasticity in cold tolerance is associated with thermal seasonality in some habitat types. In addition, aquatic taxa have approximately twice the plasticity of terrestrial taxa. Based on the observed patterns of variation in tolerance plasticity, we propose that limited potential for behavioural plasticity (i.e. behavioural thermoregulation) favours the evolution of greater plasticity in physiological traits, consistent with the 'Bogert effect'. Finally, we find that all ectotherms have relatively low acclimation in thermal tolerance and demonstrate that overheating risk will be minimally reduced by acclimation in even the most plastic groups. Our analysis indicates that behavioural and evolutionary mechanisms will be critical in allowing ectotherms to buffer themselves from extreme temperatures. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  9. Productivity of determinate growth tomato lines tolerant to heat under the organic system Produtividade de linhagens de tomate rasteiro tolerantes ao calor sob o sistema orgânico

    Directory of Open Access Journals (Sweden)

    Cândido A da Costa

    2011-12-01

    Full Text Available The objective of the present work was to evaluate the productive response of heat tolerant lines of determinate growth tomato under the organic production system. The experiment was carried out in the Instituto de Ciências Agrárias of UFMG, Montes Claros, Minas Gerais state, Brazil. The experimental design was of randomized complete blocks with eight treatments and four replications. The treatments consisted of eight heat tolerant processing type tomato lines obtained from the Asian Vegetable Research and Development Center (AVRDC, China: CLN1621L, CLN1621F, CLN1621E, CLN1466P, CLN2026E, CLN2026D, CLN2026C and CLN2001C. There was an inverse relationship between the average weight of the fruits and the number of fruits per plant. The highest average fruit weight of some lines was compensated by the lowest quantity of fruits, in such a way that there were no significant differences among the lines. Symptoms of nutritional deficiency and incidences of pests and diseases were not verified in any of the studied lines. All lines presented potential for genetic improvement research and cultivation using organic production systems under higher temperature conditions.O objetivo do presente trabalho foi avaliar o desempenho produtivo de linhagens de tomate rasteiro tolerantes ao calor sob o sistema orgânico de produção. O experimento foi realizado no Núcleo de Ciências Agrárias da UFMG, Montes Claros-MG. Foi utilizado o delineamento em blocos casualizados com oito tratamentos e quatro repetições. Os tratamentos consistiram de oito linhagens de tomate do tipo rasteiro tolerantes ao calor obtidos na Asian Vegetable Research and Development Center (AVRDC, China: CLN1621L, CLN1621F, CLN1621E, CLN1466P, CLN2026E, CLN2026D, CLN2026C e CLN2001C. Houve uma relação inversa entre o peso médio dos frutos e o número de frutos produzidos por planta. O maior peso médio de frutos de algumas linhagens foi compensado pelo menor número de frutos, de tal

  10. Intolerant tolerance.

    Science.gov (United States)

    Khushf, G

    1994-04-01

    The Hyde Amendment and Roman Catholic attempts to put restrictions on Title X funding have been criticized for being intolerant. However, such criticism fails to appreciate that there are two competing notions of tolerance, one focusing on the limits of state force and accepting pluralism as unavoidable, and the other focusing on the limits of knowledge and advancing pluralism as a good. These two types of tolerance, illustrated in the writings of John Locke and J.S. Mill, each involve an intolerance. In a pluralistic context where the free exercise of religion is respected, John Locke's account of tolerance is preferable. However, it (in a reconstructed form) leads to a minimal state. Positive entitlements to benefits like artificial contraception or nontherapeutic abortions can legitimately be resisted, because an intolerance has already been shown with respect to those that consider the benefit immoral, since their resources have been coopted by taxation to advance an end that is contrary to their own. There is a sliding scale from tolerance (viewed as forbearance) to the affirmation of communal integrity, and this scale maps on to the continuum from negative to positive rights.

  11. Stress response and tolerance of Zea mays to CeO2 nanoparticles: cross talk among H2O2, heat shock protein, and lipid peroxidation.

    Science.gov (United States)

    Zhao, Lijuan; Peng, Bo; Hernandez-Viezcas, Jose A; Rico, Cyren; Sun, Youping; Peralta-Videa, Jose R; Tang, Xiaolei; Niu, Genhua; Jin, Lixin; Varela-Ramirez, Armando; Zhang, Jian-ying; Gardea-Torresdey, Jorge L

    2012-11-27

    The rapid development of nanotechnology will inevitably release nanoparticles (NPs) into the environment with unidentified consequences. In addition, the potential toxicity of CeO(2) NPs to plants and the possible transfer into the food chain are still unknown. Corn plants (Zea mays) were germinated and grown in soil treated with CeO(2) NPs at 400 or 800 mg/kg. Stress-related parameters, such as H(2)O(2), catalase (CAT), and ascorbate peroxidase (APX) activity, heat shock protein 70 (HSP70), lipid peroxidation, cell death, and leaf gas exchange were analyzed at 10, 15, and 20 days post-germination. Confocal laser scanning microscopy was used to image H(2)O(2) distribution in corn leaves. Results showed that the CeO(2) NP treatments increased accumulation of H(2)O(2), up to day 15, in phloem, xylem, bundle sheath cells and epidermal cells of shoots. The CAT and APX activities were also increased in the corn shoot, concomitant with the H(2)O(2) levels. Both 400 and 800 mg/kg CeO(2) NPs triggered the up-regulation of the HSP70 in roots, indicating a systemic stress response. None of the CeO(2) NPs increased the level of thiobarbituric acid reacting substances, indicating that no lipid peroxidation occurred. CeO(2) NPs, at both concentrations, did not induce ion leakage in either roots or shoots, suggesting that membrane integrity was not compromised. Leaf net photosynthetic rate, transpiration, and stomatal conductance were not affected by CeO(2) NPs. Our results suggest that the CAT, APX, and HSP70 might help the plants defend against CeO(2) NP-induced oxidative injury and survive NP exposure.

  12. Reach Address Database (RAD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Reach Address Database (RAD) stores the reach address of each Water Program feature that has been linked to the underlying surface water features (streams,...

  13. Evaluating the Production of Doubled Haploid Wheat Lines Using Various Methods of Wheat and Maize Crossing to Develop Heat-Tolerant Wheat Varieties

    Directory of Open Access Journals (Sweden)

    Tayebeh BAKHSHI

    2017-02-01

    Full Text Available Abstract. In this study, chromosome elimination method was used to develop doubled haploid wheat lines via crosses with maize. The plant materials used included 11, F1 wheat genotypes and maize genotype BC572. In these crosses, the maize plant was used as the male parent.Three methods of haploid production in wheat comprising conventional (A, detached-tiller culture (B and intermediate (C techniques were used and compared. The traits such as the number of seeds set, the number of embryos obtained and the number of haploid seedlings produced were studied. Comparisons showed that among various methods of storing wheat spikes, method (C was better than other techniques in terms of the percentage of seed production, embryo formation and haploid seedling production. Also, in all three methods, the percentage of seed production, the percentage of embryo formation and the percentage of haploid seedling production were respectively equal to 76.84, 25.22 and 51.89. Among the wheat genotypes in all three methods, genotype DH-133 with 87.28 percent seed set and genotype DH-132 with 32.71 percent embryo formation and 65.08 percent haploid seedling production were the best genotypes. A total of 92 doubled haploid lines were produced. In the field evaluations of 86 doubled haploid lines, traits such as growing season, plant height, lodging, kernel yield and 1000 kernel weight were examined. Finally, 3 lines were selected for adaptation and stability testing under heat stress conditions.Keywords: Wheat, Doubled haploid, Chromosome elimination, Detached-tiller culture Özet. Bu çalışmada, mısır ile çaprazlarla çift katlı haploid buğday hatlarının geliştirilmesi için kromozom eliminasyon yöntemi kullanılmıştır. Kullanılan bitki materyalleri 11, F1 buğday genotipleri ve BC572 mısır genotipini içermektedir. Bu çaprazlarda, mısır bitkisi erkek ebeveyn olarak kullanılmıştır. Geleneksel (A, ayrık-yeke kültürü (B ve ara (C

  14. Antibiotic tolerance and microbial biofilms

    DEFF Research Database (Denmark)

    Folkesson, Anders

    Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We study the dynamics of antibiotic action within hydrodynamic flow chamber biofilms of Escherichia coli and Pseudomonas aeruginosa using isogenic mutants and fluorescent gene...... expression reporters and we address the question of how biofilm organization affects antibiotic susceptibility. The dynamics of microbial killing is monitored by viable count determination, and confocal laser microscopy. Our work shows that the apparent increased antibiotic tolerance is due to the formation...... of antibiotic tolerant subpopulations within the biofilm. The formation of these subpopulations is highly variable and dependent on the antibiotic used, the biofilm structural organization and the induction of specific tolerance mechanisms....

  15. Infectious Tolerance

    OpenAIRE

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, ...

  16. Heat exchangers and recuperators for high temperature waste gases

    Science.gov (United States)

    Meunier, H.

    General considerations on high temperature waste heat recovery are presented. Internal heat recovery through combustion air preheating and external heat recovery are addressed. Heat transfer and pressure drop in heat exchanger design are discussed.

  17. Infectious Tolerance

    Science.gov (United States)

    Jonuleit, Helmut; Schmitt, Edgar; Kakirman, Hacer; Stassen, Michael; Knop, Jürgen; Enk, Alexander H.

    2002-01-01

    Regulatory CD4+CD25+ T cells (Treg) are mandatory for maintaining immunologic self-tolerance. We demonstrate that the cell-cell contact–mediated suppression of conventional CD4+ T cells by human CD25+ Treg cells is fixation resistant, independent from membrane-bound TGF-β but requires activation and protein synthesis of CD25+ Treg cells. Coactivation of CD25+ Treg cells with Treg cell–depleted CD4+ T cells results in anergized CD4+ T cells that in turn inhibit the activation of conventional, freshly isolated CD4+ T helper (Th) cells. This infectious suppressive activity, transferred from CD25+ Treg cells via cell contact, is cell contact–independent and partially mediated by soluble transforming growth factor (TGF)-β. The induction of suppressive properties in conventional CD4+ Th cells represents a mechanism underlying the phenomenon of infectious tolerance. This explains previously published conflicting data on the role of TGF-β in CD25+ Treg cell–induced immunosuppression. PMID:12119350

  18. RAP2.4a Is Transported through the Phloem to Regulate Cold and Heat Tolerance in Papaya Tree (Carica papaya cv. Maradol): Implications for Protection Against Abiotic Stress.

    Science.gov (United States)

    Figueroa-Yañez, Luis; Pereira-Santana, Alejandro; Arroyo-Herrera, Ana; Rodriguez-Corona, Ulises; Sanchez-Teyer, Felipe; Espadas-Alcocer, Jorge; Espadas-Gil, Francisco; Barredo-Pool, Felipe; Castaño, Enrique; Rodriguez-Zapata, Luis Carlos

    2016-01-01

    Plants respond to stress through metabolic and morphological changes that increase their ability to survive and grow. To this end, several transcription factor families are responsible for transmitting the signals that are required for these changes. Here, we studied the transcription factor superfamily AP2/ERF, particularly, RAP2.4 from Carica papaya cv. Maradol. We isolated four genes (CpRap2.4a, CpRAap2.4b, CpRap2.1 and CpRap2.10), and an in silico analysis showed that the four genes encode proteins that contain a conserved APETALA2 (AP2) domain located within group I and II transcription factors of the AP2/ERF superfamily. Semiquantitative PCR experiments indicated that each CpRap2 gene is differentially expressed under stress conditions, such as extreme temperatures. Moreover, genetic transformants of tobacco plants overexpressing CpRap2.4a and CpRap2.4b genes show a high level of tolerance to cold and heat stress compared to non-transformed plants. Confocal microscopy analysis of tobacco transgenic plants showed that CpRAP2.4a and CpRAP2.4b proteins were mainly localized to the nuclei of cells from the leaves and roots and also in the sieve elements. Moreover, the movement of CpRap2.4a RNA in tobacco grafting was analyzed. Our results indicate that CpRap2.4a and CpRap2.4b RNA in the papaya tree have a functional role in the response to stress conditions such as exposure to extreme temperatures via direct translation outside the parental RNA cell.

  19. RAP2.4a Is Transported through the Phloem to Regulate Cold and Heat Tolerance in Papaya Tree (Carica papaya cv. Maradol: Implications for Protection Against Abiotic Stress.

    Directory of Open Access Journals (Sweden)

    Luis Figueroa-Yañez

    Full Text Available Plants respond to stress through metabolic and morphological changes that increase their ability to survive and grow. To this end, several transcription factor families are responsible for transmitting the signals that are required for these changes. Here, we studied the transcription factor superfamily AP2/ERF, particularly, RAP2.4 from Carica papaya cv. Maradol. We isolated four genes (CpRap2.4a, CpRAap2.4b, CpRap2.1 and CpRap2.10, and an in silico analysis showed that the four genes encode proteins that contain a conserved APETALA2 (AP2 domain located within group I and II transcription factors of the AP2/ERF superfamily. Semiquantitative PCR experiments indicated that each CpRap2 gene is differentially expressed under stress conditions, such as extreme temperatures. Moreover, genetic transformants of tobacco plants overexpressing CpRap2.4a and CpRap2.4b genes show a high level of tolerance to cold and heat stress compared to non-transformed plants. Confocal microscopy analysis of tobacco transgenic plants showed that CpRAP2.4a and CpRAP2.4b proteins were mainly localized to the nuclei of cells from the leaves and roots and also in the sieve elements. Moreover, the movement of CpRap2.4a RNA in tobacco grafting was analyzed. Our results indicate that CpRap2.4a and CpRap2.4b RNA in the papaya tree have a functional role in the response to stress conditions such as exposure to extreme temperatures via direct translation outside the parental RNA cell.

  20. The role of heat-tolerant endotoxin-retentive ultrafilters (UFs) for the remediation of reverse osmosis (RO) plants employed for surgical hand antisepsis using periodic thermal disinfection -A ten-year longitudinal experience study in the operating theater.

    Science.gov (United States)

    Uetera, Yushi; Yasuhara, Hiroshi; Kumada, Naohito; Misawa, Yoshiki; Terada, Yoshiyuki; Satou, Yoshio; Suhara, Tamaki; Kawamura, Kunio

    2018-03-15

    Recently, the use of filters has come into light for sanitizing water plants. This study investigated the role of heat-tolerant ultrafilters (UFs) for the remediation of reverse osmosis (RO) plants using periodic thermal disinfection. Two completely identical RO plants (RO plants A & B) were installed in 2006 for surgical hand antisepsis in the operating theater. RO water was stored in the 300-liter storage tank and re-circulated in the 190 meter-long loop delivering water to 12 faucets in each RO plant. Periodic thermal disinfection has come into practice since a UF module was retrofitted to the recirculation loop of each RO plant in 2010. Endotoxin was monitored closely before and after thermal disinfection. Before UF modules were retrofitted, endotoxin increased to a maximum of 0.301 EU/ml in the RO plant A and 1.446 EU/ml in the RO plant B after thermal disinfection, respectively. Since a UF module was retrofitted to each RO plant in 2010, endotoxin has been continuously below 0.025 EU/ml in the RO plant A and exceeded this level five times in the RO plant B. On one occasion, endotoxin increased in all samples collected simultaneously after solenoid valves were replaced in the recirculation loop near the air conditioner outlet. At this time, the inside of pipework was exposed to the ventilation airflow. After the valves were replaced again with the work place isolated using a curing sheet, endotoxin decreased. On the other occasions, endotoxin increased only in one sample and decreased after thermal disinfection. Annually replaced UF modules were examined twice for estimating the amounts of immobilized endotoxin. The estimated amounts decreased in 2013 by the order of 10-3 in comparison with those in 2011 in both RO plants. The present study suggested that UFs acted synergistically with periodic thermal disinfection for the remediation of RO plants. Copyright © 2018, Parenteral Drug Association.

  1. Addressing Ozone Layer Depletion

    Science.gov (United States)

    Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.

  2. Addressivity in cogenerative dialogues

    Science.gov (United States)

    Hsu, Pei-Ling

    2014-03-01

    Ashraf Shady's paper provides a first-hand reflection on how a foreign teacher used cogens as culturally adaptive pedagogy to address cultural misalignments with students. In this paper, Shady drew on several cogen sessions to showcase his journey of using different forms of cogens with his students. To improve the quality of cogens, one strategy he used was to adjust the number of participants in cogens. As a result, some cogens worked and others did not. During the course of reading his paper, I was impressed by his creative and flexible use of cogens and at the same time was intrigued by the question of why some cogens work and not others. In searching for an answer, I found that Mikhail Bakhtin's dialogism, especially the concept of addressivity, provides a comprehensive framework to address this question. In this commentary, I reanalyze the cogen episodes described in Shady's paper in the light of dialogism. My analysis suggests that addressivity plays an important role in mediating the success of cogens. Cogens with high addressivity function as internally persuasive discourse that allows diverse consciousnesses to coexist and so likely affords productive dialogues. The implications of addressivity in teaching and learning are further discussed.

  3. Synthesis of Fault-Tolerant Embedded Systems

    DEFF Research Database (Denmark)

    Eles, Petru; Izosimov, Viacheslav; Pop, Paul

    2008-01-01

    This work addresses the issue of design optimization for fault- tolerant hard real-time systems. In particular, our focus is on the handling of transient faults using both checkpointing with rollback recovery and active replication. Fault tolerant schedules are generated based on a conditional...... process graph representation. The formulated system synthesis approaches decide the assignment of fault-tolerance policies to processes, the optimal placement of checkpoints and the mapping of processes to processors, such that multiple transient faults are tolerated, transparency requirements...

  4. Tolerability of hypertonic injectables.

    Science.gov (United States)

    Wang, Wei

    2015-07-25

    Injectable drug products are ideally developed as isotonic solutions. Often, hypertonic injectables may have to be marketed for a variety of reasons such as product solubilization and stabilization. A key concern during product formulation development is the local and systemic tolerability of hypertonic products upon injection. This report reviews and discusses the tolerability in terms of local discomfort, irritation, sensation of heat and pain, along with other observed side effects of hypertonicity in both in-vitro systems and in-vivo animal and human models. These side effects clearly depend on the degree of hypertonicity. The sensation of pain among different injection routes seems to follow this order: intramuscular>subcutaneous>intravenous or intravascular. It is recommended that the upper osmolality limit should be generally controlled under 600 mOsm/kg for drug products intended for intramuscular or subcutaneous injection. For drug products intended for intravenous or intravascular injection, the recommended upper limit should be generally controlled under 1,000 mOsm/kg for small-volume injections (≤ 100 mL) and 500 mOsm/kg for large-volume injections (>100mL). Several options are available for minimization of hypertonicity-induced pain upon product administration. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Effects of Starvation and Thermal Stress on the Thermal Tolerance of Silkworm, Bombyx mori: Existence of Trade-offs and Cross-Tolerances.

    Science.gov (United States)

    Mir, A H; Qamar, A

    2017-09-27

    Organisms, in nature, are often subjected to multiple stressors, both biotic and abiotic. Temperature and starvation are among the main stressors experienced by organisms in their developmental cycle and the responses to these stressors may share signaling pathways, which affects the way these responses are manifested. Temperature is a major factor governing the performance of ectothermic organisms in ecosystems worldwide and, therefore, the thermal tolerance is a central issue in the thermobiology of these organisms. Here, we investigated the effects of starvation as well as mild heat and cold shocks on the thermal tolerance of the larvae of silkworm, Bombyx mori (Linnaeus). Starvation acted as a meaningful or positive stressor as it improved cold tolerance, measured as chill coma recovery time (CCRT), but, at the same time, it acted as a negative stressor and impaired the heat tolerance, measured as heat knockdown time (HKT). In the case of heat tolerance, starvation negated the positive effects of both mild cold as well as mild heat shocks and thus indicated the existence of trade-off between these stressors. Both mild heat and cold shocks improved the thermal tolerance, but the effects were more prominent when the indices were measured in response to a stressor of same type, i.e., a mild cold shock improved the cold tolerance more than the heat tolerance and vice versa. This improvement in thermal tolerance by both mild heat as well as cold shocks indicated the possibility of cross-tolerance between these stressors.

  6. Addressing Sexual Harassment

    Science.gov (United States)

    Young, Ellie L.; Ashbaker, Betty Y.

    2008-01-01

    This article discusses ways on how to address the problem of sexual harassment in schools. Sexual harassment--simply defined as any unwanted and unwelcome sexual behavior--is a sensitive topic. Merely providing students, parents, and staff members with information about the school's sexual harassment policy is insufficient; schools must take…

  7. Addressing Social Issues.

    Science.gov (United States)

    Schoebel, Susan

    1991-01-01

    Maintains that advertising can help people become more aware of social responsibilities. Describes a successful nationwide newspaper advertising competition for college students in which ads address social issues such as literacy, drugs, teen suicide, and teen pregnancy. Notes how the ads have helped grassroots programs throughout the United…

  8. Sesotho Address Forms

    Directory of Open Access Journals (Sweden)

    Akindele, Dele Femi

    2008-01-01

    Full Text Available Address forms constitute an integral part of Basotho sociolinguistic etiquette. They are regarded as a kind of emotional capital that may be invested in putting others at ease. They are indicators of deference, politeness and markers of social distance. (Fasold 1990, Akindele 1990, 1991, 1993 This paper examines the address forms used by the Basotho people. It analyzes and discusses the various types and the factors determining their use. The discussion of address forms in Sesotho focuses on First Name, Title plus First Name, Title plus Last Name, Nickname, Multiple Names, and Teknonym. Drawing data from semi-literate and literate urban and rural population of Maseru district of Lesotho, it was found that the commonest form of address used by the Basotho people is title plus first name. e.g. ntate Thabo (father Thabo, 'm'e Puleng (mother Puleng, ausi Maneo (sister Maneo, abuti Mahao (brother Mahao. It is used by close relations, associates, and familiar people in both formal and informal situations.

  9. Addressivity in Cogenerative Dialogues

    Science.gov (United States)

    Hsu, Pei-Ling

    2014-01-01

    Ashraf Shady's paper provides a first-hand reflection on how a foreign teacher used cogens as culturally adaptive pedagogy to address cultural misalignments with students. In this paper, Shady drew on several cogen sessions to showcase his journey of using different forms of cogens with his students. To improve the quality of cogens, one…

  10. Psychological Stability of a Personality and Capability of Tolerant Interaction as Diverse Manifestations of Tolerance

    Science.gov (United States)

    Belasheva, Irina Valeryevna; Petrova, Nina Fedorovna

    2016-01-01

    Present article addresses studying tolerance as a factor of personality stability, which manifests on the level of interpersonal relationships and on the level of intra-personal system of stressors resistance. The article includes theoretical analysis of the tolerance construct as an integrative personality formation. It explores the question of…

  11. Convective heat transfer

    CERN Document Server

    Kakac, Sadik; Pramuanjaroenkij, Anchasa

    2014-01-01

    Intended for readers who have taken a basic heat transfer course and have a basic knowledge of thermodynamics, heat transfer, fluid mechanics, and differential equations, Convective Heat Transfer, Third Edition provides an overview of phenomenological convective heat transfer. This book combines applications of engineering with the basic concepts of convection. It offers a clear and balanced presentation of essential topics using both traditional and numerical methods. The text addresses emerging science and technology matters, and highlights biomedical applications and energy technologies. What’s New in the Third Edition: Includes updated chapters and two new chapters on heat transfer in microchannels and heat transfer with nanofluids Expands problem sets and introduces new correlations and solved examples Provides more coverage of numerical/computer methods The third edition details the new research areas of heat transfer in microchannels and the enhancement of convective heat transfer with nanofluids....

  12. Heat intolerance: predisposing factor or residual injury?

    Science.gov (United States)

    Epstein, Y

    1990-02-01

    Great individual variability exists in the ability to sustain heat stress. Some individuals are more susceptible to heat than others. Those individuals, among the young active population (athletes, military recruits, laborers), are at risk to contract exertional heat stroke. Low tolerance to heat results from either functional factors, or from congenital or acquired disturbances. In most cases heat intolerance can be foreseen. Cases of dehydration, overweight, low physical fitness, lack of acclimatization, febrile or infectious diseases, and skin disorders should be regarded a priori as predisposing factors for heat intolerance. Special attention should be paid to subjects with previous heat stroke episodes since it might reflect an underlying cause for heat susceptibility. The heat tolerance of these subjects should be tested 8-12 wk postepisode to detect a possible residual injury in the ability to thermoregulate adequately in the heat.

  13. Generating high temperature tolerant transgenic plants: Achievements and challenges.

    Science.gov (United States)

    Grover, Anil; Mittal, Dheeraj; Negi, Manisha; Lavania, Dhruv

    2013-05-01

    Production of plants tolerant to high temperature stress is of immense significance in the light of global warming and climate change. Plant cells respond to high temperature stress by re-programming their genetic machinery for survival and reproduction. High temperature tolerance in transgenic plants has largely been achieved either by over-expressing heat shock protein genes or by altering levels of heat shock factors that regulate expression of heat shock and non-heat shock genes. Apart from heat shock factors, over-expression of other trans-acting factors like DREB2A, bZIP28 and WRKY proteins has proven useful in imparting high temperature tolerance. Besides these, elevating the genetic levels of proteins involved in osmotic adjustment, reactive oxygen species removal, saturation of membrane-associated lipids, photosynthetic reactions, production of polyamines and protein biosynthesis process have yielded positive results in equipping transgenic plants with high temperature tolerance. Cyclic nucleotide gated calcium channel proteins that regulate calcium influxes across the cell membrane have recently been shown to be the key players in induction of high temperature tolerance. The involvement of calmodulins and kinases in activation of heat shock factors has been implicated as an important event in governing high temperature tolerance. Unfilled gaps limiting the production of high temperature tolerant transgenic plants for field level cultivation are discussed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  14. Estimating heat-to-heat variation from a statistician's point of view

    International Nuclear Information System (INIS)

    Hebble, T.L.

    1976-01-01

    Heat-to-heat variability is the change in results that occurs when the same tests under the same conditions are applied to samples from different heats of the same material. Heat-to-heat variability reflects, among other things, difference in chemistry and in processing history. Published Japanese tensile and creep tests on types 304 and 316 stainless steel tube are used to illustrate the analysis of variance technique as a tool for isolating heat-to-heat variation. The importance of the underlying model and the role of replication are indicated. Finally, confidence intervals and tolerance limits are computed from numerical estimates of heat-to-heat variation. 17 tables

  15. Tolerance Optimization for Mechanisms with Lubricated Joints

    International Nuclear Information System (INIS)

    Choi, J.-H.; Lee, S.J.; Choi, D.-H.

    1998-01-01

    This paper addresses an analytical approach to tolerance optimization for planar mechanisms with lubricated joints based on mechanical error analysis. The mobility method is applied to consider the lubrication effects at joints and planar mechanisms are stochastically defined by using the clearance vector model for mechanical error analysis. The uncertainties considered in the analysis are tolerances on link lengths and radial clearances and these are selected as design variables. To show the validity of the proposed method for mechanical error analysis, it is applied to two examples, and the results obtained are compared with those of Monte Carlo simulations. Based on the mechanical error analysis, tolerance optimizations are applied to the examples

  16. Heat Islands

    Science.gov (United States)

    EPA's Heat Island Effect Site provides information on heat islands, their impacts, mitigation strategies, related research, a directory of heat island reduction initiatives in U.S. communities, and EPA's Heat Island Reduction Program.

  17. District heating

    International Nuclear Information System (INIS)

    1989-03-01

    The papers presented at this meeting dealt with an international comparison of district heating, the Swiss district heating network, political aspects of nuclear district heating, nuclear and non-nuclear sources for district heating. 17 figs., 6 tabs

  18. Teaching Tolerance? Associational Diversity and Tolerance Formation

    DEFF Research Database (Denmark)

    Rapp, Carolin; Freitag, Markus

    2015-01-01

    Tolerance is a basic democratic principle that helps civil societies cope with rising levels of diversity stemming from increased immigration and individualism. During the last decade the question of how tolerance may be fostered has dominated debates in public and academic spheres. In this article...

  19. Seleção de linhagens com tolerância ao calor em germoplasma de tomateiro coletado na região Norte do Brasil Selection of heat tolerant tomato inbred lines from landraces adapted for cultivation in the North Region of Brazil

    Directory of Open Access Journals (Sweden)

    Leonardo de B. Giordano

    2005-03-01

    Full Text Available As altas temperaturas nas regiões tropicais e equatoriais induzem uma série de distúrbios morfológicos e/ou fisiológicos em estruturas florais do tomateiro, resultando em menor produtividade devido a maiores taxas de abortamento e má formação de frutos. Neste trabalho foram avaliadas linhagens de tomateiro oriundas de duas populações que vêm sendo cultivadas em Roraima, região Norte do Brasil. Doze linhagens foram obtidas após um ciclo prévio de seleção (em Brasília-DF em condições de temperatura elevada. A avaliação destas doze linhagens e duas cultivares testemunhas ('Viradoro' e 'Santa Clara' foi conduzida em casa de vegetação com temperaturas média das mínimas de 15ºC e média das máximas de 46,2ºC. Foram observadas diferenças significativas para número de frutos abortados, número de frutos maduros, peso de frutos maduros, teores de sólidos solúveis, firmeza e coloração de frutos. As linhagens (como um grupo apresentaram melhor desempenho do que as testemunhas 'Viradoro' e 'Santa Clara' para os parâmetros número de frutos abortados, peso, número e coloração de frutos maduros. A metodologia adotada no presente trabalho, permite a identificação de genótipos superiores adaptados ao cultivo em regiões tropicais e equatoriais com elevadas temperaturas.Heat tolerance is a major trait for tomato breeding programs targeted for lowland wet climates in equatorial and tropical areas of the world. High temperatures might cause several disturbances to morphological and physiological characteristics of the tomato flowers leading to yield constraints due to reduction in fruit setting. In the present work, an experiment was conducted to evaluate tomato breeding lines, derived from two tomato landrace populations cultivated by farmers in Roraima State (North Region of Brazil. Twelve inbred lines were obtained from these populations after one cycle of selection in a plastic house with high temperatures. These 12

  20. Counting addressing method: Command addressable element and extinguishing module

    Directory of Open Access Journals (Sweden)

    Ristić Jovan D.

    2009-01-01

    Full Text Available The specific requirements that appear in addressable fire detection and alarm systems and the shortcomings of the existing addressing methods were discussed. A new method of addressing of detectors was proposed. The basic principles of addressing and responding of a called element are stated. Extinguishing module is specific subsystem in classic fire detection and alarm systems. Appearing of addressable fire detection and alarm systems didn't caused essential change in the concept of extinguishing module because of long calling period of such systems. Addressable fire security system based on counting addressing method reaches high calling rates and enables integrating of the extinguishing module in addressable system. Solutions for command addressable element and integrated extinguishing module are given in this paper. The counting addressing method was developed for specific requirements in fire detection and alarm systems, yet its speed and reliability justifies its use in the acquisition of data on slowly variable parameters under industrial conditions. .

  1. Accident tolerant composite nuclear fuels

    Directory of Open Access Journals (Sweden)

    Szpunar Barbara

    2017-01-01

    Full Text Available Investigated accident tolerant nuclear fuels are fuels with enhanced thermal conductivity, which can withstand the loss of coolant for a longer time by allowing faster dissipation of heat, thus lowering the centerline temperature and preventing the melting of the fuel. Traditional nuclear fuels have a very low thermal conductivity and can be significantly enhanced if transformed into a composite with a very high thermal conductivity components. In this study, we analyze the thermal properties of various composites of mixed oxides and thoria fuels to improve thermal conductivity for the next generation safer nuclear reactors.

  2. Light addressable gold electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Waqas

    2011-07-01

    The main objective carried out in this dissertation was to fabricate Light Amplified Potentiometric sensors (LAPS) based upon the semiconductor nanoparticles (quantum dots) instead of its bulk form. Quantum dots (QDs) were opted for this device fabrication because of their superior fluorescent, electric and catalytic properties. Also in comparison to their bulk counterparts they will make device small, light weighted and power consumption is much lower. QDs were immobilized on a Au substrate via 1,4 benzene dithiol (BDT) molecule. Initially a self-assembled monolayer (SAM) of BDT was established on Au substrate. Because of SAM, the conductivity of Au substrate decreased dramatically. Furthermore QDs were anchored with the help of BDT molecule on Au substrate. When QDs immobilized on Au substrate (QD/Au) via BDT molecule were irradiated with UV-visible light, electron-hole pairs were generated in QDs. The surface defect states in QDs trapped the excited electrons and long lived electron-hole pairs were formed. By the application of an appropriate bias potential on Au substrate the electrons could be supplied or extracted from the QDs via tunneling through BDT. Thus a cathodic or anodic current could be observed depending upon bias potential under illumination. However without light illumination the QD/Au electrode remained an insulator. To improve the device different modifications were made, including different substrates (Au evaporated on glass, Au evaporated on mica sheets and Au sputtered on SiO{sub 2}/Si) and different dithiol molecules (capped and uncapped biphenyl 4,4' dithiol and capped and uncapped 4,4' dimercaptostilbenes) were tried. Also different QD immobilization techniques (normal incubation, spin coating, layer by layer assembly (LbL) of polyelectrolytes and heat immobilization) were employed. This device was able to detect electrochemically different analytes depending upon the QDs incorporated. For example CdS QDs were able to detect 4

  3. Lactose tolerance tests

    Science.gov (United States)

    Hydrogen breath test for lactose tolerance ... Two common methods include: Lactose tolerance blood test Hydrogen breath test The hydrogen breath test is the preferred method. It measures the amount of hydrogen ...

  4. District heating

    International Nuclear Information System (INIS)

    2005-01-01

    By request of the Dutch Lower House the Netherlands Court of Audit examined the profitability or loss-making of district heating projects between 2001 and 2003. District heating supplies heat to consumers for heating their houses and providing warm tap water. The heat is supplied via warm water that runs through a network of pipes. In the Netherlands, about 250,000 households use district heating. The request by the Dutch Lower House to conduct research on district heating coheres with the initiative District Heating Bill. The bill aims to legally guarantee the supply and affordability of heat for consumers of district heating. [mk] [nl

  5. Immunologic changes in children with egg allergy ingesting extensively heated egg.

    Science.gov (United States)

    Lemon-Mulé, Heather; Sampson, Hugh A; Sicherer, Scott H; Shreffler, Wayne G; Noone, Sally; Nowak-Wegrzyn, Anna

    2008-11-01

    Prior studies have suggested that heated egg might be tolerated by some children with egg allergy. We sought to confirm tolerance of heated egg in a subset of children with egg allergy, to evaluate clinical and immunologic predictors of heated egg tolerance, to characterize immunologic changes associated with continued ingestion of heated egg, and to determine whether a diet incorporating heated egg is well tolerated. Subjects with documented IgE-mediated egg allergy underwent physician-supervised oral food challenges to extensively heated egg (in the form of a muffin and a waffle), with tolerant subjects also undergoing regular egg challenges (in a form of scrambled egg or French toast). Heated egg-tolerant subjects incorporated heated egg into their diets. Skin prick test wheal diameters and egg white, ovalbumin, and ovomucoid IgE levels, as well as ovalbumin and ovomucoid IgG4 levels, were measured at baseline for all subjects and at 3, 6, and 12 months for those tolerant of heated egg. Sixty-four of 117 subjects tolerated heated egg, 23 tolerated regular egg, and 27 reacted to heated egg. Heated egg-reactive subjects had larger skin test wheals and greater egg white-specific, ovalbumin-specific, and ovomucoid-specific IgE levels compared with heated egg- and egg-tolerant subjects. Continued ingestion of heated egg was associated with decreased skin test wheal diameters and ovalbumin-specific IgE levels and increased ovalbumin-specific and ovomucoid-specific IgG4 levels. The majority of subjects with egg allergy were tolerant of heated egg. Continued ingestion of heated egg was well tolerated and associated with immunologic changes that paralleled the changes observed with the development of clinical tolerance to regular egg.

  6. Recognition and Toleration

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2010-01-01

    Recognition and toleration are ways of relating to the diversity characteristic of multicultural societies. The article concerns the possible meanings of toleration and recognition, and the conflict that is often claimed to exist between these two approaches to diversity. Different forms...... or interpretations of recognition and toleration are considered, confusing and problematic uses of the terms are noted, and the compatibility of toleration and recognition is discussed. The article argues that there is a range of legitimate and importantly different conceptions of both toleration and recognition...

  7. Fault Tolerant Feedback Control

    DEFF Research Database (Denmark)

    Stoustrup, Jakob; Niemann, H.

    2001-01-01

    An architecture for fault tolerant feedback controllers based on the Youla parameterization is suggested. It is shown that the Youla parameterization will give a residual vector directly in connection with the fault diagnosis part of the fault tolerant feedback controller. It turns out...... that there is a separation be-tween the feedback controller and the fault tolerant part. The closed loop feedback properties are handled by the nominal feedback controller and the fault tolerant part is handled by the design of the Youla parameter. The design of the fault tolerant part will not affect the design...

  8. Identifying potential molecular factors involved in Bacillus amyloliquefaciens 5113 mediated abiotic stress tolerance in wheat.

    Science.gov (United States)

    Abd El-Daim, I A; Bejai, S; Fridborg, I; Meijer, J

    2018-03-01

    Abiotic stressors are main limiting factors for agricultural production around the world. Plant growth-promoting bacteria have been successfully used to improve abiotic stress tolerance in several crops including wheat. However, the molecular changes involved in the improvement of stress management are poorly understood. The present investigation addressed some molecular factors involved in bacterially induced plant abiotic stress responses by identifying differentially expressed genes in wheat (Triticum aestivum) seedlings treated with the beneficial bacterium Bacillus amyloliquefaciens subsp. plantarum UCMB5113 prior to challenge with abiotic stress conditions such as heat, cold or drought. cDNA-AFLP analysis revealed differential expression of more than 200 transcript-derived fragments (TDFs) in wheat leaves. Expression of selected TDFs was confirmed using RT-PCR. DNA sequencing of 31 differentially expressed TDFs revealed significant homology with both known and unknown genes in database searches. Virus-induced gene silencing of two abscisic acid-related TDFs showed different effects upon heat and drought stress. We conclude that treatment with B. amyloliquefaciens 5113 caused molecular modifications in wheat in order to induce tolerance against heat, cold and drought stress. Bacillus treatment provides systemic effects that involve metabolic and regulatory functions supporting both growth and stress management. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  9. Optimization of Heat Exchangers

    International Nuclear Information System (INIS)

    Catton, Ivan

    2010-01-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics (pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger design.

  10. Optimization of Heat Exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Ivan Catton

    2010-10-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  11. Mechanical tolerance stackup and analysis

    CERN Document Server

    Fischer, Bryan R

    2004-01-01

    BackgroundDimensioning and TolerancingTolerance Format and Decimal PlacesConverting Plus/Minus Dimensions and Tolerances into Equal Bilaterally Toleranced DimensionsVariation and Sources of VariationTolerance AnalysisWorst-case Tolerance StackupsStatistical Tolerance StackupsGeometric Dimensioning and Tolerancing (GD&T)Converting Plus/Minus Tolerancing to Positional Tolerancing and Projected Tolerance ZonesDiametral and Radial Tolerance StackupsSpecifying Material Condition Modifiers and Their Effect on Tolerance Stackups The Tolerance Stackup SketchThe Tolerance Stackup Report FormTolerance S

  12. Heat Stress

    Science.gov (United States)

    ... Publications and Products Programs Contact NIOSH NIOSH HEAT STRESS Recommend on Facebook Tweet Share Compartir NEW OSHA- ... hot environments may be at risk of heat stress. Exposure to extreme heat can result in occupational ...

  13. Regulatory focus affects physician risk tolerance.

    Science.gov (United States)

    Veazie, Peter J; McIntosh, Scott; Chapman, Benjamin P; Dolan, James G

    2014-01-01

    Risk tolerance is a source of variation in physician decision-making. This variation, if independent of clinical concerns, can result in mistaken utilization of health services. To address such problems, it will be helpful to identify nonclinical factors of risk tolerance, particularly those amendable to intervention-regulatory focus theory suggests such a factor. This study tested whether regulatory focus affects risk tolerance among primary care physicians. Twenty-seven primary care physicians were assigned to promotion-focused or prevention-focused manipulations and compared on the Risk Taking Attitudes in Medical Decision Making scale using a randomization test. Results provide evidence that physicians assigned to the promotion-focus manipulation adopted an attitude of greater risk tolerance than the physicians assigned to the prevention-focused manipulation (p = 0.01). The Cohen's d statistic was conventionally large at 0.92. Results imply that situational regulatory focus in primary care physicians affects risk tolerance and may thereby be a nonclinical source of practice variation. Results also provide marginal evidence that chronic regulatory focus is associated with risk tolerance (p = 0.05), but the mechanism remains unclear. Research and intervention targeting physician risk tolerance may benefit by considering situational regulatory focus as an explanatory factor.

  14. China : Development of National Heat Pricing and Billing Policy

    OpenAIRE

    Meyer, Anke Sofia; Kalkum, Bernd

    2008-01-01

    Market-based reforms in China's urban centralized heating sector are essential to addressing the perpetual inefficiency of a sector built on welfare based principles. The reform of heat pricing and billing is a crucial part of overall heat reform, since it will commodity heat and thus create economic incentives to provide and use heat much more efficiently. Heat pricing and billing reform ...

  15. Children, Hyperactivity and Low Frustration Tolerance.

    Science.gov (United States)

    Shaughnessy, Michael F.; Scott, Patricia Carol

    This paper addresses issues regarding the hyperactive child, the impulsive child, and the low frustration tolerance child. It points out the subjectivity involved in identifying children as hyperactive, and outlines various forms of hyperactivity: the child who is in constant movement, the child who manages control in school but exhibits whirlwind…

  16. Modelling Accident Tolerant Fuel Concepts

    Energy Technology Data Exchange (ETDEWEB)

    Hales, Jason Dean [Idaho National Laboratory; Gamble, Kyle Allan Lawrence [Idaho National Laboratory

    2016-05-01

    The catastrophic events that occurred at the Fukushima-Daiichi nuclear power plant in 2011 have led to widespread interest in research of alternative fuels and claddings that are proposed to be accident tolerant. The United States Department of Energy (DOE) through its Nuclear Energy Advanced Modeling and Simulation (NEAMS) program has funded an Accident Tolerant Fuel (ATF) High Impact Problem (HIP). The ATF HIP is a three-year project to perform research on two accident tolerant concepts. The final outcome of the ATF HIP will be an in-depth report to the DOE Advanced Fuels Campaign (AFC) giving a recommendation on whether either of the two concepts should be included in their lead test assembly scheduled for placement into a commercial reactor in 2022. The two ATF concepts under investigation in the HIP are uranium silicide fuel and iron-chromium-aluminum (FeCrAl) alloy cladding. Utilizing the expertise of three national laboratory participants (Idaho National Laboratory, Los Alamos National Laboratory, and Argonne National Laboratory), a comprehensive multiscale approach to modeling is being used that includes atomistic modeling, molecular dynamics, rate theory, phase-field, and fuel performance simulations. Model development and fuel performance analysis are critical since a full suite of experimental studies will not be complete before AFC must prioritize concepts for focused development. In this paper, we present simulations of the two proposed accident tolerance fuel systems: U3Si2 fuel with Zircaloy-4 cladding, and UO2 fuel with FeCrAl cladding. Sensitivity analyses are completed using Sandia National Laboratories’ Dakota software to determine which input parameters (e.g., fuel specific heat) have the greatest influence on the output metrics of interest (e.g., fuel centerline temperature). We also outline the multiscale modelling approach being employed. Considerable additional work is required prior to preparing the recommendation report for the Advanced

  17. Politicas de tolerancia cero (Zero Tolerance Policies). ERIC Digest.

    Science.gov (United States)

    McAndrews, Tobin

    State legislatures and school boards are adopting a growing number of zero-tolerance polices toward weapons, guns, and violence. Zero-tolerance polices are rules intended to address specific school-safety issues. They have arisen in part as a response to the threat of the withdrawal of federal funds under the 1994 Gun-Free Schools Act, and…

  18. Medical screening and evaluation for heat stress

    International Nuclear Information System (INIS)

    Kenney, L.W.

    1985-01-01

    Wide interindividual variation exists with respect to heat tolerance, making it difficult to predict individual responses. However, several general physical and physiological characteristics are associated with excessive strain and early exhaustion during work in the heat. Included among these correlates of heat intolerance are a medical history of heat illness, acclimation state, age, body composition and size, aerobic fitness level, hypertension, and drug and alcohol use. The approach of choice for medical evaluation for heat exposure is a two-stage evaluation. First, the examining physician should be encouraged to screen out those workers whose characteristics increase their risk of heat intolerance. Secondly, a short exercise test is proposed which accurately predicts relative heat tolerance across a working population. This test is recommended as an adjunct screening test at the examining physician's disgression

  19. Ventilation with heat recovery

    DEFF Research Database (Denmark)

    Tommerup, Henrik M.; Svendsen, Svend

    2005-01-01

    This paper presents the experiences from the use of ventilation with heat recovery in several experimental single-family houses developed and built within the last four years to meet the new Danish energy requirements of 2005. Included are descriptions of the ventilation system components...... and the main functional demands as well as measurements of the thermal efficiency, electricity consumptions and building air tightness. The paper addresses the aspects of minimizing the heat loss from the duct system and the heat recovery unit (when placed in an unheated attic space) in order to obtain...

  20. Antimicrobial Tolerance in Biofilms

    OpenAIRE

    Stewart, Philip S.

    2015-01-01

    The tolerance of microorganisms in biofilms to antimicrobial agents is examined through a meta-analysis of literature data. A numerical tolerance factor comparing the rates of killing in the planktonic and biofilm states is defined to provide a quantitative basis for the analysis. Tolerance factors for biocides and antibiotics range over three orders of magnitude. This variation is not explained by taking into account the molecular weight of the agent, the chemistry of the agent, the substrat...

  1. Novel Method for Measuring the Heat Collection Rate and Heat Loss Coefficient of Water-in-Glass Evacuated Tube Solar Water Heaters Based on Artificial Neural Networks and Support Vector Machine

    Directory of Open Access Journals (Sweden)

    Zhijian Liu

    2015-08-01

    Full Text Available The determinations of heat collection rate and heat loss coefficient are crucial for the evaluation of in service water-in-glass evacuated tube solar water heaters. However, the direct determination requires complex detection devices and a series of standard experiments, which also wastes too much time and manpower. To address this problem, we propose machine learning models including artificial neural networks (ANNs and support vector machines (SVM to predict the heat collection rate and heat loss coefficient without a direct determination. Parameters that can be easily obtained by “portable test instruments” were set as independent variables, including tube length, number of tubes, tube center distance, heat water mass in tank, collector area, final temperature and angle between tubes and ground, while the heat collection rate and heat loss coefficient determined by the detection device were set as dependent variables respectively. Nine hundred fifteen samples from in-service water-in-glass evacuated tube solar water heaters were used for training and testing the models. Results show that the multilayer feed-forward neural network (MLFN with 3 nodes is the best model for the prediction of heat collection rate and the general regression neural network (GRNN is the best model for the prediction of heat loss coefficient due to their low root mean square (RMS errors, short training times, and high prediction accuracies (under the tolerances of 30%, 20%, and 10%, respectively.

  2. Heat pumps

    CERN Document Server

    Macmichael, DBA

    1988-01-01

    A fully revised and extended account of the design, manufacture and use of heat pumps in both industrial and domestic applications. Topics covered include a detailed description of the various heat pump cycles, the components of a heat pump system - drive, compressor, heat exchangers etc., and the more practical considerations to be taken into account in their selection.

  3. Port virtual addressing for PC

    International Nuclear Information System (INIS)

    Bolanos, L.; Arista, E.; Osorio Deliz, J.F.

    1997-01-01

    Instruments for nuclear signal measurements based on add-on card for a personal computer (PC) are designed often. Then one faces the problem of the addressing of data input/output devices which show an integration level or intelligence that makes the use of several port address indispensable, and these are limited in the PC. The virtual addressing offers the advantage of the occupation of few addresses to accede to many of these devices. The principles of this technique and the appliances of a solution in radiometric in a radiometric card based on programmed logic are discussed in this paper

  4. Reclaiming unused IPv4 addresses

    CERN Multimedia

    IT Department

    2016-01-01

    As many people might know, the number of IPv4 addresses is limited and almost all have been allocated (see here and here for more information).   Although CERN has been allocated some 340,000 addresses, the way these are allocated across the site is not as efficient as we would like. As we face an increasing demand for IPv4 addresses with the growth in virtual machines, the IT Department’s Communication Systems Group will be reorganising address allocation during 2016 to make more efficient use of the IPv4 address ranges that have been allocated to CERN. We aim, wherever possible, to avoid giving out fixed IP addresses, and have all devices connected to the campus network obtain an address dynamically each time they connect. As a first stage, starting in February, IP addresses that have not been used for more than 9 months will be reclaimed. No information about the devices concerned will be deleted from LANDB, but a new IP address will have to be requested if they are ever reconnected to t...

  5. Compromise and Toleration

    DEFF Research Database (Denmark)

    Rostbøll, Christian F.

    Political compromise is akin to toleration, since both consist of an "agreement to disagree." Compromise and toleration also share a predicament of being regarded as ambiguous virtues that require of us to accept something we actually regard as wrong. However, we misunderstand the nature, justifi......Political compromise is akin to toleration, since both consist of an "agreement to disagree." Compromise and toleration also share a predicament of being regarded as ambiguous virtues that require of us to accept something we actually regard as wrong. However, we misunderstand the nature......, justification, and limits of compromise if we see it merely as a matter of toleration. While toleration is mainly a matter of accepting citizens' equal right to co-existence as subjects to law, political compromise includes the parties in making law – it makes them co-authors of law. Toleration entails....... The justification of compromise goes beyond, even if it includes, respect for each individual's right to determine her own conception of the good to an idea of respect for citizens as co-legislators. Second, the limits of compromise are not the same as the limits of toleration. The conditions for being included...

  6. Fault tolerant computing systems

    International Nuclear Information System (INIS)

    Randell, B.

    1981-01-01

    Fault tolerance involves the provision of strategies for error detection damage assessment, fault treatment and error recovery. A survey is given of the different sorts of strategies used in highly reliable computing systems, together with an outline of recent research on the problems of providing fault tolerance in parallel and distributed computing systems. (orig.)

  7. The Paradoxes of Tolerance

    Science.gov (United States)

    Pasamonik, Barbara

    2004-01-01

    Teachers who endeavor to build tolerant attitudes in their students often fall into the trap of political correctness. Political correctness can suspend free reflection on the differences inherent in otherness, which is the subject of tolerance, and creates an ideology of the generalized, abstract Other. As a result, teachers prefer to talk about…

  8. Remember Tolerance Differently

    DEFF Research Database (Denmark)

    Tønder, Lars

    2012-01-01

    This essay questions the linear conception of history which often accompanies the way contemporary democratic theory tends to disavow tolerance's discontinuities and remainders. In the spirit of Foucault's genealogy of descent, the idea is to develop a new sense of tolerance's history, not by inv...

  9. Osmotic stress tolerance in semi-terrestrial tardigrades

    DEFF Research Database (Denmark)

    Heidemann, Nanna W T; Smith, Daniel K.; Hygum, Thomas L.

    2016-01-01

    Little is known about ionic and osmotic stress tolerance in tardigrades. Here, we examine salt stress tolerance in Ramazzottius oberhaeuseri and Echiniscus testudo from Nivå (Denmark) and address whether limno-terrestrial tardigrades can enter a state of quiescence (osmobiosis) in the face of hig...... that the limno-terrestrial R. oberhaeuseri enters a state of quiescence in the face of high external osmotic pressure and that it, in this state, is highly tolerant of ionic and osmotic stress.......Little is known about ionic and osmotic stress tolerance in tardigrades. Here, we examine salt stress tolerance in Ramazzottius oberhaeuseri and Echiniscus testudo from Nivå (Denmark) and address whether limno-terrestrial tardigrades can enter a state of quiescence (osmobiosis) in the face of high...

  10. Heat pumps

    CERN Document Server

    Brodowicz, Kazimierz; Wyszynski, M L; Wyszynski

    2013-01-01

    Heat pumps and related technology are in widespread use in industrial processes and installations. This book presents a unified, comprehensive and systematic treatment of the design and operation of both compression and sorption heat pumps. Heat pump thermodynamics, the choice of working fluid and the characteristics of low temperature heat sources and their application to heat pumps are covered in detail.Economic aspects are discussed and the extensive use of the exergy concept in evaluating performance of heat pumps is a unique feature of the book. The thermodynamic and chemical properties o

  11. Advances in heat transfer enhancement

    CERN Document Server

    Saha, Sujoy Kumar; Sundén, Bengt; Wu, Zan

    2016-01-01

    This Brief addresses the phenomena of heat transfer enhancement. A companion edition in the SpringerBrief Subseries on Thermal Engineering and Applied Science to three other monographs including “Critical Heat Flux in Flow Boiling in Microchannels,” this volume is idea for professionals, researchers, and graduate students concerned with electronic cooling.

  12. District heating versus local heating - Social supportability

    International Nuclear Information System (INIS)

    Matei, Magdalena; Enescu, Diana; Varjoghie, Elena; Radu, Florin; Matei, Lucian

    2004-01-01

    District heating, DH, is an energy source which can provide a cost-effective, environmentally friendly source of heat and power for cities, but only in the case of well running systems, with reasonable technological losses. The benefits of DH system are well known: environmental friendly, energy security, economic and social advantages. DH already covers 60% of heating and hot water needs in transition economies. Today, 70 % of Russian, Latvian and Belarus homes use DH, and heating accounts for one-third of total Russian energy consumption. Yet a large number of DH systems in the region face serious financial, marketing or technical problems because of the policy framework. How can DH issues be best addressed in national and local policy? What can governments do to create the right conditions for the sustainable development of DH while improving service quality? What policies can help capture the economic, environmental and energy security benefits of co-generation and DH? To address these questions, the International Energy Agency (IEA) hosted in 2002 and 2004 conference focusing on the crucial importance of well-designed DH policies, for exchanging information on policy approaches. The conclusions of the conference have shown that 'DH systems can do much to save energy and boost energy security, but stronger policy measures are needed to encourage wise management and investment. With a stronger policy framework, DH systems in formerly socialist countries could save the equivalent of 80 billion cubic meters of natural gas a year through supply side efficiency improvements. This is greater than total annual natural gas consumption in Italy'. More efficient systems will also decrease costs, reducing household bills and making DH competitive on long-term. This paper presents the issues: -Theoretical benefits of the district heating and cooling systems; - Municipal heating in Romania; - Technical and economic problems of DH systems and social supportability; - How

  13. Tolerance to high temperature extremes in an invasive lace bug, Corythucha ciliata (Hemiptera: Tingidae, in subtropical China.

    Directory of Open Access Journals (Sweden)

    Rui-Ting Ju

    Full Text Available Biological invasions are predicted to be more frequent as climate change is increasing its positive impact on the prevalence of invasive exotic species. Success of insect invaders in different temperature zones is closely related to their tolerance to temperature extremes. In this study, we used an exotic lace bug (Corythucha ciliata as the study organism to address the hypotheses that an insect species invading a subtropical zone from temperate regions has a high capacity to survive and adapt to high temperatures, and that its thermal tolerance plays an important role in determining its seasonal abundance and geographic distribution. To test these hypotheses, the effects of heat shock on the survival and reproduction of C. ciliata adults were assessed in the laboratory. Adults were exposed to 26 (control, 35, 37, 39, 41, 43, and 45°C for 2 h, and then were transferred to 26°C. Heat-shock temperatures ranging from 35 to 41°C did not significantly affect survival pattern, longevity, and fecundity of adults, but heat shock at 43 and 45°C significantly reduced these traits. Exposing parent females to heat-shock treatments from 35 to 41°C did not significantly affect the hatching rate of their eggs, survival of the nymphs, and the proportion of female F(1 progeny, while no progeny were produced with treatments of 43 and 45°C. The results indicate that C. ciliata can tolerate high temperatures less than 41°C, which may contribute to its expansion into the lower latitudes in China where its hosts (Platanus trees are widely planted. Our findings have important implications for predicting seasonal abundance and understanding invasion mechanisms of this important urban invader under climate change.

  14. HEAT RECUPERATION

    Directory of Open Access Journals (Sweden)

    S. L. Rovin

    2011-01-01

    Full Text Available Heat recovery is an effective method of shortening specific energy consumption. new constructions of recuperators for heating and cupola furnaces have been designed and successfully introduced. two-stage recuperator with computer control providing blast heating up to 600 °C and reducing fuel consumption by 30% is of special interest.

  15. Diagnosis and Fault-tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Kinnaert, Michel; Lunze, Jan

    The book presents effective model-based analysis and design methods for fault diagnosis and fault-tolerant control. Architectural and structural models are used to analyse the propagation of the fault through the process, to test the fault detectability and to find the redundancies in the process...... the applicability of the presented methods. The theoretical results are illustrated by two running examples which are used throughout the book. The book addresses engineering students, engineers in industry and researchers who wish to get a survey over the variety of approaches to process diagnosis and fault...... that can be used to ensure fault tolerance. Design methods for diagnostic systems and fault-tolerant controllers are presented for processes that are described by analytical models, by discrete-event models or that can be dealt with as quantised systems. Four case studies on pilot processes show...

  16. Toleration out of respect?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    Under conditions of pluralism different cultures, interests or values can come into conflict, which raises the problem of how to secure peaceful co-existence. The idea of toleration historically emerged as an answer to this problem. Recently Rainer Forst has argued that toleration should not just...... at hand. The respect conception therefore seems to be at best a theoretical idea belonging in ideal-theory, not a useful practical solution to actual conflicts under conditions of pluralism....... that avoids various so-called ‘paradoxes of toleration’. The paper first examines whether Forst’s respect conception can be applied descriptively to distinguish between actual patterns of behaviour and classify different acts of toleration. Then the focus is shifted to toleration out of respect as a normative...

  17. Toleration out of respect?

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2013-01-01

    Under conditions of pluralism different cultures, interests or values can come into conflict, which raises the problem of how to secure peaceful co-existence. The idea of toleration historically emerged as an answer to this problem. Recently Rainer Forst has argued that toleration should not just...... at hand. The respect conception therefore seems to be at best a theoretical idea belonging in ideal-theory, not a useful practical solution to actual conflicts under conditions of pluralism....

  18. Fault-tolerant design

    CERN Document Server

    Dubrova, Elena

    2013-01-01

    This textbook serves as an introduction to fault-tolerance, intended for upper-division undergraduate students, graduate-level students and practicing engineers in need of an overview of the field.  Readers will develop skills in modeling and evaluating fault-tolerant architectures in terms of reliability, availability and safety.  They will gain a thorough understanding of fault tolerant computers, including both the theory of how to design and evaluate them and the practical knowledge of achieving fault-tolerance in electronic, communication and software systems.  Coverage includes fault-tolerance techniques through hardware, software, information and time redundancy.  The content is designed to be highly accessible, including numerous examples and exercises.  Solutions and powerpoint slides are available for instructors.   ·         Provides textbook coverage of the fundamental concepts of fault-tolerance; ·         Describes a variety of basic techniques for achieving fault-toleran...

  19. Variabilidade genética para características agronômicas em progênies de alface tolerantes ao calor Genetic variability for agronomic characteristics in lettuce progenies with heat tolerance

    Directory of Open Access Journals (Sweden)

    Maria da Conceição M de Souza

    2008-09-01

    Full Text Available Avaliaram-se progênies de alface tolerantes ao pendoamento precoce quanto aos caracteres agronômicos desejáveis à comercialização, bem como estimaram-se componentes genéticos importantes para o melhoramento da cultura. O delineamento experimental utilizado foi blocos ao acaso, com três repetições e 18 tratamentos (13 progênies F7, os genitores Verdinha, Regina e Tinto, e as cultivares Luisa e Babá de Verão. Estimaram-se as variâncias genéticas, fenotípica e ambiental, as herdabilidades e as correlações entre os caracteres número de folhas, peso fresco da planta e das folhas, diâmetro da planta, comprimento do caule e pendoamento. O teste F foi significativo (pLettuce progenies with tolerance to early bolting were evaluated in relation to commercially desirable agronomic characters, as well as to estimate important genetic components for crop breeding. The experimental design was random blocks with three replications and 18 treatments (13 progenies F7, the genitors Verdinha, Regina, and Tinto, and cultivars Luisa and Babá de Verão. The genetic, phenotypic, and environmental variances, the heritability, and the correlation among the characters number of leaves, plant and leaves fresh weight, plant diameter, stem length, and bolting, were estimated. The F test was significant (p<0,01 for all the studied characteristics. In the clustering of means by the Scott-Knott test, at 5% probability, treatments were assembled in two groups, except for plant diameter, in which cultivar Tinto remained isolated in a third group. The genetic variance was higher than the environmental variance for all evaluated characteristics, and the heritability, below 90%, revealed the environmental influence over some characters. When bolting was correlated to the other characteristics, results were positive and significant for most combinations, considering the genetic correlations. Under these experimental conditions, progeny 76 stood out for its low

  20. Police and Community-partnered Delivery System to Address ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The Community Policing Resource Centres (CPRCs), as they are called, have a support base that draws upon five departments - Health, Women and Child, ... IDRC is investing in local solutions to address climate change-related challenges in India, including heat stress, water management, and climate-related migration.

  1. A heat transfer textbook

    CERN Document Server

    Lienhard, John H

    2011-01-01

    This introduction to heat transfer offers advanced undergraduate and graduate engineering students a solid foundation in the subjects of conduction, convection, radiation, and phase-change, in addition to the related topic of mass transfer. A staple of engineering courses around the world for more than three decades, it has been revised and updated regularly by the authors, a pair of recognized experts in the field. The text addresses the implications, limitations, and meanings of many aspects of heat transfer, connecting the subject to its real-world applications and developing students' ins

  2. Convective heat transfer on Mars

    International Nuclear Information System (INIS)

    Arx, A.V. von; Delgado, A. Jr.

    1991-01-01

    An examination was made into the feasibility of using convective heat transfer on Mars to reject the waste heat from a Closed Brayton Cycle. Forced and natural convection were compared to thermal radiation. For the three radiator configurations studied, it was concluded that thermal radiation will yield the minimum mass and forced convection will result in the minimum area radiator. Other issues such as reliability of a fan motor were not addressed. Convective heat transfer on Mars warrants further investigation. However, the low density of the Martian atmosphere makes it difficult to utilize convective heat transfer without incurring a weight penalty

  3. Addressing adolescent pregnancy with legislation.

    Science.gov (United States)

    Montgomery, Tiffany M; Folken, Lori; Seitz, Melody A

    2014-01-01

    Adolescent pregnancy is a concern among many women's health practitioners. While it is practical and appropriate to work to prevent adolescent pregnancy by educating adolescents in health care clinics, schools and adolescent-friendly community-based organizations, suggesting and supporting legislative efforts to reduce adolescent pregnancy can help address the issue on an even larger scale. This article aims to help nurses better understand current legislation that addresses adolescent pregnancy, and to encourage support of future adolescent pregnancy prevention legislation. © 2014 AWHONN.

  4. Contribution to the heat integration of batch processes (with or without heat storage)

    OpenAIRE

    Krummenacher, Pierre; Favrat, Daniel

    2007-01-01

    This work addresses the indirect heat integration (i.e. resorting to intermediate heat storage) and the direct heat integration (i.e. heat exchanges between coexisting process streams) of batch processes. Tools and methods for the targeting of these two limiting cases of heat integration are proposed, and completed by the development and the application of an automatic design & optimization methodology using the Struggle genetic algorithm (GA). A brewery process is used to demonstrate the fea...

  5. Radial flow heat exchanger

    Science.gov (United States)

    Valenzuela, Javier

    2001-01-01

    A radial flow heat exchanger (20) having a plurality of first passages (24) for transporting a first fluid (25) and a plurality of second passages (26) for transporting a second fluid (27). The first and second passages are arranged in stacked, alternating relationship, are separated from one another by relatively thin plates (30) and (32), and surround a central axis (22). The thickness of the first and second passages are selected so that the first and second fluids, respectively, are transported with laminar flow through the passages. To enhance thermal energy transfer between first and second passages, the latter are arranged so each first passage is in thermal communication with an associated second passage along substantially its entire length, and vice versa with respect to the second passages. The heat exchangers may be stacked to achieve a modular heat exchange assembly (300). Certain heat exchangers in the assembly may be designed slightly differently than other heat exchangers to address changes in fluid properties during transport through the heat exchanger, so as to enhance overall thermal effectiveness of the assembly.

  6. Introduction to IP address management

    CERN Document Server

    Rooney, Tim

    2010-01-01

    "The book begins with a basic overview of IP networking, followed by chapters describing each of the three core IPAM technologies: IPv4 and IPv6 addressing, DHCP, and DNS. The next three chapters describe IPAM management techniques and practice, followed by chapters on IPv4-IPv6 co-existence, security and the IPAM business case"--

  7. Heat Stroke

    DEFF Research Database (Denmark)

    Mørch, Sofie Søndergaard; Andersen, Johnny Dohn Holmgren; Bestle, Morten Heiberg

    2017-01-01

    and mortality. This case report describes two Danish patients diagnosed with heat stroke syndrome during a heat wave in the summer of 2014. Both patients were morbidly obese and had several predisposing illnesses. However since heat stroke is a rare condition in areas with temperate climate, they were...... not diagnosed until several days after admittance; hence treatment with cooling was delayed. Both patients were admitted to the intensive care unit, where they were treated with an external cooling device and received treatment for complications. Both cases ended fatally. As global warming continues, more heat...

  8. Heat exchanger

    International Nuclear Information System (INIS)

    Watabe, Ichiro.

    1996-01-01

    An inner cylinder is disposed coaxially in a vertical vessel, and a plurality of heat transfer pipes are wound spirally on the outer circumference of the inner cylinder. High temperature sodium descends on the outer side of the inner cylinder while exchanging heat with water in the heat transfer pipes and becomes low temperature sodium. The low temperature sodium turns at the lower portion of the vessel, rises in a sodium exit pipe inserted to the inner cylinder and is discharged from the top of the vessel to the outside of the vessel. A portion of a cover gas (an inert gas such as argon) filled to the upper portion of the vessel intrudes into the space between the outer circumference of the sodium exit pipe and the inner circumference of the inner cylinder to form a heat insulation layer of the inert gas. This prevents heat exchange between the high temperature sodium before heat exchange and low temperature sodium after heat exchange. The heat exchanger is used as a secondary heat exchanger for coolants (sodium) of an FBR type reactor. (I.N.)

  9. Tolerance and recognition

    Directory of Open Access Journals (Sweden)

    Hans Marius Hansteen

    2014-12-01

    Full Text Available Even though “toleration” and “recognition” designate opposing attitudes (to tolerate something, implies a negative stance towards it, whereas recognition seems to imply a positive one, the concepts do not constitute mutually exclusive alternatives. However, “toleration” is often associated with liberal universalism, focusing on individual rights, whereas “recognition” often connotes communitarian perspectives, focusing on relations and identity. This paper argues that toleration may be founded on recognition, and that recognition may imply toleration. In outlining a differentiated understanding of the relationship between toleration and recognition, it seems apt to avoid an all-to-general dichotomy between universalism and particularism or, in other words, to reach beyond the debate between liberalism and communitarianism in political philosophy.The paper takes as its starting point the view that the discussion on toleration and diversity in intercultural communication is one of the contexts where it seems important to get beyond the liberal/communitarian dichotomy. Some basic features of Rainer Forst’s theory of toleration and Axel Honneth’s theory of the struggle for recognition are presented, in order to develop a more substantial understanding of the relationship between the concepts of toleration and recognition. One lesson from Forst is that toleration is a normatively dependent concept, i.e., that it is impossible to deduce principles for toleration and its limits from a theory of toleration as such. A central lesson from Honneth is that recognition – understood as a basic human need – is always conflictual and therefore dynamic.Accordingly, a main point in the paper is that the theory of struggles for and about recognition (where struggles for designates struggles within an established order of recognition, and struggles about designates struggles that challenge established orders of recognition may clarify what

  10. Escaping the tolerance trap

    International Nuclear Information System (INIS)

    Hammoudeh, S.; Madan, V.

    1994-01-01

    In order to examine the implications of the weakening of OPEC's responsiveness in adjusting its production levels, this paper explicitly incorporates rigidity in the quantity adjustment mechanism, thereby extending previous research which assumed smooth quantity adjustments. The rigidity is manifested in a tolerance range for the discrepancy between the declared target price and that of the market. This environment gives rise to a 'tolerance trap' which impedes the convergence process and inevitably brings the market to a standstill before its reaches the targeted price and revenue objectives. OPEC's reaction to the standstill has important implications for the achievement of the target-based equilibrium and for the potential collapse of the market price. This paper examines OPEC's policy options in the tolerance trap and reveals that the optional policy in order to break this impasse and move closer to the equilibrium point is gradually to reduce output and not to flood the market. (Author)

  11. Heat stress management in hot mines

    CSIR Research Space (South Africa)

    Schutte, P

    2009-09-01

    Full Text Available Metalliferous Mine in relation to Body-mass Index and Predicted VO 2 Max”, Occupational Medicine, Vol. 50(40), pp. 259- 263. 12. Kielblock, A.J. (2001), “Heat”, in Handbook of Occupational Health Practice in the South African Mining Industry, R. Guild, R... and the first form of heat acclimatization was introduced in 1925 (2). This rudimentary method of heat acclimatization was followed by a research program aimed both at obtaining a better understanding of human heat tolerance and at developing improved heat...

  12. Inequality, Tolerance, and Growth

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    2004-01-01

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequali...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  13. Inequality, Tolerance, and Growth

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    This paper argues for the importance of individuals' tolerance of inequality for economic growth. By using the political ideology of governments as a measure of revealed tolerance of inequality, the paper shows that controlling for ideology improves the accuracy with which the effects of inequali...... are measured. Results show that inequality reduces growth but more so in societies where people perceive it as being relatively unfair. Further results indicate that legal quality and social trust are likely transmission channels for the effects of inequality....

  14. Reliability and radiation tolerance of robots for nuclear applications

    Energy Technology Data Exchange (ETDEWEB)

    Lauridsen, K. [Risoe National Lab. (Denmark); Decreton, M. [SCK.CEN (Belgium); Seifert, C.C. [Siemens AG (Germany); Sharp, R. [AEA Technology (United Kingdom)

    1996-10-01

    The reliability of a robot for nuclear applications will be affected by environmental factors such as dust, water, vibrations, heat, and, in particular, ionising radiation. The present report describes the work carried out in a project addressing the reliability and radiation tolerance of such robots. A widely representative range of components and materials has been radiation tested and the test results have been collated in a database along with data provided by the participants from earlier work and data acquired from other sources. A radiation effects guide has been written for the use by designers of electronic equipment for robots. A generic reliability model has been set up together with generic failure strategies, forming the basis for specific reliability modelling carried out in other projects. Modelling tools have been examined and developed for the prediction of the performance of electronic circuits subjected to radiation. Reports have been produced dealing with the prediction and detection of upcoming failures in electronic systems. Operational experience from the use of robots in radiation work in various contexts has been compiled in a report, and another report has been written on cost/benefit considerations about the use of robots. Also the possible impact of robots on the safety of the surrounding plant has been considered and reported. (au) 16 ills., 236 refs.

  15. Thermal radiation heat transfer

    CERN Document Server

    Howell, John R; Mengüç, M Pinar

    2011-01-01

    Providing a comprehensive overview of the radiative behavior and properties of materials, the fifth edition of this classic textbook describes the physics of radiative heat transfer, development of relevant analysis methods, and associated mathematical and numerical techniques. Retaining the salient features and fundamental coverage that have made it popular, Thermal Radiation Heat Transfer, Fifth Edition has been carefully streamlined to omit superfluous material, yet enhanced to update information with extensive references. Includes four new chapters on Inverse Methods, Electromagnetic Theory, Scattering and Absorption by Particles, and Near-Field Radiative Transfer Keeping pace with significant developments, this book begins by addressing the radiative properties of blackbody and opaque materials, and how they are predicted using electromagnetic theory and obtained through measurements. It discusses radiative exchange in enclosures without any radiating medium between the surfaces-and where heat conduction...

  16. Genetic Approaches to Develop Salt Tolerant Germplasm

    KAUST Repository

    Tester, Mark A.

    2015-08-19

    Forty percent of the world\\'s food is produced under irrigation, and this is directly threatened by over-exploitation and changes in the global environment. One way to address this threat is to develop systems for increasing our ability to use lower quality water, in particular saline water. Low cost partial desalination of brackish water, use of saline water for cooling and increases in the salinity tolerance of crops can all contribute to the development of this new agricultural system. In this talk, the focus will be on the use of forward genetic approaches for discovery of genes related to salinity tolerance in barley and tomatoes. Rather than studying salinity tolerance as a trait in itself, we dissect salinity tolerance into a series of components that are hypothesised to contribute to overall salinity tolerance (following the paradigm of Munns & Tester, 2008). For example, one significant component of tolerance of most crop plants to moderate soil salinity is due to the ability to maintain low concentrations of Na+ in the leaves, and much analysis of this aspect has been done (e.g. Roy et al., 2013, 2014). A major site for the control of shoot Na+ accumulation is at the plasma membrane of the mature stele of the root. Alleles of HKT, a major gene underlying this transport process have been characterized and, in work led by Dr Rana Munns (CSIRO), have now been introgressed into commercial durum wheat and led to significantly increased yields in saline field conditions (Munns et al., 2012). The genotyping of mapping populations is now highly efficient. However, the ability to quantitatively phenotype these populations is now commonly limiting forward progress in plant science. The increasing power of digital imaging and computational technologies offers the opportunity to relieve this phenotyping bottleneck. The Plant Accelerator is a 4500m2 growth facility that provides non-destructive phenotyping of large populations of plants (http

  17. Heat exchanger

    International Nuclear Information System (INIS)

    Leigh, D.G.

    1976-01-01

    The arrangement described relates particularly to heat exchangers for use in fast reactor power plants, in which heat is extracted from the reactor core by primary liquid metal coolant and is then transferred to secondary liquid metal coolant by means of intermediate heat exchangers. One of the main requirements of such a system, if used in a pool type fast reactor, is that the pressure drop on the primary coolant side must be kept to a minimum consistent with the maintenance of a limited dynamic head in the pool vessel. The intermediate heat exchanger must also be compact enough to be accommodated in the reactor vessel, and the heat exchanger tubes must be available for inspection and the detection and plugging of leaks. If, however, the heat exchanger is located outside the reactor vessel, as in the case of a loop system reactor, a higher pressure drop on the primary coolant side is acceptable, and space restriction is less severe. An object of the arrangement described is to provide a method of heat exchange and a heat exchanger to meet these problems. A further object is to provide a method that ensures that excessive temperature variations are not imposed on welded tube joints by sudden changes in the primary coolant flow path. Full constructional details are given. (U.K.)

  18. Direct Heat

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1990-01-01

    Potential resources and applications of earth heat in the form of geothermal energy are large. United States direct uses amount to 2,100 MWt thermal and worldwide 8,850 MWt above a reference temperature of 35 degrees Celsius. Space and district heating are the major direct uses of geothermal energy. Equipment employed in direct use projects is of standard manufacture and includes downhole and circulation pumps, transmission and distribution pipelines, heat exchangers and convectors, heat pumps and chillers. Direct uses of earth heat discussed are space and district heating, greenhouse heating and fish farming, process and industrial applications. The economic feasibility of direct use projects is governed by site specific factors such as location of user and resource, resource quality, system load factor and load density, as well as financing. Examples are presented of district heating in Klamath Falls, and Elko. Further developments of direct uses of geothermal energy will depend on matching user needs to the resource, and improving load factors and load density.

  19. Toleration and its enemies

    DEFF Research Database (Denmark)

    Jarvad, Ib Martin

    2010-01-01

    After a presentation of the development of freedom of expression in Danish constitutional law, to freedom of the press in European human rights law - the Jersild case- to a right to mock and ridicule other faiths in recent Danish practice, the essay of Locke on toleration is examined, its...

  20. Toleration, Groups, and Multiculturalism

    DEFF Research Database (Denmark)

    Lægaard, Sune

    2014-01-01

    is routinely defined as involving an objection component, a power requirement and an acceptance component. The objection and acceptance components refer to reasons or dispositions of the subjects of toleration, e.g. public authorities deciding how to act in relation to groups. The power condition refers...

  1. 3HP tolerance

    DEFF Research Database (Denmark)

    2014-01-01

    Cells and cell cultures are provided that have improved tolerance to 3-hydroxypropionic acid (3HP). Genetic modifications to provide a mutated or overexpressed SFA1 gene or other enhancement of 3HP detoxification via a glutathione- dependent dehydrogenase reaction, including medium supplementation...

  2. Tolerance limits and tolerance intervals for ratios of normal random variables using a bootstrap calibration.

    Science.gov (United States)

    Flouri, Marilena; Zhai, Shuyan; Mathew, Thomas; Bebu, Ionut

    2017-05-01

    This paper addresses the problem of deriving one-sided tolerance limits and two-sided tolerance intervals for a ratio of two random variables that follow a bivariate normal distribution, or a lognormal/normal distribution. The methodology that is developed uses nonparametric tolerance limits based on a parametric bootstrap sample, coupled with a bootstrap calibration in order to improve accuracy. The methodology is also adopted for computing confidence limits for the median of the ratio random variable. Numerical results are reported to demonstrate the accuracy of the proposed approach. The methodology is illustrated using examples where ratio random variables are of interest: an example on the radioactivity count in reverse transcriptase assays and an example from the area of cost-effectiveness analysis in health economics. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Heat source versus heat sink

    International Nuclear Information System (INIS)

    Aussourd, P.

    1977-01-01

    This paper is a presentation of the method by which Electricite de France proposes to satisfy industrial, urban or agricultural heat needs if these prove economically justified. The arguments in the paper demonstrate the usefulness of studies on heat take-off from standardised nuclear units. General principles for extracting heat from nuclear power stations and the limit to the amount of steam that may be tapped off each unit are discussed. A diagram describes the heat production from a nuclear power station and shows the steam take-off where it emerges from the steam generators with or without back-pressure turbine. The connection principle for heat production from several nuclear units, separate nuclear-unit circuits and one common user circuit, is presented. (M.S.)

  4. Heat pipes

    CERN Document Server

    Dunn, Peter D

    1994-01-01

    It is approximately 10 years since the Third Edition of Heat Pipes was published and the text is now established as the standard work on the subject. This new edition has been extensively updated, with revisions to most chapters. The introduction of new working fluids and extended life test data have been taken into account in chapter 3. A number of new types of heat pipes have become popular, and others have proved less effective. This is reflected in the contents of chapter 5. Heat pipes are employed in a wide range of applications, including electronics cooling, diecasting and injection mo

  5. Addressing the workforce pipeline challenge

    Energy Technology Data Exchange (ETDEWEB)

    Leonard Bond; Kevin Kostelnik; Richard Holman

    2006-11-01

    A secure and affordable energy supply is essential for achieving U.S. national security, in continuing U.S. prosperity and in laying the foundations to enable future economic growth. To meet this goal the next generation energy workforce in the U.S., in particular those needed to support instrumentation, controls and advanced operations and maintenance, is a critical element. The workforce is aging and a new workforce pipeline, to support both current generation and new build has yet to be established. The paper reviews the challenges and some actions being taken to address this need.

  6. Biofilm induced tolerance towards antimicrobial peptides.

    Directory of Open Access Journals (Sweden)

    Anders Folkesson

    Full Text Available Increased tolerance to antimicrobial agents is thought to be an important feature of microbes growing in biofilms. We address the question of how biofilm organization affects antibiotic susceptibility. We established Escherichia coli biofilms with differential structural organization due to the presence of IncF plasmids expressing altered forms of the transfer pili in two different biofilm model systems. The mature biofilms were subsequently treated with two antibiotics with different molecular targets, the peptide antibiotic colistin and the fluoroquinolone ciprofloxacin. The dynamics of microbial killing were monitored by viable count determination, and confocal laser microscopy. Strains forming structurally organized biofilms show an increased bacterial survival when challenged with colistin, compared to strains forming unstructured biofilms. The increased survival is due to genetically regulated tolerant subpopulation formation and not caused by a general biofilm property. No significant difference in survival was detected when the strains were challenged with ciprofloxacin. Our data show that biofilm formation confers increased colistin tolerance to cells within the biofilm structure, but the protection is conditional being dependent on the structural organization of the biofilm, and the induction of specific tolerance mechanisms.

  7. Heat loss prediction of a confined premixed jet flame using a conjugate heat transfer approach

    NARCIS (Netherlands)

    Gövert, S.; Mira, D.; Zavala-Ake, M.; Kok, J.B.W.; Vázquez, M.; Houzeaux, G.

    2017-01-01

    The presented work addresses the investigation of the heat loss of a confined turbulent jet flame in a lab-scale combustor using a conjugate-heat transfer approach and large-eddy simulation. The analysis includes the assessment of the principal mechanisms of heat transfer in this combustion chamber:

  8. Heat Recovery Ventilation for Housing: Air-to-Air Heat Exchangers.

    Science.gov (United States)

    Corbett, Robert J.; Miller, Barbara

    The air-to-air heat exchanger (a fan powered ventilation device that recovers heat from stale outgoing air) is explained in this six-part publication. Topic areas addressed are: (1) the nature of air-to-air heat exchangers and how they work; (2) choosing and sizing the system; (3) installation, control, and maintenance of the system; (4) heat…

  9. What does fault tolerant Deep Learning need from MPI?

    Energy Technology Data Exchange (ETDEWEB)

    Amatya, Vinay C.; Vishnu, Abhinav; Siegel, Charles M.; Daily, Jeffrey A.

    2017-09-25

    Deep Learning (DL) algorithms have become the {\\em de facto} Machine Learning (ML) algorithm for large scale data analysis. DL algorithms are computationally expensive -- even distributed DL implementations which use MPI require days of training (model learning) time on commonly studied datasets. Long running DL applications become susceptible to faults -- requiring development of a fault tolerant system infrastructure, in addition to fault tolerant DL algorithms. This raises an important question: {\\em What is needed from MPI for designing fault tolerant DL implementations?} In this paper, we address this problem for permanent faults. We motivate the need for a fault tolerant MPI specification by an in-depth consideration of recent innovations in DL algorithms and their properties, which drive the need for specific fault tolerance features. We present an in-depth discussion on the suitability of different parallelism types (model, data and hybrid); a need (or lack thereof) for check-pointing of any critical data structures; and most importantly, consideration for several fault tolerance proposals (user-level fault mitigation (ULFM), Reinit) in MPI and their applicability to fault tolerant DL implementations. We leverage a distributed memory implementation of Caffe, currently available under the Machine Learning Toolkit for Extreme Scale (MaTEx). We implement our approaches by extending MaTEx-Caffe for using ULFM-based implementation. Our evaluation using the ImageNet dataset and AlexNet neural network topology demonstrates the effectiveness of the proposed fault tolerant DL implementation using OpenMPI based ULFM.

  10. Engineering microbes for tolerance to next-generation biofuels

    Directory of Open Access Journals (Sweden)

    Dunlop Mary J

    2011-09-01

    Full Text Available Abstract A major challenge when using microorganisms to produce bulk chemicals such as biofuels is that the production targets are often toxic to cells. Many biofuels are known to reduce cell viability through damage to the cell membrane and interference with essential physiological processes. Therefore, cells must trade off biofuel production and survival, reducing potential yields. Recently, there have been several efforts towards engineering strains for biofuel tolerance. Promising methods include engineering biofuel export systems, heat shock proteins, membrane modifications, more general stress responses, and approaches that integrate multiple tolerance strategies. In addition, in situ recovery methods and media supplements can help to ease the burden of end-product toxicity and may be used in combination with genetic approaches. Recent advances in systems and synthetic biology provide a framework for tolerance engineering. This review highlights recent targeted approaches towards improving microbial tolerance to next-generation biofuels with a particular emphasis on strategies that will improve production.

  11. Heat Waves

    Science.gov (United States)

    ... quickly. - Drink plenty of water regularly and often. - Eat small meals and eat more often. - Avoid using salt tablets ... plenty of water during a heat wave and eat smaller, more frequent meals. Text from "Are You Prepared?" by the Cass ( ...

  12. Deconditioning-induced exercise responses as influenced by heat acclimation

    Science.gov (United States)

    Shvartz, E.; Bhattacharya, A.; Sperinde, S. J.; Brock, P. J.; Sciaraffa, D.; Haines, R. F.; Greenleaf, J. E.

    1979-01-01

    A study to determine the effect of heat acclimation and physical training in temperate conditions on changes in exercise tolerance following water-immersion deconditioning is presented. Five young men were tested on a bicycle ergometer before and after heat acclimation and after water immersion. The subjects and the experimental procedure, heat acclimation and exercise training, water immersion, and exercise tolerance are discussed. Heat acclimation resulted in the usual decreases in exercise heart rate and rectal temperature and an increase in sweat rate. Water immersion resulted in substantial diuresis despite water consumed. The results show that heat acclimation provides an effective method of preventing the adverse effects of water-immersion deconditioning on exercise tolerance.

  13. HEAT EXCHANGER

    Science.gov (United States)

    Fox, T.H. III; Richey, T. Jr.; Winders, G.R.

    1962-10-23

    A heat exchanger is designed for use in the transfer of heat between a radioactive fiuid and a non-radioactive fiuid. The exchanger employs a removable section containing the non-hazardous fluid extending into the section designed to contain the radioactive fluid. The removable section is provided with a construction to cancel out thermal stresses. The stationary section is pressurized to prevent leakage of the radioactive fiuid and to maintain a safe, desirable level for this fiuid. (AEC)

  14. Energy Address Delivery Technologies and Thermal Transformations in Food Production

    Directory of Open Access Journals (Sweden)

    Burdo O.G.

    2016-08-01

    Full Text Available In this article, energetic and technical paradoxes in food nanotechnologies and traditional approaches to evaluation of energy recourses using are considered. Hypotheses of improvement of food production energy technologies are formulated. Classification of principles of address delivery of energy to food raw materials elements is given. We had substantiated the perspective objectives for heat-pumps installations and biphasic heat-transfer systems. The energy efficiency of new technolo-gies is compared on base of the number of energy impact. Principles of mass transfer modeling in ex-traction, dehydration and pasteurization combined processes are considered by food production exam-ple. The objectives of mathematical modeling of combined hydrodynamic and heat and mass transfer processes in modern energy technologies are set. The fuel energy conversion diagrams for drying, in-novative installations on the base of thermal siphons, heat pumps and electromagnetic energy genera-tors are represented. In this article, we illustrate how electromagnetic field, biphasic heat-transfer sys-tems and heat pumps can be effective tools for energy efficiency technologies.

  15. Oral tolerance induction with altered forms of ovalbumin

    Directory of Open Access Journals (Sweden)

    Stransky B.

    1998-01-01

    Full Text Available As a T cell-dependent phenomenon, oral tolerance is not expected to depend necessarily on native configuration of antigens. We investigated the induction of oral tolerance with modified ovalbumin (Ova. Oral administration of heat-denatured (HD-Ova and cyanogen bromide-degraded ovalbumin was less effective than native Ova in inducing oral tolerance in B6D2F1 mice. HD-Ova was effective in suppressing delayed-type hypersensitivity (DTH reactions but did not suppress specific antibody formation. Injection of Ova directly into the stomach, but not into the ileum or cecum, suppressed subsequent immunization to DTH reactions. Gavage with protease inhibitors (aprotinin or ovomucoid before gavage with Ova was ineffective in blocking tolerance induction. Treatment with hydroxyurea to destroy cycling cells 24 h before gavage with Ova blocked oral tolerance induction and also the possibility to passively transfer tolerance to naive recipients with the serum of mice gavaged with Ova 1 h before. The implications of these findings about oral tolerance induction are discussed

  16. Abuse Tolerance Improvements

    Energy Technology Data Exchange (ETDEWEB)

    Orendorff, Christopher J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Nagasubramanian, Ganesan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fenton, Kyle R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Allcorn, Eric [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-10-01

    As lithium-ion battery technologies mature, the size and energy of these systems continues to increase (> 50 kWh for EVs); making safety and reliability of these high energy systems increasingly important. While most material advances for lithium-ion chemistries are directed toward improving cell performance (capacity, energy, cycle life, etc.), there are a variety of materials advancements that can be made to improve lithium-ion battery safety. Issues including energetic thermal runaway, electrolyte decomposition and flammability, anode SEI stability, and cell-level abuse tolerance continue to be critical safety concerns. This report highlights work with our collaborators to develop advanced materials to improve lithium-ion battery safety and abuse tolerance and to perform cell-level characterization of new materials.

  17. Fault Tolerant Control Systems

    DEFF Research Database (Denmark)

    Bøgh, S. A.

    This thesis considered the development of fault tolerant control systems. The focus was on the category of automated processes that do not necessarily comprise a high number of identical sensors and actuators to maintain safe operation, but still have a potential for improving immunity to component...... failures. It is often feasible to increase availability for these control loops by designing the control system to perform on-line detection and reconfiguration in case of faults before the safety system makes a close-down of the process. A general development methodology is given in the thesis...... that carried the control system designer through the steps necessary to consider fault handling in an early design phase. It was shown how an existing control loop with interface to the plant wide control system could be extended with three additional modules to obtain fault tolerance: Fault detection...

  18. Moral hypocrisy: addressing some alternatives.

    Science.gov (United States)

    Batson, C Daniel; Thompson, Elizabeth R; Chen, Hubert

    2002-08-01

    Two studies addressed alternative explanations for 3 pieces of evidence supporting the existence of moral hypocrisy. In Study 1, no support was found for the idea that low salience of social standards accounts for falsifying the result of a coin flip to assign oneself a more desirable task. In Study 2, no support was found for the idea that responses of those who honestly win the flip account for the higher ratings of morality of their action by participants who assign themselves the more desirable task after flipping the coin. Also, no support was found for the idea that responses of those who honestly win the flip account for the inability of personal moral responsibility measures to predict moral action. Instead, results of both studies provided additional evidence of moral hypocrisy.

  19. Helminths and immunological tolerance

    OpenAIRE

    Johnston, Chris J C; McSorley, Henry J; Anderton, Stephen M; Wigmore, Stephen J; Maizels, Rick M

    2014-01-01

    Current immunosuppression regimens for solid-organ transplantation have shown disappointing efficacy in the prevention of chronic allograft rejection and carry unacceptable risks including toxicity, neoplasia, and life-threatening infection. Achievement of immunological tolerance (long-term antigen unresponsiveness in an immunocompetent host) presents the exciting prospect of freedom from immunosuppression for transplant recipients. It is now 60 years since the first demonstration of immunolo...

  20. Toleration, Liberty and Privileges

    DEFF Research Database (Denmark)

    Simonton, Deborah

    2017-01-01

    Guilds are usually seen as the epitome of economic regulation and organization in early modern European towns. As organisations closely tied to the nominal male lifecycle, historians of women have tended to be chary of them and identified guilds as a key mechanism for restricting women’s access t...... to trade could depend on gaining tolerations, earning the liberty of the trade and using the liberties associated with it....

  1. Socially-Tolerable Discrimination

    OpenAIRE

    Amegashie, J. Atsu

    2008-01-01

    History is replete with overt discrimination on the basis of race, gender, age, citizenship, ethnicity, marital status, academic performance, health status, volume of market transactions, religion, sexual orientation, etc. However, these forms of discrimination are not equally tolerable. For example, discrimination based on immutable or prohibitively unalterable characteristics such as race, gender, or ethnicity is much less acceptable. Why? I develop a simple rent-seeking model of conflict w...

  2. Thermal pain tolerance and pain rating in normal subjects: Gender and age effects.

    Science.gov (United States)

    Lue, Y-J; Wang, H-H; Cheng, K-I; Chen, C-H; Lu, Y-M

    2018-02-01

    Thermal detection thresholds and thermal pain thresholds are important in quantitative sensory testing. Although they have been well studied for assessing somatosensory function, the investigation of thermal pain tolerance has been insufficient. The aim of this study was to explore the characteristics of thermal pain tolerance and pain ratings in healthy subjects. Cold pain tolerance (CPTol) and heat pain tolerance (HPTol) were tested in 213 healthy adults aged 18-81 years recruited from the local community. The thermal detection and thermal pain thresholds were also tested to investigate the association with pain tolerance. The visual analogue scale (VAS) was used for assessing pain severity immediately after the thermal pain and tolerance tests. The normality of the CPTol and HPTol was acceptable. Most participants rated the pain induced by the CPTol and HPTol testing as moderate. HPTol was lower in women than in men (p = 0.001), but CPTol did not differ between sexes. The pain ratings of CPTol and HPTol did not differ between sexes, but significant age effects were observed. The association of the tolerance temperature with pain ratings was weak, while those of pain ratings for CPTol and HPTol were strong (r = 0.87). Women were more sensitive to tolerance heat pain stimuli. Younger participants reported more pain for thermal pain and tolerance tests. Thermal pain tolerance and pain rating for the thermal pain tolerance temperature depend on gender and age. Women are more sensitive to heat temperatures, young people rate more pain, and the pain ratings of heat and cold are strongly correlated. © 2018 European Pain Federation - EFIC®.

  3. Residential Variable-Capacity Heat Pumps Sized to Heating Loads

    Energy Technology Data Exchange (ETDEWEB)

    Munk, Jeffrey D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jackson, Roderick K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Odukomaiya, Adewale [Georgia Inst. of Technology, Atlanta, GA (United States); Gehl, Anthony C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2014-01-01

    Variable capacity heat pumps are an emerging technology offering significant energy savings potential and improved efficiency. With conventional single-speed systems, it is important to appropriately size heat pumps for the cooling load as over-sizing would result in cycling and insufficient latent capacity required for humidity control. These appropriately sized systems are often under-sized for the heating load and require inefficient supplemental electric resistance heat to meet the heating demand. Variable capacity heat pumps address these shortcomings by providing an opportunity to intentionally size systems for the dominant heating season load without adverse effects of cycling or insufficient dehumidification in the cooling season. This intentionally-sized system could result in significant energy savings in the heating season, as the need for inefficient supplemental electric resistance heat is drastically reduced. This is a continuation of a study evaluating the energy consumption of variable capacity heat pumps installed in two unoccupied research homes in Farragut, a suburb of Knoxville, Tennessee. In this particular study, space conditioning systems are intentionally sized for the heating season loads to provide an opportunity to understand and evaluate the impact this would have on electric resistance heat use and dehumidification. The results and conclusions drawn through this research are valid and specific for portions of the Southeastern and Midwestern United States falling in the mixed-humid climate zone. While other regions in the U.S. do not experience this type of climate, this work provides a basis for, and can help understand the implications of other climate zones on residential space conditioning energy consumption. The data presented here will provide a framework for fine tuning residential building EnergyPlus models that are being developed.

  4. Residential CO{sub 2} heat pump system for combined space heating and hot water heating

    Energy Technology Data Exchange (ETDEWEB)

    Stene, Joern

    2004-02-01

    may result in a considerable increase in the inlet water temperature for the DHW preheating gas cooler. This will in turn reduce the COP of the integrated CO{sub 2} heat pump. The thermodynamic losses are highest at large initial temperature differences for the DHW and the city water, small charging volumes and low gas cooler heating capacities. Inevitable mixing of hot and cold water in the tank will lead to further increase in the thermodynamic losses for the CO{sub 2} heat pump system. (10) One possible way to reduce internal conductive heat transfer and avoid the mixing in cylindrical single-shell DHW storage tanks, is to separate the DHW and the city water by means of a movable plate with low thermal conductivity. The concept proved to give satisfactory thermal performance and functionality at atmospheric operating conditions. However, definite conclusions regarding the functionality, thermal performance and optimum design can only be drawn after full-scale testing has been carried out in a pressurised tank. First-costs as well as the long-term reliability of the insulating plate are also important issues that need to be further addressed.

  5. Lead chalcogenides based IR photosensitive array detectors with coordinate addressing

    Science.gov (United States)

    Agranov, G. A.; Novoselov, S. K.; Stepanov, R. M.; Doon, A. Z.; Pashkevich, A. V.; Ivanov, A. I.; Nemchuk, I. K.; Nesterov, V. K.; Skoriukin, V. E.

    1992-12-01

    Coordinate addressed photodetector arrays based on thin films of lead chalcogenides and operating in different wavebands of the infrared spectral regions are described. The arrays feature high sensitivity, close to BLIP mode, wide dynamic range, and low heat dissipation. Their advantages include random access, element block selection, image scaling, and on chip data encoding. Different design configurations with elements from 128 by 128 to 512 by 512 are discussed and experimental parameters and characteristics of the experimental arrays are presented.

  6. Survival tactics within thermally-challenging roosts: heat tolerance ...

    African Journals Online (AJOL)

    Microclimates were thermally challenging, being very hot (>40°C) for several hours daily in summer and autumn, and cold (<10°C) for much of the night in winter Thermal preference tests revealed that the bats actively selected temperature zones (35°- 42°C) in which basal metabolic rate could be maintained, and above the ...

  7. Survival tactics within thermally-challenging roosts: heat tolerance ...

    African Journals Online (AJOL)

    Microclimates were thermally challenging, being very hot (>40°C) for several hours daily in summer and autumn, and cold «10°C) for much of the night in winter. Thermal preference tests revealed that the bats actively selected temperature zones (35°-. 42°C) in which basal metabolic rate could be maintained, and above the ...

  8. genetic evaluation of seedling heat tolerance in sorghum abstract ...

    African Journals Online (AJOL)

    Administrator

    hybrids were produced using tester cytoplasmic male sterility A-lines but F1 s for deriving progeny were made by plastic bag emasculation on the male fertile line, as were the BC1 and BC11 x F1 s. Because this method does not ensure complete crossing, hybrid plants were identified in each F1 row. Laboratory techniques.

  9. THERMOLABILlTY, HEAT TOLERANCE AND RENAL FUNCTION IN ...

    African Journals Online (AJOL)

    dassie, the following observations were made: The dassie is unable to exist indefinitely on a dry diet without ... haviour and general ecology of Procavia (Sale 1965, 1966a, 1966b, 1970), the water economy of these animals has .... field conditions. Blood and urine samples were collected immediately after killing the animals.

  10. Survival tactics within thermally-challenging roosts: heat tolerance ...

    African Journals Online (AJOL)

    ured ambient dry bulb temperature, relative humidity, solar radiation levels and windspeed. Data were ... their location(s) in the roost was determined in- directly using a stethoscope placed against the wooden panel- ling. .... ing the peak of the day (10:00-14:00), external solar radiation levels were highly variable owing to ...

  11. A NOTE ON HEAT TOLERANCE AND THYROID FUNCTION IN ...

    African Journals Online (AJOL)

    Johnson, 1957). Yousef, Hahn & Johnson (1968) stated that the inverse relationship betrveen thyroid activity and suitability of environment provides a means of adaptation to environments above or below thermoneutral tempera- ture. ... lute-Ames Company). At 12h00 rectal and skin temperatures were recorded using ...

  12. Selection of arabica coffee progenies tolerant to heat stress

    Directory of Open Access Journals (Sweden)

    Alexsandro Lara Teixeira

    2015-07-01

    Full Text Available Due to high temperatures, practically all coffee farms in the state of Rondonia are of the C. canephora species. Thus, importing arabica coffee from other states becomes necessary for composition of blends, as well as for the specialty or gourmet coffee market. The purpose of this study was to select arabica coffee genotypes that exhibit satisfactory agronomic performance under high temperature conditions. The experiment was conducted in OuroPreto do Oeste, RO, Brazil, with mean annual temperature of 25.8°C and mean annual rainfall of 2300mm year-1. The experiment was composed of 114 arabica coffee genotypes, with 103 progenies and eleven control cultivars, provided by EPAMIG. A randomized block experimental design was used with three replications, spacing of 3.0x1.0 meters and five plants per plot. All the crop seasons showed significant difference for the green coffee yield trait. In joint analysis, significant differences were detected among progenies and control cultivars. In the average of the four harvests, green coffee yield was 32.38 bags ha-1. The cultivars 'CatuaíVermelho IAC 15', 'Obatã IAC 1669-20' and 'Catucaí Amarelo 2SLCAK' stood out, achieving yields greater than 40 bags ha-1. The gain obtained from selection was 14.33 bags ha-1, which is equivalent to an increase of 44.04% in production of green coffee. The progeny H514-7-10-6-2-3-9 stood out with an average yield of 51.20 bags ha-1. In regard to maturation cycle, 56% of the progenies were classified as early maturity and 44% as medium maturity. Late maturity genotypes were not observed

  13. Effect of summer climatic conditions on different heat tolerance ...

    African Journals Online (AJOL)

    Die invloed van klimaattoestande gedurende die somer op verskillende warmteverdraagsaamheidsaanwysers is by Fries- en Jerseykoeie wat in oop kampe sonder enige beskutting teen sonstraling aangehou is, bepaal. 'n Volledige dieet (15.0% RP en 10.8 MJ ME/kg) is daagliks op 'n ad libitum-basis aan koeie in ...

  14. Influence of Ear Surface Area on Heat Tolerance of Composite ...

    African Journals Online (AJOL)

    Low correlation (r = 0.12) was observed between body weight and ear width. There were no correlations between ear width, respiratory rates and pulse rate. However, a residual correlation (r = -0.03) was obtained between ear width and body temperature. Large ear surface area in composite rabbits enhances better ...

  15. Unwanted heat

    International Nuclear Information System (INIS)

    Benka, M.

    2006-01-01

    The number of small heating plants using biomass is growing. According to TREND's information, Hrinovska energeticka, is the only one that controls the whole supplier chain in cooperation with its parent company in Bratislava. Starting with the collection and processing of wood chips by burning, heat production and heat distribution to the end user. This gives the company better control over costs and consequently its own prices. Last year, the engineering company, Hrinovske storjarne, decided to focus only on its core business and sold its heating plant, Hrinovske tepelne hospodarstvo, to Intech Slovakia and changed the company name to Hrinovska energeticka. Local companies and inhabitants were concerned that the new owner would increase prices. But the company publicly declared and kept promises that the heat price for households would remain at 500 Slovak crowns/gigajoule (13.33 EUR/gigajoule ), one of the lowest prices in Slovakia. This year the prices increased slightly to 570 Slovak crowns (15.2 EUR). 'We needed - even at the cost of lower profit - to satisfy our customers so that we would not lose them. We used this time for transition to biomass. This will allow us to freeze our prices in the coming years,' explained the statutory representative of the company, Ivan Dudak. (authors)

  16. A region addresses patient safety.

    Science.gov (United States)

    Feinstein, Karen Wolk; Grunden, Naida; Harrison, Edward I

    2002-06-01

    The Pittsburgh Regional Healthcare Initiative (PRHI) is a coalition of 35 hospitals, 4 major insurers, more than 30 major and small-business health care purchasers, dozens of corporate and civic leaders, organized labor, and partnerships with state and federal government all working together to deliver perfect patient care throughout Southwestern Pennsylvania. PRHI believes that in pursuing perfection, many of the challenges facing today's health care delivery system (eg, waste and error in the delivery of care, rising costs, frustration and shortage among clinicians and workers, financial distress, overcapacity, and lack of access to care) will be addressed. PRHI has identified patient safety (nosocomial infections and medication errors) and 5 clinical areas (obstetrics, orthopedic surgery, cardiac surgery, depression, and diabetes) as ideal starting points. In each of these areas of work, PRHI partners have assembled multifacility/multidisciplinary groups charged with defining perfection, establishing region-wide reporting systems, and devising and implementing recommended improvement strategies and interventions. Many design and conceptual elements of the PRHI strategy are adapted from the Toyota Production System and its Pittsburgh derivative, the Alcoa Business System. PRHI is in the proof-of-concept phase of development.

  17. Addressing Semantic Geographic Information Systems

    Directory of Open Access Journals (Sweden)

    Salvatore F. Pileggi

    2013-11-01

    Full Text Available The progressive consolidation of information technologies on a large scale has been facilitating and progressively increasing the production, collection, and diffusion of geographic data, as well as facilitating the integration of a large amount of external information into geographic information systems (GIS. Traditional GIS is transforming into a consolidated information infrastructure. This consolidated infrastructure is affecting more and more aspects of internet computing and services. Most popular systems (such as social networks, GPS, and decision support systems involve complex GIS and significant amounts of information. As a web service, GIS is affected by exactly the same problems that affect the web as a whole. Therefore, next generation GIS solutions have to address further methodological and data engineering challenges in order to accommodate new applications’ extended requirements (in terms of scale, interoperability, and complexity. The conceptual and semantic modeling of GIS, as well as the integration of semantics into current GIS, provide highly expressive environments that are capable of meeting the needs and requirements of a wide range of applications.

  18. Physiological and molecular mechanisms associated with cross tolerance between hypoxia and low temperature in Thaumatotibia leucotreta

    DEFF Research Database (Denmark)

    Boardman, Leigh; Sørensen, Jesper Givskov; Terblanche, John S

    2015-01-01

    correlated with increased membrane fluidity (increased UFA:SFA) and/or alterations in heat shock protein 70 (HSP70); while general mechanical stress (shaking) and heat (2 h at 35 C) do not elicit cross tolerance (no change in survival or molecular responses). We therefore found support for some limited cold...

  19. Heat convection

    Energy Technology Data Exchange (ETDEWEB)

    Jiji, L.M. [City Univ. of New York, NY (United States). Dept. of Mechanical Engineering

    2006-07-01

    Professor Jiji's broad teaching experience lead him to select the topics for this book to provide a firm foundation for convection heat transfer with emphasis on fundamentals, physical phenomena, and mathematical modelling of a wide range of engineering applications. Reflecting recent developments, this textbook is the first to include an introduction to the challenging topic of microchannels. The strong pedagogic potential of Heat Convection is enhanced by the following ancillary materials: (1) Power Point lectures, (2) Problem Solutions, (3) Homework Facilitator, and, (4) Summary of Sections and Chapters. (orig.)

  20. Heat Convection

    Science.gov (United States)

    Jiji, Latif M.

    Professor Jiji's broad teaching experience lead him to select the topics for this book to provide a firm foundation for convection heat transfer with emphasis on fundamentals, physical phenomena, and mathematical modelling of a wide range of engineering applications. Reflecting recent developments, this textbook is the first to include an introduction to the challenging topic of microchannels. The strong pedagogic potential of Heat Convection is enhanced by the follow ing ancillary materials: (1) Power Point lectures, (2) Problem Solutions, (3) Homework Facilitator, and, (4) Summary of Sections and Chapters.

  1. Control challenges in domestic heating systems

    DEFF Research Database (Denmark)

    Thybo, Honglian; Larsen, Lars F. S.; Weitzmann, Peter

    2007-01-01

    The objective of this paper is to analyze domestic heating applications and identify unfavorable building constructions and control challenges to be addressed by high performance heating control systems. Heating of domestic houses use a large amount of the total energy consumption in Scandinavia....... Hence the potential of reducing energy consumption by applying high performance control is vast. Indoor climate issues are becoming more in focus, which also leads to a demand for high performance heating systems. The paper presents an analysis of how the building elements of today's domestic houses...... with water based floor heating affect the control challenge. The analysis is documented with simulation results....

  2. Molecular investigations on grain filling rate under terminal heat ...

    African Journals Online (AJOL)

    Ezedom Theresa

    2013-07-10

    Jul 10, 2013 ... Grain yield under post anthesis high temperature stress is largely influenced by grain filling rate (GFR). To investigate molecular basis of this trait, a set of 111 recombinant inbred lines (RILs) derived from Raj. 4014, a heat sensitive genotype and WH 730, heat tolerant cultivar was phenotyped during 2009- ...

  3. Geographical influence of heat stress on milk production of Holstein ...

    African Journals Online (AJOL)

    Geographical influence of heat stress on milk production of Holstein dairy cattle on pasture in South Africa under current and future climatic conditions. ... Possible long-term viable alternatives are suggested, including changes in nutrition and replacing existing breeds with more heat tolerant genotypes. Keywords: climate ...

  4. Molecular investigations on grain filling rate under terminal heat ...

    African Journals Online (AJOL)

    Grain yield under post anthesis high temperature stress is largely influenced by grain filling rate (GFR). To investigate molecular basis of this trait, a set of 111 recombinant inbred lines (RILs) derived from Raj 4014, a heat sensitive genotype and WH 730, heat tolerant cultivar was phenotyped during 2009-2010 and ...

  5. Induction of thermotolerance through heat acclimation in lablab ...

    African Journals Online (AJOL)

    The acclimation of plants to moderately high temperature plays an important role in inducing plant tolerance to subsequent lethal temperatures. This study was performed to investigate the effects of heat acclimation and sudden heat stress on the antioxidant and metabolic profile of lablab bean (Dolichos lablab). Following ...

  6. Allergen Immunotherapy and Tolerance

    Directory of Open Access Journals (Sweden)

    Tomokazu Matsuoka

    2013-01-01

    Full Text Available Successful allergen-specific immunotherapy (AIT is associated with a marked decrease in symptoms on allergen exposure, a reduced requirement for 'rescue' anti-allergic drugs and improvement in patients' quality of life. These benefits persist for at least several years following discontinuation of immunotherapy - the hallmark of clinical and immunological tolerance. AIT has been shown to modulate both innate and adaptive immunological responses. Early suppression of innate effector cells of allergic inflammation (mast cells, basophils, regulation of pro-allergic T helper 2 type (Th 2 responses and IgE+ B cell responses have been shown to occur both in the tissue and in the peripheral blood during AIT. The allergen-tolerant state is associated with local and systemic induction of distinct populations of allergen-specific T regulatory cells including IL-10+ Tregs (Tr1 cells, TGF-P+ Tregs and FoxP3+ memory T regs. B cells are switched in favour of producing IgG (particularly IgG4 antibodies and associated blocking activity for IgE-dependent events, including basophil activation and IgE-facilitated allergen binding to B cells. An induction of IL-10+ B regulatory cells and alterations in dendritic cell subsets have also recently been described. These events are followed by the induction of T regulatory cells, suppression of allergen-specific T cell proliferation and immune deviation from Th2 in favour of Th1 responses. Alternative mechanisms of tolerance include apoptosis/deletion of antigen-specific memory Th2 cells and/or a failure of co-stimulation leading to T cell anergy.

  7. Performance of a Heating Block System Designed for Studying the Heat Resistance of Bacteria in Foods

    Science.gov (United States)

    Kou, Xiao-xi; Li, Rui; Hou, Li-xia; Huang, Zhi; Ling, Bo; Wang, Shao-jin

    2016-01-01

    Knowledge of bacteria’s heat resistance is essential for developing effective thermal treatments. Choosing an appropriate test method is important to accurately determine bacteria’s heat resistances. Although being a major factor to influence the thermo-tolerance of bacteria, the heating rate in samples cannot be controlled in water or oil bath methods due to main dependence on sample’s thermal properties. A heating block system (HBS) was designed to regulate the heating rates in liquid, semi-solid and solid foods using a temperature controller. Distilled water, apple juice, mashed potato, almond powder and beef were selected to evaluate the HBS’s performance by experiment and computer simulation. The results showed that the heating rates of 1, 5 and 10 °C/min with final set-point temperatures and holding times could be easily and precisely achieved in five selected food materials. A good agreement in sample central temperature profiles was obtained under various heating rates between experiment and simulation. The experimental and simulated results showed that the HBS could provide a sufficiently uniform heating environment in food samples. The effect of heating rate on bacterial thermal resistance was evaluated with the HBS. The system may hold potential applications for rapid and accurate assessments of bacteria’s thermo-tolerances. PMID:27465120

  8. Performance of a Heating Block System Designed for Studying the Heat Resistance of Bacteria in Foods

    Science.gov (United States)

    Kou, Xiao-Xi; Li, Rui; Hou, Li-Xia; Huang, Zhi; Ling, Bo; Wang, Shao-Jin

    2016-07-01

    Knowledge of bacteria’s heat resistance is essential for developing effective thermal treatments. Choosing an appropriate test method is important to accurately determine bacteria’s heat resistances. Although being a major factor to influence the thermo-tolerance of bacteria, the heating rate in samples cannot be controlled in water or oil bath methods due to main dependence on sample’s thermal properties. A heating block system (HBS) was designed to regulate the heating rates in liquid, semi-solid and solid foods using a temperature controller. Distilled water, apple juice, mashed potato, almond powder and beef were selected to evaluate the HBS’s performance by experiment and computer simulation. The results showed that the heating rates of 1, 5 and 10 °C/min with final set-point temperatures and holding times could be easily and precisely achieved in five selected food materials. A good agreement in sample central temperature profiles was obtained under various heating rates between experiment and simulation. The experimental and simulated results showed that the HBS could provide a sufficiently uniform heating environment in food samples. The effect of heating rate on bacterial thermal resistance was evaluated with the HBS. The system may hold potential applications for rapid and accurate assessments of bacteria’s thermo-tolerances.

  9. Renewable Heating And Cooling

    Science.gov (United States)

    Renewable heating and cooling is a set of alternative resources and technologies that can be used in place of conventional heating and cooling technologies for common applications such as water heating, space heating, space cooling and process heat.

  10. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... for signs of heat stroke or exhaustion. Heat Stroke and Exhaustion Symptoms of early heat exhaustion symptoms ... heavy sweating; nausea; and giddiness. Symptoms of heat stroke (late stage of heat illness) include flushed, hot, ...

  11. State, religion and toleration

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    2009-01-01

    Contribution to Religion and State - From separation to cooperation? Legal-philosophical reflections for a de-secularized world. (IVR Cracow Special Workshop). Eds. Bart. C. Labuschagne & Ari M. Solon. Abstract: Toleration is indeed a complex phenomenon. A discussion of the concept will have...... to underline not only the broadmindedness and liberty of individuals or of groups, but also the relevant distinctions and arguments in political philosophy, epistemology, philosophy of religion and philosophical anthropology and their connection with educational issues. Through a discussion of these relations...

  12. Fault Tolerant Computer Architecture

    CERN Document Server

    Sorin, Daniel

    2009-01-01

    For many years, most computer architects have pursued one primary goal: performance. Architects have translated the ever-increasing abundance of ever-faster transistors provided by Moore's law into remarkable increases in performance. Recently, however, the bounty provided by Moore's law has been accompanied by several challenges that have arisen as devices have become smaller, including a decrease in dependability due to physical faults. In this book, we focus on the dependability challenge and the fault tolerance solutions that architects are developing to overcome it. The two main purposes

  13. Performance-Oriented Fault Tolerance in Computing Systems

    NARCIS (Netherlands)

    Borodin, D.

    2010-01-01

    In this dissertation we address the overhead reduction of fault tolerance (FT) techniques. Due to technology trends such as decreasing feature sizes and lowering voltage levels, FT is becoming increasingly important in modern computing systems. FT techniques are based on some form of redundancy. It

  14. Hyperspectral imaging to identify salt-tolerant wheat lines

    Science.gov (United States)

    In order to address the worldwide growing demand for food, agriculture is facing certain challenges and limitations. One of the important threats limiting crop productivity is salinity. Identifying salt tolerate varieties is crucial to mitigate the negative effects of this abiotic stress in agricult...

  15. In the Eyes of the Beholder: Urban Student Perceptions of Zero Tolerance Policy

    Science.gov (United States)

    McNeal, Laura; Dunbar, Christopher, Jr.

    2010-01-01

    Zero tolerance policy was created as a result of the Gun Free Schools Act of 1994. Varied views exist on zero tolerance policy that include its substantive impact, for whom it is intended, and its viability to address the problem of school violence. Parents, politicians, principals, and teachers have stated their views on the issues. However,…

  16. Heat exchangers

    International Nuclear Information System (INIS)

    1975-01-01

    The tubes of a heat exchanger tube bank have a portion thereof formed in the shape of a helix, of effective radius equal to the tube radius and the space between two adjacent tubes, to tangentially contact the straight sections of the tubes immediately adjacent thereto and thereby provide support, maintain the spacing and account for differential thermal expansion thereof

  17. Heat Rash

    Science.gov (United States)

    ... too much. The sweat gets trapped under your skin and blocks your sweat glands. If your pores cannot clear out the sweat, you may get ... irritation caused by clothing that rubs against the skin. If your rash is severe, ... can block pores even more. Living with heat rash Whether you ...

  18. Heat exchanger

    International Nuclear Information System (INIS)

    Wolowodiuk, W.

    1976-01-01

    A heat exchanger of the straight tube type is described in which different rates of thermal expansion between the straight tubes and the supply pipes furnishing fluid to those tubes do not result in tube failures. The supply pipes each contain a section which is of helical configuration

  19. Realization and Addressing Analysis In Blockchain Bitcoin

    Science.gov (United States)

    Sakti Arief Daulay, Raja; Michrandi Nasution, Surya; Paryasto, Marisa W.

    2017-11-01

    The implementation research and analyze address blockchain on this bitcoin will have the results that refers to making address bitcoin a safe and boost security of address the bitcoin. The working mechanism of blockchain in making address bitcoin which is already in the blockchain system.

  20. Helminths and immunological tolerance.

    Science.gov (United States)

    Johnston, Chris J C; McSorley, Henry J; Anderton, Stephen M; Wigmore, Stephen J; Maizels, Rick M

    2014-01-27

    Current immunosuppression regimens for solid-organ transplantation have shown disappointing efficacy in the prevention of chronic allograft rejection and carry unacceptable risks including toxicity, neoplasia, and life-threatening infection. Achievement of immunological tolerance (long-term antigen unresponsiveness in an immunocompetent host) presents the exciting prospect of freedom from immunosuppression for transplant recipients. It is now 60 years since the first demonstration of immunological tolerance in animal models of transplantation, but translation into routine clinical practice remains elusive. Helminth parasites may provide novel strategies toward achieving this goal. Helminths are remarkably successful parasites: they currently infect more than one quarter of the world's population. It is now well established that the parasites' success is the result of active immunomodulation of their hosts' immune response. Although this primarily secures ongoing survival of the parasites, helminth-induced immunomodulation can also have a number of benefits for the host. Significant reductions in the prevalence of allergy and autoimmune conditions among helminth-infected populations are well recognized and there is now a significant body of evidence to suggest that harmful immune responses to alloantigens may be abrogated as well. Here, we review all existing studies of helminth infection and transplantation, explore the mechanisms involved, and discuss possible avenues for future translation to clinical practice.

  1. Ethnopoly promotes tolerance

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    On Friday 23 April, 225 primary school children from the eight schools in Meyrin-Cointrin and their accompanying adults took part in a big game of Ethnopoly. Private individuals, associations, administrations, shopkeepers and CERN all opened their doors to them to talk about their countries, their customs and what they are doing to promote tolerance and integration.   The CERN stand set up at ForumMeyrin for the Ethnopoly game. Scurrying from one place to another, the 10 and 11 year olds were made aware of the rich cultural diversity of their commune, which is home to 130 different nationalities. Physicists and engineers from CERN took up residence in the Forum Meyrin for the day in order to talk to the children about the advantages of international collaboration, a subject dear to the Organization's heart. They welcomed around fifty children in the course of the day, conveying to them a message of tolerance: despite their differences, the 10,000 scientists and other members of the CERN...

  2. The myth of secular tolerance

    Directory of Open Access Journals (Sweden)

    John Coffey

    2011-07-01

    Full Text Available The resurgence of religious violence at the start of the twenty-first century has reinforced the myth of secular tolerance – the notion that whereas religious believers are instinctively intolerant, tolerance comes naturally to the secular mind. This article challenges the myth. It suggests that secular people are not immune from the temptation to persecute and vilify others, and argues that the Christian Gospel fostered the rise of religious toleration. Facing the rise ‘new secularism’ since 2008 it is important to go to the roots of the myth of secular tolerance.

  3. Temperature tolerance and stress proteins as mechanisms of invasive species success.

    Directory of Open Access Journals (Sweden)

    Robyn A Zerebecki

    2011-04-01

    Full Text Available Invasive species are predicted to be more successful than natives as temperatures increase with climate change. However, few studies have examined the physiological mechanisms that theoretically underlie this differential success. Because correlative evidence suggests that invasiveness is related to the width of a species' latitudinal range, it has been assumed--but largely untested--that range width predicts breadth of habitat temperatures and physiological thermotolerances. In this study, we use empirical data from a marine community as a case study to address the hypotheses that (1 geographic temperature range attributes are related to temperature tolerance, leading to greater eurythermality in invasive species, and (2 stress protein expression is a subcellular mechanism that could contribute to differences in thermotolerance. We examined three native and six invasive species common in the subtidal epibenthic communities of California, USA. We assessed thermotolerance by exposing individuals to temperatures between 14°C and 31°C and determining the temperature lethal to 50% of individuals (LT(50 after a 24 hour exposure. We found a strong positive relationship between the LT(50 and both maximum habitat temperatures and the breadth of temperatures experience across the species' ranges. In addition, of the species in our study, invasives tended to inhabit broader habitat temperature ranges and higher maximum temperatures. Stress protein expression may contribute to these differences: the more thermotolerant, invasive species Diplosoma listerianum expressed higher levels of a 70-kDa heat-shock protein than the less thermotolerant, native Distaplia occidentalis for which levels declined sharply above the LT(50. Our data highlight differences between native and invasive species with respect to organismal and cellular temperature tolerances. Future studies should address, across a broader phylogenetic and ecosystem scope, whether this

  4. Variation tolerant SoC design

    Science.gov (United States)

    Kozhikkottu, Vivek J.

    The scaling of integrated circuits into the nanometer regime has led to variations emerging as a primary concern for designers of integrated circuits. Variations are an inevitable consequence of the semiconductor manufacturing process, and also arise due to the side-effects of operation of integrated circuits (voltage, temperature, and aging). Conventional design approaches, which are based on design corners or worst-case scenarios, leave designers with an undesirable choice between the considerable overheads associated with over-design and significantly reduced manufacturing yield. Techniques for variation-tolerant design at the logic, circuit and layout levels of the design process have been developed and are in commercial use. However, with the incessant increase in variations due to technology scaling and design trends such as near-threshold computing, these techniques are no longer sufficient to contain the effects of variations, and there is a need to address variations at all stages of design. This thesis addresses the problem of variation-tolerant design at the earliest stages of the design process, where the system-level design decisions that are made can have a very significant impact. There are two key aspects to making system-level design variation-aware. First, analysis techniques must be developed to project the impact of variations on system-level metrics such as application performance and energy. Second, variation-tolerant design techniques need to be developed to absorb the residual impact of variations (that cannot be contained through lower-level techniques). In this thesis, we address both these facets by developing robust and scalable variation-aware analysis and variation mitigation techniques at the system level. The first contribution of this thesis is a variation-aware system-level performance analysis framework. We address the key challenge of translating the per-component clock frequency distributions into a system-level application

  5. Relationships of self-identified cold tolerance and cold-induced vasodilatation in the finger

    Science.gov (United States)

    Park, Joonhee; Lee, Joo-Young

    2016-04-01

    This study was conducted to investigate relationships of self-identified cold tolerance and cold-induced vasodilatation (CIVD) in the finger. Nine males and 34 females participated in the following 2 tests: a CIVD test and a self-reported survey. The CIVD test was conducted 30-min cold-water immersion (3.8 ± 0.3 °C) of the middle finger at an air temperature of 27.9 ± 0.1 °C. The self-reported questionnaire consisted of 28 questions about whole and local body cold and heat tolerances. By a cluster analysis on the survey results, the participants were divided into two groups: high self-identified cold tolerance (HSCT, n = 25) and low self-identified cold tolerance (LSCT, n = 18). LSCT had lower self-identified cold tolerance ( P physiological cold tolerance.

  6. Adaptive tolerance to phenolic biocides in bacteria from organic foods: Effects on antimicrobial susceptibility and tolerance to physical stresses.

    Science.gov (United States)

    Gadea, Rebeca; Fernández Fuentes, Miguel Ángel; Pérez Pulido, Rubén; Gálvez, Antonio; Ortega, Elena

    2016-07-01

    The aim of the present study was to analyze the effects of step-wise exposure of biocide-sensitive bacteria from organic foods to phenolic biocides triclosan (TC) and hexachlorophene [2,2'-methylenebis(3,4,6-trichlorophenol)] (CF). The analysis included changes in the tolerance to the biocide itself, the tolerance to other biocides, and cross-resistance to clinically important antibiotics. The involvement of efflux mechanisms was also studied as well as the possible implication of modifications in cytoplasmic membrane fluidity in the resistance mechanisms. The influence of biocide tolerance on growth capacity of the adapted strains and on subsequent resistance to other physical stresses has also been analyzed. Repeated exposure of bacteria from organic foods to phenolic biocides resulted in most cases in partially increased tolerance to the same biocide, to dissimilar biocides and other antimicrobial compounds. Nine TC-adapted strains and six CF-adapted strains were able to develop high levels of biocide tolerance, and these were stable in the absence of biocide selective pressure. Most strains adapted to TC and one CF-adapted strain showed significantly higher anisotropy values than their corresponding wildtype strains, suggesting that changes in membrane fluidity could be involved in biocide adaptation. Exposure to gradually increasing concentrations of CF induced a decrease in heat tolerance. Biocide adaptation had no significant effects of gastric acid or bile resistance, suggesting that biocide adaptation should not influence survival in the gastrointestinal tract. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Heat exchanger

    International Nuclear Information System (INIS)

    Bennett, J.C.

    1975-01-01

    A heat exchanger such as forms, for example, part of a power steam boiler is made up of a number of tubes that may be arranged in many different ways, and it is necessary that the tubes be properly supported. The means by which the tubes are secured must be as simple as possible so as to facilitate construction and must be able to continue to function effectively under the varying operating conditions to which the heat exchanger is subject. The arrangement described is designed to meet these requirements, in an improved way. The tubes are secured to a member extending past several tubes and abutment means are provided. At least some of the abutment means comprise two abutment pieces and a wedge secured to the supporting member, that acts on these pieces to maintain the engagement. (U.K.)

  8. Geothermal heat can cool, too

    International Nuclear Information System (INIS)

    Wellstein, J.

    2008-01-01

    This article takes a look at how geothermal energy can not only be used to supply heating energy, but also be used to provide cooling too. The article reports on a conference on heating and cooling with geothermal energy that was held in Duebendorf, Switzerland, in March 2008. The influence of climate change on needs for heating and cooling and the need for additional knowledge and data on deeper rock layers is noted. The seasonal use of geothermal systems to provide heating in winter and cooling in summer is discussed. The planning of geothermal probe fields and their simulation is addressed. As an example, the geothermal installations under the recently renewed and extended 'Dolder Grand' luxury hotel in Zurich are quoted. The new SIA 384/6 norm on geothermal probes issued by the Swiss Association of Architects SIA is briefly reviewed.

  9. Physiological and proteome studies of responses to heat stress during grain filling in contrasting wheat cultivars

    DEFF Research Database (Denmark)

    Wang, Xiao; Dinler, Burcu Seckin; Vignjevic, Marija

    2015-01-01

    Experiments to explore physiological and biochemical differences of the effects of heat stress in ten wheat (Triticum aestivum L) cultivars have been performed. Based on the response of photosynthesis rates, cell membrane lipid peroxide concentrations and grain yield to heat, six cultivars were...... compared to sensitive cultivars under heat stress. The tolerant cv. '810' and the sensitive cv. '1039' were selected for further proteome analysis of leaves. Proteins related to photosynthesis, glycolysis, stress defence, heat shock and ATP production were differently expressed in leaves of the tolerant...... and sensitive cultivar under heat stress in relation to the corresponding control. The abundance of proteins related to signal transduction, heat shock, photosynthesis, and antioxidants increased, while the abundance of proteins related to nitrogen metabolism decreased in the tolerant cv. '810' under heat...

  10. Delay tolerant networks

    CERN Document Server

    Gao, Longxiang; Luan, Tom H

    2015-01-01

    This brief presents emerging and promising communication methods for network reliability via delay tolerant networks (DTNs). Different from traditional networks, DTNs possess unique features, such as long latency and unstable network topology. As a result, DTNs can be widely applied to critical applications, such as space communications, disaster rescue, and battlefield communications. The brief provides a complete investigation of DTNs and their current applications, from an overview to the latest development in the area. The core issue of data forward in DTNs is tackled, including the importance of social characteristics, which is an essential feature if the mobile devices are used for human communication. Security and privacy issues in DTNs are discussed, and future work is also discussed.

  11. Heat-Exchanger/Heat-Pipe Interface

    Science.gov (United States)

    Snyder, H. J.; Van Hagan, T. H.

    1987-01-01

    Monolithic assembly reliable and light in weight. Heat exchanger and evaporator ends of heat pipes integrated in monolithic halves welded together. Interface assembly connects heat exchanger of furnace, reactor, or other power source with heat pipes carrying heat to radiator or power-consuming system. One of several concepts proposed for nuclear power supplies aboard spacecraft, interface useful on Earth in solar thermal power systems, heat engines, and lightweight cooling systems.

  12. Tolerance Issue in Kazakh Culture

    Science.gov (United States)

    Aubakirova, Saltanat S.; Ismagambetova, Zukhra N.; Karabayeva, Aliya G.; Rysbekova, Shamshiya S.; Mirzabekova, Alma Sh.

    2016-01-01

    In this article the authors reveal the basic cultural mechanisms that influence the formation of the tolerance strategy in Kazakh and Kazakhstan society, show its basic directions, as well as its importance for the modern Kazakhstan society and the formation of intercultural communication with foreign countries. Tolerance is a necessary element of…

  13. A Multirelational Account of Toleration

    DEFF Research Database (Denmark)

    Ferretti, Maria Paola; Lægaard, Sune

    2013-01-01

    be understood purely attitudinally or purely politically, we argue that the components of classical toleration are crucial elements of contemporary cases of minority accommodation. The concept of toleration is applicable to, and is an important element of descriptions of such cases, provided that one views them...

  14. Legal Quality, Inequality, and Tolerance

    DEFF Research Database (Denmark)

    Bjørnskov, Christian

    Previous findings suggest that income inequality leads to lower legal quality. This paper argues that voters' tolerance of inequality exerts an additional influence. Empirical findings suggest that inequality leads to lower legal quality due to its effect on trust while the tolerance of inequality...

  15. Hidden Benefits of Electric Vehicles for Addressing Climate Change

    Science.gov (United States)

    Li, Canbing; Cao, Yijia; Zhang, Mi; Wang, Jianhui; Liu, Jianguo; Shi, Haiqing; Geng, Yinghui

    2015-03-01

    There is an increasingly hot debate on whether the replacement of conventional vehicles (CVs) by electric vehicles (EVs) should be delayed or accelerated since EVs require higher cost and cause more pollution than CVs in the manufacturing process. Here we reveal two hidden benefits of EVs for addressing climate change to support the imperative acceleration of replacing CVs with EVs. As EVs emit much less heat than CVs within the same mileage, the replacement can mitigate urban heat island effect (UHIE) to reduce the energy consumption of air conditioners, benefitting local and global climates. To demonstrate these effects brought by the replacement of CVs by EVs, we take Beijing, China, as an example. EVs emit only 19.8% of the total heat emitted by CVs per mile. The replacement of CVs by EVs in 2012 could have mitigated the summer heat island intensity (HII) by about 0.94°C, reduced the amount of electricity consumed daily by air conditioners in buildings by 14.44 million kilowatt-hours (kWh), and reduced daily CO2 emissions by 10,686 tonnes.

  16. Hidden benefits of electric vehicles for addressing climate change.

    Science.gov (United States)

    Li, Canbing; Cao, Yijia; Zhang, Mi; Wang, Jianhui; Liu, Jianguo; Shi, Haiqing; Geng, Yinghui

    2015-03-19

    There is an increasingly hot debate on whether the replacement of conventional vehicles (CVs) by electric vehicles (EVs) should be delayed or accelerated since EVs require higher cost and cause more pollution than CVs in the manufacturing process. Here we reveal two hidden benefits of EVs for addressing climate change to support the imperative acceleration of replacing CVs with EVs. As EVs emit much less heat than CVs within the same mileage, the replacement can mitigate urban heat island effect (UHIE) to reduce the energy consumption of air conditioners, benefitting local and global climates. To demonstrate these effects brought by the replacement of CVs by EVs, we take Beijing, China, as an example. EVs emit only 19.8% of the total heat emitted by CVs per mile. The replacement of CVs by EVs in 2012 could have mitigated the summer heat island intensity (HII) by about 0.94°C, reduced the amount of electricity consumed daily by air conditioners in buildings by 14.44 million kilowatt-hours (kWh), and reduced daily CO2 emissions by 10,686 tonnes.

  17. Heating systems for heating subsurface formations

    Science.gov (United States)

    Nguyen, Scott Vinh [Houston, TX; Vinegar, Harold J [Bellaire, TX

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  18. Toleration, Synthesis or Replacement?

    DEFF Research Database (Denmark)

    Holtermann, Jakob v. H.; Madsen, Mikael Rask

    2016-01-01

    One of the most striking trends in contemporary IL scholarship is the turn to empirical research methods. Some see this as sign of progress, whereas others call for caution or even show hostility. With a view to the future of IL scholarship, however, all sides in this at times heated debate seem...... to have considerable problems keeping a clear focus on the key question: What are the implications of this empirical turn in terms of philosophy of legal science, of the social understanding of IL, and, not least, of the place of doctrinal scholarship after the alleged Wende? What is needed, we argue...

  19. Glucose tolerance test - non-pregnant

    Science.gov (United States)

    Oral glucose tolerance test - non-pregnant; OGTT - non-pregnant; Diabetes - glucose tolerance test; Diabetic - glucose tolerance test ... The most common glucose tolerance test is the oral glucose tolerance test (OGTT). Before the test begins, a sample of blood will be ...

  20. Mapping QTLs associated to germination stability following dry-heat treatment in rice seed.

    Science.gov (United States)

    Lee, Seung-Yeob; Kim, Yong-Hwan; Lee, Gang-Seob

    2017-07-01

    Using 164 recombinant inbred lines (RILs) derived from a cross between Milyang 23 (indica/japonica) and Gihobyeo (japonica) in rice, dry-heat tolerance was evaluated for the seeds of parents and RILs, whose dormancy was naturally broken in six months after harvesting. Mapping QTLs associated to dry-heat tolerance was carried out through interval mapping using Qgene 3.0. Seed germination after dry-heat treatments (90 °C for 24 h) showed a significant difference between the two parents, when evaluated for percentage germination and mean germination time. Milyang 23 was highly tolerant to the dry-heat treatment, while Gihobyeo was sensitive. Three QTLs (qDHT 1, qDHT 5, and qDHT 7) conferring the dry-heat tolerance were mapped to chromosomes 1, 5 and 7, respectively. qDHT 1 on chromosome 1 was tightly linked at 4 cM from ME1-1. The phenotypic variation explained by the three QTLs was 27.18% of the total variance in the 164 RIL populations, and the parental additive effects of three QTLs affected the Milyang 23 allele increased dry-heat tolerance. The detection of new QTLs associated with dry-heat tolerance will provide important information for disease and insect control, using dry-heat treatment in organic or low input sustainable agriculture.

  1. Cell motility and antibiotic tolerance of bacterial swarms

    Science.gov (United States)

    Zuo, Wenlong

    Many bacteria species can move across moist surfaces in a coordinated manner known as swarming. It is reported that swarm cells show higher tolerance to a wide variety of antibiotics than planktonic cells. We used the model bacterium E. coli to study how motility affects the antibiotic tolerance of swarm cells. Our results provide new insights for the control of pathogenic invasion via regulating cell motility. Mailing address: Room 306 Science Centre North Block, The Chinese University of Hong Kong, Shatin, N.T. Hong Kong SAR. Phone: +852-3943-6354. Fax: +852-2603-5204. E-mail: zwlong@live.com.

  2. 77 FR 48429 - Commission Address Change

    Science.gov (United States)

    2012-08-14

    ... Commission Address Change AGENCY: Federal Mine Safety and Health Review Commission (FMSHRC). ACTION: Final... office and is amending its regulations to inform the public of the address change. DATES: This final rule... dealing with only a change in address. The Commission is an independent regulatory agency and, as such, is...

  3. 33 CFR 135.9 - Fund address.

    Science.gov (United States)

    2010-07-01

    ... FINANCIAL RESPONSIBILITY AND COMPENSATION OFFSHORE OIL POLLUTION COMPENSATION FUND General § 135.9 Fund address. The address to which correspondence relating to the Coast Guard's administration of the Fund... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Fund address. 135.9 Section 135.9...

  4. Heat exchanger

    International Nuclear Information System (INIS)

    Dostatni, A.W.; Dostatni, Michel.

    1976-01-01

    In the main patent, a description was given of a heat exchanger with an exchange surface in preformed sheet metal designed for the high pressure and temperature service particularly encountered in nuclear pressurized water reactors and which is characterised by the fact that it is composed of at least one exchanger bundle sealed in a containment, the said bundle or bundles being composed of numerous juxtaposed individual compartments whose exchange faces are built of preformed sheet metal. The present addendun certificate concerns shapes of bundles and their positioning methods in the exchanger containment enabling its compactness to be increased [fr

  5. Heat pipes

    CERN Document Server

    Dunn, Peter D

    1982-01-01

    A comprehensive, up-to-date coverage of the theory, design and manufacture of heat pipes and their applications. This latest edition has been thoroughly revised, up-dated and expanded to give an in-depth coverage of the new developments in the field. Significant new material has been added to all the chapters and the applications section has been totally rewritten to ensure that topical and important applications are appropriately emphasised. The bibliography has been considerably enlarged to incorporate much valuable new information. Thus readers of the previous edition, which has established

  6. Heat-Related Illnesses

    Medline Plus

    Full Text Available ... Emergencies A-Z Share this! Home » Emergency 101 Heat-Related Illnesses Dr. Glenn Mitchell , Emergency physician at ... about heat cramps and heat stroke and exhaustion. Heat Cramps Symptoms include muscle spasms, usually in the ...

  7. Radiofrequency plasma heating: proceedings

    International Nuclear Information System (INIS)

    Swenson, D.G.

    1985-01-01

    The conference proceedings include sessions on Alfven Wave Heating, ICRF Heating and Current Drive, Lower Hybrid Heating and Current Drive, and ECRF Heating. Questions of confinement, diagnostics, instabilities and technology are considered. Individual papers are cataloged separately

  8. Low temperature nuclear heat

    Energy Technology Data Exchange (ETDEWEB)

    Kotakorpi, J.; Tarjanne, R. (comps.)

    1977-08-01

    The meeting was concerned with the use of low grade nuclear heat for district heating, desalination, process heat, and agriculture and aquaculture. The sessions covered applications and demand, heat sources, and economics.

  9. Recent Advances in Durability and Damage Tolerance Methodology at NASA Langley Research Center

    Science.gov (United States)

    Ransom, J. B.; Glaessgen, E. H.; Raju, I. S.; Harris, C. E.

    2007-01-01

    Durability and damage tolerance (D&DT) issues are critical to the development of lighter, safer and more efficient aerospace vehicles. Durability is largely an economic life-cycle design consideration whereas damage tolerance directly addresses the structural airworthiness (safety) of the vehicle. Both D&DT methodologies must address the deleterious effects of changes in material properties and the initiation and growth of damage that may occur during the vehicle s service lifetime. The result of unanticipated D&DT response is often manifested in the form of catastrophic and potentially fatal accidents. As such, durability and damage tolerance requirements must be rigorously addressed for commercial transport aircraft and NASA spacecraft systems. This paper presents an overview of the recent and planned future research in durability and damage tolerance analytical and experimental methods for both metallic and composite aerospace structures at NASA Langley Research Center (LaRC).

  10. Physiological effects after exposure to heat : A brief literature review

    NARCIS (Netherlands)

    Bogerd, C.P.; Daanen, H.A.M.

    2011-01-01

    Many employees are exposed to heat stress during their work. Although the direct effects of heat are well reported, the long term physiological effects occurring after heat exposure are hardly described. The present manuscript addresses these issues in the form of a brief literature review. Repeated

  11. Heat Transfer in Glass, Aluminum, and Plastic Beverage Bottles

    Science.gov (United States)

    Clark, William M.; Shevlin, Ryan C.; Soffen, Tanya S.

    2010-01-01

    This paper addresses a controversy regarding the effect of bottle material on the thermal performance of beverage bottles. Experiments and calculations that verify or refute advertising claims and represent an interesting way to teach heat transfer fundamentals are described. Heat transfer coefficients and the resistance to heat transfer offered…

  12. A novel electron gun with an independently addressable cathode array

    Energy Technology Data Exchange (ETDEWEB)

    Rudys, Joseph Matthew; Reed, Kim Warren; Pena, Gary Edward; Schneider, Larry X.

    2006-08-01

    The design of a novel electron gun with an array of independently addressable cathode elements is presented. Issues relating to operation in a 6.5 Tesla axial magnetic field are discussed. Simulations with the TriComp electromagnetic field code that were used to determine the space charge limited tube characteristic and to model focusing of the electron beam in the magnetic field are reviewed. Foil heating and stress calculations are discussed. The results of CYLTRAN simulations yielding the energy spectrum of the electron beam and the current transmitted through the foil window are presented.

  13. Hovering in the heat: effects of environmental temperature on heat regulation in foraging hummingbirds.

    Science.gov (United States)

    Powers, Donald R; Langland, Kathleen M; Wethington, Susan M; Powers, Sean D; Graham, Catherine H; Tobalske, Bret W

    2017-12-01

    At high temperature (greater than 40°C) endotherms experience reduced passive heat dissipation (radiation, conduction and convection) and increased reliance on evaporative heat loss. High temperatures challenge flying birds due to heat produced by wing muscles. Hummingbirds depend on flight for foraging, yet inhabit hot regions. We used infrared thermography to explore how lower passive heat dissipation during flight impacts body-heat management in broad-billed ( Cynanthus latirostris , 3.0 g), black-chinned ( Archilochus alexandri , 3.0 g), Rivoli's ( Eugenes fulgens , 7.5 g) and blue-throated ( Lampornis clemenciae , 8.0 g) hummingbirds in southeastern Arizona and calliope hummingbirds ( Selasphorus calliope , 2.6 g) in Montana. Thermal gradients driving passive heat dissipation through eye, shoulder and feet dissipation areas are eliminated between 36 and 40°C. Thermal gradients persisted at higher temperatures in smaller species, possibly allowing them to inhabit warmer sites. All species experienced extended daytime periods lacking thermal gradients. Broad-billed hummingbirds lacking thermal gradients regulated the mean total-body surface temperature at approximately 38°C, suggesting behavioural thermoregulation. Blue-throated hummingbirds were inactive when lacking passive heat dissipation and hence might have the lowest temperature tolerance of the four species. Use of thermal refugia permitted hummingbirds to tolerate higher temperatures, but climate change could eliminate refugia, forcing distributional shifts in hummingbird populations.

  14. Multi-level interactions between HEAT SHOCK FACTORS, HEAT SHOCK PROTEINS and the redox system regulate acclimation to heat

    Directory of Open Access Journals (Sweden)

    Nicky eDriedonks

    2015-11-01

    Full Text Available High temperature has become a global concern because it seriously affects the growth and reproduction of plants. Exposure of plant cells to high temperatures result in cellular damage and can even lead to cell death. Part of the damage can be ascribed to the action of reactive oxygen species (ROS, which accumulate during abiotic stresses such as heat stress. ROS are toxic and can modify other biomacromolecules including membrane lipids, DNA and proteins. In order to protect the cells, ROS scavenging is essential. In contrast with their inherent harms, ROS also function as signaling molecules, inducing stress tolerance mechanisms. This review examines the evidence for crosstalk between the classical heat stress response, which consists of HEAT SHOCK FACTORS (HSFs and HEAT SHOCK PROTEINS (HSPs, with the ROS network at multiple levels in the heat response process. Heat stimulates HSF activity directly, but also indirectly via ROS. HSFs in turn stimulate the expression of HSP chaperones and also affect ROS scavenger gene expression. In the short term, HSFs repress expression of superoxide dismutase scavenger genes via induction of miRNA398, while they also activate scavenger gene expression and stabilize scavenger protein activity via HSP induction. We propose that these contrasting effects allow for the boosting of the heat stress response at the very onset of the stress, while preventing subsequent oxidative damage. The described model on HSFs, HSPs, ROS and ROS scavenger interactions seems applicable to responses to stresses other than heat and may explain the phenomenon of cross-acclimation.

  15. Segmented heat exchanger

    Science.gov (United States)

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  16. Heat Rejection Systems Utilizing Composites and Heat Pipes: Design and Performance Testing

    Science.gov (United States)

    Jaworske, Donald A.; Beach, Duane E.; Sanzi, James L.

    2007-01-01

    Polymer matrix composites offer the promise of reducing the mass and increasing the performance of future heat rejection systems. With lifetimes for heat rejection systems reaching a decade or more in a micrometeoroid environment, use of multiple heat pipes for fault tolerant design is compelling. The combination of polymer matrix composites and heat pipes is of particular interest for heat rejection systems operating on the lunar surface. A technology development effort is under way to study the performance of two radiator demonstration units manufactured with different polymer matrix composite face sheet resin and bonding adhesives, along with different titanium-water heat pipe designs. Common to the two radiator demonstration units is the use of high thermal conductivity fibers in the face sheets and high thermal conductivity graphite saddles within a light weight aluminum honeycomb core. Testing of the radiator demonstration units included thermal vacuum exposure and thermal vacuum exposure with a simulated heat pipe failure. Steady state performance data were obtained at different operating temperatures to identify heat transfer and thermal resistance characteristics. Heat pipe failure was simulated by removing the input power from an individual heat pipe in order to identify the diminished performance characteristics of the entire panel after a micrometeoroid strike. Freeze-thaw performance was also of interest. This paper presents a summary of the two radiator demonstration units manufactured to support this technology development effort along with the thermal performance characteristics obtained to date. Future work will also be discussed.

  17. Anhydrobiosis and Freezing-Tolerance

    DEFF Research Database (Denmark)

    McGill, Lorraine; Shannon, Adam; Pisani, Davide

    2015-01-01

    Panagrolaimus strains from tropical, temperate, continental and polar habitats and we analysed their phylogenetic relationships. We found that several other Panagrolaimus isolates can also survive freezing when fully hydrated and that tissue extracts from these freezing-tolerant nematodes can inhibit the growth...... Pennsylvania, USA. Ancestral state reconstructions show that anhydrobiosis evolved deep in the phylogeny of Panagrolaimus. The early-diverging Panagrolaimus lineages are strongly anhydrobiotic but weakly freezing-tolerant, suggesting that freezing tolerance is most likely a derived trait. The common ancestors...

  18. Mechanical tolerance stackup and analysis

    CERN Document Server

    Fischer, Bryan R

    2011-01-01

    Use Tolerance Analysis Techniques to Avoid Design, Quality, and Manufacturing Problems Before They Happen Often overlooked and misunderstood, tolerance analysis is a critical part of improving products and their design processes. Because all manufactured products are subject to variation, it is crucial that designers predict and understand how these changes can affect form, fit, and function of parts and assemblies--and then communicate their findings effectively. Written by one of the developers of ASME Y14.5 and other geometric dimension and tolerancing (GD&T) standards, Mechanical Tolerance

  19. Advanced cloud fault tolerance system

    Science.gov (United States)

    Sumangali, K.; Benny, Niketa

    2017-11-01

    Cloud computing has become a prevalent on-demand service on the internet to store, manage and process data. A pitfall that accompanies cloud computing is the failures that can be encountered in the cloud. To overcome these failures, we require a fault tolerance mechanism to abstract faults from users. We have proposed a fault tolerant architecture, which is a combination of proactive and reactive fault tolerance. This architecture essentially increases the reliability and the availability of the cloud. In the future, we would like to compare evaluations of our proposed architecture with existing architectures and further improve it.

  20. The culture of tolerance in diverse societies: Reasonable toleration

    OpenAIRE

    Mckinnon, Catriona; Castiglione, Dario

    2003-01-01

    The idea of toleration as the appropriate response to difference has been central to liberal thought since Locke. Although the subject has been widely and variously explored, there has been reluctance to acknowledge the new meaning that current debates on toleration have when compared with those at its origins in the early modern period and with subsequent discussions about pluralism and freedom of expression. This collection starts from a clear recognition of the new terms of the debate. It ...

  1. Tolerance to and cross tolerance between ethanol and nicotine.

    Science.gov (United States)

    Collins, A C; Burch, J B; de Fiebre, C M; Marks, M J

    1988-02-01

    Female DBA mice were subjected to one of four treatments: ethanol-containing or control diets, nicotine (0.2, 1.0, 5.0 mg/kg/hr) infusion or saline infusion. After removal from the liquid diets or cessation of infusion, the animals were challenged with an acute dose of ethanol or nicotine. Chronic ethanol-fed mice were tolerant to the effects of ethanol on body temperature and open field activity and were cross tolerant to the effects of nicotine on body temperature and heart rate. Nicotine infused animals were tolerant to the effects of nicotine on body temperature and rotarod performance and were cross tolerant to the effects of ethanol on body temperature. Ethanol-induced sleep time was decreased in chronic ethanol- but not chronic nicotine-treated mice. Chronic drug treatment did not alter the elimination rate of either drug. Chronic ethanol treatment did not alter the number or affinity of brain nicotinic receptors whereas chronic nicotine treatment elicited an increase in the number of [3H]-nicotine binding sites. Tolerance and cross tolerance between ethanol and nicotine is discussed in terms of potential effects on desensitization of brain nicotinic receptors.

  2. Accident tolerant fuel analysis

    International Nuclear Information System (INIS)

    2014-01-01

    Safety is central to the design, licensing, operation, and economics of Nuclear Power Plants (NPPs). Consequently, the ability to better characterize and quantify safety margin holds the key to improved decision making about light water reactor design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margins management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway research and development (R&D) is to support plant decisions for risk-informed margins management by improving economics and reliability, and sustaining safety, of current NPPs. Goals of the RISMC Pathway are twofold: (1) Develop and demonstrate a risk-assessment method coupled to safety margin quantification that can be used by NPP decision makers as part of their margin recovery strategies. (2) Create an advanced ''RISMC toolkit'' that enables more accurate representation of NPP safety margin. In order to carry out the R&D needed for the Pathway, the Idaho National Laboratory is performing a series of case studies that will explore methods- and tools-development issues, in addition to being of current interest in their own right. One such study is a comparative analysis of safety margins of plants using different fuel cladding types: specifically, a comparison between current-technology Zircaloy cladding and a notional ''accident-tolerant'' (e.g., SiC-based) cladding. The present report begins the process of applying capabilities that are still under development to the problem of assessing new fuel designs. The approach and lessons learned from this case study will be included in future Technical Basis Guides produced by the RISMC Pathway. These guides will be the mechanism for developing the specifications for RISMC tools and for defining how plant

  3. Autonomous Congestion Control in Delay-Tolerant Networks

    Science.gov (United States)

    Burleigh, Scott; Jennings, Esther; Schoolcraft, Joshua

    2006-01-01

    This presentation highlights communication congestion control in delay-tolerant networks (DTNs). Large-scale future space exploration will offer complex communication challenges that may be best addressed by establishing a network infrastructure. However, current internet techniques for congestion control are not well suited for operation of a network over interplanetary distances. An alternative, delay-tolerant technique for congestion control in a delay-tolerant network is presented. A simple DTN was constructed and an experimental congestion control mechanism was applied. The mechanism appeared to be effective and each router was able to make its bundle acceptance decisions autonomously. Future research will examine more complex topologies and alternative bundle acceptance rules that might enhance performance.

  4. Experimental study of heat transfer in a heat exchanger with rectangular channels

    International Nuclear Information System (INIS)

    Hammami, Mahmoud; Ben Said, Akrem; Ben Maad, Rejeb; Rebay, Mourad

    2009-01-01

    This paper presents the results of an experimental study related to characterisation of a mini channel heat exchanger. Such heat exchanger may be used in water cooling of electronic components. The results obtained show the efficiency of this exchanger even with very low water flow rates. Indeed, in spite of the importance of the extracted heat fluxes which can reach about 50Kw/m 2 , the temperature of the cooled Aluminium bloc remained always lower than the tolerated threshold of 80 degree in electronic cooling. Moreover, several thermal characteristics such as equivalent thermal resistance of the exchanger, the average internal convective heat transfer coefficient and the increase in the temperature of the cooling water have been measured. The results presented have been obtained with in q uinconce r ectangular mini-channel heat exchanger, with a hydraulic diameter D h = 2mm. NOMENCLATURE h D Hydraulic diameter (mm). int

  5. Acquisition of tolerance against oxidative damage in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Eleutherio Elis CA

    2001-07-01

    Full Text Available Abstract Background Living cells constantly sense and adapt to redox shifts by the induction of genes whose products act to maintain the cellular redox environment. In the eukaryote Saccharomyces cerevisiae, while stationary cells possess a degree of constitutive resistance towards oxidants, treatment of exponential phase cultures with sub-lethal stresses can lead to the transient induction of protection against subsequent lethal oxidant conditions. The sensors of oxidative stress and the corresponding transcription factors that activate gene expression under these conditions have not yet been completely identified. Results We report the role of SOD1, SOD2 and TPS1 genes (which encode the cytoplasmic Cu/Zn-superoxide dismutase, the mitochondrial Mn-isoform and trehalose-6-phosphate synthase, respectively in the development of resistance to oxidative stress. In all experimental conditions, the cultures were divided into two parts, one was immediately submitted to severe stress (namely: exposure to H2O2, heat shock or ethanol stress while the other was initially adapted to 40°C for 60 min. The deficiency in trehalose synthesis did not impair the acquisition of tolerance to H2O2, but this disaccharide played an essential role in tolerance against heat and ethanol stresses. We also verified that the presence of only one Sodp isoform was sufficient to improve cellular resistance to 5 mM H2O2. On the other hand, while the lack of Sod2p caused high cell sensitivity to ethanol and heat shock, the absence of Sod1p seemed to be beneficial to the process of acquisition of tolerance to these adverse conditions. The increase in oxidation-dependent fluorescence of crude extracts of sod1 mutant cells upon incubation at 40°C was approximately 2-fold higher than in sod2 and control strain extracts. Furthermore, in Western blots, we observed that sod mutants showed a different pattern of Hsp104p and Hsp26p expression also different from that in their control

  6. Produtividade de genótipos de batata inglesa tolerantes ao calor em duas épocas de plantio, no vale do São Francisco Productivity of heat tolerant potato genotypes in two planting times in São Francisco Valley, Northeast of Brazil

    Directory of Open Access Journals (Sweden)

    José Egídio Flori

    2000-07-01

    Full Text Available Com o objetivo de avaliar diferentes genótipos de batata tolerantes ao calor em duas épocas de plantio (inverno e primavera, instalaram-se dois experimentos no Campo Experimental de Bebedouro da Embrapa Semi-Árido, Petrolina (PE. O delineamento experimental foi blocos ao acaso com quatro repetições, utilizando-se os genótipos LT-9, 301251-1, 311320-1, 301217-1, 301159-1, Serrana x DTO-33 e a variedade comercial Baraka como testemunha. Na condição de clima quente (média de 25,8°C, o genótipo LT-9 apresentou a maior produtividade comercial (10,3 t/ha, seguido pelos demais tratamentos que não mostraram diferenças estatísticas entre si, à exceção de Serrana x DTO-33 que apresentou a menor produtividade (2,7 t/ha. O cultivo na condição de clima mais frio (média de 24,7°C, a produtividade total variou de 17,5 t/ha a 23,3 t/ha, sendo que o genótipo 301251-1 alcançou a maior produtividade (23,3 t/ha, não se verificando diferença estatística entre os tratamentos. Pelos resultados preliminares obtidos há indicação que os genótipos 301251-1, 311320-1; 301217-1 e 301159-1 podem ser plantados de abril a agosto como alternativas de cultivo à cultivar Baraka, necessitando, porém, de maiores investigações.The experiments were carried out at the Bebedouro Experimental Field of Embrapa Semi-Àrid Research Center in Petrolina, Brazil, to evaluate different heat tolerant potato genotypes under two climatic conditions. The experimental design was of randomized complete blocks with seven genotypes (LT-9, 301251-1, 311320-1, 301217-1, 301159-1, Serrana x DTO-33 and cv. Baraka and four replications. Under hot climatic condition (28°C the genotype LT-9 showed the highest commercial yield (10.3 t/ha, followed by the other treatments that didn't show statistical differences in relation to each other, except the genotype Serrana x DTO-33 which showed the lowest commercial yield (2.7 t/ha. Under favorable condition (23°C, the commercial

  7. Organization of Control Units with Operational Addressing

    OpenAIRE

    Alexander A. Barkalov; Roman M. Babakov; Larysa A. Titarenko

    2012-01-01

    The using of operational addressing unit as the block of control unit is proposed. The new structure model of Moore finite-state machine with reduced hardware amount is developed. The generalized structure of operational addressing unit is suggested. An example of synthesis process for Moore finite-state machine with operational addressing unit is given. The analytical researches of proposed structure of control unit are executed.

  8. Cytokine regulation of immune tolerance

    OpenAIRE

    Wu, Jie; Xie, Aini; Chen, Wenhao

    2014-01-01

    The immune system provides defenses against invading pathogens while maintaining immune tolerance to self-antigens. This immune homeostasis is harmonized by the direct interactions between immune cells and the cytokine environment in which immune cells develop and function. Herein, we discuss three non-redundant paradigms by which cytokines maintain or break immune tolerance. We firstly describe how anti-inflammatory cytokines exert direct inhibitory effects on immune cells to enforce immune ...

  9. Shaping tolerant attitudes towards immigrants

    DEFF Research Database (Denmark)

    Rapp, Carolin

    2017-01-01

    civil societies cope with rising levels of diversity stemming from increased immigration and individualism. Within the tolerance literature, it is commonly agreed upon that a comprehensive welfare state is capable of bridging class divides and overcoming social categorization. However, over the past...... decades, European welfare states experienced an ongoing influx of immigrants, challenging their general purpose and increasing notions of ‘welfare chauvinism’. Drawing on insights from both tolerance and welfare state solidarity literature, we implement hierarchical analyses based on Eurobarometer data...

  10. Novel Duplicate Address Detection with Hash Function.

    Directory of Open Access Journals (Sweden)

    GuangJia Song

    Full Text Available Duplicate address detection (DAD is an important component of the address resolution protocol (ARP and the neighbor discovery protocol (NDP. DAD determines whether an IP address is in conflict with other nodes. In traditional DAD, the target address to be detected is broadcast through the network, which provides convenience for malicious nodes to attack. A malicious node can send a spoofing reply to prevent the address configuration of a normal node, and thus, a denial-of-service attack is launched. This study proposes a hash method to hide the target address in DAD, which prevents an attack node from launching destination attacks. If the address of a normal node is identical to the detection address, then its hash value should be the same as the "Hash_64" field in the neighboring solicitation message. Consequently, DAD can be successfully completed. This process is called DAD-h. Simulation results indicate that address configuration using DAD-h has a considerably higher success rate when under attack compared with traditional DAD. Comparative analysis shows that DAD-h does not require third-party devices and considerable computing resources; it also provides a lightweight security resolution.

  11. IP Address Management Principles and Practice

    CERN Document Server

    Rooney, Timothy

    2010-01-01

    This book will be the first covering the subject of IP address management (IPAM). The practice of IPAM includes the application of network management disciplines to IP address space and associated network services, namely DHCP (Dynamic Host Configuration Protocol) and DNS (Domain Name System). The consequence of inaccurately configuring DHCP is that end users may not be able to obtain IP addresses to access the network. Without proper DNS configuration, usability of the network will greatly suffer as the name-to-address lookup process may fail. Imagine having to navigate to a website or send a

  12. Selection of high temperature and salinity tolerant Trichoderma isolates with antagonistic activity against Sclerotium rolfsii

    OpenAIRE

    Poosapati, Sowmya; Ravulapalli, Prasad Durga; Tippirishetty, Navaneetha; Vishwanathaswamy, Dinesh Kumar; Chunduri, Sarada

    2014-01-01

    Trichoderma isolates were collected from varied agro-climatic zones of India and screened for high temperature and salinity tolerance. Among all the isolates tested, T. asperellum, TaDOR673 was highly tolerant to heat shock of 52°C with a mean spore count (log c.f.u/ml) of 4.33. The isolate after recovery from heat shock possessed higher germination rate and biomass production compared to its wild counterpart, upon prolonged exposure to 37°C. Under stress, TaDOR673 accumulated >15% of trehalo...

  13. Compact cryocooler heat exchangers

    International Nuclear Information System (INIS)

    Luna, J.; Frederking, T.H.K.

    1991-01-01

    Compact heat exchangers are subject to different constraints as a room temperature gas is cooled down by a cold stream returning from a JT valve (or a similar cryoprocess component). In particular, the optimization of exchangers for liquid helium systems has to cover a wide range in temperature and density of the fluid. In the present work we address the following thermodynamic questions: 1. The optimization of intermediate temperatures which optimize stage operation (a stage is assumed to have a constant cross section); 2. The optimum temperature difference available for best overall economic performance values. The results are viewed in the context of porous media concepts applied to rather low speeds of fluid flow in narrow passages. In this paper examples of fluid/solid constraints imposed in this non-classical low temperature area are presented

  14. The Metabolic Basis of Pollen Thermo-Tolerance: Perspectives for Breeding

    Directory of Open Access Journals (Sweden)

    Marine J. Paupière

    2014-09-01

    Full Text Available Crop production is highly sensitive to elevated temperatures. A rise of a few degrees above the optimum growing temperature can lead to a dramatic yield loss. A predicted increase of 1–3 degrees in the twenty first century urges breeders to develop thermo-tolerant crops which are tolerant to high temperatures. Breeding for thermo-tolerance is a challenge due to the low heritability of this trait. A better understanding of heat stress tolerance and the development of reliable methods to phenotype thermo-tolerance are key factors for a successful breeding approach. Plant reproduction is the most temperature-sensitive process in the plant life cycle. More precisely, pollen quality is strongly affected by heat stress conditions. High temperature leads to a decrease of pollen viability which is directly correlated with a loss of fruit production. The reduction in pollen viability is associated with changes in the level and composition of several (groups of metabolites, which play an important role in pollen development, for example by contributing to pollen nutrition or by providing protection to environmental stresses. This review aims to underline the importance of maintaining metabolite homeostasis during pollen development, in order to produce mature and fertile pollen under high temperature. The review will give an overview of the current state of the art on the role of various pollen metabolites in pollen homeostasis and thermo-tolerance. Their possible use as metabolic markers to assist breeding programs for plant thermo-tolerance will be discussed.

  15. Proteomics of desiccation tolerance during development and germination of maize embryos.

    Science.gov (United States)

    Huang, Hui; Møller, Ian Max; Song, Song-Quan

    2012-02-02

    Maize seeds were used to identify the key embryo proteins involved in desiccation tolerance during development and germination. Immature maize embryos (28N) during development and mature embryos imbibed for 72 h (72HN) are desiccation sensitive. Mature maize embryos (52N) during development are desiccation tolerant. Thiobarbituric acid reactive substance and hydrogen peroxide contents decreased and increased with acquisition and loss of desiccation tolerance, respectively. A total of 111 protein spots changed significantly (1.5 fold increase/decrease) in desiccation-tolerant and -sensitive embryos before (28N, 52N and 72HN) and after (28D, 52D and 72HD) dehydration. Nine pre-dominantly proteins, 17.4 kDa Class I heat shock protein 3, late embryogenesis abundant protein EMB564, outer membrane protein, globulin 2, TPA:putative cystatin, NBS-LRR resistance-like protein RGC456, stress responsive protein, major allergen Bet v 1.01C and proteasome subunit alpha type 1, accumulated during embryo maturation, decreased during germination and increased in desiccation-tolerant embryos during desiccation. Two proteins, Rhd6-like 2 and low-molecular-weight heat shock protein precursor, showed the inverse pattern. We infer that these eleven proteins are involved in seed desiccation tolerance. We conclude that desiccation-tolerant embryos make more economical use of their resources to accumulate protective molecules and antioxidant systems to deal with maturation drying and desiccation treatment. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Pyruvate Accumulation Is the First Line of Cell Defense against Heat Stress in a Fungus

    OpenAIRE

    Xing Zhang; Raymond J. St. Leger; Weiguo Fang; Michael Lorenz

    2017-01-01

    ABSTRACT Heat tolerance is well known to be key to fungal survival in many habitats, but our mechanistic understanding of how organisms adapt to heat stress is still incomplete. Using Metarhizium robertsii, an emerging model organism for assessing evolutionary processes, we report that pyruvate is in the vanguard of molecules that scavenge heat-induced reactive oxygen species (ROS). We show that, as well as inducing a rapid burst of ROS production, heat stress also downregulates genes for pyr...

  17. Rapid shift in thermal resistance between generations through maternal heat exposure

    NARCIS (Netherlands)

    Zizzari, Z.V.; Ellers, J.

    2014-01-01

    Given the current rapid climate change, understanding the mechanisms underlying heat tolerance and its plasticity is an important goal of global change biology. Soil fauna communities are especially vulnerable because of their limited dispersal ability. It is generally recognized that

  18. Automation of heating system with heat pump

    OpenAIRE

    Ferdin, Gašper

    2016-01-01

    Because of high prices of energy, we are upgrading our heating systems with newer, more fuel efficient heating devices. Each new device has its own control system, which operates independently from other devices in a heating system. With a relatively low investment costs in automation, we can group devices in one central control system and increase the energy efficiency of a heating system. In this project, we show how to connect an oil furnace, a sanitary heat pump, solar panels and a heat p...

  19. Approaches for Resolving Dynamic IP Addressing.

    Science.gov (United States)

    Foo, Schubert; Hui, Siu Cheung; Yip, See Wai; He, Yulan

    1997-01-01

    A problem with dynamic Internet protocol (IP) addressing arises when the Internet connection is through an Internet provider since the IP address is allocated only at connection time. This article examines a number of online and offline methods for resolving the problem. Suggests dynamic domain name system (DNS) and directory service look-up are…

  20. 16 CFR 1000.4 - Commission address.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Commission address. 1000.4 Section 1000.4 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION GENERAL COMMISSION ORGANIZATION AND FUNCTIONS § 1000.4 Commission address. The principal Offices of the Commission are at 4330 East West Highway...

  1. 37 CFR 251.1 - Official addresses.

    Science.gov (United States)

    2010-07-01

    ... Express, United Parcel Service and similar corporate courier services), use the following address... through the U.S. Postal Service, use the following address: Copyright Arbitration Royalty Panel, P.O. Box 70977, Southwest Station, Washington, DC 20024-0977. (d) Federal Express, United Parcel Service and...

  2. Generative Street Addresses from Satellite Imagery

    Directory of Open Access Journals (Sweden)

    İlke Demir

    2018-03-01

    Full Text Available We describe our automatic generative algorithm to create street addresses from satellite images by learning and labeling roads, regions, and address cells. Currently, 75% of the world’s roads lack adequate street addressing systems. Recent geocoding initiatives tend to convert pure latitude and longitude information into a memorable form for unknown areas. However, settlements are identified by streets, and such addressing schemes are not coherent with the road topology. Instead, we propose a generative address design that maps the globe in accordance with streets. Our algorithm starts with extracting roads from satellite imagery by utilizing deep learning. Then, it uniquely labels the regions, roads, and structures using some graph- and proximity-based algorithms. We also extend our addressing scheme to (i cover inaccessible areas following similar design principles; (ii be inclusive and flexible for changes on the ground; and (iii lead as a pioneer for a unified street-based global geodatabase. We present our results on an example of a developed city and multiple undeveloped cities. We also compare productivity on the basis of current ad hoc and new complete addresses. We conclude by contrasting our generative addresses to current industrial and open solutions.

  3. Heat pump technology

    CERN Document Server

    Von Cube, Hans Ludwig; Goodall, E G A

    2013-01-01

    Heat Pump Technology discusses the history, underlying concepts, usage, and advancements in the use of heat pumps. The book covers topics such as the applications and types of heat pumps; thermodynamic principles involved in heat pumps such as internal energy, enthalpy, and exergy; and natural heat sources and energy storage. Also discussed are topics such as the importance of the heat pump in the energy industry; heat pump designs and systems; the development of heat pumps over time; and examples of practical everyday uses of heat pumps. The text is recommended for those who would like to kno

  4. Impact of anthropogenic ocean acidification on thermal tolerance of the spider crab Hyas araneus

    Directory of Open Access Journals (Sweden)

    H. O. Pörtner

    2009-10-01

    Full Text Available Future scenarios for the oceans project combined developments of CO2 accumulation and global warming and their impact on marine ecosystems. The synergistic impact of both factors was addressed by studying the effect of elevated CO2 concentrations on thermal tolerance of the cold-eurythermal spider crab Hyas araneus from the population around Helgoland. Here ambient temperatures characterize the southernmost distribution limit of this species. Animals were exposed to present day normocapnia (380 ppm CO2, CO2 levels expected towards 2100 (710 ppm and beyond (3000 ppm. Heart rate and haemolymph PO2 (PeO2 were measured during progressive short term cooling from 10 to 0°C and during warming from 10 to 25°C. An increase of PeO2 occurred during cooling, the highest values being reached at 0°C under all three CO2 levels. Heart rate increased during warming until a critical temperature (Tc was reached. The putative Tc under normocapnia was presumably >25°C, from where it fell to 23.5°C under 710 ppm and then 21.1°C under 3000 ppm. At the same time, thermal sensitivity, as seen in the Q10 values of heart rate, rose with increasing CO2 concentration in the warmth. Our results suggest a narrowing of the thermal window of Hyas araneus under moderate increases in CO2 levels by exacerbation of the heat or cold induced oxygen and capacity limitation of thermal tolerance.

  5. Heat exposure and socio-economic vulnerability as synergistic factors in heat-wave-related mortality

    International Nuclear Information System (INIS)

    Rey, Gregoire; Fouillet, Anne; Bessemoulin, Pierre; Frayssinet, Philippe; Dufour, Anne; Jougla, Eric; Hemon, Denis

    2009-01-01

    Heat waves may become a serious threat to the health and safety of people who currently live in temperate climates. It was therefore of interest to investigate whether more deprived populations are more vulnerable to heat waves. In order to address the question on a fine geographical scale, the spatial heterogeneity of the excess mortality in France associated with the European heat wave of August 2003 was analysed. A deprivation index and a heat exposure index were used jointly to describe the heterogeneity on the Canton scale (3,706 spatial units). During the heat wave period, the heat exposure index explained 68% of the extra-Poisson spatial variability of the heat wave mortality ratios. The heat exposure index was greater in the most urbanized areas. For the three upper quintiles of heat exposure in the densely populated Paris area, excess mortality rates were twofold higher in the most deprived Cantons (about 20 excess deaths/100,000 people/day) than in the least deprived Cantons (about 10 excess deaths/100,000 people/day). No such interaction was observed for the rest of France, which was less exposed to heat and less heterogeneous in terms of deprivation. Although a marked increase in mortality was associated with heat wave exposure for all degrees of deprivation, deprivation appears to be a vulnerability factor with respect to heat-wave-associated mortality.

  6. Tolerance and acculturation

    Directory of Open Access Journals (Sweden)

    Ursula Småland Goth

    2014-12-01

    study shows a varied pattern of use of GP services among the diverse groups of foreign-born residents. Results suggest that immigrants are more likely to use emergency-room services during the first few years after arrival. Results also indicate that information about the patient-list system does not always reach newly arrived immigrants. Contrary to general understanding, non-visible immigrants (when considering factors such as skin color and clothing diverge the most from the pattern of the majority. Immigrants originating from European countries, such as Sweden and Poland, use the emergency room most frequently. From the qualitative aspects of the study, we have also found that primary health care services are not perceived as equitable.Conclusion: Recently arrived immigrants’ utilization of primary health care services shows an unfavorable pattern. The choice of primary health care service providers is dependent on the individual’s preferences, expectations, experiences and/or actual obstacles. The observed utilization of services provided at emergency rooms is one more reason for monitoring and increasing tolerance and cultural sensitivity in primary health care.

  7. Heat pumps in district heating networks

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    In the current Danish energy system, the majority of electricity and heat is produced in combined heat and power plants. With increasing shares of intermittent renewable power production, it becomes a challenging task to match power and heat production, as heat demand and production capacity...... constraints limit the power plants. Efficient heat pumps can be used to decouple the constraints of electricity and heat production, while maintaining the high energy efficiency needed to match the politically agreed carbon emission goals. The requirements in terms of COP, location, capacity and economy...... are calculated using an energy system model which includes power plants, heat pumps and district heating consumption profiles. The model is developed with focus on accurate representation of the performance of the units in different locations and operating modes. The model can assist in investment decisions...

  8. ICRF heating on helical devices

    International Nuclear Information System (INIS)

    Rasmussen, D.A.; Lyon, J.F.; Hoffman, D.J.; Murakami, M.; England, A.C.; Wilgen, J.B.

    1995-01-01

    Ion cyclotron range of frequency (ICRF) heating is currently in use on CHS and W7-AS and is a major element of the heating planned for steady state helical devices. In helical devices, the lack of a toroidal current eliminates both disruptions and the need for ICFR current drive, simplifying the design of antenna structures as compared to tokamak applications. However the survivability of plasma facing components and steady state cooling issues are directly applicable to tokamak devices. Results from LHD steady state experiments should be available on a time scale to strongly influence the next generation of steady state tokamak experiments. the helical plasma geometry provides challenges not faced with tokamak ICRF heating, including the potential for enhanced fast ion losses, impurity accumulation, limited access for antenna structures, and open magnetic field lines in the plasma edge. The present results and near term plans provide the basis for steady state ICRF heating of larger helical devices. An approach which includes direct electron, mode conversion, ion minority and ion Bernstein wave heating addresses these issues. 12 refs

  9. Multiperspective analysis of erosion tolerance

    Directory of Open Access Journals (Sweden)

    Sparovek Gerd

    2003-01-01

    Full Text Available Erosion tolerance is the most multidisciplinary field of soil erosion research. Scientists have shown lack in ability to adequately analyze the huge list of variables that influence soil loss tolerance definitions. For these the perspectives of erosion made by farmers, environmentalists, society and politicians have to be considered simultaneously. Partial and biased definitions of erosion tolerance may explain not only the polemic nature of the currently suggested values but also, in part, the nonadoption of the desired levels of erosion control. To move towards a solution, considerable changes would have to occur on how this topic is investigated, especially among scientists, who would have to change methods and strategies and extend the perspective of research out of the boundaries of the physical processes and the frontiers of the academy. A more effective integration and communication with the society and farmers, to learn about their perspective of erosion and a multidisciplinary approach, integrating soil, social, economic and environmental sciences are essential for improved erosion tolerance definitions. In the opinion of the authors, soil erosion research is not moving in this direction and a better understanding of erosion tolerance is not to be expected in the near future.

  10. Oscillating heat pipes

    CERN Document Server

    Ma, Hongbin

    2015-01-01

    This book presents the fundamental fluid flow and heat transfer principles occurring in oscillating heat pipes and also provides updated developments and recent innovations in research and applications of heat pipes. Starting with fundamental presentation of heat pipes, the focus is on oscillating motions and its heat transfer enhancement in a two-phase heat transfer system. The book covers thermodynamic analysis, interfacial phenomenon, thin film evaporation,  theoretical models of oscillating motion and heat transfer of single phase and two-phase flows, primary  factors affecting oscillating motions and heat transfer,  neutron imaging study of oscillating motions in an oscillating heat pipes, and nanofluid’s effect on the heat transfer performance in oscillating heat pipes.  The importance of thermally-excited oscillating motion combined with phase change heat transfer to a wide variety of applications is emphasized. This book is an essential resource and learning tool for senior undergraduate, gradua...

  11. Multidimensional Heat Conduction

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Analytical theory of multidimensional heat conduction. General heat conduction equation in three dimensions. Steay state, analytical solutions. The Laplace equation. Method of separation of variables. Principle of superposition. Shape factors. Transient, multidimensional heat conduction....

  12. Heat Roadmap Europe 1

    DEFF Research Database (Denmark)

    Connolly, David; Mathiesen, Brian Vad; Østergaard, Poul Alberg

    2012-01-01

    Heat Roadmap Europe (Pre-study 1) investigates the role of district heating in the EU27 energy system by mapping local conditions across Europe, identifying the potential for district heating expansion, and subsequently simulating the potential resource in an hourly model of the EU27 energy system....... In 2010, approximately 12% of the space heating demand in Europe is met by district heating, but in this study four alternative scenarios are considered for the EU27 energy system: 1. 2010 with 30% district heating 2. 2010 with 50% district heating 3. 2030 with 30% district heating 4. 2050 with 50......% district heating These scenarios are investigated in two steps. Firstly, district heating replaces individual boilers by converting condensing power plants to combined heat and power plants (CHP) to illustrate how district heating improves the overall efficiency of the energy system. In the second step...

  13. Heat Related Illnesses

    National Research Council Canada - National Science Library

    Carter, R; Cheuvront, S. N; Sawka, M. N

    2006-01-01

    .... The risk of serious heat illness can be markedly reduced by implementing a variety of countermeasures, including becoming acclimated to the heat, managing heat stress exposure, and maintaining hydration...

  14. Local address and emergency contact details

    CERN Multimedia

    2013-01-01

    The HR Department would like to remind members of the personnel that they are responsible for ensuring that their personal data concerning local address and preferred emergency contact details remains valid and up-to-date.   Both are easily accessible via the links below: Local address: https://edh.cern.ch/Document/Personnel/LocalAddressChange   Emergency contacts: https://edh.cern.ch/Document/Personnel/EC   Please take a few minutes to check your details and modify if necessary. Thank you in advance. HR Department Head Office

  15. Stress for Stress Tolerance? A Fundamentally New Approach in Mammalian Embryology

    DEFF Research Database (Denmark)

    Pribenszky, Csaba; Vajta, Gabor; Molnár, Miklós

    2010-01-01

    tolerance to various in vitro procedures. The aim of this review is to summarize reports on the effects of stress on gametes and embryos of several species. Treatment with sublethal doses of high hydrostatic pressure (HHP), osmotic, heat, or oxidative stress resulted in increased morphological survival...... activation, intracytoplasmic sperm injection and somatic cell nuclear transfer. Osmotic stress of oocytes resulted in higher developmental rates after cryopreservation, parthenogenetic activation and somatic cell nuclear transfer. Heat shock was reported to increase developmental competence...

  16. Contact Heat Exchanger

    Science.gov (United States)

    Fleming, M. L.; Stalmach, D. D.; Cox, R. L.

    1985-01-01

    Fluid pressure controls contact between heat pipe and heat exchanger. Heat exchanger system in cross section provides contact interface between fluid system and heat pipe with easy assembly/disassembly of heat-pipe/ pumped-liquid system. Originally developed for use in space, new device applicable on Earth where fluid system is linked with heat pipe, where rapid assembly/disassembly required, or where high pressures or corrosive fluids used.

  17. Seminar on heat pump research and applications: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Steele, R.V. Jr. (ed.)

    1984-11-01

    This volume is a compilation of papers prepared by speakers at a seminar on heat pumps. The seminar was organized by the Electric Power Research Institute (EPRI) in cooperation with Louisiana Power and Light Company and New Orleans Public Service, Inc. The seminar's purpose was to inform utility managers and engineers of the most recent developments in residential heat pump technology and applications. Statements by invited panelists on the outlook for heat pump technology are also included. The speakers, who represented key organizations in the heat pump area, including utilities, industry associations, manufacturers, independent research institutes, government, and EPRI, addressed the following topics: status of heat pump research and development, heat pump testing and rating; field monitoring of heat pumps; heat pump water heaters; heat pump reliability; and marketing programs for pumps. All papers, total of sixteen have been processed for inclusion in the Energy Data Base.

  18. B cells in operational tolerance.

    Science.gov (United States)

    Chesneau, M; Danger, R; Soulillou, J-P; Brouard, S

    2018-02-16

    Transplantation is currently the therapy of choice for endstage organ failure even though it requires long-term immunosuppresive therapy, with its numerous side effects, for acceptance of the transplanted organ. In rare cases however, patients develop operational tolerance, that is, graft survival without immunosuppression. Studies conducted on these patients reveal genetic, phenotypic, and functional signatures. They provide a better understanding of the immunological mechanisms involved in operational tolerance and define biomarkers that could be used to adapt immunosuppressive treatment to the individual, safely reduce immunosuppression doses, and ideally and safely guide immunosuppression withdrawal. This review summarizes studies that suggest a role for B cells as biomarkers of operational tolerance and discusses the use of B cells as a predictive tool for immunologic risk. Copyright © 2018. Published by Elsevier Inc.

  19. Network analysis of oyster transcriptome revealed a cascade of cellular responses during recovery after heat shock.

    Directory of Open Access Journals (Sweden)

    Lingling Zhang

    Full Text Available Oysters, as a major group of marine bivalves, can tolerate a wide range of natural and anthropogenic stressors including heat stress. Recent studies have shown that oysters pretreated with heat shock can result in induced heat tolerance. A systematic study of cellular recovery from heat shock may provide insights into the mechanism of acquired thermal tolerance. In this study, we performed the first network analysis of oyster transcriptome by reanalyzing microarray data from a previous study. Network analysis revealed a cascade of cellular responses during oyster recovery after heat shock and identified responsive gene modules and key genes. Our study demonstrates the power of network analysis in a non-model organism with poor gene annotations, which can lead to new discoveries that go beyond the focus on individual genes.

  20. VT E911 ESITE geocoder - address points

    Data.gov (United States)

    Vermont Center for Geographic Information — VT E911 ESITE geocoder - address points. VCGI, in collaboration with the VT E911 Board, has created a suite of geocoding services that can be used to batch geocode...

  1. What is Fault Tolerant Control

    DEFF Research Database (Denmark)

    Blanke, Mogens; Frei, C. W.; Kraus, K.

    2000-01-01

    Faults in automated processes will often cause undesired reactions and shut-down of a controlled plant, and the consequences could be damage to the plant, to personnel or the environment. Fault-tolerant control is the synonym for a set of recent techniques that were developed to increase plant...... availability and reduce the risk of safety hazards. Its aim is to prevent that simple faults develop into serious failure. Fault-tolerant control merges several disciplines to achieve this goal, including on-line fault diagnosis, automatic condition assessment and calculation of remedial actions when a fault...

  2. Damage Tolerance Assessment of Friction Pull Plug Welds in an Aluminum Alloy

    Science.gov (United States)

    McGill, Preston; Burkholder, Jonathan

    2012-01-01

    Friction stir welding is a solid state welding process used in the fabrication of cryogenic propellant tanks. Self-reacting friction stir welding is one variation of the friction stir weld process being developed for manufacturing tanks. Friction pull plug welding is used to seal the exit hole that remains in a circumferential self-reacting friction stir weld. A friction plug weld placed in a self-reacting friction stir weld results in a non-homogenous weld joint where the initial weld, plug weld, their respective heat affected zones and the base metal all interact. The welded joint is a composite plastically deformed material system with a complex residual stress field. In order to address damage tolerance concerns associated with friction plug welds in safety critical structures, such as propellant tanks, nondestructive inspection and proof testing may be required to screen hardware for mission critical defects. The efficacy of the nondestructive evaluation or the proof test is based on an assessment of the critical flaw size. Test data relating residual strength capability to flaw size in an aluminum alloy friction plug weld will be presented.

  3. Tolerating extremism : to what extent should intolerance be tolerated?

    NARCIS (Netherlands)

    Guiora, Amos Neuser

    2013-01-01

    In discussing extremism, the key questions are: to whom is a duty owed and what are the limits of intolerance that are to be tolerated? Answering these questions requires examining limits and rights; analyzing them in the context of extremism is the ‘core’ of this book. While freedom of speech and

  4. Development and implementation of setpoint tolerances for special safety systems

    International Nuclear Information System (INIS)

    Oliva, A.F.; Balog, G.; Parkinson, D.G.; Archinoff, G.H.

    1991-01-01

    The establishment of tolerances and impairment limits for special safety system setpoints is part of the process whereby the plant operator demonstrates to the regulatory authority that the plant operates safely and within the defined plant licensing envelope. The licensing envelope represents the set of limits and plant operating state and for which acceptably safe plant operation has been demonstrated by the safety analysis. By definition, operation beyond this envelope contributes to overall safety system unavailability. Definition of the licensing envelope is provided in a wide range of documents including the plant operating licence, the safety report, and the plant operating policies and principles documents. As part of the safety analysis, limits are derived for each special safety system initiating parameter such that the relevant safety design objectives are achieved for all design basis events. If initiation on a given parameter occurs at a level beyond its limit, there is a potential reduction in safety system effectiveness relative to the performance credited in the plant safety analysis. These safety system parameter limits, when corrected for random and systematic instrument errors and other errors inherent in the process of periodic testing or calibration, are then used to derive parameter impairment levels and setpoint tolerances. This paper describes the methodology that has evolved at Ontario Hydro for developing and implementing tolerances for special safety system parameters (i.e., the shutdown systems, emergency coolant injection system and containment system). Tolerances for special safety system initiation setpoints are addressed specifically, although many of the considerations discussed here will apply to performance limits for other safety system components. The first part of the paper deals with the approach that has been adopted for defining and establishing setpoint limits and tolerances. The remainder of the paper addresses operational

  5. South African address standard and initiatives towards an international address standard

    CSIR Research Space (South Africa)

    Cooper, Antony K

    2008-10-01

    Full Text Available Various countries and international organizations have address standards or are developing them. An address is needed for many more applications than just postal delivery, such as: goods delivery; connecting utilities; opening bank accounts; voting...

  6. South African address standard and initiatives towards an international address standard.

    CSIR Research Space (South Africa)

    Cooper, Anthony K

    2008-09-01

    Full Text Available Various countries and international organizations have address standards or are developing them. An address is needed for many more applications than just postal delivery, such as: goods delivery; connecting utilities; opening bank accounts; voting...

  7. Keynote Address: Outstanding Problems in Solar Physics

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The solar neutrino problem; Structure of the solar interior (helioseismology); The solar magnetic field (dynamo, solar cycle, corona); Hydrodynamics of coronal loops; MHD oscillations and waves (coronal seismology); The coronal heating problem; Self-organized criticality (from nanoflares to giant flares) ...

  8. Heat Roadmap Europe

    DEFF Research Database (Denmark)

    Hansen, Kenneth; Connolly, David; Lund, Henrik

    2015-01-01

    The cost of heat savings in buildings increase as more heat savings are achieved due to the state of the building stock and hence, alternatives other than savings typically become more economically feasible at a certain level of heat reductions. It is important to identify when the cost of heat...... savings become more expensive than the cost of sustainable heat supply, so society does not overinvest in heat saving measures. This study first investigates the heat saving potentials for different countries in Europe, along with their associated costs, followed by a comparison with alternative ways...... of supplying sustainable heating. Different heat production options are included in terms of individual and community heating systems. Furthermore, the levelised cost of supplying sustainable heat is estimated for both a single technology and from an energy system perspective. The results are analysed...

  9. Aerobic influence on neuromuscular function and tolerance during passive hyperthermia.

    Science.gov (United States)

    Morrison, Shawnda A; Sleivert, Gordon G; Cheung, Stephen

    2006-10-01

    To determine the role of aerobic fitness on central neuromuscular activation and maximal voluntary contractile force during hyperthermia. Thirty-seven healthy males in three distinct groups based on aerobic fitness and training history were passively heated using a liquid conditioning garment in a hot (35 degrees C, 50% RH) environment with the intention of testing neuromuscular function with whole-body hyperthermia. Of these initial participants, 11 of the 13 highly fit (HF; VO2max = 71.2 +/- 5.9 mL x kg(-1) x min(-1), body fat = 5.6 +/- 1.9%), 11 of the 13 moderately fit (MF; 57.2 +/- 4.2 mL x kg(-1) x min(-1), 11 +/- 3.4%), and 4 of the 11 lower-fit (LF; 49.6 +/- 1.1 mL x kg(-1) x min(-1), 19.4 +/- 2.6%) individuals tolerated heating to 39.0 degrees C, with the remainder terminating the experimental protocol early. Maximal force output and voluntary activation were examined during a 10-s maximal isometric knee extension. Passive heating attenuated force production (-61.7 +/- 69.6 N change from initial values) and decreased voluntary activation (8.6 (12.6), 18.1 (12.4), and 6.1 (3.1)% for HF, MF, and LF training groups, respectively). Cardiovascular strain moderately increased to 60 +/- 14% (P heating (98 +/- 15, 99 +/- 7, and 79 +/- 5 mm Hg for HF, MF, and LF, respectively; P heating to 39.0 degrees C (and above) differed between the HF and MF compared with LF, despite no difference in their psychophysical rankings of thermal sensations and/or (dis)comfort. Low aerobic fitness and activity level are associated with a decreased tolerance to passive hyperthermia. However, at high body temperatures, maximum force production and voluntary activation were impaired to an equal level regardless of training status.

  10. Tunneling of heat: Beyond linear response regime

    Science.gov (United States)

    Walczak, Kamil; Saroka, David

    2018-02-01

    We examine nanoscale processes of heat (energy) transfer as carried by electrons tunneling via potential barriers and molecular interconnects between two heat reservoirs (thermal baths). For that purpose, we use Landauer-type formulas to calculate thermal conductance and quadratic correction to heat flux flowing via quantum systems. As an input, we implement analytical expressions for transmission functions related to simple potential barriers and atomic bridges. Our results are discussed with respect to energy of tunneling electrons, temperature, the presence of resonant states, and specific parameters characterizing potential barriers as well as heat carriers. The simplicity of semi-analytical models developed by us allows to fit experimental data and extract crucial information about the values of model parameters. Further investigations are expected for more realistic transmission functions, while time-dependent aspects of nanoscale heat transfer may be addressed by using the concept of wave packets scattered on potential barriers and point-like defects within regular (periodic) nanostructures.

  11. Review of progress on enhanced accident tolerant fuel

    International Nuclear Information System (INIS)

    McCoy, K.; Dunn, B.; Kochendarfer, R.

    2015-01-01

    The accident at Fukushima has resulted in renewed interest in understanding the performance of nuclear power plants under accident conditions. Part of that interest is directed toward determining how to improve the performance of fuel during an accident that involves long exposures of the fuel to high temperatures. This paper describes the method being used by AREVA to select and evaluate approaches for improving the accident tolerance of nuclear fuel. The method involves starting with a large number of approaches that might enhance accident tolerance, and reviewing how well each approach satisfies a set of engineering requirements and goals. Among the approaches investigated we have the development of fuel pellets that contain a second phase to improve thermal conductivity, the use of molybdenum alloy tubing as fuel cladding, the use of oxidation-resistant coatings to zirconium cladding, and the use of nanoparticles in the coolant to improve heat transfer

  12. Enter your email-address: how German internet users manage their email addresses

    NARCIS (Netherlands)

    Utz, S.

    2004-01-01

    Writing E-mail is the most popular Internet activity. Meanwhile, many people have more than one E-mail address. The question how people manage their E-mail addresses, more specifically, whether they use them deliberately for different purposes, is the central question of this paper. E-mail addresses

  13. 46 CFR 67.113 - Managing owner designation; address; requirement to report change of address.

    Science.gov (United States)

    2010-10-01

    ... change of address. The owner of each vessel must designate a managing owner on the Application for...) Whenever the address of the managing owner changes, the managing owner shall notify the Director, National... 46 Shipping 2 2010-10-01 2010-10-01 false Managing owner designation; address; requirement to...

  14. Climatic consequences of adopting drought tolerant vegetation over Los Angeles as a response to California drought

    Science.gov (United States)

    Ban-Weiss, G. A.; Vahmani, P.

    2016-12-01

    During 2012-2014, drought in California resulted in policies to reduce water consumption. One measure pursued was replacing lawns with landscapes that minimize water consumption, such as drought tolerant vegetation. If implemented at broad scale, this strategy would result in reductions in irrigation, and changes in land surface characteristics. In this study, we employ a modified regional climate model to assess the climatic consequences of adopting drought tolerant vegetation over the Los Angeles metropolitan area. Transforming lawns to drought tolerant vegetation resulted in daytime warming of up to 1.9°C, largely due to decreases in irrigation that shifted surface energy partitioning toward higher sensible and lower latent heat flux. During nighttime, however, adopting drought tolerant vegetation caused mean cooling of about 3°C, due to changes in soil thermodynamic properties and heat exchange dynamics between the surface and ground. Our results show that nocturnal cooling effects, which are larger in magnitude and of great importance for public health during heat events, could counterbalance the daytime warming attributed to the studied water conservation strategy. A more aggressive implementation, assuming all urban vegetation was replaced with drought tolerant vegetation, resulted in an average daytime cooling of 0.2°C, largely due to weakened sea-breeze patterns, highlighting the important role of land surface roughness in this coastal megacity.

  15. Selection of high temperature and salinity tolerant Trichoderma isolates with antagonistic activity against Sclerotium rolfsii.

    Science.gov (United States)

    Poosapati, Sowmya; Ravulapalli, Prasad Durga; Tippirishetty, Navaneetha; Vishwanathaswamy, Dinesh Kumar; Chunduri, Sarada

    2014-01-01

    Trichoderma isolates were collected from varied agro-climatic zones of India and screened for high temperature and salinity tolerance. Among all the isolates tested, T. asperellum, TaDOR673 was highly tolerant to heat shock of 52°C with a mean spore count (log c.f.u/ml) of 4.33. The isolate after recovery from heat shock possessed higher germination rate and biomass production compared to its wild counterpart, upon prolonged exposure to 37°C. Under stress, TaDOR673 accumulated >15% of trehalose and >5% of mannose and raffinose compared to the wild type strain signifying their role in stress tolerance. T. asperellum, TaDOR693 and T. asperellum, TaDORS3 were identified as superior salt-tolerant isolates. Interestingly, TaDOR673 also possessed similar tolerance levels to increasing saline concentrations as indicated by its improved colony growth under stress conditions. T. asperellum, TaDOR673 and T. asperellum, TaDOR7316 effectively controlled the collar rot disease in groundnut by 79.7% when screened in vitro and in vivo. Thus, the study identified a potential thermotolerant and saline tolerant strain of Trichoderma, TaDOR673 that could be used as potential bioagent in stressed soils.

  16. When Should Sects be Tolerated?

    DEFF Research Database (Denmark)

    Hvithamar, Annika

    2009-01-01

    Jehovas vidners kontroverser med majoritetssamfundet gør dem til et godt test-case for tolerance. I artiklen bruges udviklingen af bevægelsens syn på blodstransfusioner til at diskutere, hvordan institutionaliseringen af en minoritetsbevægelse får kontroversernes styrke til at mindskes, men også ...

  17. Stepping Back from Zero Tolerance

    Science.gov (United States)

    Browne-Dianis, Judith

    2011-01-01

    Schools' use of zero tolerance policies has been increasing since the 1980s as part of a societal movement to crack down on drug abuse and violence among youth. But far from making schools safer, this harsh, inflexible approach to discipline has been eroding the culture of schools and creating devastating consequences for children, writes…

  18. Effects of Drought, Heat and Their Interaction on the Growth, Yield and Photosynthetic Function of Lentil (Lens culinaris Medikus) Genotypes Varying in Heat and Drought Sensitivity

    Science.gov (United States)

    Sehgal, Akanksha; Sita, Kumari; Kumar, Jitendra; Kumar, Shiv; Singh, Sarvjeet; Siddique, Kadambot H. M.; Nayyar, Harsh

    2017-01-01

    Rising temperatures and drought stress limit the growth and production potential of lentil (Lens culinaris Medikus), particularly during reproductive growth and seed filling. The present study aimed to (i) investigate the individual and combined effects of heat and drought stress during seed filling, (ii) determine the response of lentil genotypes with contrasting heat and drought sensitivity, and (iii) assess any cross tolerance in contrasting genotypes. For this purpose, eight lentil genotypes (two drought-tolerant, two drought-sensitive, two heat-tolerant, two heat-sensitive) were either sown at the normal time (second week of November 2014), when the temperatures at the time of seed filling were below 30/20°C (day/night), or sown late (second week of February 2015) to impose heat stress (temperatures > 30/20°C (day/night) during reproducive growth and seed filling. Half of the pots in each sowing environment were fully watered throughout (100% field capacity) while the others had water withheld (50% of field capacity) from the start of seed filling to maturity. Both heat and drought, individually or in combination, damaged cell membranes, photosynthetic traits and water relations; the effects were more severe with the combined stress. RuBisCo and stomatal conductance increased with heat stress but decreased with drought and the combined stress. Leaf and seed sucrose decreased with each stress in conjunction with its biosynthetic enzyme, while its (sucrose) hydrolysis increased under heat and drought stress, but was inhibited due to combination of stresses. Starch increased under heat stress in leaves but decreased in seeds, but drastically declined in seeds under drought alone or in combination with heat stress. At the same time, starch hydrolysis in leaves and seeds increased resulting in an accumulation of reducing sugars. Heat stress inhibited yield traits (seed number and seed weight per plant) more than drought stress, while drought stress reduced

  19. A non-equilibrium model for soil heating and moisture transport during extreme surface heating: The soil (heat-moisture-vapor) HMV-Model Version

    Science.gov (United States)

    William Massman

    2015-01-01

    Increased use of prescribed fire by land managers and the increasing likelihood of wildfires due to climate change require an improved modeling capability of extreme heating of soils during fires. This issue is addressed here by developing and testing the soil (heat-moisture-vapor) HMVmodel, a 1-D (one-dimensional) non-equilibrium (liquid- vapor phase change)...

  20. District Heating Systems Performance Analyses. Heat Energy Tariff

    Science.gov (United States)

    Ziemele, Jelena; Vigants, Girts; Vitolins, Valdis; Blumberga, Dagnija; Veidenbergs, Ivars

    2014-12-01

    The paper addresses an important element of the European energy sector: the evaluation of district heating (DH) system operations from the standpoint of increasing energy efficiency and increasing the use of renewable energy resources. This has been done by developing a new methodology for the evaluation of the heat tariff. The paper presents an algorithm of this methodology, which includes not only a data base and calculation equation systems, but also an integrated multi-criteria analysis module using MADM/MCDM (Multi-Attribute Decision Making / Multi-Criteria Decision Making) based on TOPSIS (Technique for Order Performance by Similarity to Ideal Solution). The results of the multi-criteria analysis are used to set the tariff benchmarks. The evaluation methodology has been tested for Latvian heat tariffs, and the obtained results show that only half of heating companies reach a benchmark value equal to 0.5 for the efficiency closeness to the ideal solution indicator. This means that the proposed evaluation methodology would not only allow companies to determine how they perform with regard to the proposed benchmark, but also to identify their need to restructure so that they may reach the level of a low-carbon business.

  1. Use of feedback control to address flight safety issues

    Science.gov (United States)

    Ganguli, Subhabrata

    This thesis addresses three control problems related to flight safety. The first problem relates to the scope of improvement in performance of conventional flight control laws. In particular, aircraft longitudinal axis control based on the Total Energy Control System (TECS) is studied. The research draws attention to a potentially sluggish and undesirable aircraft response when the engine dynamics is slow (typically the case). The proposed design method uses a theoretically well-developed modern design method based on Hinfinity optimization to improve the aircraft dynamic behavior in spite of slow engine characteristics. At the same time, the proposed design method achieves other desirable performance goals such as insensitivity to sensor noise and wind gust rejection: all addressed in one unified framework. The second problem is based on a system level analysis of control structure hierarchy for aircraft flight control. The objective of the analysis problem is to translate outer-loop stability and performance specifications into a comprehensive inner-loop metric. The prime motivation is to make the flight control design process more systematic and the system-integration reliable and independent of design methodology. The analysis problem is posed within the robust control analysis framework. Structured singular value techniques and free controller parameterization ideas are used to impose a hierarchical structure for flight control architecture. The third problem involves development and demonstration of a new reconfiguration strategy in the flight control architecture that has the potential of improving flight safety while keeping cost and complexity low. This research proposes a fault tolerant feature based on active robust reconfiguration. The fault tolerant control problem is formulated in the Linear Parameter Varying (LPV) design framework. A prime advantage of this approach is that the synthesis results in a single nonlinear controller (as opposed to a bank

  2. Expression of a monothiol glutaredoxin, AtGRXS17, in tomato (Solanum lycopersicum) enhances drought tolerance

    Science.gov (United States)

    Abiotic stresses are a major factor limiting crop growth and productivity. Our previous studies revealed that Arabidopsis thaliana glutaredoxin S17 (AtGRXS17) has conserved functions in plant tolerance to heat and chilling stress in tomato. Here, we report that ectopic expression of AtGRXS17 in toma...

  3. Chronic stress moderates the impact of social exclusion on pain tolerance: an experimental investigation.

    Science.gov (United States)

    Pieritz, Karoline; Schäfer, Sarina J; Strahler, Jana; Rief, Winfried; Euteneuer, Frank

    2017-01-01

    Experiences of social pain due to social exclusion may be processed in similar neural systems that process experiences of physical pain. The present study aimed to extend the findings on social exclusion and pain by examining the impact of social exclusion on an affective (ie, heat pain tolerance) and a sensory component of pain (ie, heat pain intensity). Whether a potential effect may be moderated by chronic life stress, social status, or social sup-port was further examined. A community-based sample of 59 women was studied. Social exclusion and inclusion were experimentally manipulated by using a virtual ball-tossing game called Cyberball in which participants were randomly assigned to either being excluded or being included by two other virtual players. Heat pain tolerance and intensity were assessed before and after the game. Potential psychosocial moderators were assessed via a questionnaire. The main finding of this study is that chronic stress moderates the impact of social exclusion on pain tolerance ( p socially excluded participants showed a lower heat pain tolerance than participants who were socially included. Contrary to the authors' hypothesis, pain sensitivity was increased in socially included participants compared with socially excluded participants after the game ( p social exclusion.

  4. Discrepancy between stimulus response and tolerance of pain in Alzheimer disease

    DEFF Research Database (Denmark)

    Jensen-Dahm, Christina; Werner, Mads U; Jensen, Troels Staehelin

    2015-01-01

    BACKGROUND: Affective-motivational and sensory-discriminative aspects of pain were investigated in patients with mild to moderate Alzheimer disease (AD) and healthy elderly controls using the cold pressor test tolerance and repetitive stimuli of warmth and heat stimuli, evaluating the stimulus...

  5. Solar Heating Equipment

    Science.gov (United States)

    1981-01-01

    Solar Unlimited, Inc.'s suncatcher line includes a variety of solar arrays, derived from NASA's satellite program: water heating only, partial home heating, or water and whole house central heating. Solar Unlimited developed a set of vigorous requirements to avoid problems common to solar heating technologies.

  6. Nature's Heat Exchangers.

    Science.gov (United States)

    Barnes, George

    1991-01-01

    Discusses the heat-transfer systems of different animals. Systems include heat conduction into the ground, heat transferred by convection, heat exchange in lizards, fish and polar animals, the carotid rete system, electromagnetic radiation from animals and people, and plant and animal fiber optics. (MDH)

  7. Transient Heat Conduction

    DEFF Research Database (Denmark)

    Rode, Carsten

    1998-01-01

    Analytical theory of transient heat conduction.Fourier's law. General heat conducation equation. Thermal diffusivity. Biot and Fourier numbers. Lumped analysis and time constant. Semi-infinite body: fixed surface temperature, convective heat transfer at the surface, or constant surface heat flux...

  8. Direct fired heat exchanger

    Science.gov (United States)

    Reimann, Robert C.; Root, Richard A.

    1986-01-01

    A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

  9. Centrally managed unified shared virtual address space

    Energy Technology Data Exchange (ETDEWEB)

    Wilkes, John

    2018-02-13

    Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontend interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.

  10. Centrally managed unified shared virtual address space

    Science.gov (United States)

    Wilkes, John

    2018-02-13

    Systems, apparatuses, and methods for managing a unified shared virtual address space. A host may execute system software and manage a plurality of nodes coupled to the host. The host may send work tasks to the nodes, and for each node, the host may externally manage the node's view of the system's virtual address space. Each node may have a central processing unit (CPU) style memory management unit (MMU) with an internal translation lookaside buffer (TLB). In one embodiment, the host may be coupled to a given node via an input/output memory management unit (IOMMU) interface, where the IOMMU frontend interface shares the TLB with the given node's MMU. In another embodiment, the host may control the given node's view of virtual address space via memory-mapped control registers.

  11. Heat Acclimation and Water-Immersion Deconditioning: Responses to Exercise

    Science.gov (United States)

    Shvartz, E.; Bhattacharya, A.; Sperinde, S. J.; Brock, P. J.; Sciaraffa, D.; Haines, R. F.; Greenleaf, J. E.

    1977-01-01

    Simulated subgravity conditions, such as bed rest and water immersion, cause a decrease in a acceleration tolerance (3, 4), tilt tolerance (3, 9, 10), work capacity (5, 7), and plasma volume (1, 8-10). Moderate exercise training performed during bed rest (4) and prior to water immersion (5) provides some protection against the adverse effects of deconditioning, but the relationship between exercise and changes due to deconditioning remains unclear. Heat acclimation increases plasma and interstitial volumes, total body water, stroke volume (11), and tilt tolerance (6) and may, therefore, be a more efficient method of ameliorating deconditioning than physical training alone. The present study was undertaken to determine the effects of heat acclimation and moderate physical training, performed in cool conditions, on water-immersion deconditioning.

  12. District heating in Switzerland

    International Nuclear Information System (INIS)

    Herzog, F.

    1991-01-01

    District heating has been used in Switzerland for more than 50 years. Its share of the heat market is less than 3% today. An analysis of the use of district heating in various European countries shows that a high share of district heating in the heat market is always dependent on ideal conditions for its use. Market prospects and possible future developments in the use of district heating in Switzerland are described in this paper. The main Swiss producers and distributors of district heating are members of the Association of District Heating Producers and Distributors. This association supports the installation of district heating facilities where ecological, energetical and economic aspects indicate that district heating would be a good solution. (author) 2 tabs., 6 refs

  13. Content addressable memories in scientific instruments

    International Nuclear Information System (INIS)

    Lotto, I. de; Golinelli, S.

    1975-01-01

    The content-addressable-memory feature of a new system designed in these laboratories for non-destructive testing of nuclear reactor pressure vessels based on acoustic emission analysis is presented. The content addressable memory is divided into two parts: the first selects the most frequent events among incoming ones (FES: Frequent Event Selection memory), the second stores the frequent events singled out (FEM: Frequent Event Memory). The statistical behaviour of FES is analyzed, and experimental results are compared with theoretical ones; the model presented proved to be a useful tool in dimensioning the instrument store capacity. (Auth.)

  14. Initiative Addresses Subsurface Energy and Environment Problems

    Science.gov (United States)

    Bodvarsson, Gudmundur S.; Majer, Ernest L.; Wang, Joseph S. Y.; Colwell, Frederick; Redden, George

    2006-01-01

    Members of the geoscience community are cooperating in conceptualizing fundamental, crosscutting research to address major obstacles to solving energy and environmental problems related to the subsurface, through the SECUREarth initiative, which began in 2004. Addressing problems, such as reliable nuclear waste storage and safe carbon dioxide (CO2) sequestration, are critical to maintaining an economical and safe energy supply and clean environment. A recent workshop in Golden, Colo., helped to further the development of the SECUREarth (Scientific Energy/Environmental Crosscutting Underground Research for Urgent Solutions to Secure the Earth's Future) initiative by identifying the key scientific challenges in the geosciences, as well as to target possible approaches for overcoming roadblocks.

  15. Welfare work addressing immigrants and refugees

    DEFF Research Database (Denmark)

    Øland, Trine

    In this presentation I will discuss the ways in which welfare workers addressing immigrants and refugees (re)produce integrationist visions, symbolizing society as an integrated whole and immigrants/refugees as a distraction to that whole. Paradoxically, welfare workers also oppose...... these integrationist visions in their quest to protect immigrants’ and refugees’ fundamental wellbeing and status as human beings with equal rights, group life and history. These opposing elements generate ambiguity and contradiction within integrationist welfare work. The ambition of the presentation is to enquire......, nurses and more) addressing immigrants and refugees and their families and descendants in the Danish welfare nation-state....

  16. Addressing techniques of liquid crystal displays

    CERN Document Server

    Ruckmongathan, Temkar N

    2014-01-01

    Unique reference source that can be used from the beginning to end of a design project to aid choosing an appropriate LCD addressing technique for a given application This book will be aimed at design engineers who are likely to embed LCD drivers and controllers in many systems including systems on chip. Such designers face the challenge of making the right choice of an addressing technique that will serve them with best performance at minimal cost and complexity. Readers will be able to learn about various methods available for driving matrix LCDs and the comparisons at the end of each chap

  17. Shared address collectives using counter mechanisms

    Science.gov (United States)

    Blocksome, Michael; Dozsa, Gabor; Gooding, Thomas M; Heidelberger, Philip; Kumar, Sameer; Mamidala, Amith R; Miller, Douglas

    2014-02-18

    A shared address space on a compute node stores data received from a network and data to transmit to the network. The shared address space includes an application buffer that can be directly operated upon by a plurality of processes, for instance, running on different cores on the compute node. A shared counter is used for one or more of signaling arrival of the data across the plurality of processes running on the compute node, signaling completion of an operation performed by one or more of the plurality of processes, obtaining reservation slots by one or more of the plurality of processes, or combinations thereof.

  18. Introduction to heat transfer

    CERN Document Server

    SUNDÉN, B

    2012-01-01

    Presenting the basic mechanisms for transfer of heat, Introduction to Heat Transfer gives a deeper and more comprehensive view than existing titles on the subject. Derivation and presentation of analytical and empirical methods are provided for calculation of heat transfer rates and temperature fields as well as pressure drop. The book covers thermal conduction, forced and natural laminar and turbulent convective heat transfer, thermal radiation including participating media, condensation, evaporation and heat exchangers.

  19. Heat Roadmap Europe 2

    DEFF Research Database (Denmark)

    Connolly, David; Mathiesen, Brian Vad; Østergaard, Poul Alberg

    are identified and then, the EU27 energy system is modelled to investigate the impact of district heating. The results indicate that a combination of heat savings, district heating in urban areas, and individual heat pumps in rural areas will enable the EU27 to reach its greenhouse gas emission targets by 2050......, but at a cheaper price than a scenario which focuses primarily on the implementation of heat savings....

  20. Hyperspectral imaging to identify salt-tolerant wheat lines

    Science.gov (United States)

    Moghimi, Ali; Yang, Ce; Miller, Marisa E.; Kianian, Shahryar; Marchetto, Peter

    2017-05-01

    In order to address the worldwide growing demand for food, agriculture is facing certain challenges and limitations. One of the important threats limiting crop productivity is salinity. Identifying salt tolerate varieties is crucial to mitigate the negative effects of this abiotic stress in agricultural production systems. Traditional measurement methods of this stress, such as biomass retention, are labor intensive, environmentally influenced, and often poorly correlated to salinity stress alone. In this study, hyperspectral imaging, as a non-destructive and rapid method, was utilized to expedite the process of identifying relatively the most salt tolerant line among four wheat lines including Triticum aestivum var. Kharchia, T. aestivum var. Chinese Spring, (Ae. columnaris) T. aestivum var. Chinese Spring, and (Ae. speltoides) T. aestivum var. Chinese Spring. To examine the possibility of early detection of a salt tolerant line, image acquisition was started one day after stress induction and continued on three, seven, and 12 days after adding salt. Simplex volume maximization (SiVM) method was deployed to detect superior wheat lines in response to salt stress. The results of analyzing images taken as soon as one day after salt induction revealed that Kharchia and (columnaris)Chinese Spring are the most tolerant wheat lines, while (speltoides) Chinese Spring was a moderately susceptible, and Chinese Spring was a relatively susceptible line to salt stress. These results were confirmed with the measuring biomass performed several weeks later.