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Sample records for water physiological characteristics

  1. [Photosynthetic and water physiological characteristics of weedy rice in northern China].

    PubMed

    Gao, Qi; Ma, Dian-Rong; Kong, De-Xiu; Wang, Wen-Jia; Tong, Hui; Zhao, Ming-Hui; Xu, Zheng-Jin; Chen, Wen-Fu

    2013-11-01

    Weedy rice is an important germplasm source of rice, which has the characteristics of cold-, drought-, and barren tolerance. Taking 88 accessions of weedy rice and 4 varieties of cultivated rice in northern China as test materials, this paper studied the photosynthetic characteristics (photosynthetic rate, transpiration rate, and stomatal conductance), water physiological characteristics, and their interrelationships of weedy rice in northern China. There existed greater differences in the photosynthetic and water physiological characteristics among the weedy rice accessions, possessing abundant diversity. The photosynthetic rate of the accessions was from 12.47 micromol CO2 x m(-2) x s(-1) to 28.67 micromol CO2 X m(-2) x s(-1), and the instantaneous water use efficiency was from 1.39 mg x g(-1) to 3.40 mg x g(-1). Among the photosynthetic parameters, intercellular CO2 concentration had the smallest variable coefficient, while stomatal conductance had the largest one. The photosynthetic rate had significant conic relationships with transpiration rate and stomatal conductance, and had a linear relationship with intercellular CO2 concentration. The significant conic relationships also existed between the instantaneous water use efficiency and the transpiration rate and stomatal conductance. The excellent features of weedy rice could be used to improve the cultivated rice varieties.

  2. [Effects of simulated acid rain on water physiological characteristics of Myrica rubra seedlings].

    PubMed

    Yaho, Zhao-bin; Jiang, Hong; Yu, Shu-quan; Lu, Mei-juan

    2011-08-01

    Taking the seedlings of typical subtropical economic tree species Myrica rubra in Zhejiang Province as test materials, a pot experiment was conducted to study their water physiological characteristics under effects of simulated acid rain (pH 2.5 and pH 4.0), with water (pH 5.6) as the control. Season, year, and acid rain all had significant effects on the photosynthetic rate (Pn). Among the treatments, the Pn had a greater difference in summer than in spring and autumn, and was higher in treatment acid rain (pH 4.0). Season, year, acid rain, and the interactions of season and year and of the three factors had significant effects on the stomata conductance (Gs), and also, the Gs had a greater difference among the treatments in summer than in spring and autumn. Acid rain had inhibitory effect on Gs. Season, year, acid rain, and the interactions of season and year and of season and acid rain affected the transpiration rate (Tr) significantly. Same as Pn and Gs, the Tr had a greater difference among the treatments in summer than in spring and autumn. Acid rain (pH 2.5) had the strongest inhibitory effect on Tr. Acid rain and the interactions of season and year and of season and acid rain had significant effects on the water use efficiency (WUE), and acid rain (pH 2.5) had definitely positive effect on the WUE.

  3. [Water physiological characteristics and leaf traits of different aged Salix cheilophila on alpine sandy land].

    PubMed

    Liu, Hai-Tao; Jia, Zhi-Qing; Zhu, Ya-Juan; Yu, Yang; Li, Qing-Xue

    2012-09-01

    Taking 4-, 11-, 25-, and 37- year old Salix cheilophila stands on the alpine sandy land of Gonghe basin in Qinghai of West China as test objects, a laboratory test was conducted on their relative water deficit, water holding ability, specific leaf area (SLA), leaf mass-based nitrogen concentration (N(mass)) and phosphorous concentration (P(mass)), and N(mass)/P(mass), aimed to understand the variation patterns of the water physiological characteristics and leaf traits of different aged S. cheilophila on alpine sandy land. No significant difference was observed in the relative water deficit of the four stands. The daily mean value of water potential of the 37-year old stand was significantly lower, as compared with that of the other three stands, and the 4- and 11-year old stands had a significantly lower daily mean water potential than the 25-year old stand. The water loss rate of the 4-year old stand was significantly lower than that of the other three stands, and the 25-year old S. cheilophila stand had a significantly lower water loss rate than the 11-year old stand. The 4-year old stand also had a significantly lower SLA than the other three stands, implying its higher water use efficiency. The N(mass) of the 11-year old stand was significantly higher than that of the other three stands, and the 25-year old stand had a significantly higher N(mass) than the 37-year old stand, implying that the 11- and 25-year old stands had a higher photosynthetic capacity. The P(mass) of the 11-year old stand was significantly higher than that of the 25- and 37-year old stands, and the 4-year old stand had a significantly higher P(mass) than the 25-year old stand. The N(mass)/P(mass) of the four stands was 5.16-6.28, and the 25-year old stand had a significantly higher N(mass)/P(mass) than the 4- and 11-year old stands. The N(mass) of the four stands was significantly positively correlated with P(mass) the P(mass) was highly significantly negatively correlated with N

  4. Water Characteristics.

    ERIC Educational Resources Information Center

    Reed, Gregory D.

    1978-01-01

    Presents a literature review of the nature and analysis of chemical species in water, covering publications of 1967-77. This review is concerned with water characteristics. A list of 49 references is also presented. (HM)

  5. Physiological water model development

    NASA Technical Reports Server (NTRS)

    Doty, Susan

    1993-01-01

    The water of the human body can be categorized as existing in two main compartments: intracellular water and extracellular water. The intracellular water consists of all the water within the cells and constitutes over half of the total body water. Since red blood cells are surrounded by plasma, and all other cells are surrounded by interstitial fluid, the intracellular compartment has been subdivided to represent these two cell types. The extracellular water, which includes all of the fluid outside of the cells, can be further subdivided into compartments which represent the interstitial fluid, circulating blood plasma, lymph, and transcellular water. The interstitial fluid surrounds cells outside of the vascular system whereas plasma is contained within the blood vessels. Avascular tissues such as dense connective tissue and cartilage contain interstitial water which slowly equilibrates with tracers used to determine extracellular fluid volume. For this reason, additional compartments are sometimes used to represent these avascular tissues. The average size of each compartment, in terms of percent body weight, has been determined for adult males and females. These compartments and the forces which cause flow between them are presented. The kidneys, a main compartment, receive about 25 percent of the cardiac output and filters out a fluid similar to plasma. The composition of this filtered fluid changes as it flows through the kidney tubules since compounds are continually being secreted and reabsorbed. Through this mechanism, the kidneys eliminate wastes while conserving body water, electrolytes, and metabolites. Since sodium accounts for over 90 percent of the cations in the extracellular fluid, and the number of cations is balanced by the number of anions, considering the renal handling sodium and water only should sufficiently describe the relationship between the plasma compartment and kidneys. A kidney function model is presented which has been adapted from a

  6. Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters

    NASA Astrophysics Data System (ADS)

    Trimborn, Scarlett; Hoppe, Clara J. M.; Taylor, Bettina B.; Bracher, Astrid; Hassler, Christel

    2015-04-01

    Photophysiological processes as well as uptake characteristics of iron and inorganic carbon were studied in inshore phytoplankton assemblages of the Western Antarctic Peninsula (WAP) and offshore assemblages of the Drake Passage. Chlorophyll a concentrations and primary productivity decreased from in- to offshore waters. The inverse relationship between low maximum quantum yields of photochemistry in PSII (Fv/Fm) and large sizes of functional absorption cross sections (σPSII) in offshore communities indicated iron-limitation. Congruently, the negative correlation between Fv/Fm values and iron uptake rates across our sampling locations suggest an overall better iron uptake capacity in iron-limited pelagic phytoplankton communities. Highest iron uptake capacities could be related to relative abundances of the haptophyte Phaeocystis antarctica. As chlorophyll a-specific concentrations of humic-like substances were similarly high in offshore and inshore stations, we suggest humic-like substances may play an important role in iron chemistry in both coastal and pelagic phytoplankton assemblages. Regarding inorganic carbon uptake kinetics, the measured maximum short-term uptake rates (Vmax(CO2)) and apparent half-saturation constants (K1/2(CO2)) did not differ between offshore and inshore phytoplankton. Moreover, Vmax(CO2) and K1/2(CO2) did not exhibit any CO2-dependent trend over the natural pCO2 range from 237 to 507 μatm. K1/2(CO2) strongly varied among the sampled phytoplankton communities, ranging between 3.5 and 35.3 μmol L-1 CO2. While in many of the sampled phytoplankton communities, the operation of carbon-concentrating mechanisms (CCMs) was indicated by low K1/2(CO2) values relative to ambient CO2 concentrations, some coastal sites exhibited higher values, suggesting down-regulated CCMs. Overall, our results demonstrate a complex interplay between photophysiological processes, iron and carbon uptake of phytoplankton communities of the WAP and the Drake

  7. Impact of human emotions on physiological characteristics

    NASA Astrophysics Data System (ADS)

    Partila, P.; Voznak, M.; Peterek, T.; Penhaker, M.; Novak, V.; Tovarek, J.; Mehic, Miralem; Vojtech, L.

    2014-05-01

    Emotional states of humans and their impact on physiological and neurological characteristics are discussed in this paper. This problem is the goal of many teams who have dealt with this topic. Nowadays, it is necessary to increase the accuracy of methods for obtaining information about correlations between emotional state and physiological changes. To be able to record these changes, we focused on two majority emotional states. Studied subjects were psychologically stimulated to neutral - calm and then to the stress state. Electrocardiography, Electroencephalography and blood pressure represented neurological and physiological samples that were collected during patient's stimulated conditions. Speech activity was recording during the patient was reading selected text. Feature extraction was calculated by speech processing operations. Classifier based on Gaussian Mixture Model was trained and tested using Mel-Frequency Cepstral Coefficients extracted from the patient's speech. All measurements were performed in a chamber with electromagnetic compatibility. The article discusses a method for determining the influence of stress emotional state on the human and his physiological and neurological changes.

  8. Physiologic Responses to Treadmill and Water Running.

    ERIC Educational Resources Information Center

    Bishop, Phillip A.; And Others

    1989-01-01

    Presents results of a study of the physiological responses of uninjured runners to running on a treadmill and in water. Water running may lessen an injured athlete's rate of deconditioning, but indications are that the metabolic cost of water running is not significantly greater than that of treadmill running. (SM)

  9. Physiological characteristics of international female soccer players.

    PubMed

    Manson, Sarah A; Brughelli, Matt; Harris, Nigel K

    2014-02-01

    The purpose of this study was to investigate the physiological characteristics of Fédération Internationale de Football Association (FIFA) eligible international female soccer players aged 14-36 years and to determine if measures were significantly different for players selected (i.e., starters) to the starting line up for an FIFA tournament as compared with those not selected (i.e., nonstarters). Fifty-one (N = 18 Under 17; N = 18 Under 20; N = 15 Senior) international female soccer players participated in this study. The subjects underwent measurements of anthropometry (height and body mass), lower body strength (isokinetic testing), sprint kinetics and kinematics (nonmotorized treadmill), leg power (unilateral jumping), and maximal aerobic velocity (30:15 intermittent fitness test) during the final preparatory stage for an FIFA event. Outcomes of the age group data indicate that differences in physiological capacities are evident for the Under 17 players as compared with those for the Under 20 and Senior capped international players, suggesting a plateau in the acquisition of physical qualities as players mature. Starters tended to be faster (effect size [ES] = 0.55-1.0, p < 0.05) and have a higher maximal aerobic velocity (ES = 0.78-2.45, p < 0.05), along with greater eccentric leg strength (ES = 0.33-1.67, p < 0.05). Significant differences were detected between starters and nonstarters for isokinetic leg strength (ES = 0.54-1.24, p < 0.05) and maximal aerobic velocity (ES = 0.87, p < 0.05) for Under 17 players, where maximal aerobic velocity was the primary difference between starters and nonstarters (ES = 0.83-2.45, p < 0.05) for the Under 20 and Senior players. Coaches should emphasize the development of speed, maximal aerobic velocity, and leg strength in developing female soccer players. PMID:24476742

  10. Digestive Physiological Characteristics of the Gobiidae

    PubMed Central

    Hur, Sang-Woo; Kim, Shin-Kwon; Kim, Dae-Jung; Lee, Bae-Ik; Park, Su-Jin; Hwang, Hyung-Gyu; Jun, Je-Cheon; Myeong, Jeong-In; Lee, Chi-Hoon; Lee, Young-Don

    2016-01-01

    In this study, we investigated the characteristics of CCK-producing cells and mucus-secreting goblet cells with respect to stomach fish and stomachless fish of the Gobiidae in order to provide a basis for understanding the digestive physiology. Hairychin goby (Sagamia geneionema), which is stomachless fish, the numbers of mucus-secreting goblet cells is highest in the posterior intestine portion (P<0.05), while CCK-producing cells are scattered throughout the intestine. Gluttonous goby (Chasmichthys gulosus), which is stomach fish, mucus-secreting goblet cells are most abundant in the mid intestine portion (P<0.05), whereas CCK-producing cells are observed only in the anterior and mid intestine portion. Trident goby (Tridentiger obscurus) which is stomach fish, mucus-secreting goblet cells were most abundant in the mid intestine portion (P<0.05). CCK-producing cells are found in the anterior and mid intestine portion. Giurine goby, Rhinogobius giurinus which is also stomach fish, the largest number of mucus-secreting goblet cells showed in anterior intestine portion except for esophagus (P<0.05). CCK-producing cells are present only in the anterior and mid intestine portion. In S. geneionema, digestive action occurs in the posterior intestine portion to protect and functions to activate digestion. In contrast, in C. gulosus, T. obscurus and R. giurinus, their digestive action occurs in the anterior and mid intestine portion to protect and functions to activate digestion. Further studies of the modes of food ingestion by these fish, the contents of their digestive tracts, and the staining characteristics of the goblet cells need to be carried out.

  11. FISH PHYSIOLOGY, TOXICOLOGY, AND WATER QUALITY:

    EPA Science Inventory

    Twenty-one participants from Europe, North America and China convened in Chongqing, China, October 12-14, 2005, for the Eighth International Symposium in Fish Physiology, Toxicology and Water Quality. The subject of the meeting was "Hypoxia in vertebrates: Comparisons of terrestr...

  12. FISH PHYSIOLOGY, TOXICOLOGY, AND WATER QUALITY

    EPA Science Inventory

    Scientists from ten countries presented papers at the Fifth International Symposium on Fish Physiology, Toxicology, and Water Quality, which was held on the campus of the city University of Hong Kong on November 10-13, 1998. These Proceedings include 23 papers presented in sessi...

  13. Effects of straw treatment and nitrogen supplementation on digestibility, intake and physiological responses of water intake as well as urine and faecal characteristics.

    PubMed

    Ghasemi, E; Khorvash, M; Ghorbani, G R; Elmamouz, F

    2014-02-01

    This study investigates the effects of feeding diet based on untreated (UT) or ensiled alkali-treated (ET) barley straw with either urea or casein supplementation, on feed intake, digestibility, ruminal pH, water intake and faecal and urinary characteristics. Four sheep fitted with ruminal cannulas were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments. Barley straw was treated by the dry (spraying) method in pH adjusted of hydrogen peroxide (pH 11.5), ensiled for 6 weeks and included at 65% of the diet dry matter (DM). The results showed that straw pH reduced from 11.58 to 8.60 after 6 weeks of ensilage. The ET diet increased average DM digestibility and intake by 19% and 43% respectively. Total water intake was similar across treatments, while the water/DM intake ratio was 23% higher with the UT diet than with the ET one. Ruminal (6.73 vs. 6.84) and faecal (8.67 vs. 9.05) pH decreased but urinary pH (6.14 vs. 8.13) increased as a result of feeding animals on the ET diet compared with the UT diet. Compared with the UT diet, the ET one decreased faecal fibre (12%), moisture (32%) and water holding capacity, while it increased faecal ash (10%) and density (20%). The volume of urine excreted by the sheep fed with the ET diet increased by 67%, but their urine specific gravity (SG) decreased. No significant effects were observed for the dietary N supplementation and interactions between straw type × N supplementation with regard to any of the measured characteristics except for DM intake, which reduced due to the casein supplementation in the ET diet. These results indicate that the alkali treatment and ensilage of barley straw increased digestibility, intake, faecal consistency and urinary pH and dilution but decreased straw alkalinity as well as ruminal and faecal pH.

  14. Physiological characteristics of well-trained junior sprint kayak athletes.

    PubMed

    Borges, Thiago Oliveira; Dascombe, Ben; Bullock, Nicola; Coutts, Aaron J

    2015-07-01

    This study aimed to profile the physiological characteristics of junior sprint kayak athletes (n=21, VO2max 4.1±0.7 L/min, training experience 2.7±1.2 y) and to establish the relationship between physiological variables (VO2max, VO2 kinetics, muscle-oxygen kinetics, paddling efficiency) and sprint kayak performance. VO2max, power at VO2max, power:weight ratio, paddling efficiency, VO2 at lactate threshold, and whole-body and muscle oxygen kinetics were determined on a kayak ergometer in the laboratory. Separately, on-water time trials (TT) were completed over 200 m and 1000 m. Large to nearly perfect (-.5 to -.9) inverse relationships were found between the physiological variables and on-water TT performance across both distances. Paddling efficiency and lactate threshold shared moderate to very large correlations (-.4 to -.7) with 200- and 1000-m performance. In addition, trivial to large correlations (-.11 to -.5) were observed between muscle-oxygenation parameters, muscle and whole-body oxygen kinetics, and performance. Multiple regression showed that 88% of the unadjusted variance for the 200-m TT performance was explained by VO2max, peripheral muscle deoxygenation, and maximal aerobic power (P<.001), whereas 85% of the unadjusted variance in 1000-m TT performance was explained by VO2max and deoxyhemoglobin (P<.001). The current findings show that well-trained junior sprint kayak athletes possess a high level of relative aerobic fitness and highlight the importance of the peripheral muscle metabolism for sprint kayak performance, particularly in 200-m races, where finalists and nonfinalists are separated by very small margins. Such data highlight the relative aerobic-fitness variables that can be used as benchmarks for talent-identification programs or monitoring longitudinal athlete development. However, such approaches need further investigation.

  15. Physiological characteristics of elite female basketball players.

    PubMed

    Smith, H K; Thomas, S G

    1991-12-01

    Successful performance in international basketball competition requires an appreciation of the physical demands of the sport and the capacities of the team to respond to those demands. Optimal performance now requires a combination of technical and tactical abilities as well as a high degree of physical fitness. The objectives of this study were to assess physiological components considered important to game performance in players selected to the national team roster in 1988 or 1989, and to use this information to describe the team and positional profiles. Data obtained from maximal treadmill tests, anthropometry, sprints, isokinetic dynamometry, and other tasks reflected those qualities required of elite players. In relation to previously reported data, the athletes were generally taller and heavier and had higher maximal aerobic power than international and college players of 7 to 10 years ago. The data can also be used to identify target standards for current and prospective team members.

  16. The Clinical Physiology of Water Metabolism

    PubMed Central

    Weitzman, Richard E.; Kleeman, Charles R.

    1979-01-01

    Water balance is tightly regulated within a tolerance of less than 1 percent by a physiologic control system located in the hypothalamus. Body water homeostasis is achieved by balancing renal and nonrenal water losses with appropriate water intake. The major stimulus to thirst is increased osmolality of body fluids as perceived by osmoreceptors in the anteroventral hypothalamus. Hypovolemia also has an important effect on thirst which is mediated by arterial baroreceptors and by the renin-angiotensin system. Renal water loss is determined by the circulating level of the antidiuretic hormone, arginine vasopressin (AVP). AVP is synthesized in specialized neurosecretory cells located in the supraoptic and paraventricular nuclei in the hypothalamus and is transported in neurosecretory granules down elongated axons to the posterior pituitary. Depolarization of the neurosecretory neurons results in the exocytosis of the granules and the release of AVP and its carrier protein (neurophysin) into the circulation. AVP is secreted in response to a wide variety of stimuli. Change in body fluid osmolality is the most potent factor affecting AVP secretion, but hypovolemia, the renin-angiotensin system, hypoxia, hypercapnia, hyperthermia and pain also have important effects. Many drugs have been shown to stimulate the release of AVP as well. Small changes in plasma AVP concentration of from 0.5 to 4 μU per ml have major effects on urine osmolality and renal water handling. ImagesFigure 5.Figure 12.Figure 15.Figure 16. PMID:394480

  17. [Seed growth characteristics of Ginkgo biloba and its physiological change].

    PubMed

    Wang, J; Wang, J; Xin, X

    2000-08-01

    The length, width, volume and weight of Ginkgo biloba seed were measured, and the concentrations of water, sugars, fatty acids and amino acids in seed growth process were analyzed. A typical "S" seed growth curve was found, and the length, width, volume, weight and absolute water content all showed the similar changes during growing period. With the growing of ssed, the concentrations of physiological substances in seeds showed regular changes and had their own characteristics. The total amount of sugars appeared to be an increasing trend at the later stage of seed growth, indicating that sugars are the main nutrition substance accumulated in seeds. The concentrations of various substances in matured seeds were starch 8.4%, glucose 6.7%, fructose 4.2%, polysaccharide 0.02%, disaccharide 0.01%, myristic acid 10.6%, palmitic acid 4.1%, flax acid 2.4%, stearic acid 1.9%, oleic acid 1.1%, and linoleic acid 0.4%. Fifteen types of free amino acids were detected in matured seeds, with total content of 1.56 g.100 g-1FW. Among them, lysine aspartic acid, alanine, arginine, histidine, glutamic acid, and isoleucine were dominant, and their concentrations were 0.287%, 0.163%, 0.136%, 0.133%, 0.123%, 0.115%, 0.095%, respectively.

  18. Photosynthetic Physiological Characteristics of Gazania rigens L. Under Drought Stress

    NASA Astrophysics Data System (ADS)

    Gao, T. T.; Zheng, S. W.; Zhou, X. H.; Wang, D. X.; Lu, X. P.

    2016-08-01

    To investigate the responses of photosynthetic physiological characteristics of Gazania rigens L. to drought stress, the changes of three cultivars (‘Xingbai’, ‘XH’ and ‘Hongwen’) photosynthetic values under drought stress were determined via LI-6400 portable photosynthesis analyzer (LI-COR, USA), and the relationships between photosynthesis and drought resistance of each cultivar were analyzed. The results showed that, three cultivars net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), and light use efficiency (LUE) value indicated the trend of decreasing gradually and there existed significant reduction in Pn and Gs values. There were extremely negative significant correlations between drought stress treatment days and Pn, Gs, Tr, water use efficiency (WUE) and LUE values. A small amount of leaves began to turn soft and yellow after drought stress treatment for 10 days, but they could recover to grow quickly after rehydration. The Pn values of ‘Hongwen’ decreased quickly and changed in a large range, so it had a poor resistance; the Pn values of ‘Xingbai’ decreased slowly and changed in a small range, so it had a strong resistance; while the changes of their hybrids -‘XH’ were between its parents. This research would provide a theoretical basis for gazania resistance cultivar breeding and application in landscape.

  19. Physical and chemical characteristics of pitaya fruits at physiological maturity.

    PubMed

    Ortiz, T A; Takahashi, L S A

    2015-01-01

    The aim of this study was to analyze the physical and chemical characteristics of the maturation process of pitaya fruit (Hylocereus undatus) to identify indicators that can be used to determine the point of physiological maturity and establish the optimal timing of physiological maturity for harvesting the fruit. A completely randomized experimental design was employed and four biological repeats were performed. Physiological maturity was assessed using various physical characteristics: longitudinal length (LL), equatorial diameter (ED), pericarp thickness (PeT), pulp thickness (PuT), fruit mass (FM), pulp mass (PuM), pericarp mass (PeM), pericarp percentage (%Pe), pulp percentage (%Pu), pulp/pericarp ratio (Pu/Pe), pericarp color index (CI), hue color angle (h°), lightness index (L*), chroma (C*), blue-yellow variation (b*), and green-red variation (a*). Additionally, chemical characteristics such as soluble solid content (SS), titratable acidity (TA), SS/TA ratio, and pH were screened. The data were statistically analyzed by fitting regression models and computing Pearson's correlation coefficients (P < 0.05). Physiological maturity in pitaya fruits occurred between the 30th and 32nd days after anthesis, and this proved to be the optimal period for harvest. At this time, the fruit was completely red with high SS, and had the recommended values of TA, pH, and SS/TA ratio. During this period, ED, PuT, FM, PuM, %Pu, and Pu/Pe increased while PeT, PeM, and %Pe fell; these changes are considered desirable by producers and/or consumers. PuM was the variable that displayed more strong's association with other variables in the analysis. PMID:26600501

  20. Physical and chemical characteristics of pitaya fruits at physiological maturity.

    PubMed

    Ortiz, T A; Takahashi, L S A

    2015-11-19

    The aim of this study was to analyze the physical and chemical characteristics of the maturation process of pitaya fruit (Hylocereus undatus) to identify indicators that can be used to determine the point of physiological maturity and establish the optimal timing of physiological maturity for harvesting the fruit. A completely randomized experimental design was employed and four biological repeats were performed. Physiological maturity was assessed using various physical characteristics: longitudinal length (LL), equatorial diameter (ED), pericarp thickness (PeT), pulp thickness (PuT), fruit mass (FM), pulp mass (PuM), pericarp mass (PeM), pericarp percentage (%Pe), pulp percentage (%Pu), pulp/pericarp ratio (Pu/Pe), pericarp color index (CI), hue color angle (h°), lightness index (L*), chroma (C*), blue-yellow variation (b*), and green-red variation (a*). Additionally, chemical characteristics such as soluble solid content (SS), titratable acidity (TA), SS/TA ratio, and pH were screened. The data were statistically analyzed by fitting regression models and computing Pearson's correlation coefficients (P < 0.05). Physiological maturity in pitaya fruits occurred between the 30th and 32nd days after anthesis, and this proved to be the optimal period for harvest. At this time, the fruit was completely red with high SS, and had the recommended values of TA, pH, and SS/TA ratio. During this period, ED, PuT, FM, PuM, %Pu, and Pu/Pe increased while PeT, PeM, and %Pe fell; these changes are considered desirable by producers and/or consumers. PuM was the variable that displayed more strong's association with other variables in the analysis.

  1. Genetics of water use physiology in locally adapted Arabidopsis thaliana.

    PubMed

    Mojica, Julius P; Mullen, Jack; Lovell, John T; Monroe, J Grey; Paul, John R; Oakley, Christopher G; McKay, John K

    2016-10-01

    Identifying the genetic basis of adaptation to climate has long been a goal in evolutionary biology and has applications in agriculture. Adaptation to drought represents one important aspect of local adaptation, and drought is the major factor limiting agricultural yield. We examined local adaptation between Sweden and Italy Arabidopsis thaliana ecotypes, which show contrasting levels of water availability in their local environments. To identify quantitative trait loci (QTL) controlling water use physiology traits and adaptive trait QTL (genomic regions where trait QTL and fitness QTL colocalize), we performed QTL mapping on 374F9 recombinant inbred lines in well-watered and terminal drought conditions. We found 72 QTL (32 in well-watered, 31 in drought, 9 for plasticity) across five water use physiology traits: δ(13)C, rosette area, dry rosette weight, leaf water content and percent leaf nitrogen. Some of these genomic regions colocalize with fitness QTL and with other physiology QTL in defined hotspots. In addition, we found evidence of both constitutive and inducible water use physiology QTL. Finally, we identified highly divergent candidate genes, in silico. Our results suggest that many genes with minor effects may influence adaptation through water use physiology and that pleiotropic water use physiology QTL have fitness consequences.

  2. Genetics of water use physiology in locally adapted Arabidopsis thaliana.

    PubMed

    Mojica, Julius P; Mullen, Jack; Lovell, John T; Monroe, J Grey; Paul, John R; Oakley, Christopher G; McKay, John K

    2016-10-01

    Identifying the genetic basis of adaptation to climate has long been a goal in evolutionary biology and has applications in agriculture. Adaptation to drought represents one important aspect of local adaptation, and drought is the major factor limiting agricultural yield. We examined local adaptation between Sweden and Italy Arabidopsis thaliana ecotypes, which show contrasting levels of water availability in their local environments. To identify quantitative trait loci (QTL) controlling water use physiology traits and adaptive trait QTL (genomic regions where trait QTL and fitness QTL colocalize), we performed QTL mapping on 374F9 recombinant inbred lines in well-watered and terminal drought conditions. We found 72 QTL (32 in well-watered, 31 in drought, 9 for plasticity) across five water use physiology traits: δ(13)C, rosette area, dry rosette weight, leaf water content and percent leaf nitrogen. Some of these genomic regions colocalize with fitness QTL and with other physiology QTL in defined hotspots. In addition, we found evidence of both constitutive and inducible water use physiology QTL. Finally, we identified highly divergent candidate genes, in silico. Our results suggest that many genes with minor effects may influence adaptation through water use physiology and that pleiotropic water use physiology QTL have fitness consequences. PMID:27593459

  3. Effects of Deployment on Musculoskeletal and Physiological Characteristics and Balance.

    PubMed

    Nagai, Takashi; Abt, John P; Sell, Timothy C; Keenan, Karen A; McGrail, Mark A; Smalley, Brian W; Lephart, Scott M

    2016-09-01

    Despite many nonbattle injuries reported during deployment, few studies have been conducted to evaluate the effects of deployment on musculoskeletal and physiological characteristics and balance. A total of 35 active duty U.S. Army Soldiers participated in laboratory testing before and after deployment to Afghanistan. The following measures were obtained for each Soldier: shoulder, trunk, hip, knee, and ankle strength and range of motion (ROM), balance, body composition, aerobic capacity, and anaerobic power/capacity. Additionally, Soldiers were asked about their physical activity and load carriage. Paired t tests or Wilcoxon tests with an α = 0.05 set a priori were used for statistical analyses. Shoulder external rotation ROM, torso rotation ROM, ankle dorsiflexion ROM, torso rotation strength, and anaerobic power significantly increased following deployment (p < 0.05). Shoulder extension ROM, shoulder external rotation strength, and eyes-closed balance (p < 0.05) were significantly worse following deployment. The majority of Soldiers (85%) engaged in physical activity. In addition, 58% of Soldiers reported regularly carrying a load (22 kg average). The deployment-related changes in musculoskeletal and physiological characteristics and balance as well as physical activity and load carriage during deployment may assist with proper preparation with the intent to optimize tactical readiness and mitigate injury risk. PMID:27612352

  4. Profiling in basketball: physical and physiological characteristics of elite players.

    PubMed

    Ostojic, Sergej M; Mazic, Sanja; Dikic, Nenad

    2006-11-01

    The purpose of this study was to describe structural and functional characteristics of elite Serbian basketball players and to evaluate whether players in different positional roles have different physical and physiological profiles. Five men's basketball teams participated in the study and competed in the professional First National League. Physiological measurements were taken of 60 players during the final week of their preparatory training for competition. According to positional roles, players were categorized as guards (n = 20), forwards (n = 20), and centers (n = 20). Guards were older (p < 0.01) and more experienced (p < 0.01) as compared with both forwards and centers. Centers were taller and heavier than guards and forwards (p < 0.01), whereas forwards had significantly higher height and weight than guards (p < 0.01). Centers had more body fat (p < 0.01) as compared with forwards and guards. Also, centers had significantly lower estimated VO(2)max values (p < 0.01) compared with forwards and guards. In addition, the highest heart rate frequencies during the last minute of the shuttle run test were lower in guards (p < 0.01) as compared with forwards and centers. Vertical jump power was significantly higher in centers (p < 0.01) as compared with guards. The results of the present study demonstrate that a strong relationship exists between body composition, aerobic fitness, anaerobic power, and positional roles in elite basketball.

  5. Physiological and physical characteristics of elite dragon boat paddlers.

    PubMed

    Ho, Sarah R; Smith, Richard M; Chapman, Philip G; Sinclair, Peter J; Funato, Kazuo

    2013-01-01

    The objectives of this study were to profile the physiological and physical characteristics of elite dragon boat paddlers, to identify characteristics that predict race performance and to quantify the metabolic energy contributions to simulated 200-m and 500-m dragon boat racing. Eleven, national level, male, Japanese dragon boat paddlers completed a battery of tests on a paddling ergometer including an incremental maximal aerobic capacity test, a 2-minute maximal accumulated oxygen deficit (MAOD) test, and simulated 200-m and 500-m races. A physiological and physical profile of subjects was compiled. Results showed that 200-m race performance correlated with flexed arm girth and excess postexercise oxygen consumption (EPOC) measured in the 30 minutes after the MAOD test, whereas 500-m race performance correlated with body fat percentage, relaxed and flexed arm girth, MAOD, EPOC, and peak power during the MAOD test. Stepwise multiple regression revealed that flexed arm girth was the most powerful predictor of 200-m and 500-m race performance, followed by EPOC with the combination of these 2 factors able to explain 74% and 68% of the variance in 200-m and 500-m race performance, respectively. Aerobic energy contributions for 200-m (50 seconds) and 500-m (1 minute 50 seconds) races were (mean (95% confidence intervals)) 52.1% (range, 47.4-56.8%) and 67.5% (range, 60.1-77.8%), respectively. In conclusion, coaches should develop training programs targeted at developing upper-body musculature and increasing anaerobic capacity because these factors are the strongest predictors of 200-m and 500-m race performance. Given the substantial aerobic energy contributions even for a 200-m race event, coaches should aim to increase the maximal aerobic capacity of the paddler in preparation for both 200-m and 500-m events.

  6. Physiological characteristics of the biocontrol yeast Pichia anomala J121.

    PubMed

    Fredlund, Elisabeth; Druvefors, Ulrika; Boysen, Marianne E; Lingsten, Karl-Johan; Schnürer, Johan

    2002-08-01

    The yeast Pichia anomala J121 prevents mold spoilage and enhances preservation of moist grain in malfunctioning storage systems. Development of P. anomala J121 as a biocontrol agent requires in-depth knowledge about its physiology. P. anomala J121 grew under strictly anaerobic conditions, at temperatures between 3 degrees C and 37 degrees C, at pH values between 2.0 and 12.4, and at a water activity of 0.92 (NaCl) and 0.85 (glycerol). It could assimilate a wide range of C- and N-sources and produce killer toxin. A selective medium containing starch, nitrate, acetic acid, and chloramphenicol was developed for P. anomala. P. anomala was equally sensitive as Candida albicans to common antifungal compounds. Growth ability at a range of environmental conditions contributes to the competitive ability of the biocontrol yeast P. anomala J121. PMID:12702290

  7. The Clinical Physiology of Water Metabolism

    PubMed Central

    Weitzman, Richard E.; Kleeman, Charles R.

    1980-01-01

    Hyperosmolality occurs when there are defects in the two major homeostatic mechanisms required for water balance—thirst and arginine vasopressin (AVP) release. In this situation hypotonic fluids are lost in substantial quantities causing depletion of both intracellular and extracellular fluid compartments. Patients with essential hypernatremia have defective osmotically stimulated AVP release and thirst but may have intact mechanisms for AVP release following hypovolemia. Hyperosmolality can also be seen in circumstances in which impermeable solutes are present in excessive quantities in extracellular fluid. Under these conditions there is cellular dehydration and the serum sodium may actually be reduced by water drawn out of cells along an osmotic gradient. Hyposmolality and hyponatremia may be seen in a variety of clinical conditions. Salt depletion, states in which edema occurs and the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) may all produce severe dilution of body fluids resulting in serious neurologic disturbances. The differential diagnosis of these states is greatly facilitated by careful clinical assessment of extracellular fluid volume and by determination of urine sodium concentration. Treatment of the hyposmolar syndromes is contingent on the pathophysiology of the underlying disorder; hyponatremia due to salt depletion is treated with infusions of isotonic saline whereas mild hyponatremia in cirrhosis and ascites is best treated with water restriction. Severe symptomatic hyponatremia due to SIADH is treated with hypertonic saline therapy, sometimes in association with intravenous administration of furosemide. Less severe, chronic cases may be treated with dichlormethyltetracycline which blocks the action of AVP on the collecting duct. ImagesFigure 43.Figure 44.Figure 47. PMID:6246683

  8. [Effects of drought stress on the root growth and development and physiological characteristics of peanut].

    PubMed

    Ding, Hong; Zhang, Zhi-Meng; Dai, Liang-Xiang; Kang, Tao; Ci, Dun-Wei; Song, Wen-Wu

    2013-06-01

    Taking two peanut varieties Huayu 17 and Tangke 8 as test objects, a soil column culture experiment was conducted in a rainproof tank to study the peanut root morphological development and physiological characteristics at late growth stages under moderate drought and well-watered conditions. Tanke 8 had more developed root system and higher yield and drought coefficient, while Huayu 17 had poorer root adaptability to drought stress. For the two varieties, their root length density and root biomass were mainly distributed in 0-40 cm soil layer, whereas their root traits differed in the same soil layer. The total root length, total root surface area, and total root volume of Huayu 17 at each growth stage were smaller under drought stress than under well-balanced water treatment, while these root characteristics of Tangke 8 under drought stress only decreased at flowering-pegging stage. Drought stress increased the root biomass, surface area, and volume of the two varieties in 20-40 cm soil layer, but decreased these root traits in the soil layers below 40 cm. Under drought stress, the root activity of the two varieties in the soil layers below 40 cm at pod filling stage decreased, and the decrement was larger for Huayu 17. The differences in the root system development and physiological characteristics of the two varieties at late growth stages under drought stress suggested that the root system of the two varieties had different water absorption and utilization under drought stress.

  9. Physiological and anthropometric characteristics of amateur rugby league players

    PubMed Central

    Gabbett, T.

    2000-01-01

    Objectives—To investigate the physiological and anthropometric characteristics of amateur rugby league players. Methods—Thirty five amateur rugby league players (19 forwards and 16 backs) were measured for height, body mass, percentage body fat (sum of four skinfolds), muscular power (vertical jump), speed (10 m and 40 m sprint), and maximal aerobic power (multistage fitness test). Data were also collected on match frequency, training status, playing experience, and employment related physical activity levels. Results—The 10 m and 40 m sprint, vertical jump, percentage body fat, and multistage fitness test results were 20–42% poorer than previously reported for professional rugby league players. Compared with forwards, backs had significantly (p<0.01) lower body mass (79.7 (74.7–84.7) kg v 90.8 (86.2–95.4) kg) and significantly (p<0.01) greater speed during the 40 m sprint (6.45 (6.35–6.55) v 6.79 (6.69–6.89) seconds). Values for percentage body fat, vertical jump, 10 m sprint, and maximal aerobic power were not significantly different (p>0.05) between forwards and backs. When compared with professional rugby league players, the training status of amateur rugby league players was 30–53% lower, with players devoting less than three hours a week to team training sessions and about 30 minutes a week to individual training sessions. The training time devoted to the development of muscular power (about 13 minutes a week), speed (about eight minutes a week), and aerobic fitness (about 34 minutes a week) did not differ significantly (p>0.05) between forwards and backs. At the time of the field testing, players had participated, on average, in one 60 minute match every eight days. Conclusions—The physiological and anthropometric characteristics of amateur rugby league players are poorly developed. These findings suggest that position specific training does not occur in amateur rugby league. The poor fitness of non-elite players may be due to a low

  10. Methanogenic archaea database containing physiological and biochemical characteristics.

    PubMed

    Jabłoński, Sławomir; Rodowicz, Paweł; Łukaszewicz, Marcin

    2015-04-01

    The methanogenic archaea are a group of micro-organisms that have developed a unique metabolic pathway for obtaining energy. There are 150 characterized species in this group; however, novel species continue to be discovered. Since methanogens are considered a crucial part of the carbon cycle in the anaerobic ecosystem, characterization of these micro-organisms is important for understanding anaerobic ecology. A methanogens database (MDB; http://metanogen.biotech.uni.wroc.pl/), including physiological and biochemical characteristics of methanogens, was constructed based on the descriptions of isolated type strains. Analysis of the data revealed that methanogens are able to grow from 0 to 122 °C. Methanogens growing at the same temperature may have very different growth rates. There is no clear correlation between the optimal growth temperature and the DNA G+C content. The following substrate preferences are observed in the database: 74.5% of archaea species utilize H2+CO2, 33% utilize methyl compounds and 8.5% utilize acetate. Utilization of methyl compounds (mainly micro-organisms belonging to the genera Methanosarcina and Methanolobus ) is seldom accompanied by an ability to utilize H2+CO2. Very often, data for described species are incomplete, especially substrate preferences. Additional research leading to completion of missing information and development of standards, especially for substrate utilization, would be very helpful.

  11. Body composition and physiological characteristics of law enforcement officers.

    PubMed

    Spitler, D L; Jones, G; Hawkins, J; Dudka, L

    1987-12-01

    The physical work capacity, body composition, and physiological characteristics of 12 law enforcement officers (9 males, 3 females) were measured. Subjects included a representative sample from the occupational categories of detective, staff, investigative and patrol officer. Mean maximal oxygen uptake of the men was 42.1 +/- 8.9 ml.kg-1min-1 with mean values of 41.5 +/- 8.7 ml.kg-1min-1 for the women. Measurement of body composition indicated an average of 24.4 +/- 7.1% body fat for the men and 30.9 +/- 1.2% for the women. Muscular power, strength, and endurance as measured by isolated limb flexion-extension movement and fitness test performance was considered average with no excessive bilateral differences. The results of this study were compared with other investigations of law enforcement officers of similar age groups. The officers displayed average or above health and physical fitness scores for their age classification and were able to complete all police task-oriented tests.

  12. Physiological Effects of Trace Elements and Chemicals in Water

    ERIC Educational Resources Information Center

    Varma, M. M.; And Others

    1976-01-01

    The physiological effects on humans and animals of trace amounts of organic and unorganic pollutants in natural and waste waters are examined. The sensitivity of particular organs and species is emphasized. Substances reviewed include mercury, arsenic, cadmium, lead, chromium, fluorides, nitrates and organics, including polychlounated biphenyls.…

  13. SYMPOSIUM IN ITALY: FISH PHYSIOLOGY, TOXICOLOGY, AND WATER QUALITY

    EPA Science Inventory

    Scientists from Europe, North America and South America convened in Capri, Italy, April 24-28, 2006 for the Ninth International Symposium on Fish Physiology, Toxicology, and Water Quality. The subject of the meeting was Eutrophication: The toxic effects of ammonia, nitrite and th...

  14. The Characteristic Curves of Water

    NASA Astrophysics Data System (ADS)

    Neumaier, Arnold; Deiters, Ulrich K.

    2016-09-01

    In 1960, E. H. Brown defined a set of characteristic curves (also known as ideal curves) of pure fluids, along which some thermodynamic properties match those of an ideal gas. These curves are used for testing the extrapolation behaviour of equations of state. This work is revisited, and an elegant representation of the first-order characteristic curves as level curves of a master function is proposed. It is shown that Brown's postulate—that these curves are unique and dome-shaped in a double-logarithmic p, T representation—may fail for fluids exhibiting a density anomaly. A careful study of the Amagat curve (Joule inversion curve) generated from the IAPWS-95 reference equation of state for water reveals the existence of an additional branch.

  15. [Effect of red and blue spectrum on photosynthesis physiological characteristics of two ecotypes of Leymus chinensis].

    PubMed

    Zhou, Chan; Yang, Yun-Fei; Wang, Kun

    2008-07-01

    Photosynthesis physiological characteristics of two ecotypes of Leymus chinensis were studied under different red and blue light excitation by LED red and blue lamp-house. Photosynthesis did not carry on under red and blue light of 50 micromol x m(-2) x s(-1). When red and blue light intensity was increased, photosynthesis rate, stoma limit value and transpiration rate of the two ecotypes of Leymus chinensis were all increased. But photosynthesis rate stopped increasing under red and blue light of 1 150 micromol x m(-2) x s(-1) for grey-green ecotype Leymus chinensis and of 907 micromol x m(-2) x s(-1) for yellow-green ecotype Leymus chinensis, which is known as light saturation. And the effect of blue light on photosynthesis became weaker than red light under higher light intensity. Increasing light intensity can promote plant photosynthesis rate in the range of low light intensity. But when light intensity reaches light saturation, photosynthesis rate does not increases but decreases. Because though light quantum numbers is increasing, the numbers of coloring mater does not change and is saturated. On the other hand, when the light intensity is of light saturation, the stoma limit value was increased and the transpiration rate was decreased in order to reduce water waste. When light intensity reaches the value that plant can bear, the plant will automatically close stoma in order to decrease transpiration and to save water. Plant balances every physiological index and makes sure that physiology damage is the least and production is the greatest. Although grey-green ecotype Leymus chinensis has lower stoma limit and higher water waste, it also has higher photosynthesis rate than yellow-green ecotype Leymus chinensis. And the photosynthesis capability and physiology adaptation of grey-green ecotype Leymus chinensis is greater than that of yellow-green ecotype Leymus chinensis.

  16. Human red blood cells' physiological water exchange with the plasma.

    PubMed

    Kargol, M; Kargol, A; Przestalski, M; Siedlecki, J; Karpińska, M; Rogowski, M

    2005-01-01

    In the present paper, fundamental issues related to the mechanisms of human red blood cells' physiological water exchange with the plasma (for the stationary conditions) have been discussed. It has been demonstrated, on the basis of mechanistic transport equations for membrane transport that red blood cells are capable of exchanging considerable amounts of water with the plasma. Water absorption is osmosis-driven, and its removal occurs according to the hydromechanics principle, i.e. is driven by the turgor pressure of red blood cells. This newly-acquired knowledge of these issues may appear highly useful for clinical diagnosis of blood diseases and blood circulation failures. PMID:16358974

  17. [Effect of high hydrostatic pressure on microbial physiological characteristics].

    PubMed

    Li, Zong-Jun; Xu, Jian-Xing

    2005-08-01

    Physiological characterizations of Listeria monocytogenes NCTC 11994 and Escherichia coli ATCC 80739 have deeply changed by high hydrostatic pressure. The results showed that counts of both microbial strains decreased 7 log cfu at 400MPa, 10 min. Pressure treatments also resulted in change of Intracellular pH value, lowed membrane potential, have internal potassium filtered out, and decreased ATP concentration.

  18. Differential responses of grapevine rootstocks to water stress are associated with adjustments in fine root hydraulic physiology and suberization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water deficits are known to alter fine root structure and function, but little is known about how these responses contribute to differences in drought resistance across grapevine rootstocks. We studied how water deficit affects root anatomical and physiological characteristics in two grapevine root...

  19. The water absorption response: a behavioral assay for physiological processes in terrestrial amphibians.

    PubMed

    Hillyard, S D; Hoff, K S; Propper, C

    1998-01-01

    Terrestrial amphibians take up water by abducting the hind limbs and pressing a specialized portion of the ventral skin to a moist surface, using a characteristic behavior called the water absorption response. An assay of the water absorption response was used to quantify physiological factors associated with thirst and water uptake. Dramatic changes in the water absorption response resulted from subtle changes in hydration state and from altering the reserve water supply in the urinary bladder. The water absorption response could be induced by intraperitoneal and intracerebroventricular injection of angiotensin II, demonstrating that components of the renin-angiotensin system on both sides of the blood-brain barrier have a dipsogenic function in amphibians. These experiments also demonstrated that the water absorption response could be influenced by changes in barometric pressure. Toads avoided the water absorption response on hyperosmotic substrates, and behavioral experiments showed that the amphibian skin served a sensory function similar to that of the lingual epithelium of mammals. The water absorption response assay has enormous potential as a tool for the investigation of physiological processes and sensory capabilities of amphibians.

  20. [Effects of flooding on the photosynthetic physiology characteristics of Pterocarya stenoptera seedlings].

    PubMed

    Wang, Chao-Ying; Li, Chang-Xiao; Zhang, Ye

    2013-03-01

    Three water treatments (control, CK; continuous flooding, CF; and periodic flooding, PF) were installed to simulate the soil moisture change of the riparian zone in the Three Gorges Reservoir (TGR) region of China to study the physiological and ecological adaptation mechanisms of the native plant species Pterocarya stenoptera seedlings to the soil moisture change. All the water treatments had significant effects on the photosynthesis, biomass accumulation, and growth of the P. stenoptera seedlings. As compared with those in CK, the seedling's net photosynthetic rate (Pn) and stomatal conductance (gs) in treatments CF and PF were significantly lower while the intercellular carbon dioxide concentration was significantly higher, and the Pn and gs in CF and PF declined initially followed by a gradual recovery or tended to be stable. With the extension of treatment time, the total biomass and root-, stem-, and leaf biomass, plant height, and basal diameter in CF and PF all presented an increasing trend. Throughout the experimental period, the total biomass, root- and leaf biomass, and plant height in CF and PF and the stem biomass in PF were significantly lower than those in CK, whereas the stem biomass in CF had no significant difference with that in CK, though the basal diameter in CF was significantly higher than that in CK. It was suggested that the P. stenoptera seedlings had the physiological and ecological characteristics of tolerating flooding rather than flooding-drought alteration.

  1. Physiological responses of Chinese longsnout catfish to water temperature

    NASA Astrophysics Data System (ADS)

    Han, Dong; Xie, Shouqi; Zhu, Xiaoming; Yang, Yunxia

    2011-05-01

    We evaluated the effect of water temperature on the growth and physiology of the Chinese longsnout catfish ( Leiocassis longirostris Günther). The fish were reared at four temperatures (20, 25, 30, and 35°C) and sampled on days 7, 20, and 30. We measured plasma levels of insulin, free thyroxine (FT4), free 3,5,3'-triiodothyronine (FT3), lysozyme and leukocyte phagocytic activity. The optimum water temperature for growth was 27.7°C. The plasma levels of insulin and FT4 declined significantly ( P<0.05) on day 30 at temperatures above 20°C. Lysozyme activity was significantly ( P<0.05) lower at 25°C than at other temperatures. We conclude that final weight, insulin, FT4, and lysozyme were significantly affected by water temperature.

  2. Physiology

    ERIC Educational Resources Information Center

    Kay, Ian

    2008-01-01

    Underlying recent developments in health care and new treatments for disease are advances in basic medical sciences. This edition of "Webwatch" focuses on sites dealing with basic medical sciences, with particular attention given to physiology. There is a vast amount of information on the web related to physiology. The sites that are included here…

  3. Physiological characteristics of mercury uptake by two estuarine species

    USGS Publications Warehouse

    Luoma, S.N.

    1977-01-01

    Rapid uptake and slow loss of Hg will result from short exposures of some organisms to this metal, due to the transformation of Hg to a slowly exchanging form within the organisms. The extent of the difference between exposure time and depuration time will depend upon the rate of transformation during uptake. For the polychaete worm Neanthes succinea and the shrimp Palaemon debilis such transformations are extremely rapid. The exchange of Hg from the slowly exchanging compartment is similar among a wide variety of species. Thus, interspecies differences in susceptibility to Hg may be determined by differences in biochemical transformation rates and physiological permeability to the metal. ?? 1977 Springer-Verlag.

  4. Physiological and acoustic characteristics of the male music theatre voice.

    PubMed

    Bourne, Tracy; Garnier, Maëva; Samson, Adeline

    2016-07-01

    Six male music theatre singers were recorded in three different voice qualities: legit and two types of belt ("chesty" and "twangy"), on two vowels ([e] and [ɔ]), at four increasing pitches in the upper limit of each singer's belt range (∼250-440 Hz). The audio signal, the electroglottographic (EGG) signal, and the vocal tract impedance were all measured simultaneously. Voice samples were analyzed and then evaluated perceptually by 16 expert listeners. The three qualities were produced with significant differences at the physiological, acoustical, and perceptual levels: Singers produced belt qualities with a higher EGG contact quotient (CQEGG) and greater contacting speed quotient (Qcs), greater sound pressure level (SPL), and energy above 1 kHz (alpha ratio), and with higher frequencies of the first two vocal tract resonances (fR1, fR2), especially in the upper pitch range when compared to legit. Singers produced the chesty belt quality with higher CQEGG, Qcs, and SPL values and lower alpha ratios over the whole belt range, and with higher fR1 at the higher pitch range when compared to twangy belt. Consistent tuning of fR1 to the second voice harmonic (2f0) was observed in all three qualities and for both vowels. Expert listeners tended to identify all qualities based on the same acoustical and physiological variations as those observed in the singers' intended qualities. PMID:27475183

  5. Apparent water permeability as a physiological parameter in crustaceans

    PubMed

    Rasmussen; Andersen

    1996-01-01

    This article reviews the use of apparent water permeability (AWP) calculated from measurements of isotope-labelled water flux as a physiological estimate of whole-body water permeability in aquatic invertebrates. The rationale and practices of AWP calculations are described in an Appendix. AWP calculations have provided a wealth of information. However, the validity of the method and therefore also of the information obtained have been questioned. Consequently, the use of AWP data in discussions of osmotic and fluid homeostatic questions in aquatic invertebrates is limited. This article reviews three decades of published experiments in which measurements of isotope-labelled water fluxes were used to estimate water permeability in aquatic invertebrates. Data on 24 species of arthropod, most of them decapod crustaceans, are presented. The combined data indicate that the results obtained by different investigators on the same species show good agreement, even though different tracers and experimental methods have been applied. When available, results from other kinds of studies were used to evaluate the results obtained using the AWP measurements. The various results demonstrate that AWP is influenced not only by natural environmental factors, such as salinity and temperature, and by anthropogenic factors, such as potentially toxic trace metals, but that it is also regulated by intrinsic factors, such as ecdysis and life cycle stage. The results obtained can often be explained as effects of components of the habitat of the animal. Accordingly, studies on variations in AWP contribute to our understanding of the different physiological strategies used by species living in a changing environment. We conclude that calculations of AWP offer reliable, relevant physiological data in a range of crustacean species, as long as methodological limitations and uncertainties are kept in mind. In addition, we propose some possible new ways of applying AWP calculations to marine

  6. Morphological and physiological characteristics of dermal photoreceptors in Lymnaea stagnalis

    PubMed Central

    Takigami, Satoshi; Sunada, Hiroshi; Horikoshi, Tetsuro; Sakakibara, Manabu

    2014-01-01

    Dermal photoreceptors located in the mantle of Lymnaea stagnalis were histologically and physiologically characterized. Our previous study demonstrated that the shadow response from dermal photoreceptors induces the whole-body withdrawal response. Through the interneuron, RPeD11, we detected that the light-off response indirectly originated from a dermal photoreceptor. Previous observations, based on behavioral pharmacology, revealed that cyclic guanosine monophosphate acts as a second messenger in the dermal photoreceptor. Furthermore, gastropods possess dermal photoreceptors containing rhodopsin, as a photopigment, and another photo-sensitive protein, arrestin, responsible for terminating the light response. Thus, we chose three antibodies, anti-cGMP, anti-rhodopsin, and anti-β-arrestin, to identify the dermal photoreceptor molecules in Lymnaea mantle. Extracellular recording, using a suction electrode on the mantle, revealed a light off-response from the right parietal nerve. Overlapping structures, positive against each of the antibodies, were also observed. Numerous round, granular particles of 3–47 μm in diameter with one nucleus were distributed around pneumostome and/or inside the mantle. The cells surrounding the pneumostome area, located 10 μm beneath the surface, tended to have smaller cell soma ranging from 3 to 25 μm in diameter, while cells located in other areas were distributed uniformly inside the mantle, with a larger diameter ranging from 12 to 47 μm. The histological examination using back-filing Lucifer Yellow staining of the right parietal nerve with the three dermal photoreceptor antibodies confirmed that these overlapping-stained structures were dermal photoreceptors in Lymnaea. PMID:27493502

  7. Physiological characteristics of elite dancers of different dance styles.

    PubMed

    Liiv, Helena; Jürimäe, Toivo; Mäestu, Jarek; Purge, Priit; Hannus, Aave; Jürimäe, Jaak

    2014-01-01

    The present investigation was aimed to study international level dancesport dancer's aerobic capacity during incremental test and competition simulation in relation to the gender, dance style and international ranking. A total of 30 couples (12 Standard, 7 Latin American and 11 Ten Dance; aged 22.8 ± 6.6 years male and 22.0 ± 6.4 years female) performed an incremental treadmill test and competition simulation. In this study for the first time we carried out longer than one round competition simulation and compared three different dancesport styles (Standard, Latin American and Ten Dance). The results showed that dancers of these three dance styles had similar aerobic capacity values. The average maximal oxygen consumption (VO2max) values were 59.6 ± 5.1 and 51.2 ± 6.2 ml · min(-1) · kg(-1) for male and female dancers, respectively. Competition simulation showed that Latin American Dance discipline is physiologically more intensive compared to Standard and Ten Dance styles especially for the female dancers. It appeared that male and female Standard dancers tended to perform at lower intensity than anaerobic threshold (AT) during competition simulation (male 97.3 ± 2.9%; female 97.9 ± 3.6%), while Latin (male 101.4 ± 2.9%; female 106.7 ± 5.9%) and Ten Dance (male 100.7 ± 6.4%; female 99.2 ± 5.6%) competition intensity was higher compared to AT level of athletes. The highest heart rate during competition simulation was always found during the last dances (Paso Double, Jive or Quickstep) and in the last round of each dance style. No significant relationship between VO2max values and international rankings was registered.

  8. Water consumption and water-saving characteristics of a ground cover rice production system

    NASA Astrophysics Data System (ADS)

    Jin, Xinxin; Zuo, Qiang; Ma, Wenwen; Li, Sen; Shi, Jianchu; Tao, Yueyue; Zhang, Yanan; Liu, Yang; Liu, Xiaofei; Lin, Shan; Ben-Gal, Alon

    2016-09-01

    The ground cover rice production system (GCRPS) offers a potentially water-saving alternative to the traditional paddy rice production system (TPRPS) by furrow irrigating mulched soil beds and maintaining soils under predominately unsaturated conditions. The guiding hypothesis of this study was that a GCRPS would decrease both physiological and non-physiological water consumption of rice compared to a TPRPS while either maintaining or enhancing production. This was tested in a two-year field experiment with three treatments (TPRPS, GCRPSsat keeping root zone average soil water content near saturated, and GCRPS80% keeping root zone average soil water content as 80-100% of field water capacity) and a greenhouse experiment with four treatments (TPRPS, GCRPSsat, GCRPSfwc keeping root zone average soil water content close to field water capacity, and GCRPS80%). The water-saving characteristics of GCRPS were analyzed as a function of the measured soil water conditions, plant parameters regarding growth and production, and water input and consumption. In the field experiment, significant reduction in both physiological and non-physiological water consumption under GCRPS lead to savings in irrigation water of ∼61-84% and reduction in total input water of ∼35-47%. Compared to TPRPS, deep drainage was reduced ∼72-88%, evaporation was lessened ∼83-89% and transpiration was limited ∼6-10% under GCRPS. In addition to saving water, plant growth and grain yield were enhanced under GCRPS due to increased soil temperature in the root zone. Therefore, water use efficiencies (WUEs), based on transpiration, irrigation and total input water, were respectively improved as much as 27%, 609% and 110% under GCRPS. Increased yield attributed to up to ∼19%, decreased deep drainage accounted for ∼75%, decreased evaporation accounted for ∼14% and reduced transpiration for ∼5% of the enhancement in WUE of input water under GCRPS, while increased runoff and water storage had

  9. Seasonal variations and aeration effects on water quality improvements and physiological responses of Nymphaea tetragona Georgi.

    PubMed

    Lu, Xiao-Ming; Lu, Peng-Zhen; Huang, Min-Sheng; Dai, Ling-Peng

    2013-01-01

    Seasonal variations and aeration effects on water quality improvements and the physiological responses of Nymphaea tetragona Georgi were investigated with mesocosm experiments. Plants were hydroponically cultivated in six purifying tanks (aerated, non-aerated) and the characteristics of the plants were measured. Water quality improvements in purifying tanks were evaluated by comparing to the control tanks. The results showed that continuous aeration affected the plant morphology and physiology. The lengths of the roots, petioles and leaf limbs in aeration conditions were shorter than in non-aeration conditions. Chlorophyll and soluble protein contents of the leaf limbs in aerated tanks decreased, while peroxidase and catalase activities of roots tissues increased. In spring and summer, effects of aeration on the plants were less than in autumn. Total nitrogen (TN) and ammonia nitrogen (NH4(+)-N) in aerated tanks were lower than in non-aerated tanks, while total phosphorus (TP) and dissolved phosphorus (DP) increased in spring and summer. In autumn, effects of aeration on the plants became more significant. TN, NH4(+)-N, TP and DP became higher in aerated tanks than in non-aerated tanks in autumn. This work provided evidences for regulating aeration techniques based on seasonal variations of the plant physiology in restoring polluted stagnant water.

  10. Seasonal variations and aeration effects on water quality improvements and physiological responses of Nymphaea tetragona Georgi.

    PubMed

    Lu, Xiao-Ming; Lu, Peng-Zhen; Huang, Min-Sheng; Dai, Ling-Peng

    2013-01-01

    Seasonal variations and aeration effects on water quality improvements and the physiological responses of Nymphaea tetragona Georgi were investigated with mesocosm experiments. Plants were hydroponically cultivated in six purifying tanks (aerated, non-aerated) and the characteristics of the plants were measured. Water quality improvements in purifying tanks were evaluated by comparing to the control tanks. The results showed that continuous aeration affected the plant morphology and physiology. The lengths of the roots, petioles and leaf limbs in aeration conditions were shorter than in non-aeration conditions. Chlorophyll and soluble protein contents of the leaf limbs in aerated tanks decreased, while peroxidase and catalase activities of roots tissues increased. In spring and summer, effects of aeration on the plants were less than in autumn. Total nitrogen (TN) and ammonia nitrogen (NH4(+)-N) in aerated tanks were lower than in non-aerated tanks, while total phosphorus (TP) and dissolved phosphorus (DP) increased in spring and summer. In autumn, effects of aeration on the plants became more significant. TN, NH4(+)-N, TP and DP became higher in aerated tanks than in non-aerated tanks in autumn. This work provided evidences for regulating aeration techniques based on seasonal variations of the plant physiology in restoring polluted stagnant water. PMID:23819294

  11. Physiological evidence that pyramidal neurons lack functional water channels.

    PubMed

    Andrew, R David; Labron, Mark W; Boehnke, Susan E; Carnduff, Lisa; Kirov, Sergei A

    2007-04-01

    The physiological conditions that swell mammalian neurons are clinically important but contentious. Distinguishing the neuronal component of brain swelling requires viewing intact neuronal cell bodies, dendrites, and axons and measuring their changing volume in real time. Cultured or dissociated neuronal somata swell within minutes under acutely overhydrated conditions and shrink when strongly dehydrated. But paradoxically, most central nervous system (CNS) neurons do not express aquaporins, the membrane channels that conduct osmotically driven water. Using 2-photon laser scanning microscopy (2PLSM), we monitored neuronal volume under osmotic stress in real time. Specifically, the volume of pyramidal neurons in cerebral cortex and axon terminals comprising cerebellar mossy fibers was measured deep within live brain slices. The expected swelling or shrinking of the gray matter was confirmed by recording altered light transmittance and by indirectly measuring extracellular resistance over a wide osmotic range of -80 to +80 milliOsmoles (mOsm). Neurons expressing green fluorescent protein were then imaged with 2PLSM between -40 and +80 mOsm over 20 min. Surprisingly, pyramidal somata, dendrites, and spines steadfastly maintained their volume, as did the cerebellar axon terminals. This precluded a need for the neurons to acutely regulate volume, preserved their intrinsic electrophysiological stability, and confirmed that these CNS nerve cells lack functional aquaporins. Thus, whereas water easily permeates the aquaporin-rich endothelia and glia driving osmotic brain swelling, neurons tenatiously maintain their volume. However, these same neurons then swell dramatically upon oxygen/glucose deprivation or [K+]0 elevation, so prolonged depolarization (as during stroke or seizure) apparently swells neurons by opening nonaquaporin channels to water. PMID:16723408

  12. Behaviour during elevated water temperatures: can physiology explain movement of juvenile Atlantic salmon to cool water?

    PubMed

    Breau, Cindy; Cunjak, Richard A; Peake, Stephan J

    2011-07-01

    1. Temperature governs most physiological processes in animals. Ectotherms behaviourally thermoregulate by selecting habitats with temperatures regulating their body temperature for optimal physiological functioning. However, ectotherms can experience temperature extremes forcing the organisms to seek temperature refuge. 2. Fish actively avoid potentially lethal temperatures by moving to cool-water sites created by inflowing tributaries and groundwater seeps. Juvenile Atlantic salmon (Salmo salar) of different age classes exhibit different behavioural responses to elevated temperatures (>23 °C). Yearling (1+) and 2-year-old (2+) Atlantic salmon often cease feeding, abandon territorial behaviour and swim continuously in aggregations in cool-water sites; whereas young-of-the-year (0+) fish continue defending territories and foraging. 3. This study determined whether the behavioural shift in older individuals (2+) occurred when basal metabolic rate, driven by increasing water temperature, reached the maximum metabolic rate such that anaerobic pathways were recruited to provide energy to support vital processes. Behaviour (feeding and stress responses), oxygen consumption, muscle lactate and glycogen, and circulating blood lactate and glucose concentrations were measured in wild 0+ and 2+ Atlantic salmon acclimated to water temperatures between 16 and 28 °C. 4. Results indicate that oxygen consumption of the 2+ fish increased with temperature and reached a plateau at 24 °C, a temperature that corresponded to cessation of feeding and a significant increase in muscle and blood lactate levels. By contrast, oxygen consumption in 0+ fish did not reach a plateau, feeding continued and muscle lactate did not increase, even at the highest temperatures tested (28 °C). 5. To conclude, the experiment demonstrated that the 0+ and 2+ fish had different physiological responses to the elevated water temperatures. The results suggest that wild 2+ Atlantic salmon employ behavioural

  13. Root physiological and morphological characteristics of 24 rice varieties selected for diverse grain mineral

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To accumulate a mineral in the grain, a plant must first absorb that mineral from the soil. Root physiological characteristics, such as exudation of organic acids or oxygen, impact the availability, solubility and mobility of minerals in the soil, ultimately impacting the amount of minerals absorbe...

  14. Biological and physiological characteristics of Neotyphodium gansuense symbiotic with Achnatherum inebrians.

    PubMed

    Li, Chunjie; Nan, Zhibiao; Li, Fei

    2008-01-01

    Biological and physiological characteristics of Neotyphodium gansuense were compared with Neotyphodium coenophialum and Epichloë festucae at a range of temperatures and pH values, and on carbon and nitrogen amended media. N. gansuense was able to grow at 10-30 degrees C, but not at 5 degrees C, and slowly at 35 degrees C. The optimal temperature for both N. gansuense and N. coenophialum was 25 degrees C, but that of E. festucae was 20-25 degrees C. The optimal pH ranges for mycelial growth of N. gansuense, N. coenophialum and E. festucae were 5-9, 5-9 and 5-7, respectively. The Neotyphodium and Epichloë endophytes varied in their ability to grow on media containing different carbon and nitrogen nutrients. The preference of N. gansuense for carbon source was sucrose>glucose, lactose, sorbitol, inulin, maltose, mannitol, starch, fructose>xylose. Growth of all three endophytes tested was significantly improved by peptone, tryptone, casein, yeast extract and l-proline. Yeast extract, peptone, casein, tryptone, l-proline, potassium nitrate, ammonium oxalic acid and l-leucine significantly improved growth of N. gansuense. However, ammonium nitrite was not utilized at all by any tested endophyte. N. gansuense grew significantly better on potato dextrose agar (PDA) and oat meal agar (OMA) than on corn meal agar (CMA) and drunken-horse-grass agar (DA), and most slowly on water agar (WA) and saltwater nutrient agar (SNA).

  15. Anthropometric, physiological and maturational characteristics in selected elite and non-elite male adolescent basketball players.

    PubMed

    Torres-Unda, Jon; Zarrazquin, Idoia; Gil, Javier; Ruiz, Fátima; Irazusta, Amaia; Kortajarena, Maider; Seco, Jesus; Irazusta, Jon

    2013-01-01

    We investigated the anthropometric, physiological and maturation characteristics of young players (13-14 years old) associated with being successful in basketball. Body parameters were measured (stature, total body mass, skinfolds and lengths) and physiological capacities were assessed by endurance, sprint (20 m), jump and dribbling tests. Chronological age (CA) was recorded and maturity estimated using predicted age at peak height velocity (APHV). Anthropometric analysis indicated that elite players were taller, heavier and had a higher percentage of muscle. Further, physiological testing showed that these elite players perform better in jump, endurance, speed and agility tests (especially in the agility and ball tests). In addition, these skills are correlated with point average during the regular season. More basketball players born in the first semester of the year are selected and there is a predominance of early-maturing boys among those selected for the elite team. Those who are more mature have advantages in anthropometric characteristics and physiological test results. In conclusion, around puberty, physical and physiological parameters associated with maturity and CA are important in determining the success of basketball players. These findings should be taken into account by trainers and coaches, to avoid artificial bias in their selection choices.

  16. Influence of Morphological Characteristics on Physical and Physiological Performances of Tunisian Elite Male Handball Players

    PubMed Central

    Moncef, Cherif; Said, Mohamed; Olfa, Najlaoui; Dagbaji, Gomri

    2012-01-01

    Purpose The purpose of this study was to describe the body structure and morphological characteristics of Tunisian elite handball players, and to determine the effect of these variables on functional and physical performance levels. Methods A sample of 42 male handball players (mean age 21.98±3.24 years; training duration 12 years) at international level was submitted to a test battery comprising morphological, physical and physiological assessments. Tests were yo-yo intermittent recovery test, squat jump test, countermovement jump test, vertical-jump test, and Repeated sprint Ability. Measures for assessment of anthropometric characteristics were age, size, weight, body mass index, body fat, fat mass and thin mass. Results Weight was negatively correlated to the squat jump and the countermovement jump performance. Age, weight, and body composition measures (fat and thin body mass) were additionally negatively related to the maximal oxygen uptake, and to the maximal velocity obtained in the Yo-Yo recovery test. No relationship was found between size, body mass index, body fat and the physical abilities considered. Concerning the effects of physical characteristics on the functional performances, we can note a positive relationship between squat jump, countermovement jump, and the yo-yo recovery test performance. No relationship was found between vertical jump, repeated sprint ability, and the physiological performances. Conclusions Study results point to the existence of strong correlation between morphological and physical characteristics with functional characteristics. In handball, it is possible to have a reliable estimate of anthropometric measurements, physical and physiological performances. PMID:22942992

  17. Meta-analysis of digital game and study characteristics eliciting physiological stress responses.

    PubMed

    van der Vijgh, Benny; Beun, Robbert-Jan; Van Rood, Maarten; Werkhoven, Peter

    2015-08-01

    Digital games have been used as stressors in a range of disciplines for decades. Nonetheless, the underlying characteristics of these stressors and the study in which the stressor was applied are generally not recognized for their moderating effect on the measured physiological stress responses. We have therefore conducted a meta-analysis that analyzes the effects of characteristics of digital game stressors and study design on heart rate, systolic and diastolic blood pressure, in studies carried out from 1976 to 2012. In order to assess the differing quality between study designs, a new scale is developed and presented, coined reliability of effect size. The results show specific and consistent moderating functions of both game and study characteristics, on average accounting for around 43%, and in certain cases up to 57% of the variance found in physiological stress responses. Possible cognitive and physiological processes underlying these moderating functions are discussed, and a new model integrating these processes with the moderating functions is presented. These findings indicate that a digital game stressor does not act as a stressor by virtue of being a game, but rather derives its stressor function from its characteristics and the methodology in which it is used. This finding, together with the size of the associated moderations, indicates the need for a standardization of digital game stressors.

  18. Linkage of within vineyard soil properties, grapevine physiology, grape composition and sensory characteristics in a premium wine grape vineyard.

    NASA Astrophysics Data System (ADS)

    Smart, David; Hess, Sallie; Ebeler, Susan; Heymann, Hildegarde; Plant, Richard

    2014-05-01

    Analysis of numerous vineyards has revealed a very high degree of variation exists at the within vineyard scale and may outweigh in some cases broader mesoclimatic and geological factors. For this reason, selective harvest of high quality wine grapes is often conducted and based on subjective field sensory analysis (taste). This is an established practice in many wine growing regions. But the relationships between these subjective judgments to principle soil and grapevine physiological characteristics are not well understood. To move toward greater understanding of the physiological factors related to field sensory evaluation, physiological data was collected over the 2007 and 2008 growing seasons in a selectively harvested premium production Napa Valley estate vineyard, with a history of selective harvesting based on field sensory evaluation. Data vines were established and remained as individual study units throughout the data gathering and analysis phase, and geographic information systems science (GIS) was used to geographically scale physiological and other data at the vineyard level. Areas yielding grapes with perceived higher quality (subjective analysis) were characterized by vines with 1) statistically significantly lower (P < 0.05) leaf water potential (LWP) both pre-dawn (PD) and midday (MD), 2) smaller berry diameter and weight, 3) lower pruning weights, and 4) higher soluble solids (Brix). Strong positive correlations emerged between June ψPD and pre-harvest grape berry diameter (R2 = 0.616 in 2007 and 0.413 in 2008) and similar strong correlations existed for berry weight (R2 = 0.626 in 2007 and 0.554 in 2008). A trained sensory panel performed a sensory analysis and characterized fruit using and a multivariate, principal components, analysis (PCA). This approach indicated that grapes from vines with lowest midday leaf water potential at veraison (< -1.5 MPa) had sweeter and softer pulp, absence of vegetal characteristics, and browner and crunchier

  19. [Effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash].

    PubMed

    Du, She-ni; Bai, Gang-shuan; Liang, Yin-li

    2011-04-01

    A pot experiment with artificial shading was conducted to study the effects of soil moisture content and light intensity on the plant growth and leaf physiological characteristics of squash variety "Jingyingyihao". Under all test soil moisture conditions, 30% shading promoted the growth of "Jingyingyihao", with the highest yield at 70% - 80% soil relative moisture contents. 70% shading inhibited plant growth severely, only flowering and not bearing fruits, no economic yield produced. In all treatments, there was a similar water consumption trend, i. e., both the daily and the total water consumption decreased with increasing shading and decreasing soil moisture content. Among all treatments, 30% shading and 70% - 80% soil relative moisture contents had the highest water use efficiency (2.36 kg mm(-1) hm(-2)) and water output rate (1.57 kg mm(-1) hm(-2)). The net photosynthetic rate, transpiration rate, stomatal conductance, and chlorophyll content of squash leaves decreased with increasing shading, whereas the intercellular CO2 concentration was in adverse. The leaf protective enzyme activity and proline content decreased with increasing shading, and the leaf MAD content decreased in the order of 70% shading, natural radiation, and 30% shading. Under the three light intensities, the change characteristics of squash leaf photosynthesis, protective enzyme activity, and proline and MAD contents differed with the increase of soil relative moisture content.

  20. Landscape and plant physiological controls on water dynamics within a watershed

    NASA Astrophysics Data System (ADS)

    Hu, J.; Looker, N. T.; Martin, J. T.; Hoylman, Z. H.; Jencso, K. G.

    2014-12-01

    Across the Western U.S., declining snowpacks have resulted in increased water limitation, leading to reduced productivity in high elevation forests. While our current understanding of how forests respond to climate change is typically focused on measuring/modeling the physiological responses and climate feedbacks, our study aims to combine physiology with hydrology to examine how landscape topography modulates the sensitivity of forests to climate. In a forested watershed in Western Montana, we linked climate variability to the physical watershed characteristics and the physiological response of vegetation to examine forest transpiration and productivity rates. Across the entire watershed, we found a strong relationship between productivity and the topographic wetness index, a proxy for soil moisture storage. However, this relationship was highly dependent on the intensity of solar radiation, suggesting that at high elevations productivity was limited by temperature, while at low elevations productivity was limited by moisture. In order to identify the mechanisms responsible for this relationship, we then examined how different coniferous species respond to changing environmental and hydrologic regimes. We first examined transpiration and productivity rates at the hillslope scale at four plots, ranging in elevation and aspect across the watershed. We found trees growing in the hollows had higher transpiration and productivity rates than trees growing in the side slope, but that these differences were more pronounced at lower elevations. We then used oxygen isotope to examine water source use by different species across the watershed. We found that trees growing in the hollows used snowmelt for a longer period. This was most likely due to upslope subsidies of snowmelt water to the hollow areas. However, we found that trees growing at lower elevations used proportionally more snowmelt than trees at the higher elevations. This was most likely due to the trees at lower

  1. Landscape and plant physiological controls on water dynamics and forest productivity within a watershed

    NASA Astrophysics Data System (ADS)

    Hu, Jia; Jencso, Kelsey; Looker, Nathaniel; Martin, Justin; Hoylman, Zachary

    2015-04-01

    Across the Western U.S., declining snowpacks have resulted in increased water limitation, leading to reduced productivity in high elevation forests. While our current understanding of how forests respond to climate change is typically focused on measuring/modeling the physiological responses and climate feedbacks, our study aims to combine physiology with hydrology to examine how landscape topography modulates the sensitivity of forests to climate. In a forested watershed in Western Montana, we linked climate variability to the physical watershed characteristics and the physiological response of vegetation to examine forest transpiration and productivity rates. Across the entire watershed, we found a strong relationship between productivity and the topographic wetness index, a proxy for soil moisture storage. However, this relationship was highly dependent on the intensity of solar radiation, suggesting that at high elevations productivity was limited by temperature, while at low elevations productivity was limited by moisture. In order to identify the mechanisms responsible for this relationship, we then examined how different coniferous species respond to changing environmental and hydrologic regimes. We first examined transpiration and productivity rates at the hillslope scale at four plots, ranging in elevation and aspect across the watershed. We found trees growing in the hollows had higher transpiration and productivity rates than trees growing in the side slope, but that these differences were more pronounced at lower elevations. We then used oxygen isotope to examine water source use by different species across the watershed. We found that trees growing in the hollows used snowmelt for a longer period. This was most likely due to upslope subsidies of snowmelt water to the hollow areas. However, we found that trees growing at lower elevations used proportionally more snowmelt than trees at the higher elevations. This was most likely due to the trees at lower

  2. Morphological and physiological characteristics of transgenic cherry tomato mutant with HBsAg gene.

    PubMed

    Guan, Z J; Guo, B; Huo, Y L; Hao, H Y; Wei, Y H

    2011-08-01

    HBsAg gene was previously introduced into cherry tomato (Lycopersicum esculentum var. cerasiforme) by Agrobacterium-mediated transformation. To investigate the side effect of HBsAg gene in cherry tomato, we analyzed morphological and physiological characteristics of the transgenic mutant N244. The process was performed under field conditions. The results suggested that the mutant N244 exhibited morphological, cytological and physiological variation. First of all, compared with the wild plants NK, N244 had fleshy and dark green leaves, the fewer notches of leaf edge, more adventitious roots and barren seeds. Moreover, the chromosome of N244 were found to be triploid (n = 36) by flow cytometric analysis. Furthermore, N244 has obvious physiological alterations, as compared to NK. It was speculated that transformation of the genes probably led to ploidy variation, and further caused phenotype and physiological changes of plants. Our study will reveal side effects of the mutants, and promote cultivation of transgenic plants in the field. PMID:21954613

  3. Pharmacologic, physiologic, and psychological characteristics associated with emergence delirium in combat veterans.

    PubMed

    Wilson, John Tyler

    2014-10-01

    The goal of this research was to investigate, through active-duty Army anesthesia providers, their perceptions on emergence delirium (ED) in US combat veterans. Specifically, the pharmacologic, physiologic, and psychological characteristics associated with ED. An online survey was sent to all active-duty Army anesthesia providers with a response rate of 34%. Results indicated that the providers overwhelmingly agreed that ED was related to type of anesthetic used (67.1%) with potent inhalational agents and ketamine ranking highest (88.6% and 63.6%, respectively). Providers also overwhelmingly considered both physiologic and psychological factors (86.8% and 97.1%, respectively) as producing ED in combat veterans. Young age (57.5%) and traumatic brain injury (54.2%) were believed to be the most likely physiologic factors, with posttraumatic stress disorder (88%) and anxiety (84.8%) rated highest for psychological factors related to ED. This study emphasizes the need to develop a prospective clinical database involving all military anesthesia providers that could collect demographic, pharmacologic, psychological, and physiologic information on all combat veterans undergoing anesthesia. This kind of longitudinal data would provide answers to many of the unanswered questions that we currently have regarding combat veterans and ED. PMID:25842650

  4. [Effects of water stress and nitrogen fertilization on peanut root morphological development and leaf physiological activities].

    PubMed

    Ding, Hong; Zhang, Zhi-meng; Dai, Liang-xiang; Ci, Dun-wei; Qin, Fei-fei; Song, Wen-wu; Liu, Meng-juan; Fu, Xiao

    2015-02-01

    Taking 'Huayu 22' peanut as test material, effect of soil water content and nitrogen fertilization on the leaf physiological activities and root morphological characteristics of peanut plants were analyzed. Two levels of soil water condition were: (1) well-watered condition and (2) moderate water stress, and three levels of nitrogen were: (1) none nitrogen (N0), (2) moderate nitrogen (N1, 90 kg · hm(-2)) and (3) high nitrogen (N2, 180 kg · hm(-2)). The results showed that N1 significantly increased the peanut yield under two water conditions, but showed no significant effect on harvest index compared with N0. Under water stress condition, N1 had no significant effects on total root biomass and total root length, but the total root surface area was remarkably increased. The nitrogen fertilization significantly increased the root length and root surface area in 20-40 cm soil layer, and N2 significantly increased the root biomass and root surface area in the soil layer below 40 cm. The application of nitrogen remarkably increased CAT and POD activities in leaf, while MDA content was decreased with the increase of nitrogen level. Under well-watered condition, the root biomass, root length and root surface area in the soil layer below 40 cm and total root surface area were significantly reduced by nitrogen application, however, only N1 could increase leaf protective enzyme activities. Correlation analysis showed that the root length in 20-40 cm soil layer and SOD, CAT, POD activities in leaf were highly significantly related with peanut yield. PMID:26094460

  5. [Effects of water stress and nitrogen fertilization on peanut root morphological development and leaf physiological activities].

    PubMed

    Ding, Hong; Zhang, Zhi-meng; Dai, Liang-xiang; Ci, Dun-wei; Qin, Fei-fei; Song, Wen-wu; Liu, Meng-juan; Fu, Xiao

    2015-02-01

    Taking 'Huayu 22' peanut as test material, effect of soil water content and nitrogen fertilization on the leaf physiological activities and root morphological characteristics of peanut plants were analyzed. Two levels of soil water condition were: (1) well-watered condition and (2) moderate water stress, and three levels of nitrogen were: (1) none nitrogen (N0), (2) moderate nitrogen (N1, 90 kg · hm(-2)) and (3) high nitrogen (N2, 180 kg · hm(-2)). The results showed that N1 significantly increased the peanut yield under two water conditions, but showed no significant effect on harvest index compared with N0. Under water stress condition, N1 had no significant effects on total root biomass and total root length, but the total root surface area was remarkably increased. The nitrogen fertilization significantly increased the root length and root surface area in 20-40 cm soil layer, and N2 significantly increased the root biomass and root surface area in the soil layer below 40 cm. The application of nitrogen remarkably increased CAT and POD activities in leaf, while MDA content was decreased with the increase of nitrogen level. Under well-watered condition, the root biomass, root length and root surface area in the soil layer below 40 cm and total root surface area were significantly reduced by nitrogen application, however, only N1 could increase leaf protective enzyme activities. Correlation analysis showed that the root length in 20-40 cm soil layer and SOD, CAT, POD activities in leaf were highly significantly related with peanut yield.

  6. Comparison of the physiological characteristics of transgenic insect-resistant cotton and conventional lines

    PubMed Central

    Li, Xiaogang; Ding, Changfeng; Wang, Xingxiang; Liu, Biao

    2015-01-01

    The introduction of transgenic insect-resistant cotton into agricultural ecosystems has raised concerns regarding its ecological effects. Many studies have been conducted to compare the differences in characteristics between transgenic cotton and conventional counterparts. However, few studies have focused on the different responses of transgenic cotton to stress conditions, especially to the challenges of pathogens. The aim of this work is to determine the extent of variation in physiological characteristics between transgenic insect-resistant cotton and the conventional counterpart infected by cotton soil-borne pathogens. The results showed that the difference in genetic backgrounds is the main factor responsible for the effects on biochemical characteristics of transgenic cotton when incubating with cotton Fusarium oxysporum. However, genetic modification had a significantly greater influence on the stomatal structure of transgenic cotton than the effects of cotton genotypes. Our results highlight that the differences in genetic background and/or genetic modifications may introduce variations in physiological characteristics and should be considered to explore the potential unexpected ecological effects of transgenic cotton. PMID:25737015

  7. Comparison of the physiological characteristics of transgenic insect-resistant cotton and conventional lines.

    PubMed

    Li, Xiaogang; Ding, Changfeng; Wang, Xingxiang; Liu, Biao

    2015-03-04

    The introduction of transgenic insect-resistant cotton into agricultural ecosystems has raised concerns regarding its ecological effects. Many studies have been conducted to compare the differences in characteristics between transgenic cotton and conventional counterparts. However, few studies have focused on the different responses of transgenic cotton to stress conditions, especially to the challenges of pathogens. The aim of this work is to determine the extent of variation in physiological characteristics between transgenic insect-resistant cotton and the conventional counterpart infected by cotton soil-borne pathogens. The results showed that the difference in genetic backgrounds is the main factor responsible for the effects on biochemical characteristics of transgenic cotton when incubating with cotton Fusarium oxysporum. However, genetic modification had a significantly greater influence on the stomatal structure of transgenic cotton than the effects of cotton genotypes. Our results highlight that the differences in genetic background and/or genetic modifications may introduce variations in physiological characteristics and should be considered to explore the potential unexpected ecological effects of transgenic cotton.

  8. Is fishing selective for physiological and energetic characteristics in migratory adult sockeye salmon?

    PubMed

    Cooke, Steven J; Donaldson, Michael R; Hinch, Scott G; Crossin, Glenn T; Patterson, David A; Hanson, Kyle C; English, Karl K; Shrimpton, J Mark; Farrell, Anthony P

    2009-08-01

    There is extensive evidence that fishing is often selective for specific phenotypic characteristics, and that selective harvest can thus result in genotypic change. To date, however, there are no studies that evaluate whether fishing is selective for certain physiological or energetic characteristics that may influence fish behaviour and thus vulnerability to capture. Here, adult sockeye salmon (Oncorhynchus nerka) were used as a model to test the null hypothesis that fishing is not selective for specific physiological or energetic traits. Fish were intercepted during their spawning migrations, implanted with a gastric radio transmitter, and biopsied (i.e., non-lethally sampled for blood, gill tissue and quantification of energetic status). In both 2003 and 2006, we tagged and biopsied 301 and 770 sockeye salmon, respectively, in the marine environment en route to their natal river system to spawn. In 2006 an additional 378 individuals were tagged and biopsied in freshwater. We found that 23 (7.6%) of the marine fish tagged in 2003, 78 (10.1%) of the marine fish tagged in 2006 and 57 (15.1%) of the freshwater fish tagged in 2006 were harvested by one of three fisheries sectors that operate in the coastal marine environment and the Fraser River (i.e. commercial, recreational or First Nations fisheries between the site of release and Hell's Gate in the Fraser River, approximately 250 km upriver and 465 km from the ocean tagging site). However, fisheries were not open continually or consistently in different locations and for different fisheries sectors necessitating a paired analytical approach. As such, for statistical analyses we paired individual fish that were harvested with another fish of the same genetic stock that was released on the same date and exhibited similar migration behaviour, except that they successfully evaded capture and reached natal spawning grounds. Using two-tailed Wilcoxon matched pairs signed-rank tests, we revealed that the physiological

  9. Genetic and physiological controls of growth under water deficit.

    PubMed

    Tardieu, François; Parent, Boris; Caldeira, Cecilio F; Welcker, Claude

    2014-04-01

    The sensitivity of expansive growth to water deficit has a large genetic variability, which is higher than that of photosynthesis. It is observed in several species, with some genotypes stopping growth in a relatively wet soil, whereas others continue growing until the lower limit of soil-available water. The responses of growth to soil water deficit and evaporative demand share an appreciable part of their genetic control through the colocation of quantitative trait loci as do the responses of the growth of different organs to water deficit. This result may be caused by common mechanisms of action discussed in this paper (particularly, plant hydraulic properties). We propose that expansive growth, putatively linked to hydraulic processes, determines the sink strength under water deficit, whereas photosynthesis determines source strength. These findings have large consequences for plant modeling under water deficit and for the design of breeding programs. PMID:24569846

  10. Ubiquity, diversity and physiological characteristics of Geodermatophilaceae in Shapotou National Desert Ecological Reserve

    PubMed Central

    Sun, Hong-Min; Zhang, Tao; Yu, Li-Yan; Sen, Keya; Zhang, Yu-Qin

    2015-01-01

    The goal of this study was to gain insight into the diversity of culturable actinobacteria in desert soil crusts and to determine the physiological characteristics of the predominant actinobacterial group in these crusts. Culture-dependent method was employed to obtain actinobacterial strains from desert soil samples collected from Shapotou National Desert Ecological Reserve (NDER) located in Tengger Desert, China. A total of 376 actinobacterial strains were isolated and 16S rRNA gene sequences analysis indicated that these isolates belonged to 29 genera within 18 families, among which the members of the family Geodermatophilaceae were predominant. The combination of 16S rRNA gene information and the phenotypic data allowed these newly-isolated Geodermatophilaceae members to be classified into 33 “species clusters,” 11 of which represented hitherto unrecognized species. Fermentation broths from 19.7% of the isolated strains showed activity in at least one of the six screens for antibiotic activity. These isolates exhibited bio-diversity in enzymatic characteristics and carbon utilization profiles. The physiological characteristics of the isolates from different types of crusts or bare sand samples were specific to their respective micro-ecological environments. Our study revealed that members of the family Geodermatophilaceae were ubiquitous, abundant, and diverse in Shapotou NDER, and these strains may represent a new major group of potential functional actinobacteria in desert soil. PMID:26483778

  11. Ubiquity, diversity and physiological characteristics of Geodermatophilaceae in Shapotou National Desert Ecological Reserve.

    PubMed

    Sun, Hong-Min; Zhang, Tao; Yu, Li-Yan; Sen, Keya; Zhang, Yu-Qin

    2015-01-01

    The goal of this study was to gain insight into the diversity of culturable actinobacteria in desert soil crusts and to determine the physiological characteristics of the predominant actinobacterial group in these crusts. Culture-dependent method was employed to obtain actinobacterial strains from desert soil samples collected from Shapotou National Desert Ecological Reserve (NDER) located in Tengger Desert, China. A total of 376 actinobacterial strains were isolated and 16S rRNA gene sequences analysis indicated that these isolates belonged to 29 genera within 18 families, among which the members of the family Geodermatophilaceae were predominant. The combination of 16S rRNA gene information and the phenotypic data allowed these newly-isolated Geodermatophilaceae members to be classified into 33 "species clusters," 11 of which represented hitherto unrecognized species. Fermentation broths from 19.7% of the isolated strains showed activity in at least one of the six screens for antibiotic activity. These isolates exhibited bio-diversity in enzymatic characteristics and carbon utilization profiles. The physiological characteristics of the isolates from different types of crusts or bare sand samples were specific to their respective micro-ecological environments. Our study revealed that members of the family Geodermatophilaceae were ubiquitous, abundant, and diverse in Shapotou NDER, and these strains may represent a new major group of potential functional actinobacteria in desert soil.

  12. Physical attributes, physiological characteristics, on-court performances and nutritional strategies of female and male basketball players.

    PubMed

    Ziv, Gal; Lidor, Ronnie

    2009-01-01

    This article reviews a series of studies (n = 51) examining physical attributes, physiological characteristics, on-court performances and nutritional strategies of female and male elite basketball players. These studies included relevant information on physical and physiological variables, such as height, weight, somatotype, relative size, aerobic profile, strength, anaerobic power, agility and speed. Six main findings emerged from our review: (i) differences in physical attributes exist among playing positions and skill levels (e.g. guards tend to be lighter, shorter and more mesomorphic than centres); (ii) maximum aerobic capacity (VO(2max)) values of female and male players are 44.0-54.0 and 50-60 mLO(2)/kg/min, respectively; (iii) male and female players of higher skill levels tend to have higher vertical jump values; (iv) the more skilled female and male players are faster and more agile than the less skilled players; (v) guards tend to perform more high-intensity movements during game play compared with forwards and centres; and (vi) a water deficit of 2% of bodyweight can lead to reduced physical and mental performance during an actual game. Five limitations associated with the testing protocols used in the studies are outlined, among them the lack of a longitudinal approach, lack of tests performed under physical exertion conditions, and lack of studies using a time-motion analysis. In addition, three practical recommendations for the basketball coach and the strength and conditioning coach are presented. It is concluded that the data emerging from these studies, combined with the knowledge already obtained from the studies on physical and physiological characteristics of elite basketball players, should be applied by basketball and strength and conditioning coaches when planning training programmes for elite basketball players. PMID:19530751

  13. Physical attributes, physiological characteristics, on-court performances and nutritional strategies of female and male basketball players.

    PubMed

    Ziv, Gal; Lidor, Ronnie

    2009-01-01

    This article reviews a series of studies (n = 51) examining physical attributes, physiological characteristics, on-court performances and nutritional strategies of female and male elite basketball players. These studies included relevant information on physical and physiological variables, such as height, weight, somatotype, relative size, aerobic profile, strength, anaerobic power, agility and speed. Six main findings emerged from our review: (i) differences in physical attributes exist among playing positions and skill levels (e.g. guards tend to be lighter, shorter and more mesomorphic than centres); (ii) maximum aerobic capacity (VO(2max)) values of female and male players are 44.0-54.0 and 50-60 mLO(2)/kg/min, respectively; (iii) male and female players of higher skill levels tend to have higher vertical jump values; (iv) the more skilled female and male players are faster and more agile than the less skilled players; (v) guards tend to perform more high-intensity movements during game play compared with forwards and centres; and (vi) a water deficit of 2% of bodyweight can lead to reduced physical and mental performance during an actual game. Five limitations associated with the testing protocols used in the studies are outlined, among them the lack of a longitudinal approach, lack of tests performed under physical exertion conditions, and lack of studies using a time-motion analysis. In addition, three practical recommendations for the basketball coach and the strength and conditioning coach are presented. It is concluded that the data emerging from these studies, combined with the knowledge already obtained from the studies on physical and physiological characteristics of elite basketball players, should be applied by basketball and strength and conditioning coaches when planning training programmes for elite basketball players.

  14. Physiological responses and characteristics of table tennis matches determined in official tournaments.

    PubMed

    Zagatto, Alessandro M; Morel, Erika A; Gobatto, Claudio A

    2010-04-01

    The purpose of this study was to verify the physiological responses and the match characteristics of table tennis and also to compare these responses in 2 different performance-level athletes from official tournaments. Twenty male table tennis players (12 regional experience-RP and 8 national and international experience-NP) were participants in the study. Blood lactate concentration ([LAC]) and heart rate (HR) were measured as physiological parameters in 21 official table tennis matches, and other 12 matches had recorded the duration of rally (DR), rest time, effort and rest ratio (E:R), total playing time (TPT), effective playing time (EPT), and frequency of shots by video analyses. The [LAC] verified in all matches was 1.8 mmol.L (+/-0.8), whereas the [LAC] peak was 2.2 mmol.L (+/-0.8). There were no significant differences between the 2 groups (p > 0.05) in both parameters. The HR was 164 b.min (+/-14), corresponding to 81.2% (+/-7.4) of the predicted maximum HR. As characteristics of the matches, the DR corresponded to 3.4 seconds (+/-1.7), rest time to 8.1 seconds (+/-5.1), E:R to 0.4 (+/-0.2), TPT to 970.5 seconds (+/-336.1), EPT to 44.3% (+/-23.7), and frequency of shots to 35.3 balls.min (+/-7.7). Among groups, the rest time was lower in RP than in NP. Consistently, the E:R and EPT were higher in RP than in NP (p < 0.05). The results suggest that table tennis matches present the aerobic system as a principal output energy, the phosphagenic system being the most important during efforts. The information pertaining to the physiological profile and the characteristics of table tennis should be used by coaches planning physical training and specific exercise prescriptions aiming at achieving maximal sport performance. PMID:20300034

  15. Physiological responses and characteristics of table tennis matches determined in official tournaments.

    PubMed

    Zagatto, Alessandro M; Morel, Erika A; Gobatto, Claudio A

    2010-04-01

    The purpose of this study was to verify the physiological responses and the match characteristics of table tennis and also to compare these responses in 2 different performance-level athletes from official tournaments. Twenty male table tennis players (12 regional experience-RP and 8 national and international experience-NP) were participants in the study. Blood lactate concentration ([LAC]) and heart rate (HR) were measured as physiological parameters in 21 official table tennis matches, and other 12 matches had recorded the duration of rally (DR), rest time, effort and rest ratio (E:R), total playing time (TPT), effective playing time (EPT), and frequency of shots by video analyses. The [LAC] verified in all matches was 1.8 mmol.L (+/-0.8), whereas the [LAC] peak was 2.2 mmol.L (+/-0.8). There were no significant differences between the 2 groups (p > 0.05) in both parameters. The HR was 164 b.min (+/-14), corresponding to 81.2% (+/-7.4) of the predicted maximum HR. As characteristics of the matches, the DR corresponded to 3.4 seconds (+/-1.7), rest time to 8.1 seconds (+/-5.1), E:R to 0.4 (+/-0.2), TPT to 970.5 seconds (+/-336.1), EPT to 44.3% (+/-23.7), and frequency of shots to 35.3 balls.min (+/-7.7). Among groups, the rest time was lower in RP than in NP. Consistently, the E:R and EPT were higher in RP than in NP (p < 0.05). The results suggest that table tennis matches present the aerobic system as a principal output energy, the phosphagenic system being the most important during efforts. The information pertaining to the physiological profile and the characteristics of table tennis should be used by coaches planning physical training and specific exercise prescriptions aiming at achieving maximal sport performance.

  16. AFM Structural Characterization of Drinking Water Biofilm under Physiological Conditions

    EPA Science Inventory

    Due to the complexity of mixed culture drinking water biofilm, direct visual observation under in situ conditions has been challenging. In this study, atomic force microscopy (AFM) revealed the three dimensional morphology and arrangement of drinking water relevant biofilm in air...

  17. Some blood parameters of water buffalo in different physiological conditions.

    PubMed

    Pizzuti, G P; Salvatori, G C

    1993-10-01

    The Authors have studied the changes of GOT, GPT, ALP, CPK and Se in buffaloes under different physiological conditions (age, diet, different pre and post partum times). 99 adult buffaloes were classified in 8 groups on the basis of different pre, post partum time intervals. Moreover, other 39 animals were divided into 4 groups: A = 60-90 day old animals, fed with reconstituted milk supplemented with Vit E; B = same age, fed with maternal milk; C = 6-8 month old animals; D = 12-18 month old animals. In the various classes of animals blood ALP, GPT, GOT, CPK and Se were monitored. Results showed that the high variability in blood activity of the studied enzymes suggest that in establishing their reference values the physiological condition of the subject and the time interval from the parturition must be taken into account. The fact that Se was not detectable in many pregnant animals suggests that the prevention of myodistrophy in buffalo calves must be effected in prenatal epoch.

  18. Cold Water Fatalities: An Overview of Physiological Responses.

    ERIC Educational Resources Information Center

    Bernhartsen, J. C.; Schlenker, Richard

    1981-01-01

    Cold water fatalities are described and defined, including drownings, trauma, hydrocution and hypothermia. The levels of hypothermia are outlined, and symptoms and steps to stop and reverse hypothermia are described. (DS)

  19. Water uptake in barley grain: Physiology; genetics and industrial applications.

    PubMed

    Cu, Suong; Collins, Helen M; Betts, Natalie S; March, Timothy J; Janusz, Agnieszka; Stewart, Doug C; Skadhauge, Birgitte; Eglinton, Jason; Kyriacou, Bianca; Little, Alan; Burton, Rachel A; Fincher, Geoffrey B

    2016-01-01

    Water uptake by mature barley grains initiates germination and is the first stage in the malting process. Here we have investigated the effects of starchy endosperm cell wall thickness on water uptake, together with the effects of varying amounts of the wall polysaccharide, (1,3;1,4)-β-glucan. In the latter case, we examined mutant barley lines from a mutant library and transgenic barley lines in which the (1,3;1,4)-β-glucan synthase gene, HvCslF6, was down-regulated by RNA interference. Neither cell wall thickness nor the levels of grain (1,3;1,4)-β-glucan were significantly correlated with water uptake but are likely to influence modification during malting. However, when a barley mapping population was phenotyped for rate of water uptake into grain, quantitative trait locus (QTL) analysis identified specific regions of chromosomes 4H, 5H and 7H that accounted for approximately 17%, 18% and 11%, respectively, of the phenotypic variation. These data indicate that variation in water uptake rates by elite malting cultivars of barley is genetically controlled and a number of candidate genes that might control the trait were identified under the QTL. The genomics data raise the possibility that the genetic variation in water uptake rates might be exploited by breeders for the benefit of the malting and brewing industries. PMID:26566843

  20. Effects of age on the physiological and mechanical characteristics of human femoropopliteal arteries.

    PubMed

    Kamenskiy, Alexey V; Pipinos, Iraklis I; Dzenis, Yuris A; Phillips, Nicholas Y; Desyatova, Anastasia S; Kitson, Justin; Bowen, Robert; MacTaggart, Jason N

    2015-01-01

    Surgical and interventional therapies for peripheral artery disease (PAD) are notorious for high rates of failure. Interactions between the artery and repair materials play an important role, but comprehensive data describing the physiological and mechanical characteristics of human femoropopliteal arteries are not available. Fresh femoropopliteal arteries were obtained from 70 human subjects (13-79 years old), and in situ vs. excised arterial lengths were measured. Circumferential and longitudinal opening angles were determined for proximal superficial femoral, proximal popliteal and distal popliteal arteries. Mechanical properties were assessed by multi-ratio planar biaxial extension, and experimental data were used to calculate physiological stresses and stretches, in situ axial force and anisotropy. Verhoeff-Van Gieson-stained axial and transverse arterial sections were used for histological analysis. Most specimens demonstrated nonlinear deformations and were more compliant longitudinally than circumferentially. In situ axial pre-stretch decreased 0.088 per decade of life. In situ axial force and axial stress also decreased with age, but circumferential physiological stress remained constant. Physiological circumferential stretch decreased 55-75% after 45 years of age. Histology demonstrated a thickened external elastic lamina with longitudinally oriented elastin that was denser in smaller, younger arteries. Axial elastin likely regulates axial pre-stretch to help accommodate the complex deformations required of the artery wall during locomotion. Degradation and fragmentation of elastin as a consequence of age, cyclic mechanical stress and atherosclerotic arterial disease may contribute to decreased in situ axial pre-stretch, predisposing to more severe kinking of the artery during limb flexion and loss of energy-efficient arterial function.

  1. Baseline Physiologic and Psychosocial Characteristics of Transgender Youth Seeking Care for Gender Dysphoria

    PubMed Central

    Olson, Johanna; Schrager, Sheree M.; Belzer, Marvin; Simons, Lisa K.; Clark, Leslie F.

    2016-01-01

    Purpose The purpose of this study was to describe baseline characteristics of participants in a prospective observational study of transgender youth (aged 12–24 years) seeking care for gender dysphoria at a large, urban transgender youth clinic. Methods Eligible participants presented consecutively for care at between February 2011 and June 2013 and completed a computer-assisted survey at their initial study visit. Physiologic data were abstracted from medical charts. Data were analyzed by descriptive statistics, with limited comparisons between transmasculine and transfeminine participants. Results A total of 101 youth were evaluated for physiologic parameters, 96 completed surveys assessing psychosocial parameters. About half (50.5%) of the youth were assigned a male sex at birth. Baseline physiologic values were within normal ranges for assigned sex at birth. Youth recognized gender incongruence at a mean age of 8.3 years (standard deviation = 4.5), yet disclosed to their family much later (mean = 17.1; standard deviation = 4.2). Gender dysphoria was high among all participants. Thirty-five percent of the participants reported depression symptoms in the clinical range. More than half of the youth reported having thought about suicide at least once in their lifetime, and nearly a third had made at least one attempt. Conclusions Baseline physiologic parameters were within normal ranges for assigned sex at birth. Transgender youth are aware of the incongruence between their internal gender identity and their assigned sex at early ages. Prevalence of depression and suicidality demonstrates that youth may benefit from timely and appropriate intervention. Evaluation of these youth over time will help determine the impact of medical intervention and mental health therapy. PMID:26208863

  2. [Effects of selenite addition on selenium absorption, root morphology and physiological characteristics of rape seedlings].

    PubMed

    Liu, Xin-wei; Wang, Qiao-lan; Duan, Bi-hui; Lin, Ya-meng; Zhao, Xiao-hu; Hu, Cheng-xiao; Zhao, Zhu-qing

    2015-07-01

    Abstract: The rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo solution cultivation at seedling stage to investigate the effects of selenite addition on the selenium (Se) absorption and distribution, root morphology and physiological characteristics of rape seedlings. The results showed that the bioaccumulation ability of Se decreased significantly with increasing the Se application rate, but the Se distribution coefficient remained around 0.9 with no significant influence. The application of 10 µmol . L-1 selenite stimulated the growth of rape seedlings through improving the root physiological characteristics and root morphology significantly, including significantly increasing the production of superoxide radical (O2∙-) rate and the activities of superoxide dismutase (SOD), peroxidase (POD) and fungal catalase (CAT) in the root system, which resulted in a reduction of the lipids peroxidation (MDA) content as much as 26.0%, consequently increasing the root activity as much as 17.4%. The promoting degrees of selenite on root morphological parameters were from strong to weak in such a tendency: root volume > total surface area > number of root forks > total root length > number of root tips > average diameter. However, such positive effects had no significant difference with those in treatment with 1 µmol . L-1 selenite, indicating that small amounts (≤ 10 Lmol . L-1) of selenite were able to increase the activity of antioxidant enzymes and reduce the content of MDA in root system, which could increase root activity and improve root morphology, hence increased the biomass of rape seedlings.

  3. The science of badminton: game characteristics, anthropometry, physiology, visual fitness and biomechanics.

    PubMed

    Phomsoupha, Michael; Laffaye, Guillaume

    2015-04-01

    Badminton is a racket sport for two or four people, with a temporal structure characterized by actions of short duration and high intensity. This sport has five events: men's and women's singles, men's and women's doubles, and mixed doubles, each requiring specific preparation in terms of technique, control and physical fitness. Badminton is one of the most popular sports in the world, with 200 million adherents. The decision to include badminton in the 1992 Olympics Game increased participation in the game. This review focuses on the game characteristics, anthropometry, physiology, visual attributes and biomechanics of badminton. Players are generally tall and lean, with an ectomesomorphic body type suited to the high physiological demands of a match. Indeed, a typical match characteristic is a rally time of 7 s and a resting time of 15 s, with an effective playing time of 31%. This sport is highly demanding, with an average heart rate (HR) of over 90% of the player's maximal HR. The intermittent actions during a game are demanding on both the aerobic and anaerobic systems: 60-70% on the aerobic system and approximately 30% on the anaerobic system, with greater demand on the alactic metabolism with respect to the lactic anaerobic metabolism. The shuttlecock has an atypical trajectory, and the players perform specific movements such as lunging and jumping, and powerful strokes using a specific pattern of movement. Lastly, badminton players are visually fit, picking up accurate visual information in a short time. Knowledge of badminton can help to improve coaching and badminton skills.

  4. Physiological characteristics of the anaerobic ammonium-oxidizing bacterium 'Candidatus Brocadia sinica'.

    PubMed

    Oshiki, Mamoru; Shimokawa, Masaki; Fujii, Naoki; Satoh, Hisashi; Okabe, Satoshi

    2011-06-01

    The present study investigated the phylogenetic affiliation and physiological characteristics of bacteria responsible for anaerobic ammonium oxidization (anammox); these bacteria were enriched in an anammox reactor with a nitrogen removal rate of 26.0 kg N m(-3) day(-1). The anammox bacteria were identified as representing 'Candidatus Brocadia sinica' on the basis of phylogenetic analysis of rRNA operon sequences. Physiological characteristics examined were growth rate, kinetics of ammonium oxidation and nitrite reduction, temperature, pH and inhibition of anammox. The maximum specific growth rate (μ(max)) was 0.0041 h(-1), corresponding to a doubling time of 7 days. The half-saturation constants (K(s)) for ammonium and nitrite of 'Ca. B. sinica' were 28±4 and 86±4 µM, respectively, higher than those of 'Candidatus Brocadia anammoxidans' and 'Candidatus Kuenenia stuttgartiensis'. The temperature and pH ranges of anammox activity were 25-45 °C and pH 6.5-8.8, respectively. Anammox activity was inhibited in the presence of nitrite (50 % inhibition at 16 mM), ethanol (91 % at 1 mM) and methanol (86 % at 1 mM). Anammox activities were 80 and 70 % of baseline in the presence of 20 mM phosphorus and 3 % salinity, respectively. The yield of biomass and dissolved organic carbon production in the culture supernatant were 0.062 and 0.005 mol C (mol NH (+)(-4))(-1), respectively. This study compared physiological differences between three anammox bacterial enrichment cultures to provide a better understanding of anammox niche specificity in natural and man-made ecosystems.

  5. A comparison of physiological and anthropometric characteristics among playing positions in junior rugby league players

    PubMed Central

    Gabbett, T

    2005-01-01

    Objectives: To compare the physiological and anthropometric characteristics of specific playing positions and positional playing groups in junior rugby league players. Methods: Two hundred and forty junior rugby league players underwent measurements of standard anthropometry (body mass, height, sum of four skinfolds), muscular power (vertical jump), speed (10, 20, and 40 m sprint), agility (L run), and estimated maximal aerobic power (multi-stage fitness test) during the competitive phase of the season, after players had obtained a degree of match fitness. Results: Props were significantly (p<0.05) taller, heavier, and had greater skinfold thickness than all other positions. The halfback and centre positions were faster than props over 40 m. Halfbacks had significantly (p<0.05) greater estimated maximal aerobic power than props. When data were analysed according to positional similarities, it was found that the props positional group had lower 20 and 40 m speed, agility, and estimated maximal aerobic power than the hookers and halves and outside backs positional groups. Differences in the physiological and anthropometric characteristics of other individual playing positions and positional playing groups were uncommon. Conclusions: The results of this study demonstrate that few physiological and anthropometric differences exist among individual playing positions in junior rugby league players, although props are taller, heavier, have greater skinfold thickness, lower 20 and 40 m speed, agility, and estimated maximal aerobic power than other positional playing groups. These findings provide normative data and realistic performance standards for junior rugby league players competing in specific individual positions and positional playing groups. PMID:16118309

  6. Water distribution characteristics of spray nozzles in a cooling tower

    NASA Astrophysics Data System (ADS)

    Vitkovic, Pavol

    2015-05-01

    Water distribution characteristics of spray nozzles with spray plates used to distribute cooling water to the cooling fills in a cooling tower is one of the important parameters for the selection of nozzles. Water distribution characteristic describes the distribution of water from the axis of the nozzle along a fill. One of the parameters affecting the water distribution characteristic of the nozzle is airflow velocity of counter flow airstream. Water distribution characteristics are commonly measured using by a set of containers. The problem with this method of the measurement of characteristics is block of the airflow with collections of containers. Therefore, this work is using the visualization method.

  7. Bioenergetics and thermal physiology of American water shrews (Sorex palustris).

    PubMed

    Gusztak, R W; Macarthur, R A; Campbell, K L

    2005-02-01

    Rates of O(2) consumption and CO(2) production, telemetered body temperature (T(b)) and activity level were recorded from adult and subadult water shrews (Sorex palustris) over an air temperature (T(a)) range of 3-32 degrees C. Digesta passage rate trials were conducted before metabolic testing to estimate the minimum fasting time required for water shrews to achieve a postabsorptive state. Of the 228 metabolic trials conducted on 15 water shrews, 146 (64%) were discarded because the criteria for inactivity were not met. Abdominal T(b) of S. palustris was independent of T(a) and averaged 38.64 +/- 0.07 degrees C. The thermoneutral zone extended from 21.2 degrees C to at least 32 degrees C. Our estimate of the basal metabolic rate for resting, postabsorptive water shrews (96.88 +/- 2.93 J g(-1) h(-1) or 4.84 +/- 0.14 ml O(2) g(-1) h(-1)) was three times the mass-predicted value, while their minimum thermal conductance in air (0.282 +/- 0.013 ml O(2) g(-1) h(-1)) concurred with allometric predictions. The mean digesta throughput time of water shrews fed mealworms (Tenebrio molitor) or ground meat was 50-55 min. The digestibility coefficients for metabolizable energy (ME) of water shrews fed stickleback minnows (Culaea inconstans) and dragonfly nymphs (Anax spp. and Libellula spp.) were 85.4 +/- 1.3% and 82.8 +/- 1.1%, respectively. The average metabolic rate (AMR) calculated from the gas exchange of six water shrews at 19-22 degrees C (208.0 +/- 17.0 J g(-1) h(-1)) was nearly identical to the estimate of energy intake (202.9 +/- 12.9 J g(-1) h(-1)) measured for these same animals during digestibility trials (20 degrees C). Based on 24-h activity trials and our derived ME coefficients, the minimum daily energy requirement of an adult (14.4 g) water shrew at T(a) = 20 degrees C is 54.0 kJ, or the energetic equivalent of 14.7 stickleback minnows.

  8. Bioenergetics and thermal physiology of American water shrews (Sorex palustris).

    PubMed

    Gusztak, R W; Macarthur, R A; Campbell, K L

    2005-02-01

    Rates of O(2) consumption and CO(2) production, telemetered body temperature (T(b)) and activity level were recorded from adult and subadult water shrews (Sorex palustris) over an air temperature (T(a)) range of 3-32 degrees C. Digesta passage rate trials were conducted before metabolic testing to estimate the minimum fasting time required for water shrews to achieve a postabsorptive state. Of the 228 metabolic trials conducted on 15 water shrews, 146 (64%) were discarded because the criteria for inactivity were not met. Abdominal T(b) of S. palustris was independent of T(a) and averaged 38.64 +/- 0.07 degrees C. The thermoneutral zone extended from 21.2 degrees C to at least 32 degrees C. Our estimate of the basal metabolic rate for resting, postabsorptive water shrews (96.88 +/- 2.93 J g(-1) h(-1) or 4.84 +/- 0.14 ml O(2) g(-1) h(-1)) was three times the mass-predicted value, while their minimum thermal conductance in air (0.282 +/- 0.013 ml O(2) g(-1) h(-1)) concurred with allometric predictions. The mean digesta throughput time of water shrews fed mealworms (Tenebrio molitor) or ground meat was 50-55 min. The digestibility coefficients for metabolizable energy (ME) of water shrews fed stickleback minnows (Culaea inconstans) and dragonfly nymphs (Anax spp. and Libellula spp.) were 85.4 +/- 1.3% and 82.8 +/- 1.1%, respectively. The average metabolic rate (AMR) calculated from the gas exchange of six water shrews at 19-22 degrees C (208.0 +/- 17.0 J g(-1) h(-1)) was nearly identical to the estimate of energy intake (202.9 +/- 12.9 J g(-1) h(-1)) measured for these same animals during digestibility trials (20 degrees C). Based on 24-h activity trials and our derived ME coefficients, the minimum daily energy requirement of an adult (14.4 g) water shrew at T(a) = 20 degrees C is 54.0 kJ, or the energetic equivalent of 14.7 stickleback minnows. PMID:15592850

  9. In situ Determination of Physiological States Under Conditions Characteristic of the Subseafloor Microbial Biosphere

    NASA Astrophysics Data System (ADS)

    Schrenk, M. O.

    2008-12-01

    Studies of water samples from the deep sea have revealed organisms specifically adapted to the low temperatures (~2° C) and elevated pressures (~100 MPa) native to these environments and elucidated genetic and physiological adaptations of life to high pressures. Investigation of the subsurface biosphere, at pressures exceeding those of the deep sea, has pushed the depth limits of microbial ecosystems to at least 1000 meters below the seafloor and 3-4 km into the continental lithosphere. In many of these environments, organisms are confronted with multiple stressors including not only high pressures, but high temperatures and low energy fluxes. Subsurface microorganisms live at a precarious boundary between geologically-supported growth and cell death and remineralization. As a result of these factors the calculated average growth rates of these organisms have challenged our notions of what is biologically possible. A limitation to our study of deep ecosystems has been an inability to accurately characterize microbial physiology under conditions found in subsurface habitats. This paper describes a strategy to distinguish the physiological status of microorganisms indigenous to the deep subseafloor at environmentally relevant temperatures (50 - 200° C) and pressures (30 - 300 MPa). Preliminary results using chemolithoautotrophic bacteria and hyperthermophilic Archaea show that four distinct physiological states (active and growing, active but non-growing, viable but inactive, and dead) can be distinguished in situ using biomolecular probes coupled to geochemical measurements. Further refinements of this approach can be used to expand our understanding of microbial adaptations to high pressure environments, and be linked to both genetic and geochemical studies at high pressure. The data produced by such experiments will be important to deciphering both the extent and the biogeochemical consequences of a deep subsurface biosphere.

  10. Physiological and anatomical characteristics of primary vestibular afferent neurons in the bullfrog.

    PubMed

    Honrubia, V; Sitko, S; Kimm, J; Betts, W; Schwartz, I

    1981-01-01

    Intracellular recordings were made in the VIIIth nerve of the bullfrog (Rana catesbiana) to measure the membrane characteristics and obtain records of spontaneous and evoked spike activity of primary semicircular canal afferents. Physiological stimulation of the canals was achieved by rotating the preparation on a servomotor driven turntable with the animals' head centered in the rotational axis. The responses of each neuron to sinusoidal rotations at frequencies of 0.05Hz, 0.5Hz and for impulsive accelerations of 400 deg/sec2 were obtained. Membrane characteristics measured included the cell resting and action potential amplitude, and spike-activation threshold for applied currents. Physiologically characterized neurons were injected with horseradish peroxidase by applying pneumatic pressure and/or iontophoretic currents to the micropipettes containing 5% HRP in 1 M KCI. Following survival times of 12--48 h, the VIIIth nerve and attached vestibular end organ was removed for histochemical processing using a diaminobenzidine procedure to visualize the HRP reaction product. Light microscopy was used to discern the anatomical features of the neurons and to trace their peripheral dendritic trajectories from the ganglion to their termination(s) in the crista. Our studies have revealed that the bullfrog's primary vestibular afferents are characterized by a broad range of soma and axon diameters which correspond to an equally broad range of spontaneous and evoked activity characteristics. The largest neurons had more irregular spontaneous firing rates and consistently exhibited the greatest gain and smallest phase shifts with respect to head acceleration. These neurons consistently terminated at or near the central region of the crista. On the other hand, the smallest neurons were characterized by having the most regular spontaneous discharge patterns, the lowest gains, and greatest phase shifts with respect to head acceleration. Our findings are thus consistent with the

  11. Behavioral and physiological characteristics of Indian and Chinese-Indian hybrid rhesus macaque infants.

    PubMed

    Champoux, M; Higley, J D; Suomi, S J

    1997-07-01

    Strain differences in temperament and physiology have been reported for several animal species, but nonhuman primates have not been well studied in this regard. We assessed behavioral and physiology in Chinese-Indian hybrid (n = 13) and Indian-origin (n = 29) nursery-reared rhesus monkey infants. Previous data indicate that Chinese-origin and Chinese-Indian hybrid rhesus exhibit more aggression directed toward humans and conspecifics and are more irritable in response to neonatal assessment procedures than are Indian-derived rhesus. In addition, in rhesus adults, low levels of cerebrospinal fluid 5-HIAA have been correlated with impulsivity, aggressive behavior, and diminished social competence. We therefore hypothesized that hybrid infants would exhibit more behavioral and adrenocortical reactivity in the home cage and during social separations, would be less sociable in their peer groups, and would exhibit lower CSF 5-HIAA levels than Indian-derived monkeys. Blood and cerebrospinal fluid samples were obtained on Days, 14, 30, 60, 90, 120, and 150 of life, and prior to and during social separations at 6 months of age. Behavioral observations were conducted in the home cage and during the separation condition. No differences in behavior were observed between hybrid and Indian-derived animals in the home cage. Indian-derived and hybrid infants exhibited diverging patterns of behavioral reactivity across the 4 weeks of the repetitive social-separation procedure, and during reunion periods. Although plasma cortisol levels were sensitive to the testing conditions, no group differences were observed. CSF 5-HIAA declined over time for all monkeys, and hybrid animals exhibited significantly lower 5-HIAA levels than Indian monkeys beginning at 6 months of age. These findings are consistent with the known behavioral and physiological characteristics of Chinese-origin adult rhesus. PMID:9222116

  12. Effect of a one-semester conditioning class on physiological characteristics of college students.

    PubMed

    Danoff, Jerome V; Raupers, Erin G

    2014-11-01

    Long-term exercise is known to have positive effects on the health of adults. Some college "activity" courses are designed to give participants exposure to, and practice with, safe exercise techniques. Whether these 1-semester courses, usually 12-14 weeks, are sufficient to alter physiological characteristics, such as blood pressure or strength, has not been established. Therefore, the purpose of our investigation was to evaluate physiological and performance measures in college students to determine whether changes would result after 14 weeks of a general conditioning activity course. This study involved 79 students from several sections of exercise and conditioning classes at our university. Classes included a variety of fitness- and strength-oriented exercises. Physiological and performance measurements were collected in weeks 2 (pretest) and 14 (posttest), and compared pre with post using paired t-tests subject to Bonferroni correction (significant p < 0.0055). There were significant improvements in resting heart rate (HR) (73 vs. 70 b·min, p < 0.002), hand grip strength (250 vs. 272 N, p < 0.001), push-ups (29 vs 37, p < 0.001), sit-ups (32 vs. 35, p < 0.001), and step test HR recovery (122 vs. 110 b·min, p < 0.001). Systolic and diastolic blood pressures, body weight, and percent body fat did not change. These results suggest that 14 weeks of regular exercise in an organized college-based activity class can result in significant improvements in some measures of fitness and strength in college-aged participants.

  13. Characteristics of physiological inducers of the ethanol utilization (alc) pathway in Aspergillus nidulans.

    PubMed Central

    Flipphi, Michel; Kocialkowska, Janina; Felenbok, Béatrice

    2002-01-01

    The ethanol utilization (alc) pathway in Aspergillus nidulans is one of the strongest expressed gene systems in filamentous fungi. The pathway-specific activator AlcR requires the presence of an inducing compound to activate transcription of genes under its control. We have demonstrated recently that acetaldehyde is the sole physiological inducer of ethanol catabolism. In the present study we show that compounds with catabolism related to that of ethanol, i.e. primary alcohols, primary monoamines and l-threonine, act as inducers because their breakdown results in the production of inducing aliphatic aldehydes. Such aldehydes were shown to induce the alc genes efficiently at low external concentrations. When ethanol is mixed with representatives of another class of strong direct inducers, ketones, the physiological inducer, acetaldehyde, prevails as effector. Although direct inducers essentially carry a carbonyl function, not all aldehydes and ketones act as inducers. Structural features discriminating non-inducing from inducing compounds concern: (i) the length of the aliphatic side group(s); (ii) the presence and nature of any non-aliphatic substituent. These characteristics enable us to predict whether or not a given carbonyl compound will induce the alc genes. PMID:11988072

  14. Eco-physiological characteristics of alfalfa seedlings in response to various mixed salt-alkaline stresses.

    PubMed

    Peng, Yong-Lin; Gao, Zhan-Wu; Gao, Ying; Liu, Guo-Fang; Sheng, Lian-Xi; Wang, De-Li

    2008-01-01

    Soil salinization and alkalization frequently co-occur in nature, but little is known about the mixed effects of salt-alkaline stresses on plants. An experiment with mixed salts (NaCl, Na(2)SO(4), NaHCO(3) and Na(2)CO(3)) and 30 salt-alkaline combinations (salinity 24-120 mmol/L and pH 7.03-10.32) treating Medicago sativa seedlings was conducted. The results demonstrated that salinity and alkalinity significantly affected total biomass and biomass components of seedlings. There were interactive effects of salt composition and concentration on biomass (Pphysiological responses (leaf electrolyte leakage rate and proline content) in order to adapt to mixed salt-alkaline stresses. It was concluded that the mixed salt-alkaline stresses, which differ from either salt or alkali stress, emphasize the significant interaction between salt concentration (salinity) and salt component (alkalinity). Further, the effects of the interaction between high alkalinity and salinity are more severe than those of either salt or alkali stress, and such a cooperative interaction results in more sensitive responses of ecological and physiological characteristics in plants. PMID:18666949

  15. Microbiological Characteristics and Physiological Functionality of New Records of Yeasts from Wild Flowers in Yokjido, Korea

    PubMed Central

    Hyun, Se-Hee

    2014-01-01

    Two new yeast records, Cryptococcus adeliensis YJ19-2 and Cryptococcus uzbekistanensis YJ10-4 were screened from 60 yeasts strains that were isolated and identified from wild flowers in Yokjido, Gyeongsangnam-do, Korea. The morphological and cultural characteristics of the newly recorded yeasts and the physiological functionalities of the supernatants and cell-free extracts obtained from their cultures were investigated. The two newly recorded yeasts did not form ascospores and pseudomycelia. They also grew well in yeast extract-peptone-dextrose broth. C. uzbekistanensis YJ10-4 grew in a vitamin-free medium and was also tolerant to sugar and salt. Antihypertensive angiotensin I-converting enzyme inhibitory activity of the supernatant from C. adeliensis YJ19-2 was high (71.8%) and its cell-free extract also showed very high (81.2%) antidiabetic á-glucosidase inhibitory activity. PMID:25071392

  16. [Effects of calcium fertilizer application on peanut growth, physiological characteristics, yield and quality under drought stress].

    PubMed

    Gu, Xue-hua; Sun, Lian-qiang; Gao, Bo; Sun, Qi-ze; Liu, Chen; Zhang, Jia-lei; Li, Xiang-dong

    2015-05-01

    An experiment was carried out to study the effects of different rates of calcium application on peanut growth, physiological characteristics, yield and quality under drought stress at pegging stage and pod setting stage in pool cultivation with rainproof, using variety 606 as experimental material. The results showed that applying Ca fertilizer under drought stress could promote peanut growth, increase the chlorophyll content, leaf photosynthetic rate and the root vitality, increase the recovery ability of peanut during rewatering after drought stress, alleviate the impact of drought stress on peanut. Applying Ca fertilizer under drought stress increased pod and kernel yields because of the increase of kernel rate and pod number per plant. It also increased the fat and protein contents of peanut kernel, and improved peanut kernel quality under drought stress. It was suggested that 300 kg · hm(-2) Ca application is the best choice to alleviate the impact of drought stress on peanut.

  17. [Effects of cinnamic acid on physiological characteristics of Cucumis sativus seedling].

    PubMed

    Wu, Fengzhi; Pan, Kai; Zhou, Xiuyan

    2005-05-01

    With substrate culture, this paper studied the effects of different concentrations of cinnamic acid on the physiological characteristics of Cucumis sativus seedling. The results showed that 25 micromol.L(-1) of cinnamic acid had an inhibition effect on carotenoids, but a promotion effect on chlorophyll a and b. 50 micromol.L(-1) of this compound could significantly inhibit the photosynthetic rate, transpiration rate and root activity (P < 0.05), and this effect was getting stronger when the concentration was higher. 150 micromol cinnamic acid.L(-1) had a significant inhibition effect on chlorophyll a and b (P < 0.05). Cinnamic acid had a weak inhibition effect on root activity when its concentration was low (25-50 micromol.L(-1)), but the effect was significant when the concentration was high (100-150 micromol.L(-1)), which became stronger with the longer handling time (P < 0.05).

  18. Physiological and biochemical characteristics of laboratory induced mutants of Botrytis cinerea with resistance to fluazinam.

    PubMed

    Shao, Wenyong; Zhang, Yu; Ren, Weichao; Chen, Changjun

    2015-01-01

    Botrytis cinerea is a necrotrophic and filamentous fungus with a high risk of developing resistance to fungicides. The pyridinamine fungicide fluazinam has been reported to have excellent activity against B. cinerea and better effect on controlling gray mold. In this study, the physiological and biochemical characteristics of laboratory-induced mutants of B. cinerea with resistance to fluazinam has been investigated. Compared to the wild-type strains, the fluazinam-resistant mutants had a significant decrease in respiratory rate, glycerol, oxalate, and ATP contents, and an increase in ATPase activity and sensitivity to osmotic pressure, but did not differ in cell membrane permeability. Sequencing indicated that two parental strains and four resistant mutants were identical in the nucleotide sequence of F-ATPase gene. These results will enrich our understanding of the resistance mechanism of B. cinerea to fluazinam.

  19. Water Landing Characteristics of a Reentry Capsule

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Water Landing Characteristics of a Reentry Capsule. Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions. [Entire movie available on DVD from CASI as Doc ID 20070030955. Contact help@sti.nasa.gov

  20. The science of badminton: game characteristics, anthropometry, physiology, visual fitness and biomechanics.

    PubMed

    Phomsoupha, Michael; Laffaye, Guillaume

    2015-04-01

    Badminton is a racket sport for two or four people, with a temporal structure characterized by actions of short duration and high intensity. This sport has five events: men's and women's singles, men's and women's doubles, and mixed doubles, each requiring specific preparation in terms of technique, control and physical fitness. Badminton is one of the most popular sports in the world, with 200 million adherents. The decision to include badminton in the 1992 Olympics Game increased participation in the game. This review focuses on the game characteristics, anthropometry, physiology, visual attributes and biomechanics of badminton. Players are generally tall and lean, with an ectomesomorphic body type suited to the high physiological demands of a match. Indeed, a typical match characteristic is a rally time of 7 s and a resting time of 15 s, with an effective playing time of 31%. This sport is highly demanding, with an average heart rate (HR) of over 90% of the player's maximal HR. The intermittent actions during a game are demanding on both the aerobic and anaerobic systems: 60-70% on the aerobic system and approximately 30% on the anaerobic system, with greater demand on the alactic metabolism with respect to the lactic anaerobic metabolism. The shuttlecock has an atypical trajectory, and the players perform specific movements such as lunging and jumping, and powerful strokes using a specific pattern of movement. Lastly, badminton players are visually fit, picking up accurate visual information in a short time. Knowledge of badminton can help to improve coaching and badminton skills. PMID:25549780

  1. Physiological characteristics of tropical rain forest tree species: a basis for the development of silvicultural technology.

    PubMed

    Sasaki, Satohiko

    2008-01-01

    The physiological characteristics of the dominant tree species in the tropical rain forest mainly belonging to dipterocarps as well as the environmental conditions especially for the light in the forest were studied to establish the silvicultural system for the forest regeneration in the tropical South Asia. The flowering patterns of the dipterocarp trees are usually irregular and unpredictable, which make difficult to collect sufficient seeds for raising the seedlings. The field survey revealed the diverged features of the so-called gregarious or simultaneous flowering of various species of this group. Appropriate conditions and methods for the storage of the seeds were established according to the detailed analyses of the morphological and physiological characteristics of the seeds such as the low temperature tolerance and the moisture contents. The intensity and spectra of the light in the forest primarily determine the growth and the morphological development of the seedlings under the canopy. Based on the measurements of the diffused light at the sites in the tropical forest in the varying sunlight, the parameters such as "the steady state of the diffuse light" and "the turning point" were defined, which were useful to evaluate the light conditions in the forest. To improve the survival of the transplanted seedlings, a planting method of "the bare-root seedlings", the seedlings easy to be handled by removal of all leaves, soil and pots, was developed. Its marked efficiency was proved with various dipterocarps and other tropical trees by the field trial in the practical scale. Tolerance of the various species to the extreme environmental conditions such as fires, acid soils and drought were examined by the experiments and the field survey, which revealed marked adaptability of Shorea roxburghii as a potential species for regeneration of the tropical forests.

  2. Physiological characteristics of tropical rain forest tree species: A basis for the development of silvicultural technology

    PubMed Central

    SASAKI, Satohiko

    2008-01-01

    The physiological characteristics of the dominant tree species in the tropical rain forest mainly belonging to dipterocarps as well as the environmental conditions especially for the light in the forest were studied to establish the silvicultural system for the forest regeneration in the tropical South Asia. The flowering patterns of the dipterocarp trees are usually irregular and unpredictable, which make difficult to collect sufficient seeds for raising the seedlings. The field survey revealed the diverged features of the so-called gregarious or simultaneous flowering of various species of this group. Appropriate conditions and methods for the storage of the seeds were established according to the detailed analyses of the morphological and physiological characteristics of the seeds such as the low temperature tolerance and the moisture contents. The intensity and spectra of the light in the forest primarily determine the growth and the morphological development of the seedlings under the canopy. Based on the measurements of the diffused light at the sites in the tropical forest in the varying sunlight, the parameters such as “the steady state of the diffuse light” and “the turning point” were defined, which were useful to evaluate the light conditions in the forest. To improve the survival of the transplanted seedlings, a planting method of “the bare-root seedlings”, the seedlings easy to be handled by removal of all leaves, soil and pots, was developed. Its marked efficiency was proved with various dipterocarps and other tropical trees by the field trial in the practical scale. Tolerance of the various species to the extreme environmental conditions such as fires, acid soils and drought were examined by the experiments and the field survey, which revealed marked adaptability of Shorea roxburghii as a potential species for regeneration of the tropical forests. PMID:18941286

  3. [Effects of selenite addition on selenium absorption, root morphology and physiological characteristics of rape seedlings].

    PubMed

    Liu, Xin-wei; Wang, Qiao-lan; Duan, Bi-hui; Lin, Ya-meng; Zhao, Xiao-hu; Hu, Cheng-xiao; Zhao, Zhu-qing

    2015-07-01

    Abstract: The rape (Brassica napus L. cv. Xiangnongyou 571) was chosen as the experimental material to undergo solution cultivation at seedling stage to investigate the effects of selenite addition on the selenium (Se) absorption and distribution, root morphology and physiological characteristics of rape seedlings. The results showed that the bioaccumulation ability of Se decreased significantly with increasing the Se application rate, but the Se distribution coefficient remained around 0.9 with no significant influence. The application of 10 µmol . L-1 selenite stimulated the growth of rape seedlings through improving the root physiological characteristics and root morphology significantly, including significantly increasing the production of superoxide radical (O2∙-) rate and the activities of superoxide dismutase (SOD), peroxidase (POD) and fungal catalase (CAT) in the root system, which resulted in a reduction of the lipids peroxidation (MDA) content as much as 26.0%, consequently increasing the root activity as much as 17.4%. The promoting degrees of selenite on root morphological parameters were from strong to weak in such a tendency: root volume > total surface area > number of root forks > total root length > number of root tips > average diameter. However, such positive effects had no significant difference with those in treatment with 1 µmol . L-1 selenite, indicating that small amounts (≤ 10 Lmol . L-1) of selenite were able to increase the activity of antioxidant enzymes and reduce the content of MDA in root system, which could increase root activity and improve root morphology, hence increased the biomass of rape seedlings. PMID:26710631

  4. An analysis of playing positions in elite men's volleyball: considerations for competition demands and physiologic characteristics.

    PubMed

    Sheppard, Jeremy M; Gabbett, Tim J; Stanganelli, Luiz-Claudio Reeberg

    2009-09-01

    The purpose of this study was to investigate the physiologic demands, physiologic characteristics, and jumping ability of different playing positions in elite male volleyball players. The first investigation involved an analysis of 16 international men's volleyball matches. The second investigation involved an analysis of the anthropometric and jump performance characteristics of 142 Development National Team (DNT) and Senior National Team (SNT) international volleyball players. Mean (+/-SD) frequency of block jumps for Middles (11.00 +/- 3.14) was significantly greater than for Setters (6.25 +/- 2.87, p < 0.001) and Outsides (6.50 +/- 3.16, p < 0.001). Attack jumps were performed more frequently by Middles (7.75 +/- 1.88), and this was found to be significantly more than for Setters (0.38 +/- 1.06, p < 0.001) and Outsides (5.75 +/- 3.25, p < 0.01). Middles were taller than Outsides and Setters (p < 0.001). Consequently, Middles had a significantly higher reach and greater body mass than Outsides (p < 0.001, p < 0.003) and Setters (p < 0.001, p < 0.001). Both Middles and Outsides had superior countermovement vertical jump (CMVJ) and spike jump (SPJ) scores compared with Setters (p < 0.001). Position-specific comparisons between DNT players and SNT players demonstrated that the SNT players were superior in relative CMVJ and SPJ scores (p < 0.05), with a large magnitude of effect (d > 0.99). The results of this study highlight the large jumping and landing demands placed on the taller and heavier players in the middle position. In addition to establishing the magnitude of difference in jumping ability between junior and senior national team players, the results also provide a comprehensive data set that may assist with talent identification and talent development for aspiring male volleyball players. PMID:19675472

  5. Water protein dynamic coupling and new opportunities for probing it at low to physiological temperatures in aqueous solutions

    SciTech Connect

    Mamontov, Eugene; Chu, Xiang-Qiang

    2012-01-01

    Both the structure and dynamics of biomolecules are known to be essential for their biological function. In the dehydrated state, the function of biomolecules, such as proteins, is severely impeded, so hydration is required for bioactivity. The dynamics of the hydrated biomolecules and their hydration water are related - but how closely? The problem involves several layers of complexity. Even for water in the bulk state, the contribution from various dynamic components to the overall dynamics is not fully understood. In biological systems, the effects of confinement on the hydration water further complicate the picture. Even if the various components of the hydration water dynamics are properly understood, which of them are coupled to the protein dynamics, and how? The studies of protein dynamics over the wide temperature range, from physiological to low temperatures, provide some answers to these question. At low temperatures, both the protein and its hydration water behave as solids, with only vibrational degrees of freedom. As the temperature is increased, non-vibrational dynamic components start contributing to the measurable dynamics and eventually become dominant at physiological temperatures. Thus, the temperature dependence of the dynamics of protein and its hydration water may allow probing various dynamic components separately. In order to suppress the water freezing, the low-temperature studies of protein rely on either low-hydrated samples (essentially, hydrated protein powders), or cryo-protective solutions. Both approaches introduce the hydration environments not characteristic of the protein environments in living systems, which are typically aqueous protein solutions of various concentrations. In this paper, we discuss the coupling between the dynamic components of the protein and its hydration water by critical examining of the existing literature, and then propose that proteins can be studied in an aqueous solution that is remarkably similar in

  6. Metabolic and Physiological Characteristics of Novel Cultivars from Serpentinite Seep Fluids

    NASA Astrophysics Data System (ADS)

    Nelson, B.; Chowdhury, S.; Brazelton, W. J.; Schrenk, M. O.

    2011-12-01

    Subsurface waters associated with the alteration of ultramafic rocks become highly reducing and alkaline through a process known as serpentinization. As habitat, these fluids are in many ways metabolically constraining but can provide sufficient energy for chemolithotrophy. As part of an ongoing effort to characterize these communities, heterotrophic enrichment cultures and anaerobic microcosms were initiated with alkaline waters found at three geographically and geochemically distinct sites of active serpentinization. These include the Northern Apennine ophiolite in the Ligurian region of Italy, the Tablelands ophiolite at Gros Morne National Park, Canada and the Coast Range ophiolite at McLaughlin Natural Reserve, California. Enrichment cultures at pH 11 yielded numerous isolates related to Proteobacteria and Firmicutes, some of which are closely related to other cultivars from high pH and subsurface environments. Anaerobic water samples were amended with combinations of electron donors (hydrogen, complex organics, acetate) and acceptors (ferric iron, sulfate) in a block design. After several weeks of incubation, DNA was extracted from cell concentrations and community differences were compared by TRFLP. Of particular interest is the isolation of a putative iron reducing Firmicute from samples enriched with complex organic compounds and ferric citrate. Ongoing studies are aimed at characterizing the physiology of these isolates. These data provide important insights into the metabolic potential of serpentinite subsurface ecosystems, and are a complement to culture-independent genomic analyses.

  7. Water Landing Characteristics of a Reentry Capsule

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions.

  8. Time-motion analysis, heart rate, and physiological characteristics of international canoe polo athletes.

    PubMed

    Forbes, Scott C; Kennedy, Michael D; Bell, Gordon J

    2013-10-01

    To evaluate the time international canoe polo players spend performing various game activities, measure heart rate (HR) responses during games, and describe the physiological profile of elite players. Eight national canoe polo players were videotaped and wore HR monitors during 3 games at a World Championship and underwent fitness testing. The mean age, height, and weight were 25 ± 1 years, 1.82 ± 0.04 m, and 81.9 ± 10.9 kg, respectively. Time-motion analysis of 3 games indicated that the players spent 29 ± 3% of the game slow and moderate forward paddling, 28 ± 5% contesting, 27 ± 5% resting and gliding, 7 ± 1% turning, 5 ± 1% backward paddling, 2 ± 1% sprinting, and 2 ± 1% dribbling. Sixty-nine (±20)% of the game time was played at an HR intensity above the HR that corresponded to the ventilatory threshold (VT) that was determined during the peak V[Combining Dot Above]O2 test. Peak oxygen uptake and VT were 3.3 ± 0.3 and 2.2 ± 0.3 L·min, respectively, on a modified Monark arm crank ergometer. Arm crank peak 5-second anaerobic power was 379 W. The majority of the time spent during international canoe polo games involved slow-to-moderate forward paddling, contesting for the ball, and resting and gliding. Canoe polo games are played at a high intensity indicated by the HR responses, and the physiological characteristics suggest that these athletes had high levels of upper body aerobic and anaerobic fitness levels.

  9. Genotypic differences in architectural and physiological responses to water restriction in rose bush

    PubMed Central

    Li-Marchetti, Camille; Le Bras, Camille; Relion, Daniel; Citerne, Sylvie; Huché-Thélier, Lydie; Sakr, Soulaiman; Morel, Philippe; Crespel, Laurent

    2015-01-01

    The shape and, therefore, the architecture of the plant are dependent on genetic and environmental factors such as water supply. The architecture determines the visual quality, a key criterion underlying the decision to purchase an ornamental potted plant. The aim of this study was to analyze genotypic responses of eight rose bush cultivars to alternation of water restriction and re-watering periods, with soil water potential of -20 and -10 kPa respectively. Responses were evaluated at the architectural level through 3D digitalization using six architectural variables and at the physiological level by measuring stomatal conductance, water content, hormones [abscisic acid (ABA), auxin, cytokinins, jasmonic acid, and salicylic acid (SA)], sugars (sucrose, fructose, and glucose), and proline. Highly significant genotype and watering effects were revealed for all the architectural variables measured, as well as genotype × watering interaction, with three distinct genotypic architectural responses to water restriction – weak, moderate and strong – represented by Hw336, ‘Baipome’ and ‘The Fairy,’ respectively. The physiological analysis explained, at least in part, the more moderate architectural response of ‘Baipome’ compared to ‘The Fairy,’ but not that of Hw336 which is an interspecific hybrid. Such physiological responses in ‘Baipome’ could be related to: (i) the maintenance of the stimulation of budbreak and photosynthetic activity during water restriction periods due to a higher concentration in conjugated cytokinins (cCK) and to a lower concentration in SA; (ii) a better resumption of budbreak during the re-watering periods due to a lower concentration in ABA during this period. When associated with the six architectural descriptors, cCK, SA and ABA, which explained the genotypic differences in this study, could be used as selection criteria for breeding programs aimed at improving plant shape and tolerance to water restriction. PMID

  10. Anthropometric and physiological characteristics of Melanesian futsal players: a first approach to talent identification in Oceania

    PubMed Central

    Zongo, P; Chamari, K; Chaouachi, A; Michalak, E; Dellal, A; Castagna, C; Hue, O

    2015-01-01

    This study assessed the anthropometric and physiological characteristics of elite Melanesian futsal players in order to determine the best performance predictors. Physiological parameters of performance were measured in 14 Melanesian (MEL-G, 24.4±4.4 yrs) and 8 Caucasian (NMEL-G, 22.9±4.9) elite futsal players, using tests of jump-and-reach (CMJ), agility (T-Test), repeated sprint ability (RSA), RSA with change-of-direction (RSA-COD), sprints with 5 m, 10 m, 15 m, and 30 m lap times, and aerobic fitness with the 30-15 intermittent fitness test (30-15 IFT). The anthropometric data revealed significantly lower height for MEL-G compared with NMEL-G: 1.73±0.05 and 1.80±0.08 m, respectively; P = 0.05. The CMJ was significantly higher for MEL-G than NMEL-G: 50.4±5.9 and 45.2±4.3 cm, respectively; P = 0.05. T-Test times were significantly lower for MEL-G than NMEL-G: 10.47±0.58 and 11.01±0.64 seconds, respectively; P = 0.05. MEL-G height was significantly related to CMJ (r = 0.706, P = 0.01), CMJpeakP (r = 0.709, P = 0.01) and T-Test (r = 0.589, P = 0.02). No significant between-group differences were observed for sprint tests or 30-15 IFT, including heart rate and estimated VO2max. Between groups, the percentage decrement (%Dec) in RSA-COD was significantly lower in MEL-G than NMEL-G (P = 0.05), although no significant difference was noted between RSA and RSA-COD. Within groups, no significant difference was observed between %Dec in RSA or RSA-COD; P = 0.697. This study presents specific anthropometric (significantly lower height) and physiological (significantly greater agility) reference values in Melanesians, which, taken together, might help coaches and physical fitness trainers to optimize elite futsal training and talent identification in Oceania. PMID:26060337

  11. Physiological characteristics of wild Atlantic salmon post-smolts during estuarine and coastal migration

    USGS Publications Warehouse

    Stefansson, S.O.; Bjornsson, B. Th; Sundell, K.; Nyhammer, G.; McCormick, S.D.

    2003-01-01

    Changes were measured in some of the major physiological variables associated with seawater adaptability, growth and energetics in wild Atlantic salmon Salmo salar smolts and post-smolts migrating from the river and through the estuary, fjord and coastal areas in the River Orkla and the Trondheimsfjord, Norway during late May to early June. Gill Na+,K+-ATPase activity increased to levels of 12-16 ??mol ADP mg protein-1 h -1 in post-smolts caught in higher salinity zones, probably representing long-term levels of Atlantic salmon post-smolts in oceanic conditions. Muscle moisture was regulated within narrow limits (77.7-78.7%) in fish from all zones during both years, suggesting that post-smolts adapt to marine conditions without any long-term disturbance of hydro-mineral balance. Lipid and glycogen content showed a general trend towards depletion from the river, through the fjord and into the ocean. There was, however, no significant change in protein content. The present results confirm that smolts are naturally 'energy deficient' during downstream migration, and suggest that post-smolts also mobilize energy reserves during their early marine phase, while protein is allocated for somatic growth. Plasma growth hormone (GH) levels increased transiently during passage through the estuary and fjord, with lower levels observed in post-smolts caught off-shore, i.e. in fish which were feeding on marine prey and had adapted to the marine environment. These physiological changes may confer substantial selective advantages during the critical early marine phase of anadromous salmonids, and hence are adaptive for long-term survival in sea water. ?? 2003 The Fisheries Society of the British Isles.

  12. Physiological, anatomical and transcriptional alterations in a rice mutant leading to enhanced water stress tolerance

    PubMed Central

    Lima, John Milton; Nath, Manoj; Dokku, Prasad; Raman, K. V.; Kulkarni, K. P.; Vishwakarma, C.; Sahoo, S. P.; Mohapatra, U. B.; Mithra, S. V. Amitha; Chinnusamy, V.; Robin, S.; Sarla, N.; Seshashayee, M.; Singh, K.; Singh, A. K.; Singh, N. K.; Sharma, R. P.; Mohapatra, T.

    2015-01-01

    Water stress is one of the most severe constraints to crop productivity. Plants display a variety of physiological and biochemical responses both at the cellular and whole organism level upon sensing water stress. Leaf rolling, stomatal closure, deeper root penetration, higher relative water content (RWC) and better osmotic adjustment are some of the mechanisms that plants employ to overcome water stress. In the current study, we report a mutant, enhanced water stress tolerant1 (ewst1) with enhanced water stress tolerance, identified from the ethyl methanesulfonate-induced mutant population of rice variety Nagina22 by field screening followed by withdrawal of irrigation in pots and hydroponics (PEG 6000). Though ewst1 was morphologically similar to the wild type (WT) for 35 of the 38 morphological descriptors (except chalky endosperm/expression of white core, decorticated grain colour and grain weight), it showed enhanced germination in polyethylene glycol-infused medium. It exhibited increase in maximum root length without any significant changes in its root weight, root volume and total root number on crown when compared with the WT under stress in PVC tube experiment. It also showed better performance for various physiological parameters such as RWC, cell membrane stability and chlorophyll concentration upon water stress in a pot experiment. Root anatomy and stomatal microscopic studies revealed changes in the number of xylem and phloem cells, size of central meta-xylem and number of closed stomata in ewst1. Comparative genome-wide transcriptome analysis identified genes related to exocytosis, secondary metabolites, tryptophan biosynthesis, protein phosphorylation and other signalling pathways to be playing a role in enhanced response to water stress in ewst1. The possible involvement of a candidate gene with respect to the observed morpho-physiological and transcriptional changes and its role in stress tolerance are discussed. The mutant identified and

  13. A novel ammonia-oxidizing archaeon from wastewater treatment plant: Its enrichment, physiological and genomic characteristics

    NASA Astrophysics Data System (ADS)

    Li, Yuyang; Ding, Kun; Wen, Xianghua; Zhang, Bing; Shen, Bo; Yang, Yunfeng

    2016-03-01

    Ammonia-oxidizing archaea (AOA) are recently found to participate in the ammonia removal processes in wastewater treatment plants (WWTPs), similar to their bacterial counterparts. However, due to lack of cultivated AOA strains from WWTPs, their functions and contributions in these systems remain unclear. Here we report a novel AOA strain SAT1 enriched from activated sludge, with its physiological and genomic characteristics investigated. The maximal 16S rRNA gene similarity between SAT1 and other reported AOA strain is 96% (with “Ca. Nitrosotenuis chungbukensis”), and it is affiliated with Wastewater Cluster B (WWC-B) based on amoA gene phylogeny, a cluster within group I.1a and specific for activated sludge. Our strain is autotrophic, mesophilic (25 °C–33 °C) and neutrophilic (pH 5.0–7.0). Its genome size is 1.62 Mb, with a large fragment inversion (accounted for 68% genomic size) inside. The strain could not utilize urea due to truncation of the urea transporter gene. The lack of the pathways to synthesize usual compatible solutes makes it intolerant to high salinity (>0.03%), but could adapt to low salinity (0.005%) environments. This adaptation, together with possibly enhanced cell-biofilm attachment ability, makes it suitable for WWTPs environment. We propose the name “Candidatus Nitrosotenuis cloacae” for the strain SAT1.

  14. Insight into characteristic features of cartilage growth plate as a physiological template for bone formation.

    PubMed

    Jaroszewicz, Jakub; Kosowska, Anna; Hutmacher, Dietmar; Swieszkowski, Wojciech; Moskalewski, Stanisław

    2016-02-01

    Cartilage growth plate is a natural template from both a biochemical and structural point of view and allows osteoblasts migration, proliferation, differentiation, and ultimately, bone formation. It is evolutionary adjusted to support bone formation within strictly defined spatial framework serving as an interesting model for studying more mechanistically aspects which might be important for specific scaffold-based bone tissue engineering strategies. Surprisingly little is known about the geometric features of this physiological template. To this purpose we analyzed cartilage growth plate from rat, mouse, and human costochondral junction and tibia. High-resolution X-ray tomography showed that pore size in the zone of provisional calcification was within 20 to 30 µm range and in the metaphysis in 35 to 50 µm range. The thickness of calcified longitudinal septa in zone of provisional calcification was 3 to 5 µm and in metaphysis 7 to 12 µm. The porosity varied from 84 to 88%. We observed that numerical values characteristic for cartilage growth plate were not significantly influenced by the species of origin, by the type of bone, or by age. In addition, electron microscopy of calcified fragments of longitudinal septa showed that the calcium aggregates were globular, connected with each other, and formed a shell covering cartilage matrix located within longitudinal septa.

  15. Profiling of Intracellular Metabolites: An Approach to Understanding the Characteristic Physiology of Mycobacterium leprae

    PubMed Central

    Miyamoto, Yuji; Mukai, Tetsu; Matsuoka, Masanori; Kai, Masanori; Maeda, Yumi; Makino, Masahiko

    2016-01-01

    Mycobacterium leprae is the causative agent of leprosy and also known to possess unique features such as inability to proliferate in vitro. Among the cellular components of M. leprae, various glycolipids present on the cell envelope are well characterized and some of them are identified to be pathogenic factors responsible for intracellular survival in host cells, while other intracellular metabolites, assumed to be associated with basic physiological feature, remain largely unknown. In the present study, to elucidate the comprehensive profile of intracellular metabolites, we performed the capillary electrophoresis-mass spectrometry (CE-MS) analysis on M. leprae and compared to that of M. bovis BCG. Interestingly, comparison of these two profiles showed that, in M. leprae, amino acids and their derivatives are significantly accumulated, but most of intermediates related to central carbon metabolism markedly decreased, implying that M. leprae possess unique metabolic features. The present study is the first report demonstrating the unique profiles of M. leprae metabolites and these insights might contribute to understanding undefined metabolism of M. leprae as well as pathogenic characteristics related to the manifestation of the disease. PMID:27479467

  16. Physiological characteristics of the extreme thermophile Caldicellulosiruptor saccharolyticus: an efficient hydrogen cell factory

    PubMed Central

    2010-01-01

    Global concerns about climate changes and their association with the use of fossil fuels have accelerated research on biological fuel production. Biological hydrogen production from hemicellulose-containing waste is considered one of the promising avenues. A major economical issue for such a process, however, is the low substrate conversion efficiency. Interestingly, the extreme thermophilic bacterium Caldicellulosiruptor saccharolyticus can produce hydrogen from carbohydrate-rich substrates at yields close to the theoretical maximum of the dark fermentation process (i.e., 4 mol H2/mol hexose). The organism is able to ferment an array of mono-, di- and polysaccharides, and is relatively tolerant to high partial hydrogen pressures, making it a promising candidate for exploitation in a biohydrogen process. The behaviour of this Gram-positive bacterium bears all hallmarks of being adapted to an environment sparse in free sugars, which is further reflected in its low volumetric hydrogen productivity and low osmotolerance. These two properties need to be improved by at least a factor of 10 and 5, respectively, for a cost-effective industrial process. In this review, the physiological characteristics of C. saccharolyticus are analyzed in view of the requirements for an efficient hydrogen cell factory. A special emphasis is put on the tight regulation of hydrogen production in C. saccharolyticus by both redox and energy metabolism. Suggestions for strategies to overcome the current challenges facing the potential use of the organism in hydrogen production are also discussed. PMID:21092203

  17. [Impacts of salt stress on the growth and physiological characteristics of Panicum virgatum seedlings].

    PubMed

    Fan, Xi-Feng; Hou, Xin-Cun; Zhu, Yi; Wu, Ju-Ying

    2012-06-01

    An experiment was conducted in an artificial climate chamber to study the growth and physiological characteristics of switchgrass (Panicum virgatum) seedlings exposed to 0, 50, 100, 150, and 200 mmol x L(-1) of NaCl solutions. With the increasing concentration of the NaCl, the seedling growth was obviously inhibited. The plant height decreased, leaves became smaller, photosynthetic leaf area and net photosynthetic rate reduced, and dry matter accumulation decreased significantly, presenting the general traits of glycophyte. Meanwhile, the seedlings also showed relatively high salt tolerance. After exposed to 200 mmol x L(-1) of NaCl for 30 days, the seedlings still survived, with the green leaf area per plant and net photosynthetic rate being 491.9 cm2 and 0.93 micromol CO2 x m(-2) x s(-1), respectively. In this experiment, the salt tolerance threshold for P. virgatum was 178.6 mmol L(-1) when taking 50% drop in biomass as the standard.

  18. Physiology and molecular characteristics of a pine wilt nematode-trapping fungus, Monacrosporium megalosporum.

    PubMed

    Kano, Sanae; Aimi, Tadanori; Masumoto, Seita; Kitamoto, Yutaka; Morinaga, Tsutomu

    2004-09-01

    We isolated the nematode-trapping fungus Monacrosporium megalosporum from nature and examined its morphology, physiology and molecular characteristics. The nematode-trapping device of this fungus is a three-dimensional network. This fungus captures the pine wilt nematode (Bursaphelenchus xylophilus), but not a non-phytopathogenic nematode that is morphologically similar to B. xylophilus. The phylogenic relationship of the nucleotide sequence of the rDNA ITS region was close to those of M. thaumasium and Geniculifera eudermata, which also have nematode-trapping devices that are three-dimensional networks. Acidic pH inhibited both the liberation and regeneration of protoplasts. Moreover, cytoplasmic granulation of protoplasts was found below pH 6.0. Mycelial growth on agar media was also inhibited below pH 4, but not at pH 9. These results strongly suggest that the activity of this fungus is inhibited by acid rain in the field. Therefore, development of pine wilt disease might be a secondary effect of acid rain.

  19. Biodiversity and physiological characteristics of Antarctic and Arctic lichens-associated bacteria.

    PubMed

    Lee, Yung Mi; Kim, Eun Hye; Lee, Hong Kum; Hong, Soon Gyu

    2014-10-01

    The diversity and physiological characteristics of culturable bacteria associated with lichens from different habitats of the Arctic and Antarctica were investigated. The 68 retrieved isolates could be grouped on the basis of their 16S rRNA gene sequences into 26 phylotypes affiliated with the phyla Actinobacteria, Bacteroidetes, Deinococcus-Thermus, and Firmicutes and with the classes Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria. Isolates belonging to the Alphaproteobacteria were the most abundant, followed by those belonging to Actinobacteria, Betaproteobacteria, Gammaproteobacteria, Bacteroidetes, Firmicutes, and Deinococcus-Thermus. Phylogenetic analysis showed that approximately 21 % of the total isolates represented a potentially novel species or genus (≤97 % sequence similarity). Strains belonging to the genera Sphingomonas, Frondihabitans, Hymenobacter, and Burkholderia were recovered from lichen samples from both geographic locations, implying common and important bacterial functions within lichens. Extracellular protease activities were detected in six isolates, affiliated with Burkholderia, Frondihabitans, Hymenobacter, Pseudomonas, and Rhodanobacter. Extracellular lipase activities were detected in 37 isolates of the genera Burkholderia, Deinococcus, Frondihabitans, Pseudomonas, Rhodanobacter, Sphingomonas, and Subtercola. This is the first report on the culturable bacterial diversity present within lichens from Arctic and Antarctica and the isolates described herein are valuable resources to decode the functional and ecological roles of bacteria within lichens. In addition, the low similarity (≤97 %) of the recovered isolates to known species and their production of cold-active enzymes together suggest that lichens are noteworthy sources of novel bacterial strains for use in biotechnological applications.

  20. A novel ammonia-oxidizing archaeon from wastewater treatment plant: Its enrichment, physiological and genomic characteristics.

    PubMed

    Li, Yuyang; Ding, Kun; Wen, Xianghua; Zhang, Bing; Shen, Bo; Yang, Yunfeng

    2016-01-01

    Ammonia-oxidizing archaea (AOA) are recently found to participate in the ammonia removal processes in wastewater treatment plants (WWTPs), similar to their bacterial counterparts. However, due to lack of cultivated AOA strains from WWTPs, their functions and contributions in these systems remain unclear. Here we report a novel AOA strain SAT1 enriched from activated sludge, with its physiological and genomic characteristics investigated. The maximal 16S rRNA gene similarity between SAT1 and other reported AOA strain is 96% (with "Ca. Nitrosotenuis chungbukensis"), and it is affiliated with Wastewater Cluster B (WWC-B) based on amoA gene phylogeny, a cluster within group I.1a and specific for activated sludge. Our strain is autotrophic, mesophilic (25 °C-33 °C) and neutrophilic (pH 5.0-7.0). Its genome size is 1.62 Mb, with a large fragment inversion (accounted for 68% genomic size) inside. The strain could not utilize urea due to truncation of the urea transporter gene. The lack of the pathways to synthesize usual compatible solutes makes it intolerant to high salinity (>0.03%), but could adapt to low salinity (0.005%) environments. This adaptation, together with possibly enhanced cell-biofilm attachment ability, makes it suitable for WWTPs environment. We propose the name "Candidatus Nitrosotenuis cloacae" for the strain SAT1. PMID:27030530

  1. A novel ammonia-oxidizing archaeon from wastewater treatment plant: Its enrichment, physiological and genomic characteristics

    PubMed Central

    Li, Yuyang; Ding, Kun; Wen, Xianghua; Zhang, Bing; Shen, Bo; Yang, Yunfeng

    2016-01-01

    Ammonia-oxidizing archaea (AOA) are recently found to participate in the ammonia removal processes in wastewater treatment plants (WWTPs), similar to their bacterial counterparts. However, due to lack of cultivated AOA strains from WWTPs, their functions and contributions in these systems remain unclear. Here we report a novel AOA strain SAT1 enriched from activated sludge, with its physiological and genomic characteristics investigated. The maximal 16S rRNA gene similarity between SAT1 and other reported AOA strain is 96% (with “Ca. Nitrosotenuis chungbukensis”), and it is affiliated with Wastewater Cluster B (WWC-B) based on amoA gene phylogeny, a cluster within group I.1a and specific for activated sludge. Our strain is autotrophic, mesophilic (25 °C–33 °C) and neutrophilic (pH 5.0–7.0). Its genome size is 1.62 Mb, with a large fragment inversion (accounted for 68% genomic size) inside. The strain could not utilize urea due to truncation of the urea transporter gene. The lack of the pathways to synthesize usual compatible solutes makes it intolerant to high salinity (>0.03%), but could adapt to low salinity (0.005%) environments. This adaptation, together with possibly enhanced cell-biofilm attachment ability, makes it suitable for WWTPs environment. We propose the name “Candidatus Nitrosotenuis cloacae” for the strain SAT1. PMID:27030530

  2. [Effects of sodium naphthalene acetate on growth and physiological characteristics of tomato seedlings under suboptimal temperature and light condition].

    PubMed

    Guo, Yun-na; Li, Yan-su; He, Chao-xing; Yu, Xian-chang

    2015-10-01

    Taking tomato 'Zhongza 105' as test material, the influences of sodium naphthalene acetate (SNA) on growth and physiological characteristics of tomato seedlings under suboptimal temperature and light condition were investigated. The results showed that the dry mass, vigorous seedling index, root activity, total nitrogen content, net photosynthesis rate (Pn) of tomato seedlings were significantly decreased by suboptimum temperature and light treatment. In addition, the catalase activity and zeatin riboside (ZR) concentration were also reduced. However, the superoxide dismutase, peroxidase activity and the content of abscisic acid (ABA) were increased. Compared with treatment of the same volume distilled water on tomato seedlings under suboptimum temperature and light condition, the dry mass of whole plant and vigorous seedling index of tomato seedlings were significantly increased by 16.4% and 22.9%, as the total N contents in roots and leaves and Pn were also increased by 8.5%, 28.5%and 37.0%, respectively, with the treatment of root application of 10 mg . L-1 SNA. Besides protective enzyme activity and the root activity were improved, the indole acetic acid (IAA) and ZR concentration of tomato were raised, and ABA concentration was reduced. The results indicated that root application of certain concentration of SNA could promote the growth of tomato seedlings by increasing the tomato root activity, protective enzymes activity, Pn and regulating endogenous hormone concentration under suboptimum temperature and light condition. PMID:26995913

  3. Growth and Physiological Responses to Water Depths in Carex schmidtii Meinsh

    PubMed Central

    Yan, Hong; Liu, Ruiquan; Liu, Zinan; Wang, Xue; Luo, Wenbo; Sheng, Lianxi

    2015-01-01

    A greenhouse experiment was performed to investigate growth and physiological responses to water depth in completely submerged condition of a wetland plant Carex schmidtii Meinsh., one of the dominant species in the Longwan Crater Lake wetlands (China). Growth and physiological responses of C. schmidtii were investigated by growing under control (non-submerged) and three submerged conditions (5 cm, 15 cm and 25 cm water level). Total biomass was highest in control, intermediate in 5 cm treatment and lowest in the other two submerged treatments. Water depth prominently affected the first-order lateral root to main root mass ratio. Alcohol dehydrogenase (ADH) activity decreased but malondialdehyde (MDA) content increased as water depth increased. The starch contents showed no differences among the various treatments at the end of the experiment. However, soluble sugar contents were highest in control, intermediate in 5 cm and 15 cm treatments and lowest in 25 cm treatment. Our data suggest that submergence depth affected some aspects of growth and physiology of C. schmidtii, which can reduce anoxia damage not only through maintaining the non-elongation strategy in shoot part but also by adjusting biomass allocation to different root orders rather than adjusting root-shoot biomass allocation. PMID:26009895

  4. Growth and Physiological Responses to Water Depths in Carex schmidtii Meinsh.

    PubMed

    Yan, Hong; Liu, Ruiquan; Liu, Zinan; Wang, Xue; Luo, Wenbo; Sheng, Lianxi

    2015-01-01

    A greenhouse experiment was performed to investigate growth and physiological responses to water depth in completely submerged condition of a wetland plant Carex schmidtii Meinsh., one of the dominant species in the Longwan Crater Lake wetlands (China). Growth and physiological responses of C. schmidtii were investigated by growing under control (non-submerged) and three submerged conditions (5 cm, 15 cm and 25 cm water level). Total biomass was highest in control, intermediate in 5 cm treatment and lowest in the other two submerged treatments. Water depth prominently affected the first-order lateral root to main root mass ratio. Alcohol dehydrogenase (ADH) activity decreased but malondialdehyde (MDA) content increased as water depth increased. The starch contents showed no differences among the various treatments at the end of the experiment. However, soluble sugar contents were highest in control, intermediate in 5 cm and 15 cm treatments and lowest in 25 cm treatment. Our data suggest that submergence depth affected some aspects of growth and physiology of C. schmidtii, which can reduce anoxia damage not only through maintaining the non-elongation strategy in shoot part but also by adjusting biomass allocation to different root orders rather than adjusting root-shoot biomass allocation.

  5. Comparative reproductive and physiological responses of northern bobwhite and scaled quail to water deprivation

    USGS Publications Warehouse

    Giuliano, W.M.; Patino, R.; Lutz, R.S.

    1998-01-01

    We compared reproductive and physiological responses of captive female northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) under control and water deprivation conditions. Scaled quail required less food and water to reproduce successfully under control conditions than northern bobwhite. Additionally, in scaled quail, serum osmolality levels and kidney mass were unaffected by water deprivation, whereas in northern bobwhite, serum osmolality levels increased and kidney mass declined. This finding indicates that scaled quail may have osmoregulatory abilities superior to those of northern bobwhite. Under control conditions, northern bobwhite gained more body mass and produced more but smaller eggs than scaled quail. Under water deprivation conditions, northern bobwhite lost more body mass but had more laying bens with a higher rate of egg production than scaled quail. Our data suggest that northern bobwhite allocated more resources to reproduction than to body maintenance, while scaled quail apparently forego reproduction in favor of body maintenance during water deprivation conditions.

  6. Physiologic responses to water immersion in man: A compendium of research

    NASA Technical Reports Server (NTRS)

    Kollias, J.; Vanderveer, D.; Dorchak, K. J.; Greenleaf, J. E.

    1976-01-01

    A total of 221 reports published through December 1973 in the area of physiologic responses to water immersion in man were summarized. The author's abstract or summary was used whenever possible. Otherwise, a detailed annotation was provided under the subheadings: (1) purpose, (2) procedures and methods, (3) results, and (4) conclusions. The annotations are in alphabetical order by first author; author and subject indexes are included. Additional references are provided in the selected bibliography.

  7. Assessing physiological responses of dune forest functional groups to changing water availability: from Tropics to Mediterranean.

    NASA Astrophysics Data System (ADS)

    Antunes, Cristina; Lo Cascio, Mauro; Correia, Otília; Vieira, Simone; Cruz Diaz Barradas, Maria; Zunzunegui, Maria; Ramos, Margarida; João Pereira, Maria; Máguas, Cristina

    2014-05-01

    Alterations in water availability are important to vegetation as can produce dramatic changes in plant communities, on physiological performance or survival of plant species. Particularly, groundwater lowering and surface water diversions will affect vulnerable coastal dune forests, ecosystems particularly sensitive to groundwater limitation. Reduction of water tables can prevent the plants from having access to one of their key water sources and inevitably affect groundwater-dependent species. The additional impact of drought due to climatic change on groundwater-dependent ecosystems has become of increasing concern since it aggravates groundwater reduction impacts with consequent uncertainties about how vegetation will respond over the short and long term. Sand dune plant communities encompass a diverse number of species that differ widely in root depth, tolerance to drought and capacity to shift between seasonal varying water sources. Plant functional groups may be affected by water distribution and availability differently. The high ecological diversity of sand dune forests, characterized by sandy soils, well or poorly drained, poor in nutrients and with different levels of salinity, can occur in different climatic regions of the globe. Such is the case of Tropical, Meso-mediterranean and Mediterranean areas, where future climate change is predicted to change water availability. Analyses of the relative natural abundances of stable isotopes of carbon (13C/12C) and oxygen (18O/16O) have been used across a wide range of scales, contributing to our understanding of plant ecology and interactions. This approach can show important temporal and spatial changes in utilization of different water sources by vegetation. Accordingly, the core idea of this work is to evaluate, along a climatic gradient, the responses and capacity of different coastal plant communities to adapt to changing water availability. This large-climatic-scale study, covering Brazil, Portugal and

  8. Physiological response of the cold-water coral Desmophyllum dianthus to thermal stress and ocean acidification.

    PubMed

    Gori, Andrea; Ferrier-Pagès, Christine; Hennige, Sebastian J; Murray, Fiona; Rottier, Cécile; Wicks, Laura C; Roberts, J Murray

    2016-01-01

    Rising temperatures and ocean acidification driven by anthropogenic carbon emissions threaten both tropical and temperate corals. However, the synergistic effect of these stressors on coral physiology is still poorly understood, in particular for cold-water corals. This study assessed changes in key physiological parameters (calcification, respiration and ammonium excretion) of the widespread cold-water coral Desmophyllum dianthus maintained for ∼8 months at two temperatures (ambient 12 °C and elevated 15 °C) and two pCO2 conditions (ambient 390 ppm and elevated 750 ppm). At ambient temperatures no change in instantaneous calcification, respiration or ammonium excretion rates was observed at either pCO2 levels. Conversely, elevated temperature (15 °C) significantly reduced calcification rates, and combined elevated temperature and pCO2 significantly reduced respiration rates. Changes in the ratio of respired oxygen to excreted nitrogen (O:N), which provides information on the main sources of energy being metabolized, indicated a shift from mixed use of protein and carbohydrate/lipid as metabolic substrates under control conditions, to less efficient protein-dominated catabolism under both stressors. Overall, this study shows that the physiology of D. dianthus is more sensitive to thermal than pCO2 stress, and that the predicted combination of rising temperatures and ocean acidification in the coming decades may severely impact this cold-water coral species.

  9. Physiological response of the cold-water coral Desmophyllum dianthus to thermal stress and ocean acidification

    PubMed Central

    Ferrier-Pagès, Christine; Hennige, Sebastian J.; Murray, Fiona; Rottier, Cécile; Wicks, Laura C.; Roberts, J. Murray

    2016-01-01

    Rising temperatures and ocean acidification driven by anthropogenic carbon emissions threaten both tropical and temperate corals. However, the synergistic effect of these stressors on coral physiology is still poorly understood, in particular for cold-water corals. This study assessed changes in key physiological parameters (calcification, respiration and ammonium excretion) of the widespread cold-water coral Desmophyllum dianthus maintained for ∼8 months at two temperatures (ambient 12 °C and elevated 15 °C) and two pCO2 conditions (ambient 390 ppm and elevated 750 ppm). At ambient temperatures no change in instantaneous calcification, respiration or ammonium excretion rates was observed at either pCO2 levels. Conversely, elevated temperature (15 °C) significantly reduced calcification rates, and combined elevated temperature and pCO2 significantly reduced respiration rates. Changes in the ratio of respired oxygen to excreted nitrogen (O:N), which provides information on the main sources of energy being metabolized, indicated a shift from mixed use of protein and carbohydrate/lipid as metabolic substrates under control conditions, to less efficient protein-dominated catabolism under both stressors. Overall, this study shows that the physiology of D. dianthus is more sensitive to thermal than pCO2 stress, and that the predicted combination of rising temperatures and ocean acidification in the coming decades may severely impact this cold-water coral species. PMID:26855864

  10. Dynamic characteristics of gas-water interfacial plasma under water

    SciTech Connect

    Zheng, S. J.; Zhang, Y. C.; Ke, B.; Ding, F.; Tang, Z. L.; Yang, K.; Zhu, X. D.

    2012-06-15

    Gas-water interfacial plasmas under water were generated in a compact space in a tube with a sandglass-like structure, where two metal wires were employed as electrodes with an applied 35 kHz ac power source. The dynamic behaviors of voltage/current were investigated for the powered electrode with/without water cover to understand the effect of the gas-water interface. It is found that the discharge exhibits periodic pulsed currents after breakdown as the powered electrode is covered with water, whereas the electrical current reveals a damped oscillation with time with a frequency about 10{sup 6} Hz as the powered electrode is in a vapor bubble. By increasing water conductivity, a discharge current waveform transition from pulse to oscillation presents in the water covering case. These suggest that the gas-water interface has a significant influence on the discharge property.

  11. Response of the physiological parameters of mango fruit (transpiration, water relations and antioxidant system) to its light and temperature environment.

    PubMed

    Léchaudel, Mathieu; Lopez-Lauri, Félicie; Vidal, Véronique; Sallanon, Huguette; Joas, Jacques

    2013-04-15

    Depending on the position of the fruit in the tree, mango fruit may be exposed to high temperature and intense light conditions that may lead to metabolic and physiological disorders and affect yield and quality. The present study aimed to determine how mango fruit adapted its functioning in terms of fruit water relations, epicarp characteristics and the antioxidant defence system in peel, to environmental conditions. The effect of contrasted temperature and light conditions was evaluated under natural solar radiation and temperature by comparing well-exposed and shaded fruit at three stages of fruit development. The sun-exposed and shaded peels of the two sides of the well-exposed fruit were also compared. Depending on fruit position within the canopy and on the side of a well-exposed fruit, the temperature gradient over a day affected fruit characteristics such as transpiration, as revealed by the water potential gradient as a function of the treatments, and led to a significant decrease in water conductance for well-exposed fruits compared to fruits within the canopy. Changes in cuticle thickness according to fruit position were consistent with those of fruit water conductance. Osmotic potential was also affected by climatic environment and harvest stage. Environmental conditions that induced water stress and greater light exposure, like on the sunny side of well-exposed fruit, increased the hydrogen peroxide, malondialdehyde and total and reduced ascorbate contents, as well as SOD, APX and MDHAR activities, regardless of the maturity stage. The lowest values were measured in the peel of the shaded fruit, that of the shaded side of well-exposed fruit being intermediate. Mango fruits exposed to water-stress-induced conditions during growth adapt their functioning by reducing their transpiration. Moreover, oxidative stress was limited as a consequence of the increase in antioxidant content and enzyme activities. This adaptive response of mango fruit to its

  12. Response of the physiological parameters of mango fruit (transpiration, water relations and antioxidant system) to its light and temperature environment.

    PubMed

    Léchaudel, Mathieu; Lopez-Lauri, Félicie; Vidal, Véronique; Sallanon, Huguette; Joas, Jacques

    2013-04-15

    Depending on the position of the fruit in the tree, mango fruit may be exposed to high temperature and intense light conditions that may lead to metabolic and physiological disorders and affect yield and quality. The present study aimed to determine how mango fruit adapted its functioning in terms of fruit water relations, epicarp characteristics and the antioxidant defence system in peel, to environmental conditions. The effect of contrasted temperature and light conditions was evaluated under natural solar radiation and temperature by comparing well-exposed and shaded fruit at three stages of fruit development. The sun-exposed and shaded peels of the two sides of the well-exposed fruit were also compared. Depending on fruit position within the canopy and on the side of a well-exposed fruit, the temperature gradient over a day affected fruit characteristics such as transpiration, as revealed by the water potential gradient as a function of the treatments, and led to a significant decrease in water conductance for well-exposed fruits compared to fruits within the canopy. Changes in cuticle thickness according to fruit position were consistent with those of fruit water conductance. Osmotic potential was also affected by climatic environment and harvest stage. Environmental conditions that induced water stress and greater light exposure, like on the sunny side of well-exposed fruit, increased the hydrogen peroxide, malondialdehyde and total and reduced ascorbate contents, as well as SOD, APX and MDHAR activities, regardless of the maturity stage. The lowest values were measured in the peel of the shaded fruit, that of the shaded side of well-exposed fruit being intermediate. Mango fruits exposed to water-stress-induced conditions during growth adapt their functioning by reducing their transpiration. Moreover, oxidative stress was limited as a consequence of the increase in antioxidant content and enzyme activities. This adaptive response of mango fruit to its

  13. Genome duplication and the evolution of physiological responses to water stress.

    PubMed

    Maherali, Hafiz; Walden, Alison E; Husband, Brian C

    2009-11-01

    Whole-genome multiplication, or polyploidy, is common in angiosperms and many species consist of multiple cytotypes that have different physiological tolerances. However, the relative importance of genome duplication vs post-duplication evolutionary change in causing differentiation between cytotypes is not known. We examined the water relations of Chamerion angustifolium, a herbaceous perennial in which diploid and tetraploid cytotypes occupy different niches. To differentiate between the effects of genome duplication and evolutionary changes that followed polyploidization, we compared extant diploids and tetraploids with experimentally synthesized neotetraploids. Tetraploids had 32% higher xylem hydraulic conductivity (K(H)) than neotetraploids and 87% higher K(H) than diploids, but vulnerability to water stress induced cavitation and gas exchange sensitivity to water potential did not differ among cytotypes. Nevertheless, tetraploids took 22% and 30% longer to wilt than neotetraploids and diploids. A simple hydraulic model suggested that tetraploids deplete soil moisture to a greater degree than neotetraploids and diploids before reaching leaf water potentials that cause stomatal closure. We conclude that the different physiological tolerances and distribution of diploid and tetraploid C. angustifolium are unlikely to be caused solely by genome duplication. The enhanced ability of tetraploids to survive water stress likely evolved after polyploidization. PMID:19703115

  14. [Effects of intermittent irrigation on ecological and physiological water requirement of rice in north China].

    PubMed

    Wang, Xiaoying; Liang, Wenju; Wen, Dazhong

    2004-10-01

    The ecological and physiological water requirement of rice was studied in a paddy field of north China, and the field experiment was conducted at Shenyang Experimental Station of Ecology, Chinese Academy of Sciences. Under continuous flooding irrigation (CSF) and intermittent irrigation (IT) conditions, the evapotranspiration and soil evaporation of paddy fields were measured by non-weighing lysimeters and micro-lysimeters, respectively. The results showed that compared with continuous flooding irrigation, the transpiration under intermittent irrigation condition was not significantly reduced, but 16% and 24% of water amounts were reduced by decreasing the water losses through soil water evaporation and percolation, respectively. The water use efficiency of intermittent irrigation was increased 10%, without any adverse effects on biomass and grain yield of rice. Although the amount of water requirement under IT treatment was reduced significantly compared with CSF treatment, about 60% of total water requirement was still lost through deep percolation. Based on the results obtained, the corresponding countermeasures to reduce the amounts of soil water evaporation and percolation and to increase the water use efficiency were put forward in this paper. PMID:15624834

  15. Effects of salt stress on eco-physiological characteristics in Robinia pseudoacacia based on salt-soil rhizosphere.

    PubMed

    Mao, Peili; Zhang, Yujuan; Cao, Banghua; Guo, Longmei; Shao, Hongbo; Cao, Zhenyu; Jiang, Qiankun; Wang, Xuan

    2016-10-15

    Robinia pseudoacacia is the main arbor species in the coastal saline-alkali area of the Yellow River Delta. Because most studies focus on the aboveground parts, detailed information regarding root functioning under salinity is scare. Root traits of seedlings of R. pseudoacacia including morphological, physiological and growth properties under four salinity levels (CK, 1‰, 3‰ and 5‰ NaCl) were studied by the pot experiments to better understand their functions and relationships with the shoots. The results showed that seedling biomass decreased by the reduction of root, stem and leaf biomass with the increase of salinity levels. With increasing salinity levels, total root length (TRL) and total root surface area (TRSA) decreased, whereas specific root length (SRL) and specific root area (SRA) increased. Salt stress decreased root activity (RA) and the maximum net photosynthetic rate (Amax) and increased the water saturation deficit (WSD) significantly in the body. Correlation analyses showed significantly correlations between root morphological and physiological parameters and seedling biomass and shoot physiological indexes. R. pseudoacacia seedlings could adapt to 1‰ salinity by regulating the root morphology and physiology, but failed in 5‰ salinity. How to adjust the water status in the body with decreasing water uptake by roots was an important way for R. pseudoacacia seedlings to adapt to the salt stress.

  16. Effects of salt stress on eco-physiological characteristics in Robinia pseudoacacia based on salt-soil rhizosphere.

    PubMed

    Mao, Peili; Zhang, Yujuan; Cao, Banghua; Guo, Longmei; Shao, Hongbo; Cao, Zhenyu; Jiang, Qiankun; Wang, Xuan

    2016-10-15

    Robinia pseudoacacia is the main arbor species in the coastal saline-alkali area of the Yellow River Delta. Because most studies focus on the aboveground parts, detailed information regarding root functioning under salinity is scare. Root traits of seedlings of R. pseudoacacia including morphological, physiological and growth properties under four salinity levels (CK, 1‰, 3‰ and 5‰ NaCl) were studied by the pot experiments to better understand their functions and relationships with the shoots. The results showed that seedling biomass decreased by the reduction of root, stem and leaf biomass with the increase of salinity levels. With increasing salinity levels, total root length (TRL) and total root surface area (TRSA) decreased, whereas specific root length (SRL) and specific root area (SRA) increased. Salt stress decreased root activity (RA) and the maximum net photosynthetic rate (Amax) and increased the water saturation deficit (WSD) significantly in the body. Correlation analyses showed significantly correlations between root morphological and physiological parameters and seedling biomass and shoot physiological indexes. R. pseudoacacia seedlings could adapt to 1‰ salinity by regulating the root morphology and physiology, but failed in 5‰ salinity. How to adjust the water status in the body with decreasing water uptake by roots was an important way for R. pseudoacacia seedlings to adapt to the salt stress. PMID:27289394

  17. Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts

    USGS Publications Warehouse

    Liebich, T.; McCormick, S.D.; Kircheis, D.; Johnson, K.; Regal, R.; Hrabik, T.

    2011-01-01

    The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na+- and K+-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream pH between 5??6 and 5??8 during the study period. The findings from this study suggest that physiological effects on S. salar smolts are strongly correlated with stream pH and that in rivers and streams with low dissolved organic carbon (DOC) concentrations the threshold for physiological effects and mortality probably occurs at a higher pH and shorter exposure period than in rivers with higher DOC. Additionally, whenever an acidification event in which pH drops below 5??9 coincides with S. salar smolt migration in eastern Maine rivers, there is potential for a significant reduction in plasma ions of S. salar smolts. ?? 2011 The Fisheries Society of the British Isles.

  18. Water chemistry and its effects on the physiology and survival of Atlantic salmon Salmo salar smolts.

    PubMed

    Liebich, T; McCormick, S D; Kircheis, D; Johnson, K; Regal, R; Hrabik, T

    2011-08-01

    The physiological effects of episodic pH fluctuations on Atlantic salmon Salmo salar smolts in eastern Maine, U.S.A., were investigated. During this study, S. salar smolts were exposed to ambient stream-water chemistry conditions at nine sites in four catchments for 3 and 6 day intervals during the spring S. salar smolt migration period. Plasma chloride, plasma glucose, gill aluminium and gill Na(+)- and K(+)-ATPase levels in S. salar smolts were assessed in relation to ambient stream-water chemistry during this migration period. Changes in both plasma chloride and plasma glucose levels of S. salar smolts were strongly correlated with stream pH, and S. salar smolt mortality occurred in one study site with ambient stream pH between 5·6 and 5·8 during the study period. The findings from this study suggest that physiological effects on S. salar smolts are strongly correlated with stream pH and that in rivers and streams with low dissolved organic carbon (DOC) concentrations the threshold for physiological effects and mortality probably occurs at a higher pH and shorter exposure period than in rivers with higher DOC. Additionally, whenever an acidification event in which pH drops below 5·9 coincides with S. salar smolt migration in eastern Maine rivers, there is potential for a significant reduction in plasma ions of S. salar smolts.

  19. Effects of abiotic stress on physiological plasticity and water use of Setaria viridis (L.).

    PubMed

    Saha, Prasenjit; Sade, Nir; Arzani, Ahmad; Rubio Wilhelmi, Maria Del Mar; Coe, Kevin M; Li, Bosheng; Blumwald, Eduardo

    2016-10-01

    The emerging model Setaria viridis with its C4 photosynthesis and adaptation to hot and dry locations is a promising system to investigate water use and abiotic stress tolerance. We investigated the physiological plasticity of six S. viridis natural accessions that originated from different regions of the world under normal conditions and conditions of water-deficit stress and high temperatures. Accessions Zha-1, A10.1 and Ula-1 showed significantly higher leaf water potential (Ψleaf), photosynthesis (A), transpiration (E), and stomatal conductance (gs) rates compared to Ast-1, Aba-1 and Sha-1 when grown under stress conditions. Expression analysis of genes associated with C4 photosynthesis, aquaporins, ABA biosynthesis and signaling including genes involved in stress revealed an increased sensitivity of Ast-1, Aba-1 and Sha-1 to stresses. Correlation analysis of gene expression data with physiological and biochemical changes characterized A10.1 and Ast-1 as two extreme tolerant and sensitive accessions originated from United States and Azerbaijan under water-deficit and heat stress, respectively. Although preliminary, our study demonstrated the plasticity of S. viridis accessions under stress, and allows the identification of tolerant and sensitive accessions that could be use to study the mechanisms associated with stress tolerance and to characterize of the regulatory networks involved in C4 grasses. PMID:27593471

  20. Lead tolerance of water hyacinth (Eichhornia crassipes Mart. - Pontederiaceae) as defined by anatomical and physiological traits.

    PubMed

    Pereira, Fabricio J; Castro, Evaristo M de; Oliveira, Cynthia de; Pires, Marinês F; Pereira, Marcio P; Ramos, Silvio J; Faquin, Valdemar

    2014-09-01

    This study aimed at verifying the lead tolerance of water hyacinth and at looking at consequent anatomical and physiological modifications. Water hyacinth plants were grown on nutrient solutions with five different lead concentrations: 0.00, 0.50, 1.00, 2.00 and 4.00 mg L-1 by 20 days. Photosynthesis, transpiration, stomatal conductance and the Ci/Ca rate were measured at the end of 15 days of experiment. At the end of the experiment, the anatomical modifications in the roots and leaves, and the activity of antioxidant system enzymes, were evaluated. Photosynthetic and Ci/Ca rates were both increased under all lead treatments. Leaf anatomy did not exhibit any evidence of toxicity effects, but showed modifications of the stomata and in the thickness of the palisade and spongy parenchyma in the presence of lead. Likewise, root anatomy did not exhibit any toxicity effects, but the xylem and phloem exhibited favorable modifications as well as increased apoplastic barriers. All antioxidant system enzymes exhibited increased activity in the leaves, and some modifications in roots, in the presence of lead. It is likely, therefore, that water hyacinth tolerance to lead is related to anatomical and physiological modifications such as increased photosynthesis and enhanced anatomical capacity for CO2 assimilation and water conductance.

  1. Distribution, phylogenetic diversity and physiological characteristics of epsilon-Proteobacteria in a deep-sea hydrothermal field.

    PubMed

    Nakagawa, Satoshi; Takai, Ken; Inagaki, Fumio; Hirayama, Hisako; Nunoura, Takuro; Horikoshi, Koki; Sako, Yoshihiko

    2005-10-01

    Epsilon-Proteobacteria is increasingly recognized as an ecologically significant group of bacteria, particularly in deep-sea hydrothermal environments. In this study, we studied the spatial distribution, diversity and physiological characteristics of the epsilon-Proteobacteria in various microbial habitats in the vicinity of a deep-sea hydrothermal vent occurring in the Iheya North field in the Mid-Okinawa Trough, by using culture-dependent and -independent approaches. The habitats studied were inside and outside hydrothermal plume, and annelid polychaete tubes. In addition, we deployed colonization devices near the vent emission. The polychaete tubes harboured physiologically and phylogenetically diverse microbial community. The in situ samplers were predominantly colonized by epsilon-Proteobacteria. Energy metabolism of epsilon-Proteobacteria isolates was highly versatile. Tree topology generated from the metabolic traits was significantly different (P = 0.000) from that of 16S rRNA tree, indicating current 16S rRNA gene-based analyses do not provide sufficient information to infer the physiological characteristics of epsilon-Proteobacteria. Nevertheless, culturability of epsilon-Proteobacteria in various microbial habitats differed among the phylogenetic subgroups. Members of Sulfurimonas were characterized by the robust culturability, and the other phylogenetic subgroups appeared to lose culturability in seawater, probably because of the sensitivity to oxygen. These results provide new insight into the ecophysiological characteristics of the deep-sea hydrothermal vent epsilon-Proteobacteria, which has never been assessed by comparative analysis of the 16S rRNA genes.

  2. Physiological responses in swine treated with water containing sodium bicarbonate as a prophylactic for gastric ulcers.

    PubMed

    Cole, J T; Argenzio, R A; Eisemann, J H

    2004-09-01

    Maintenance of gastric pH above 4.0 aids the prevention of bile acid-mediated ulcerative damage to the pars esophageal tissue in pigs. One means of doing so is the addition of buffering compounds, such as sodium bicarbonate, to the water supply; however, any potential physiological effect of buffer consumption has yet to be determined. Experiment 1 tested the acute effects of buffer addition to the water supply on systemic acid-base and electrolyte balance in swine (BW 40.7 +/- 3.0 kg). Consumption of water calculated to a 200 mOsm solution with sodium bicarbonate for 24 h increased (P < 0.05) blood Na+, HCO3(-), and pCO2, although these effects were all within physiologically tolerable levels. Urine pH and Na+ excretion increased (P < 0.001) following the consumption of NaHCO3, with Na+ concentration almost threefold higher in treated pigs compared with controls. Experiment 2 determined the chronic systemic effects of buffer consumption by measuring blood and urine variables, with pigs consuming NaHCO3-treated water throughout. Water consumption increased (P < 0.001) during buffer consumption, although intake levels remained within normal ranges. Blood pH levels were not affected by long-term consumption of dietary buffer; however, blood HCO3(-) (P < 0.05), Na+, and pCO2 (P < 0.01) increased. Urine pH and urine Na+ concentration increased (P < 0.01) in buffer-treated compared with control animals. Results indicate that sodium bicarbonate can safely be added to the water supply for pigs, with no clinically relevant alterations in acid-base balance because the animals readily compensate for buffer intake.

  3. [Physiological and biochemical characteristics of the cells of a carrot gall tumor developing in weightlessness].

    PubMed

    Tairbekov, M G; Voronkov, L A; Guzhova, N A

    1982-01-01

    The paper presents the results of experiments with the carrot tissues infected with Agrobacterium tumefaciens flown onboard the biosatellite Cosmos-1129 in cooperation with the US scientists. Postflight, the respiratory activity of tumour cells was determined and K+ and Na+ permeability of cell membranes was measured. The resulting data give evidence that in weightlessness the development of the carrot gall tumour is accompanied by changes in the above physiological and biochemical parameters. The changes are, however, within the physiological limits, leading to no pathologies of the whole cell.

  4. Eco-Physiological Responses of Dominant Species to Watering in a Natural Grassland Community on the Semi-Arid Loess Plateau of China.

    PubMed

    Niu, Furong; Duan, Dongping; Chen, Ji; Xiong, Peifeng; Zhang, He; Wang, Zhi; Xu, Bingcheng

    2016-01-01

    Altered precipitation regimes significantly affect ecosystem structure and function in arid and semi-arid regions. In order to investigate effects of precipitation changes on natural grassland community in the semi-arid Loess Plateau, the current research examined eco-physiological characteristics of two co-dominant species (i.e., Bothriochloa ischaemum and Lespedeza davurica) and community composition following two watering instances (i.e., precipitation pulses, July and August, 2011, respectively) in a natural grassland community. Results showed that the photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO2 concentration rapidly increased on the first to third day following watering in both species, and both months. Under watering treatments, the maximum net photosynthetic rates appeared on the second to third day after watering, which increased 30-80% in B. ischaemum and 40-50% in L. davurica compared with non-watering treatments, respectively. Leaf water use efficiency kept stable or initially decreased in both species under watering treatments. Watering in July produced more promoting effects on grass photosynthesis than in August, particularly in B. ischaemum. Community above-ground biomass at the end of the growing season increased after watering, although no significant changes in species diversity were observed. Our results indicated that timing and magnitude of watering could significantly affect plant eco-physiological processes, and there were species-specific responses in B. ischaemum and L. davurica. Pulsed watering increased community productivity, while did not significantly alter community composition after one growing season. The outcomes of this study highlight eco-physiological traits in dominant species may playing important roles in reshaping community composition under altered precipitation regimes. PMID:27242864

  5. Eco-Physiological Responses of Dominant Species to Watering in a Natural Grassland Community on the Semi-Arid Loess Plateau of China

    PubMed Central

    Niu, Furong; Duan, Dongping; Chen, Ji; Xiong, Peifeng; Zhang, He; Wang, Zhi; Xu, Bingcheng

    2016-01-01

    Altered precipitation regimes significantly affect ecosystem structure and function in arid and semi-arid regions. In order to investigate effects of precipitation changes on natural grassland community in the semi-arid Loess Plateau, the current research examined eco-physiological characteristics of two co-dominant species (i.e., Bothriochloa ischaemum and Lespedeza davurica) and community composition following two watering instances (i.e., precipitation pulses, July and August, 2011, respectively) in a natural grassland community. Results showed that the photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO2 concentration rapidly increased on the first to third day following watering in both species, and both months. Under watering treatments, the maximum net photosynthetic rates appeared on the second to third day after watering, which increased 30–80% in B. ischaemum and 40–50% in L. davurica compared with non-watering treatments, respectively. Leaf water use efficiency kept stable or initially decreased in both species under watering treatments. Watering in July produced more promoting effects on grass photosynthesis than in August, particularly in B. ischaemum. Community above-ground biomass at the end of the growing season increased after watering, although no significant changes in species diversity were observed. Our results indicated that timing and magnitude of watering could significantly affect plant eco-physiological processes, and there were species-specific responses in B. ischaemum and L. davurica. Pulsed watering increased community productivity, while did not significantly alter community composition after one growing season. The outcomes of this study highlight eco-physiological traits in dominant species may playing important roles in reshaping community composition under altered precipitation regimes. PMID:27242864

  6. Eco-Physiological Responses of Dominant Species to Watering in a Natural Grassland Community on the Semi-Arid Loess Plateau of China.

    PubMed

    Niu, Furong; Duan, Dongping; Chen, Ji; Xiong, Peifeng; Zhang, He; Wang, Zhi; Xu, Bingcheng

    2016-01-01

    Altered precipitation regimes significantly affect ecosystem structure and function in arid and semi-arid regions. In order to investigate effects of precipitation changes on natural grassland community in the semi-arid Loess Plateau, the current research examined eco-physiological characteristics of two co-dominant species (i.e., Bothriochloa ischaemum and Lespedeza davurica) and community composition following two watering instances (i.e., precipitation pulses, July and August, 2011, respectively) in a natural grassland community. Results showed that the photosynthetic rate, transpiration rate, stomatal conductance and intercellular CO2 concentration rapidly increased on the first to third day following watering in both species, and both months. Under watering treatments, the maximum net photosynthetic rates appeared on the second to third day after watering, which increased 30-80% in B. ischaemum and 40-50% in L. davurica compared with non-watering treatments, respectively. Leaf water use efficiency kept stable or initially decreased in both species under watering treatments. Watering in July produced more promoting effects on grass photosynthesis than in August, particularly in B. ischaemum. Community above-ground biomass at the end of the growing season increased after watering, although no significant changes in species diversity were observed. Our results indicated that timing and magnitude of watering could significantly affect plant eco-physiological processes, and there were species-specific responses in B. ischaemum and L. davurica. Pulsed watering increased community productivity, while did not significantly alter community composition after one growing season. The outcomes of this study highlight eco-physiological traits in dominant species may playing important roles in reshaping community composition under altered precipitation regimes.

  7. Comparative morpho-physiological and biochemical responses of lentil and grass pea genotypes under water stress

    PubMed Central

    Talukdar, Dibyendu

    2013-01-01

    Background: Both lentil (Lens culinaris Medik.) and grass pea (Lathyrus sativus L.) in the family Fabaceae are two important cool-season food legumes, often experiencing water stress conditions during growth and maturity. Objective: The present study was undertaken to ascertain the response of these two crops under different water stress regimes. Materials and Methods: Different morpho-physiological and biochemical parameters were studied in a pot experiment under controlled environmental conditions. Along with control (proper irrigation, 0 stress), three sets of plants were subjected to mild (6 d), moderate (13 d) and severe (20 d) water stress by withholding irrigation at the appropriate time. Results: Compared with control, plant growth traits and seed yield components reduced significantly in both crops with increasing period of water stress, resulting in lowering of dry mass with more severe effect on lentil compared with grass pea. Foliar Relative Water Content (RWC) (%), K+/Na+ ratio, chlorophyll (chl) a, chl a/b ratio, stomatal conductance and net photosynthetic rate declined considerably in both crops under water stress. Leaf-free proline level increased significantly in both crops, but it decreased markedly in nodules of lentil and remained unchanged in grass pea. Nodulation was also affected due to water stress. The impairment in growth traits and physio-biochemical parameters under water stress was manifested in reduction of drought tolerance efficiency of both crops. Conclusion: Impact of water stress was more severe on lentil compared with grass pea, and modulation of growth traits signified necessity of a detailed strategy in breeding of food legumes under water stress. PMID:24082740

  8. Rootstock alleviates PEG-induced water stress in grafted pepper seedlings: physiological responses.

    PubMed

    Penella, Consuelo; Nebauer, Sergio G; Bautista, Alberto San; López-Galarza, Salvador; Calatayud, Ángeles

    2014-06-15

    Recent studies have shown that tolerance to abiotic stress, including water stress, is improved by grafting. In a previous work, we took advantage of the natural variability of Capsicum spp. and selected accessions tolerant and sensitive to water stress as rootstocks. The behavior of commercial cultivar 'Verset' seedlings grafted onto the selected rootstocks at two levels of water stress provoked by adding 3.5 and 7% PEG (polyethylene glycol) was examined over 14 days. The objective was to identify the physiological traits responsible for the tolerance provided by the rootstock in order to determine if the tolerance is based on the maintenance of the water relations under water stress or through the activation of protective mechanisms. To achieve this goal, various physiological parameters were measured, including: water relations; proline accumulation; gas exchange; chlorophyll fluorescence; nitrate reductase activity; and antioxidant capacity. Our results indicate that the effect of water stress on the measured parameters depends on the duration and intensity of the stress level, as well as the rootstock used. Under control conditions (0% PEG) all plant combinations showed similar values for all measured parameters. In general terms, PEG provoked a strong decrease in the gas exchange parameters in the cultivar grafted onto the sensitive accessions, as also observed in the ungrafted plants. This effect was related to lower relative water content in the plants, provoked by an inefficient osmotic adjustment that was dependent on reduced proline accumulation. At the end of the experiment, chronic photoinhibition was observed in these plants. However, the plants grafted onto the tolerant rootstocks, despite the reduction in photosynthetic rate, maintained the protective capacity of the photosynthetic machinery mediated by osmotic adjustment (based on higher proline content). In addition, water stress limited uptake and further NO3(-) transfer to the leaves. Increased

  9. Spectral reflectance and radiance characteristics of water pollutants

    NASA Technical Reports Server (NTRS)

    Wezernak, C. T.; Turner, R. E.; Lyzenga, D. R.

    1976-01-01

    Spectral reflectance characteristics of water pollutants and water bodies were compiled using the existing literature. Radiance calculations were performed at satellite altitude for selected illumination angles and atmospheric conditions. The work described in this report was limited to the reflective portion of the spectrum between 0.40 micrometer to 1.0 micrometer.

  10. Anthropomorphic breast phantoms with physiological water, lipid, and hemoglobin content for near-infrared spectral tomography

    PubMed Central

    Michaelsen, Kelly E.; Krishnaswamy, Venkataramanan; Shenoy, Adele; Jordan, Emily; Pogue, Brian W.; Paulsen, Keith D.

    2014-01-01

    Abstract. Breast mimicking tissue optical phantoms with sufficient structural integrity to be deployed as stand-alone imaging targets are developed and successfully constructed with biologically relevant concentrations of water, lipid, and blood. The results show excellent material homogeneity and reproducibility with inter- and intraphantom variability of 3.5 and 3.8%, respectively, for water and lipid concentrations ranging from 15 to 85%. The phantoms were long-lasting and exhibited water and lipid fractions that were consistent to within 5% of their original content when measured 2 weeks after creation. A breast-shaped three-compartment model of adipose, fibroglandular, and malignant tissues was created with water content ranging from 30% for the adipose simulant to 80% for the tumor. Mean measured water content ranged from 30% in simulated adipose to 73% in simulated tumor with the higher water localized to the tumor-like material. This novel heterogeneous phantom design is composed of physiologically relevant concentrations of the major optical absorbers in the breast in the near-infrared wavelengths that should significantly improve imaging system characterization and optimization because the materials have stand-alone structural integrity and can be readily molded into the sizes and shapes of tissues commensurate with clinical breast imaging. PMID:24549438

  11. Characteristics of water infiltration in layered water repellent soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydrophobic soil can influence soil water infiltration, but information regarding the impacts of different levels of hydrophobicity within a layered soil profile is limited. An infiltration study was conducted to determine the effects of different levels of hydrophobicity and the position of the hyd...

  12. [Impacts of algal blooms accumulation on physiological ecology of water hyacinth].

    PubMed

    Wu, Ting-ting; Liu, Guo-feng; Han, Shi-qun; Zhou, Qing; Tang, Wan-ying

    2015-01-01

    Blue-green algae bloom will consume plenty of dissolved oxygen in water, which affects the growth of aquatic plants. The effects of water hyacinth growth and physiological response changes under 25 degrees C, 5 different concentrations of cyanobacteria gathered were studied and which would provide a theoretical basis to mitigate adverse impacts and improve water purification effect. The results showed that water quality indexes including dissolved oxygen (DO), pH dropped in algae density below 60 g x L(-1), with the increase of algae density. And the level of oxidation-reduction potential dropped to about 100 mV. The removal rates of TN, TP and COD were 58%-78%, 43%-68% and 59%-73%, leaf soluble protein, soluble sugar, MDA contents increased, respectively; and the MDA content became higher with the increase of algae density. It indicated that the water hyacinth could adapt to the adversity condition as algae density less than 60 g x L(-1). While algae density above 60 g x L(-1), water quality indexes significantly decreased, respectively and the water was in hypoxia or anoxia conditions. Plant leaves soluble sugar contents had a change trend of low-high-low. It indicated that the removal rates of TN, TP decreased with the increase of algae density and water hyacinth had irreversible stress. Plant root length, total length, fresh weight in different treatments, increased compared with the beginning of the experiment, the increase of root length, total length and fresh weight were 0.29-2.44 times, 0.41-0.76 times and 0.9-1.43 times. The increase of root length, total length decreased with the increase of algae density. According to the results, the cyanobacteria should avoid of excessive accumulation as using the floating plant to purify the water.

  13. [Impacts of algal blooms accumulation on physiological ecology of water hyacinth].

    PubMed

    Wu, Ting-ting; Liu, Guo-feng; Han, Shi-qun; Zhou, Qing; Tang, Wan-ying

    2015-01-01

    Blue-green algae bloom will consume plenty of dissolved oxygen in water, which affects the growth of aquatic plants. The effects of water hyacinth growth and physiological response changes under 25 degrees C, 5 different concentrations of cyanobacteria gathered were studied and which would provide a theoretical basis to mitigate adverse impacts and improve water purification effect. The results showed that water quality indexes including dissolved oxygen (DO), pH dropped in algae density below 60 g x L(-1), with the increase of algae density. And the level of oxidation-reduction potential dropped to about 100 mV. The removal rates of TN, TP and COD were 58%-78%, 43%-68% and 59%-73%, leaf soluble protein, soluble sugar, MDA contents increased, respectively; and the MDA content became higher with the increase of algae density. It indicated that the water hyacinth could adapt to the adversity condition as algae density less than 60 g x L(-1). While algae density above 60 g x L(-1), water quality indexes significantly decreased, respectively and the water was in hypoxia or anoxia conditions. Plant leaves soluble sugar contents had a change trend of low-high-low. It indicated that the removal rates of TN, TP decreased with the increase of algae density and water hyacinth had irreversible stress. Plant root length, total length, fresh weight in different treatments, increased compared with the beginning of the experiment, the increase of root length, total length and fresh weight were 0.29-2.44 times, 0.41-0.76 times and 0.9-1.43 times. The increase of root length, total length decreased with the increase of algae density. According to the results, the cyanobacteria should avoid of excessive accumulation as using the floating plant to purify the water. PMID:25898654

  14. Nonlinear Dynamic Characteristics of Oil-in-Water Emulsions

    NASA Astrophysics Data System (ADS)

    Yin, Zhaoqi; Han, Yunfeng; Ren, Yingyu; Yang, Qiuyi; Jin, Ningde

    2016-08-01

    In this article, the nonlinear dynamic characteristics of oil-in-water emulsions under the addition of surfactant were experimentally investigated. Firstly, based on the vertical upward oil-water two-phase flow experiment in 20 mm inner diameter (ID) testing pipe, dynamic response signals of oil-in-water emulsions were recorded using vertical multiple electrode array (VMEA) sensor. Afterwards, the recurrence plot (RP) algorithm and multi-scale weighted complexity entropy causality plane (MS-WCECP) were employed to analyse the nonlinear characteristics of the signals. The results show that the certainty is decreasing and the randomness is increasing with the increment of surfactant concentration. This article provides a novel method for revealing the nonlinear dynamic characteristics, complexity, and randomness of oil-in-water emulsions with experimental measurement signals.

  15. Twenty-Four-Hour Urine Osmolality as a Physiological Index of Adequate Water Intake

    PubMed Central

    Perrier, Erica T.; Buendia-Jimenez, Inmaculada; Vecchio, Mariacristina; Armstrong, Lawrence E.; Tack, Ivan; Klein, Alexis

    2015-01-01

    While associations exist between water, hydration, and disease risk, research quantifying the dose-response effect of water on health is limited. Thus, the water intake necessary to maintain optimal hydration from a physiological and health standpoint remains unclear. The aim of this analysis was to derive a 24 h urine osmolality (UOsm) threshold that would provide an index of “optimal hydration,” sufficient to compensate water losses and also be biologically significant relative to the risk of disease. Ninety-five adults (31.5 ± 4.3 years, 23.2 ± 2.7 kg·m−2) collected 24 h urine, provided morning blood samples, and completed food and fluid intake diaries over 3 consecutive weekdays. A UOsm threshold was derived using 3 approaches, taking into account European dietary reference values for water; total fluid intake, and urine volumes associated with reduced risk for lithiasis and chronic kidney disease and plasma vasopressin concentration. The aggregate of these approaches suggest that a 24 h urine osmolality ≤500 mOsm·kg−1 may be a simple indicator of optimal hydration, representing a total daily fluid intake adequate to compensate for daily losses, ensure urinary output sufficient to reduce the risk of urolithiasis and renal function decline, and avoid elevated plasma vasopressin concentrations mediating the increased antidiuretic effort. PMID:25866433

  16. Aquaporin water channels in the mammary gland: from physiology to pathophysiology and neoplasia.

    PubMed

    Mobasheri, Ali; Barrett-Jolley, Richard

    2014-03-01

    Aquaporins are membrane proteins that play fundamental roles in water and small solute transport across epithelial and endothelial barriers. Recent studies suggest that several aquaporin proteins are present in the mammary gland. Immunohistochemical techniques have confirmed the presence of aquaporin 1 (AQP1) and AQP3 water channels in rat, mouse, bovine and human mammary glands. Studies suggest that in addition to AQP1 and AQP3 AQP4, AQP5 and AQP7 proteins are expressed in different locations in the mammary gland. Aquaporins play key roles in tumor biology and are involved in cell growth, migration and formation of ascites via increased water permeability of micro-vessels. Emerging evidence suggests that expression of these proteins is altered in mammary tumors and in breast cancer cell lines although it is not yet clear whether this is a cause or a consequence of neoplastic development. This review analyzes the expression and potential functional roles of aquaporin water channels in the mammary gland. The physiological mechanisms involved in the transport of water and small solutes across mammary endothelial and epithelial barriers are discussed in the context of milk production and lactation. This paper also reviews papers from the recent cancer literature that implicate aquaporins in mammary neoplasia.

  17. Pros and Cons of Using Water Immersion to Simulate Physiological Responses to Microgravity

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Tomko, David L. (Technical Monitor)

    1995-01-01

    Head-out water immersion (HOI) has been employed as a remedial treatment for various ills and ailments for many millennia, and total body immersion even longer as protective encapsulation for the mammalian fetus. Two discrete differences between stimuli induced by true microgravity (10(exp -4) g) and HOI are readily apparent. External water pressure on the skin and accompanying negative pressure breathing cause blood to shift headward. Secondly, the gravitational force is ever present during immersion and microgravity, but its effect is essentially neutralized during Earth orbital flight. Thus, the physiological responses to immersion should not be expected to match those during microgravity. Immersion has been used mainly to study and understand kidney function and associated cardiovascular responses for control of body fluid volume and osmotic content, with some application to and simulation of microgravity responses. There is a plethora of data from human HOI studies, but relatively few controlled data from microgravity studies. In general, it appears that physiological responses occur more quickly with water immersion than in microgravity, but this may be due to less rigorous control (voluntary and involuntary) of the preflight state of crew members. The central venous pressure-vasopressin (Gauer-Henry) reflex control for fluid balance may not be of prime importance in microgravity. Gross functions such as reduced body weight and water, level of hypovolemia, decreased isokinetic strength, and lower nitrogen balance found during immersion are qualitatively similar in microgravity, but the mechanisms controlling these and other functions are, for the most part, unclear. Only acquisition of data from well-controlled microgravity experiments will resolve this discrepancy.

  18. [Effects of grafting on physiological characteristics of melon (Cucumis melo) seedlings under copper stress].

    PubMed

    Tan, Ming-min; Zhang, Xin-ying; Fu, Qiu-shi; He, Zhong-qun; Wang, Huai-song

    2014-12-01

    The effects of grafting on physiological characters of melon (Cucumis melo) seedlings under copper stress were investigated with Pumpkin Jingxinzhen No. 3 as stock and oriental melon IVF09 as scion. The results showed that the physiological characters of melon seedlings were inhibited significantly under copper stress. Compared with self-rooted seedlings, the biomass, the contents of photosynthetic pigment, glucose and fructose, the photosynthetic parameters, the activities of sucrose phosphate synthase, neutral invertase and acid invertase in the leaves of the grafted seedlings were increased significantly. The uptake of nutrients was improved with the contents of K, P, Na increased and the content of Cu decreased. When the concentration of Cu2+ stress was 800 micromol L(-1), the contents of Cu in the leaves and roots of the grafted seedlings were decreased by 31.3% and 15.2%, respectively. Endogenous hormone balance of seedlings was improved by grafting. In the grafted seedlings, the content of IAA and peroxidase activity were higher, whereas the contents of ABA, maleicdialdehyde, the activities of superoxide dismutase and catalase were lower than that in the control. It was concluded that the copper stress on the physiological characters of melon seedlings was relieved by grafting which improved the resistance of the grafted seedlings. PMID:25876409

  19. Numerical Simulation of Air Bubble Characteristics in Stationary Water

    NASA Astrophysics Data System (ADS)

    Zhang, C. X.; Wang, Y. X.

    The motion of air bubble in water plays a key role in such diverse aspects as air bubble curtain breakwater, air curtain drag reduction, air cushion isolation, weakening the shock wave in water by air bubble screen, etc. At present, the research on air bubble behaviors can be subdivided into several processes: air bubble formation from submerged orifices; interaction and coalescence during the ascending. The work presented in this paper focuses on numerical simulation of air bubble characteristics in stationary water, for example, air bubble formation, the ascending speed, the departing period, and so on. A series of models to simulate the characteristics of air bubble are developed by the VOF method in the two phase flow module of FLUENT. The numerical simulation results are consistent with the theoretical characteristics of air bubble in many aspects. So it is concluded that numerical simulation of air bubble characteristics in stationary water based on FLUENT is feasible. Due to the fact that the characteristics of air bubble are complicated questions, it is important that study on the air bubble behaviors in stationary water should be conducted on deeply.

  20. Patterns of water use and the tissue water relations in the dioecious shrub, Salix arctica: the physiological basis for habitat partitioning between the sexes.

    PubMed

    Dawson, T E; Bliss, L C

    1989-05-01

    Within the high arctic of Canada, Salix arctica, a dioecious, dwarf willow exhibits significant spatial segregation of the sexes. The overall sex ratio is female-biased and female plants are especially common in wet, higher nutrient, but lower soil temperature habitats. In contrast, male plants predominate in more xeric and lower nutrient habitats with higher soil temperatures that can be drought prone. Associated with the sex-specific habitat differences were differences in the seasonal and diurnal patterns of water use as measured by stomatal conductance to water vapor and the bulk tissue water relations of each gender. Within the wet habitats, female plants maintained higher rates of stomatal conductance (g) than males when soil and root temperatures were low (<4° C). In contrast, within the xeric habitats, male plants maintained higher g and had lower leaf water potentials Ψleaf at low soil water potentials and a high leaf-to-air vapor pressure gradient (Δw) when compared to females. Female plants had more positive carbon isotope ratios than males indicating a lower internal leaf carbon dioxide concentration and possibly higher water use efficiency relative to males. Tissue osmotic and elastic properties also differed between the sexes. Male plants demonstrated lower tissue osmotic potentials near full tissue hydration and at the turgor loss point and a lower bulk tissue elastic modulus (higher tissue elasticity) than female plants. Males also demonstrated a greater ability to osmotically adjust on a diurnal basis than females. These properties allowed male plants to maintain higher tissue turgor pressures at lower tissue water contents and Ψsoil over the course of the day. The sex-specific distributional and ecophysiological characteristics were also correlated with greater total plant growth and higher fecundity of females in wet habitats, and males in xeric habitats respectively. The intersexual differences in physiology persisted in all habitats. These

  1. Water sensor ppk28 modulates Drosophila lifespan and physiology through AKH signaling

    PubMed Central

    Waterson, Michael J.; Chung, Brian Y.; Harvanek, Zachary M.; Ostojic, Ivan; Alcedo, Joy; Pletcher, Scott D.

    2014-01-01

    Sensory perception modulates lifespan across taxa, presumably due to alterations in physiological homeostasis after central nervous system integration. The coordinating circuitry of this control, however, remains unknown. Here, we used the Drosophila melanogaster gustatory system to dissect one component of sensory regulation of aging. We found that loss of the critical water sensor, pickpocket 28 (ppk28), altered metabolic homeostasis to promote internal lipid and water stores and extended healthy lifespan. Additionally, loss of ppk28 increased neuronal glucagon-like adipokinetic hormone (AKH) signaling, and the AKH receptor was necessary for ppk28 mutant effects. Furthermore, activation of AKH-producing cells alone was sufficient to enhance longevity, suggesting that a perceived lack of water availability triggers a metabolic shift that promotes the production of metabolic water and increases lifespan via AKH signaling. This work provides an example of how discrete gustatory signals recruit nutrient-dependent endocrine systems to coordinate metabolic homeostasis, thereby influencing long-term health and aging. PMID:24821805

  2. Plant physiological models of heat, water and photoinhibition stress for climate change modelling and agricultural prediction

    NASA Astrophysics Data System (ADS)

    Nicolas, B.; Gilbert, M. E.; Paw U, K. T.

    2015-12-01

    Soil-Vegetation-Atmosphere Transfer (SVAT) models are based upon well understood steady state photosynthetic physiology - the Farquhar-von Caemmerer-Berry model (FvCB). However, representations of physiological stress and damage have not been successfully integrated into SVAT models. Generally, it has been assumed that plants will strive to conserve water at higher temperatures by reducing stomatal conductance or adjusting osmotic balance, until potentially damaging temperatures and the need for evaporative cooling become more important than water conservation. A key point is that damage is the result of combined stresses: drought leads to stomatal closure, less evaporative cooling, high leaf temperature, less photosynthetic dissipation of absorbed energy, all coupled with high light (photosynthetic photon flux density; PPFD). This leads to excess absorbed energy by Photosystem II (PSII) and results in photoinhibition and damage, neither are included in SVAT models. Current representations of photoinhibition are treated as a function of PPFD, not as a function of constrained photosynthesis under heat or water. Thus, it seems unlikely that current models can predict responses of vegetation to climate variability and change. We propose a dynamic model of damage to Rubisco and RuBP-regeneration that accounts, mechanistically, for the interactions between high temperature, light, and constrained photosynthesis under drought. Further, these predictions are illustrated by key experiments allowing model validation. We also integrated this new framework within the Advanced Canopy-Atmosphere-Soil Algorithm (ACASA). Preliminary results show that our approach can be used to predict reasonable photosynthetic dynamics. For instances, a leaf undergoing one day of drought stress will quickly decrease its maximum quantum yield of PSII (Fv/Fm), but it won't recover to unstressed levels for several days. Consequently, cumulative effect of photoinhibition on photosynthesis can cause

  3. Short communication: Characteristics of student success in an undergraduate physiology and anatomy course.

    PubMed

    Gwazdauskas, F C; McGilliard, M L; Corl, B A

    2014-10-01

    Several factors affect the success of students in college classes. The objective of this research was to determine what factors affect success of undergraduate students in an anatomy and physiology class. Data were collected from 602 students enrolled in the Agriculture and Life Sciences (ALS) 2304 Animal Physiology and Anatomy course from 2005 through 2012. The data set included 476 females (79.1%) and 126 males (20.9%). Time to complete exams was recorded for each student. For statistical analyses, students' majors were animal and poultry sciences (APSC), agricultural sciences, biochemistry, biological sciences, dairy science, and "other," which combined all other majors. All analyses were completed using the GLIMMIX procedure of SAS (SAS Institute Inc., Cary, NC). Gender, major, matriculation year, major by year interaction, gender by year interaction, and time to complete the exam affected final course grade. The significant gender effect was manifested in the final grade percentage of 75.9 ± 0.4 for female students compared with 72.3 ± 0.6 for male students. Junior males had final course grades comparable with those of females, but sophomore and senior males had lower final course grades than other combinations. Biology majors had a final grade of 82.4 ± 0.6 and this grade was greater than all other majors. Students classified as "other" had a final score of 74.4 ± 0.8, which was greater than agricultural science majors (69.5 ± 0.9). The APSC grade (72.6 ± 0.5) was higher than the agricultural science majors. Junior students had significantly greater final grades (76.1 ± 0.5) than sophomores (73.3 ± 0.6) and seniors (72.9 ± 0.9). All biology students had greater final grades than all other majors, but biochemistry juniors had greater final course grades than APSC, agricultural science, and dairy science juniors. "Other" seniors had greater final course grades than agricultural science seniors. The regression for time to complete the exam was

  4. Physiological mechanisms contributing to the increased water-use efficiency in winter wheat under deficit irrigation.

    PubMed

    Xue, Qingwu; Zhu, Zixi; Musick, Jack T; Stewart, B A; Dusek, Donald A

    2006-02-01

    Deficit irrigation in winter wheat has been practiced in the areas with limited irrigation water resources. The objectives of this study were to (i) understand the physiological basis for determinations of grain yield and water-use efficiency in grain yield (WUE) under deficit irrigation; and (ii) investigate the effect of deficit irrigation on dry matter accumulation and remobilization of pre-anthesis carbon reserves during grain filling. A field experiment was conducted in the Southern High Plains of the USA and winter wheat (cv. TAM 202) was grown on Pullman clay loam soil (fine mixed thermic Torretic Paleustoll). Treatments consisted of rain-fed, deficit irrigation from jointing to the middle of grain filling, and full irrigation. The physiological measurements included leaf water potential, net photosynthetic rate (Pn), stomatal conductance (Gs), and leaf area index. The rain-fed treatment had the lowest seasonal evapotranspiration (ET), biomass, grain yield, harvest index (HI) and WUE as a result of moderate to severe water stress from jointing to grain filling. Irrigation application increased seasonal ET, and ET increased as irrigation frequency increased. The seasonal ET increased 20% in one-irrigation treatments between jointing and anthesis, 32-46% in two-irrigation treatments, and 67% in three- and full irrigation treatments. Plant biomass, grain yield, HI and WUE increased as the result of increased ET. The increased yield under irrigation was mainly contributed by the increased number of spikes, and seeds per square meter and per spike. Among the irrigation treatments, grain yield increased significantly but the WUE increased slightly as irrigation frequency increased. The increased WUE under deficit irrigation was contributed by increased HI. Water stress during grain filling reduced Pn and Gs, and accelerated leaf senescence. However, the water stress during grain filling induced remobilization of pre-anthesis carbon reserves to grains, and the

  5. The effect of lichen-dominated biological soil crusts on growth and physiological characteristics of three plant species in a temperate desert of northwest China.

    PubMed

    Zhuang, W W; Serpe, M; Zhang, Y M

    2015-11-01

    Biocrusts (biological soil crusts) cover open spaces between vascular plants in most arid and semi-arid areas. Information on effects of biocrusts on seedling growth is controversial, and there is little information on their effects on plant growth and physiology. We examined impacts of biocrusts on growth and physiological characteristics of three habitat-typical plants, Erodium oxyrhynchum, Alyssum linifolium and Hyalea pulchella, growing in the Gurbantunggut Desert, northwest China. The influence of biocrusts on plant biomass, leaf area, leaf relative water content, photosynthesis, maximum quantum efficiency of PSII (F(v)/F(m)), chlorophyll, osmotic solutes (soluble sugars, protein, proline) and antioxidant enzymes (superoxide dismutase, catalase, peroxidase) was investigated on sites with or without biocrust cover. Biomass, leaf area, leaf water content, photosynthesis, F(v)/F(m) and chlorophyll content in crusted soils were higher than in uncrusted soils during early growth and lower later in the growth period. Soluble sugars, proline and antioxidant enzyme activity were always higher in crusted than in uncrusted soils, while soluble protein content was always lower. These findings indicate that biocrusts have different effects on these three ephemeral species during growth in this desert, primarily via effects on soil moisture, and possibly on soil nutrients. The influence of biocrusts changes during plant development: in early plant growth, biocrusts had either positive or no effect on growth and physiological parameters. However, biocrusts tended to negatively influence plants during later growth. Our results provide insights to explain why previous studies have found different effects of biocrusts on vascular plant growth. PMID:26084731

  6. The effect of lichen-dominated biological soil crusts on growth and physiological characteristics of three plant species in a temperate desert of northwest China.

    PubMed

    Zhuang, W W; Serpe, M; Zhang, Y M

    2015-11-01

    Biocrusts (biological soil crusts) cover open spaces between vascular plants in most arid and semi-arid areas. Information on effects of biocrusts on seedling growth is controversial, and there is little information on their effects on plant growth and physiology. We examined impacts of biocrusts on growth and physiological characteristics of three habitat-typical plants, Erodium oxyrhynchum, Alyssum linifolium and Hyalea pulchella, growing in the Gurbantunggut Desert, northwest China. The influence of biocrusts on plant biomass, leaf area, leaf relative water content, photosynthesis, maximum quantum efficiency of PSII (F(v)/F(m)), chlorophyll, osmotic solutes (soluble sugars, protein, proline) and antioxidant enzymes (superoxide dismutase, catalase, peroxidase) was investigated on sites with or without biocrust cover. Biomass, leaf area, leaf water content, photosynthesis, F(v)/F(m) and chlorophyll content in crusted soils were higher than in uncrusted soils during early growth and lower later in the growth period. Soluble sugars, proline and antioxidant enzyme activity were always higher in crusted than in uncrusted soils, while soluble protein content was always lower. These findings indicate that biocrusts have different effects on these three ephemeral species during growth in this desert, primarily via effects on soil moisture, and possibly on soil nutrients. The influence of biocrusts changes during plant development: in early plant growth, biocrusts had either positive or no effect on growth and physiological parameters. However, biocrusts tended to negatively influence plants during later growth. Our results provide insights to explain why previous studies have found different effects of biocrusts on vascular plant growth.

  7. Anatomy & Physiology

    MedlinePlus

    ... Central Nervous System Peripheral Nervous System Review Quiz Endocrine System Characteristics of Hormones Endocrine Glands & Their Hormones Pituitary & ... Thyroid & Parathyroid Glands Adrenal Gland Pancreas Gonads Other Endocrine Glands ... Cardiovascular System Heart Structure of the Heart Physiology of the ...

  8. Controlled alternate partial root-zone irrigation: its physiological consequences and impact on water use efficiency.

    PubMed

    Kang, Shaozhong; Zhang, Jianhua

    2004-11-01

    Controlled alternate partial root-zone irrigation (CAPRI), also called partial root-zone drying (PRD) in other literature, is a new irrigation technique and may improve the water use efficiency of crop production without significant yield reduction. It involves part of the root system being exposed to drying soil while the remaining part is irrigated normally. The wetted and dried sides of the root system are alternated with a frequency according to soil drying rate and crop water requirement. The irrigation system is developed on the basis of two theoretical backgrounds. (i) Fully irrigated plants usually have widely opened stomata. A small narrowing of the stomatal opening may reduce water loss substantially with little effect on photosynthesis. (ii) Part of the root system in drying soil can respond to the drying by sending a root-sourced signal to the shoots where stomata may be inhibited so that water loss is reduced. In the field, however, the prediction that reduced stomatal opening may reduce water consumption may not materialize because stomatal control only constitutes part of the total transpirational resistance. The boundary resistance from the leaf surface to the outside of the canopy may be so substantial that reduction in stomatal conductance is small and may be partially compensated by the increase in leaf temperature. It is likely that densely populated field crops, such as wheat and maize, may have a different stomatal control over transpiration from that of fruit trees which are more sparsely separated. It was discussed how long the stomata can keep 'partially' closed when a prolonged and repeated 'partial' soil drying is applied and what role the rewatering-stimulated new root growth may play in sensing the repeated soil drying. The physiological and morphological alternation of plants under partial root-zone irrigation may bring more benefits to crops than improved water use efficiency where carbon redistribution among organs is crucial to the

  9. Physiological response of wild dugongs (Dugong dugon) to out-of-water sampling for health assessment

    USGS Publications Warehouse

    Lanyon, Janet M.; Sneath, Helen L.; Long, Trevor; Bonde, Robert K.

    2010-01-01

    The dugong (Dugong dugon) is a vulnerable marine mammal with large populations living in urban Queensland waters. A mark-recapture program for wild dugongs has been ongoing in southern Queensland since 2001. This program has involved capture and in-water sampling of more than 700 dugongs where animals have been held at the water surface for 5 min to be gene-tagged, measured, and biopsied. In 2008, this program expanded to examine more comprehensively body condition, reproductive status, and the health of wild dugongs in Moreton Bay. Using Sea World's research vessel, captured dugongs were lifted onto a boat and sampled out-of-water to obtain accurate body weights and morphometrics, collect blood and urine samples for baseline health parameters and hormone profiles, and ultrasound females for pregnancy status. In all, 30 dugongs, including two pregnant females, were sampled over 10 d and restrained on deck for up to 55 min each while biological data were collected. Each of the dugongs had their basic temperature-heart rate-respiration (THR) monitored throughout their period of handling, following protocols developed for the West Indian manatee (Trichechus manatus). This paper reports on the physiological response of captured dugongs during this out-of-water operation as indicated by their vital signs and the suitability of the manatee monitoring protocols to this related sirenian species. A recommendation is made that the range of vital signs of these wild dugongs be used as benchmark criteria of normal parameters for other studies that intend to sample dugongs out-of-water.

  10. Background adaptation and water acidification affect pigmentation and stress physiology of tilapia, Oreochromis mossambicus.

    PubMed

    van der Salm, A L; Spanings, F A T; Gresnigt, R; Bonga, S E Wendelaar; Flik, G

    2005-10-01

    The ability to adjust skin darkness to the background is a common phenomenon in fish. The hormone alpha-melanophore-stimulating hormone (alphaMSH) enhances skin darkening. In Mozambique tilapia, Oreochromis mossambicus L., alphaMSH acts as a corticotropic hormone during adaptation to water with a low pH, in addition to its role in skin colouration. In the current study, we investigated the responses of this fish to these two environmental challenges when it is exposed to both simultaneously. The skin darkening of tilapia on a black background and the lightening on grey and white backgrounds are compromised in water with a low pH, indicating that the two vastly different processes both rely on alphaMSH-regulatory mechanisms. If the water is acidified after 25 days of undisturbed background adaptation, fish showed a transient pigmentation change but recovered after two days and continued the adaptation of their skin darkness to match the background. Black backgrounds are experienced by tilapia as more stressful than grey or white backgrounds both in neutral and in low pH water. A decrease of water pH from 7.8 to 4.5 applied over a two-day period was not experienced as stressful when combined with background adaptation, based on unchanged plasma pH and plasma alphaMSH, and Na levels. However, when water pH was lowered after 25 days of undisturbed background adaptation, particularly alphaMSH levels increased chronically. In these fish, plasma pH and Na levels had decreased, indicating a reduced capacity to maintain ion-homeostasis, implicating that the fish indeed experience stress. We conclude that simultaneous exposure to these two types of stressor has a lower impact on the physiology of tilapia than subsequent exposure to the stressors.

  11. Differential responses of grapevine rootstocks to water stress are associated with adjustments in fine root hydraulic physiology and suberization.

    PubMed

    Barrios-Masias, F H; Knipfer, T; McElrone, A J

    2015-09-01

    Water deficits are known to alter fine root structure and function, but little is known about how these responses contribute to differences in drought resistance across grapevine rootstocks. The ways in which water deficit affects root anatomical and physiological characteristics were studied in two grapevine rootstocks considered as low-medium (101-14Mgt) and highly (110R) drought resistant. Rootstocks were grown under prolonged and repeated drying cycles or frequent watering ('dry' and 'wet' treatments, respectively), and the following parameters were evaluated: root osmotic and hydrostatic hydraulic conductivity (Lp os and Lp hyd, respectively), suberization, steady-state root pressure (P rs), sap exudation rates, sap osmotic potential, and exosmotic relaxation curves. For both rootstocks, the 'dry' treatment reduced fine root Lp, elicited earlier root suberization and higher sap osmotic potential, and generated greater P rs after rewatering, but the rootstocks responded differently under these conditions. Lp os, Lp hyd, and sap exudation rates were significantly higher in 110R than in 101-14Mgt, regardless of moisture treatment. Under 'dry' conditions, 110R maintained a similar Lp os and decreased the Lp hyd by 36% compared with 'wet' conditions, while both parameters were decreased by at least 50% for 101-14Mgt under 'dry' conditions. Interestingly, build-up of P rs in 110R was 34% lower on average than in 101-14Mgt, suggesting differences in the development of suberized apoplastic barriers between the rootstocks as visualized by analysis of suberization from fluorescence microscopy. Consistent with this pattern, 110R exhibited the greatest exosmotic Lp os (i.e. Lp os of water flowing from roots to the soil) as determined from relaxation curves under wet conditions, where backflow may have limited its capacity to generate positive xylem pressure. The traits studied here can be used in combination to provide new insights needed for screening drought resistance

  12. Differential responses of grapevine rootstocks to water stress are associated with adjustments in fine root hydraulic physiology and suberization

    PubMed Central

    Barrios-Masias, F.H.; Knipfer, T.; McElrone, A.J.

    2015-01-01

    Water deficits are known to alter fine root structure and function, but little is known about how these responses contribute to differences in drought resistance across grapevine rootstocks. The ways in which water deficit affects root anatomical and physiological characteristics were studied in two grapevine rootstocks considered as low–medium (101-14Mgt) and highly (110R) drought resistant. Rootstocks were grown under prolonged and repeated drying cycles or frequent watering (‘dry’ and ‘wet’ treatments, respectively), and the following parameters were evaluated: root osmotic and hydrostatic hydraulic conductivity (Lp os and Lp hyd, respectively), suberization, steady-state root pressure (P rs), sap exudation rates, sap osmotic potential, and exosmotic relaxation curves. For both rootstocks, the ‘dry’ treatment reduced fine root Lp, elicited earlier root suberization and higher sap osmotic potential, and generated greater P rs after rewatering, but the rootstocks responded differently under these conditions. Lp os, Lp hyd, and sap exudation rates were significantly higher in 110R than in 101-14Mgt, regardless of moisture treatment. Under ‘dry’ conditions, 110R maintained a similar Lp os and decreased the Lp hyd by 36% compared with ‘wet’ conditions, while both parameters were decreased by at least 50% for 101-14Mgt under ‘dry’ conditions. Interestingly, build-up of P rs in 110R was 34% lower on average than in 101-14Mgt, suggesting differences in the development of suberized apoplastic barriers between the rootstocks as visualized by analysis of suberization from fluorescence microscopy. Consistent with this pattern, 110R exhibited the greatest exosmotic Lp os (i.e. Lp os of water flowing from roots to the soil) as determined from relaxation curves under wet conditions, where backflow may have limited its capacity to generate positive xylem pressure. The traits studied here can be used in combination to provide new insights needed for

  13. Differential responses of grapevine rootstocks to water stress are associated with adjustments in fine root hydraulic physiology and suberization.

    PubMed

    Barrios-Masias, F H; Knipfer, T; McElrone, A J

    2015-09-01

    Water deficits are known to alter fine root structure and function, but little is known about how these responses contribute to differences in drought resistance across grapevine rootstocks. The ways in which water deficit affects root anatomical and physiological characteristics were studied in two grapevine rootstocks considered as low-medium (101-14Mgt) and highly (110R) drought resistant. Rootstocks were grown under prolonged and repeated drying cycles or frequent watering ('dry' and 'wet' treatments, respectively), and the following parameters were evaluated: root osmotic and hydrostatic hydraulic conductivity (Lp os and Lp hyd, respectively), suberization, steady-state root pressure (P rs), sap exudation rates, sap osmotic potential, and exosmotic relaxation curves. For both rootstocks, the 'dry' treatment reduced fine root Lp, elicited earlier root suberization and higher sap osmotic potential, and generated greater P rs after rewatering, but the rootstocks responded differently under these conditions. Lp os, Lp hyd, and sap exudation rates were significantly higher in 110R than in 101-14Mgt, regardless of moisture treatment. Under 'dry' conditions, 110R maintained a similar Lp os and decreased the Lp hyd by 36% compared with 'wet' conditions, while both parameters were decreased by at least 50% for 101-14Mgt under 'dry' conditions. Interestingly, build-up of P rs in 110R was 34% lower on average than in 101-14Mgt, suggesting differences in the development of suberized apoplastic barriers between the rootstocks as visualized by analysis of suberization from fluorescence microscopy. Consistent with this pattern, 110R exhibited the greatest exosmotic Lp os (i.e. Lp os of water flowing from roots to the soil) as determined from relaxation curves under wet conditions, where backflow may have limited its capacity to generate positive xylem pressure. The traits studied here can be used in combination to provide new insights needed for screening drought resistance

  14. Physiology of Fluid and Electrolyte Responses During Inactivity: Water Immersion and Bed Rest

    NASA Technical Reports Server (NTRS)

    Greenleaf, John E.

    1984-01-01

    This manuscript emphasizes the physiology of fluid-electrolyte-hormonal responses during the prolonged inactivity of bed rest and water immersion. An understanding of the total mechanism of adaptation (deconditioning) should provide more insight into the conditioning process. Findings that need to be confirmed during bed rest and immersion are: (1) the volume and tissues of origin of fluid shifted to the thorax and head; (2) interstitial fluid pressure changes in muscle and subcutaneous tissue, particularly during immersion; and (3) the composition of the incoming presumably interstitial fluid that contributes to the early hypervolemia. Better resolution of the time course and source of the diuretic fluid is needed. Important data will be forthcoming when hypotheses are tested involving the probable action of the emerging diuretic and natriuretic hormones, between themselves and among vasopressin and aldosterone, on diuresis and blood pressure control.

  15. Novel mineral-oxidizing bacteria from Montserrat (W.I.): physiological and phylogenetic characteristics

    SciTech Connect

    A. Yahya; F. F. Roberto; D. B. Johnson

    1999-06-01

    Four mesophilic acidophilic bacteria isolated from the Caribbean island of Montserrat have been studied to establish their taxonomic relationship to other metal-metabolizing bacteria and to analyze their potential role in mineral processing. Two of the isolates have some physiological and morphological traits in common with Thiobacillus ferrooxidans (Gram negative, iron-oxidizing mesophilic rods) but differed from T. ferrooxidans in displaying chemolitho-heterotrophic growth in ferrous iron/yeast extract medium and greater sensitivity to some metals. Isolates RIV-14 and L-15 were, in contrast, Gram positive, spore-forming rods that displayed considerable metabolic flexibility, and resembled moderately thermophilic Sulfobacillus spp. All the Montserrat isolates were able to oxidize pyrite in pure culture.

  16. Morphological, physiological and enzymatic characteristics of cephalosporin acylase-producing Arthrobacter strain 45-8A.

    PubMed

    Zhang, Q J; Xu, W X

    1993-01-01

    A bacterial strain producing cephalosporin acylases was isolated from soil. The morphological and physiological properties of this strain suggest that it belongs to the genus Arthrobacter, and the isolate was therefore designated Arthrobacter strain 45-8A. Substrate specificity of the enzyme was examined. The enzyme can convert both cephalosporin acid to 7-aminocephalosporanic acid. An interesting feature of the acylases is their temperature-dependent regulation. Activity of acylases was detected in strain 45-8A grown at temperature below 30 degrees C, but was not observed at higher temperature. Arthrobacter strain 45-8A did not exhibit beta-lactamase activity, even though its resistance to cephalosporin C was very strong (> 2000 micrograms/ml). This is quite beneficial for its application in the manufacture of 7-aminocephalosporanic acid. PMID:8484708

  17. Physiological characteristics of Thiomicrospira sp. strain L-12 isolated from deep-sea hydrothermal vents

    SciTech Connect

    Ruby, E.G.; Jannasch, H.W.

    1982-01-01

    Growth of the obligately chemolithotrophic Thiomicrospira sp. strain L-12, isolated from a hydrothermal vent at a depth of 2,550 m in the Galapagos Rift region, was optimal at pH 8 and required 200 mM Na/sup +/ and divalent ions (Ca/sup 2 +/ and Mg/sup 2 +/). The organism was microaerophilic and tolerated 300 ..mu..M sulfide without a decrease in the rate of CO/sub 2/ incorporation. Growth and CO/sub 2/ incorporation occurred within the temperature range of 10 to 35/sup 0/C, with both optimal at 25/sup 0/C. At the in situ pressure of 250 atm, the rate of CO/sub 2/ incorporation was reduced by 25% relative to that measured at 1 atm; it was entirely suppressed at 500 atm. The results of this physiological characterization suggest that Thiomicrospira sp. strain L-12 can be an active autotroph in the hydrothermal environment.

  18. Characteristics of phytoplankton physiology inferred from chlorophyll fluorescence in the western Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Park, Jisoo; Gorbunov, Maxim Y.; Ko, Eunho; Cho, Kyoung-Ho; Yang, Eun Jin; Jung, Jinyoung; Kang, Sung Ho

    2016-04-01

    A recent Arctic survey in the Chukchi and East Siberian Sea using icebreaker R/V Araon revealed some interesting feature of vertical distribution of phytoplankton physiology in 2015 summer. A custom-built Fluorescence Induction and Relaxation (FIRe) system was used for measuring photochemical parameters such as maximum photochemical efficiency of photosystem II (Fv/Fm) and functional absorption cross section in near-surface ocean. These parameters provide an express diagnostic of the effects of environmental factors, including nutrient limitation and light acclimation on phytoplankton assemblages. Time-series of satellite ocean colour data were also used for observing large scaled spatial distribution of phytoplankton and its seasonality related with sea ice distributions. Possible implications of these results will be discussed.

  19. Physiological performance of the cold-water coral Dendrophyllia cornigera reveals its preference for temperate environments

    NASA Astrophysics Data System (ADS)

    Gori, Andrea; Reynaud, Stephanie; Orejas, Covadonga; Gili, Josep-Maria; Ferrier-Pagès, Christine

    2014-09-01

    Cold-water corals (CWCs) are key ecosystem engineers in deep-sea benthic communities around the world. Their distribution patterns are related to several abiotic and biotic factors, of which seawater temperature is arguably one of the most important due to its role in coral physiological processes. The CWC Dendrophyllia cornigera has the particular ability to thrive in several locations in which temperatures range from 11 to 17 °C, but to be apparently absent from most CWC reefs at temperatures constantly below 11 °C. This study thus aimed to assess the thermal tolerance of this CWC species, collected in the Mediterranean Sea at 12 °C, and grown at the three relevant temperatures of 8, 12, and 16 °C. This species displayed thermal tolerance to the large range of seawater temperatures investigated, but growth, calcification, respiration, and total organic carbon (TOC) fluxes severely decreased at 8 °C compared to the in situ temperature of 12 °C. Conversely, no significant differences in calcification, respiration, and TOC fluxes were observed between corals maintained at 12 and 16 °C, suggesting that the fitness of this CWC is higher in temperate rather than cold environments. The capacity to maintain physiological functions between 12 and 16 °C allows D. cornigera to be the most abundant CWC species in deep-sea ecosystems where temperatures are too warm for other CWC species (e.g., Canary Islands). This study also shows that not all CWC species occurring in the Mediterranean Sea (at deep-water temperatures of 12-14 °C) are currently living at their upper thermal tolerance limit.

  20. Associations of miRNA polymorphisms and female physiological characteristics with breast cancer risk in Chinese population.

    PubMed

    Zhang, M; Jin, M; Yu, Y; Zhang, S; Wu, Y; Liu, H; Liu, H; Chen, B; Li, Q; Ma, X; Chen, K

    2012-03-01

    mircoRNAs (miRNAs) play important roles on regulation of gene expressions. Aberrant expression of miRNAs was involved in various biological and pathological processes, including tumorigenesis of breast cancer. Single-nucleotide polymorphisms (SNPs) were implicated in altered expression or biological functions of mature miRNAs. To explore the relevance of miRNA polymorphisms and female physiological characteristics to breast cancer risk, SNPs located within hsa-miR-605 (rs2043556), hsa-miR-149 (rs2292832), hsa-miR-27a (rs895819), hsa-miR-196a-2 (rs11614913) and hsa-miR-618 (rs2682818) were selected, and their associations with breast cancer risk were analysed. In addition, associations between physiological characteristics-related factors and breast cancer risk were estimated too. We found that the ones with menarche age less than 16 years had increased breast cancer risk (OR = 2.10, 95% CI: 1.23-3.60). Marginally significant association between rs11614913 CT/CC genotypes and reduced breast cancer risk was observed (OR = 0.65, 95% CI: 0.40-1.06), while no significance was detected about the other miRNA polymorphisms. We concluded that menarche at less than 16 years old increased breast cancer risk, while the genetic variants in miR-196-a-2 might decrease the risk.

  1. Ammonia pollution characteristics of centralized drinking water sources in China.

    PubMed

    Fu, Qing; Zheng, Binghui; Zhao, Xingru; Wang, Lijing; Liu, Changming

    2012-01-01

    The characteristics of ammonia in drinking water sources in China were evaluated during 2005-2009. The spatial distribution and seasonal changes of ammonia in different types of drinking water sources of 22 provinces, 5 autonomous regions and 4 municipalities were investigated. The levels of ammonia in drinking water sources follow the order of river > lake/reservoir > groundwater. The levels of ammonia concentration in river sources gradually decreased from 2005 to 2008, while no obvious change was observed in the lakes/reservoirs and groundwater drinking water sources. The proportion of the type of drinking water sources is different in different regions. In river drinking water sources, the ammonia level was varied in different regions and changed seasonally. The highest value and wide range of annual ammonia was found in South East region, while the lowest value was found in Southwest region. In lake/reservoir drinking water sources, the ammonia levels were not varied obviously in different regions. In underground drinking water sources, the ammonia levels were varied obviously in different regions due to the geological permeability and the natural features of regions. In the drinking water sources with higher ammonia levels, there are enterprises and wastewater drainages in the protected areas of the drinking water sources.

  2. [Stable Isotope Characteristics in Different Water Bodies in Changsha and Implications for the Water Cycle].

    PubMed

    Li, Guang; Zhang, Xin-ping; Zhang, Li-feng; Wang, Yue-feng; Deng, Xiao-jun; Yang, Liu; Lei, Chao-gui

    2015-06-01

    Analysis of the variation characteristics of different water bodies is the basis of applying isotopic tracer technique in regional water cycle research. Based on the samples of atmospheric precipitation, surface water (river water) and groundwater (spring water and well water) in Changsha from January 2012 to December 2013, the study analyzed the variation characteristics of δD and δ(18)O in different water bodies. The results showed that the values of D and 18O in precipitation of Changsha showed obvious seasonal variation because of the seasonal difference of the water vapor source, and it showed significant negative correlation between δ(18)O in precipitation and some meteorological factors such as the temperature and the amount, the local meteoric water line revealed the climatic characteristic of humid and rainy in Changsha; the fluctuation of 8D and 80 in surface water was more moderate than those in precipitation, and the seasonal variation of stable isotope value showed lagging characteristic compared with that in precipitation, the difference of river water line (RWL) indicated that the main supply sources of surface water were changing in different seasons; the fluctuation of δD and δ(18)O in groundwater was the least, the variation ranges and mean values of δD and δ(18)O in spring water and well water were very close, it showed that there were some hydraulic connections in the two water bodies, the values of δD and δ(18)O in groundwater were constantly lower during drought months, this phenomenon might have a certain relationship with the increasing absorbency of tree roots from groundwater. The results of the study have certain guiding significance for rational utilization of water resources in the region. PMID:26387312

  3. Structural characteristics of thermosensitive chitosan glutamate hydrogels in variety of physiological environments

    NASA Astrophysics Data System (ADS)

    Modrzejewska, Z.; Nawrotek, K.; Maniukiewicz, W.; Douglas, T.

    2014-09-01

    In this paper the properties of thermosensitive chitosan hydrogels prepared with the use of chitosan glutamate and β-glycerophosphate are presented. The study is focused on the determination of changes in the hydrogel structure in different environments: during conditioning in water and buffer at pH 7 and pH 2 respectively. The structure of gels was observed under the Scanning Electron Microscopy (SEM) and was investigated by infrared (IR) spectroscopy. The crystallinity of gel structure was determined by X-ray diffraction analysis (XRD). On the basis of structural changes during the conditioning in water a mechanism of their formation was proposed.

  4. Liquid state DNP for water accessibility measurements on spin-labeled membrane proteins at physiological temperatures.

    PubMed

    Doll, Andrin; Bordignon, Enrica; Joseph, Benesh; Tschaggelar, René; Jeschke, Gunnar

    2012-09-01

    We demonstrate the application of continuous wave dynamic nuclear polarization (DNP) at 0.35 T for site-specific water accessibility studies on spin-labeled membrane proteins at concentrations in the 10-100 μM range. The DNP effects at such low concentrations are weak and the experimentally achievable dynamic nuclear polarizations can be below the equilibrium polarization. This sensitivity problem is solved with an optimized home-built DNP probe head consisting of a dielectric microwave resonator and a saddle coil as close as possible to the sample. The performance of the probe head is demonstrated with both a modified pulsed EPR spectrometer and a dedicated CW EPR spectrometer equipped with a commercial NMR console. In comparison to a commercial pulsed ENDOR resonator, the home-built resonator has an FID detection sensitivity improvement of 2.15 and an electron spin excitation field improvement of 1.2. The reproducibility of the DNP results is tested on the water soluble maltose binding protein MalE of the ABC maltose importer, where we determine a net standard deviation of 9% in the primary DNP data in the concentration range between 10 and 100 μM. DNP parameters are measured in a spin-labeled membrane protein, namely the vitamin B(12) importer BtuCD in both detergent-solubilized and reconstituted states. The data obtained in different nucleotide states in the presence and absence of binding protein BtuF reveal the applicability of this technique to qualitatively extract water accessibility changes between different conformations by the ratio of primary DNP parameters ϵ. The ϵ-ratio unveils the physiologically relevant transmembrane communication in the transporter in terms of changes in water accessibility at the cytoplasmic gate of the protein induced by both BtuF binding at the periplasmic region of the transporter and ATP binding at the cytoplasmic nucleotide binding domains.

  5. Liquid state DNP for water accessibility measurements on spin-labeled membrane proteins at physiological temperatures

    NASA Astrophysics Data System (ADS)

    Doll, Andrin; Bordignon, Enrica; Joseph, Benesh; Tschaggelar, René; Jeschke, Gunnar

    2012-09-01

    We demonstrate the application of continuous wave dynamic nuclear polarization (DNP) at 0.35 T for site-specific water accessibility studies on spin-labeled membrane proteins at concentrations in the 10-100 μM range. The DNP effects at such low concentrations are weak and the experimentally achievable dynamic nuclear polarizations can be below the equilibrium polarization. This sensitivity problem is solved with an optimized home-built DNP probe head consisting of a dielectric microwave resonator and a saddle coil as close as possible to the sample. The performance of the probe head is demonstrated with both a modified pulsed EPR spectrometer and a dedicated CW EPR spectrometer equipped with a commercial NMR console. In comparison to a commercial pulsed ENDOR resonator, the home-built resonator has an FID detection sensitivity improvement of 2.15 and an electron spin excitation field improvement of 1.2. The reproducibility of the DNP results is tested on the water soluble maltose binding protein MalE of the ABC maltose importer, where we determine a net standard deviation of 9% in the primary DNP data in the concentration range between 10 and 100 μM. DNP parameters are measured in a spin-labeled membrane protein, namely the vitamin B12 importer BtuCD in both detergent-solubilized and reconstituted states. The data obtained in different nucleotide states in the presence and absence of binding protein BtuF reveal the applicability of this technique to qualitatively extract water accessibility changes between different conformations by the ratio of primary DNP parameters ɛ. The ɛ-ratio unveils the physiologically relevant transmembrane communication in the transporter in terms of changes in water accessibility at the cytoplasmic gate of the protein induced by both BtuF binding at the periplasmic region of the transporter and ATP binding at the cytoplasmic nucleotide binding domains.

  6. Physiological Responses of a Model Marine Diatom to Fast pH Changes: Special Implications of Coastal Water Acidification

    PubMed Central

    Wu, Yaping; Beardall, John; Gao, Kunshan

    2015-01-01

    Diatoms and other phytoplankton in coastal waters experience rapid pH changes in milieu due to high biological activities and/or upwelled CO2-rich waters. While CO2 concentrating mechanisms (CCMs) are employed by all diatoms tested to counter low CO2 availability in seawater, little is known how this mechanism responds to fast pH changes. In the present study, the model diatom Thalassiosira pseudonana was acclimated for 20 generations to low pH (7.81) at an elevated CO2 of 1000 μatm (HC) or to high pH (8.18) at ambient CO2 levels of 390 μatm (LC), then its physiological characteristics were investigated as cells were shifted from HC to LC or vice versa. The maximal electron transport rate (ETRmax) in the HC-acclimated cells was immediately reduced by decreased CO2 availability, showing much lower values compared to that of the LC-acclimated cells. However, the cells showed a high capacity to regain their photochemical performance regardless of the growth CO2 levels, with their ETRmax values recovering to initial levels in about 100 min. This result indicates that this diatom might modulate its CCMs quickly to maintain a steady state supply of CO2, which is required for sustaining photosynthesis. In addition, active uptake of CO2 could play a fundamental role during the induction of CCMs under CO2 limitation, since the cells maintained high ETR even when both intracellular and periplasmic carbonic anhydrases were inhibited. It is concluded that efficient regulation of the CCM is one of the key strategies for diatoms to survive in fast changing pH environment, e.g. for the tested species, which is a dominant species in coastal waters where highly fluctuating pH is observed. PMID:26496125

  7. [Effects of cinnamic acid and vanillin on grafted eggplant root growth and physiological characteristics].

    PubMed

    Chen, Shao-Li; Zhou, Bao-Li; Lin, Shan-Shan; Li, Xia; Ye, Xue-Ling

    2010-06-01

    Choosing Solanum torvum as rootstock and cultivated Xi'anlü eggplant as scion, a pot culture experiment was conducted to study the effects of autotoxic substances (cinnamic acid and vanillin) on the root growth, antioxidase activity, and osmoregulation substances content of grafted eggplant, own-rooted eggplant, and rootstock eggplant. Cinnamic acid and vanillin had allelopathic effects on the root system of test eggplants, with low concentration promoting and higher concentration inhibiting the root growth and physiological metabolism. For own-rooted eggplant, the critical concentration of cinnamic acid and vanillin for promotion or inhibition was 0.1 mmol x kg(-1) and 0.5 mmol x kg(-1), respectively; whereas for grafted and rootstock eggplants, it was 0.5 mmol x kg(-1) and 1 mmol x kg(-1), respectively. The root resistance to autotoxic substances was in the order of root-stock eggplant > grafted eggplant > own-rooted eggplant. Higher concentration cinamic acid (0.5-4 mmol x kg(-1)) and vanillin (1-4 mmol x kg(-1)) enhanced the SOD enzyme activity and the proline and soluble sugar contents of grafted eggplant root by 8.50%-24.50%; 9.39%-27.64%, and 12.77%-81.81%, respectively, compared with own-rooted eggplant. The soluble protein content, fresh mass, dry mass, and root activity of grafted eggplant roots were significantly higher than those of own-rooted eggplant, suggesting that grafted eggplant had a strong resistance of rootstocks to autotoxic substances, which alleviated the negative effect of autotoxic substances on root growth.

  8. Physiological Characteristics of Photosynthesis and Respiration in Stems of Populus tremuloides Michx. 1

    PubMed Central

    Foote, Knowlton C.; Schaedle, Michail

    1976-01-01

    The physiological responses of 6- to 8-year-old aspen (Populus tremuloides Michx.) stems to temperature, light, and CO2 concentration were investigated in the field throughout the year using infrared CO2 analysis. Light response studies showed that the rate of gross photosynthesis was linear from 0 to 400 ft-c (0 to 1.6 mw/cm2 of 400-700 nm) with light saturation being reached between 800 to 1400 ft-c (3.2 to 5.6 mw/cm2 of 400-700 nm). At this light intensity, the respiratory CO2 loss was reduced to 10 to 15% of dark rates. Net photosynthetic CO2 uptake was not observed even at intensities as high as 3400 ft-c (13.6 mw/cm2 of 400-700 nm). The light response curve was similar for both winter and summer stems. During summer months, the respiratory and photosynthetic rates of the aspen stem increased with temperature at a near constant rate between 5 and 35 C. For winter stems, the gross photosynthetic rate increased in a pattern similar to the dark respiratory rate as the temperature rose from 3 to 17 C. Below 0 C and above 17 C, however, the gross photosynthetic rate fell off in relation to the respiratory rate so that the per cent of CO2 reassimilated decreased from 75% to less than 50%. Measurable bark photosynthetic activity was not observed below —3 C. The gross photosynthetic rate of stems was not affected when the gas passing through the cuvette contained concentrations of CO2 ranging from 0 to 580 μl CO2/l air. PMID:16659628

  9. Physiological strategies of co-occurring oaks in a water- and nutrient-limited ecosystem.

    PubMed

    Renninger, Heidi J; Carlo, Nicholas; Clark, Kenneth L; Schäfer, Karina V R

    2014-02-01

    Oak species are well suited to water-limited conditions by either avoiding water stress through deep rooting or tolerating water stress through tight stomatal control. In co-occurring species where resources are limited, species may either partition resources in space and/or time or exhibit differing efficiencies in the use of limited resources. Therefore, this study seeks to determine whether two co-occurring oak species (Quercus prinus L. and Quercus velutina Lam.) differ in physiological parameters including photosynthesis, stomatal conductance, water-use (WUE) and nitrogen-use efficiency (NUE), as well as to characterize transpiration and average canopy stomatal responses to climatic variables in a sandy, well-drained and nutrient-limited ecosystem. The study was conducted in the New Jersey Pinelands and we measured sap flux over a 3-year period, as well as leaf gas exchange, leaf nitrogen and carbon isotope concentrations. Both oak species showed relatively steep increases in leaf-specific transpiration at low vapor pressure deficit (VPD) values before maximum transpiration rates were achieved, which were sustained over a broad range in VPD. This suggests tight stomatal control over transpiration in both species, although Q. velutina showed significantly higher leaf-level and canopy-level stomatal conductance than Q. prinus. Average daytime stomatal conductance was positively correlated with soil moisture and both oak species maintained at least 75% of their maximum canopy stomatal conductance at soil moistures in the upper soil layer (0-0.3 m) as low as 0.03 m(3) m(3)(-3). Quercus velutina had significantly higher photosynthetic rates, maximum Rubisco-limited and electron-transport-limited carboxylation rates, dark respiration rates and nitrogen concentration per unit leaf area than Q. prinus. However, both species exhibited similar WUEs and NUEs. Therefore, Q. prinus has a more conservative resource-use strategy, while Q. velutina may need to exploit niches

  10. Molecular, physiological and biochemical responses of Theobroma cacao L. genotypes to soil water deficit.

    PubMed

    Santos, Ivanildes C Dos; Almeida, Alex-Alan Furtado de; Anhert, Dário; Conceição, Alessandro S da; Pirovani, Carlos P; Pires, José L; Valle, Raúl René; Baligar, Virupax C

    2014-01-01

    Six months-old seminal plants of 36 cacao genotypes grown under greenhouse conditions were subjected to two soil water regimes (control and drought) to assess, the effects of water deficit on growth, chemical composition and oxidative stress. In the control, soil moisture was maintained near field capacity with leaf water potentials (ΨWL) ranging from -0.1 to -0.5 MPa. In the drought treatment, the soil moisture was reduced gradually by withholding additional water until ΨWL reached values of between -2.0 to -2.5 MPa. The tolerant genotypes PS-1319, MO-20 and MA-15 recorded significant increases in guaiacol peroxidase activity reflecting a more efficient antioxidant metabolism. In relation to drought tolerance, the most important variables in the distinguishing contrasting groups were: total leaf area per plant; leaf, stem and total dry biomass; relative growth rate; plant shoot biomass and leaf content of N, Ca, and Mg. From the results of these analyses, six genotypes were selected with contrasting characteristics for tolerance to soil water deficit [CC-40, C. SUL-4 and SIC-2 (non-tolerant) and MA-15, MO-20, and PA-13 (tolerant)] for further assessment of the expression of genes NCED5, PP2C, psbA and psbO to water deficit. Increased expression of NCED5, PP2C, psbA and psbO genes were found for non-tolerant genotypes, while in the majority of tolerant genotypes there was repression of these genes, with the exception of PA-13 that showed an increased expression of psbA. Mutivariate analysis showed that growth variables, leaf and total dry biomass, relative growth rate as well as Mg content of the leaves were the most important factor in the classification of the genotypes as tolerant, moderately tolerant and sensitive to water deficit. Therefore these variables are reliable plant traits in the selection of plants tolerant to drought.

  11. Molecular, Physiological and Biochemical Responses of Theobroma cacao L. Genotypes to Soil Water Deficit

    PubMed Central

    dos Santos, Ivanildes C.; de Almeida, Alex-Alan Furtado; Anhert, Dário; da Conceição, Alessandro S.; Pirovani, Carlos P.; Pires, José L.; Valle, Raúl René; Baligar, Virupax C.

    2014-01-01

    Six months-old seminal plants of 36 cacao genotypes grown under greenhouse conditions were subjected to two soil water regimes (control and drought) to assess, the effects of water deficit on growth, chemical composition and oxidative stress. In the control, soil moisture was maintained near field capacity with leaf water potentials (ΨWL) ranging from −0.1 to −0.5 MPa. In the drought treatment, the soil moisture was reduced gradually by withholding additional water until ΨWL reached values of between −2.0 to −2.5 MPa. The tolerant genotypes PS-1319, MO-20 and MA-15 recorded significant increases in guaiacol peroxidase activity reflecting a more efficient antioxidant metabolism. In relation to drought tolerance, the most important variables in the distinguishing contrasting groups were: total leaf area per plant; leaf, stem and total dry biomass; relative growth rate; plant shoot biomass and leaf content of N, Ca, and Mg. From the results of these analyses, six genotypes were selected with contrasting characteristics for tolerance to soil water deficit [CC-40, C. SUL-4 and SIC-2 (non-tolerant) and MA-15, MO-20, and PA-13 (tolerant)] for further assessment of the expression of genes NCED5, PP2C, psbA and psbO to water deficit. Increased expression of NCED5, PP2C, psbA and psbO genes were found for non-tolerant genotypes, while in the majority of tolerant genotypes there was repression of these genes, with the exception of PA-13 that showed an increased expression of psbA. Mutivariate analysis showed that growth variables, leaf and total dry biomass, relative growth rate as well as Mg content of the leaves were the most important factor in the classification of the genotypes as tolerant, moderately tolerant and sensitive to water deficit. Therefore these variables are reliable plant traits in the selection of plants tolerant to drought. PMID:25541723

  12. Molecular, physiological and biochemical responses of Theobroma cacao L. genotypes to soil water deficit.

    PubMed

    Santos, Ivanildes C Dos; Almeida, Alex-Alan Furtado de; Anhert, Dário; Conceição, Alessandro S da; Pirovani, Carlos P; Pires, José L; Valle, Raúl René; Baligar, Virupax C

    2014-01-01

    Six months-old seminal plants of 36 cacao genotypes grown under greenhouse conditions were subjected to two soil water regimes (control and drought) to assess, the effects of water deficit on growth, chemical composition and oxidative stress. In the control, soil moisture was maintained near field capacity with leaf water potentials (ΨWL) ranging from -0.1 to -0.5 MPa. In the drought treatment, the soil moisture was reduced gradually by withholding additional water until ΨWL reached values of between -2.0 to -2.5 MPa. The tolerant genotypes PS-1319, MO-20 and MA-15 recorded significant increases in guaiacol peroxidase activity reflecting a more efficient antioxidant metabolism. In relation to drought tolerance, the most important variables in the distinguishing contrasting groups were: total leaf area per plant; leaf, stem and total dry biomass; relative growth rate; plant shoot biomass and leaf content of N, Ca, and Mg. From the results of these analyses, six genotypes were selected with contrasting characteristics for tolerance to soil water deficit [CC-40, C. SUL-4 and SIC-2 (non-tolerant) and MA-15, MO-20, and PA-13 (tolerant)] for further assessment of the expression of genes NCED5, PP2C, psbA and psbO to water deficit. Increased expression of NCED5, PP2C, psbA and psbO genes were found for non-tolerant genotypes, while in the majority of tolerant genotypes there was repression of these genes, with the exception of PA-13 that showed an increased expression of psbA. Mutivariate analysis showed that growth variables, leaf and total dry biomass, relative growth rate as well as Mg content of the leaves were the most important factor in the classification of the genotypes as tolerant, moderately tolerant and sensitive to water deficit. Therefore these variables are reliable plant traits in the selection of plants tolerant to drought. PMID:25541723

  13. Flow characteristics past jellyfish and St. Vincent valves in the aortic position under physiological pulsatile flow conditions.

    PubMed

    Morsi, Y S; Sakhaeimanesh, A A

    2000-07-01

    Thrombus formation and hemolysis have been linked to the dynamic flow characteristics of heart valve prostheses. To enhance our understanding of the flow characteristics past the aortic position of a Jellyfish (JF) valve in the left ventricle, in vitro laser Doppler anemometry (LDA) measurements were carried out under physiological pulsatile flow conditions. The hemodynamic performance of the JF valve was then compared with that of the St. Vincent (SV) valve. The comparison was given in terms of mean systolic pressure drop, back flow energy losses, flow velocity, and shear stresses at various locations downstream of both valves and at cardiac outputs of 3.5 L/min, 4.5 L/min, and 6.5 L/min respectively. The results indicated that both valves created disturbed flow fields with elevated levels of turbulent shear stress as well as higher levels of turbulence in the immediate vicinity of the valve and up to 1 diameter of the pipe (D) downstream of the valve. At a location further downstream, the JF valve showed better flow characteristics than the SV in terms of velocity profiles and turbulent shear stresses. The closure volume of the SV valve was found to be 2.5 times higher than that of the JF valve. Moreover, the total back flow losses and mean systolic pressure drop also were found to be higher in the SV than the JF valve.

  14. Infrared thermal imaging as a physiological access pathway: a study of the baseline characteristics of facial skin temperatures.

    PubMed

    Nhan, B R; Chau, T

    2009-04-01

    In this study we examine the baseline characteristics of facial skin temperature, as measured by dynamic infrared thermal imaging, to gauge its potential as a physiological access pathway for non-verbal individuals with severe motor impairments. Frontal facial recordings were obtained from 12 asymptomatic adults in a resting state with a high-end infrared thermal imaging system. From the infrared thermal recordings, mean skin temperature time series were generated for regions of interest encompassing the nasal, periorbital and supraorbital areas. A 90% bandwidth for all regions of interest was found to be in the 1 Hz range. Over 70% of the time series were identified as nonstationary (p<0.05), with the nonstationary mean as the greatest contributing source. Correlation coefficients between regions were significant (p<0.05) and ranged from values of 0.30 (between periorbital and supraorbital regions) to 0.75 (between contralateral supraorbital regions). Using information measures, we concluded that the greatest degree of information existed in the nasal and periorbital regions. Mutual information existed across all regions but was especially prominent between the nasal and periorbital regions. Results from this study provide insight into appropriate analysis methods and potential discriminating features for the application of facial skin temperature as a physiological access pathway. PMID:19332894

  15. Behavioural and physiological reactions of cattle in a commercial abattoir: relationships with organisational aspects of the abattoir and animal characteristics.

    PubMed

    Bourguet, Cécile; Deiss, Véronique; Tannugi, Carole Cohen; Terlouw, E M Claudia

    2011-05-01

    Behavioural, physiological and metabolic reactions of cattle to handling and slaughter procedures were evaluated in a commercial abattoir, from arrival until slaughter. Different genders or breeds were not subjected to the same procedures due to abattoir equipment or organisational aspects of the abattoir. Reactions to similar slaughter procedures varied according to animal characteristics and could have consequences for subsequent handling procedures. Factors that appeared to cause handling problems and vocalisation were excessive pressure during restraint, and distractions in the corridor such as noise, darkness, seeing people and activity. Post-mortem muscle metabolism depended on slaughter procedures. Following stunning or halal slaughter, some animals showed head rising movements despite the abolition of the corneal reflex, suggesting that head rising is not always indicative of consciousness. Overall, this study presents concrete data on how different types of cattle may react to slaughter procedures with a direct interest for the abattoir itself but also for scientific purposes. PMID:21236588

  16. Fabric circuit board-based dry electrode and its characteristics for long-term physiological signal recording.

    PubMed

    Yoo, Jerald; Yoo, Hoi-Jun

    2011-01-01

    This paper presents a dry fabric electrode and its characteristics. For long-term physiological signal monitoring, conventional wet type electrode such as an Ag/AgCl electrode may not be sufficient, because captured signal strength degrades over time as its electrolyte dehydrates. Moreover, the electrolyte may cause skin irritation over a period of time. As a complement, a dry electrode can be used. In this work, fabric-based dry electrodes are introduced. Planar-Fabric Circuit Board (P-FCB) technology enables low cost and uniform productions of such electrodes; electrical properties of the electrodes with various materials, sizes, and time are shown. Both the strengths and drawbacks of the fabric-based electrodes are also discussed.

  17. Arbuscular Mycorrhizal Fungus Species Dependency Governs Better Plant Physiological Characteristics and Leaf Quality of Mulberry (Morus alba L.) Seedlings.

    PubMed

    Shi, Song-Mei; Chen, Ke; Gao, Yuan; Liu, Bei; Yang, Xiao-Hong; Huang, Xian-Zhi; Liu, Gui-Xi; Zhu, Li-Quan; He, Xin-Hua

    2016-01-01

    Understanding the synergic interactions between arbuscular mycorrhizal fungi (AMF) and its host mulberry (Morus alba L.), an important perennial multipurpose plant, has theoretical and practical significance in mulberry plantation, silkworm cultivation, and relevant textile industry. In a greenhouse study, we compared functional distinctions of three genetically different AMF species (Acaulospora scrobiculata, Funneliformis mosseae, and Rhizophagus intraradices) on physiological and growth characteristics as well as leaf quality of 6-month-old mulberry seedlings. Results showed that mulberry was AMF-species dependent, and AMF colonization significantly increased shoot height and taproot length, stem base and taproot diameter, leaf and fibrous root numbers, and shoot and root biomass production. Meanwhile, leaf chlorophyll a or b and carotenoid concentrations, net photosynthetic rate, transpiration rate and stomatal conductance were generally significantly greater, while intercellular CO2 concentration was significantly lower in AMF-inoculated seedlings than in non-AMF-inoculated counterparts. These trends were also generally true for leaf moisture, total nitrogen, all essential amino acids, histidine, proline, soluble protein, sugar, and fatty acid as they were significantly increased under mycorrhization. Among these three tested AMFs, significantly greater effects of AMF on above-mentioned mulberry physiological and growth characteristics ranked as F. mosseae > A. scrobiculata > R. intraradices, whilst on mulberry leaf quality (e.g., nutraceutical values) for better silkworm growth as F. mosseae ≈A. scrobiculata > R. intraradices. In conclusion, our results showed that greater mulberry biomass production, and nutritional quality varied with AMF species or was AMF-species dependent. Such improvements were mainly attributed to AMF-induced positive alterations of mulberry leaf photosynthetic pigments, net photosynthetic rate, transpiration rate, and N

  18. Arbuscular Mycorrhizal Fungus Species Dependency Governs Better Plant Physiological Characteristics and Leaf Quality of Mulberry (Morus alba L.) Seedlings.

    PubMed

    Shi, Song-Mei; Chen, Ke; Gao, Yuan; Liu, Bei; Yang, Xiao-Hong; Huang, Xian-Zhi; Liu, Gui-Xi; Zhu, Li-Quan; He, Xin-Hua

    2016-01-01

    Understanding the synergic interactions between arbuscular mycorrhizal fungi (AMF) and its host mulberry (Morus alba L.), an important perennial multipurpose plant, has theoretical and practical significance in mulberry plantation, silkworm cultivation, and relevant textile industry. In a greenhouse study, we compared functional distinctions of three genetically different AMF species (Acaulospora scrobiculata, Funneliformis mosseae, and Rhizophagus intraradices) on physiological and growth characteristics as well as leaf quality of 6-month-old mulberry seedlings. Results showed that mulberry was AMF-species dependent, and AMF colonization significantly increased shoot height and taproot length, stem base and taproot diameter, leaf and fibrous root numbers, and shoot and root biomass production. Meanwhile, leaf chlorophyll a or b and carotenoid concentrations, net photosynthetic rate, transpiration rate and stomatal conductance were generally significantly greater, while intercellular CO2 concentration was significantly lower in AMF-inoculated seedlings than in non-AMF-inoculated counterparts. These trends were also generally true for leaf moisture, total nitrogen, all essential amino acids, histidine, proline, soluble protein, sugar, and fatty acid as they were significantly increased under mycorrhization. Among these three tested AMFs, significantly greater effects of AMF on above-mentioned mulberry physiological and growth characteristics ranked as F. mosseae > A. scrobiculata > R. intraradices, whilst on mulberry leaf quality (e.g., nutraceutical values) for better silkworm growth as F. mosseae ≈A. scrobiculata > R. intraradices. In conclusion, our results showed that greater mulberry biomass production, and nutritional quality varied with AMF species or was AMF-species dependent. Such improvements were mainly attributed to AMF-induced positive alterations of mulberry leaf photosynthetic pigments, net photosynthetic rate, transpiration rate, and N

  19. Arbuscular Mycorrhizal Fungus Species Dependency Governs Better Plant Physiological Characteristics and Leaf Quality of Mulberry (Morus alba L.) Seedlings

    PubMed Central

    Shi, Song-Mei; Chen, Ke; Gao, Yuan; Liu, Bei; Yang, Xiao-Hong; Huang, Xian-Zhi; Liu, Gui-Xi; Zhu, Li-Quan; He, Xin-Hua

    2016-01-01

    Understanding the synergic interactions between arbuscular mycorrhizal fungi (AMF) and its host mulberry (Morus alba L.), an important perennial multipurpose plant, has theoretical and practical significance in mulberry plantation, silkworm cultivation, and relevant textile industry. In a greenhouse study, we compared functional distinctions of three genetically different AMF species (Acaulospora scrobiculata, Funneliformis mosseae, and Rhizophagus intraradices) on physiological and growth characteristics as well as leaf quality of 6-month-old mulberry seedlings. Results showed that mulberry was AMF-species dependent, and AMF colonization significantly increased shoot height and taproot length, stem base and taproot diameter, leaf and fibrous root numbers, and shoot and root biomass production. Meanwhile, leaf chlorophyll a or b and carotenoid concentrations, net photosynthetic rate, transpiration rate and stomatal conductance were generally significantly greater, while intercellular CO2 concentration was significantly lower in AMF-inoculated seedlings than in non-AMF-inoculated counterparts. These trends were also generally true for leaf moisture, total nitrogen, all essential amino acids, histidine, proline, soluble protein, sugar, and fatty acid as they were significantly increased under mycorrhization. Among these three tested AMFs, significantly greater effects of AMF on above-mentioned mulberry physiological and growth characteristics ranked as F. mosseae > A. scrobiculata > R. intraradices, whilst on mulberry leaf quality (e.g., nutraceutical values) for better silkworm growth as F. mosseae ≈A. scrobiculata > R. intraradices. In conclusion, our results showed that greater mulberry biomass production, and nutritional quality varied with AMF species or was AMF-species dependent. Such improvements were mainly attributed to AMF-induced positive alterations of mulberry leaf photosynthetic pigments, net photosynthetic rate, transpiration rate, and N

  20. Foulant characteristics comparison in recycling cooling water system makeup by municipal reclaimed water and surface water in power plant.

    PubMed

    Ping, Xu; Jing, Wang; Yajun, Zhang; Jie, Wang; Shuai, Si

    2015-01-01

    Due to water shortage, municipal reclaimed water rather than surface water was replenished into recycling cooling water system in power plants in some cities in China. In order to understand the effects of the measure on carbon steel corrosion, characteristics of two kinds of foulant produced in different systems were studied in the paper. Differences between municipal reclaimed water and surface water were analyzed firstly. Then, the weight and the morphology of two kinds of foulant were compared. Moreover, other characteristics including the total number of bacteria, sulfate reducing bacteria, iron bacteria, extracellular polymeric substance (EPS), protein (PN), and polysaccharide (PS) in foulant were analyzed. Based on results, it could be concluded that microbial and corrosive risk would be increased when the system replenished by municipal reclaimed water instead of surface water.

  1. Foulant Characteristics Comparison in Recycling Cooling Water System Makeup by Municipal Reclaimed Water and Surface Water in Power Plant

    PubMed Central

    Ping, Xu; Jing, Wang; Yajun, Zhang; Jie, Wang; Shuai, Si

    2015-01-01

    Due to water shortage, municipal reclaimed water rather than surface water was replenished into recycling cooling water system in power plants in some cities in China. In order to understand the effects of the measure on carbon steel corrosion, characteristics of two kinds of foulant produced in different systems were studied in the paper. Differences between municipal reclaimed water and surface water were analyzed firstly. Then, the weight and the morphology of two kinds of foulant were compared. Moreover, other characteristics including the total number of bacteria, sulfate reducing bacteria, iron bacteria, extracellular polymeric substance (EPS), protein (PN), and polysaccharide (PS) in foulant were analyzed. Based on results, it could be concluded that microbial and corrosive risk would be increased when the system replenished by municipal reclaimed water instead of surface water. PMID:25893132

  2. Foulant characteristics comparison in recycling cooling water system makeup by municipal reclaimed water and surface water in power plant.

    PubMed

    Ping, Xu; Jing, Wang; Yajun, Zhang; Jie, Wang; Shuai, Si

    2015-01-01

    Due to water shortage, municipal reclaimed water rather than surface water was replenished into recycling cooling water system in power plants in some cities in China. In order to understand the effects of the measure on carbon steel corrosion, characteristics of two kinds of foulant produced in different systems were studied in the paper. Differences between municipal reclaimed water and surface water were analyzed firstly. Then, the weight and the morphology of two kinds of foulant were compared. Moreover, other characteristics including the total number of bacteria, sulfate reducing bacteria, iron bacteria, extracellular polymeric substance (EPS), protein (PN), and polysaccharide (PS) in foulant were analyzed. Based on results, it could be concluded that microbial and corrosive risk would be increased when the system replenished by municipal reclaimed water instead of surface water. PMID:25893132

  3. [Impacts of salt stress on the growth and physiological characteristics of Rosa rugosa].

    PubMed

    Yang, Zhi-ying; Zhao, Lan-yong; Xu, Zong-da

    2011-08-01

    Taking 1-year-old cuttings of a wild type and three cultivars of Rosa rugosa as test materials, this paper studied their biomass, photosynthesis, osmotic adjustment substance contents, root activity, and ion contents under the stress of different concentration NaCl. Salt stress inhibited the growth of the cuttings, and root was more sensitive than shoot. Under salt stress, wild rose had significantly higher contents of free proline and soluble sugar than the cultivars, and the contents of free proline and soluble sugar in cultivar 'Ziyan' were higher than those in cultivars 'Zhongke 2' and 'Purple Branch'. Compared with rose cultivars, the wild rose under salt stress had smaller changes in its photosynthetic characteristics and root activity. It was suggested that wild rose had a higher resistance to salt stress than the cultivars, and cultivar 'Ziyan' had a higher resistance than 'Purple Branch' and 'Zhongke 2'. All the test indices could be used as the indicators of R. rugosa salt-tolerance.

  4. Behavioral, attitudinal, and physiologic characteristics of smoking and nonsmoking asbestos-exposed shipyard workers

    SciTech Connect

    Li, V.C.; Kim, Y.J.; Terry, P.B.; Cuthie, J.C.; Roter, D.; Emmett, E.A.; Harvey, A.; Permutt, S.

    1983-12-01

    The smoking characteristics of shipyard workers participating in an Asbestos Medical Surveillance Program (N=3991) were assessed. Sources of data were: 1) a self-assessment questionnaire on the smoking history and respiratory symptomatology of the 871 current smokers who participated in the smoking study, and 2) chest roentgenograms and pulmonary function test results and medical records for the entire population. The study population included 1711 current smokers, 988 former smokers and 1292 never smokers. The annual ''quit rate'' for former smokers had increased from less than 1% in 1961 to 4.2% in 1978. Of the 871 current smokers who participated in the smoking study, 19% had resumed smoking after having given up cigarettes for one year or longer. Men in the smoking study were reasonably well informed about the health consequences of smoking. While they perceived themselves to be susceptible to disease, and the disease to be serious, the benefits they saw in quitting were related more to economics and aesthetics than to health. When the results were age adjusted, no differences in rate of pulonary function abnormalities and chest film abnormalities were found betwen current smokers who voluntarily participated in the smoking study and those who did not. All pulmonary function testing abnormality and chest film abnormality rates were significantly lower for former smokers and never smokers.

  5. The effects of physiological adjustments on the perceptual and acoustical characteristics of simulated laryngeal vocal tremor.

    PubMed

    Lester, Rosemary A; Story, Brad H

    2015-08-01

    The purpose of this study was to determine if adjustments to the voice source [i.e., fundamental frequency (F0), degree of vocal fold adduction] or vocal tract filter (i.e., vocal tract shape for vowels) reduce the perception of simulated laryngeal vocal tremor and to determine if listener perception could be explained by characteristics of the acoustical modulations. This research was carried out using a computational model of speech production that allowed for precise control and manipulation of the glottal and vocal tract configurations. Forty-two healthy adults participated in a perceptual study involving pair-comparisons of the magnitude of "shakiness" with simulated samples of laryngeal vocal tremor. Results revealed that listeners perceived a higher magnitude of voice modulation when simulated samples had a higher mean F0, greater degree of vocal fold adduction, and vocal tract shape for /i/ vs /ɑ/. However, the effect of F0 was significant only when glottal noise was not present in the acoustic signal. Acoustical analyses were performed with the simulated samples to determine the features that affected listeners' judgments. Based on regression analyses, listeners' judgments were predicted to some extent by modulation information present in both low and high frequency bands. PMID:26328711

  6. The effects of physiological adjustments on the perceptual and acoustical characteristics of simulated laryngeal vocal tremor

    PubMed Central

    Lester, Rosemary A.; Story, Brad H.

    2015-01-01

    The purpose of this study was to determine if adjustments to the voice source [i.e., fundamental frequency (F0), degree of vocal fold adduction] or vocal tract filter (i.e., vocal tract shape for vowels) reduce the perception of simulated laryngeal vocal tremor and to determine if listener perception could be explained by characteristics of the acoustical modulations. This research was carried out using a computational model of speech production that allowed for precise control and manipulation of the glottal and vocal tract configurations. Forty-two healthy adults participated in a perceptual study involving pair-comparisons of the magnitude of “shakiness” with simulated samples of laryngeal vocal tremor. Results revealed that listeners perceived a higher magnitude of voice modulation when simulated samples had a higher mean F0, greater degree of vocal fold adduction, and vocal tract shape for /i/ vs /ɑ/. However, the effect of F0 was significant only when glottal noise was not present in the acoustic signal. Acoustical analyses were performed with the simulated samples to determine the features that affected listeners' judgments. Based on regression analyses, listeners' judgments were predicted to some extent by modulation information present in both low and high frequency bands. PMID:26328711

  7. Combining leaf physiology, hyperspectral imaging and partial least squares-regression (PLS-R) for grapevine water status assessment

    NASA Astrophysics Data System (ADS)

    Rapaport, Tal; Hochberg, Uri; Shoshany, Maxim; Karnieli, Arnon; Rachmilevitch, Shimon

    2015-11-01

    Physiological measurements are considered to be the most accurate way of assessing plant water status, but they might also be time-consuming, costly and intrusive. Since visible (VIS)-to-shortwave infrared (SWIR) imaging spectrometers are able to monitor various bio-chemical alterations in the leaf, such narrow-band instruments may offer a faster, less expensive and non-destructive alternative. This requires an intelligent downsizing of broad and noisy hyperspectra into the few most physiologically-sensitive wavelengths. In the current study, hyperspectral signatures of water-stressed grapevine leaves (Vitis vinifera L. cv. Cabernet Sauvignon) were correlated to values of midday leaf water potential (Ψl), stomatal conductance (gs) and non-photochemical quenching (NPQ) under controlled conditions, using the partial least squares-regression (PLS-R) technique. It was found that opposite reflectance trends at 530-550 nm and around 1500 nm - associated with independent changes in photoprotective pigment contents and water availability, respectively - were indicative of stress-induced alterations in Ψl, gs and NPQ. Furthermore, combining the spectral responses at these VIS and SWIR regions yielded three normalized water balance indices (WABIs), which were superior to various widely-used reflectance models in predicting physiological values at both the leaf and canopy levels. The potential of the novel WABI formulations also under field conditions demonstrates their applicability for water status monitoring and irrigation scheduling.

  8. [Correlations of reproductive parameters of water vole females (Arvicola amphibius) with morphometric and hormonal characteristics].

    PubMed

    Yuzhik, E I; Proskurnyak, L P; Nazarova, G G

    2015-01-01

    Fluctuations in water vole population size depend on abiotic and intra-population factors affecting the physiological condition of females. The relationship between variability in reproductive success and morpho-physiological characteristics of female during pregnancy is studied quite poorly. In standard vivarium conditions, the morphometric and hormonal characteristics of female were assessed at different stages of pregnancy (first trimester--days 4-7, second trimester--days 8-14, third semester--days 15-20), and their relationship with potential and actual fecundity and the level of embryonic lethality was elucidated. The general regression model was used in the data analysis. Positive correlations were found between potential fecundity and the female body mass at mating, body mass index and blood testosterone level. The reproductive parameters under study were independent of the blood thyroxin level. A positive correlation was established between the level of embryonic loss and the indices of liver and lung functions. Liver and spleen are essential for the maintenance of the female body mass homeostasis during the reproductive period. PMID:26027386

  9. Introduction to medical physiology: cellular membranes and transmembrane transport of solutes and water.

    PubMed

    Benos, D J

    1996-12-01

    This article summarizes the comments made in the introductory session of the Medical Physiology course taught at the University of Alabama School of Medicine. The main thesis is that learning physiology is easier when fundamental principles are first delineated. Four general principles of physiology (mass balance, force-flow, capacitance, and equilibrium) are discussed. Clinical medicine becomes more comprehensible when these basic principles are understood. Cellular Physiology is taught first because it forms the conceptual basis for what follows in the course. The idea that the root of clinical medicine lies in the basic sciences is emphasized.

  10. Metal bioaccumulation in aquatic species: quantification of uptake and elimination rate constants using physicochemical properties of metals and physiological characteristics of species.

    PubMed

    Veltman, Karin; Huijbregts, Mark A J; Van Kolck, Maurits; Wang, Wen-Xiong; Hendriks, A Jan

    2008-02-01

    Mechanistic bioaccumulation models are powerful tools in environmental risk assessment as they provide insight in varying accumulation patterns across species, contaminants, and conditions, and they are applicable beyond tested cases. In these models key parameters, as absorption and elimination rate constants, are predicted based on chemical specific properties and physiological characteristics. However, due to the complex environmental behavior of metals, the development of mechanistic bioaccumulation models has lagged behind that for organic chemicals. Absorption and elimination rate constants of organic substances have long been linked to their octanol-water partition coefficient, yet no equivalent quantitative relationships exist for metals. In the present study, we successfully related metal absorption rate constants to a metal specific property, the covalent index, and a species-characteristic, the ventilation rate. This quantitative relationship holds for a wide range of organisms and metals, i.e., 17 aquatic species and 10 metals, suggesting that a generic modeling approach of metal uptake kinetics is feasible for aquatic organisms. In contrast, elimination rate constants show no metal - specific character. Average, weight-corrected elimination rate constants are relatively similar among metals and species, suggesting that a single weight-corrected elimination rate constant can be used in bioaccumulation studies on aquatic species.

  11. Impacts of temperament on Nellore cattle: physiological responses, feedlot performance, and carcass characteristics.

    PubMed

    Francisco, C L; Resende, F D; Benatti, J M B; Castilhos, A M; Cooke, R F; Jorge, A M

    2015-11-01

    tended ( = 0.06) to have reduced serum insulin concentration compared with ADQ cattle. Both temperament groups had similar serum concentrations of IgA ( = 0.25) and total protein ( = 0.84). Cattle classified as EXC presented greater amounts ( = 0.05) of carcass bruises. In conclusion, an EXC temperament impaired feedlot performance, carcass characteristics, and meat quality traits in finishing Nellore cattle.

  12. Physiologic, metabolic, and muscle fiber type characteristics of musculus uvulae in sleep apnea hypopnea syndrome and in snorers.

    PubMed Central

    Sériès, F; Côté, C; Simoneau, J A; Gélinas, Y; St Pierre, S; Leclerc, J; Ferland, R; Marc, I

    1995-01-01

    Upper airway dilator muscles play an important role in the pathophysiology of sleep apnea hypopnea syndrome (SAHS). The mechanical and structural characteristics of these muscles remain unknown. The aim of this study was to compare the physiologic, metabolic, and fiber type characteristics of one upper airway dilator muscle (musculus uvulae, MU) in 11 SAHS and in seven nonapneic snorers. The different analyses were done on MU obtained during uvulo-palato-pharyngoplasty. Snorers and SAHS differed only in their apnea + hypopnea indices (11.5 +/- 5.9 and 34.2 +/- 14.6/h, respectively, mean +/- SD). Absolute twitch and tetanic tension production of MU was significantly greater in SAHS than in snorers while the fatigability index was similar in the two groups. Protein content and anaerobic enzyme activities of MU were significantly greater in SAHS than in snorers; no difference was observed for aerobic enzyme activities. The total muscle fiber cross-sectional area of MU was significantly higher in SAHS (2.2 +/- 0.9 mm2) than in snorers (1.1 +/- 0.7 mm2). The surface occupied by type IIA muscle fibers of MU was larger in SAHS (2.00 +/- 0.96) than in snorers (0.84 +/- 0.63 mm2). We conclude that the capacity for tension production and the anaerobic metabolic activity of MU are greater in SAHS than in snorers. PMID:7814616

  13. [Effects of simulated acid rain on oilseed rape (Brassica napus) physiological characteristics at flowering stage and yield].

    PubMed

    Cao, Chun-Xin; Zhou, Qin; Han, Liang-Liang; Zhang, Pei; Jiang, Hai-Dong

    2010-08-01

    A pot experiment was conducted to study the effects of different acidity simulated acid rain on the physiological characteristics at flowering stage and yield of oilseed rape (B. napus cv. Qinyou 9). Comparing with the control (pH 6.0), weak acidity (pH = 4.0-5.0) simulated acid rain stimulated the rape growth to some extent, but had less effects on the plant biomass, leaf chlorophyll content, photosynthetic characteristics, and yield. With the further increase of acid rain acidity, the plant biomass, leaf chlorophyll content, photosynthetic rate, antioxidative enzyme activities, and non-enzyme antioxidant contents all decreased gradually, while the leaf malonyldialdehyde (MDA) content and relative conductivity increased significantly. As the results, the pod number per plant, seed number per pod, seed weight, and actual yield decreased. However, different yield components showed different sensitivity to simulated acid rain. With the increasing acidity of simulated acid rain, the pod number per plant and the seed number per pod decreased significantly, while the seed weight was less affected.

  14. [Effects of simulated acid rain on oilseed rape (Brassica napus) physiological characteristics at flowering stage and yield].

    PubMed

    Cao, Chun-Xin; Zhou, Qin; Han, Liang-Liang; Zhang, Pei; Jiang, Hai-Dong

    2010-08-01

    A pot experiment was conducted to study the effects of different acidity simulated acid rain on the physiological characteristics at flowering stage and yield of oilseed rape (B. napus cv. Qinyou 9). Comparing with the control (pH 6.0), weak acidity (pH = 4.0-5.0) simulated acid rain stimulated the rape growth to some extent, but had less effects on the plant biomass, leaf chlorophyll content, photosynthetic characteristics, and yield. With the further increase of acid rain acidity, the plant biomass, leaf chlorophyll content, photosynthetic rate, antioxidative enzyme activities, and non-enzyme antioxidant contents all decreased gradually, while the leaf malonyldialdehyde (MDA) content and relative conductivity increased significantly. As the results, the pod number per plant, seed number per pod, seed weight, and actual yield decreased. However, different yield components showed different sensitivity to simulated acid rain. With the increasing acidity of simulated acid rain, the pod number per plant and the seed number per pod decreased significantly, while the seed weight was less affected. PMID:21043116

  15. Physiological regulation of evaporative water loss in endotherms: is the little red kaluta (Dasykaluta rosamondae) an exception or the rule?

    PubMed

    Withers, Philip C; Cooper, Christine E

    2014-06-01

    It is a central paradigm of comparative physiology that the effect of humidity on evaporative water loss (EWL) is determined for most mammals and birds, in and below thermoneutrality, essentially by physics and is not under physiological regulation. Fick's law predicts that EWL should be inversely proportional to ambient relative humidity (RH) and linearly proportional to the water vapour pressure deficit (Δwvp) between animal and air. However, we show here for a small dasyurid marsupial, the little kaluta (Dasykaluta rosamondae), that EWL is essentially independent of RH (and Δwvp) at low RH (as are metabolic rate and thermal conductance). These results suggest regulation of a constant EWL independent of RH, a hitherto unappreciated capacity of endothermic vertebrates. Independence of EWL from RH conserves water and heat at low RH, and avoids physiological adjustments to changes in evaporative heat loss such as thermoregulation. Re-evaluation of previously published data for mammals and birds suggests that a lesser dependence of EWL on RH is observed more commonly than previously thought, suggesting that physiological independence of EWL of RH is not just an unusual capacity of a few species, such as the little kaluta, but a more general capability of many mammals and birds.

  16. Physiological regulation of evaporative water loss in endotherms: is the little red kaluta (Dasykaluta rosamondae) an exception or the rule?

    PubMed Central

    Withers, Philip C.; Cooper, Christine E.

    2014-01-01

    It is a central paradigm of comparative physiology that the effect of humidity on evaporative water loss (EWL) is determined for most mammals and birds, in and below thermoneutrality, essentially by physics and is not under physiological regulation. Fick's law predicts that EWL should be inversely proportional to ambient relative humidity (RH) and linearly proportional to the water vapour pressure deficit (Δwvp) between animal and air. However, we show here for a small dasyurid marsupial, the little kaluta (Dasykaluta rosamondae), that EWL is essentially independent of RH (and Δwvp) at low RH (as are metabolic rate and thermal conductance). These results suggest regulation of a constant EWL independent of RH, a hitherto unappreciated capacity of endothermic vertebrates. Independence of EWL from RH conserves water and heat at low RH, and avoids physiological adjustments to changes in evaporative heat loss such as thermoregulation. Re-evaluation of previously published data for mammals and birds suggests that a lesser dependence of EWL on RH is observed more commonly than previously thought, suggesting that physiological independence of EWL of RH is not just an unusual capacity of a few species, such as the little kaluta, but a more general capability of many mammals and birds. PMID:24741015

  17. [Effects of different barnyardgrass species on grain yield of rice and their physiological characteristics under alternate wetting and drying irrigation].

    PubMed

    Zhang, Zi-chang; Li, Yong-feng; Yang, Xia; Gu, Tao; Li, Gui

    2015-11-01

    In order to investigate the influence of different barnyardgrass species on rice yield and physiological characteristics of rice, two rice cultivars, Liangyoupeijiu (an indica hybrid cultivar) and Nanjing 9108 (a japonica cultivar) , were employed to co-culture with four barnyardgrass species during the period from transplanting to maturity under alternate wetting and moderate drying ir- rigation condition. The treatments were separately designed as follow: weed free ( control) , rice with Echinochloa crusgalli var. mitis (T1), rice with E. crusgalli (T2), rice with E. crusgali var. zelayensis (T3) and rice with E. colonum (T4). The results showed that T1, T2, T3 and T4 treatments reduced the Liangyoupeijiu yield by 13.8%, 10.6%, 23.8% and 0.5%, but the corresponding yield loss of Nanjing 9108 could reach up to 45.5%, 36.9%, 60.7% and 15.1%, respectively. The results above showed that T1, T2 and T3 treatments all significantly reduced grain yield, and T4 treatment only reduced grain yield for Nanjing 9108 but not for Liangyoupeijiu. All treatments elevated malondialehyde contents of rice leaf, but the activities of peroxidase, catalase, superoxide dimutase, dry matter accumulation in maturity stage, root oxidation activities and contents of indole-3-acetic acid as well as zeatin + zeatin riboside in roots during rice grain filling stage were all decreased. The influence degree of four barnyardgrass against physiological indices of rice had the order of T3 > T1 >T2 > T4. It showed that the reductions in enzyme activities of antioxidant system, root oxidation activities, contents of indole-3-acetic acid, zeatin + zeatin riboside during grain filling stage and accumulation of dry matter in maturity as well as increase in contents of malondialehyde of rice during grain filling stage might be important reasons for grain yield reduction when grew with barnyardgrass. PMID:26915195

  18. Physiological and pathological left ventricular hypertrophy of comparable degree is associated with characteristic differences of in vivo hemodynamics.

    PubMed

    Oláh, Attila; Németh, Balázs Tamás; Mátyás, Csaba; Hidi, László; Lux, Árpád; Ruppert, Mihály; Kellermayer, Dalma; Sayour, Alex Ali; Szabó, Lilla; Török, Marianna; Meltzer, Anna; Gellér, László; Merkely, Béla; Radovits, Tamás

    2016-03-01

    Left ventricular (LV) hypertrophy is a physiological or pathological response of LV myocardium to increased cardiac load. We aimed at investigating and comparing hemodynamic alterations in well-established rat models of physiological hypertrophy (PhyH) and pathological hypertrophy (PaH) by using LV pressure-volume (P-V) analysis. PhyH and PaH were induced in rats by swim training and by abdominal aortic banding, respectively. Morphology of the heart was investigated by echocardiography. Characterization of cardiac function was completed by LV P-V analysis. In addition, histological and molecular biological measurements were performed. Echocardiography revealed myocardial hypertrophy of similar degree in both models, which was confirmed by post-mortem heart weight data. In aortic-banded rats we detected subendocardial fibrosis. Reactivation of fetal gene program could be observed only in the PaH model. PhyH was associated with increased stroke volume, whereas unaltered stroke volume was detected in PaH along with markedly elevated end-systolic pressure values. Sensitive indexes of LV contractility were increased in both models, in parallel with the degree of hypertrophy. Active relaxation was ameliorated in athlete's heart, whereas it showed marked impairment in PaH. Mechanical efficiency and ventriculo-arterial coupling were improved in PhyH, whereas they remained unchanged in PaH. Myocardial gene expression of mitochondrial regulators showed marked differences between PaH and PhyH. We provided the first comparative hemodynamic characterization of PhyH and PaH in relevant rodent models. Increased LV contractility could be observed in both types of LV hypertrophy; characteristic distinction was detected in diastolic function (active relaxation) and mechanoenergetics (mechanical efficiency), which might be explained by mitochondrial differences. PMID:26718969

  19. Physiological and pathological left ventricular hypertrophy of comparable degree is associated with characteristic differences of in vivo hemodynamics.

    PubMed

    Oláh, Attila; Németh, Balázs Tamás; Mátyás, Csaba; Hidi, László; Lux, Árpád; Ruppert, Mihály; Kellermayer, Dalma; Sayour, Alex Ali; Szabó, Lilla; Török, Marianna; Meltzer, Anna; Gellér, László; Merkely, Béla; Radovits, Tamás

    2016-03-01

    Left ventricular (LV) hypertrophy is a physiological or pathological response of LV myocardium to increased cardiac load. We aimed at investigating and comparing hemodynamic alterations in well-established rat models of physiological hypertrophy (PhyH) and pathological hypertrophy (PaH) by using LV pressure-volume (P-V) analysis. PhyH and PaH were induced in rats by swim training and by abdominal aortic banding, respectively. Morphology of the heart was investigated by echocardiography. Characterization of cardiac function was completed by LV P-V analysis. In addition, histological and molecular biological measurements were performed. Echocardiography revealed myocardial hypertrophy of similar degree in both models, which was confirmed by post-mortem heart weight data. In aortic-banded rats we detected subendocardial fibrosis. Reactivation of fetal gene program could be observed only in the PaH model. PhyH was associated with increased stroke volume, whereas unaltered stroke volume was detected in PaH along with markedly elevated end-systolic pressure values. Sensitive indexes of LV contractility were increased in both models, in parallel with the degree of hypertrophy. Active relaxation was ameliorated in athlete's heart, whereas it showed marked impairment in PaH. Mechanical efficiency and ventriculo-arterial coupling were improved in PhyH, whereas they remained unchanged in PaH. Myocardial gene expression of mitochondrial regulators showed marked differences between PaH and PhyH. We provided the first comparative hemodynamic characterization of PhyH and PaH in relevant rodent models. Increased LV contractility could be observed in both types of LV hypertrophy; characteristic distinction was detected in diastolic function (active relaxation) and mechanoenergetics (mechanical efficiency), which might be explained by mitochondrial differences.

  20. Climate influences thermal balance and water use in African and Asian elephants: physiology can predict drivers of elephant distribution.

    PubMed

    Dunkin, Robin C; Wilson, Dinah; Way, Nicolas; Johnson, Kari; Williams, Terrie M

    2013-08-01

    Elephant movement patterns in relation to surface water demonstrate that they are a water-dependent species. Thus, there has been interest in using surface water management to mitigate problems associated with localized elephant overabundance. However, the physiological mechanisms underlying the elephant's water dependence remain unclear. Although thermoregulation is likely an important driver, the relationship between thermoregulation, water use and climate has not been quantified. We measured skin surface temperature of and cutaneous water loss from 13 elephants (seven African, 3768±642 kg; six Asian, 3834±498 kg) and determined the contribution of evaporative cooling to their thermal and water budgets across a range of air temperatures (8-33°C). We also measured respiratory evaporative water loss and resting metabolic heat production on a subset of elephants (N=7). The rate of cutaneous evaporative water loss ranged between 0.31 and 8.9 g min(-1) m(-2) for Asian elephants and 0.26 and 6.5 g min(-1) m(-2) for African elephants. Simulated thermal and water budgets using climate data from Port Elizabeth, South Africa, and Okaukuejo, Namibia, suggested that the 24-h evaporative cooling water debt incurred in warm climates can be more than 4.5 times that incurred in mesic climates. This study confirms elephants are obligate evaporative coolers but suggests that classification of elephants as water dependent is insufficient given the importance of climate in determining the magnitude of this dependence. These data highlight the potential for a physiological modeling approach to predicting the utility of surface water management for specific populations.

  1. Climate influences thermal balance and water use in African and Asian elephants: physiology can predict drivers of elephant distribution.

    PubMed

    Dunkin, Robin C; Wilson, Dinah; Way, Nicolas; Johnson, Kari; Williams, Terrie M

    2013-08-01

    Elephant movement patterns in relation to surface water demonstrate that they are a water-dependent species. Thus, there has been interest in using surface water management to mitigate problems associated with localized elephant overabundance. However, the physiological mechanisms underlying the elephant's water dependence remain unclear. Although thermoregulation is likely an important driver, the relationship between thermoregulation, water use and climate has not been quantified. We measured skin surface temperature of and cutaneous water loss from 13 elephants (seven African, 3768±642 kg; six Asian, 3834±498 kg) and determined the contribution of evaporative cooling to their thermal and water budgets across a range of air temperatures (8-33°C). We also measured respiratory evaporative water loss and resting metabolic heat production on a subset of elephants (N=7). The rate of cutaneous evaporative water loss ranged between 0.31 and 8.9 g min(-1) m(-2) for Asian elephants and 0.26 and 6.5 g min(-1) m(-2) for African elephants. Simulated thermal and water budgets using climate data from Port Elizabeth, South Africa, and Okaukuejo, Namibia, suggested that the 24-h evaporative cooling water debt incurred in warm climates can be more than 4.5 times that incurred in mesic climates. This study confirms elephants are obligate evaporative coolers but suggests that classification of elephants as water dependent is insufficient given the importance of climate in determining the magnitude of this dependence. These data highlight the potential for a physiological modeling approach to predicting the utility of surface water management for specific populations. PMID:23842629

  2. Growth and physiological state of the microalgae Phaeodactylum tricornutum Bohlin (Bacillariophyta) in the water taken from peter the Great Bay

    NASA Astrophysics Data System (ADS)

    Zhuravel, Elena; Markina, Zhanna; Aizdaicher, Nina

    2009-09-01

    Bioassay of water from different parts of the Peter the Great Bay using microalgae P. tricornutum revealed that water quality influences not only the growth but also the physiological state of the microalgae. There was no difference in the cell size between control and experimental cultures. Inhibition of microalgae growth was revealed in water with low phosphates concentration, for example, in the Marine Reserve. High phosphates concentration and moderate organic pollution caused the stimulation of miñroalgae growth in such sites as the Tumen, the Partizanskaya and the Vtoraya rechka rivers mouths.

  3. Investigation on Heat Transfer Characteristics of Water Through Narrow Annulus

    SciTech Connect

    Guangyao Lu; Jing Wang

    2006-07-01

    A study is carried out to investigate the forced convective heat transfer characteristics of water through narrow annulus. For most works undertaken before were mainly concerned with the heat transfer characteristics of heat removal systems, the experiments herein are conducted to detect the heat transfer characteristics of heated fluid, as well as cooled fluid, flowing through narrow annulus. In the experiments, directions of flow include horizontal, upstream and downstream. The Reynolds number range, based on the annular hydraulic diameter, of 10 to 30,000 is covered in the experiments. During the experiments, the transitions from laminar to turbulent convective heat transfer are carefully observed. It is found that fully turbulent convective heat transfer is achieved at a lower Reynolds number in narrow annulus than that in larger tubes. When the Reynolds number is lower than 150, the heat transfer is degraded attributed to the slow flow rate and axial heat conduction. The experimental results indicate that the heat transfer characteristics of narrow annular flow are different from that of lager, more conventionally sized pipe flow. A convective heat transfer correlation is developed and the comparisons are made with the correlations of other works. (authors)

  4. Identification of Water Use Strategies at Early Growth Stages in Durum Wheat from Shoot Phenotyping and Physiological Measurements.

    PubMed

    Nakhforoosh, Alireza; Bodewein, Thomas; Fiorani, Fabio; Bodner, Gernot

    2016-01-01

    Modern imaging technology provides new approaches to plant phenotyping for traits relevant to crop yield and resource efficiency. Our objective was to investigate water use strategies at early growth stages in durum wheat genetic resources using shoot imaging at the ScreenHouse phenotyping facility combined with physiological measurements. Twelve durum landraces from different pedoclimatic backgrounds were compared to three modern check cultivars in a greenhouse pot experiment under well-watered (75% plant available water, PAW) and drought (25% PAW) conditions. Transpiration rate was analyzed for the underlying main morphological (leaf area duration) and physiological (stomata conductance) factors. Combining both morphological and physiological regulation of transpiration, four distinct water use types were identified. Most landraces had high transpiration rates either due to extensive leaf area (area types) or both large leaf areas together with high stomata conductance (spender types). All modern cultivars were distinguished by high stomata conductance with comparatively compact canopies (conductance types). Only few landraces were water saver types with both small canopy and low stomata conductance. During early growth, genotypes with large leaf area had high dry-matter accumulation under both well-watered and drought conditions compared to genotypes with compact stature. However, high stomata conductance was the basis to achieve high dry matter per unit leaf area, indicating high assimilation capacity as a key for productivity in modern cultivars. We conclude that the identified water use strategies based on early growth shoot phenotyping combined with stomata conductance provide an appropriate framework for targeted selection of distinct pre-breeding material adapted to different types of water limited environments. PMID:27547208

  5. Effect of drinking water temperature on physiological variables of crossbred dairy cattle at high altitude temperate region of Himalayas

    PubMed Central

    Golher, D. M.; Thirumurugan, P.; Patel, B. H. M.; Upadhyay, V. K.; Sahu, S.; Gaur, G. K.; Bhoite, S. H.

    2015-01-01

    Aim: The objective of study was to investigate the effects of drinking water on certain physiological parameters such as heart rate (HR), respiration rate (RR), rectal temperature (RT) and, ruminal motility (RM). Materials and Methods: The experiment was carried out on 18 farm bred lactating crossbred cows. The animals selected for the study were divided into three groups of six animals each on the basis of milk yield and parity and were allotted to three treatment group of six each such as ambient drinking water temperature at 10.25±0.28°C (ambient water, T1), drinking water temperature at 15-20°C (T2) and drinking water temperature at 35-40°C (T3). All the managemental practices were kept similar during experiment except drinking water temperatures physiological variables such as HR, RR, RT, and RM of the individual cow was measured and recorded twice in a day at 800 h and again at 1400 h two consecutive days in a week 15 min after providing drinking water. Result: HR and RR at morning and at evening recorded were within the normal physiological level for all the treatment groups. However, RT at morning was comparable in all the treatments whereas at evening it was significantly (p<0.01) higher for cows consuming in T2 and in T3 than cows consumed (T1). The RM during morning among the treatments were non-significant as compared to the rumen motility at evening was significantly higher for (T1) and (T2) than for cows in (T3). Conclusion: It can be concluded that offering warm drinking water at 35-40°C to crossbred lactating dairy cow is beneficial during winter at high altitude temperate region. PMID:27047019

  6. Identification of Water Use Strategies at Early Growth Stages in Durum Wheat from Shoot Phenotyping and Physiological Measurements

    PubMed Central

    Nakhforoosh, Alireza; Bodewein, Thomas; Fiorani, Fabio; Bodner, Gernot

    2016-01-01

    Modern imaging technology provides new approaches to plant phenotyping for traits relevant to crop yield and resource efficiency. Our objective was to investigate water use strategies at early growth stages in durum wheat genetic resources using shoot imaging at the ScreenHouse phenotyping facility combined with physiological measurements. Twelve durum landraces from different pedoclimatic backgrounds were compared to three modern check cultivars in a greenhouse pot experiment under well-watered (75% plant available water, PAW) and drought (25% PAW) conditions. Transpiration rate was analyzed for the underlying main morphological (leaf area duration) and physiological (stomata conductance) factors. Combining both morphological and physiological regulation of transpiration, four distinct water use types were identified. Most landraces had high transpiration rates either due to extensive leaf area (area types) or both large leaf areas together with high stomata conductance (spender types). All modern cultivars were distinguished by high stomata conductance with comparatively compact canopies (conductance types). Only few landraces were water saver types with both small canopy and low stomata conductance. During early growth, genotypes with large leaf area had high dry-matter accumulation under both well-watered and drought conditions compared to genotypes with compact stature. However, high stomata conductance was the basis to achieve high dry matter per unit leaf area, indicating high assimilation capacity as a key for productivity in modern cultivars. We conclude that the identified water use strategies based on early growth shoot phenotyping combined with stomata conductance provide an appropriate framework for targeted selection of distinct pre-breeding material adapted to different types of water limited environments. PMID:27547208

  7. Thermodynamic characteristics of cyclohexanone distribution between extractants and water

    SciTech Connect

    Vozin, V.G.; Diyarov, I.N.; Gainullin, I.F.

    1986-01-10

    The authors have determined the thermodynamic characteristics of cyclohexanone distribution between extractants and water, making it possible to estimate the effectiveness of its separation by the extraction method. The extractants studied were hexane, heptane, octane, benzene, toluene, ethylbenzene, ethyl acetate, and butyl acetate. Analysis of the results shows that the partition ratio increases with increase of the equilibrium concentrations of cyclohexanone in the coexisting phases, indicating association of the molecules of the distributed substance in the extractant phase. The foregoing leads to the conclusion that aromatic hydrocarbons and acetate esters are superior to paraffins in extractive properties.

  8. Thrust Characteristics of Water Rocket and Their Improvement

    NASA Astrophysics Data System (ADS)

    Watanabe, Rikio; Tomita, Nobuyuki; Takemae, Toshiaki

    The propulsive characteristics of water rockets are analyzed theoretically and experimentally. The unsteady thrust force acting on a PET bottle and the air pressure inside the bottle are measured simultaneously by the thrust test stand we have developed. The semi-empirical thrust history is obtained utilizing the air pressure history and it is compared with the measured thrust history. The results show qualitative agreement. The observation of the flow inside bottle by a high-speed video camera shows that the air precedes water when it is about to be discharged entirely. We have developed a flow regulator attached to the nozzle cap to reduce the precursor air discharge that is considered as a result of the swirling flow inside the bottle. The experimental results show that the air discharge and the body vibration are suppressed effectively.

  9. Measurement of "turbidity" and related characteristics of natural waters

    USGS Publications Warehouse

    Pickering, R.J.

    1976-01-01

    The U.S. Geological Survey, Water Resources Division has adopted the following principles to be used in selecting methods for the measurement of light transmitting characteristics of natural waters: (1) standard instruments and methods are to be adopted to measure and report in optical units, avoiding ' turbidity ' as a quantitative measure; (2) reporting of ' turbidity ' in JTU 's, Hellige units, severity, or NTU 's will be phased out; (3) the basis for estimations of sediment concentrations based on light measurements must be documented adequately; and (4) use of transparency measurement by Secchi disk is not changed, although light transmittance may prove to be more precise means of obtaining the same information. A schedule has been established to implement new methods beginning October 1, 1976, and with the transition to be completed at all stations by October 1, 1977. Provisions are provided to meet requirements of cooperators who have legal requirements for ' turbidity ' data. (Woodard-USGS)

  10. Within-catchment variation in regulation of water use by eucalypts, and the roles of stomatal anatomy and physiology

    NASA Astrophysics Data System (ADS)

    Gharun, Mana; Turnbull, Tarryn; Adams, Mark

    2014-05-01

    Understanding how environmental cues impact water use of forested catchments is crucial for accurate calculation of water balance and effective catchment management in terrestrial ecosystems. We characterised structural and physiological properties of leaves and canopies of Eucalyptus delegatensis, E. pauciflora and E. radiata, the most common species in high-country catchments in temperate Australia. These properties were related to whole-tree water transport to assess differences in water use strategies among the three species. Stomatal conductance, instantaneous transpiration efficiency, stomatal occlusion (through cuticular ledges) and leaf area index differed significantly among species. Whole-tree water use of all species was strongly coupled to changes in vapour pressure deficit (VPD) and photosynthetically active radiation (Q), yet stomatal closure reduced water transport at VPD > 1 kPa in all species, even when soil water was not limiting. The observed differences in leaf traits and related water use strategies reflect species-specific adaptations to dominant environmental conditions within the landscape matrix of catchments. The generalist E. radiata seems to follow an opportunistic, while the two more spatially restricted species have adopted a pessimistic water use strategy. Catchment-scale models of carbon and water fluxes will need to reflect such variation in structure and function, if they are to fully capture species effects on water balance and yield.

  11. The Effect of Phenazine-1-Carboxylic Acid on the Morphological, Physiological, and Molecular Characteristics of Phellinus noxius.

    PubMed

    Huang, Huazhi; Sun, Longhua; Bi, Keke; Zhong, Guohua; Hu, Meiying

    2016-05-11

    In this study, the effect of phenazine-1-carboxylic acid (PCA) on morphological, physiological, and molecular characteristics of Phellinus noxius has been investigated, and the potential antifungal mechanism of PCA against P. noxius was also explored. The results revealed that PCA showed in vitro antifungal potential against P. noxius and completely inhibited P. noxius hyphae at concentrations >40 μg/mL. PCA inhibited both mycelial growth and the loss of mycelial biomass in vitro in a dose-dependent manner. Morphological changes in PCA-treated P. noxius hyphae, such as irregularly swollen mycelia as well as short hyphae with increased septation and less branching, were observed by optical microscopy. The intracellular reactive oxygen species (ROS) levels were significantly increased in PCA-treated P. noxius cells as compared to control groups. Induced hyperpolarization of the mitochondrial membrane potential (MMP), repressed superoxide dismutase (SOD) activity and up-regulated gene expression of seven tested genes were also found in PCA-treated P. noxius groups. Thus, the present results suggested that the mechanism of action of PCA against P. noxius might be attributed to direct damage of mycelium and high intracellular ROS production, and indirect induction of genes involved in cell detoxification, oxidation-reduction process, and electron transport of the respiratory chain.

  12. Physiological characteristics of National Collegiate Athletic Association Division I ice hockey players and their relation to game performance.

    PubMed

    Peyer, Karissa L; Pivarnik, James M; Eisenmann, Joey C; Vorkapich, Michael

    2011-05-01

    Previous ice hockey research has focused on physiological profiles and determinants of skating speed, but few studies have examined the association of preseason player evaluations with a measure of season-long performance. Understanding which tests are most predictive of player performance could help coaches organize practice and training more effectively. The purpose of this study was to describe physical characteristics and skill levels of 24 members of an NCAA Division I men's ice hockey team and relate them to game performance over the course of a season as measured by plus/minus (+/-) score. Subjects performed a battery of preseason tests including treadmill maximal aerobic capacity, body fat, leg press, push-ups, bench press, chin-ups, and sprinting ability both on and off ice. Pearson and Spearman correlations were used to examine correlations between preseason measures and +/- score. One coach also subjectively grouped the top and bottom 6 players, and analysis of variance was used to examine any differences in preseason measures and +/- score between these 2 groups. Leg press, chin-ups, bench press, and repeat sprint performance were significantly correlated with +/- score (r = 0.554, 0.462, 0.499, and -0.568, respectively). Teams with limited time and resources may choose to perform these tests to evaluate player potential efficiently. Only +/- score differed between top and bottom players suggesting that +/- accurately reflected the coach's perception of player success in this sample. PMID:21478763

  13. Effects of nickel hyperaccumulation on physiological characteristics of Alyssum murale grown on metal contaminated waste amended soil.

    PubMed

    Sellami, Rim; Gharbi, Fatma; Rejeb, Saloua; Rejeb, Mohamed Néjib; Henchi, Belgacem; Echevarria, Guillaume; Morel, Jean-Louis

    2012-07-01

    A pot experiment was conducted to investigate the effect of nickel concentration on physiological characteristics of Alyssum murale when grown in a soil mixed with sewage sludge (at the rate of 2.8%). Two types of sludge were used: agricultural sewage sludge (S1) and industrial sewage sludge with an increasing nickel concentration (S2, S3, and S4). Results showed that Ni in shoots was higher than Ni in roots. A. murale is able to concentrate up to 12730 mg/kg Ni in leaves. The highest dry matter yield was observed with plants grown with agricultural sewage sludge. An addition of S2 and S3 increased shoot biomass. However, application of S4 reduced 40% shoot dry weight as compared to the control Ni treatment did not affect all chlorophyll fluorescence parameters. The F(v)/F(m) ratio was stable between Ni treatments. Photosynthesis rate (A) increased with agricultural sewage sludge, but remained stable with variable Ni rates from the industrial sludge. The chlorophyll content increased with S1, S2 and S3 but it remains constant with S4 when compared to the control Therefore, high nickel concentration did not affect the function of the photosynthetic machine of A. murale.

  14. Spectral characteristics analysis of red tide water in mesocosm experiment

    NASA Astrophysics Data System (ADS)

    Cui, Tingwei; Zhang, Jie; Zhang, Hongliang; Ma, Yi; Gao, Xuemin

    2003-05-01

    Mesocosm ecosystem experiment with seawater enclosed of the red tide was carried out from July to September 2001. We got four species of biology whose quantities of bion are dominant in the red tide. During the whole process from the beginning to their dying out for every specie, in situ spectral measurements were carried out. After data processing, characteristic spectra of red tide of different dominant species are got. Via comparison and analysis of characteristics of different spectra, we find that in the band region between 685 and 735 nanometers, spectral characteristics of red tide is apparently different from that of normal water. Compared to spectra of normal water, spectra of red tide have a strong reflectance peak in the above band region. As to spectra of red tide dominated by different species, the situations of reflectance peaks are also different: the second peak of Mesodinium rubrum spectrum lies between 726~732 nm, which is more than 21nm away from the other dominant species spectra"s Leptocylindrus danicus"s second spectral peak covers 686~694nm; that of Skeletonema costatum lies between 691~693 nm. Chattonella marina"s second spectral peak lies about 703~705 nm. Thus we can try to determine whether red tide has occurred according to its spectral data. In order to monitor the event of red tide and identify the dominant species by the application of the technology of hyperspectral remote sensing, acquiring spectral data of different dominant species of red tide as much as possible becomes a basic work to be achieved for spectral matching, information extraction and so on based on hyperspectral data.

  15. Sensitivity of Terrestrial Water and Energy Budgets to CO2-Physiological Forcing: An Investigation Using an Offline Land Model

    NASA Technical Reports Server (NTRS)

    Gopalakrishnan, Ranjith; Bala, Govindsamy; Jayaraman, Mathangi; Cao, Long; Nemani, Ramakrishna; Ravindranath, N. H.

    2011-01-01

    Increasing concentrations of atmospheric carbon dioxide (CO2) influence climate by suppressing canopy transpiration in addition to its well-known greenhouse gas effect. The decrease in plant transpiration is due to changes in plant physiology (reduced opening of plant stomata). Here, we quantify such changes in water flux for various levels of CO2 concentrations using the National Center for Atmospheric Research s (NCAR) Community Land Model. We find that photosynthesis saturates after 800 ppmv (parts per million, by volume) in this model. However, unlike photosynthesis, canopy transpiration continues to decline at about 5.1% per 100 ppmv increase in CO2 levels. We also find that the associated reduction in latent heat flux is primarily compensated by increased sensible heat flux. The continued decline in canopy transpiration and subsequent increase in sensible heat flux at elevated CO2 levels implies that incremental warming associated with the physiological effect of CO2 will not abate at higher CO2 concentrations, indicating important consequences for the global water and carbon cycles from anthropogenic CO2 emissions. Keywords: CO2-physiological effect, CO2-fertilization, canopy transpiration, water cycle, runoff, climate change 1.

  16. Microcontaminant accumulation, physiological condition and bilateral asymmetry in zebra mussels (Dreissena polymorpha) from clean and contaminated surface waters.

    PubMed

    Voets, Judith; Talloen, Willem; de Tender, Tineke; van Dongen, Stefan; Covaci, Adrian; Blust, Ronny; Bervoets, Lieven

    2006-09-12

    Chemical and biological monitoring of pollution in the aquatic environment is essential to assess the quality of surface waters. Zebra mussels (Dreissena polymorpha) have been used extensively to monitor pollution in freshwater environments, especially in bioaccumulation studies, whereby pollutant levels in tissues have been used as a measure of exposure. However, there is a need for good biomarkers that reflect the impact of exposure to pollutants. Bilateral asymmetry, commonly used as a measure of developmental instability, has a high potential as a biomarker to monitor stress caused by pollution. Nevertheless, until recently, no studies have evaluated bilateral asymmetry as a biomarker in zebra mussels. Biomarkers related to the energy metabolism may give a good indication of the physiological cost of exposure to pollution. In this study, we investigated whether the physiological condition (energy reserves and condition indices) and bilateral asymmetry of shells of zebra mussels are potentially useful biomarkers to monitor the impact of micropollution, such as trace metals, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and di(p-chlorophenyl) dichloroethylene (p,p'-DDE) in the freshwater environment. Bilateral asymmetry of the zebra mussel shells was examined with respect to levels of pollutants accumulated in the mussels and compared to the physiological condition of the mussels. Levels of PCBs and several trace metals (especially Cd, Cu and Zn) were very high in four of the six sampling locations and in some locations the physiological condition of the mussels was significantly depressed. Nevertheless we did not find any relation (on individual or population level) with bilateral asymmetry of zebra mussel shells. Therefore our results suggest that bilateral asymmetry of zebra mussel shells is not a good measure for the impact of pollution in freshwater ecosystems. The energy reserves and condition indices, on the other hand, gave a

  17. Molecular mechanisms underlying the physiological responses of the cold-water coral Desmophyllum dianthus to ocean acidification

    NASA Astrophysics Data System (ADS)

    Carreiro-Silva, M.; Cerqueira, T.; Godinho, A.; Caetano, M.; Santos, R. S.; Bettencourt, R.

    2014-06-01

    Cold-water corals (CWCs) are thought to be particularly vulnerable to ocean acidification (OA) due to increased atmospheric pCO2, because they inhabit deep and cold waters where the aragonite saturation state is naturally low. Several recent studies have evaluated the impact of OA on organism-level physiological processes such as calcification and respiration. However, no studies to date have looked at the impact at the molecular level of gene expression. Here, we report results of a long-term, 8-month experiment to compare the physiological responses of the CWC Desmophyllum dianthus to OA at both the organismal and gene expression levels under two pCO2/pH treatments: ambient pCO2 (460 μatm, pHT = 8.01) and elevated pCO2 (997 μatm, pHT = 7.70). At the organismal level, no significant differences were detected in the calcification and respiration rates of D. dianthus. Conversely, significant differences were recorded in gene expression profiles, which showed an up-regulation of genes involved in cellular stress (HSP70) and immune defence (mannose-binding c-type lectin). Expression of alpha-carbonic anhydrase, a key enzyme involved in the synthesis of coral skeleton, was also significantly up-regulated in corals under elevated pCO2, indicating that D. dianthus was under physiological reconditioning to calcify under these conditions. Thus, gene expression profiles revealed physiological impacts that were not evident at the organismal level. Consequently, understanding the molecular mechanisms behind the physiological processes involved in a coral's response to elevated pCO2 is critical to assess the ability of CWCs to acclimate or adapt to future OA conditions.

  18. Life under water: physiological adaptations to diving and living at sea.

    PubMed

    Castellini, Michael

    2012-07-01

    This review covers the field of diving physiology by following a chronological approach and focusing heavily on marine mammals. Because the study of modern diving physiology can be traced almost entirely to the work of Laurence Irving in the 1930s, this particular field of physiology is different than most in that it did not derive from multiple laboratories working at many locations or on different aspects of a similar problem. Because most of the physiology principles still used today were first formulated by Irving, it is important to the study of this field that the sequence of thought is examined as a progression of theory. The review covers the field in roughly decadal blocks and traces ideas as they were first suggested, tested, modified and in some cases, abandoned. Because diving physiology has also been extremely dependent on new technologies used in the development of diving recorders, a chronological approach fits well with advances in electronics and mechanical innovation. There are many species that dive underwater as part of their natural behavior, but it is mainly the marine mammals (seals, sea lions, and whales) that demonstrate both long duration and dives to great depth. There have been many studies on other diving species including birds, snakes, small aquatic mammals, and humans. This work examines these other diving species as appropriate and a listing of reviews and relevant literature on these groups is included at the end.

  19. Definition and characteristics of the water abundant season in Korea

    NASA Astrophysics Data System (ADS)

    Park, So-Ra; Oh, Su-Bin; Byun, Hi-Ryong

    2015-04-01

    In contrast to the normal seasons that are classified by the distribution of temperature and precipitation, this study defines a new concept of the water abundant season (WAS) when water is more abundant than in other seasons. We investigated its characteristics on 60 stations in Korea, and compared it with Changma (the rainy season). In this study, Available Water Resources Index (AWRI), which is a summed daily precipitation accumulated for more than 365 days with a time-dependent reduction function and reflects the current water condition, was used to quantify the water amount. In addition, the median value of 30 year's daily AWRI was used as the criterion value dividing WAS from other seasons. The results show that the terminologies on water resources have changed from qualitative concepts such as abundance, deficit, and continuous rainfall, to quantitative values using AWRI. In detail, it was known that the WAS in Korea starts on 2 July and ends on 25 December, lasting for 176 days. The onset date of WAS in Korea is getting earlier, with a trend of 2.9 days/decade. The end date does later with a delay of 7.5 days/decade, and the duration is increasing at 10.4 days/decade. We looked at the WAS by stations and saw, on average, that 14 June was the earliest onset date in Seogwipo and 29 July was the latest one in Sokcho, representing a difference of 45 days. The earliest end date was in Tongyeong at 5 December and the latest one is in Uljin at 16 January of the following year, a difference of 41 days. Tongyeong had the shortest (166 days) WAS duration and Uljin had the longest (207 days) on average. The big spatial differences of the criterion values per station were detected and quantified. The largest criterion value for WAS were recorded in Seongsan with 270.7 mm, which is almost double of the smallest value, which was recorded in Uiseong (135.9 mm). Comparing WAS with the Changma (the rainy season in Korea) showed that the onset date of WAS is close to that of

  20. Eco-physiological response of Populus euphratica Oliv. to water release of the lower reaches of the Tarim River, China

    NASA Astrophysics Data System (ADS)

    Wang, Q.; Ruan, X.; Chen, Y. N.; Li, W. H.

    2007-10-01

    Eco-physiological and plant performance responses and acclimation of Populus euphratica Oliv. to water release of the lower reaches of Tarim River, China were investigated. Three representative areas and 15 transects were selected along the lower reaches of the Tarim River. The groundwater level and salt content as well as plant performance and the contents of proline, soluble sugar, and plant endogenous hormone (ABA, CTK) in leaves were monitored and analyzed before- and after-water release. The groundwater level was raised in different areas and transects by the water release program. The physiological stress to P. euphratica decreased after the water release. Our results suggested that the groundwater level in the studied region changed from -3.15 to -4.12 m, salt content of the groundwater from 67.15 to 72.65 mM, the proline content from 9.28 to 11.06 mM, the soluble sugar content from 224.71 to 252.16 mM, the ABA content from 3.59 to 5.01 ng/(g FW), and the CK content from 4.01 to 4.56 ng/(g FW)- for the optimum growth and recover of P. euphratica indicated by the plant performance parameters, and the efficiency of water release was the highest.

  1. Physiological impacts of ABA-JA interactions under water-limitation.

    PubMed

    de Ollas, Carlos; Dodd, Ian C

    2016-08-01

    Plant responses to drought stress depend on highly regulated signal transduction pathways with multiple interactions. This complex crosstalk can lead to a physiological outcome of drought avoidance or tolerance/resistance. ABA is the principal mediator of these responses due to the regulation of stomatal closure that determines plant growth and survival, but also other strategies of drought resistance such as osmotic adjustment. However, other hormones such as JA seem responsible for regulating a subset of plant responses to drought by regulating ABA biosynthesis and accumulation and ABA-dependent signalling, but also by ABA independent pathways. Here, we review recent reports of ABA-JA hormonal and molecular interactions within a physiological framework of drought tolerance. Understanding the physiological significance of this complex regulation offers opportunities to find strategies of drought tolerance that avoid unwanted side effects that limit growth and yield, and may allow biotechnological crop improvement. PMID:27299601

  2. Physiological impacts of ABA-JA interactions under water-limitation.

    PubMed

    de Ollas, Carlos; Dodd, Ian C

    2016-08-01

    Plant responses to drought stress depend on highly regulated signal transduction pathways with multiple interactions. This complex crosstalk can lead to a physiological outcome of drought avoidance or tolerance/resistance. ABA is the principal mediator of these responses due to the regulation of stomatal closure that determines plant growth and survival, but also other strategies of drought resistance such as osmotic adjustment. However, other hormones such as JA seem responsible for regulating a subset of plant responses to drought by regulating ABA biosynthesis and accumulation and ABA-dependent signalling, but also by ABA independent pathways. Here, we review recent reports of ABA-JA hormonal and molecular interactions within a physiological framework of drought tolerance. Understanding the physiological significance of this complex regulation offers opportunities to find strategies of drought tolerance that avoid unwanted side effects that limit growth and yield, and may allow biotechnological crop improvement.

  3. [Complex effects of simulated acid rain and Cu on the physiological characteristics of Paulownia fortunei and its detoxification mechanism].

    PubMed

    Wang, Jiang; Zhang, Chong-Bang; Ke, Shi-Sheng; Qian, Bao-Ying

    2010-03-01

    A pot experiment was conducted to study the effects of simulated acid rain (pH 4.0, 5.0) and Cu (0-200 mg x kg(-1)) on the physiological characteristics of Paulownia fortunei and its detoxification mechanism. With no Cu addition, the leaf chlorophyll, carotenoid, O2 division by, H2O2, and MDA contents of P. fortunei had no significant differences between the two acid rain treatments. However, with the addition of 100 and 200 mg Cu x kg(-1), the chlorophyll and carotenoid contents of treatment pH 4.0 were lower, while the O2 divided by, H2O2 and MDA contents were higher thanthose of treatment pH 5.0. The chlorophyll a/b ratio of treatments Cu was higher than that of the control. The leaf Cu content decreased obviously with the increasing acidity of stimulated acid rain, but the root Cu content was in reverse. With increasing Cu addition, both the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and the total contents of phytochelatins (PCs) and glutathione (GSH) in treatment pH 5.0 increased, while the activities of SOD, POD, CAT and APX in treatment pH 4.0 decreased after an initial increase, and the total contents of glutathione (GSH) decreased greatly in treatment 200 mg Cu x kg(-1). All of these demonstrated that the oxidative stress of high Cu concentration to P. fortunei was aggravated by stimulated acid rain. PMID:20560310

  4. Effects of ramp slope on physiological characteristic and performance time of healthy adults propelling and pushing wheelchairs

    PubMed Central

    Choi, Young Oh; Lee, Ho Young; Lee, Myoung Hee; Kwon, Oh Hyun

    2015-01-01

    [Purpose] This study examined the effects of ramp slope (1:12, 1:10, 1:8, and 1:6) on physiological characteristics and performance times of wheelchair users and the performance times of caregivers to determine which slope would be the best for wheelchairs, in order to propose a ramp slope that incorporates a universal design. [Subjects and Methods] Twenty-four healthy subjects were enrolled in this study. Fifteen of these subjects also volunteered to participate as caregivers. A wooden ramp with an adjustable slope was constructed. As manual wheelchair users, the participants performed propulsion of a wheelchair up the ramp at a self-selected pace. Four ramp slopes (1:12, 1:10, 1:8, and 1:6) were used, and the participants sequentially ascended them in order from the gentlest to the steepest slope. The caregivers also pushed a wheelchair up the ramp at a self-selected pace. The blood pressure and pulse of participants after the ascent, as well as the performance times of the caregivers and manual wheelchair users, were measured on each of the different ramp slopes. The measured data, pulse, blood pressure, and performance time, were analyzed using repeated ANOVA. [Results] Systolic blood pressure was significantly higher after ascending the 1:6 slope than after ascending the 1:12 and 1:8 slopes. Diastolic blood pressure was significantly higher after ascending the 1:6 slope than after ascending the 1:12 and 1:8 slopes. The participants’ pulses tended to increase significantly with an increase in slope. An assessment of the propulsion performance times revealed significant differences among the slopes. [Conclusion] Considering the results of the wheelchair users and caregivers, the 1:12 and 1:10 slopes are suitable ramp slopes for wheelchairs. PMID:25642025

  5. Effects of ramp slope on physiological characteristic and performance time of healthy adults propelling and pushing wheelchairs.

    PubMed

    Choi, Young Oh; Lee, Ho Young; Lee, Myoung Hee; Kwon, Oh Hyun

    2015-01-01

    [Purpose] This study examined the effects of ramp slope (1:12, 1:10, 1:8, and 1:6) on physiological characteristics and performance times of wheelchair users and the performance times of caregivers to determine which slope would be the best for wheelchairs, in order to propose a ramp slope that incorporates a universal design. [Subjects and Methods] Twenty-four healthy subjects were enrolled in this study. Fifteen of these subjects also volunteered to participate as caregivers. A wooden ramp with an adjustable slope was constructed. As manual wheelchair users, the participants performed propulsion of a wheelchair up the ramp at a self-selected pace. Four ramp slopes (1:12, 1:10, 1:8, and 1:6) were used, and the participants sequentially ascended them in order from the gentlest to the steepest slope. The caregivers also pushed a wheelchair up the ramp at a self-selected pace. The blood pressure and pulse of participants after the ascent, as well as the performance times of the caregivers and manual wheelchair users, were measured on each of the different ramp slopes. The measured data, pulse, blood pressure, and performance time, were analyzed using repeated ANOVA. [Results] Systolic blood pressure was significantly higher after ascending the 1:6 slope than after ascending the 1:12 and 1:8 slopes. Diastolic blood pressure was significantly higher after ascending the 1:6 slope than after ascending the 1:12 and 1:8 slopes. The participants' pulses tended to increase significantly with an increase in slope. An assessment of the propulsion performance times revealed significant differences among the slopes. [Conclusion] Considering the results of the wheelchair users and caregivers, the 1:12 and 1:10 slopes are suitable ramp slopes for wheelchairs. PMID:25642025

  6. [Complex effects of simulated acid rain and Cu on the physiological characteristics of Paulownia fortunei and its detoxification mechanism].

    PubMed

    Wang, Jiang; Zhang, Chong-Bang; Ke, Shi-Sheng; Qian, Bao-Ying

    2010-03-01

    A pot experiment was conducted to study the effects of simulated acid rain (pH 4.0, 5.0) and Cu (0-200 mg x kg(-1)) on the physiological characteristics of Paulownia fortunei and its detoxification mechanism. With no Cu addition, the leaf chlorophyll, carotenoid, O2 division by, H2O2, and MDA contents of P. fortunei had no significant differences between the two acid rain treatments. However, with the addition of 100 and 200 mg Cu x kg(-1), the chlorophyll and carotenoid contents of treatment pH 4.0 were lower, while the O2 divided by, H2O2 and MDA contents were higher thanthose of treatment pH 5.0. The chlorophyll a/b ratio of treatments Cu was higher than that of the control. The leaf Cu content decreased obviously with the increasing acidity of stimulated acid rain, but the root Cu content was in reverse. With increasing Cu addition, both the activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX) and the total contents of phytochelatins (PCs) and glutathione (GSH) in treatment pH 5.0 increased, while the activities of SOD, POD, CAT and APX in treatment pH 4.0 decreased after an initial increase, and the total contents of glutathione (GSH) decreased greatly in treatment 200 mg Cu x kg(-1). All of these demonstrated that the oxidative stress of high Cu concentration to P. fortunei was aggravated by stimulated acid rain.

  7. [Effects of exogenous nitric oxide on physiological characteristics of longan (Dimocarpus longana) seedlings under acid rain stress].

    PubMed

    Liu, Jian-fu; Wang, Ming-yuan; Yang, Chen; Zhu, Ai-jun

    2013-08-01

    This paper studied the effects of exogenous nitric oxide donor sodium nitroprusside (SNP) on the chlorophyll content, antioxidant enzyme activities, and osmotic regulation substances of longan (Dimocarpus longana 'Fuyan') seedlings under acid rain (pH 3.0) stress. Under the acid rain stress, the seedling leaf superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and chlorophyll, soluble protein and soluble sugar contents decreased obviously, while the leaf malondialdedyde content had a remarkable increase, suggesting the toxic effect of the acid rain on the seedlings. Exogenous nitric oxide had dual nature on the physiological characteristics of longan seedlings under acid rain stress. Applying 0.1-0.5 mmol x L(-1) of SNP improved the SOD, POD and CAT activities and the chlorophyll, soluble protein and soluble sugar contents significantly, and decreased the malondialdedyde content. Low concentrations SNP reduced the oxidative damage caused by the acid rain stress, and 0.5 mmol x L(-1) of SNP had the best effect. Under the application of 0.5 mmol x L(-1) of SNP, the total chlorophyll, soluble protein, and soluble sugar contents and the SOD, POD and CAT activities increased by 76.0%, 107.0%, 216.1%, 150. 0%, 350.9% and 97.1%, respectively, and the malondialdedyde content decreased by 46.4%. It was suggested that low concentration (0.1-0.5 mmol x L(-1)) SNP could alleviate the toxic effect of acid rain stress on longan seedlings via activating the leaf antioxidant enzyme activities and reducing oxidative stress, while high concentration SNP (1.0 mmol x L(-1)) lowered the mitigation effect.

  8. [Effects of exogenous nitric oxide on physiological characteristics of longan (Dimocarpus longana) seedlings under acid rain stress].

    PubMed

    Liu, Jian-fu; Wang, Ming-yuan; Yang, Chen; Zhu, Ai-jun

    2013-08-01

    This paper studied the effects of exogenous nitric oxide donor sodium nitroprusside (SNP) on the chlorophyll content, antioxidant enzyme activities, and osmotic regulation substances of longan (Dimocarpus longana 'Fuyan') seedlings under acid rain (pH 3.0) stress. Under the acid rain stress, the seedling leaf superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and chlorophyll, soluble protein and soluble sugar contents decreased obviously, while the leaf malondialdedyde content had a remarkable increase, suggesting the toxic effect of the acid rain on the seedlings. Exogenous nitric oxide had dual nature on the physiological characteristics of longan seedlings under acid rain stress. Applying 0.1-0.5 mmol x L(-1) of SNP improved the SOD, POD and CAT activities and the chlorophyll, soluble protein and soluble sugar contents significantly, and decreased the malondialdedyde content. Low concentrations SNP reduced the oxidative damage caused by the acid rain stress, and 0.5 mmol x L(-1) of SNP had the best effect. Under the application of 0.5 mmol x L(-1) of SNP, the total chlorophyll, soluble protein, and soluble sugar contents and the SOD, POD and CAT activities increased by 76.0%, 107.0%, 216.1%, 150. 0%, 350.9% and 97.1%, respectively, and the malondialdedyde content decreased by 46.4%. It was suggested that low concentration (0.1-0.5 mmol x L(-1)) SNP could alleviate the toxic effect of acid rain stress on longan seedlings via activating the leaf antioxidant enzyme activities and reducing oxidative stress, while high concentration SNP (1.0 mmol x L(-1)) lowered the mitigation effect. PMID:24380343

  9. The Characteristics of Sleepiness During Real Driving at Night—A Study of Driving Performance, Physiology and Subjective Experience

    PubMed Central

    Sandberg, David; Anund, Anna; Fors, Carina; Kecklund, Göran; Karlsson, Johan G.; Wahde, Mattias; Åkerstedt, Torbjörn

    2011-01-01

    Study Objectives: Most studies of sleepy driving have been carried out in driving simulators. A few studies of real driving are available, but these have used only a few sleepiness indicators. The purpose of the present study was to characterize sleepiness in several indicators during real driving at night, compared with daytime driving. Design: Participants drove 55 km (at 90km/h) on a 9-m-wide rural highway in southern Sweden. Daytime driving started at 09:00 or 11:00 (2 groups) and night driving at 01:00 or 03:00 (balanced design). Setting: Instrumented car on a real road in normal traffic. Participants: Eighteen participants drawn from the local driving license register. Interventions: Daytime and nighttime drives. Measurement and Results: The vehicle was an instrumented car with video monitoring of the edge of the road and recording of the lateral position and speed. Electroencephalography and electrooculography were recorded, together with ratings of sleepiness every 5 minutes. Pronounced effects of night driving were seen for subjective sleepiness, electroencephalographic indicators of sleepiness, blink duration, and speed. Also, time on task showed significant effects for subjective sleepiness, blink duration, lane position, and speed. Sleepiness was highest toward the end of the nighttime drive. Night driving caused a leftward shift in lateral position and a reduction of speed. The latter two findings, as well as the overall pattern of sleepiness indicators, provide new insights into the effects of night driving. Conclusion: Night driving is associated with high levels of subjective, electrophysiologic, and behavioral sleepiness. Citation: Sandberg D; Anund A; Fors C; Kecklund G; Karlsson JG; Wahde M; Åkerstedt T. The characteristics of sleepiness during real driving at night—a study of driving performance, physiology and subjective experience. SLEEP 2011;34(10):1317-1325. PMID:21966063

  10. What is the biochemical and physiological rationale for using cold-water immersion in sports recovery? A systematic review.

    PubMed

    Bleakley, Chris M; Davison, Gareth W

    2010-02-01

    Cold-water immersion (CWI) is a popular recovery intervention after exercise. The scientific rationale is not clear, and there are no clear guidelines for its use. The aim of this review was to study the physiological and biochemical effect of short periods of CWI. A computer-based literature search, citation tracking and related articles searches were undertaken. Primary research studies using healthy human participants, immersed in cold water (<15 degrees C), for 5 min durations or less were included. Data were extracted on body temperature, cardiovascular, respiratory and biochemical response. 16 studies were included. Sample size was restricted, and there was a large degree of study heterogeneity. CWI was associated with an increase in heart rate, blood pressure, respiratory minute volume and metabolism. Decreases in end tidal carbon dioxide partial pressure and a decrease in cerebral blood flow were also reported. There was evidence of increases in peripheral catecholamine concentration, oxidative stress and a possible increase in free-radical-species formation. The magnitude of these responses may be attenuated with acclimatisation. CWI induces significant physiological and biochemical changes to the body. Much of this evidence is derived from full body immersions using resting healthy participants. The physiological and biochemical rationale for using short periods of CWI in sports recovery still remains unclear.

  11. Physiology and transcriptomics of water-deficit stress responses in wheat cultivars TAM 111 and TAM 112.

    PubMed

    Reddy, Srirama Krishna; Liu, Shuyu; Rudd, Jackie C; Xue, Qingwu; Payton, Paxton; Finlayson, Scott A; Mahan, James; Akhunova, Alina; Holalu, Srinidhi V; Lu, Nanyan

    2014-09-01

    Hard red winter wheat crops on the U.S. Southern Great Plains often experience moderate to severe drought stress, especially during the grain filling stage, resulting in significant yield losses. Cultivars TAM 111 and TAM 112 are widely cultivated in the region, share parentage and showed superior but distinct adaption mechanisms under water-deficit (WD) conditions. Nevertheless, the physiological and molecular basis of their adaptation remains unknown. A greenhouse study was conducted to understand the differences in the physiological and transcriptomic responses of TAM 111 and TAM 112 to WD stress. Whole-plant data indicated that TAM 112 used more water, produced more biomass and grain yield under WD compared to TAM 111. Leaf-level data at the grain filling stage indicated that TAM 112 had elevated abscisic acid (ABA) content and reduced stomatal conductance and photosynthesis as compared to TAM 111. Sustained WD during the grain filling stage also resulted in greater flag leaf transcriptome changes in TAM 112 than TAM 111. Transcripts associated with photosynthesis, carbohydrate metabolism, phytohormone metabolism, and other dehydration responses were uniquely regulated between cultivars. These results suggested a differential role for ABA in regulating physiological and transcriptomic changes associated with WD stress and potential involvement in the superior adaptation and yield of TAM 112. PMID:25014264

  12. Physiology and transcriptomics of water-deficit stress responses in wheat cultivars TAM 111 and TAM 112.

    PubMed

    Reddy, Srirama Krishna; Liu, Shuyu; Rudd, Jackie C; Xue, Qingwu; Payton, Paxton; Finlayson, Scott A; Mahan, James; Akhunova, Alina; Holalu, Srinidhi V; Lu, Nanyan

    2014-09-01

    Hard red winter wheat crops on the U.S. Southern Great Plains often experience moderate to severe drought stress, especially during the grain filling stage, resulting in significant yield losses. Cultivars TAM 111 and TAM 112 are widely cultivated in the region, share parentage and showed superior but distinct adaption mechanisms under water-deficit (WD) conditions. Nevertheless, the physiological and molecular basis of their adaptation remains unknown. A greenhouse study was conducted to understand the differences in the physiological and transcriptomic responses of TAM 111 and TAM 112 to WD stress. Whole-plant data indicated that TAM 112 used more water, produced more biomass and grain yield under WD compared to TAM 111. Leaf-level data at the grain filling stage indicated that TAM 112 had elevated abscisic acid (ABA) content and reduced stomatal conductance and photosynthesis as compared to TAM 111. Sustained WD during the grain filling stage also resulted in greater flag leaf transcriptome changes in TAM 112 than TAM 111. Transcripts associated with photosynthesis, carbohydrate metabolism, phytohormone metabolism, and other dehydration responses were uniquely regulated between cultivars. These results suggested a differential role for ABA in regulating physiological and transcriptomic changes associated with WD stress and potential involvement in the superior adaptation and yield of TAM 112.

  13. Physiological, Morphological and Behavioural Responses of Self-Feeding Precocial Chicks Copying with Contrasting Levels of Water Salinity during Development

    PubMed Central

    Rocha, Afonso R.; Silva, Rita; Villegas, Auxiliadora; Sánchez-Guzmán, Juan M.; Ramos, Jaime A.; Masero, José A.

    2016-01-01

    Combined physiological and behavioural responses to salt loads during development have rarely been studied in air-breathing vertebrates able to inhabit hypersaline habitats, but they may be of particular importance in understanding, for example, the differences among species in patterns of habitat use or ontogenetic diet switches. Here, we compared the physiological and behavioural responses of self-feeding precocial chicks developed in contrasting levels of water salinity. The model species was the Black-winged Stilt (Himantopus himantopus) a precocial shorebird that breeds in a range of habitats from freshwater to hypersaline wetlands. Specifically, we compared resting metabolic rate (RMR), heat shock proteins (Hsp70), plasma ions, hematocrit, body mass, body size, growth rate and head-shaking behaviour of captive-reared Black-winged Stilt fledglings developed under fresh (0 ‰), saline (20 ‰), and hypersaline (60 ‰) water. Contrary to expectations, none of the physiological and morphological variables measured differed significantly among treatments. Likewise, the RMR of wild and captive-reared fledglings was similar. Surprisingly, the saltgland mass of wild fledglings from freshwater and those from hypersaline habitats was also similar. However, head-shaking, a behavioural response associated to minimize salt intake and to expel the secretions of salt glands, differed according to salinity source: head-shaking rate increased with increasing salinity. The results of this study support the key role of behavioural osmoregulation in avoiding salt stress during development. PMID:27788200

  14. Leaf physiology and biomass allocation of backcross hybrid American chestnut (Castanea dentata) seedlings in response to light and water availability.

    PubMed

    Brown, Caleb E; Mickelbart, Michael V; Jacobs, Douglass F

    2014-12-01

    Partial canopy cover promotes regeneration of many temperate forest trees, but the consequences of shading on seedling drought resistance are unclear. Reintroduction of blight-resistant American chestnut (Castanea dentata (Marsh.) Borkh.) into eastern North American forests will often occur on water-limited sites and under partial canopy cover. We measured leaf pre-dawn water potential (Ψpd), leaf gas exchange, and growth and biomass allocation of backcross hybrid American chestnut seedlings from three orchard sources grown under different light intensities (76, 26 and 8% full photosynthetically active radiation (PAR)) and subjected to well-watered or mid-season water-stressed conditions. Seedlings in the water-stress treatment were returned to well-watered conditions after wilting to examine recovery. Seedlings growing under medium- and high-light conditions wilted at lower leaf Ψpd than low-light seedlings. Recovery of net photosynthesis (Anet) and stomatal conductance (gs) was greater in low and medium light than in high light. Seed source did not affect the response to water stress or light level in most cases. Between 26 and 8% full PAR, light became limiting to the extent that the effects of water stress had no impact on some growth and morphological traits. We conclude that positive and negative aspects of shading on seedling drought tolerance and recovery are not mutually exclusive. Partial shade may help American chestnut tolerate drought during early establishment through effects on physiological conditioning.

  15. Lead-leaching characteristics of submersible residential water pumps

    SciTech Connect

    Maas, R.P.; Patch, S.C.; Pope, J.; Thornton, L.

    1998-01-01

    In June 1991, the US Environmental Protection Agency set an action level of 15 micrograms per liter ({micro}g/L) for lead in drinking water and a maximum contaminant level goal of 0 {micro}g/L at the point of use. Consequently, it is important to understand the cumulative effect of lead exposure from all parts of a residential plumbing distribution system. This paper presents findings of the lead-leaching characteristics of submersible water pumps used in residential wells, which were tested under standard laboratory conditions and under actual residential usage patterns. Laboratory experiments found lead to be leaching in hundreds of {micro}g/L after 10 days of testing; when dilution factors approximating typical residential usage conditions were applied, both the laboratory and the field installation results were in the 3 to 5 {micro}g/L range after 30 days of testing. Exposures after several months were also determined, and overall, leaded-brass well pumps are concluded to represent a marginally significant source of lead exposure to the approximately 40 million Americans served by individual wells.

  16. Fog interception by Sequoia sempervirens (D. Don) crowns decouples physiology from soil water deficit.

    PubMed

    Simonin, Kevin A; Santiago, Louis S; Dawson, Todd E

    2009-07-01

    Although crown wetting events can increase plant water status, leaf wetting is thought to negatively affect plant carbon balance by depressing photosynthesis and growth. We investigated the influence of crown fog interception on the water and carbon relations of juvenile and mature Sequoia sempervirens trees. Field observations of mature trees indicated that fog interception increased leaf water potential above that of leaves sheltered from fog. Furthermore, observed increases in leaf water potential exceeded the maximum water potential predicted if soil water was the only available water source. Because field observations were limited to two mature trees, we conducted a greenhouse experiment to investigate how fog interception influences plant water status and photosynthesis. Pre-dawn and midday branchlet water potential, leaf gas exchange and chlorophyll fluorescence were measured on S. sempervirens saplings exposed to increasing soil water deficit, with and without overnight canopy fog interception. Sapling fog interception increased leaf water potential and photosynthesis above the control and soil water deficit treatments despite similar dark-acclimated leaf chlorophyll fluorescence. The field observations and greenhouse experiment show that fog interception represents an overlooked flux into the soil-plant-atmosphere continuum that temporarily, but significantly, decouples leaf-level water and carbon relations from soil water availability.

  17. Saline water irrigation effects on soil salinity distribution and some physiological responses of field grown Chemlali olive.

    PubMed

    Ben Ahmed, Chedlia; Magdich, Salwa; Ben Rouina, Bechir; Boukhris, Makki; Ben Abdullah, Ferjani

    2012-12-30

    The shortage of water resources of good quality is becoming an issue in arid and semi arid regions. Per consequent, the use of water resources of marginal quality is becoming an important consideration, particularly in arid regions in Tunisia, where large quantities of saline water are used for irrigation. Nevertheless, the use of these waters in irrigated lands requires the control of soil salinity and a comprehensive analysis even beyond the area where water is applied. The aim of this study was to investigate the effects of saline water irrigation on soil salinity distribution and some physiological traits of field-grown adult olive trees (Olea europaea L. cv. Chemlali) under contrasting environmental conditions of the arid region in the south of Tunisia. The plants were subjected, over two growing seasons, to two drip irrigated treatments: fresh water (ECe=1.2 dS m(-1), FW) and saline water (ECe=7.5 dS m(-1), SW). Saline water irrigation (SW) has led to a significant increase in soil salinity. Furthermore, these results showed that soil salinity and soil moisture variations are not only dependent on water salinity level but are also controlled by a multitude of factors particularly the soil texture, the distance from the irrigation source and climatic conditions (rainfall pattern, temperature average, …). On the other hand, salt treatment reduced leaf midday water potential (LMWP), relative water content and photosynthetic activity and increased the leaf proline content, and this increase was season-dependent. Indeed, LMWP in SW plants decreased to -3.71 MPa. Furthermore, the highest level of proline in SW plants was registered during summer period (2.19 μmol/mg Fw). The proline accumulation recorded in stressed plants has allowed them to preserve appropriate leaf water status and photosynthetic activity. More to the point, this olive cultivar seems to be more sensible to soil salinity during the intense growth phase. Such tendencies would help to better

  18. Effects of longterm elevated carbon dioxide concentration, nitrogen and water availability on the physiology of loblolly pine (Pinus taeda) branches

    SciTech Connect

    Murthy, R.; Dougherty, P.M. )

    1994-06-01

    The objective of this study was to determine to what extent elevated CO[sub 2] alters carbon fixation of loblolly pine when water and nutrition are limiting. Three branches per tree were enclosed in polytene chambers and exposed to ambient, 1.5*ambient and 2*ambient levels of CO[sub 2] respectively for a 12 month period. A 2*2 factorial of nutrition and water was employed. Monthly instantaneous measures of maximum photosynthesis (amax), stomatal conductance and other physiological parameters were taken on needles. Branches exposed to 2* ambient CO[sub 2] in the fertilized and irrigated plots showed significantly higher amax values compared to the other treatment level combinations and showed no signs of acclimation. Results suggest that response to elevated CO[sub 2] levels depends greatly on whether nutrition and water are limiting.

  19. Structural and physiological responses of two invasive weeds, Mikania micrantha and Chromolaena odorata, to contrasting light and soil water conditions.

    PubMed

    Zhang, Ling-Ling; Wen, Da-Zhi

    2009-01-01

    To better understand the requirement of light and soil water conditions in the invasion sites of two invasive weeds, Mikania micrantha and Chromolaena odorata, we investigated their structural and physiological traits in response to nine combined treatments of light [full, medium and low irradiance (LI)] and soil water (full, medium and low field water content) conditions in three glasshouses. Under the same light conditions, most variables for both species did not vary significantly among different water treatments. Irrespective of water treatment, both species showed significant decreases in maximum light saturated photosynthetic rate (P (max)), photosynthetic nitrogen-use efficiency, and relative growth rate under LI relative to full irradiance; specific leaf area, however, increased significantly from full to LI though leaf area decreased significantly, indicating that limited light availability under extreme shade was the critical factor restricting the growth of both species. Our results also indicated that M. micrantha performed best under a high light and full soil water combination, while C. odorata was more efficient in growth under a high light and medium soil water combination.

  20. Characteristics analysis for different water heads on the efficiency hill chart of Francis turbine

    NASA Astrophysics Data System (ADS)

    Wang, Z. N.; Guo, P. C.; Luo, X. Q.; Wang, Y. L.; Sun, S. H.

    2016-05-01

    Based on the test results of Francis turbine, the causes and inevitability of various hydraulic phenomena in the model combined characteristic curve for typical water heads were analyzed in this paper. the difference of the model combined characteristic curve from the low water head to the high water head is compared, and the characteristics and commonness of the model combined characteristic curve about different water head are summarized. Further, hydraulic performance and geometric features of Francis turbine are revealed by particularly analyzing model combined characteristic curves, and to provide powerful theoretical basis and definite modification direction for the hydraulic design of hydraulic turbine.

  1. Water source as a housing characteristic: Hedonic property valuation and willingness to pay for water

    NASA Astrophysics Data System (ADS)

    North, J. H.; Griffin, C. C.

    1993-07-01

    Using data from a large representative sample of rural households in one region of the Philippines, we estimate the determinants of the rental value of dwellings using the bid-rent approach to the hedonic price model. Our particular interest is in the relative valuation these households place on owning a private source of water and distance to a public or communal source. We find that low-, middle-, and high-income households value an in-house piped water source highly relative to other characteristics of their homes. Middle- and high-income households value a deep well or piped water in the yard, although at a substantially lower level than piped water in the house. It is somewhat surprising to find that, except in the case of high-income families, households appear to gain little or no utility from having a communal source of water, such as a river, lake, or public tap, closer to their homes. As a consequence, public water policies that emphasize improving the quality and proximity of communal sources would be inappropriate for the region represented by this sample.

  2. Water films and scaling of soil characteristic curves at low water contents

    NASA Astrophysics Data System (ADS)

    Tuller, Markus; Or, Dani

    2005-09-01

    Individual contributions of capillarity and adsorptive surface forces to the matric potential are seldom differentiated in determination of soil water characteristic (SWC) curves. Typically, capillary forces dominate at the wet end, whereas adsorptive surface forces dominate at the dry end of a SWC where water is held as thin liquid films. The amount of adsorbed soil water is intimately linked to soil specific surface area (SA) and plays an important role in various biological and transport processes in arid environments. Dominated by van der Waals adsorptive forces, surface-water interactions give rise to a nearly universal scaling relationship for SWC curves at low water contents. We demonstrate that scaling measured water content at the dry end by soil specific surface area yields remarkable similarity across a range of soil textures and is in good agreement with theoretical predictions based on van der Waals interactions. These scaling relationships are important for accurate description of SWC curves in dry soils and may provide rapid and reliable estimates of soil specific surface area from SWC measurements for matric potentials below -10 MPa conveniently measured with the chilled-mirror dew point technique. Surface area estimates acquired by fitting the scaling relationship to measured SWC data were in good agreement with SA data measured by standard methods. Preliminary results suggest that the proposed method could provide reliable SA estimates for natural soils with hydratable surface areas smaller than 200 m2/g.

  3. Water films and scaling of soil characteristic curves at low water contents

    NASA Astrophysics Data System (ADS)

    Tuller, Markus; Or, Dani

    2005-09-01

    Individual contributions of capillarity and adsorptive surface forces to the matric potential are seldom differentiated in determination of soil water characteristic (SWC) curves. Typically, capillary forces dominate at the wet end, whereas adsorptive surface forces dominate at the dry end of a SWC where water is held as thin liquid films. The amount of adsorbed soil water is intimately linked to soil specific surface area (SA) and plays an important role in various biological and transport processes in arid environments. Dominated by van der Waals adsorptive forces, surface-water interactions give rise to a nearly universal scaling relationship for SWC curves at low water contents. We demonstrate that scaling measured water content at the dry end by soil specific surface area yields remarkable similarity across a range of soil textures and is in good agreement with theoretical predictions based on van der Waals interactions. These scaling relationships are important for accurate description of SWC curves in dry soils and may provide rapid and reliable estimates of soil specific surface area from SWC measurements for matric potentials below ‒10 MPa conveniently measured with the chilled-mirror dew point technique. Surface area estimates acquired by fitting the scaling relationship to measured SWC data were in good agreement with SA data measured by standard methods. Preliminary results suggest that the proposed method could provide reliable SA estimates for natural soils with hydratable surface areas smaller than 200 m2/g.

  4. Distribution of characteristics of LWR [light water reactor] spent fuel

    SciTech Connect

    Reich, W.J.; Notz, K.J.; Moore, R.S.

    1991-01-01

    The purpose of this report is to develop a collective description of the entire spent fuel inventory in terms of various fuel properties relevant to Approved Testing Materials (ATMs) using information available from the Characteristics Data Base (CBD), which is sponsored by the US Department of Energy`s (DOE`s) Office of Civilian Radioactive Waste Management. A number of light-water reactor (LWR) characteristics were analyzed including assembly class representation, fuel burnup, enrichment, fuel fabrication data, defective fuel quantities, and, at PNL`s specific request, linear heat generation rate (LHGR) and the utilization of burnable poisons. A quantitative relationships was developed between burnup and enrichment for BWRs and PWRs. The relationship shows that the existing BWR ATM is near the center of the burnup-enrichment distribution, while the four PWR ATMs bracket the center of the burnup range but are on the low side of the enrichment range. Fuel fabrication data are based on vendor specifications for new fuel. Defective fuel distributions were analyzed in terms of assembly class and vendor design. LHGR values were calculated from utility data on burnup and effective full-power days; these calculations incorporate some unavoidable assumptions which may compromise the value of the results. Only a limited amount of data are available on burnable poisons at this time. Based on this distribution study, suggestions for additional ATMs are made. These are based on the class and design concepts and include BWR/2,3 barrier fuel, and the WE 17 {times} 17 class with integral burnable poison. Both should be at relatively high burnups. 16 refs., 5 figs., 15 tabs.

  5. [Effects of different application amount of N, P, K fertilizers on physiological characteristics, yield and kernel quality of peanut].

    PubMed

    Zhou, Lu-ying; Li, Xiang-dong; Tang, Xiao; Lin, Ying-jie; Li, Zong-feng

    2007-11-01

    The field experiment was executed with peanut cv. Fenghua No. 1 from 2004 to 2005 in the experimental station of Shandong Agricultural University to study the effects of N, P, K fertilizers application amount on physiological characteristics, yield and kernel quality of peanut. The results showed that, compared with no fertilization, application N, P, K fertilizers increased the content of chlorophyll and soluble protein, enhanced photosynthetic rate and the activities of superoxide dismutase (SOD), peroxidase (POD) and catlase (CAT), and reduced malondialdeyde (MDA) accumulation amount in peanut leaves. The effects of applying N 300-450 kg x hm(-2), P5O2, 150-225 kg x hm(-2) and K2O 300-450 kg x hm(-2) treatments were the most significant. The improvement effect of N fertilizer on photosynthesis properties was mainly at early stage, and that of P was at middle-later stage, K was at whole stage. Applying N, P, K fertilizers increased the pod yield of peanut remarkably, and with the increasing of N application amount the pod yield enhanced, the pod yields were highest when P and K application were at middle amount rates (P5O2, 150 kg x hm(-2) K2O 300 kg x hm(-2)). The increasing effect on pod yield of K fertilizer was greater than that of N and P fertilizers. Applying a small amount of P and K fertilizers (P2O5 75 kg x hm(-2), K2O 150 kg x hm(-2)) could significantly increase the contents of fat and protein in peanut kernel, applying a small amount of N fertilizer (N 150 kg x hm(-2)) could significantly increase the content of protein in peanut kernel, but applying a large amount of N fertilizer (N 450 kg x hm(-2)) could significantly increase the content of fat in peanut kernel. Applying P fertilizer obviously increased fat and protein content, applying N fertilizer mainly enhanced protein content, and applying K fertilizer mainly raised the content of soluble sugar. In addition, the application of N, P and K fertilizers also increased the contents of lysine and

  6. Water-Landing Characteristics of a Reentry Capsule

    NASA Technical Reports Server (NTRS)

    McGehee, John R.; Hathaway, Melvin E.; Vaughan, Victor L., Jr.

    1959-01-01

    Experimental and theoretical investigations have been made to determine the water-landing characteristics of a conical-shaped reentry capsule having a segment of a sphere as the bottom. For the experimental portion of the investigation, a 1/12-scale model capsule and a full-scale capsule were tested for nominal flight paths of 65 deg and 90 deg (vertical), a range of contact attitudes from -30 deg to 30 deg, and a full-scale vertical velocity of 30 feet per second at contact. Accelerations were measured by accelerometers installed at the centers of gravity of the model and full-scale capsules. For the model test the accelerations were measured along the X-axis (roll) and Z-axis (yaw) and for the full-scale test they were measured along the X-axis (roll), Y-axis (pitch), and Z-axis (yaw). Motions and displacements of the capsules that occurred after contact were determined from high-speed motion pictures. The theoretical investigation was conducted to determine the accelerations that might occur along the X-axis when the capsule contacted the water from a 90 deg flight path at a 0 deg attitude. Assuming a rigid body, computations were made from equations obtained by utilizing the principle of the conservation of momentum. The agreement among data obtained from the model test, the full-scale test, and the theory was very good. The accelerations along the X-axis, for a vertical flight path and 0 deg attitude, were in the order of 40g. For a 65 deg flight path and 0 deg attitude, the accelerations along the X-axis were in the order of 50g. Changes in contact attitude, in either the positive or negative direction from 0 deg attitude, considerably reduced the magnitude of the accelerations measured along the X-axis. Accelerations measured along the Y- and Z-axes were relatively small at all test conditions.

  7. An investigation of dispersion characteristics in shallow coastal waters

    NASA Astrophysics Data System (ADS)

    Yu, Yingying; Zhang, Hong; Spencer, David; Dunn, Ryan J. K.; Lemckert, Charles

    2016-10-01

    Hydrodynamic dispersion has a significant impact on the mass transport of sediments and contaminants within coastal waters. In this study apparent horizontal dispersion in a tidally-dominated shallow estuary was investigated using field observations and a numerical model. A cluster of four Lagrangian drifters was released in two shallow regions inside Moreton Bay, Australia: between two small islands and in an open water area. During a 16-h tracking period, the drifters generally showed similar behaviour, initially moving with the dominant current and remaining together before spreading apart at the change of tide. Two dispersion regimes were identified, a slow dispersion during the earlier stage and a rapid dispersion during the latter stage of deployment. Such change in regime typically occurred during the succeeding ebb or flow tides, which may be attributable to residual eddies breaking down during reversal of tidal direction. In addition, a power function of the squared separation distance over the apparent dispersion coefficient produced an R2 exceeding 0.7, indicating a significant relationship between them. By applying a three-dimensional hydrodynamic model, the trajectories of artificial particles spreading in the bay were simulated, which allowed the calculation of dispersion coefficients throughout the entire bay. The study results demonstrate that the tidal effects on dispersion were dependent on the effect of tidal excursion and residual current. The tide was found to be the most dominant driver of dispersion in the bay when unobstructed by land; however, bathymetric and shoreline characteristics were also significant localised drivers of dispersion between the two islands as a result of island wake.

  8. Physiological Traits Associated with Wheat Yield Potential and Performance under Water-Stress in a Mediterranean Environment.

    PubMed

    Del Pozo, Alejandro; Yáñez, Alejandra; Matus, Iván A; Tapia, Gerardo; Castillo, Dalma; Sanchez-Jardón, Laura; Araus, José L

    2016-01-01

    Different physiological traits have been proposed as key traits associated with yield potential as well as performance under water stress. The aim of this paper is to examine the genotypic variability of leaf chlorophyll, stem water-soluble carbohydrate content and carbon isotope discrimination (Δ(13)C), and their relationship with grain yield (GY) and other agronomical traits, under contrasting water conditions in a Mediterranean environment. The study was performed on a large collection of 384 wheat genotypes grown under water stress (WS, rainfed), mild water stress (MWS, deficit irrigation), and full irrigation (FI). The average GY of two growing seasons was 2.4, 4.8, and 8.9 Mg ha(-1) under WS, MWS, and FI, respectively. Chlorophyll content at anthesis was positively correlated with GY (except under FI in 2011) and the agronomical components kernels per spike (KS) and thousand kernel weight (TKW). The WSC content at anthesis (WSCCa) was negatively correlated with spikes per square meter (SM2), but positively correlated with KS and TKW under WS and FI conditions. As a consequence, the relationships between WSCCa with GY were low or not significant. Therefore, selecting for high stem WSC would not necessary lead to genotypes of GY potential. The relationship between Δ(13)C and GY was positive under FI and MWS but negative under severe WS (in 2011), indicating higher water use under yield potential and MWS conditions.

  9. Physiological Traits Associated with Wheat Yield Potential and Performance under Water-Stress in a Mediterranean Environment

    PubMed Central

    del Pozo, Alejandro; Yáñez, Alejandra; Matus, Iván A.; Tapia, Gerardo; Castillo, Dalma; Sanchez-Jardón, Laura; Araus, José L.

    2016-01-01

    Different physiological traits have been proposed as key traits associated with yield potential as well as performance under water stress. The aim of this paper is to examine the genotypic variability of leaf chlorophyll, stem water-soluble carbohydrate content and carbon isotope discrimination (Δ13C), and their relationship with grain yield (GY) and other agronomical traits, under contrasting water conditions in a Mediterranean environment. The study was performed on a large collection of 384 wheat genotypes grown under water stress (WS, rainfed), mild water stress (MWS, deficit irrigation), and full irrigation (FI). The average GY of two growing seasons was 2.4, 4.8, and 8.9 Mg ha−1 under WS, MWS, and FI, respectively. Chlorophyll content at anthesis was positively correlated with GY (except under FI in 2011) and the agronomical components kernels per spike (KS) and thousand kernel weight (TKW). The WSC content at anthesis (WSCCa) was negatively correlated with spikes per square meter (SM2), but positively correlated with KS and TKW under WS and FI conditions. As a consequence, the relationships between WSCCa with GY were low or not significant. Therefore, selecting for high stem WSC would not necessary lead to genotypes of GY potential. The relationship between Δ13C and GY was positive under FI and MWS but negative under severe WS (in 2011), indicating higher water use under yield potential and MWS conditions. PMID:27458470

  10. Physiological Traits Associated with Wheat Yield Potential and Performance under Water-Stress in a Mediterranean Environment.

    PubMed

    Del Pozo, Alejandro; Yáñez, Alejandra; Matus, Iván A; Tapia, Gerardo; Castillo, Dalma; Sanchez-Jardón, Laura; Araus, José L

    2016-01-01

    Different physiological traits have been proposed as key traits associated with yield potential as well as performance under water stress. The aim of this paper is to examine the genotypic variability of leaf chlorophyll, stem water-soluble carbohydrate content and carbon isotope discrimination (Δ(13)C), and their relationship with grain yield (GY) and other agronomical traits, under contrasting water conditions in a Mediterranean environment. The study was performed on a large collection of 384 wheat genotypes grown under water stress (WS, rainfed), mild water stress (MWS, deficit irrigation), and full irrigation (FI). The average GY of two growing seasons was 2.4, 4.8, and 8.9 Mg ha(-1) under WS, MWS, and FI, respectively. Chlorophyll content at anthesis was positively correlated with GY (except under FI in 2011) and the agronomical components kernels per spike (KS) and thousand kernel weight (TKW). The WSC content at anthesis (WSCCa) was negatively correlated with spikes per square meter (SM2), but positively correlated with KS and TKW under WS and FI conditions. As a consequence, the relationships between WSCCa with GY were low or not significant. Therefore, selecting for high stem WSC would not necessary lead to genotypes of GY potential. The relationship between Δ(13)C and GY was positive under FI and MWS but negative under severe WS (in 2011), indicating higher water use under yield potential and MWS conditions. PMID:27458470

  11. Water supplementation affects the behavioral and physiological ecology of Gila monsters (Heloderma suspectum) in the Sonoran Desert.

    PubMed

    Davis, Jon R; DeNardo, Dale F

    2009-01-01

    In desert species, seasonal peaks in animal activity often correspond with times of higher rainfall. However, the underlying reason for such seasonality can be hard to discern because the rainy season is often associated with shifts in temperature as well as water and food availability. We used a combination of the natural climate pattern of the Sonoran Desert and periodic water supplementation to determine the extent to which water intake influenced both the behavioral ecology and the physiological ecology of a long-lived desert lizard, the Gila monster (Heloderma suspectum) (Cope 1869). Water-supplemented lizards had lower plasma osmolality (i.e., were more hydrated) and maintained urinary bladder water reserves better during seasonal drought than did control lizards. During seasonal drought, water-supplemented lizards were surface active a significantly greater proportion of time than were controls. This increased surface activity can lead to greater food acquisition for supplemental Gila monsters because tail volume (an index of caudal lipid stores) was significantly greater in supplemented lizards compared with controls in one of the two study years.

  12. Influence of different irrigation levels on the root water uptake and the physiology of root-chicory

    NASA Astrophysics Data System (ADS)

    Vandoorne, B.; Dekoninck, N.; Lutts, S.; Capelle, B.; Javaux, M.

    2009-04-01

    In the context of global warming and given recent heat waves observed in Western Europe, the relationship between the soil water status and the plant health has recently received more attention, especially for cash crops like chicory. In this study we particularly investigated the impact of soil water status on the chicory root water uptake and density and made a link with physiological and yield parameters. During five months, we imposed different irrigation levels to 10 plants of chicory (Cichorium intybus var. sativum) growing in greenhouses. Each seed, coming from an autogamous selection in this allogamous species, was sown in a column of 1.42m height and 0.4m diameter filled with yellow sand and irrigated from the bottom with Hoagland solution. On those 10 columns, we measured the distribution of soil moisture with TDR (8 columns) and ERT (2 columns) probes. Lateral windows also allowed us to follow the root growth. The column weights were also monitored in order to quantify the plant transpiration. During the experiment, several physiological indices were also followed like the gas exchange (CO2 and transpiration), the chlorophyll fluorescence, the stomatal conductance, the plastochron, and the Leaf Area Index (LAI). At the end of the experiment, the complete root length density and the water content profiles were measured. We had also a look to the osmotic potential, the pigments content and the isotopic discrimination of carbon in the leaves, which gives information about the level of stress. At a biochemical point of view, we measured the content in enzymes involves in inulin metabolism and sugars synthesis. We observed that the plants suffering from a slight water stress developed better. A simple1-D model was built which describes the root growth in function of the irrigation level and of the soil and atmospheric boundary conditions.

  13. A Comparison of Water Balance Components of a Spruce and a Beech Canopy Based on Parallel Micrometeorological and Plant Physiological Measurements

    NASA Astrophysics Data System (ADS)

    Spank, Uwe; Bernhofer, Christian; Clausnitzer, Falko; Köstner, Babara; Schwärzel, Kai; Feger, Karl-Heinz

    2010-05-01

    -third of Pn at the beech site. Ps is negligible in the spruce canopy. The statistical analyses of Pc showed a Pt of 12 % at the spruce site and 14 % at the beech site, which correspond to expectations, derived from measured sky view coefficients. In this context the important regulating role of Pt for silvicultural, ecological and hydrological issues becomes clear. The analyses of ET, T and I as well as the integration of ? to close of water balance were complex due to different scales of measurements. Which are different scales of EC measurements (used for ET) and SF measurements (used for T) as well as spatial heterogeneity of ?. To overcome the scale problem in components of ET somewhat an inverse solution of Penman's approach was used to separate T and I in the EC data. Here we found: differences in T between both canopies are caused predominately by different Wa in both canopies. However, influences due to differences of plant physiological characteristics between beeches and spruces were found to be less important. The potential water supply depends on two parameters: characteristics of soils and range of rooting zone. Therefore, soil characteristics determine water balance significantly under all climate conditions. However, the range of the rooting zone and the specifics of roots are only significant in droughts and dry periods, when water supply is restricted. Differences in interception between both canopies were found to be negligible during the growing season.

  14. [Characteristics of the physiological functions in the operators of foundry transfer lines in the course of the work day and week].

    PubMed

    Solov'eva, L P; Dobzhinskiĭ, V G; Peredera, N N; Romanov, D A

    1989-01-01

    The correlation analysis covered the state of the cardiovascular, hemodynamic, thermoregulatory, vegetative nervous systems, the characteristics of strength, endurance, attention, readiness to action among operators of transfer foundry lines during working days and weeks. It was shown that the main physiologic changes occurred at the initial stage, i. e., on the first day before the dinner break. To the end of the working week correlational links were established among temperature, arterial pressure, characteristics of strength, endurance, the time necessary for response and attention, thus higher intensity of the thermoregulatory system functioning being evidenced.

  15. Physiological and behavioral responses to different watering intervals in lactating camels (Camelus dromedarius).

    PubMed

    Bekele, Tafesse; Olsson, Kerstin; Olsson, Ulf; Dahlborn, Kristina

    2013-09-15

    During drought periods camels are watered at long intervals, but effects on body fluid homeostasis of lactating camels are not known. It was hypothesized that camels store water after drinking and minimize water losses by diurnal variation in body temperature, changes in behavior, and release of vasopressin. The aim was to find a sustainable watering interval for lactating camels. Seven lactating camels were studied in a cross-over trial in which they were watered once daily (W1), every fourth day (W4), every eighth day (W8), or after 16 days (W16) with a 5-day interval between treatments. When offered water every fourth or eighth days, the camels drank sufficient amounts to cover their needs for subsequent days, but after 16 days of dehydration they did not drink enough to compensate the body weight loss. Rectal temperature fell at night and the camels searched shade during daytime minimizing evaporative fluid losses. Plasma osmolality and sodium concentration were elevated after 4 days of water deprivation and plasma protein and vasopressin concentrations after 8 days. Milk production decreased during the last week of W16. Plasma aldosterone concentration was elevated upon rehydration after W16, indicating sodium deficiency. In conclusion, lactating camels stored water after drinking and reduced water losses by staying in shade, keeping body temperature low, and releasing plasma vasopressin. However, serious dehydration was observed during W8, and after 16 days of water deprivation recovery took a long time. A watering interval between 4 and 7 days seems advisable under similar environmental conditions.

  16. A putative low-molecular-mass penicillin-binding protein (PBP) of Mycobacterium smegmatis exhibits prominent physiological characteristics of DD-carboxypeptidase and beta-lactamase.

    PubMed

    Bansal, Ankita; Kar, Debasish; Murugan, Rajagopal A; Mallick, Sathi; Dutta, Mouparna; Pandey, Satya Deo; Chowdhury, Chiranjit; Ghosh, Anindya S

    2015-05-01

    DD-carboxypeptidases (DD-CPases) are low-molecular-mass (LMM) penicillin-binding proteins (PBPs) that are mainly involved in peptidoglycan remodelling, but little is known about the dd-CPases of mycobacteria. In this study, a putative DD-CPase of Mycobacterium smegmatis, MSMEG_2433 is characterized. The gene for the membrane-bound form of MSMEG_2433 was cloned and expressed in Escherichia coli in its active form, as revealed by its ability to bind to the Bocillin-FL (fluorescent penicillin). Interestingly, in vivo expression of MSMEG_2433 could restore the cell shape oddities of the septuple PBP mutant of E. coli, which was a prominent physiological characteristic of DD-CPases. Moreover, expression of MSMEG_2433 in trans elevated beta-lactam resistance in PBP deletion mutants (ΔdacAdacC) of E. coli, strengthening its physiology as a dd-CPase. To confirm the biochemical reason behind such physiological behaviours, a soluble form of MSMEG_2433 (sMSMEG_2433) was created, expressed and purified. In agreement with the observed physiological phenomena, sMSMEG_2433 exhibited DD-CPase activity against artificial and peptidoglycan-mimetic DD-CPase substrates. To our surprise, enzymic analyses of MSMEG_2433 revealed efficient deacylation for beta-lactam substrates at physiological pH, which is a unique characteristic of beta-lactamases. In addition to the MSMEG_2433 active site that favours dd-CPase activity, in silico analyses also predicted the presence of an omega-loop-like region in MSMEG_2433, which is an important determinant of its beta-lactamase activity. Based on the in vitro, in vivo and in silico studies, we conclude that MSMEG_2433 is a dual enzyme, possessing both DD-CPase and beta-lactamase activities.

  17. Does plasticity in plant physiological traits explain the rapid increase in water use efficiency? An ecohydrological modeling approach

    NASA Astrophysics Data System (ADS)

    Mastrotheodoros, Theodoros; Fatichi, Simone; Pappas, Christoforos; Molnar, Peter; Burlando, Paolo

    2016-04-01

    The rise of atmospheric CO2 concentration is expected to stimulate plant productivity by enhancing photosynthesis and reducing stomatal conductance and thus increasing plant water use efficiency (WUE) worldwide. An analysis of eddy covariance flux tower data from 21 forested ecosystems across the north hemisphere detected an unexpectedly large increase in WUE (Keenan et al, 2013), which was six times larger than the increase found by most previous studies based on controlled experiments (e.g., FACE), leaf-scale analyses, and numerical modelling. This increase could be solely attributed to the increase in atmospheric CO2 since other confounding factors were ruled out. Here, we investigate the potential contribution of plant plasticity, reflected in the temporal adjustment of major plant physiological traits, on changes in WUE using the ecohydrological model Tethys and Chloris (T&C). We hypothesize that the increase in WUE can be attributed to small variations in plant physiological traits, undetectable through observations, eventually triggered by the atmospheric CO2 increase. Data from the 21 sites in the above mentioned study are used to force the model. Simulation results with and without plasticity in the physiological traits (i.e., model parameters in our numerical experiments) are compared with the observed trends in WUE. We test several plant adaptation strategies in being effective in explaining the observed increase in WUE using a multifactorial numerical experiment in which we perturb in a systematic way selected plant parameters. Keenan, T. F., Hollinger, D. Y., Bohrer, G., Dragoni, D., Munger, J. W., Schmid, H. P., and Richardson, A. D. (2013). Increase in forest water-use efficiency as atmospheric carbon dioxide concentrations rise. Nature, 499(7458), 324-7.

  18. Antarctic killer whales make rapid, round-trip movements to subtropical waters: evidence for physiological maintenance migrations?

    PubMed

    Durban, J W; Pitman, R L

    2012-04-23

    Killer whales (Orcinus orca) are important predators in high latitudes, where their ecological impact is mediated through their movements. We used satellite telemetry to provide the first evidence of migration for killer whales, characterized by fast (more than 12 km h(-1), 6.5 knots) and direct movements away from Antarctic waters by six of 12 type B killer whales tagged when foraging near the Antarctic Peninsula, including all tags transmitting for more than three weeks. Tags on five of these whales revealed consistent movements to subtropical waters (30-37° S) off Uruguay and Brazil, in surface water temperatures ranging from -1.9°C to 24.2°C; one 109 day track documented a non-stop round trip of almost 9400 km (5075 nmi) in just 42 days. Although whales travelled slower in the warmest waters, there was no obvious interruption in swim speed or direction to indicate calving or prolonged feeding. Furthermore, these movements were aseasonal, initiating over 80 days between February and April; one whale returned to within 40 km of the tagging site at the onset of the austral winter in June. We suggest that these movements may represent periodic maintenance migrations, with warmer waters allowing skin regeneration without the high cost of heat loss: a physiological constraint that may also affect other whales.

  19. Antarctic killer whales make rapid, round-trip movements to subtropical waters: evidence for physiological maintenance migrations?

    PubMed

    Durban, J W; Pitman, R L

    2012-04-23

    Killer whales (Orcinus orca) are important predators in high latitudes, where their ecological impact is mediated through their movements. We used satellite telemetry to provide the first evidence of migration for killer whales, characterized by fast (more than 12 km h(-1), 6.5 knots) and direct movements away from Antarctic waters by six of 12 type B killer whales tagged when foraging near the Antarctic Peninsula, including all tags transmitting for more than three weeks. Tags on five of these whales revealed consistent movements to subtropical waters (30-37° S) off Uruguay and Brazil, in surface water temperatures ranging from -1.9°C to 24.2°C; one 109 day track documented a non-stop round trip of almost 9400 km (5075 nmi) in just 42 days. Although whales travelled slower in the warmest waters, there was no obvious interruption in swim speed or direction to indicate calving or prolonged feeding. Furthermore, these movements were aseasonal, initiating over 80 days between February and April; one whale returned to within 40 km of the tagging site at the onset of the austral winter in June. We suggest that these movements may represent periodic maintenance migrations, with warmer waters allowing skin regeneration without the high cost of heat loss: a physiological constraint that may also affect other whales. PMID:22031725

  20. Physiological, Ultrastructural and Proteomic Responses in the Leaf of Maize Seedlings to Polyethylene Glycol-Stimulated Severe Water Deficiency

    PubMed Central

    Shao, Ruixin; Xin, Longfei; Mao, Jun; Li, Leilei; Kang, Guozhang; Yang, Qinghua

    2015-01-01

    After maize seedlings grown in full-strength Hoagland solution for 20 days were exposed to 20% polyethylene glycol (PEG)-stimulated water deficiency for two days, plant height, shoot fresh and dry weights, and pigment contents significantly decreased, whereas malondialdehyde (MDA) content greatly increased. Using transmission electron microscopy, we observed that chloroplasts of mesophyll cells in PEG-treated maize seedlings were swollen, with a disintegrating envelope and disrupted grana thylakoid lamellae. Using two-dimensional gel electrophoresis (2-DE) method, we were able to identify 22 protein spots with significantly altered abundance in the leaves of treated seedlings in response to water deficiency, 16 of which were successfully identified. These protein species were functionally classified into signal transduction, stress defense, carbohydrate metabolism, protein metabolism, and unknown categories. The change in the abundance of the identified protein species may be closely related to the phenotypic and physiological changes due to PEG-stimulated water deficiency. Most of the identified protein species were putatively located in chloroplasts, indicating that chloroplasts may be prone to damage by PEG stimulated-water deficiency in maize seedlings. Our results help clarify the molecular mechanisms of the responses of higher plants to severe water deficiency. PMID:26370980

  1. Physiological, Ultrastructural and Proteomic Responses in the Leaf of Maize Seedlings to Polyethylene Glycol-Stimulated Severe Water Deficiency.

    PubMed

    Shao, Ruixin; Xin, Longfei; Mao, Jun; Li, Leilei; Kang, Guozhang; Yang, Qinghua

    2015-01-01

    After maize seedlings grown in full-strength Hoagland solution for 20 days were exposed to 20% polyethylene glycol (PEG)-stimulated water deficiency for two days, plant height, shoot fresh and dry weights, and pigment contents significantly decreased, whereas malondialdehyde (MDA) content greatly increased. Using transmission electron microscopy, we observed that chloroplasts of mesophyll cells in PEG-treated maize seedlings were swollen, with a disintegrating envelope and disrupted grana thylakoid lamellae. Using two-dimensional gel electrophoresis (2-DE) method, we were able to identify 22 protein spots with significantly altered abundance in the leaves of treated seedlings in response to water deficiency, 16 of which were successfully identified. These protein species were functionally classified into signal transduction, stress defense, carbohydrate metabolism, protein metabolism, and unknown categories. The change in the abundance of the identified protein species may be closely related to the phenotypic and physiological changes due to PEG-stimulated water deficiency. Most of the identified protein species were putatively located in chloroplasts, indicating that chloroplasts may be prone to damage by PEG stimulated-water deficiency in maize seedlings. Our results help clarify the molecular mechanisms of the responses of higher plants to severe water deficiency. PMID:26370980

  2. The effect of air permeability and water vapor permeability of cleanroom clothing on physiological responses and wear comfort.

    PubMed

    Chen, Te-Hung; Chen, Wan-Ping; Wang, Mao-Jiun J

    2014-01-01

    The function of cleanroom clothing is to protect the product from contamination by people, and to dissipate electrostatic discharge. People in the cleanroom work environment often complain about the discomforts associated with the wearing of cleanroom clothing. The purpose of this study is to investigate the effect of air permeability and water vapor permeability of cleanroom clothing on the subject's physiological and subjective responses. Five male and five female subjects participated in this study. The experimental goal was to simulate the operator's regular tasks in a semiconductor manufacturing cleanroom. Each subject completed three treatment combinations with three different cleanroom clothing types. A three-factor experiment was designed (significance level p = 0.05). The independent variables included gender, cleanroom clothing, and duration. The dependent measures included heart rate, core temperature, skin temperature, micro-climate relative humidity, micro-climate temperature, and subjective responses. A total of 40 min was involved for each treatment condition. The results indicate that skin temperature, micro-climate temperature and micro-climate relative humidity were lower while wearing cleanroom clothing with high air permeability and high water vapor permeability. The significant gender difference was found in skin temperature. As the task time increased, the micro-climate temperature also increased but the micro-climate relative humidity decreased at first and then increased. In addition, the physiological responses showed significant positive correlations with the subjective perception of clothing comfort. The findings of this study may provide useful information for cleanroom clothing design and selection.

  3. Sensitivity of terrestrial water and energy budgets to CO2-physiological forcing: an investigation using an offline land model

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, Ranjith; Bala, Govindsamy; Jayaraman, Mathangi; Cao, Long; Nemani, Ramakrishna; Ravindranath, N. H.

    2011-10-01

    Increasing concentrations of atmospheric carbon dioxide (CO2) influence climate by suppressing canopy transpiration in addition to its well-known greenhouse gas effect. The decrease in plant transpiration is due to changes in plant physiology (reduced opening of plant stomata). Here, we quantify such changes in water flux for various levels of CO2 concentrations using the National Center for Atmospheric Research's (NCAR) Community Land Model. We find that photosynthesis saturates after 800 ppmv (parts per million, by volume) in this model. However, unlike photosynthesis, canopy transpiration continues to decline at about 5.1% per 100 ppmv increase in CO2 levels. We also find that the associated reduction in latent heat flux is primarily compensated by increased sensible heat flux. The continued decline in canopy transpiration and subsequent increase in sensible heat flux at elevated CO2 levels implies that incremental warming associated with the physiological effect of CO2 will not abate at higher CO2 concentrations, indicating important consequences for the global water and carbon cycles from anthropogenic CO2 emissions.

  4. Brackish Eutrophic Water Treatment by Iris pseudacorus L.-Planted Microcosms: Physiological Responses of Iris pseudacorus L. to Salinity.

    PubMed

    Zhao, Huilin; Wang, Fen; Ji, Min

    2015-01-01

    Iris pseudacorus L. has been widely used in aquatic ecosystem to remove nutrient and has achieved positive effects. However, little is known regarding the nutrient-removal performance and physiological responses of I. pseudacorus for brackish eutrophic water treatment due to high nutrients combined with certain salinity levels. In this study, I. pseudacorus-planted microcosms were established to evaluate the capacity of I. pseudacorus to remove excessive nutrients from fresh (salinity 0.05%) and brackish (salinity 0.5%) eutrophic waters. The degradation of total nitrogen and ammonia nitrogen were not affected by 0.5% salinity; 0.5% salinity promoted the degradation of nitrate nitrogen while severely inhibited the degradation of total phosphorus. Additionally, 0.5% salinity was found to induce stress responses quantified by measuring six physiological indexes. Compared to 0.05% salinity, 0.5% salinity resulted in significant decreases in the chlorophyll a, b and total chlorophyll contents of I. pseudacorus which closely related to photosynthesis (p < 0.05). Furthermore, the higher proline, malondialdehyde contents and antioxidant enzyme activities were detected in I. pseudacorus exposed to 0.5% salinity, which provided protection against reactive oxygen species. The results highlight that the cellular stress assays are efficient for monitoring the health of I. pseudacorus in salinity shock-associated constructed wetlands. PMID:25529785

  5. Physiological acclimation of a desert antelope, Arabian oryx (Oryx leucoryx), to long-term food and water restriction.

    PubMed

    Ostrowski, Stéphane; Williams, Joseph B; Mésochina, Pascal; Sauerwein, Helga

    2006-03-01

    Desert mammals often experience scarcity of drinking water and food for prolonged periods. In this study, the first long-term acclimation experiment in a non-domesticated desert-adapted ungulate, we investigated the mechanisms used by the Arabian oryx Oryx leucoryx, to adjust its physiology to progressive food and water restriction over 5 months, an experimental regimen and time course chosen to mimic what it typically experiences between spring and late summer in the desert. At the end of the acclimation period, oryx consumed less than one and half of food and water of animals in the control group and lost 8.2+/-2.6% of their initial body mass. Experimental animals reduced their mass-specific resting metabolic rate (RMR) and total evaporative water loss (TEWL) by 16.2 and 25.7%, respectively, and maintained a digestive efficiency of about 70%. We found no support for the idea that reduced RMR in oryx correlated with a decreased thyroid hormone concentration in plasma. At the end of the 5 months acclimation, oryx continued to mobilize fatty acids to fuel metabolism, and did not use protein breakdown as a major source of gluconeogenesis. Oryx in the experimental group reduced their water intake by 70% and maintained constant plasma osmolality. They adjusted their water budget by reducing mass-specific TEWL, increasing urine osmolality and reducing urine volume by 40%, and excreting feces with <50% water content. Oryx have an unusually low TEWL compared with other arid-zone ungulates; both hydrated and water-deprived individuals have TEWL values, 51.7 and 39.3%, respectively, of allometric predictions for arid-zone ungulates. PMID:16283332

  6. Physiological acclimation of a desert antelope, Arabian oryx (Oryx leucoryx), to long-term food and water restriction.

    PubMed

    Ostrowski, Stéphane; Williams, Joseph B; Mésochina, Pascal; Sauerwein, Helga

    2006-03-01

    Desert mammals often experience scarcity of drinking water and food for prolonged periods. In this study, the first long-term acclimation experiment in a non-domesticated desert-adapted ungulate, we investigated the mechanisms used by the Arabian oryx Oryx leucoryx, to adjust its physiology to progressive food and water restriction over 5 months, an experimental regimen and time course chosen to mimic what it typically experiences between spring and late summer in the desert. At the end of the acclimation period, oryx consumed less than one and half of food and water of animals in the control group and lost 8.2+/-2.6% of their initial body mass. Experimental animals reduced their mass-specific resting metabolic rate (RMR) and total evaporative water loss (TEWL) by 16.2 and 25.7%, respectively, and maintained a digestive efficiency of about 70%. We found no support for the idea that reduced RMR in oryx correlated with a decreased thyroid hormone concentration in plasma. At the end of the 5 months acclimation, oryx continued to mobilize fatty acids to fuel metabolism, and did not use protein breakdown as a major source of gluconeogenesis. Oryx in the experimental group reduced their water intake by 70% and maintained constant plasma osmolality. They adjusted their water budget by reducing mass-specific TEWL, increasing urine osmolality and reducing urine volume by 40%, and excreting feces with <50% water content. Oryx have an unusually low TEWL compared with other arid-zone ungulates; both hydrated and water-deprived individuals have TEWL values, 51.7 and 39.3%, respectively, of allometric predictions for arid-zone ungulates.

  7. Physiological and blood biochemical variables in horses exercising on a treadmill submerged in water.

    PubMed

    Lindner, A; Wäschle, S; Sasse, H H L

    2012-08-01

    The blood lactate concentration (LA) and heart rate (HR) of 10 horses exercising in water on a treadmill were examined. With the water at 10 and 50% of the withers height (WH), the blood LA increased up to mean values around 1.9 mm during the standardized exercise test (SET) until after step 3 of 5 (each step lasted 5 min, speed increasing step by step). Thereafter, blood LA of horses remained constant, while with the water at 80% of WH, the blood LA decreased from the mean peak of 2.16 ± 0.62 mm after the 4th step. The HR of the horses increased to 132 ± 14 beats/min until the 3rd step of SET with the water at 10% of WH, up to the 2nd step with the water at 50% (134 ± 10 beats/min) and up to the 1st step only with the water at 80% of WH (134 ± 10 beats/min). In another SET, horses were exercised five times for 5 min at the maximal attainable speed of 5.5 m/s in water at 20% of the withers height in step 1, 35% in step 2, 49% in step 3, 63% in step 4 and 77% in step 5. On using this SET, blood LA increased to 1.91 ± 0.25 mm until after the 2nd step and decreased after the 3rd step. The HR increased between before commencing SET and the 1st step (143 ± 13 beats/min) and remained constant thereafter. In conclusion, increasing water height and speed of exercise does not augment continuously blood LA and HR of horses exercising in water treadmills.

  8. Separation characteristics of multistage water/hydrogen exchange column for water detritiation in fusion reactors

    SciTech Connect

    Yamanishi, T.; Okuno, K.

    1995-10-01

    A simulation code of multistage chemical exchange columns has been developed. The sieve trays for liquid-vapor scrubbing and the catalyst beds for vapor-hydrogen exchange reactions are alternately piled within the column. The code deals with all the twelve molecular species of hydrogen gas and water; and is based on the Newton-Raphson method. The characteristics of the column were discussed from the calculated results by this code such as effects of temperature and pressure. Similar to the distillation columns, the phase flow rates within the column (hydrogen gas and water vapor) and product flow rates have large effects on the separation performance of the column. A control method of the column was also proposed from these calculated results. 9 refs., 5 figs., 4 tabs.

  9. Growth and physiological responses of tree seedlings to experimental manipulation of light and water

    SciTech Connect

    Huston, M.A.; Holmgren, M.

    1995-06-01

    Seedlings of two tree species with similar tolerance to soil water and nutrient levels, but contrasting tolerance to shade (Acer saccharum and Liriodendron tulipifera) were grown in shade houses under 5 light levels (27%, 17%, 12%, 5%, and 1%) and three soil water regimes (5-9%, 11-15%, and >20%). Soil, light, and water conditions were representative of those in the Walker Branch Throughfall Displacement Experiment, where the same species are being monitored under field conditions. Treatments were maintained from mid-June through October, when all plants were harvested for determination of biomass allocation patterns. The only mortality occurred among the tulip poplars, but there was a significant interaction effect of the treatments on leaf area, total biomass, and allocation patterns. Highest growth rates in both species occurred at 17% light in the highest water treatment, with the 27% treatment showing reduced growth, perhaps due to photoinhibition. Gas exchange measurements indicated that the light compensation point increased under dry conditions.

  10. Estimation of turbulence characteristic scales in a water cell

    NASA Astrophysics Data System (ADS)

    Kulikov, Victor A.; Andreeva, Maria S.; Shmalhausen, Victor I.

    2012-10-01

    Turbulence is one of the key factors responsible for light beam distortions while its propagation through randomly inhomogeneous medium such as the atmosphere. Many common methods of turbulence study are based on the phase or amplitude analyses of the lightwave that have passed through turbulent medium. The significant role of explicit account of the inner and the outer scales in experimental data description is well known. We propose an optical method of turbulence characteristic scales estimation using phase data from Shack-Hartmann sensor obtained of a single laser beam. The method is based on the sequential analysis of normalized correlation functions of Zernike coefficients. It allows the excluding of the structural constant of refractive index value from the analysis and reduces the solution of a two-parameter problem to sequential solution of two single-parameter problems. The method has been applied to analyze the results of measurements performed in a water cell with created turbulence. A horizontal flow was induced to simulate turbulence driftage. It is shown that taking into account the inner scale is necessary for fitting of correlations of the third-order Zernike modes in the experimental error limits for lm/D=0.5 or higher values (lm - the inner scale, D- aperture diameter). Inner scale estimations did not depend on the flow or changes in the temperature difference. We have shown also that taking into account the outer scale is necessary for fitting of experimental correlations of the first-order Zernike modes in the experimental error limits when L0/D<50 (L0 - the outer scale).

  11. Linking nitrifying biofilm characteristics and nitrification performance in moving-bed biofilm reactors for polluted raw water pretreatment.

    PubMed

    Zhang, Shuangfu; Wang, Yayi; He, Weitao; Xing, Meiyan; Wu, Min; Yang, Jian; Gao, Naiyun; Sheng, Guangyao; Yin, Daqiang; Liu, Shanhu

    2013-10-01

    Biofilm physiology was characterized by four biofilm constituents, i.e., polysaccharides, proteins (PN), humic-like substances and phospholipids (PL), for the first time to explore the relationships between biofilm characteristics and nitrification performance in moving-bed biofilm reactors (MBBRs) designed for pretreatment of polluted raw surface water for potable supply. The biofilm compositions depended highly on the balance of microbial decay and nitrification processes. The increased ammonia loading greatly regulated the community structure, promoting the dominance of nitrifiers and their proportions in the nitrifying biofilm. Nitrification rate and activity correlated linearly with the fractions of volatile solids (VS), PN and PL, which were related to nitrification processes in the biofilm. The specific biofilm activity demonstrated an exponential-asymptotic relationship with ratios of PN/VS and PL/VS. Thus, analyzing biofilm characteristics can be valid for estimating nitrification performance in MBBRs, and may offer engineers with basis to optimize MBBR design and operation.

  12. Azospirillum and arbuscular mycorrhizal colonization enhance rice growth and physiological traits under well-watered and drought conditions.

    PubMed

    Ruíz-Sánchez, Michel; Armada, Elisabet; Muñoz, Yaumara; García de Salamone, Inés E; Aroca, Ricardo; Ruíz-Lozano, Juan Manuel; Azcón, Rosario

    2011-07-01

    The response of rice plants to inoculation with an arbuscular mycorrhizal (AM) fungus, Azospirillum brasilense, or combination of both microorganisms, was assayed under well-watered or drought stress conditions. Water deficit treatment was imposed by reducing the amount of water added, but AM plants, with a significantly higher biomass, received the same amount of water as non-AM plants, with a poor biomass. Thus, the water stress treatment was more severe for AM plants than for non-AM plants. The results showed that AM colonization significantly enhanced rice growth under both water conditions, although the greatest rice development was reached in plants dually inoculated under well-watered conditions. Water level did not affect the efficiency of photosystem II, but both AM and A. brasilense inoculations increased this value. AM colonization increased stomatal conductance, particularly when associated with A. brasilense, which enhanced this parameter by 80% under drought conditions and by 35% under well-watered conditions as compared to single AM plants. Exposure of AM rice to drought stress decreased the high levels of glutathione that AM plants exhibited under well-watered conditions, while drought had no effect on the ascorbate content. The decrease of glutathione content in AM plants under drought stress conditions led to enhance lipid peroxidation. On the other hand, inoculation with the AM fungus itself increased ascorbate and proline as protective compounds to cope with the harmful effects of water limitation. Inoculation with A. brasilense also enhanced ascorbate accumulation, reaching a similar level as in AM plants. These results showed that, in spite of the fact that drought stress imposed by AM treatments was considerably more severe than non-AM treatments, rice plants benefited not only from the AM symbiosis but also from A. brasilense root colonization, regardless of the watering level. However, the beneficial effects of A. brasilense on most of the

  13. Effects of hot tea, coffee and water ingestion on physiological responses and mood: the role of caffeine, water and beverage type.

    PubMed

    Quinlan, P; Lane, J; Aspinall, L

    1997-11-01

    Psychopharmacological studies using caffeinated beverages or caffeine have rarely considered temporal effects on psychological and physiological function or the specific contribution of caffeine, hot water, or beverage type to the observed effects. The effect of 400 ml hot tea, coffee, and water consumption on systolic and diastolic blood pressure (SBP and DBP), heart rate, skin conductance (a measure of sympathetic nervous system activation), skin temperature, salivary cortisol, and mood were monitored in 16 healthy caffeine-withdrawn (14 h) subjects in a complete crossover design. Beverages were ingested with/without 100 mg caffeine and milk (tea/coffee only). Hot beverage ingestion rapidly increased skin conductance and temperature (+1.7 degrees C) with peak effects observed only 10-30 min post-consumption. Caffeine in the beverage rapidly augmented skin conductance responses but, in contrast to the effect of hot water, reduced the skin temperature response and increased SBP (+2.8 mmHg) and DBP (+2.1 mmHg) 30-60 min post-consumption. Both caffeine and milk addition to beverages independently improved mood and reduced anxiety 30 and 60 min post-consumption. Milk addition had no other effects apart from attenuating the transient increase in physiological responses associated with the drinking phase. There were no effects of beverage consumption on salivary cortisol or of beverage vehicle on salivary caffeine levels, the latter indicating that caffeine pharmacokinetics was similar in both tea and coffee, and not different from caffeinated water. In keeping with this, the responses to tea and coffee ingestion were similar and largely accounted for by the effects of hot water and caffeine. However, tea potentiated the increase in skin temperature compared to coffee and water indicative of a greater vasodilatory response plausibly related to the presence of flavonoids in tea. We conclude that ingestion of hot caffeinated beverages stimulates physiological processes

  14. The physiological responses of Vallisneria natans to epiphytic algae with the increase of N and P concentrations in water bodies.

    PubMed

    Song, Yu-Zhi; Wang, Jin-Qi; Gao, Yong-Xia; Xie, Xue-Jian

    2015-06-01

    To reveal the mechanism of submerged plants decline in progressively eutrophicated freshwaters, physiological responses of Vallisneria natans to epiphytic algae were studied in simulation lab by measuring plant physiological indexes of chlorophyll content, malondialdehyde (MDA) content, and superoxide dismutase (SOD) activity based on a 2 × 4 factorial design with two epiphytic conditions (with epiphytic algae and without) and four levels of N and P concentrations in water (N-P[mg.L(-1)]: 0.5, 0.05; 2.5, 0.25; 4.5, 0.45; 12.5, 1.25). Compared with control (non-presence of epiphytic algae), chlorophyll contents of V. natans were significantly decreased (p < 0.01) for the presence of epiphytic algae under any concentrations of N and P in water bodies. While the presence of epiphytic algae induced peroxidation of membrane lipids, MDA contents of V. natans had significantly increased (p < 0.05) by comparing with control. SOD activity significantly enhanced (p < 0.05) with the presence of epiphytic algae in the treatments of T2 and T3 in the whole culture process by comparing with control, sometimes reaching an extremely significant level (p < 0.01). However, in the treatments of T1 and T4, SOD activity had no obvious change with the presence of epiphytic algae (p < 0.05) by comparing with control. At the end of the experiment, the effects of epiphytic algae on chlorophyll content and SOD activity in the leaves of V. natans were increased at first and then decreased with the concentrations of N and P in water, and MDA content became higher with the increase of N and P. concentrations. Repeated measurement data testing showed that the effects of epiphytic algae on the chlorophyll content and MDA content and SOD activity were significant, respectively (p < 0.001), the effects of epiphytic algae were combining with effects of concentrations of N and P (p < 0.001), respectively, and their interaction (p < 0.001). Our observations

  15. The physiological responses of Vallisneria natans to epiphytic algae with the increase of N and P concentrations in water bodies.

    PubMed

    Song, Yu-Zhi; Wang, Jin-Qi; Gao, Yong-Xia; Xie, Xue-Jian

    2015-06-01

    To reveal the mechanism of submerged plants decline in progressively eutrophicated freshwaters, physiological responses of Vallisneria natans to epiphytic algae were studied in simulation lab by measuring plant physiological indexes of chlorophyll content, malondialdehyde (MDA) content, and superoxide dismutase (SOD) activity based on a 2 × 4 factorial design with two epiphytic conditions (with epiphytic algae and without) and four levels of N and P concentrations in water (N-P[mg.L(-1)]: 0.5, 0.05; 2.5, 0.25; 4.5, 0.45; 12.5, 1.25). Compared with control (non-presence of epiphytic algae), chlorophyll contents of V. natans were significantly decreased (p < 0.01) for the presence of epiphytic algae under any concentrations of N and P in water bodies. While the presence of epiphytic algae induced peroxidation of membrane lipids, MDA contents of V. natans had significantly increased (p < 0.05) by comparing with control. SOD activity significantly enhanced (p < 0.05) with the presence of epiphytic algae in the treatments of T2 and T3 in the whole culture process by comparing with control, sometimes reaching an extremely significant level (p < 0.01). However, in the treatments of T1 and T4, SOD activity had no obvious change with the presence of epiphytic algae (p < 0.05) by comparing with control. At the end of the experiment, the effects of epiphytic algae on chlorophyll content and SOD activity in the leaves of V. natans were increased at first and then decreased with the concentrations of N and P in water, and MDA content became higher with the increase of N and P. concentrations. Repeated measurement data testing showed that the effects of epiphytic algae on the chlorophyll content and MDA content and SOD activity were significant, respectively (p < 0.001), the effects of epiphytic algae were combining with effects of concentrations of N and P (p < 0.001), respectively, and their interaction (p < 0.001). Our observations

  16. Water quality and streamflow characteristics, Raritan River Basin, New Jersey

    USGS Publications Warehouse

    Anderson, Peter W.; Faust, Samuel Denton

    1974-01-01

    The findings of a problem-oriented river-system investigation of the stream-quality and streamflow characteristics of the Raritan River basin (1,105 square miles or 2,862 square kilometers drainage area) are described. The investigation covers mainly the period 1955-72. Precipitation in the basin is classified as ample and averages 47 inches or 120 centimeters per year (3-5 inches or 8-12 centimeters per month). During the study period four general precipitation trends were noted: less than normalin 1955-61 and 1966-70; extreme drought in 1962-66; and above normal in 1971-72. Analyses of streamflow measurements at eight gaging stations indicate a general trend toward lower flows during the study period, which is attributed to generally lower than normal precipitation. Highest flows were observed in 1958, concurrent with maximum annual precipitation; whereas lowest flows were observed in 1965 during extreme drought conditions. Non-tidal streams in the basin are grouped into three general regions of similar chemical quality based upon predominant constituents and dissolved-solids concentration during low-flow conditions. The predominant cations in solution in all regions are calcium and magnesium (usually exceeding 60 percent of total cation content). In headwater streams of the North and South Branch Raritan Rivers, bicarbonate is the predominant anion; a combination of sulfate, chloride, and nitrate are the predominant anions in the other two regions. The dissolved-solids concentration of streams in areas little influenced by man's activities generally range from 40 to 200 mg/L. Those in areas influenced by man often range much higher sometimes exceeding 800 mg/L. Suspended-sediment yields in the basin range from 25 to 500 tons per square mile annually. The water quality of the Raritan River and most tributaries above Manville (784 square miles of 2,030 square kilometers drainage area) generally is good for most industrial, domestic, and recreational uses, although

  17. Physiology and proteomics of the water-deficit stress response in three contrasting peanut genotypes.

    PubMed

    Kottapalli, Kameswara Rao; Rakwal, Randeep; Shibato, Junko; Burow, Gloria; Tissue, David; Burke, John; Puppala, Naveen; Burow, Mark; Payton, Paxton

    2009-04-01

    Peanut genotypes from the US mini-core collection were analysed for changes in leaf proteins during reproductive stage growth under water-deficit stress. One- and two-dimensional gel electrophoresis (1- and 2-DGE) was performed on soluble protein extracts of selected tolerant and susceptible genotypes. A total of 102 protein bands/spots were analysed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and by quadrupole time-of-flight tandem mass spectrometry (Q-TOF MS/MS) analysis. Forty-nine non-redundant proteins were identified, implicating a variety of stress response mechanisms in peanut. Lipoxygenase and 1l-myo-inositol-1-phosphate synthase, which aid in inter- and intracellular stress signalling, were more abundant in tolerant genotypes under water-deficit stress. Acetyl-CoA carboxylase, a key enzyme of lipid biosynthesis, increased in relative abundance along with a corresponding increase in epicuticular wax content in the tolerant genotype, suggesting an additional mechanism for water conservation and stress tolerance. Additionally, there was a marked decrease in the abundance of several photosynthetic proteins in the tolerant genotype, along with a concomitant decrease in net photosynthesis in response to water-deficit stress. Differential regulation of leaf proteins involved in a variety of cellular functions (e.g. cell wall strengthening, signal transduction, energy metabolism, cellular detoxification and gene regulation) indicates that these molecules could affect the molecular mechanism of water-deficit stress tolerance in peanut. PMID:19143990

  18. Physiology and proteomics of the water-deficit stress response in three contrasting peanut genotypes.

    PubMed

    Kottapalli, Kameswara Rao; Rakwal, Randeep; Shibato, Junko; Burow, Gloria; Tissue, David; Burke, John; Puppala, Naveen; Burow, Mark; Payton, Paxton

    2009-04-01

    Peanut genotypes from the US mini-core collection were analysed for changes in leaf proteins during reproductive stage growth under water-deficit stress. One- and two-dimensional gel electrophoresis (1- and 2-DGE) was performed on soluble protein extracts of selected tolerant and susceptible genotypes. A total of 102 protein bands/spots were analysed by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and by quadrupole time-of-flight tandem mass spectrometry (Q-TOF MS/MS) analysis. Forty-nine non-redundant proteins were identified, implicating a variety of stress response mechanisms in peanut. Lipoxygenase and 1l-myo-inositol-1-phosphate synthase, which aid in inter- and intracellular stress signalling, were more abundant in tolerant genotypes under water-deficit stress. Acetyl-CoA carboxylase, a key enzyme of lipid biosynthesis, increased in relative abundance along with a corresponding increase in epicuticular wax content in the tolerant genotype, suggesting an additional mechanism for water conservation and stress tolerance. Additionally, there was a marked decrease in the abundance of several photosynthetic proteins in the tolerant genotype, along with a concomitant decrease in net photosynthesis in response to water-deficit stress. Differential regulation of leaf proteins involved in a variety of cellular functions (e.g. cell wall strengthening, signal transduction, energy metabolism, cellular detoxification and gene regulation) indicates that these molecules could affect the molecular mechanism of water-deficit stress tolerance in peanut.

  19. Anatomical and physiological regulation of post-fire carbon and water exchange in canopies of two resprouting Eucalyptus species.

    PubMed

    Turnbull, Tarryn L; Buckley, Thomas N; Barlow, Alexandra M; Adams, Mark A

    2014-10-01

    The great majority of Eucalyptus spp. are facultative resprouters, and they dominate the eucalypt forests of Australia. Despite this numeric and geographic dominance, there is a general lack of knowledge of their capacity for carbon capture and water loss during canopy reinstation. After a crown-removing fire, we measured leaf-level determinants of carbon and water flux in resprouting canopies of Eucalyptus dives and E. radiata over the 3 years that followed. Leaf anatomy and physiology changed markedly during canopy reinstation, and leaves produced in the second year (2010) were distinct from those produced later. Leaves produced in 2010 were thicker (all measures of leaf anatomy), yet more porous (increased intercellular airspace), causing specific leaf area also to be greater. Indicators of heterotrophic activity, leaf respiration rate and light compensation point, were twofold greater in 2010, whereas all measures of photosynthetic capacity were greatest in leaves produced in 2011 and 2012. Whilst stomatal density, vein density and leaf hydraulic conductance all progressively decreased with time, neither leaf water status nor carbon isotope discrimination were affected. We conclude that canopy reinstation is primarily limited by pre-fire carbon stores, rather than by post-fire edaphic conditions (e.g., water availability), and thus argue that capacity for recovery is directly linked to pre-fire forest health.

  20. A Physiological Stimulating Factor of Water Intake during and after Dry Forage Feeding in Large-type Goats

    PubMed Central

    Van Thang, Tran; Sunagawa, Katsunori; Nagamine, Itsuki; Kishi, Tetsuya; Ogura, Go

    2012-01-01

    plasma osmolality in the second hour of the 2 h feeding period is the main physiological stimulating factor of water intake during and after dry forage feeding in large-type goats. PMID:25049591

  1. Physiological ecology of desert iguana (Dipsosaurus dorsalis) eggs: temperature and water relations

    SciTech Connect

    Muth, A.

    1980-12-01

    The soil environment imposes constraints on the timing of oviposition and the location of suitable sites for egg burrows of the desert iguana (Dipsosaurus dorsalis). The effects of temperature and water potential on the developmental period and hatching success of eggs were determined. Eggs hatch normally between 28/sup 0/ and 38/sup 0/C at environmental water potentials between -50 and -1500 kPa. Predictions were derived for the timing and placement of egg clutches based on soil water potential and temperature profiles measured in the field and on the results of laboratory incubation experiments. The results suggest that egg burrows should be located at depths >22 cm in washes or possibly in sparsely vegetated areas away from creosote bushes. The biogeography of desert iguanas within the United States is discussed in relation to soil environments and tolerances of eggs. The physical factors affecting incubation may limit the geographical range of desert iguanas.

  2. Physiologically Based Pharmacokinetic modeling of the temperature-dependent dermal absorption of chloroform by humans following bath water exposures

    SciTech Connect

    Corley, Rick A. ); Gordon, Syd M.; Wallace, Lance A.

    2000-01-14

    The kinetics of chloroform in the exhaled breath of human volunteers exposed skin-only via bath water (concentrations < 100 ppb) were analyzed using a physiologically based pharmacokinetic (PBPK) model. Significant increases in exhaled chloroform (and thus bioavailability) were observed as exposure temperatures were increased from 30 to 40?C. The blood flows to the skin and effective skin permeability coefficients (Kp) were both varied to reflect the temperature-dependent changes in physiology and exhalation kinetics. At 40?C, no differences were observed between males and females. Therefore, Kp?s were determined ({approx}0.06 cm/hr) at a skin blood flow rate of 18% of the cardiac output. At 30 and 35?C, males exhaled more chloroform than females resulting in lower effective Kp?s calculated for females. At these lower temperatures, the blood flow to the skin was also reduced. Total amounts of chloroform absorbed averaged 41.9 and 43.6 mg for males and 11.5 and 39.9 mg for females exposed at 35 and 40?C, respectively. At 30?C, only 2/5 males and 1/5 females had detectable concentrations of chloroform in their exhaled breath. For perspective, the total intake of chloroform would have ranged from 79 - 194 mg if the volunteers had consumed 2 L of water orally at the concentrations used in this study. Thus, the relative contribution of dermal uptake of chloroform to the total body burdens associated with bathing for 30 min and drinking 2 L of water (ignoring contributions from inhalation exposures) was predicted to range from 1-28% depending on the temperature of the bath.

  3. Comparison of Water Turbine Characteristics using Different Blades in Darrieus Water Turbines used for Tidal Current Generations

    NASA Astrophysics Data System (ADS)

    Shiono, Mitsuhiro; Suzuki, Katsuyuki; Kiho, Seiji

    The use of renewable energies has been focused on for preserving environments and coping with the shortage of future energy supplies. In oceans, a tide reverses its current direction every six hours, and the current velocity changes into a sine wave after a period of time. Tidal current generation uses a generator to produce energy, changing the kinetic energy of current into a turning force by setting a water turbine in the tidal current. Therefore, it is considered to be very advantageous to use a water turbine that can always revolve in a fixed direction without any influence from tidal current directions. Water turbines with these characteristics are known as Darrieus water turbines. The Darrieus water turbines were modified for water from turbines originally developed for windmills. Darrieus water turbines have a difficulty in starting, but these days Darrieus water turbines have been developed with spiral blades, which make it easy to get the turbines started. However, there are very few reports regarding Darrieus water turbines with spiral blades, and therefore their characteristics are unknown. From the above points of view, this study devises and investigates spiral blade-Darrieus water turbines to clarify their characteristics through hydrographic experiments, and at the same time, it compares the characteristics of spiral-blade Darrieus water turbines with those of straight-blade ones.

  4. Effect of Salinity on Biomass Yield and Physiological and Stem-Root Anatomical Characteristics of Purslane (Portulaca oleracea L.) Accessions

    PubMed Central

    Juraimi, Abdul Shukor; Rafii, M. Y.; Abdul Hamid, Azizah

    2015-01-01

    13 selected purslane accessions were subjected to five salinity levels 0, 8, 16, 24, and 32 dS m−1. Salinity effect was evaluated on the basis of biomass yield reduction, physiological attributes, and stem-root anatomical changes. Aggravated salinity stress caused significant (P < 0.05) reduction in all measured parameters and the highest salinity showed more detrimental effect compared to control as well as lower salinity levels. The fresh and dry matter production was found to increase in Ac1, Ac9, and Ac13 from lower to higher salinity levels but others were badly affected. Considering salinity effect on purslane physiology, increase in chlorophyll content was seen in Ac2, Ac4, Ac6, and Ac8 at 16 dS m−1 salinity, whereas Ac4, Ac9, and Ac12 showed increased photosynthesis at the same salinity levels compared to control. Anatomically, stem cortical tissues of Ac5, Ac9, and Ac12 were unaffected at control and 8 dS m−1 salinity but root cortical tissues did not show any significant damage except a bit enlargement in Ac12 and Ac13. A dendrogram was constructed by UPGMA based on biomass yield and physiological traits where all 13 accessions were grouped into 5 clusters proving greater diversity among them. The 3-dimensional principal component analysis (PCA) has also confirmed the output of grouping from cluster analysis. Overall, salinity stressed among all 13 purslane accessions considering biomass production, physiological growth, and anatomical development Ac9 was the best salt-tolerant purslane accession and Ac13 was the most affected accession. PMID:25802833

  5. INSTABILITY OF THE WATER DISINFECTION BY-PRODUCT DIBROMOACETONITRILE UNDER PHYSIOLOGICAL CONDITIONS: KINETICS AND PRODUCT CHARACTERIZATION

    EPA Science Inventory

    Dibromoacetonitrile (DBAN) is a prevalent haloacetonitrile formed as a byproduct of water chlorination. DBAN is toxic in vivo and genotoxic in vitro and is a mouse skin tumor initiator. However, little is known about its mechanisms of toxicity or genotoxicity or its stability. Du...

  6. Physiology and proteomics of the water-deficit stress response in three contrasting peanut genotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut (Arachis hypogaea L.) accessions from the US mini core collection were analyzed for differentially expressed leaf proteins during reproductive stage under water-deficit stress. Accessions showing tolerant and susceptible responses to stress were selected based on a bioassay involving chloroph...

  7. Impact of water and feed deprivation on physiological parameters in steers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A report in rats demonstrated that dehydration as the result of 8 d of water deprivation increased leakage of endotoxin from the intestine (Zurovsky and Barbiro, 2000 Experimental and toxicologic pathology 52:37-42). Given the large number of gram negative bacteria in the rumen of cattle, a much sho...

  8. Rating of Perceived Exertion and Physiological Responses in Water-Based Exercise

    PubMed Central

    Pinto, Stephanie Santana; Alberton, Cristine Lima; Zaffari, Paula; Cadore, Eduardo Lusa; Kanitz, Ana Carolina; Liedtke, Giane Veiga; Tartaruga, Marcus Peikriszwili; Kruel, Luiz Fernando Martins

    2015-01-01

    The aim of the present study was to relate the overall rating of perceived exertion (RPE-overall) with cardiorespiratory and neuromuscular variables during stationary running with the elbow flexion/extension performed with water-floating equipment. The sample consisted of eleven women that performed the water-based exercise at submaximal cadences. The heart rate, oxygen uptake, ventilation, and electromyographic signal (EMG) from biceps brachii (%EMG BB), triceps brachii (%EMG TB), biceps femoris (%EMG BF) and rectus femoris (%EMG RF) muscles were measured during the exercise, and the overall RPE was measured immediately following its completion. The Pearson product-moment linear correlation was used to investigate associations between the variables analyzed in the present study. Significant relationships were observed between the RPE-overall and all the cardiorespiratory variables, with the r values ranging from 0.60 to 0.70 (p<0.05). In addition, the RPE-overall showed a significant (p<0.05) relationship with %EMG BB (r=0.55) and %EMG BF (r=0.50). These results suggest an association between the RPE-overall with all cardiorespiratory and two neuromuscular variables during the execution of a water-based aerobic exercise using water-floating equipment. PMID:26839610

  9. Facing the River Gauntlet: Understanding the Effects of Fisheries Capture and Water Temperature on the Physiology of Coho Salmon

    PubMed Central

    Raby, Graham D.; Clark, Timothy D.; Farrell, Anthony P.; Patterson, David A.; Bett, Nolan N.; Wilson, Samantha M.; Willmore, William G.; Suski, Cory D.; Hinch, Scott G.; Cooke, Steven J.

    2015-01-01

    An improved understanding of bycatch mortality can be achieved by complementing field studies with laboratory experiments that use physiological assessments. This study examined the effects of water temperature and the duration of net entanglement on physiological disturbance and recovery in coho salmon (Oncorhynchus kisutch) after release from a simulated beach seine capture. Heart rate was monitored using implanted electrocardiogram biologgers that allowed fish to swim freely before and after release. A subset of fish was recovered in respirometers to monitor metabolic recovery, and separate groups of fish were sacrificed at different times to assess blood and white muscle biochemistry. One hour after release, fish had elevated lactate in muscle and blood plasma, depleted tissue energy stores, and altered osmoregulatory status, particularly in warmer (15 vs. 10°C) and longer (15 vs. 2 min) capture treatments. A significant effect of entanglement duration on blood and muscle metabolites remained after 4 h. Oxygen consumption rate recovered to baseline within 7–10 h. However, recovery of heart rate to routine levels was longer and more variable, with most fish taking over 10 h, and 33% of fish failing to recover within 24 h. There were no significant treatment effects on either oxygen consumption or heart rate recovery. Our results indicate that fishers should minimize handling time for bycatch and maximize oxygen supply during crowding, especially when temperatures are elevated. Physiological data, such as those presented here, can be used to understand mechanisms that underlie bycatch impairment and mortality, and thus inform best practices that ensure the welfare and conservation of affected species. PMID:25901952

  10. Effects of environmental parameters, leaf physiological properties and leaf water relations on leaf water delta18O enrichment in different Eucalyptus species.

    PubMed

    Kahmen, Ansgar; Simonin, Kevin; Tu, Kevin P; Merchant, Andrew; Callister, Andrew; Siegwolf, Rolf; Dawson, Todd E; Arndt, Stefan K

    2008-06-01

    Stable oxygen isotope ratios (delta18O) have become a valuable tool in the plant and ecosystem sciences. The interpretation of delta18O values in plant material is, however, still complicated owing to the complex interactions among factors that influence leaf water enrichment. This study investigated the interplay among environmental parameters, leaf physiological properties and leaf water relations as drivers of the isotopic enrichment of leaf water across 17 Eucalyptus species growing in a common garden. We observed large differences in maximum daily leaf water delta18O across the 17 species. By fitting different leaf water models to these empirical data, we determined that differences in leaf water delta18O across species are largely explained by variation in the Péclet effect across species. Our analyses also revealed that species-specific differences in transpiration do not explain the observed differences in delta18O while the unconstrained fitting parameter 'effective path length' (L) was highly correlated with delta18O. None of the leaf morphological or leaf water related parameters we quantified in this study correlated with the L values we determined even though L was typically interpreted as a leaf morphological/anatomical property. A sensitivity analysis supported the importance of L for explaining the variability in leaf water delta18O across different species. Our investigation highlighted the importance of future studies to quantify the leaf properties that influence L. Obtaining such information will significantly improve our understanding of what ultimately determines the delta18O values of leaf water across different plant species. PMID:18208514

  11. Oxygen flux as an indicator of physiological stress in aquatic organisms: a real-time biomonitoring system of water quality

    NASA Astrophysics Data System (ADS)

    Sanchez, Brian C.; Yale, Gowri; Chatni, Rameez; Ochoa-Acuña, Hugo G.; Porterfield, D. Marshall; Mclamore, Eric S.; Sepúlveda, María S.

    2009-05-01

    The detection of harmful chemicals and biological agents in real time is a critical need for protecting water quality. We studied the real-time effects of five environmental contaminants with differing modes of action (atrazine, pentachlorophenol, cadmium chloride, malathion, and potassium cyanide) on respiratory oxygen consumption in 2-day post-fertilization fathead minnow (Pimephales promelas) eggs. Our objective was to assess the sensitivity of fathead minnow eggs using the self-referencing micro-optrode technique to detect instantaneous changes in oxygen consumption after brief exposures to low concentrations of contaminants. Oxygen consumption data indicated that the technique is indeed sensitive enough to reliably detect physiological alterations induced by all contaminants. After 2 h of exposure, we identified significant increases in oxygen consumption upon exposure to pentachlorophenol (100 and 1000 μg/L), cadmium chloride (0.0002 and 0.002 μg/L), and atrazine (150 μg/L). In contrast, we observed a significant decrease in oxygen flux after exposures to potassium cyanide (5.2, 22, and 44 μg/L) and atrazine (1500 μg/L). No effects were detected after exposures to malathion (200 and 340 μg/L). We have also tested the sensitivity of Daphnia magna embryos as another animal model for real-time environmental biomonitoring. Our results are so far encouraging and support further development of this technology as a physiologically coupled biomonitoring tool for the detection of environmental toxicants.

  12. Environmental Physiology of the Mangrove Rivulus, Kryptolebias marmoratus, A Cutaneously Breathing Fish That Survives for Weeks Out of Water

    PubMed Central

    Wright, Patricia A.

    2012-01-01

    The mangrove rivulus (Kryptolebias marmoratus) is an excellent model species for understanding the physiological mechanisms that fish use in coping with extreme environmental conditions, particularly cutaneous exchange during prolonged exposure to air. Their ability to self-fertilize and produce highly homozygous lineages provides the potential for examining environmental influences on structures and related functions without the complications of genetic variation. Over the past 10 years or so, we have gained a broader understanding of the mechanisms K. marmoratus use to maintain homeostasis when out of water for days to weeks. Gaseous exchange occurs across the skin, as dramatic remodeling of the gill reduces its effective surface area for exchange. Ionoregulation and osmoregulation are maintained in air by exchanging Na+, Cl−, and H2O across skin that contains a rich population of ionocytes. Ammonia excretion occurs in part by cutaneous NH3 volatilization facilitated by ammonia transporters on the surface of the epidermis. Finally, new evidence indicates that cutaneous angiogenesis occurs when K. marmoratus are emersed for a week, suggesting a higher rate of blood flow to surface vessels. Taken together, these and other findings demonstrate that the skin of K. marmoratus takes on all the major functions attributed to fish gills, allowing them to move between aquatic and terrestrial environments with ease. Future studies should focus on variation in response to environmental changes between homozygous lineages to identify the genetic underpinnings of physiological responses. PMID:22693260

  13. Uptake and physiological response of crop plants irrigated with water containing RDX and TNT

    SciTech Connect

    Simini, M.; Checkai, R.T.

    1995-12-31

    Regulatory agencies have expressed concern about possible bioconcentration of TNT (2,4,6-trinitrotoluene) and RDX (cyclotrimethylenetrinitramine) in food and forage crops irrigated with contaminated groundwater. Field and home-garden crops grown in site-collected soil were irrigated with water containing RDX and TNT to simulate field conditions at Cornhusker Army Ammunition Plant (CAAP), Nebraska. Pots were watered in an environment-controlled greenhouse to field capacity throughout the life-cycle of each crop with 2, 20, and 100 ppb RDX; 2, 100, and 800 ppb TNT; 100 ppb RDX + 800 ppb TNT; or uncontaminated water in response to evapo-transpirative demand. Uptake of RDX in lettuce leaves, corn stover, and alfalfa shoots was positively correlated with treatment level, however, concentrations of RDX in these crops were generally equal to or below soil loading concentrations. RDX was not significantly (p = 0.05) taken up into tomato fruit, bush bean seeds and pods, radish roots, and soybean seeds. TNT was not significantly take up into tissues of any of the crops analyzed in this study. Yield and biomass of tomato fruit, bush bean fruit, corn stover, and soybean seeds were significantly (p = 0.05) less when irrigated with the RDX + TNT treatment compared to controls. Lettuce leaf, radish root, and alfalfa shoot yield and biomass were unaffected by treatment level. For site-specific criteria used in this study, RDX and TNT did not bioconcentrate in edible plant tissues. This is the first controlled study to investigate uptake of RDX and TNT in crops irrigated with water containing explosives concentrations commonly found in contaminated groundwater.

  14. Physiological properties of Scomber japonicus meat hydrolysate prepared by subcritical water hydrolysis.

    PubMed

    Choi, Jae-Suk; Moon, Hye Eun; Roh, Myong-Kyun; Ha, Yu-Mi; Lee, Bo-Bae; Cho, Kwang Keun; Choi, In Soon

    2016-01-01

    The health-beneficial biological activities, including antioxidant and tyrosinase inhibitory activities, of Scomber japonicus muscle protein hydrolysates prepared by subcritical water hydrolysis were investigated. After 5 min of subcritical hydrolysis at 140 degrees C, 59.76% of S. japonicus muscle protein was hydrolyzed, the highest degree of hydrolysis in all the groups were tested. According to the response surface methodology results, as the reaction temperature and reaction time became lower and shorter, the yield became higher. The highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity (90.63%) occurred in hydrolysates treated at 140 degrees C for 5 min, and the highest tyrosinase inhibitory activity (65.54%) was identified in hydrolysates treated at 200 degreesC for 15 min. Changes in the molecular weight distribution of S. japonicus muscle proteins after subcritical water hydrolysis were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Subcritical water hydrolysis is a suitable technique for obtaining S.japonicus muscle protein hydrolysates with useful biological activities, within a short time (5-15 min).

  15. Investigations on the physiological controls of water and saline intake in C57BL/6 mice.

    PubMed

    Johnson, Ralph F; Beltz, Terry G; Thunhorst, Robert L; Johnson, Alan Kim

    2003-08-01

    To examine the behavioral and neural control of body fluid homeostasis, water and saline intake of C57BL/6 mice was monitored under ad libitum conditions, after treatments that induce water or salt intake, and after ablation of the periventricular tissue of the anteroventral third ventricle (AV3V). Mice have nocturnal drinking that is most prevalent after the offset and before the onset of lights. When given ad libitum choice, C57BL/6 mice show no preference for saline over water at concentrations up to 0.9% NaCl and a progressive aversion to saline above that concentration. Systemic hypertonic saline, isoproterenol, and polyethylene glycol treatments are dipsogenic; however, systemic ANG II is not. Intracerebroventricular injections of both hypertonic saline and ANG II are dipsogenic, and diuretic treatment followed by a short period of sodium deprivation induces salt intake. After ablation of the AV3V, mice can be nursed to recovery from initial adipsia and, similar to rats, show chronic deficits to dipsogenic treatments. Taken together, the data indicate that mechanisms controlling thirst in response to cellular dehydration in C57BL/6 mice are similar to rats, but there are differences in the efficacy of extracellular dehydration-related mechanisms, especially for systemic ANG II, controlling thirst and salt appetite.

  16. Hydrogeochemical characteristics of water intakes from groundwater sources in Seversk

    NASA Astrophysics Data System (ADS)

    Karmalov, A. I.; Dutova, E. M.; Vologdina, I. V.; Pokrovsky, D. S.; Pokrovskiy, V. D.; Kuzevanov, K. K.

    2016-09-01

    The article describes the hydrogeochemical environment behavior analysis of groundwater intake which, in its turn. provides the utility and drinking water supply for Seversk. The reasons for temporary changes of the hydrogeochemical aquifer indicators in the producing areas have been highlighted. The main factor could be upset hydrodynamic conditions during long-term operation. Changed hydrogeochemical indicators have been revealed not only during the technological water treatment process but also during water transportation to consumers. Chemical composition water changes are related to secondary mineral and sludge formation on technological equipment. Precipitation is a polymineral mixture predominantly a ferrous phase. whereas phosphate and carbonate phases are secondary. Clay minerals are also found.

  17. Effects of temperature and light intensity on growth and physiology in purple root water hyacinth and common water hyacinth (Eichhornia crassipes).

    PubMed

    Shu, Xiao; Zhang, QuanFa; Wang, WeiBo

    2014-11-01

    In this study, the interaction between temperature and light intensity was investigated in common water hyacinth (CWH) and purple root water hyacinth (PRWH). Effects of different temperatures (11/5, 18/11, 25/18, and 32/25 °C day/night) simultaneously applied at various light intensities (100, 300, and 600 μmol m(-2) s(-1)) to the plants were detected by measuring changes in the root lengths, protein content, sugar content, malondialdehyde (MDA) content, photosynthesis, and dissolved oxygen (DO). Temperature and light intensity significantly influence the growth of water hyacinths, and there was significant interaction among these environmental factors. The results suggest that several environmental factors act synergistically on the growth and physiology of water hyacinths. The higher new root length (NRL) in PRWH indicated that its root growth capacity is higher than in CWH. The soluble sugar content in leaves of CWH was higher than PRWH, indicating that relatively higher sugar content in CWH to low-temperature stress may support its tolerant nature. Lower temperature and light intensity can stimulate the accumulation of MDA content. The net photosynthetic rate (Pn) in leaves of CWH was higher than PRWH. In low temperature, increase light intensity can stimulate the Pn of PRWH and CWH. In CWH and PRWH, Pn showed a similar trend as noted for stomatal conductance (Cond) and transpiration rate (Tr). The capacity of PRWH in adding oxygen to the water column is better than those of CWH.

  18. The physiological resilience of fern sporophytes and gametophytes: advances in water relations offer new insights into an old lineage

    PubMed Central

    Pittermann, Jarmila; Brodersen, Craig; Watkins, James E.

    2013-01-01

    Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have focused on the physiological capacity and stress tolerance of both the sporophyte and the gametophyte generations. In this review, we examine these insights through the lens of plant water relations, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and variously sized megaphylls are shared between ferns and more derived lineages, and offer an opportunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gametophyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic. PMID:23935601

  19. Spatiotemporal characteristics and water budget of water cycle elements in different seasons in northeast China

    NASA Astrophysics Data System (ADS)

    Zhou, Jie; Zhao, Jun-Hu; He, Wen-Ping; Zhi-Qiang, Gong

    2015-04-01

    In this paper, we study the spatiotemporal characteristics of precipitable water, precipitation, evaporation, and water-vapor flux divergence in different seasons over northeast China and the water balance of that area. The data used in this paper is provided by the European Center for Medium-Range Weather Forecasts (ECMWF). The results show that the spatial distributions of precipitable water, precipitation, and evaporation feature that the values of elements above in the southeastern area are larger than those in the northwestern area; in summer, much precipitation and evaporation occur in the Changbai Mountain region as a strong moisture convergence region; in spring and autumn, moisture divergence dominates the northeast of China; in winter, the moisture divergence and convergence are weak in this area. From 1979 to 2010, the total precipitation of summer and autumn in northeast China decreased significantly; especially from 1999 to 2010, the summer precipitation always demonstrated negative anomaly. Additionally, other elements in different seasons changed in a truly imperceptible way. In spring, the evaporation exceeded the precipitation in northeast China; in summer, the precipitation was more prominent; in autumn and winter, precipitation played a more dominating role than the evaporation in the northern part of northeast China, while the evaporation exceeded the precipitation in the southern part. The Interim ECMWF Re-Analysis (ERA-Interim) data have properly described the water balance of different seasons in northeast China. Based on ERA-Interim data, the moisture sinks computed through moisture convergence and moisture local variation are quite consistent with those computed through precipitation and evaporation, which proves that ERA-Interim data can be used in the research of water balance in northeast China. On a seasonal scale, the moisture convergence has a greater influence than the local moisture variation on a moisture sink, and the latter is

  20. Effect of Ar Ion Beam Implantation on Morphological and Physiological Characteristics of Liquorice (Glycyrrhiza uralensis Fisch) Under Short-Term Artificial Drought Conditions

    NASA Astrophysics Data System (ADS)

    Zhang, Xiangsheng; Wu, Lijun; Yu, Lixiang; Wei, Shenglin; Liu, Jingnan; Yu, Zengliang

    2007-04-01

    Ar+ ion beam with low energy of 30 keV was implanted into liquorice (Glycyrrhiza uralensis Fisch) seeds at the doses of 0, 600, 900 and 1200 × (2.6 × 1013) ions/cm2, respectively. The seeds were sowed in pots and after one month the plants were subjected to different drought conditions for two months. Then the plants' morphological and physiological characteristics, anti-oxidation enzymes and levels of endogenous hormones were investigated. The results showed that ion implantation at a proper dose can greatly enhance the liquorice seedlings' resistance against drought stress.

  1. [Elaboration of systematic position and some physiological characteristics of collection strains of Debaryomyces hansenii (Zopf) Looder et Kreger-Van Rij].

    PubMed

    Nahorna, S S; Babich, T V; Polishchuk, L V; Pidhors'kyĭ, V S

    2007-01-01

    Morphological and physiological properties of 52 strains of yeast Debaryomyces hansenii from the Ukrainian collection of microorganisms has been investigated. The belonging of 40 strains to the given species is confirmed. According to new classification 35 of them are referred to D. hansenii var. hansenii, five strains--to D.hansenii var. fabryi. It is shown, that assimilation of hydrocarbons and antagonistic properties are inherent in a small amount of strains. One half of the investigated debaryomycetes are riboflavin producers. The osmo- and galofility is inherent in all the investigated strains. These characteristics are proposed to be applied as additional ones in identification of these yeast. PMID:17427404

  2. Effects of triploidy induction on physiological and immunological characteristics of rainbow trout (Oncorhynchus mykiss) at early developmental stages (fertilized eggs, eyed eggs and fry).

    PubMed

    Salimian, Shekoofeh; Keyvanshokooh, Saeed; Salati, Amir Parviz; Pasha-Zanoosi, Hossein; Babaheydari, Samad Bahrami

    2016-02-01

    The aim of this study was to compare effects of triploidy induction on basal physiological and immunological characteristics in rainbow trout at three developmental stages including fertilized eggs, eyed eggs and fry. Eggs and milt were taken from eight females and six males. The gametes were pooled to minimize the individual differences. After insemination, the eggs were incubated at 10°C for 10min. Half of the fertilized eggs were then subjected to heat shock for 10min submerged in a 28°C water bath to induce triploidy. The remainder were incubated normally and used as diploid controls. Three batches of eggs were randomly selected from each group and were incubated at 10-11°C under the same environmental conditions in hatchery troughs until the fry stage. The first-feeding offspring were also reared under the same environmental and nutritional conditions for 38 days. Triplicate samples of 30 eggs (10 eggs per trough) from each group were selected 1.5h post-fertilization and at the eyed stage. Based on red blood cell analysis, nine diploid and nine triploid fish were also selected for study. The triploidy induction success rate was 87.1%. While diploid fish had greater body weights than those in the heat-shock treatment group, weight gain (WG%) was not different between the fry of the diploid and heat-shock treatment groups. Of thyroid hormones measured, 3,5,3'-triiodo-l-thyronine (T3) was less (P<0.05) in eyed eggs of the heat-shock treatment group, but thyroxine (T4) was greater in fry of the heat-shock treatment group as compared to those that were diploid. Cortisol concentration was greater in fry of the heat-shock treatment group as compared to those that were diploid suggesting that fry in the triploid state may be more susceptible to stressors. Concentrations of immune variables (lysozyme, ACH50, albumin, IgM, total protein, globulin and complement) were either comparable or greater in fry of the heat-shock treatment group suggesting that the immune

  3. Characteristics of alveolar bone associated with physiological movement of molar in mice: a histological and histochemical study.

    PubMed

    Matsuda, Kie; Haga-Tsujimura, Maiko; Yoshie, Sumio; Shimomura-Kuroki, Junko

    2014-01-01

    Mouse molars undergo distal movement, during which new bone is formed at the mesial side of the tooth root whereas the preexisting bone is resorbed at the distal side of the root. However, there is little detailed information available regarding which of the bones that surround the tooth root are involved in physiological tooth movement. In the present study, we therefore aimed to investigate the precise morphological differences of the alveolar bone between the bone formation side of the tooth root, using routine histological procedures including silver impregnation, as well as by immunohistochemical analysis of alkaline phosphatase and tartrate-resistant acid phosphatase activity, and immunohistochemical analysis of the expression of the osteocyte markers dentin matrix protein 1, sclerostin, and fibroblast growth factor 23. Histochemical analysis indicated that bone formation by osteoblasts and bone resorption by osteoclasts occurred at the bone formation side and the bone resorption side, respectively. Osteocyte marker immunoreactivity of osteocytes at the surface of the bone close to the periodontal ligament differed at the bone formation and bone resorption sides. We also showed different specific features of osteocytic lacunar canalicular systems at the bone formation and bone resorption sides by using silver staining. This study suggests that the alveolar bone is different in the osteocyte nature between the bone formation side and the bone resorption side due to physiological distal movement of the mouse molar.

  4. Characteristics of dissolved carbon change in irrigation water

    NASA Astrophysics Data System (ADS)

    Akaike, Y.; Kunishio, A.; Kawamoto, Y.; Murakami, H.; Iwata, T.

    2012-12-01

    It is necessary to estimate carbon emission from soil for understanding carbon cycle processes in cultivated fields. Since irrigation water is introduced into a typical rice paddy field, one part of emitted carbon content from soil were trapped by water and dissolved in it, and dissolved carbon content outflows from the field at the drainage moment. In this study, we continuously and regularly analyzed dissolved carbon content of irrigation water and investigated seasonal variation of efflux of carbon from a paddy field. Experimental site is located reclaimed land in the southern part of Okayama Prefecture, Japan. And rice cropping cultivation has continued in a similar method every year. Intermittent irrigation water managements, or 3 days flooded and 4 days drained condition, were carried out during almost all the period of rice cultivated term. Irrigation water was sampled every flooding and drainage days. Inorganic carbon (IC) concentration was measured with total carbon (TC) analyzer (TOC-V/CSH, SHIMAZU). Amount of dissolved carbon in irrigation water was calculated from product of the carbon concentration and water levels. The experimental paddy field was divided into two areas, and two bottle of water were sampled from each area. In order to investigate what impact is brought on the annual carbon cycle by the difference of disposal management of residual biomass after the harvest, residual biomass was burned and plowed into soil at the one area on 29th Nov., 2011, and residue was not burned and directly plowed into soil at the other area as usual. IC during cultivated term in 2011 and 2012 in both area gradually increased day by day for every flooded periods. And IC showed distinct diurnal variations with lower value in the daytime than at night, it is because of photosynthetic activities by aquatic algae in the irrigation water.

  5. Dynamic voltage-current characteristics for a water jet plasma arc

    SciTech Connect

    Yang Jiaxiang; Lan Sheng; Xu Zuoming

    2008-05-05

    A virtual instrument technology is used to measure arc current, arc voltage, dynamic V-I characteristics, and nonlinear conductance for a cone-shaped water jet plasma arc under ac voltage. Experimental results show that ac arc discharge mainly happens in water vapor evaporated from water when heated. However, due to water's cooling effect and its conductance, arc conductance, reignition voltage, extinguish voltage, and current zero time are very different from those for ac arc discharge in gas work fluid. These can be valuable to further studies on mechanism and characteristics of plasma ac discharge in water, and even in gas work fluid.

  6. OCCURRENCE OF HETEROTROPHIC BACTERIA WITH VIRULENCE CHARACTERISTICS IN POTABLE WATER

    EPA Science Inventory

    Treated potable water contains a variety of heterotrophic bacteria that survive current treatment processes. There is evidence that these bacteria are not hazardous to the healthy population, however, the possibility exists that some of them may be opportunistic pathogens capabl...

  7. VIRULENCE CHARACTERISTICS OF HETEROTROPHIC BACTERIA COMMONLY ISOLATED FROM POTABLE WATER

    EPA Science Inventory

    Heterotrophic bacteria isolated from drinking water distribution systems were examined to determine if they possessed putative virulence factors such as hemolysins, proteases, or cytotoxins. Representative samples of colonies from several different distribution systems indicated ...

  8. Physiological and Metagenomic Analyses of Microbial Mats Involved in Self-Purification of Mine Waters Contaminated with Heavy Metals

    PubMed Central

    Drewniak, Lukasz; Krawczyk, Pawel S.; Mielnicki, Sebastian; Adamska, Dorota; Sobczak, Adam; Lipinski, Leszek; Burec-Drewniak, Weronika; Sklodowska, Aleksandra

    2016-01-01

    Two microbial mats found inside two old (gold and uranium) mines in Zloty Stok and Kowary located in SW Poland seem to form a natural barrier that traps heavy metals leaking from dewatering systems. We performed complex physiological and metagenomic analyses to determine which microorganisms are the main driving agents responsible for self-purification of the mine waters and identify metabolic processes responsible for the observed features. SEM and energy dispersive X-ray microanalysis showed accumulation of heavy metals on the mat surface, whereas, sorption experiments showed that neither microbial mats were completely saturated with heavy metals present in the mine waters, indicating that they have a large potential to absorb significant quantities of metal. The metagenomic analysis revealed that Methylococcaceae and Methylophilaceae families were the most abundant in both communities, moreover, it strongly suggest that backbones of both mats were formed by filamentous bacteria, such as Leptothrix, Thiothrix, and Beggiatoa. The Kowary bacterial community was enriched with the Helicobacteraceae family, whereas the Zloty Stok community consist mainly of Sphingomonadaceae, Rhodobacteraceae, and Caulobacteraceae families. Functional (culture-based) and metagenome (sequence-based) analyses showed that bacteria involved in immobilization of heavy metals, rather than those engaged in mobilization, were the main driving force within the analyzed communities. In turn, a comparison of functional genes revealed that the biofilm formation and heavy metal resistance (HMR) functions are more desirable in microorganisms engaged in water purification than the ability to utilize heavy metals in the respiratory process (oxidation-reduction). These findings provide insight on the activity of bacteria leading, from biofilm formation to self-purification, of mine waters contaminated with heavy metals. PMID:27559332

  9. The fate of glyphosate in water hyacinth and its physiological and biochemical influences on growth of algae

    SciTech Connect

    Tsai, Baolong.

    1989-01-01

    Absorption, translocation, distribution, exudation, and guttation of {sup 14}C-glyphosate in water hyacinth (Eichhornia crassipes) were studied. Glyphosphate entered the plant by foliage and solution treatment. Plants were harvested and separated into the following parts: treated leaf blade, treated leaf petiole, young leaf blade, young leaf petiole, old leak blade, old leaf petiole, and root. Each part was extracted with methanol. Treated leaves, which exist only in foliage treatment, were washed with water and chloroform to remove the glyphosate residues. All {sup 14}C counting was made by liquid scintillation spectrometry. Autoradiography was used to locate {sup 14}C-glyphosate after foliage treatment. Results indicated that glyphosate can be absorbed from the leaf surface and translocated rapidly through phloem tissues into the whole plant body. The roots of water hyacinth absorbed glyphosate without vertical transport. Guttation of glyphosate occurred in treated leaf tips. Exudation of glyphosate from roots of water hyacinth occurred within 8 hr after foliage treatment. Chlorella vulgaris, Chlamydomonas reihardii, Anabaena cylindrica, and Chroococcus turgidus were used to explore the physiological and biochemical effects of glyphosate on algae. Spectrophotometric assays were performed for algal growth, chlorophyll, carotenoids, phycobiliprotein, carbohydrate, and protein. TLC procedures and an image analyzer were used to detect the metabolites of glyphosate inside algal cells. The common visible symptom of glyphosate toxicity in all algal cells were bleaching effect and reduction of contents of carbohydrate, protein, and pigments. The results highly suggested that glyphosate injured the algal cells by destruction of photosynthetic pigments and resulted in lowering the contents of carbohydrate and protein in algal cells.

  10. Physiological and Metagenomic Analyses of Microbial Mats Involved in Self-Purification of Mine Waters Contaminated with Heavy Metals.

    PubMed

    Drewniak, Lukasz; Krawczyk, Pawel S; Mielnicki, Sebastian; Adamska, Dorota; Sobczak, Adam; Lipinski, Leszek; Burec-Drewniak, Weronika; Sklodowska, Aleksandra

    2016-01-01

    Two microbial mats found inside two old (gold and uranium) mines in Zloty Stok and Kowary located in SW Poland seem to form a natural barrier that traps heavy metals leaking from dewatering systems. We performed complex physiological and metagenomic analyses to determine which microorganisms are the main driving agents responsible for self-purification of the mine waters and identify metabolic processes responsible for the observed features. SEM and energy dispersive X-ray microanalysis showed accumulation of heavy metals on the mat surface, whereas, sorption experiments showed that neither microbial mats were completely saturated with heavy metals present in the mine waters, indicating that they have a large potential to absorb significant quantities of metal. The metagenomic analysis revealed that Methylococcaceae and Methylophilaceae families were the most abundant in both communities, moreover, it strongly suggest that backbones of both mats were formed by filamentous bacteria, such as Leptothrix, Thiothrix, and Beggiatoa. The Kowary bacterial community was enriched with the Helicobacteraceae family, whereas the Zloty Stok community consist mainly of Sphingomonadaceae, Rhodobacteraceae, and Caulobacteraceae families. Functional (culture-based) and metagenome (sequence-based) analyses showed that bacteria involved in immobilization of heavy metals, rather than those engaged in mobilization, were the main driving force within the analyzed communities. In turn, a comparison of functional genes revealed that the biofilm formation and heavy metal resistance (HMR) functions are more desirable in microorganisms engaged in water purification than the ability to utilize heavy metals in the respiratory process (oxidation-reduction). These findings provide insight on the activity of bacteria leading, from biofilm formation to self-purification, of mine waters contaminated with heavy metals. PMID:27559332

  11. Physiological and behavioral basis for the successful adaptation of goats to severe water restriction under hot environmental conditions.

    PubMed

    Kaliber, M; Koluman, N; Silanikove, N

    2016-01-01

    Among domestic ruminants, goats are renowned for their ability to tolerate water deprivation, water restriction and energy restriction. However, some basic questions regarding their ability to endure water restriction under heat stress are still open. Three levels of water restriction (56%, 73% and 87% of the ad libitum) were imposed on 20 cross-bred 3-year-old female goats (75% German Fawn and 25% Hair Goat) distributed into four groups, with five animals per treatment. The experiment was conducted from the beginning of July to the end of August in a farm located in the Eastern Mediterranean region of Turkey (40 m in altitude; 36 59' N, 35 18'E), in which subtropical weather conditions prevail. The average daily temperature during the experiment was 34.2°C, whereas the highest and lowest temperatures were 42°C and 23.1°C, respectively. The average relative humidity was 68.2% and wind speed was 1.2 km/h. Weekly average thermal heat indexes during the experiment were 78.3 (week 1), 79.1 (week 2), 80.1 (weak 3), 79.8 (weak 4), 81.3 (weak 5) and on average 79.7. Feed intake, heart rate, thermoregulatory responses (rectal temperature, respiration rate), blood plasma concentrations of ions (Na, K), antidiuretic hormone (ADH), metabolites (glucose, cholesterol, creatinine and urea) and behavioral aspects (standing, walking, lying) were studied over 30 days. The responses to water restriction were proportional to the level of restriction. The reductions in feed intake (up to 13%), BW (up to 4.6%) and the increases in rectal temperature (0.5°C) and breath rate (10 respirations/min) were moderate and also were far from responses encountered under severe heat and water stresses. The increase in plasma Na (from 119 to 140 mM) and ADH concentrations (from 12.6 to 17.4 pg/ml) indicates that the physiological response to water restriction was in response to mild dehydration, which also explains the increase in blood plasma concentrations of glucose, cholesterol, creatinine

  12. Water Quality Characteristics of Sembrong Dam Reservoir, Johor, Malaysia

    NASA Astrophysics Data System (ADS)

    Mohd-Asharuddin, S.; Zayadi, N.; Rasit, W.; Othman, N.

    2016-07-01

    A study of water quality and heavy metal content in Sembrong Dam water was conducted from April - August 2015. A total of 12 water quality parameters and 6 heavy metals were measured and classified based on the Interim National Water Quality Standard of Malaysia (INWQS). The measured and analyzed parameter variables were divided into three main categories which include physical, chemical and heavy metal contents. Physical and chemical parameter variables were temperature, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), turbidity, pH, nitrate, phosphate, ammonium, conductivity and salinity. The heavy metals measured were copper (Cu), lead (Pb), aluminium (Al), chromium (Cr), ferum (Fe) and zinc (Zn). According to INWQS, the water salinity, conductivity, BOD, TSS and nitrate level fall under Class I, while the Ph, DO and turbidity lie under Class IIA. Furthermore, values of COD and ammonium were classified under Class III. The result also indicates that the Sembrong Dam water are not polluted with heavy metals since all heavy metal readings recorded were falls far below Class I.

  13. Genomic, physiologic, and proteomic insights into metabolic versatility in Roseobacter clade bacteria isolated from deep-sea water

    PubMed Central

    Tang, Kai; Yang, Yujie; Lin, Dan; Li, Shuhui; Zhou, Wenchu; Han, Yu; Liu, Keshao; Jiao, Nianzhi

    2016-01-01

    Roseobacter clade bacteria are ubiquitous in marine environments and now thought to be significant contributors to carbon and sulfur cycling. However, only a few strains of roseobacters have been isolated from the deep-sea water column and have not been thoroughly investigated. Here, we present the complete genomes of phylogentically closed related Thiobacimonas profunda JLT2016 and Pelagibaca abyssi JLT2014 isolated from deep-sea water of the Southeastern Pacific. The genome sequences showed that the two deep-sea roseobacters carry genes for versatile metabolisms with functional capabilities such as ribulose bisphosphate carboxylase-mediated carbon fixation and inorganic sulfur oxidation. Physiological and biochemical analysis showed that T. profunda JLT2016 was capable of autotrophy, heterotrophy, and mixotrophy accompanied by the production of exopolysaccharide. Heterotrophic carbon fixation via anaplerotic reactions contributed minimally to bacterial biomass. Comparative proteomics experiments showed a significantly up-regulated carbon fixation and inorganic sulfur oxidation associated proteins under chemolithotrophic conditions compared to heterotrophic conditions. Collectively, rosebacters show a high metabolic flexibility, suggesting a considerable capacity for adaptation to the marine environment. PMID:27762339

  14. Rapid toxicity screening of sediment pore waters using physiological and biochemical biomarkers of Daphnia magna

    SciTech Connect

    Coen, W.M. De; Janssen, C.R.; Persoone, G.

    1995-12-31

    Two new rapid toxicity tests, based on ingestion activity and digestive enzyme activity of D. magna, were developed and evaluated. The ingestion activity was measured using fluorescent latex micro-beads and an automated microplate fluorimeter allowing a sensitive quantification of the feeding activity of the organisms. The activity of the digestive enzymes, 6-galactosidase, esterase and trypsin, was determined in test organism homogenates using the following fluorogenic{sup 1} and chromogenic{sup 2} substrates: 4-methylumbelliferyl-{beta}-D galactoside{sup 1}, fluorescin diacetate{sup 1} and N-Benzoyl-L-arginine-4-nitroanilide{sup 2}. Both biomarker techniques were developed to allow rapid toxicity screening on a routine basis. The toxicity of the pore waters of eight contaminated samples was assessed with the aid of the developed biomarker assays. Comparison of the conventional 24h EC50 values with the EC50 values obtained with the 1.5h ingestion test and the threshold concentrations of the 2h digestive enzyme tests revealed a positive correlation between the different effect concentrations. A similar correlation (r{sup 2} = 0.87) between the conventional 24h EC50 values and 1.5h EC50 values was observed in toxicity tests with pure compounds. Correlation coefficients for the relationships between the 3 enzyme effect concentrations and the 24h EC50 values ranged from 0.95 to 0.98, The positive correlations between the conventional and biomarker effect criteria, observed for both environmental samples and pure compounds, demonstrate the potential use of the developed methods as rapid toxicity screening tools.

  15. Design of a Water Soluble Fluorescent 3-Hydroxy-4-Pyridinone Ligand Active at Physiological pH Values.

    PubMed

    Leite, Andreia; Silva, Ana M G; Coutinho, Catarina; Cunha-Silva, Luís; de Castro, Baltazar; Rangel, Maria

    2016-09-01

    In the present work we report the structure and the spectroscopic characterization of a new fluorescent 3-hydroxy-4-pyridinone ligand D-3,4-HPO. The synthesis of the compound was performed in two steps, which involve the reaction of the commercially available fluorophore dansyl chloride with a 3-hydroxy-4-pyridinone chelating unit and further deprotection. The new fluorescent chelator was characterized in the solid state by single-crystal X-ray diffraction and in solution by NMR, MS, absorption and fluorescence spectroscopies. The analysis of the variation of the absorption spectrum with pH allowed the determination of four pK a values (pK a1  = 3.50, pK a2  = 4.50, pK a3  = 9.60, pK a4  = 10.20) and establishment of the corresponding distribution diagram. The study of the fluorescence properties of the ligand show that in the pH range between 4 and 9 the fluorescence intensity is constant and has its maximum value thus allowing its further use at physiological pH values. The interaction of the ligand with copper(II) was accessed by fluorescence spectroscopy in MOPS buffer and the results show that the presence of copper(II) quenches the fluorescence of the ligand in ca 94 % at a ligand: metal ratio of 2:1. The latter result is consistent with the formation of a copper(II) complex with the bidentate ligand, as confirmed by the EPR spectroscopy. Graphical Abstract New water soluble fluorescent ligand active at physiological pH values. PMID:27357392

  16. Design of a Water Soluble Fluorescent 3-Hydroxy-4-Pyridinone Ligand Active at Physiological pH Values.

    PubMed

    Leite, Andreia; Silva, Ana M G; Coutinho, Catarina; Cunha-Silva, Luís; de Castro, Baltazar; Rangel, Maria

    2016-09-01

    In the present work we report the structure and the spectroscopic characterization of a new fluorescent 3-hydroxy-4-pyridinone ligand D-3,4-HPO. The synthesis of the compound was performed in two steps, which involve the reaction of the commercially available fluorophore dansyl chloride with a 3-hydroxy-4-pyridinone chelating unit and further deprotection. The new fluorescent chelator was characterized in the solid state by single-crystal X-ray diffraction and in solution by NMR, MS, absorption and fluorescence spectroscopies. The analysis of the variation of the absorption spectrum with pH allowed the determination of four pK a values (pK a1  = 3.50, pK a2  = 4.50, pK a3  = 9.60, pK a4  = 10.20) and establishment of the corresponding distribution diagram. The study of the fluorescence properties of the ligand show that in the pH range between 4 and 9 the fluorescence intensity is constant and has its maximum value thus allowing its further use at physiological pH values. The interaction of the ligand with copper(II) was accessed by fluorescence spectroscopy in MOPS buffer and the results show that the presence of copper(II) quenches the fluorescence of the ligand in ca 94 % at a ligand: metal ratio of 2:1. The latter result is consistent with the formation of a copper(II) complex with the bidentate ligand, as confirmed by the EPR spectroscopy. Graphical Abstract New water soluble fluorescent ligand active at physiological pH values.

  17. Modelling Soil Water Characteristic Curves for the Investigation of Hydrophobicity

    NASA Astrophysics Data System (ADS)

    Hallin, Ingrid; Matthews, Peter; Laudone, Maurizio; Van Keulen, Geertje; Doerr, Stefan; Francis, Lewis; Dudley, Ed; Gazze, Andrea; Quinn, Gerry; Whalley, Richard; Ashton, Rhys

    2016-04-01

    Soil hydrophobicity presents a major challenge for the future, as it reduces both plant-available water and irrigation efficiency, and can increase flooding hazards and erosion. A collaborative research project has been set up in the UK to study hydrophobicity over a wide range of length scales. At core scale, we are investigating the wetting behaviour of water repellent soils in order to model percolation through hydrophobic pore spaces. To that end, water retention measurements were carried out on both wettable and forcibly-wetted water-repellent soils collected from three locations in England and Wales. The data were then fitted with both the commonly used Van Genuchten model and an alternative model from PoreXpert, a software program that analyses and models porous materials. The Van Genuchten model fits a curve to the data using parameters related to air entry suction, irreducible water content and pore size distribution. By contrast, PoreXpert uses a Boltzmann-annealed simplex to find a best-fit curve based on parameters directly related to the void structure of the soil: the size of the voids, the shape of the void size distribution, and how the voids are connected to each other. Both Van Genuchten and PoreXpert fit the experimental data well, but where Van Genuchten forces an S-shaped curve that can mask small variations, PoreXpert gives a closer fit of no pre-defined shape that captures subtle differences between data points. This allows us to calculate differences in the effective pore and throat size distributions, and provides a mechanistic framework from which to model additional hydrologic behaviour in water repellent soil. Simulations of capillary induced wetting based on these mechanistic postulates are then compared to wicking experiments at the core scale, which can then be upscaled and applied to other soils.

  18. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    PubMed

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane. PMID:26387296

  19. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].

    PubMed

    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming

    2015-06-01

    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane.

  20. Partitioning characteristics of perfluorooctane sulfonate between water and foods.

    PubMed

    Xiao, Feng; Simcik, Matt F; Gulliver, John S

    2012-01-01

    As a persistent, bioaccumulative, and toxic organic pollutant, perfluorooctane sulfonate (PFOS) has been found ubiquitously in the environment, including in tap water. For the first time, we studied PFOS sorption from water to foods (nine commonly consumed vegetables, three meats, and cereals) at two temperatures to estimate the daily intake of PFOS attributable to cooking and food preparation. The values of the food water-distribution coefficient (KF/W, l/kg) of PFOS ranged from 7 to 19 l/kg for most vegetables and from 19 to 38 l/kg for meats. Celery exhibited the highest affinity toward PFOS (KF/W=39.8±3.4 l/kg), whereas onions showed the lowest affinity toward PFOS (KF/W=1.1±0.4 l/kg). Adding table salt (sodium chloride) greatly increased PFOS sorption in most foods, except for celery and meats. The results indicate that human exposure to PFOS could result from the sorption of PFOS from water to food during food preparation, especially when using table salt. The average daily intake of PFOS through this route was estimated. Furthermore, raw and unprocessed foods (vegetables, meats, and cereals) bought from farmers' markets and grocery stores were basically free of PFOS and other long-chain perfluoroalkyl acids.

  1. Partitioning characteristics of perfluorooctane sulfonate between water and foods.

    PubMed

    Xiao, Feng; Simcik, Matt F; Gulliver, John S

    2012-01-01

    As a persistent, bioaccumulative, and toxic organic pollutant, perfluorooctane sulfonate (PFOS) has been found ubiquitously in the environment, including in tap water. For the first time, we studied PFOS sorption from water to foods (nine commonly consumed vegetables, three meats, and cereals) at two temperatures to estimate the daily intake of PFOS attributable to cooking and food preparation. The values of the food water-distribution coefficient (KF/W, l/kg) of PFOS ranged from 7 to 19 l/kg for most vegetables and from 19 to 38 l/kg for meats. Celery exhibited the highest affinity toward PFOS (KF/W=39.8±3.4 l/kg), whereas onions showed the lowest affinity toward PFOS (KF/W=1.1±0.4 l/kg). Adding table salt (sodium chloride) greatly increased PFOS sorption in most foods, except for celery and meats. The results indicate that human exposure to PFOS could result from the sorption of PFOS from water to food during food preparation, especially when using table salt. The average daily intake of PFOS through this route was estimated. Furthermore, raw and unprocessed foods (vegetables, meats, and cereals) bought from farmers' markets and grocery stores were basically free of PFOS and other long-chain perfluoroalkyl acids. PMID:21597984

  2. Performance-related characteristics of water reactor fuel

    NASA Astrophysics Data System (ADS)

    Bairiot, H.; Vanderborck, Y.; Dumbruch, G.

    1982-04-01

    The most widely utilized manufacturing routes are based on different conversion processes: precipitation from aqueous solutions ("wet processes") and dry processes. The characteristics of the resulting powders (grain size, flowability, etc…) influence the pellet fabrication steps and even the sintered pellet characteristics. Depending on the powder characteristics, the pelletizing can be done directly or requires a previous conditioning. This preconditioning may include blending additives for further processing, for modifying the final pellet structure or for incorporating fissile or poison material. Controls at this stage are usually limited to homogeneity of the dispersion of additives. The sintering process parameters are monitored to insure that the pellet structure presents adequate densification stability. As a final product, the pellet is also subjected to all the controls required to demonstrate that the specifications are met. The paper reviews the controls applied for what regards the major components, the structural features and the geometry. Rather than the presentation of control techniques, the paper discusses the subject in the light of methods and procedures, typically applied in todays industrial fabrication.

  3. Optical characteristics of natural waters protect amphibians from UV-B in the U.S. Pacific Northwest

    USGS Publications Warehouse

    Palen, Wendy J.; Schindler, David E.; Adams, Michael J.; Pearl, Christopher A.; Bury, R. Bruce; Diamond, S.A.

    2002-01-01

    Increased exposure to ultraviolet-B (UV-B) radiation has been proposed as a major environmental stressor leading to global amphibian declines. Prior experimental evidence from the U.S. Pacific Northwest (PNW) indicating the acute embryonic sensitivity of at least four amphibian species to UV-B has been central to the literature about amphibian decline. However, these results have not been expanded to address population-scale effects and natural landscape variation in UV-B transparency of water at amphibian breeding sites: both necessary links to assess the importance of UV-B for amphibian declines. We quantified the UV-B transparency of 136 potential amphibian breeding sites to establish the pattern of UV-B exposure across two montane regions in the PNW. Our data suggest that 85% of sites are naturally protected by dissolved organic matter in pond water, and that only a fraction of breeding sites are expected to experience UV-B intensities exceeding levels associated with elevated egg mortality. Thus, the spectral characteristics of natural waters likely mediate the physiological effects of UV-B on amphibian eggs in all but the clearest waters. These data imply that UV-B is unlikely to cause broad amphibian declines across the landscape of the American Northwest.

  4. Psychological and physiological characteristics of a proposed object-referral/self-referral continuum of self-awareness.

    PubMed

    Travis, Frederick; Arenander, Alarik; DuBois, David

    2004-06-01

    This research extends and confirms recent brainwave findings that distinguished an individual's sense-of-self along an Object-referral/Self-referral Continuum of self-awareness. Subjects were interviewed and were given tests measuring inner/outer orientation, moral reasoning, anxiety, and personality. Scores on the psychological tests were factor analyzed. The first unrotated PCA component of the test scores yielded a "Consciousness Factor," analogous to the intelligence "g" factor, which accounted for over half of the variance among groups. Analysis of unstructured interviews of these subjects revealed fundamentally different descriptions of self-awareness. Individuals who described themselves in terms of concrete cognitive and behavioral processes (predominantly Object-referral mode) exhibited lower Consciousness Factor scores, lower frontal EEG coherence, lower alpha and higher gamma power during tasks, and less efficient cortical preparatory responses (contingent negative variation). In contrast, individuals who described themselves in terms of an abstract, independent sense-of-self underlying thought, feeling and action (predominantly Self-referral mode) exhibited higher Consciousness Factor scores, higher frontal coherence, higher alpha and lower gamma power during tasks, and more efficient cortical responses. These data suggest that definable states of brain activity and subjective experiences exist, in addition to waking, sleeping and dreaming, that may be operationally defined by psychological and physiological measures along a continuum of Object-referral/Self-referral Continuum of self-awareness.

  5. Differential Gene Expression Reflects Morphological Characteristics and Physiological Processes in Rice Immunity against Blast Pathogen Magnaporthe oryzae.

    PubMed

    Azizi, Parisa; Rafii, Mohd Y; Mahmood, Maziah; Abdullah, Siti N A; Hanafi, Mohamed M; Nejat, Naghmeh; Latif, Muhammad A; Sahebi, Mahbod

    2015-01-01

    The rice blast fungus Magnaporthe oryzae is a serious pathogen that jeopardises the world's most important food-security crop. Ten common Malaysian rice varieties were examined for their morphological, physiological and genomic responses to this rice blast pathogen. qPCR quantification was used to assess the growth of the pathogen population in resistant and susceptible rice varieties. The chlorophyll content and photosynthesis were also measured to further understand the disruptive effects that M. oryzae has on infected plants of these varieties. Real-time PCR was used to explore the differential expression of eight blast resistance genes among the ten local varieties. Blast disease has destructive effects on the growth of rice, and the findings of our study provide evidence that the Pikh, Pi9, Pi21, and Osw45 genes are involved in defence responses in the leaves of Malaysian rice at 31 h after inoculation with M. oryzae pathotype P7.2. Both the chlorophyll content and photosynthesis were reduced, but the levels of Pikh gene expression remained constant in susceptible varieties, with a developed pathogen population and mild or severe symptoms. The Pi9, Pi21, and Osw45 genes, however, were simultaneously upregulated in infected rice plants. Therefore, the presence of the Pikh, Pi9, Pi21, and Osw45 genes in the germplasm is useful for improving the resistance of rice varieties. PMID:26001124

  6. Differential Gene Expression Reflects Morphological Characteristics and Physiological Processes in Rice Immunity against Blast Pathogen Magnaporthe oryzae

    PubMed Central

    Mahmood, Maziah; Abdullah, Siti N. A.; Hanafi, Mohamed M.; Nejat, Naghmeh; Latif, Muhammad A.

    2015-01-01

    The rice blast fungus Magnaporthe oryzae is a serious pathogen that jeopardises the world’s most important food-security crop. Ten common Malaysian rice varieties were examined for their morphological, physiological and genomic responses to this rice blast pathogen. qPCR quantification was used to assess the growth of the pathogen population in resistant and susceptible rice varieties. The chlorophyll content and photosynthesis were also measured to further understand the disruptive effects that M. oryzae has on infected plants of these varieties. Real-time PCR was used to explore the differential expression of eight blast resistance genes among the ten local varieties. Blast disease has destructive effects on the growth of rice, and the findings of our study provide evidence that the Pikh, Pi9, Pi21, and Osw45 genes are involved in defence responses in the leaves of Malaysian rice at 31 h after inoculation with M. oryzae pathotype P7.2. Both the chlorophyll content and photosynthesis were reduced, but the levels of Pikh gene expression remained constant in susceptible varieties, with a developed pathogen population and mild or severe symptoms. The Pi9, Pi21, and Osw45 genes, however, were simultaneously upregulated in infected rice plants. Therefore, the presence of the Pikh, Pi9, Pi21, and Osw45 genes in the germplasm is useful for improving the resistance of rice varieties. PMID:26001124

  7. Effect of sweet wormwood Artemisia annua crude leaf extracts on some biological and physiological characteristics of the lesser mulberry pyralid, Glyphodes pyloalis.

    PubMed

    Khosravi, Roya; Sendi, Jalal Jalali; Ghadamyari, Mohammad; Yezdani, Elham

    2011-01-01

    The lesser mulberry pyralid, Glyphodes pyloalis Walker (Lepidoptera: Pyralidae) is a monophagous and dangerous pest of mulberry that has been recently observed in Guilan province, northern Iran. In this study, the crude methanol extract of sweet wormwood Artemisia annua L. (Asterales: Asteracaea) was investigated on toxicity, biological and physiological characteristics of this pest under controlled conditions (24 ± 1 °C, 75 ± 5% RH, and 16:8 L:D photoperiod). The effect of acute toxicity and sublethal doses on physiological characteristics was performed by topical application. The LC₅₀ and LC₂₀ values on fourth instar larvae were calculated as 0.33 and 0.22 gram leaf equivalent/ mL, respectively. The larval duration of fifth instar larvae in LC₅₀ treatment was prolonged (5.8 ± 0.52 days) compared with the control group (4.26 ± 0.29 days). However larval duration was reduced in the LC₂₀ treatment. The female adult longevity in the LC₅₀ dose was the least (4.53 ± 0.3 days), while longevity among controls was the highest (9.2 ± 0.29 days). The mean fecundity of adults after larval treatment with LC₅₀ was recorded as 105.6 ± 16.84 eggs/female, while the control was 392.74 ± 22.52 eggs/female. The percent hatchability was reduced in all treatments compared with the control. The effect of extract in 0.107, 0.053, 0.026 and 0.013 gle/mL on biochemical characteristics of this pest was also studied. The activity of α-amylase and protease 48 hours post-treatment was significantly reduced compared with the control. Similarly lipase, esterase, and glutathione S-transferase activity were significantly affected by A. annua extract.

  8. Moisture characteristics of water-repellent consolidants and their applicability to existing buildings

    NASA Astrophysics Data System (ADS)

    Iba, Chiemi; Fukui, Kazuma; Hokoi, Shuichi

    2016-07-01

    Water-repellent agents are considered an effective measure of preventing moisture damage in building materials. However, data on the moisture transfer characteristics of repellent materials are insufficient. This study focused on the transfer of liquid water in a porous building material and quantitatively evaluated the applicability of a water-repellent consolidant as a protection agent via water infiltration experiments and numerical analysis. The experimental results could be reproduced by treating the water-repellent consolidant as having two layers with different water conductivities.

  9. Genotypic Variation in Growth and Physiological Response to Drought Stress and Re-Watering Reveals the Critical Role of Recovery in Drought Adaptation in Maize Seedlings.

    PubMed

    Chen, Daoqian; Wang, Shiwen; Cao, Beibei; Cao, Dan; Leng, Guohui; Li, Hongbing; Yin, Lina; Shan, Lun; Deng, Xiping

    2015-01-01

    Non-irrigated crops in temperate climates and irrigated crops in arid climates are subjected to continuous cycles of water stress and re-watering. Thus, fast and efficient recovery from water stress may be among the key determinants of plant drought adaptation. The present study was designed to comparatively analyze the roles of drought resistance and drought recovery in drought adaptation and to investigate the physiological basis of genotypic variation in drought adaptation in maize (Zea mays) seedlings. As the seedlings behavior in growth associate with yield under drought, it could partly reflect the potential of drought adaptability. Growth and physiological responses to progressive drought stress and recovery were observed in seedlings of 10 maize lines. The results showed that drought adaptability is closely related to drought recovery (r = 0.714(**)), but not to drought resistance (r = 0.332). Drought induced decreases in leaf water content, water potential, osmotic potential, gas exchange parameters, chlorophyll content, Fv/Fm and nitrogen content, and increased H2O2 accumulation and lipid peroxidation. After recovery, most of these physiological parameters rapidly returned to normal levels. The physiological responses varied between lines. Further correlation analysis indicated that the physiological bases of drought resistance and drought recovery are definitely different, and that maintaining higher chlorophyll content (r = 0.874(***)) and Fv/Fm (r = 0.626(*)) under drought stress contributes to drought recovery. Our results suggest that both drought resistance and recovery are key determinants of plant drought adaptation, and that drought recovery may play a more important role than previously thought. In addition, leaf water potential, chlorophyll content and Fv/Fm could be used as efficient reference indicators in the selection of drought-adaptive genotypes. PMID:26793218

  10. Genotypic Variation in Growth and Physiological Response to Drought Stress and Re-Watering Reveals the Critical Role of Recovery in Drought Adaptation in Maize Seedlings

    PubMed Central

    Chen, Daoqian; Wang, Shiwen; Cao, Beibei; Cao, Dan; Leng, Guohui; Li, Hongbing; Yin, Lina; Shan, Lun; Deng, Xiping

    2016-01-01

    Non-irrigated crops in temperate climates and irrigated crops in arid climates are subjected to continuous cycles of water stress and re-watering. Thus, fast and efficient recovery from water stress may be among the key determinants of plant drought adaptation. The present study was designed to comparatively analyze the roles of drought resistance and drought recovery in drought adaptation and to investigate the physiological basis of genotypic variation in drought adaptation in maize (Zea mays) seedlings. As the seedlings behavior in growth associate with yield under drought, it could partly reflect the potential of drought adaptability. Growth and physiological responses to progressive drought stress and recovery were observed in seedlings of 10 maize lines. The results showed that drought adaptability is closely related to drought recovery (r = 0.714**), but not to drought resistance (r = 0.332). Drought induced decreases in leaf water content, water potential, osmotic potential, gas exchange parameters, chlorophyll content, Fv/Fm and nitrogen content, and increased H2O2 accumulation and lipid peroxidation. After recovery, most of these physiological parameters rapidly returned to normal levels. The physiological responses varied between lines. Further correlation analysis indicated that the physiological bases of drought resistance and drought recovery are definitely different, and that maintaining higher chlorophyll content (r = 0.874***) and Fv/Fm (r = 0.626*) under drought stress contributes to drought recovery. Our results suggest that both drought resistance and recovery are key determinants of plant drought adaptation, and that drought recovery may play a more important role than previously thought. In addition, leaf water potential, chlorophyll content and Fv/Fm could be used as efficient reference indicators in the selection of drought-adaptive genotypes. PMID:26793218

  11. The influence of supply and sewerage area characteristics on water and sewerage companies responses to the Water Framework Directive.

    PubMed

    Spiller, M; McIntosh, B S; Seaton, R A F

    2009-01-01

    Using the example of raw water quality this paper examines the relationship between different spatial characteristics (geographical and physical properties) of Water and Sewerage Companies (WaSCs) supply and sewage areas and response to the Water Framework Directive. Results were obtained from thematic analysis and content analysis of 14 interviews with WaSCs representatives. Principal component analysis and cluster analysis of 51 WaSCs business function characteristics was employed to derive groups of similar WaSCs. Results indicate that there is difference in how WaSCs approach raw water quality issues. It appears that small WaSCs with relatively large agricultural areas in their supply catchments are more likely to seek managerial solutions to raw water quality problems.

  12. MUTAGENIC CHARACTERISTICS OF RIVER WATERS FLOWING THROUGH LARGE METROPOLITAN AREAS IN NORTH AMERICA

    EPA Science Inventory

    Mutagenic characteristics of river waters flowing through large metropolitan areas in North America

    The hanging technique using blue rayon, which specifically adsorbs mutagens with multicyclic planar structures, has the advantages over most conventional methods of not havi...

  13. Investigating the influence of nitrate nitrogen on post-smolt Atlantic salmon Salmo salar reproductive physiology in water recirculation aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An 8-month trial was carried out to assess the effects of NO3-N on a variety of performance and physiological outcomes in post-smolt Atlantic salmon Salmo salar (initial weight 102 plus or minus 1 g) reared in six replicated laboratory-scale water recirculation aquaculture systems (RAS). Three RAS r...

  14. Water removal characteristics of proton exchange membrane fuel cells using a dry gas purging method

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Yeop; Kim, Sang-Uk; Kim, Hyoung-Juhn; Jang, Jong Hyun; Oh, In-Hwan; Cho, Eun Ae; Hong, Seong-Ahn; Ko, Jaejun; Lim, Tae-Won; Lee, Kwan-Young; Lim, Tae-Hoon

    Water removal from proton exchange membrane fuel cells (PEMFC) is of great importance to improve start-up ability and mitigate cell degradation when the fuel cell operates at subfreezing temperatures. In this study, we report water removal characteristics under various shut down conditions including a dry gas-purging step. In order to estimate the dehydration level of the electrolyte membrane, the high frequency resistance of the fuel cell stack was observed. Also, a novel method for measuring the amount of residual water in the fuel cell was developed to determine the amount of water removal. The method used the phase change of liquid water and was successfully applied to examine the water removal characteristics. Based on these works, the effects of several parameters such as purging time, flow rate of purging gas, operation current, and stack temperature on the amount of residual water were investigated.

  15. Nitrous oxide emission and mitigation from wheat agriculture: association of physiological and anatomical characteristics of wheat genotypes.

    PubMed

    Borah, Leena; Baruah, Kushal Kumar

    2016-01-01

    Agriculture is an important source of emission of the greenhouse gas nitrous oxide (N2O). The observed differences in N2O emission among different varieties of agricultural crops can be a key factor for developing N2O emission reduction strategies. N2O emissions were estimated from three varieties of wheat viz. Sonalika, DBW 39, and K 0307 during 2010-2011 in an attempt to identify plant physiological and anatomical factors contributing to differences in gas emissions within the varieties. Sonalika was identified as a low N2O emitting variety and DBW 39 as high emitting when grown in a uniform field condition. The experiment was repeated in 2011-2012 selecting low emitting Sonalika and high emitting variety DBW 39 for further confirmation of the results obtained during the first year of experimentation. Important plant factors namely rate of photosynthesis and transpiration in flag leaf, stomatal frequency of adaxial flag leaf surface, and size of the xylem vessels (mean vessel size of node, stem, and root) were studied, and their relationship with N2O flux was worked out. A good correlation between transpiration and N2O flux was observed in this study. Scanning electron microscopic investigation revealed strong association of flag leaf stomatal frequency and xylem size with N2O emission. Sonalika, identified as low N2O emitting variety during both the years of study, also recorded higher grain yield due to its higher efficiency of photosynthate allocation toward the developing grains. The observed differences in N2O emission are considered to be due largely to genetic differences in the wheat genotypes. PMID:26335526

  16. The impact of stress on motor performance in skilled musicians suffering from focal dystonia: Physiological and psychological characteristics.

    PubMed

    Ioannou, Christos I; Furuya, Shinichi; Altenmüller, Eckart

    2016-05-01

    Recent investigations have suggested that stress can modulate motor function. However, the impact of stress on motor performance of musicians suffering from focal dystonia (FDM) remains unknown. The current study assessed motor performance in 20 FDM patients and 16 healthy musicians (HM) before and under stress. Stress was manipulated using the Trier Social Stress Test (TSST). Motor performance was evaluated based on analysis of electromyographic (EMG) activity and temporal variability, while electrocardiography (ECG) and the level of free cortisol were used to test for objective alterations of the hypothalamic-pituitary-adrenal (HPA) axis. Finally, the psychological profiles of both groups were analyzed using three psycho-diagnostic standardized questionnaires. Results showed that patients' motor impairments did not change under acute stressful conditions. However, an increase in muscular co-contractions was observed, reflecting a physiological muscular response under stressful conditions. Psycho-diagnostic analysis revealed higher levels of psychological traits related to elevated anxiety, stress and perfectionism in 40% of the patients. Although the motor outcome between those patients and those with an opposing psychological profile did not differ, patients characterized by stressful and perfectionistic personalities had, on average, developed dystonia about ten years earlier than the rest of the patients. The current study suggests that acute stress conditions may not have any direct impact on fine motor control of FDM patients. However psychological traits associated with increased stress, anxiety and perfectionism may have a long-lasting effect on the motor function of affected musicians, by promoting the acceleration or even the triggering of dystonia. PMID:27033741

  17. Biofouling characteristics and identification of preponderant bacteria at different nutrient levels in batch tests of a recirculating cooling water system.

    PubMed

    Liu, Fang; Zhao, Chao-Cheng; Xia, Lu; Yang, Fei; Chang, Xin; Wang, Yong-Qiang

    2011-01-01

    Understanding the influence of nutrient levels on biofouling control is an important requirement for management strategies in a recirculating cooling water system. Nutrient limitation may be one way to control biofouling development without increasing biocide dosing. Therefore, this study was carried out to investigate the effects of nutrient levels on biofouling characteristics and to identify the preponderant bacteria in the batch tests with a simulated cooling water system. The biofouling characteristics were assessed by varying the biofoulant mass and the bacteria respiratory activity, which was estimated by measuring oxygen uptake rates. According to the results obtained in nutrient factor experiments, the biofouling could be better controlled at carbon, nitrogen and phosphorus concentrations of 30 mg N/L, 8 mg N/L and 1.0 mg P/L, respectively. Increasing carbon concentrations shortened the biofouling initial growth period and resulted in higher biofoulant mass. The preponderant bacteria strains involved in biofouling under two culture conditions were identified by applying both physiological and biochemical tests and further molecular biology techniques with phylogenetic affiliation analysis. Enterobacter (family Enterobacteriaceae), Staphylococcus (family Micrococcaceae), Bacillus (family Bacillaceae), Proteus (family Enterobacteriaceae), Neisseria (family Neisseriaceae) and Pseudomonas (family Pseudomonadaceae) were dominant in the conditions of lower carbon concentration (30 mg/L). Enterobacter are autotrophs, but the other five bacteria are all heterotrophs. In the conditions of higher carbon concentration (70 mg/L), Klebsiella (family Enterobacteriaceae), Enterobacter and Microbacterium (family Microbacteriaceae) were dominant; Enterobacter and Microbacterium are heterotrophs.

  18. Mineralogical and geochemical characteristics of drinking water salt deposits

    NASA Astrophysics Data System (ADS)

    Soktoev, B. R.; Rikhvanov, L. P.; Matveenko, I. A.

    2015-11-01

    The article presents the research results on the features of element and mineral composition of salt deposits (limescale) formed in household conditions in heat exchanging equipment. The major part of limescale is represented by two species of calcium carbonate - calcite and aragonite. We have shown that high concentrations of chemical elements in the limescale promote the formation of their own mineral forms (sulphates, silicates, native forms) in salt deposits. Detecting such mineral formations suggests the salt deposits of drinking water to be a long-term storage media which can be used in the course of eco-geochemical and metallogenic studies.

  19. Genotype-environment interactions affecting preflowering physiological and morphological traits of Brassica rapa grown in two watering regimes.

    PubMed

    El-Soda, Mohamed; Boer, Martin P; Bagheri, Hedayat; Hanhart, Corrie J; Koornneef, Maarten; Aarts, Mark G M

    2014-02-01

    Plant growth and productivity are greatly affected by drought, which is likely to become more threatening with the predicted global temperature increase. Understanding the genetic architecture of complex quantitative traits and their interaction with water availability may lead to improved crop adaptation to a wide range of environments. Here, the genetic basis of 20 physiological and morphological traits is explored by describing plant performance and growth in a Brassica rapa recombinant inbred line (RIL) population grown on a sandy substrate supplemented with nutrient solution, under control and drought conditions. Altogether, 54 quantitative trait loci (QTL) were identified, of which many colocated in 11 QTL clusters. Seventeen QTL showed significant QTL-environment interaction (Q×E), indicating genetic variation for phenotypic plasticity. Of the measured traits, only hypocotyl length did not show significant genotype-environment interaction (G×E) in both environments in all experiments. Correlation analysis showed that, in the control environment, stomatal conductance was positively correlated with total leaf dry weight (DW) and aboveground DW, whereas in the drought environment, stomatal conductance showed a significant negative correlation with total leaf DW and aboveground DW. This correlation was explained by antagonistic fitness effects in the drought environment, controlled by a QTL cluster on chromosome A7. These results demonstrate that Q×E is an important component of the genetic variance and can play a great role in improving drought tolerance in future breeding programmes.

  20. A comparison of physiological and transcriptome responses to water deprivation and salt loading in the rat supraoptic nucleus

    PubMed Central

    Greenwood, Michael P.; Mecawi, Andre S.; Hoe, See Ziau; Mustafa, Mohd Rais; Johnson, Kory R.; Al-Mahmoud, Ghada A.; Elias, Lucila L. K.; Paton, Julian F. R.; Antunes-Rodrigues, Jose; Gainer, Harold; Murphy, David

    2015-01-01

    Salt loading (SL) and water deprivation (WD) are experimental challenges that are often used to study the osmotic circuitry of the brain. Central to this circuit is the supraoptic nucleus (SON) of the hypothalamus, which is responsible for the biosynthesis of the hormones, arginine vasopressin (AVP) and oxytocin (OXT), and their transport to terminals that reside in the posterior lobe of the pituitary. On osmotic challenge evoked by a change in blood volume or osmolality, the SON undergoes a function-related plasticity that creates an environment that allows for an appropriate hormone response. Here, we have described the impact of SL and WD compared with euhydrated (EU) controls in terms of drinking and eating behavior, body weight, and recorded physiological data including circulating hormone data and plasma and urine osmolality. We have also used microarrays to profile the transcriptome of the SON following SL and remined data from the SON that describes the transcriptome response to WD. From a list of 2,783 commonly regulated transcripts, we selected 20 genes for validation by qPCR. All of the 9 genes that have already been described as expressed or regulated in the SON by osmotic stimuli were confirmed in our models. Of the 11 novel genes, 5 were successfully validated while 6 were false discoveries. PMID:25632023

  1. Common and divergent physiological, hormonal and metabolic responses of Arabidopsis thaliana and Thellungiella halophila to water and salt stress.

    PubMed

    Arbona, Vicent; Argamasilla, Rosa; Gómez-Cadenas, Aurelio

    2010-11-01

    To explain the higher tolerance of Thellungiella to abiotic stress in comparison to Arabidopsis, several studies have focused on differences in ion absorption and gene expression. However, little is known about hormone regulation and metabolic responses. In this work, plants of both species were subjected to desiccation and salt stress to compare common and divergent responses. In control conditions, the number of significantly upregulated mass features as well as proline levels was higher in Tellungiella than in Arabidopsis. When subjected to desiccation, both species exhibited similar rates of water loss but proline over accumulation only occurred in Thellungiella; both species accumulated ABA and JA with a similar trend although Arabidopsis showed higher concentrations of both hormones which indicated a stronger impact of desiccation on Arabidopsis. However, Arabidopsis showed a higher number of significantly altered mass features than Thellungiella. Under salt stress, Thellungiella plants accumulated lower amounts of Cl(-) ions than Arabidopsis but exhibited a similar proline response. Under these conditions, ABA and JA levels increased in Arabidopsis whereas minimal changes in both hormone concentrations were recorded in Thellungiella. Contrastingly, the impact of salt stress on metabolite profiles was higher in Thellungiella than in Arabidopsis. Overall, data indicated that physiological responses in Arabidopsis are induced after stress imposition through hormonal regulation whereas Thellungiella has a basal metabolic configuration, better prepared to endure environmental cues.

  2. Genotype-environment interactions affecting preflowering physiological and morphological traits of Brassica rapa grown in two watering regimes.

    PubMed

    El-Soda, Mohamed; Boer, Martin P; Bagheri, Hedayat; Hanhart, Corrie J; Koornneef, Maarten; Aarts, Mark G M

    2014-02-01

    Plant growth and productivity are greatly affected by drought, which is likely to become more threatening with the predicted global temperature increase. Understanding the genetic architecture of complex quantitative traits and their interaction with water availability may lead to improved crop adaptation to a wide range of environments. Here, the genetic basis of 20 physiological and morphological traits is explored by describing plant performance and growth in a Brassica rapa recombinant inbred line (RIL) population grown on a sandy substrate supplemented with nutrient solution, under control and drought conditions. Altogether, 54 quantitative trait loci (QTL) were identified, of which many colocated in 11 QTL clusters. Seventeen QTL showed significant QTL-environment interaction (Q×E), indicating genetic variation for phenotypic plasticity. Of the measured traits, only hypocotyl length did not show significant genotype-environment interaction (G×E) in both environments in all experiments. Correlation analysis showed that, in the control environment, stomatal conductance was positively correlated with total leaf dry weight (DW) and aboveground DW, whereas in the drought environment, stomatal conductance showed a significant negative correlation with total leaf DW and aboveground DW. This correlation was explained by antagonistic fitness effects in the drought environment, controlled by a QTL cluster on chromosome A7. These results demonstrate that Q×E is an important component of the genetic variance and can play a great role in improving drought tolerance in future breeding programmes. PMID:24474811

  3. Genotype–environment interactions affecting preflowering physiological and morphological traits of Brassica rapa grown in two watering regimes

    PubMed Central

    Aarts, Mark G. M.

    2014-01-01

    Plant growth and productivity are greatly affected by drought, which is likely to become more threatening with the predicted global temperature increase. Understanding the genetic architecture of complex quantitative traits and their interaction with water availability may lead to improved crop adaptation to a wide range of environments. Here, the genetic basis of 20 physiological and morphological traits is explored by describing plant performance and growth in a Brassica rapa recombinant inbred line (RIL) population grown on a sandy substrate supplemented with nutrient solution, under control and drought conditions. Altogether, 54 quantitative trait loci (QTL) were identified, of which many colocated in 11 QTL clusters. Seventeen QTL showed significant QTL–environment interaction (Q×E), indicating genetic variation for phenotypic plasticity. Of the measured traits, only hypocotyl length did not show significant genotype–environment interaction (G×E) in both environments in all experiments. Correlation analysis showed that, in the control environment, stomatal conductance was positively correlated with total leaf dry weight (DW) and aboveground DW, whereas in the drought environment, stomatal conductance showed a significant negative correlation with total leaf DW and aboveground DW. This correlation was explained by antagonistic fitness effects in the drought environment, controlled by a QTL cluster on chromosome A7. These results demonstrate that Q×E is an important component of the genetic variance and can play a great role in improving drought tolerance in future breeding programmes. PMID:24474811

  4. A comparison of physiological and transcriptome responses to water deprivation and salt loading in the rat supraoptic nucleus.

    PubMed

    Greenwood, Michael P; Mecawi, Andre S; Hoe, See Ziau; Mustafa, Mohd Rais; Johnson, Kory R; Al-Mahmoud, Ghada A; Elias, Lucila L K; Paton, Julian F R; Antunes-Rodrigues, Jose; Gainer, Harold; Murphy, David; Hindmarch, Charles C T

    2015-04-01

    Salt loading (SL) and water deprivation (WD) are experimental challenges that are often used to study the osmotic circuitry of the brain. Central to this circuit is the supraoptic nucleus (SON) of the hypothalamus, which is responsible for the biosynthesis of the hormones, arginine vasopressin (AVP) and oxytocin (OXT), and their transport to terminals that reside in the posterior lobe of the pituitary. On osmotic challenge evoked by a change in blood volume or osmolality, the SON undergoes a function-related plasticity that creates an environment that allows for an appropriate hormone response. Here, we have described the impact of SL and WD compared with euhydrated (EU) controls in terms of drinking and eating behavior, body weight, and recorded physiological data including circulating hormone data and plasma and urine osmolality. We have also used microarrays to profile the transcriptome of the SON following SL and remined data from the SON that describes the transcriptome response to WD. From a list of 2,783 commonly regulated transcripts, we selected 20 genes for validation by qPCR. All of the 9 genes that have already been described as expressed or regulated in the SON by osmotic stimuli were confirmed in our models. Of the 11 novel genes, 5 were successfully validated while 6 were false discoveries.

  5. Water clarity, maternal behavior, and physiology combine to eliminate UV radiation risk to amphibians in a montane landscape.

    PubMed

    Palen, Wendy J; Schindler, Daniel E

    2010-05-25

    Increasing UV-B radiation (UV-B; 290-320 nm) due to stratospheric ozone depletion has been a leading explanation for the decline in amphibians for nearly 2 decades. Yet, the likelihood that UV-B can influence amphibians at the large spatial scales relevant to population declines has not yet been evaluated. A key limitation has been in relating results from individual sites to the effect of UV-B for populations distributed across heterogeneous landscapes. We measured critical embryonic exposures to UV-B for two species of montane amphibians with contrasting physiological sensitivities, long-toed salamander (Ambystoma macrodactylum) and Cascades frog (Rana cascadae), at field sites spanning a gradient of UV-B attenuation in water. We then used these experimental results to estimate the proportion of embryos exposed to harmful UV-B across a large number of breeding sites. By combining surveys of the incubation timing, incident UV-B, optical transparency of water, and oviposition depth and light exposure of embryos at each site, we present a comprehensive assessment of the risk posed by UV-B for montane amphibians of the Pacific Northwest. We found that only 1.1% of A. macrodactylum and no R. cascadae embryos across a landscape of breeding sites are exposed to UV-B exceeding lethal levels. These results emphasize that accurately estimating the risk posed by environmental stressors requires placing experimental results in a broader ecological context that accounts for the heterogeneity experienced by populations distributed across natural landscapes. PMID:20479221

  6. Degradation characteristics of hydroxyapatite coatings on orthopaedic TiAlV in simulated physiological media investigated by electrochemical impedance spectroscopy.

    PubMed

    Souto, Ricardo M; Laz, María M; Reis, Rui L

    2003-10-01

    This paper concentrates on the degradation characteristics of hydroxyapatite (HA) coatings on orthopaedic Ti-6Al-4V alloy while immersed in Ringer's salt solution, which were investigated by electrochemical impedance spectroscopy. Electrochemical impedance spectroscopy measurements were used to in situ characterize the electrochemical behavior of the passivated alloy covered with HA during aging in Ringer's solution. Comparison of the electrochemical data for the coated material with that for the uncoated metal substrate was also performed. The characteristic feature that describes the electrochemical behavior of the coated material is the coexistence of large areas of the coating itself with pores where the substrate is exposed to the aggressive media. The interpretation of results was thus performed in terms of a two-layer model of the film, in which the precipitation of hydrated oxide or phosphate compounds seals the pores left by the ceramic coating. The blocking effect due to salt precipitation inside the pores produces an enhancement of the resistance values, thus effectively diminishing the metal ion release in the system.

  7. An investigation of spectral characteristics of water-glucose solutions

    NASA Astrophysics Data System (ADS)

    Lastovskaia, Elena A.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Korotaev, Valery V.

    2016-04-01

    One of the problems of modern medical device engineering is the development of an instrument for non-invasive monitoring of glucose levels in the blood. The urgency of this task is ensured by the following facts: the increase in the incidence of diabetes, the need for regular monitoring of blood sugar, and pain of modern methods of glycemia measurement. The problem can be solved with the help of a spectrophotometric method. This report is devoted to the investigation of spectral characteristics of glucose solution with various molar concentrations. The authors proposed the methodology of experimental research and data processing algorithm. The results of the experimental studies confirmed potential opportunity of blood sugar control by spectrophotometric method. Further research is expected to continue by the way of complication of the composition of the object from an aqueous solution of glucose to biological object.

  8. Water isotope characteristics of landfalling atmospheric rivers in California

    NASA Astrophysics Data System (ADS)

    Mix, H.; Reilly, S. P.; Martin, A.; Kawzenuk, B.

    2015-12-01

    Atmospheric rivers (ARs) are a defining feature of mid-latitude water vapor transport, responsible for 30-50% of the precipitation delivered to the western US on an annual basis. Despite the growing number of intra-event stable isotope studies, water isotope time series has only been examined for a single AR event to date. Here, we present hourly oxygen and hydrogen isotopes in precipitation for two AR events: 1) A December 10-12 event, collected in Santa Clara, CA; and 2) Four precipitation time series collected during the February 6-8 AR event in Cazadero, CA. During the December event, δ18O values decrease steadily from ~ -2 to ~ -20 ‰, with the exception of the 6 hours leading to the passage of the cold front at the surface. During this period, d-excess values decreases by 10-15 ‰, consistent with a transition between multiple moisture sources. Three of four February precipitation events exhibit V-shapes of up to 6 ‰ in δ18O values. Such patterns have been observed in a prior AR event as well as other mid-latitude cyclones, and may reflect changes in post-condensation exchange related to cold front passage. Future work will incorporate additional meteorological in-situ and satellite-derived observations in order to gain insight into the atmospheric river dynamics.

  9. Survey of receiving-water environmental impacts associated with discharges from pulp mills; 1: Mill characteristics, receiving-water chemical profiles and lab toxicity tests

    SciTech Connect

    Robinson, R.D. . Dept. of Environmental Biology); Carey, J.H. . Rivers Research Branch); Solomon, K.R. ); Smith, I.R. . Water Resources Branch); Servos, M.R.; Munkittrick, K.R. . Great Lakes Lab. for Fisheries and Aquatic Sciences)

    1994-07-01

    This survey examined the relationship between environmental responses at pulp mill sites and the pulping process, effluent treatment, and bleaching technology used by pulp mills. This manuscript is the first in a series of four; it reviews the location and operating characteristics of mills included in the survey and provides background information on water chemistry that is relevant to the other components of the survey. In addition, lab 7-d toxicity tests of receiving water were conducted using fathead minnows (Pimephales promelas) and the cladoceran Ceriodaphnia dubia with water samples collected upstream and downstream of effluent discharges at 11 Canadian pulp and paper mills; these samples were collected at the same time as fish surveys were conducted. Survival of fathead minnow larvae was significantly reduced at four of the 11 downstream sites. Ceriodaphnia reproduction was significantly higher at six of the 11 downstream sites and significantly lower at two downstream sites. There were no significant effects on fathead minnow larva growth or adult Ceriodaphnia survival at any of the examined downstream sites. Negative effects in the toxicity tests were generally associated with the low dilution discharge of primary treated effluent with a previous history of acute toxicity. Fathead minnow and Ceriodaphnia tests were generally correlated with historical data on benthic macroinvertebrate community responses. Neither toxicity test predicted the physiological changes in wild fish that are presented in accompanying papers.

  10. Carbon and water flux responses to physiology by environment interactions: a sensitivity analysis of variation in climate on photosynthetic and stomatal parameters

    NASA Astrophysics Data System (ADS)

    Bauerle, William L.; Daniels, Alex B.; Barnard, David M.

    2014-05-01

    Sensitivity of carbon uptake and water use estimates to changes in physiology was determined with a coupled photosynthesis and stomatal conductance ( g s) model, linked to canopy microclimate with a spatially explicit scheme (MAESTRA). The sensitivity analyses were conducted over the range of intraspecific physiology parameter variation observed for Acer rubrum L. and temperate hardwood C3 (C3) vegetation across the following climate conditions: carbon dioxide concentration 200-700 ppm, photosynthetically active radiation 50-2,000 μmol m-2 s-1, air temperature 5-40 °C, relative humidity 5-95 %, and wind speed at the top of the canopy 1-10 m s-1. Five key physiological inputs [quantum yield of electron transport ( α), minimum stomatal conductance ( g 0), stomatal sensitivity to the marginal water cost of carbon gain ( g 1), maximum rate of electron transport ( J max), and maximum carboxylation rate of Rubisco ( V cmax)] changed carbon and water flux estimates ≥15 % in response to climate gradients; variation in α, J max, and V cmax input resulted in up to ~50 and 82 % intraspecific and C3 photosynthesis estimate output differences respectively. Transpiration estimates were affected up to ~46 and 147 % by differences in intraspecific and C3 g 1 and g 0 values—two parameters previously overlooked in modeling land-atmosphere carbon and water exchange. We show that a variable environment, within a canopy or along a climate gradient, changes the spatial parameter effects of g 0, g 1, α, J max, and V cmax in photosynthesis- g s models. Since variation in physiology parameter input effects are dependent on climate, this approach can be used to assess the geographical importance of key physiology model inputs when estimating large scale carbon and water exchange.

  11. Anatomical and physiological characteristics of vestibular neurons mediating the vertical vestibulo-ocular reflexes of the squirrel monkey.

    PubMed

    McCrea, R A; Strassman, A; Highstein, S M

    1987-10-22

    The morphology of 35 vestibular neurons whose firing rate was related to vertical eye movements was studied by injection of horseradish peroxidase intracellularly into physiologically identified vestibular axons in alert squirrel monkeys. The intracellularly injected cells were readily classified into four main groups. One group of cells, down position-vestibular-pause neurons (down PVPs; N = 12), increased their firing rate during downward eye positions, paused during saccades, and were located in the medial vestibular nucleus (MV) and the adjacent ventrolateral vestibular nucleus (VLV). They had axons that crossed the midline and ascended in the medial longitudinal fasciculus (MLF) to terminate in the trochlear nucleus, the lateral aspect of the caudal oculomotor nucleus, and the dorsal aspect of the rostral oculomotor nucleus. A second group of cells (N = 15) were also located in the MV and VLV, but increased their firing rate during upward eye positions, and paused during saccades. These cells had axons that crossed the midline and ascended in the contralateral MLF to terminate in the medial aspect of the oculomotor nucleus. A third group of cells (N = 4) were located in the superior vestibular nucleus, generated bursts of spikes during upward saccades, and increased their tonic firing rate during upward eye positions. These cells had axons that ascended laterally to the ipsilateral MLF to terminate in regions of the trochlear and oculomotor nuclei similar to those in which down PVPs terminated. A fourth group of cells (N = 4), located in the VLV, had axons that projected to the spinal cord, although they had firing rates that were significantly correlated with vertical eye position. Electrical stimulation of the vestibular nerve evoked spikes at monosynaptic latencies in each of the above classes of cells, six of which were injected with horseradish peroxidase. Each group of cells had collateral projections to other areas of the brainstem. Some of the neurons

  12. Toxic Effects of Ethyl Cinnamate on the Photosynthesis and Physiological Characteristics of Chlorella vulgaris Based on Chlorophyll Fluorescence and Flow Cytometry Analysis

    PubMed Central

    Jiao, Yang; Ouyang, Hui-Ling; Jiang, Yu-Jiao; Kong, Xiang-Zhen; He, Wei; Liu, Wen-Xiu; Yang, Bin; Xu, Fu-Liu

    2015-01-01

    The toxic effects of ethyl cinnamate on the photosynthetic and physiological characteristics of Chlorella vulgaris were studied based on chlorophyll fluorescence and flow cytometry analysis. Parameters, including biomass, Fv/Fm (maximal photochemical efficiency of PSII), ФPSII (actual photochemical efficiency of PSII in the light), FDA, and PI staining fluorescence, were measured. The results showed the following: (1) The inhibition on biomass increased as the exposure concentration increased. 1 mg/L ethyl cinnamate was sufficient to reduce the total biomass of C. vulgaris. The 48-h and 72-h EC50 values were 2.07 mg/L (1.94–2.20) and 1.89 mg/L (1.82–1.97). (2) After 24 h of exposure to 2–4 mg/L ethyl cinnamate, the photosynthesis of C. vulgaris almost ceased, manifesting in ФPSII being close to zero. After 72 h of exposure to 4 mg/L ethyl cinnamate, the Fv/Fm of C. vulgaris dropped to zero. (3) Ethyl cinnamate also affected the cellular physiology of C. vulgaris, but these effects resulted in the inhibition of cell yield rather than cell death. Exposure to ethyl cinnamate resulted in decreased esterase activities in C. vulgaris, increased average cell size, and altered intensities of chlorophyll a fluorescence. Overall, esterase activity was the most sensitive variable. PMID:26101784

  13. Toxic Effects of Ethyl Cinnamate on the Photosynthesis and Physiological Characteristics of Chlorella vulgaris Based on Chlorophyll Fluorescence and Flow Cytometry Analysis.

    PubMed

    Jiao, Yang; Ouyang, Hui-Ling; Jiang, Yu-Jiao; Kong, Xiang-Zhen; He, Wei; Liu, Wen-Xiu; Yang, Bin; Xu, Fu-Liu

    2015-01-01

    The toxic effects of ethyl cinnamate on the photosynthetic and physiological characteristics of Chlorella vulgaris were studied based on chlorophyll fluorescence and flow cytometry analysis. Parameters, including biomass, F(v)/F(m) (maximal photochemical efficiency of PSII), Ф(PSII) (actual photochemical efficiency of PSII in the light), FDA, and PI staining fluorescence, were measured. The results showed the following: (1) The inhibition on biomass increased as the exposure concentration increased. 1 mg/L ethyl cinnamate was sufficient to reduce the total biomass of C. vulgaris. The 48-h and 72-h EC50 values were 2.07 mg/L (1.94-2.20) and 1.89 mg/L (1.82-1.97). (2) After 24 h of exposure to 2-4 mg/L ethyl cinnamate, the photosynthesis of C. vulgaris almost ceased, manifesting in Ф(PSII) being close to zero. After 72 h of exposure to 4 mg/L ethyl cinnamate, the Fv /Fm of C. vulgaris dropped to zero. (3) Ethyl cinnamate also affected the cellular physiology of C. vulgaris, but these effects resulted in the inhibition of cell yield rather than cell death. Exposure to ethyl cinnamate resulted in decreased esterase activities in C. vulgaris, increased average cell size, and altered intensities of chlorophyll a fluorescence. Overall, esterase activity was the most sensitive variable. PMID:26101784

  14. Characteristics of sprinklers and water spray mists for fire safety

    NASA Astrophysics Data System (ADS)

    Jackman, Louise A.; Lavelle, Stephen P.; Nolan, P. F.

    1991-04-01

    In order to predict the type of sprinkler or spray head required for fire safety in buildings and transport systems (e.g. aircraft) it is necessary to model the interaction of water droplets with the thermally buoyant fire gases. Such modelling requires a detailed knowledge of the mean droplet size, the droplet size distribution, droplet velocity and trajectory. Many existing systems for the characterisation of droplets are indirect in that an optical property is measured and the results are subject to "black box" data processing. A direct method can be developed using a synchronised metal vapour laser and high speed cine camera with appropriate optics. Results on both sprinkler and spray mist will be presented and a basis for the choice of active fire protection systems will be outlined.

  15. Development Characteristics of PMMA in alternative alcohol:water mixtures

    NASA Astrophysics Data System (ADS)

    Ocola, Leonidas E.

    2015-03-01

    The most widely used resist in electron beam lithography is polymethylmethacrylate (PMMA). The standard developers used are solution mixtures of isopropanol (IPA) and methyl isobutyl ketone (MIBK) in a ratio of 3:1 and mixtures of IPA and water (H2O) in a ratio of 7:3. The Globally Harmonized System (GHS) classification entry for IPA includes: Specific target organ toxicity - single exposure (Category 3). MIBK is much more hazardous than IPA. The only GHS classification entry for Ethanol is: Flammable liquids (Category 2), i.e. more environmentally safe. Using Ethanol/H2O as a developer will therefore enable lower hazardous waste disposal costs to cleanrooms. We find Ethanol/H2O at 85% volume (2:1 molar) exhibits excellent lithography results as good as with IPA/H2O, and better contrast and sensitivity than IPA/H2O and MIBK/IPA developers. Lithographic data shows trends similar to published cosolvency data, but differ too much to be explained by it. In addition, unusual development at 50% volume concentrations for both IPA and Ethanol in H2O show dramatic pothole formation instead of uniform thickness loss found in standard contrast curve exposures. We believe local pockets of concentrated alcohol water molar mixtures are responsible for such behavior. This work was supported by the Department of Energy under Contract No. DE-AC02-06CH11357. Use of the Center for Nanoscale Materials was supported by the U. S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

  16. Still too hot: examination of water temperature and water heater characteristics 24 years after manufacturers adopt voluntary temperature setting.

    PubMed

    Shields, Wendy C; McDonald, Eileen; Frattaroli, Shannon; Perry, Elise C; Zhu, Jeffrey; Gielen, Andrea C

    2013-01-01

    Although water heater manufacturers adopted a voluntary standard in the 1980s to preset thermostats on new water heaters to 120°F, tap water scald burns cause an estimated 1500 hospital admissions and 100 deaths per year in the United States. This study reports on water temperatures in 976 urban homes and identifies water heater and household characteristics associated with having safe temperatures. The temperature of the hot water, type and size of water heater, date of manufacture, and the setting of the temperature gauge were recorded. Demographic data, including number of people living in the home and home ownership, were also recorded. Hot water temperature was unsafe in 41% of homes. Homeowners were more likely to have safer hot water temperature (<120°F) than renters (63 vs 54%; P < .01). For 11% of gas water heaters, the water temperature was >130°F, although the gauge was set at less than 75% of its maximum setting. In a multivariate logistic regression, electric water heaters were more likely to have safe hot water temperatures than gas water heaters (odds ratio R=4.99; P < .01). Water heaters with more gallons per person in the household were more likely to be at or below the recommended 120°F. Our results suggest that hot water temperatures remain dangerously high for a substantial proportion of urban homes despite the adoption of voluntary standards to preset temperature settings by manufacturers. This research highlights the need for improved prevention strategies, such as installing thermostatic mixing valves, to ensure a safer temperature.

  17. Still too hot: Examination of water temperature and water heater characteristics 24 years after manufacturers adopt voluntary temperature setting

    PubMed Central

    Shields, Wendy C.; McDonald, Eileen; Frattaroli, Shannon; Zhu, Jeffrey; Perry, Elise C.; Gielen, Andrea C.

    2013-01-01

    Objective Although water heater manufacturers adopted a voluntary standard in the 1980’s to pre-set thermostats on new water heaters to 120°F, tap water scald burns cause an estimated 1,500 hospital admissions and 100 deaths per year in the United States. This study reports on water temperatures in 976 urban homes and identifies water heater and household characteristics associated with having safe temperatures. Methods The temperature of the hot water, type and size of water heater, date of manufacture and the setting of the temperature gauge were recorded. Demographic data including number of people living in the home and home ownership were also recorded. Results Hot water temperature was unsafe in 41% of homes. Homeowners were more likely to have safer hot water temperature (≤ 120°F) than renters (63% vs. 54%; p<0.01). For 11% of gas water heaters, the water temperature was ≥ 130°F, although the gauge was set at less than 75% of its maximum setting. In a multivariate logistic regression, electric water heaters were more likely to have safe hot water temperatures than gas water heaters (OR=4.99; p<0.01). Water heaters with more gallons per person in the household were more likely to be at or below the recommended 120°F. Conclusions Our results suggest that hot water temperatures remain dangerously high for a substantial proportion of urban homes despite the adoption of voluntary standards to preset temperature settings by manufacturers. This research highlights the need for improved prevention strategies such as installing thermostatic mixing valves to ensure a safer temperature. PMID:23514986

  18. Genotypic differences in physiological characteristics in the tolerance to drought and salinity combined stress between Tibetan wild and cultivated barley.

    PubMed

    Ahmed, Imrul Mosaddek; Dai, Huaxin; Zheng, Weite; Cao, Fangbin; Zhang, Guoping; Sun, Dongfa; Wu, Feibo

    2013-02-01

    Greenhouse pot experiments were conducted to investigate genotypic differences in response to individual and combined stresses of drought and salinity between Tibetan wild barley genotypes (XZ5, drought-tolerant; XZ16, salinity/aluminum tolerant) and cv. CM72 (salinity-tolerant). Either drought (D) or salinity (S) alone and in combination (D + S) stresses significantly decreased plant growth, chlorophyll content, net photosynthetic rate (Pn), maximal photochemical efficiency of PSII (Fv/Fm), water potential and osmotic potential, with the largest suppression under combined stress, and two wild genotypes showing more tolerance than CM72. Water use efficiency (WUE) increased significantly in XZ5 and XZ16 after D + S, but no significant change in CM72. XZ5 and XZ16 showed 30.9% and 12.1% higher K(+) level and 30.5% and 24.1% lower Na(+)/K(+) ratio in plants, compared with CM72, with increased metal nutrients as Ca, Fe and Mn under D + S. The peak accumulation in proline and glycine-beatine was recorded in combined stress with larger accumulation in two wild genotypes. Moreover, larger increases in the level of ASA and GSH, and the activities of Ca(2+)Mg(2+)-ATPase, and superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), guaiacol peroxidase (POD) and glutathione reductase (GR) under D + S vs control were observed in XZ5 and XZ16 than CM72, with less accumulation of H(2)O(2) and malondialdehyde. These results suggest that high tolerance to D + S stress of XZ5 and XZ16 is closely related to lower Na(+)/K(+) ratio and enhanced Ca(2+)Mg(2+)-ATPase, proline, glycine-beatine and WUE, and improved capacity of antioxidative performance to scavenge reactive oxygen species and thus suppressed level of lipid peroxidation. PMID:23232247

  19. Geospatial variation of grapevine water status, soil water availability, grape composition and sensory characteristics in a spatially heterogeneous premium wine grape vineyard

    NASA Astrophysics Data System (ADS)

    Smart, D. R.; Cosby Hess, S.; Plant, R.; Feihn, O.; Heymann, H.; Ebeler, S.

    2014-11-01

    the grape skins showed significant differences in accumulation of amino acids and organic acids. Data vines were categorized as non-stressed (ΨPD ≥ -7.9 bars and ΨL ≥ -14.9 bars) and stressed (ΨPD ≤ -8.0 bars and ΨL ≤ -15.0 bars) and subjected to analysis of variance. Significant separation emerged for vines categorized as non-stressed versus stressed at véraison, which correlated to the areas described as producing higher and lower quality fruit. This report does not advocate the use of stress levels herein reported. The vineyard was planted to a vigorous, deep rooted rootstock (V. rupestris cv. St. George), and from years of management is known to be able to withstand stress levels of the magnitude we observed. Nonetheless, the results may suggest there is not a linear relationship between physiological water stress and grape sensory characteristics, but rather the presence of an inflection point controlling grape composition as well as physiological development.

  20. Agrichemicals in ground water of the midwestern USA: Relations to soil characteristics

    USGS Publications Warehouse

    Burkart, M.R.; Kolpin, D.W.; Jaquis, R.J.; Cole, K.J.

    1999-01-01

    A comprehensive set of soil characteristics were examined to determine the effect of soil on the transport of agrichemicals to ground water. This paper examines the relation of local soil characteristics to concentrations and occurrence of nitrate, atrazine (2-chloro-4 ethylamino-6-isopropylamino-s-trazine), and atrazine residue [atrazine + deethylatrazine (2-amino-4-chloro-6-isopropylamino-s-triazine) + deisopropylatrazine (2-amino-4-chloro-6-ethylamino-s-triazine)] from 99 wells completed in unconsolidated aquifers across the midwestern USA. The occurrence and concentrations of nitrate and atrazine in ground water were directly related to soil characteristics that determine the rate of water movement. The substantial differences in the relations found among soil characteristics and nitrate and atrazine in ground water suggest that different processes affect the transformation, adsorption, and transport of these contaminants. A multivariate analysis determined that the soil characteristics examined explained the amount of variability in concentrations for nitrate (19.0%), atrazine (33.4%), and atrazine residue (28.6%). These results document that, although soils do affect the transport of agrichemicals to ground water, other factors such as hydrology, land use, and climate must also be considered to understand the occurrence of agrichemicals in ground water.

  1. [The medium chain fat acids. Content in food. Physiology, characteristics of metabolism and application in clinical practice].

    PubMed

    Arkhipovskiĭ, A V; Titov, V N

    2013-06-01

    It is rational, according to biology laws and purposes for which cells use fatty acids, to distinguish between saturated (without double bonds in chain), monoene (with one bond), unsaturated (with 2 and 3 double bonds) and polyene (with 4, 5 and 6 double bonds) acids. The saturated and monoene fatty acids are mainly the substratum for oxygenation and working out of energy by cells. The unsaturated fatty acids are the substratum for formation of membranes. The polyene fatty acids are the predecessors of synthesis of eicosanoids and aminophosphotides. With subject to characteristics of metabolism and transfer in vivo, the fatty acids are subdivided into short chain C4 - C8 and medium chain C-10 - C-14 fatty acids. The etherification occurs with glycerin into "short" triglycerides which are not bounded with apoproteins. The long chain fatty acids form "long" triglycerides which in enterocytes are structured by apoprotein B-48 into composition of chylomicrons. It is possible to validly consider that difference in outflow from enterocytes to veins of portal system (which includes veins of omentum) of medium chain fatty acids in the form of short triglycerides can directly input into pathogenesis of syndrome of isolated omental obesity and metabolic syndrome. The another input into the mentioned conditions is the secretion through ductus thoracicus into large veins of greater systemic circulation of long chain fatty acids in the form of triglycerides in the content of chylomicrons. The omental obesity is the only specific symptom of metabolic syndrome.

  2. [Effect of cadmium stress on physiological characteristics of garlic seedlings and the alleviation effects of exogenous calcium].

    PubMed

    Li, He; Lian, Hai-feng; Liu, Shi-qi; Yu, Xin-hui; Sun, Ya-li; Guo, Hui-ping

    2015-04-01

    In the experiment, the effects of exogenous cadmium (Cd2+) and calcium (Ca2+) in nutrient solution on growth, photosynthetic characteristics, enzymes activities, main mineral elements absorption of garlic seedlings were studied. The results showed that cadmium could obviously inhibit the growth of garlic seedlings, decrease the pigment contents and photosynthetic parameters (P(n), E, g(s)) of leaves, reduced the enzymes (SOD, POD, CAT) activities and increase the MDA content of leaves, and also could reduce the N, P, K, Ca, Mg contents and increase the Cd content of roots. The growth was promoted after adding exogenous calcium to garlic seedlings under cadmium stress, which reflected that the morphological indexes were increased at first and then decreased with the increase of exogenous calcium concentrations, and were maximized when the exogenous calcium was 2 or 3 mmol x L(-1). At the same time, the pigment contents and photosynthetic parameters (P(n), E, g(s)) of leaves showed a similar tendency with the morphological indexes, and they were the highest when the exogenous calcium was 2 or 3 mmol x L(-1). In addition, adding exogenous calcium to garlic seedlings under cadmium stress enhanced the enzymes (SOD, POD, CAT) activities and decreased the MDA content of leaves, also added the N, P, K, Ca, Mg contents and reduced the Cd content of roots, and the effect was best when the exogenous calcium concentration was 2 or 3 mmol x L(-1).

  3. Impact of Providing Feed and/or Water on Performance, Physiology, and Behavior of Weaned Pigs during a 32-h Transport

    PubMed Central

    Garcia, Arlene; Sutherland, Mhairi; Pirner, Glenna; Picinin, Guilherme; May, Matthew; Backus, Brittany; McGlone, John

    2016-01-01

    Simple Summary Transportation has the potential to negatively affect the health and welfare of weaned pigs, especially those already experiencing weaning stress. Piglets were transported for 32 h, with and without feed and water, and measures of performance, physiology, and behavior were taken to assess piglet welfare. Transportation negatively impacted body weight, Neutrophil to Lymphocyte Ratio (N:L), and post-transport body weight gain, indicating that not providing water during transport can negatively impact the well-being of recently weaned pigs. Provision of water may aid in reducing stress during long distance transport and improve the animals’ well-being. Abstract Transportation at weaning is a complex stressor made up of many factors, including withdrawal from feed and water, which can potentially negatively affect the health and welfare of pigs, especially those already experiencing weaning stress. The objective of this study was to evaluate the effect of weaning and extended transport durations (up to 32 h), with and without the provision of feed and/or water, on pig welfare. Treatment groups included: pigs neither weaned nor transported, control (CON); weaned pigs transported and provided with feed and water (T+); weaned pigs transported without feed and water (T−); weaned pigs transported with only feed (T+F); and weaned pigs transported with only water provided (TRAN+W). The effect of transport (with and without feed and/or water) on weaned pigs was assessed using behavior, performance, and physiology. After a 32-h transport period, pigs transported without water lost markedly more weight than those transported with water (p < 0.01). Furthermore, the neutrophil to lymphocyte ratio was markedly higher in male pigs transported without water (p < 0.05). Overall, transportation had a negative effect on pig well-being, especially when water was not provided. PMID:27153096

  4. Hydrogeologic characteristics of four public drinking-water supply springs in northern Arkansas

    USGS Publications Warehouse

    Galloway, Joel M.

    2004-01-01

    In October 2000, a study was undertaken by the U.S. Geological Survey (USGS) in cooperation with the Arkansas Department of Health to determine the hydrogeologic characteristics, including the extent of the recharge areas, for Hughes Spring, Stark Spring, Evening Shade Spring, and Roaring Spring, which are used for public-water supply in northern Arkansas. Information pertaining to each spring can be used to enable development of effective management plans to protect these water resources and public health. An integrated approach to determine the ground-water characteristics and the extent of the local recharge areas of the four springs incorporated tools and methods of hydrology, structural geology, geomorphology, geophysics, and geochemistry. Analyses of discharge, temperature, and water quality were completed to describe ground-water flow characteristics, source-water characteristics, and connectivity of the ground-water system with surface runoff. Water-level contour maps were constructed to determine ground-water flow directions and ground-water tracer tests were conducted to determine the extent of the recharge areas and ground-water flow velocities. Hughes Spring supplies water for the city of Marshall, Arkansas, and the surrounding area. The mean annual discharge for Hughes Spring was 2.9 and 5.2 cubic feet per second for water years 2001 and 2002, respectively. Recharge to the spring occurs mainly from the Boone Formation (Springfield Plateau aquifer). Ground-water tracer tests indicate the recharge area for Hughes Spring generally coincides with the surface drainage area (15.8 square miles) and that Hughes Spring is connected directly to the surface flow in Brush Creek. The geochemistry of Hughes Spring demonstrated variations with flow conditions and the influence of surface-runoff in the recharge area. Calcite saturation indices, total dissolved solids concentrations, and hardness demonstrate noticeable differences with flow conditions reflecting the

  5. [Spatial Variability Characteristics of Water Quality and Its Driving Forces in Honghu Lake During High Water-level Period].

    PubMed

    Li, Kun; Wang, Ling; Li, Zhao-hua; Wang, Xiang-rong; Chen, Hong-bing; Wu, Zhong; Zhu, Peng

    2015-04-01

    Based on the high-density analysis of 139 monitoring points and samples in water of honghu lake with different degrees of eutrophication during the high water-level period, we could get the figures of spatial variability characteristics of pollution factors, the biomass of aquatic plants and water quality in Honghu Lake using the GIS interpolation methods. The result showed that the concentrations of TN, TP, NH4(+) -N, permanganate index gradually increased from south to north during this period, the trend of water pollution degree in Honghu Lake was the region of inflowing rivers > enclosure culture area > open water area > the lake protection area > region of the Yangtze river into the lake; and the contribution rate of water quality parameters was in the order of TN > TP > permanganate index > NH4(+), -N > DO; under the influence of industrial sewage, agricultural sewage, domestic sewage, bait, aquatic plants and water exchange, 59% of TN, 35.2% of TP, 13.7% of permanganate index, 4.3% of NH4(+)-N exceeded the water quality targets, respectively, accordingly, 66.2% of the water quality also exceeded the water quality target. Nonetheless, DO reached the water quality target due to the influences of monsoon climate and other environment factors. The spatial variation analysis could directly reflect the mutual interaction among human activity, land-use types and environment factors which had an enormous impact on Honghu Lake water environment. In order to ensure that the lake water environment is beneficial for human productions and livings, it is necessary for us to control the discharge of industrial sewage, agricultural sewage and domestic sewage, as well as the expanding area of aquaculture, all the above measures would be significant for gradually resuming the self-purification capacity of water body and finally achieving the ecological sustainable development of Honghu Lake water environment.

  6. [Spatial Variability Characteristics of Water Quality and Its Driving Forces in Honghu Lake During High Water-level Period].

    PubMed

    Li, Kun; Wang, Ling; Li, Zhao-hua; Wang, Xiang-rong; Chen, Hong-bing; Wu, Zhong; Zhu, Peng

    2015-04-01

    Based on the high-density analysis of 139 monitoring points and samples in water of honghu lake with different degrees of eutrophication during the high water-level period, we could get the figures of spatial variability characteristics of pollution factors, the biomass of aquatic plants and water quality in Honghu Lake using the GIS interpolation methods. The result showed that the concentrations of TN, TP, NH4(+) -N, permanganate index gradually increased from south to north during this period, the trend of water pollution degree in Honghu Lake was the region of inflowing rivers > enclosure culture area > open water area > the lake protection area > region of the Yangtze river into the lake; and the contribution rate of water quality parameters was in the order of TN > TP > permanganate index > NH4(+), -N > DO; under the influence of industrial sewage, agricultural sewage, domestic sewage, bait, aquatic plants and water exchange, 59% of TN, 35.2% of TP, 13.7% of permanganate index, 4.3% of NH4(+)-N exceeded the water quality targets, respectively, accordingly, 66.2% of the water quality also exceeded the water quality target. Nonetheless, DO reached the water quality target due to the influences of monsoon climate and other environment factors. The spatial variation analysis could directly reflect the mutual interaction among human activity, land-use types and environment factors which had an enormous impact on Honghu Lake water environment. In order to ensure that the lake water environment is beneficial for human productions and livings, it is necessary for us to control the discharge of industrial sewage, agricultural sewage and domestic sewage, as well as the expanding area of aquaculture, all the above measures would be significant for gradually resuming the self-purification capacity of water body and finally achieving the ecological sustainable development of Honghu Lake water environment. PMID:26164902

  7. Hydrochemical characteristics and water quality assessment of surface water and groundwater in Songnen plain, Northeast China.

    PubMed

    Zhang, Bing; Song, Xianfang; Zhang, Yinghua; Han, Dongmei; Tang, Changyuan; Yu, Yilei; Ma, Ying

    2012-05-15

    Water quality is the critical factor that influence on human health and quantity and quality of grain production in semi-humid and semi-arid area. Songnen plain is one of the grain bases in China, as well as one of the three major distribution regions of soda saline-alkali soil in the world. To assess the water quality, surface water and groundwater were sampled and analyzed by fuzzy membership analysis and multivariate statistics. The surface water were gather into class I, IV and V, while groundwater were grouped as class I, II, III and V by fuzzy membership analysis. The water samples were grouped into four categories according to irrigation water quality assessment diagrams of USDA. Most water samples distributed in category C1-S1, C2-S2 and C3-S3. Three groups were generated from hierarchical cluster analysis. Four principal components were extracted from principal component analysis. The indicators to water quality assessment were Na, HCO(3), NO(3), Fe, Mn and EC from principal component analysis. We conclude that surface water and shallow groundwater are suitable for irrigation, the reservoir and deep groundwater in upstream are the resources for drinking. The water for drinking should remove of the naturally occurring ions of Fe and Mn. The control of sodium and salinity hazard is required for irrigation. The integrated management of surface water and groundwater for drinking and irrigation is to solve the water issues.

  8. Land use, water use, streamflow characteristics, and water-quality characteristics of the Charlotte Harbor inflow area, Florida

    USGS Publications Warehouse

    Hammett, K.M.

    1990-01-01

    Charlotte Harbor is a 270-square-mile estuarine system in west-central Florida. It is being subjected to increasing environmental stress by rapid population growth and development. By 2020, population in the inflow area may double, which will result in increased demands for freshwater and increased waste loads. The Charlotte Harbor inflow area includes about 4,685 square miles. The Myakka, the Peace, and the Caloosahatchee are the major rivers emptying into the harbor. About 70 percent of the land in these three river basins is used for agriculture and range. In the coastal basin around Charlotte Harbor, about 50 percent of the total land area is devoted to commercial or residential uses. Water use in the inflow area is about 565 million gallons per day, of which 59 percent is used for irrigation, 26 percent for industry, 11 percent for public supply, and 4 percent for rural supply. Total freshwater inflow from the three major rivers, the coastal area, and rainfall directly into Charlotte Harbor averages between 5,700 and 6,100 cubic feet per second, which is more than 3,500 million gallons per day. A trend analysis of about 50 years of streamflow data shows a statistically significant decreasing trend for the Peace River stations at Bartow, Zolfo Springs, and Arcadia. No significant trend has been observed in the Myakka or the Caloosahatchee River data. In the Peace River, the decrease in flow may be related to a long-term decline in the potentiometric surface of the underlying Floridan aquifer system, which resulted from ground-water withdrawals. It is not possible to determine whether the trend will continue. However, if it does continue at the same rate, then, except for brief periods of storm runoff, the Peace River at Zolfo Springs could be dry year-round in about 100 years. Of the 114 facilities permitted to discharge domestic or industrial effluent to waters tributary to Charlotte Harbor, 88 are in the Peace River basin. Phosphate ore and citrus processing

  9. Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism.

    PubMed

    Shaik, Shahnoor S; Obata, Toshihiro; Hebelstrup, Kim H; Schwahn, Kevin; Fernie, Alisdair R; Mateiu, Ramona V; Blennow, Andreas

    2016-01-01

    Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD.

  10. Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism.

    PubMed

    Shaik, Shahnoor S; Obata, Toshihiro; Hebelstrup, Kim H; Schwahn, Kevin; Fernie, Alisdair R; Mateiu, Ramona V; Blennow, Andreas

    2016-01-01

    Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365

  11. Starch Granule Re-Structuring by Starch Branching Enzyme and Glucan Water Dikinase Modulation Affects Caryopsis Physiology and Metabolism

    PubMed Central

    Shaik, Shahnoor S.; Obata, Toshihiro; Hebelstrup, Kim H.; Schwahn, Kevin; Fernie, Alisdair R.; Mateiu, Ramona V.; Blennow, Andreas

    2016-01-01

    Starch is of fundamental importance for plant development and reproduction and its optimized molecular assembly is potentially necessary for correct starch metabolism. Re-structuring of starch granules in-planta can therefore potentially affect plant metabolism. Modulation of granule micro-structure was achieved by decreasing starch branching and increasing starch-bound phosphate content in the barley caryopsis starch by RNAi suppression of all three Starch Branching Enzyme (SBE) isoforms or overexpression of potato Glucan Water Dikinase (GWD). The resulting lines displayed Amylose-Only (AO) and Hyper-Phosphorylated (HP) starch chemotypes, respectively. We studied the influence of these alterations on primary metabolism, grain composition, starch structural features and starch granule morphology over caryopsis development at 10, 20 and 30 days after pollination (DAP) and at grain maturity. While HP showed relatively little effect, AO showed significant reduction in starch accumulation with re-direction to protein and β-glucan (BG) accumulation. Metabolite profiling indicated significantly higher sugar accumulation in AO, with re-partitioning of carbon to accumulate amino acids, and interestingly it also had high levels of some important stress-related metabolites and potentially protective metabolites, possibly to elude deleterious effects. Investigations on starch molecular structure revealed significant increase in starch phosphate and amylose content in HP and AO respectively with obvious differences in starch granule morphology at maturity. The results demonstrate that decreasing the storage starch branching resulted in metabolic adjustments and re-directions, tuning to evade deleterious effects on caryopsis physiology and plant performance while only little effect was evident by increasing starch-bound phosphate as a result of overexpressing GWD. PMID:26891365

  12. Neuroanatomical distribution of angiotensin-II-like neuropeptide within the central nervous system of the crab Chasmagnathus; physiological changes triggered by water deprivation.

    PubMed

    Frenkel, Lia; Dimant, Beatriz; Portiansky, Enrique L; Imboden, Hans; Maldonado, Héctor; Delorenzi, Alejandro

    2010-07-01

    The angiotensins constitute a neuropeptidergic system that emerged early in evolution. Their classical osmoregulatory and dipsogenic functions and their mnemonic actions have been demonstrated both in vertebrates and in some invertebrates. Previously, we have shown that, in the euryhaline and semiterrestrial crab Chasmagnathus granulatus, water deprivation correlates with an increased level of brain angiotensin-II-like neuropeptide/s (ANGII-like) and improves memory processes through ANGII receptors. We have proposed that the release of brain angiotensins in response to water shortages is an ancient mechanism for coordinating various functions that, together, enable organisms to tolerate this environmental change. Here, we have evaluated the physiological changes in ANGII-like levels in diverse structures of the central nervous system of these animals during water deprivation. The neuroanatomical distribution of ANGII-like is described in the optic lobes and brain of Chasmagnathus granulatus and the physiological changes in ANGII-like distribution in various brain neuropils is evaluated after water deprivation. Our results indicate that ANGII-like is widely distributed, especially in the medial protocerebrum. After 2 h of water deprivation, ANGII-like immunoreactivity increases in the central body and decreases in the olfactory neuropil and, after 6 h of water deprivation, is markedly reduced in several brain areas. Although further experiments are needed to establish that the angiotensinergic system is involved in the balance of body fluids in this crab, our results suggest that ANGII regulates several functions during water shortages.

  13. Influence of Prior Intense Exercise and Cold Water Immersion in Recovery for Performance and Physiological Response during Subsequent Exercise.

    PubMed

    Christensen, Peter M; Bangsbo, Jens

    2016-01-01

    Athletes in intense endurance sports (e.g., 4000-m track cycling) often perform maximally (~4 min) twice a day due to qualifying and finals being placed on the same day. The purpose of the present study was to evaluate repeated performance on the same day in a competitive setting (part A) and the influence from prior intense exercise on subsequent performance and physiological response to moderate and maximal exercise with and without the use of cold water immersion (CWI) in recovery (part B). In part A, performance times during eight World championships for male track cyclists were extracted from the qualifying and final races in 4000-m individual pursuit. In part B, twelve trained cyclists with an average (±SD) ⩒O2-peak of 67 ± 5 mL/min/kg performed a protocol mimicking a qualifying race (QUAL) followed 3 h later by a performance test (PT) with each exercise period encompassing intense exercise for ~4 min preceded by an identical warm-up period in both a control setting (CON) and using cold water immersion in recovery (CWI; 15 min at 15°C). Performance was lowered (P < 0.001) from qualification to finals (259 ± 3 vs. 261 ± 3 s) for the track cyclists during World championships in part A. In part B, mean power in PT was not different in CWI relative to CON (406 ± 43 vs. 405 ± 38 W). Peak ⩒O2 (5.04 ± 0.50 vs. 5.00 ± 0.49 L/min) and blood lactate (13 ± 3 vs. 14 ± 3 mmol/L) did not differ between QUAL and PT and cycling economy and potassium handling was not impaired by prior intense exercise. In conclusion, performance is reduced with repeated maximal exercise in world-class track cyclists during 4000-m individual pursuit lasting ~4 min, however prior intense exercise do not appear to impair peak ⩒O2, peak lactate, cycling economy, or potassium handling in trained cyclists and CWI in recovery does not improve subsequent performance. PMID:27445857

  14. Influence of Prior Intense Exercise and Cold Water Immersion in Recovery for Performance and Physiological Response during Subsequent Exercise.

    PubMed

    Christensen, Peter M; Bangsbo, Jens

    2016-01-01

    Athletes in intense endurance sports (e.g., 4000-m track cycling) often perform maximally (~4 min) twice a day due to qualifying and finals being placed on the same day. The purpose of the present study was to evaluate repeated performance on the same day in a competitive setting (part A) and the influence from prior intense exercise on subsequent performance and physiological response to moderate and maximal exercise with and without the use of cold water immersion (CWI) in recovery (part B). In part A, performance times during eight World championships for male track cyclists were extracted from the qualifying and final races in 4000-m individual pursuit. In part B, twelve trained cyclists with an average (±SD) ⩒O2-peak of 67 ± 5 mL/min/kg performed a protocol mimicking a qualifying race (QUAL) followed 3 h later by a performance test (PT) with each exercise period encompassing intense exercise for ~4 min preceded by an identical warm-up period in both a control setting (CON) and using cold water immersion in recovery (CWI; 15 min at 15°C). Performance was lowered (P < 0.001) from qualification to finals (259 ± 3 vs. 261 ± 3 s) for the track cyclists during World championships in part A. In part B, mean power in PT was not different in CWI relative to CON (406 ± 43 vs. 405 ± 38 W). Peak ⩒O2 (5.04 ± 0.50 vs. 5.00 ± 0.49 L/min) and blood lactate (13 ± 3 vs. 14 ± 3 mmol/L) did not differ between QUAL and PT and cycling economy and potassium handling was not impaired by prior intense exercise. In conclusion, performance is reduced with repeated maximal exercise in world-class track cyclists during 4000-m individual pursuit lasting ~4 min, however prior intense exercise do not appear to impair peak ⩒O2, peak lactate, cycling economy, or potassium handling in trained cyclists and CWI in recovery does not improve subsequent performance.

  15. Influence of Prior Intense Exercise and Cold Water Immersion in Recovery for Performance and Physiological Response during Subsequent Exercise

    PubMed Central

    Christensen, Peter M.; Bangsbo, Jens

    2016-01-01

    Athletes in intense endurance sports (e.g., 4000-m track cycling) often perform maximally (~4 min) twice a day due to qualifying and finals being placed on the same day. The purpose of the present study was to evaluate repeated performance on the same day in a competitive setting (part A) and the influence from prior intense exercise on subsequent performance and physiological response to moderate and maximal exercise with and without the use of cold water immersion (CWI) in recovery (part B). In part A, performance times during eight World championships for male track cyclists were extracted from the qualifying and final races in 4000-m individual pursuit. In part B, twelve trained cyclists with an average (±SD) ⩒O2-peak of 67 ± 5 mL/min/kg performed a protocol mimicking a qualifying race (QUAL) followed 3 h later by a performance test (PT) with each exercise period encompassing intense exercise for ~4 min preceded by an identical warm-up period in both a control setting (CON) and using cold water immersion in recovery (CWI; 15 min at 15°C). Performance was lowered (P < 0.001) from qualification to finals (259 ± 3 vs. 261 ± 3 s) for the track cyclists during World championships in part A. In part B, mean power in PT was not different in CWI relative to CON (406 ± 43 vs. 405 ± 38 W). Peak ⩒O2 (5.04 ± 0.50 vs. 5.00 ± 0.49 L/min) and blood lactate (13 ± 3 vs. 14 ± 3 mmol/L) did not differ between QUAL and PT and cycling economy and potassium handling was not impaired by prior intense exercise. In conclusion, performance is reduced with repeated maximal exercise in world-class track cyclists during 4000-m individual pursuit lasting ~4 min, however prior intense exercise do not appear to impair peak ⩒O2, peak lactate, cycling economy, or potassium handling in trained cyclists and CWI in recovery does not improve subsequent performance. PMID:27445857

  16. Morphological characteristics of urban water bodies: mechanisms of change and implications for ecosystem function.

    PubMed

    Steele, M K; Heffernan, J B

    2014-07-01

    The size, shape, and connectivity of water bodies (lakes, ponds, and wetlands) can have important effects on ecological communities and ecosystem processes, but how these characteristics are influenced by land use and land cover change over broad spatial scales is not known. Intensive alteration of water bodies during urban development, including construction, burial, drainage, and reshaping, may select for certain morphometric characteristics and influence the types of water bodies present in cities. We used a database of over one million water bodies in 100 cities across the conterminous United States to compare the size distributions, connectivity (as intersection with surface flow lines), and shape (as measured by shoreline development factor) of water bodies in different land cover classes. Water bodies in all urban land covers were dominated by lakes and ponds, while reservoirs and wetlands comprised only a small fraction of the sample. In urban land covers, as compared to surrounding undeveloped land, water body size distributions converged on moderate sizes, shapes toward less tortuous shorelines, and the number and area of water bodies that intersected surface flow lines (i.e., streams and rivers) decreased. Potential mechanisms responsible for changing the characteristics of urban water bodies include: preferential removal, physical reshaping or addition of water bodies, and selection of locations for development. The relative contributions of each mechanism likely change as cities grow. The larger size and reduced surface connectivity of urban water bodies may affect the role of internal dynamics and sensitivity to catchment processes. More broadly, these results illustrate the complex nature of urban watersheds and highlight the need to develop a conceptual framework for urban water bodies.

  17. [Nitrogen and phosphate pollution characteristics and eutrophication evaluation for typical urban landscape waters in Hefei City].

    PubMed

    Li, Ru-Zhong; Liu, Ke-Feng; Qian, Jing; Yang, Ji-Wei; Zhang, Pian-Pian

    2014-05-01

    To understand the water environment regimes of the city-circling water system in Hefei City, six typical landscape waters were chosen to investigate pollution characteristics of nitrogen and phosphate and evaluate water eutrophication level according to the monitoring data of water physicochemical characteristics and chlorophyll content from September 2012 to July 2013. Study results showed that (1) the six waters mentioned above have been seriously polluted by nitrogen and phosphorus loadings, with the monthly mean values of total nitrogen (TN) and total phosphorus (TP) concentrations far exceeding the universally accepted threshold values of water eutrophication; (2) the nitrogen contents in the waters of Nanfeihe River, Heichiba and Yuhuatang scenic spots exhibited a markedly monthly variation, and both TP and PO(3-)(4)-P in Nanfeihe River showed a fluctuated characteristic with high concentrations while presenting a significant upward trend in Yuhuatang scenic spot; (3) the average values of TN/TP ratios for Yuhuatang and Heichiba scenic spots were 104.7 and 158.3, respectively, and the ratios for Baohe Park, Yinhe Park, Xiaoyaojin Park, and city segment of Nanfeihe River were 16.8, 18.7, 6.4 and 16.8, respectively, indicating that the scenic waters of Yuhuatang and Heichiba were phosphate-limited whereas Xiaoyaojin Park was nitrogen-limited; (4) all the six scenic waters were, in general, subsumed under just two broad categories, namely Hechiba scenic spot and Nanfeihe River, which were seriously polluted, and clustered together, and the others fall into the second class; and (5) water eutrophication appraisal result indicated that the six waters were all in the state of eutrophication, and could be arranged in the order of eutrophication level, Yinhe Park > Heichiba scenic spot > city segment of Nanfeihe River > Xiaoyaojin Park > Yuhuatang scenic spot > Baohe Park.

  18. Morphological and physicochemical characteristics of iron corrosion scales formed under different water source histories in a drinking water distribution system.

    PubMed

    Yang, Fan; Shi, Baoyou; Gu, Junnong; Wang, Dongsheng; Yang, Min

    2012-10-15

    The corrosion scales on iron pipes could have great impact on the water quality in drinking water distribution systems (DWDS). Unstable and less protective corrosion scale is one of the main factors causing "discolored water" issues when quality of water entering into distribution system changed significantly. The morphological and physicochemical characteristics of corrosion scales formed under different source water histories in duration of about two decades were systematically investigated in this work. Thick corrosion scales or densely distributed corrosion tubercles were mostly found in pipes transporting surface water, but thin corrosion scales and hollow tubercles were mostly discovered in pipes transporting groundwater. Magnetite and goethite were main constituents of iron corrosion products, but the mass ratio of magnetite/goethite (M/G) was significantly different depending on the corrosion scale structure and water source conditions. Thick corrosion scales and hard shell of tubercles had much higher M/G ratio (>1.0), while the thin corrosion scales had no magnetite detected or with much lower M/G ratio. The M/G ratio could be used to identify the characteristics and evaluate the performances of corrosion scales formed under different water conditions. Compared with the pipes transporting ground water, the pipes transporting surface water were more seriously corroded and could be in a relatively more active corrosion status all the time, which was implicated by relatively higher siderite, green rust and total iron contents in their corrosion scales. Higher content of unstable ferric components such as γ-FeOOH, β-FeOOH and amorphous iron oxide existed in corrosion scales of pipes receiving groundwater which was less corroded. Corrosion scales on groundwater pipes with low magnetite content had higher surface area and thus possibly higher sorption capacity. The primary trace inorganic elements in corrosion products were Br and heavy metals. Corrosion

  19. Morphological and physicochemical characteristics of iron corrosion scales formed under different water source histories in a drinking water distribution system.

    PubMed

    Yang, Fan; Shi, Baoyou; Gu, Junnong; Wang, Dongsheng; Yang, Min

    2012-10-15

    The corrosion scales on iron pipes could have great impact on the water quality in drinking water distribution systems (DWDS). Unstable and less protective corrosion scale is one of the main factors causing "discolored water" issues when quality of water entering into distribution system changed significantly. The morphological and physicochemical characteristics of corrosion scales formed under different source water histories in duration of about two decades were systematically investigated in this work. Thick corrosion scales or densely distributed corrosion tubercles were mostly found in pipes transporting surface water, but thin corrosion scales and hollow tubercles were mostly discovered in pipes transporting groundwater. Magnetite and goethite were main constituents of iron corrosion products, but the mass ratio of magnetite/goethite (M/G) was significantly different depending on the corrosion scale structure and water source conditions. Thick corrosion scales and hard shell of tubercles had much higher M/G ratio (>1.0), while the thin corrosion scales had no magnetite detected or with much lower M/G ratio. The M/G ratio could be used to identify the characteristics and evaluate the performances of corrosion scales formed under different water conditions. Compared with the pipes transporting ground water, the pipes transporting surface water were more seriously corroded and could be in a relatively more active corrosion status all the time, which was implicated by relatively higher siderite, green rust and total iron contents in their corrosion scales. Higher content of unstable ferric components such as γ-FeOOH, β-FeOOH and amorphous iron oxide existed in corrosion scales of pipes receiving groundwater which was less corroded. Corrosion scales on groundwater pipes with low magnetite content had higher surface area and thus possibly higher sorption capacity. The primary trace inorganic elements in corrosion products were Br and heavy metals. Corrosion

  20. Cooling cows efficiently with water spray: Behavioral, physiological, and production responses to sprinklers at the feed bunk.

    PubMed

    Chen, Jennifer M; Schütz, Karin E; Tucker, Cassandra B

    2016-06-01

    Dairies commonly mount nozzles above the feed bunk that intermittently spray cows to dissipate heat. These sprinklers use potable water-an increasingly scarce resource-but there is little experimental evidence for how much is needed to cool cows in loose housing. Sprinkler flow rate may affect the efficacy of heat abatement, cattle avoidance of spray (particularly on the head), and water waste. Our objectives were to determine how sprinkler flow rate affects cattle behavioral, physiological, and production responses when cows are given 24-h access to spray in freestall housing, and to evaluate heat abatement in relation to water use. We compared 3 treatments: sprinklers that delivered 1.3 or 4.9L/min (both 3min on and 9min off, 24h/d) and an unsprayed control. Nine pairs of high-producing lactating Holstein cows received each treatment at a shaded feed bunk for 2d in a replicated 3×3 Latin square design [air temperature (T): 24-h maximum=33±3°C, mean ± SD]. Cows spent 5.8±0.9h/24h (mean ± SD) at the feed bunk overall, regardless of treatment. With few exceptions, cows responded similarly to the 1.3 and 4.9L/min flow rates. Sprinklers resulted in visits to the feed bunk that were on average 23 to 27% longer and 13 to 16% less frequent compared with the control, perhaps because cows avoided walking through spray. Indeed, when the sprinklers were on, cows left the feed bunk half as often as expected by chance, and when cows chose to walk through spray, they lowered their heads on average 1.7- to 3-fold more often than in the control. Despite possible reluctance to expose their heads to spray, cows did not avoid sprinklers overall. In warmer weather, cows spent more time at the feed bunk when it had sprinklers (on average 19 to 21min/24h for each 1°C increase in T), likely for heat abatement benefits. Compared with the control, sprinklers resulted in 0.3 to 0.7°C lower body temperature from 1300 to 1500h and 1700 to 2000h overall and attenuated the rise in this

  1. Characteristics of Water Vapor Under Partially Cloudy Conditions: Observations by the Atmospheric Infrared Sounder (AIRS)

    NASA Astrophysics Data System (ADS)

    Fishbein, E.

    2003-12-01

    The variability and quality of tropical water vapor derived from the Atmospheric Infrared Sounder (AIRS) are characterized. Profiles of water vapor, temperature and surface characteristics (states) are derived from coincident Advance Microwave Sounding Unit (AMSU) and 3x3 sets of AIRS footprints. States are obtained under partially cloudy conditions by estimating the radiances emitted from the clear portions of the AIRS footprints. This procedure, referred to as cloud clearing, amplifies the measurement noise, and the amplification increases with cloud amount and uniformity. Cumulus and stratus cloud amount are related to the water vapor saturation, and noise amplification and water vapor amount may be partially correlated. The correlations between the uncertainty of retrieved water vapor, cloudiness and noise amplification are characterized. Retrieved water vapor is generally good when the amplification is less than three. Water vapor profiles are compared with correlative data, such as radiosondes and numerical weather center analyses and are in relatively good agreement in the lower troposphere

  2. Analysis of drought characteristics from 1900-2012 for improved understanding of a water resource system

    NASA Astrophysics Data System (ADS)

    Lennard, Amy; Macdonald, Neil; Hooke, Janet

    2014-05-01

    Droughts are a reoccurring feature of the European climate; recent drought events (2004-2006 & 2010-2012) in the UK have highlighted a continued vulnerability to this hazard. The period 2010-2012 was characterised by departures from typical seasonal climatic conditions, resulting in a severe drought which had a severe impact on water resources. This highlighted the need for further understanding of extreme drought events, particularly from a water resource perspective. A number of drought indices are available, which can help to improve our understanding of drought characteristics such as frequency, severity and duration. However, at present little of this is applied to water resource management in the water supply sector. Improved understanding of drought characteristics using indices can inform water resource management plans and enhance future drought resilience. The UK has a rich source of historical rainfall data that has been underutilised in the analysis of drought characteristics at a regional scale. This study applies the standardised precipitation index (SPI) to a series of rainfall records (1900-2012) across the water supply region of a single utility provider. Key multi-year droughts within this period are analysed to develop an understanding of the meteorological characteristics that lead to, exist during and terminate drought events. The results of this analysis highlight how drought severity and duration can vary across a small-scale water supply region, indicating that the spatial coherence of drought events cannot be assumed. Variations in drought duration and severity across a region may have significant implications for water resource management during and after a drought event. A better understanding of regional drought characteristics is achievable by using historical data providing insight for the prediction of future of drought events.

  3. Determination of characteristics and drinking water quality index in Mzuzu City, Northern Malawi

    NASA Astrophysics Data System (ADS)

    Wanda, Elijah M. M.; Gulula, Lewis C.; Phiri, Gift

    An assessment of characteristics and chemical water quality index (WQI) of water supplied by the Northern Region water Board (NRWB) in Mzuzu City was carried out in order to ascertain the quality of water for domestic purposes. The WQI offers a single number that expresses overall water quality for a water sample based on several water quality parameters. In this study raw water and 72 tap water samples were collected monthly between March and September, 2011 and analyzed for major ions, pH, total dissolved solids (TDSs), electrical conductivity (EC), turbidity, total hardness (TH), suspended solids (SSs) and alkalinity using standard methods. The quality and accuracy of the chemical data was assessed by checking electrical balances. The calculated electrical balance errors were found to be less than ±10%, which meant the results were reliable. Based on the Sawyer and McCarty TH classification, 100% of the samples were soft waters (TH < 150 mg/L). Nitrates, which registered medium or average WQ-rating of 69.77 and WQ-rating range of 52.06-86.94, were observed to have significantly affected the overall water quality index of the treated water since the rest of the parameters registered good-excellent WQ-ratings (average WQ-rating: 80.21-97.87). The pH, which is used to determine suitability of water for various purposes, ranged between 6.40 and 6.90 and registered a good water quality rating (WQ rating range: 72.73-87.02) for both raw and treated water. Raw water registered an overall medium water quality rating of 62.67%. Overall, 91.67% of the samples registered a good water quality rating (WQI range: 80.28-88.80%) and 8.33% registered a very good water quality rating (WQI = 90.07%). The results suggested substantial water treatment by the NRWB since the treated water is protected with some negligible degree of impairment that rarely departs from desirable levels of domestic water quality. It is recommended that the WQI should be adopted as a tool to monitor and

  4. Hydathode trichomes actively secreting water from leaves play a key role in the physiology and evolution of root-parasitic rhinanthoid Orobanchaceae

    PubMed Central

    Světlíková, Petra; Hájek, Tomáš; Těšitel, Jakub

    2015-01-01

    Background and Aims Root hemiparasites from the rhinanthoid clade of Orobanchaceae possess metabolically active glandular trichomes that have been suggested to function as hydathode trichomes actively secreting water, a process that may facilitate resource acquisition from the host plant’s root xylem. However, no direct evidence relating the trichomes to water secretion exists, and carbon budgets associated with this energy-demanding process have not been determined. Methods Macro- and microscopic observations of the leaves of hemiparasitic Rhinanthus alectorolophus were conducted and night-time gas exchange was measured. Correlations were examined among the intensity of guttation, respiration and transpiration, and analysis of these correlations allowed the carbon budget of the trichome activity to be quantified. We examined the intensity of guttation, respiration and transpiration, correlations among which indicate active water secretion. Key Results Guttation was observed on the leaves of 50 % of the young, non-flowering plants that were examined, and microscopic observations revealed water secretion from the glandular trichomes present on the abaxial leaf side. Night-time rates of respiration and transpiration and the presence of guttation drops were positively correlated, which is a clear indicator of hydathode trichome activity. Subsequent physiological measurements on older, flowering plants indicated neither intense guttation nor the presence of correlations, which suggests that the peak activity of hydathodes is in the juvenile stage. Conclusions This study provides the first unequivocal evidence for the physiological role of the hydathode trichomes in active water secretion in the rhinanthoid Orobanchaceae. Depending on the concentration of organic elements calculated to be in the host xylem sap, the direct effect of water secretion on carbon balance ranges from close to neutral to positive. However, it is likely to be positive in the xylem-only feeding

  5. Tropine Forming Tropinone Reductase Gene from Withania somnifera (Ashwagandha): Biochemical Characteristics of the Recombinant Enzyme and Novel Physiological Overtones of Tissue-Wide Gene Expression Patterns

    PubMed Central

    Kushwaha, Amit Kumar; Sangwan, Neelam Singh; Trivedi, Prabodh Kumar; Negi, Arvind Singh; Misra, Laxminarain; Sangwan, Rajender Singh

    2013-01-01

    Withania somnifera is one of the most reputed medicinal plants of Indian systems of medicine synthesizing diverse types of secondary metabolites such as withanolides, alkaloids, withanamides etc. Present study comprises cloning and E. coli over-expression of a tropinone reductase gene (WsTR-I) from W. somnifera, and elucidation of biochemical characteristics and physiological role of tropinone reductase enzyme in tropane alkaloid biosynthesis in aerial tissues of the plant. The recombinant enzyme was demonstrated to catalyze NADPH-dependent tropinone to tropine conversion step in tropane metabolism, through TLC, GC and GC-MS-MS analyses of the reaction product. The functionally active homodimeric ∼60 kDa enzyme catalyzed the reaction in reversible manner at optimum pH 6.7. Catalytic kinetics of the enzyme favoured its forward reaction (tropine formation). Comparative 3-D models of landscape of the enzyme active site contours and tropinone binding site were also developed. Tissue-wide and ontogenic stage-wise assessment of WsTR-I transcript levels revealed constitutive expression of the gene with relatively lower abundance in berries and young leaves. The tissue profiles of WsTR-I expression matched those of tropine levels. The data suggest that, in W. somnifera, aerial tissues as well possess tropane alkaloid biosynthetic competence. In vivo feeding of U-[14C]-sucrose to orphan shoot (twigs) and [14C]-chasing revealed substantial radiolabel incorporation in tropinone and tropine, confirming the de novo synthesizing ability of the aerial tissues. This inherent independent ability heralds a conceptual novelty in the backdrop of classical view that these tissues acquire the alkaloids through transportation from roots rather than synthesis. The TR-I gene expression was found to be up-regulated on exposure to signal molecules (methyl jasmonate and salicylic acid) and on mechanical injury. The enzyme's catalytic and structural properties as well as gene expression

  6. Comparison of the physiological responses and time-motion characteristics of young soccer players in small-sided games: the effect of goalkeeper.

    PubMed

    Köklü, Yusuf; Sert, Özcan; Alemdaroğlu, Utku; Arslan, Yunus

    2015-04-01

    The purpose of this study was to investigate the effect of "with goalkeeper" (SSGwith) and "without goalkeeper" (SSGwithout) conditions on players' physiological responses and time-motion characteristics in small-sided games. Sixteen young soccer players (age: 16.5 ± 1.5 years; height: 175.5 ± 5.2 cm; body mass: 63.0 ± 6.9 kg; training experience: 6.3 ± 1.3 years) participated in 2 different 2-a-side, 3-a-side, and 4-a-side games: SSGwith and SSGwithout. The players underwent anthropometric measurements (height and body mass) followed by the Yo-Yo intermittent recovery test (level 1). Then they played 2-a-side, 3-a-side, and 4-a-side SSGwith and SSGwithout soccer-specific SSGs in random order at 2-day intervals. Heart rate (HR) responses and distance covered in different speed zones (walking [WLK, 0-6.9 km·h(-1)], low-intensity running [LIR, 7.0-12.9 km·h(-1)], moderate-intensity running [MIR, 13.0-17.9 km·h(-1)], and high-intensity running [HIR, >18 km·h(-1)]) were measured during the SSGs, whereas the rating of perceived exertion (RPE) and blood lactate (La) were determined at the end of the last bout of each SSG. During the SSGwithout players showed higher %HR, La, and RPE (p ≤ 0.05), greater distance covered in LIR, MIR, HIR, and total distance (p ≤ 0.05) compared with the SSGwith during the 2-a-side, 3-a-side, and 4-a-side games. The results of this study suggest that both SSGwith and SSGwithout could be used for the physiological adaptations required for soccer-specific aerobic endurance. However, if coaches want both higher physiological responses and greater distance covered in the intensity running zone from their teams, SSGwithout should be organized. In addition, this study also suggests that smaller format games (i.e., 2-a-side) may promote some anaerobic adaptations for youth soccer players.

  7. Water-balance characteristics respond to changes in body size in subantarctic weevils.

    PubMed

    Chown, Steven L; Klok, C Jaco

    2003-01-01

    Several environmental factors leading to size-dependent mortality influence insect body size. Few investigations have been concerned with the ways in which the mechanisms underlying variation in water-balance characteristics evolve in response to changes in body size that occur independently of water-balance requirements. Using an explicitly phylogenetic analysis, we show how body size has changed over time in the Ectemnorhinus group of weevils and how water-balance characteristics have evolved in response to this change and changes in habitat use. The basal species in the group are all large bodied and from moist environments. In response to a change in resource availability, there was a marked decline in size within the group. Despite the reduction in water content and dehydration tolerance that this meant, evolution of low whole-animal water-loss rates and high tolerance of dehydration resulted in conservation of desiccation resistance. The return to moist habitats in the group resulted in a reduction in dehydration tolerance and an increase in water-loss rate. Thus, dehydration tolerance and water-loss rate respond rapidly both when there is selection for water conservation and when this requirement is relaxed. Future laboratory selection experiments might usefully explore both directions of water-balance evolution.

  8. Use of an automated chromium reduction system for hydrogen isotope ratio analysis of physiological fluids applied to doubly labeled water analysis.

    PubMed

    Schoeller, D A; Colligan, A S; Shriver, T; Avak, H; Bartok-Olson, C

    2000-09-01

    The doubly labeled water method is commonly used to measure total energy expenditure in free-living subjects. The method, however, requires accurate and precise deuterium abundance determinations, which can be laborious. The aim of this study was to evaluate a fully automated, high-throughput, chromium reduction technique for the measurement of deuterium abundances in physiological fluids. The chromium technique was compared with an off-line zinc bomb reduction technique and also subjected to test-retest analysis. Analysis of international water standards demonstrated that the chromium technique was accurate and had a within-day precision of <1 per thousand. Addition of organic matter to water samples demonstrated that the technique was sensitive to interference at levels between 2 and 5 g l(-1). Physiological samples could be analyzed without this interference, plasma by 10000 Da exclusion filtration, saliva by sedimentation and urine by decolorizing with carbon black. Chromium reduction of urine specimens from doubly labeled water studies indicated no bias relative to zinc reduction with a mean difference in calculated energy expenditure of -0.2 +/- 3.9%. Blinded reanalysis of urine specimens from a second doubly labeled water study demonstrated a test-retest coefficient of variation of 4%. The chromium reduction method was found to be a rapid, accurate and precise method for the analysis of urine specimens from doubly labeled water. PMID:11006607

  9. Use of an automated chromium reduction system for hydrogen isotope ratio analysis of physiological fluids applied to doubly labeled water analysis.

    PubMed

    Schoeller, D A; Colligan, A S; Shriver, T; Avak, H; Bartok-Olson, C

    2000-09-01

    The doubly labeled water method is commonly used to measure total energy expenditure in free-living subjects. The method, however, requires accurate and precise deuterium abundance determinations, which can be laborious. The aim of this study was to evaluate a fully automated, high-throughput, chromium reduction technique for the measurement of deuterium abundances in physiological fluids. The chromium technique was compared with an off-line zinc bomb reduction technique and also subjected to test-retest analysis. Analysis of international water standards demonstrated that the chromium technique was accurate and had a within-day precision of <1 per thousand. Addition of organic matter to water samples demonstrated that the technique was sensitive to interference at levels between 2 and 5 g l(-1). Physiological samples could be analyzed without this interference, plasma by 10000 Da exclusion filtration, saliva by sedimentation and urine by decolorizing with carbon black. Chromium reduction of urine specimens from doubly labeled water studies indicated no bias relative to zinc reduction with a mean difference in calculated energy expenditure of -0.2 +/- 3.9%. Blinded reanalysis of urine specimens from a second doubly labeled water study demonstrated a test-retest coefficient of variation of 4%. The chromium reduction method was found to be a rapid, accurate and precise method for the analysis of urine specimens from doubly labeled water.

  10. [Effects of regulated deficit irrigation on water consumption characteristics and water use efficiency of winter wheat].

    PubMed

    Han, Zhan-Jiang; Yu, Zhen-Wen; Wang, Dong; Wang, Xi-Zhi; Xu, Zhen-Zhu

    2009-11-01

    With the high-yielding winter wheat cultivar Jimai 22 as test material, a field experiment was conducted in Yanzhou of Shandong to examine the effects of regulated deficit irrigation on the water consumption and water use efficiency (WUE) of the cultivar. Five treatments were installed, i.e., the soil relative moisture content at sowing, jointing, and anthesis stages being 80%, 65% and 65% (W0), 80%, 70% and 70% (W1), 80%, 80% and 80% (W2), 90%, 80% and 80% (W3), and 90%, 85% and 85% (W4), respectively. Under the condition of 228 mm precipitation in growth season, the total water consumption was higher in treatments W1 and W4 than in treatments W0, W2, and W3, and no difference was observed between treatments W1 and W4. Comparing with W4, treatment W1 decreased the water storage in 0-200 cm soil layer and the water consumption by wheat from jointing to anthesis stages, but increased the water consumption from anthesis to maturity stages. The water consumption rates at the stages from jointing to anthesis and from anthesis to maturity in treatment W4 were higher. Under regulated deficit irrigation, treatment W0 had higher WUE, but the grain yield was the lowest. The WUE in other treatments increased first, and then decreased with increasing irrigation amount. Both the water consumption and the grain yield were the highest in treatments W1 and W4, and treatment W1 had higher irrigation water use efficiency and irrigation benefit than treatment W4, being the best irrigation regime of high-yielding and water-saving in our study.

  11. Physical characteristics of GE (General Electric) BWR (boiling-water reactor) fuel assemblies

    SciTech Connect

    Moore, R.S.; Notz, K.J.

    1989-06-01

    The physical characteristics of fuel assemblies manufactured by the General Electric Company for boiling-water reactors are classified and described. The classification into assembly types is based on the GE reactor product line, the Characteristics Data Base (CDB) assembly class, and the GE fuel design. Thirty production assembly types are identified. Detailed physical data are presented for each assembly type in an appendix. Descriptions of special (nonstandard) fuels are also reported. 52 refs., 1 fig., 6 tabs.

  12. Variation in water potential, hydraulic characteristics and water source use in montane Douglas-fir and lodgepole pine trees in southwestern Alberta and consequences for seasonal changes in photosynthetic capacity.

    PubMed

    Andrews, Shilo F; Flanagan, Lawrence B; Sharp, Eric J; Cai, Tiebo

    2012-02-01

    Tree species response to climate change-induced shifts in the hydrological cycle depends on many physiological traits, particularly variation in water relations characteristics. We evaluated differences in shoot water potential, vulnerability of branches to reductions in hydraulic conductivity, and water source use between Pinus contorta Dougl. ex Loud. var. latifolia Engelm. (lodgepole pine) and Pseudotsuga menziesii (Mirb.) Franco (interior Douglas-fir), and determined the consequences for seasonal changes in photosynthetic capacity. The Douglas-fir site had soil with greater depth, finer texture and higher organic matter content than soil at the lodgepole pine site, all factors that increased the storage of soil moisture. While the measured xylem vulnerability curves were quite similar for the two species, Douglas-fir had lower average midday shoot water potentials than did lodgepole pine. This implied that lodgepole pine exhibited stronger stomatal control of transpiration than Douglas-fir, which helped to reduce the magnitude of the water potential gradient required to access water from drying soil. Stable hydrogen isotope measurements indicated that Douglas-fir increased the use of groundwater during mid-summer when precipitation inputs were low, while lodgepole pine did not. There was a greater reduction of photosynthetic carbon gain in lodgepole pine compared with Douglas-fir when the two tree species were exposed to seasonal declines in soil water content. The contrasting patterns of seasonal variation in photosynthetic capacity observed for the two species were a combined result of differences in soil characteristics at the separate sites and the inherent physiological differences between the species. PMID:22318220

  13. Variation in water potential, hydraulic characteristics and water source use in montane Douglas-fir and lodgepole pine trees in southwestern Alberta and consequences for seasonal changes in photosynthetic capacity.

    PubMed

    Andrews, Shilo F; Flanagan, Lawrence B; Sharp, Eric J; Cai, Tiebo

    2012-02-01

    Tree species response to climate change-induced shifts in the hydrological cycle depends on many physiological traits, particularly variation in water relations characteristics. We evaluated differences in shoot water potential, vulnerability of branches to reductions in hydraulic conductivity, and water source use between Pinus contorta Dougl. ex Loud. var. latifolia Engelm. (lodgepole pine) and Pseudotsuga menziesii (Mirb.) Franco (interior Douglas-fir), and determined the consequences for seasonal changes in photosynthetic capacity. The Douglas-fir site had soil with greater depth, finer texture and higher organic matter content than soil at the lodgepole pine site, all factors that increased the storage of soil moisture. While the measured xylem vulnerability curves were quite similar for the two species, Douglas-fir had lower average midday shoot water potentials than did lodgepole pine. This implied that lodgepole pine exhibited stronger stomatal control of transpiration than Douglas-fir, which helped to reduce the magnitude of the water potential gradient required to access water from drying soil. Stable hydrogen isotope measurements indicated that Douglas-fir increased the use of groundwater during mid-summer when precipitation inputs were low, while lodgepole pine did not. There was a greater reduction of photosynthetic carbon gain in lodgepole pine compared with Douglas-fir when the two tree species were exposed to seasonal declines in soil water content. The contrasting patterns of seasonal variation in photosynthetic capacity observed for the two species were a combined result of differences in soil characteristics at the separate sites and the inherent physiological differences between the species.

  14. Water properties in fern spores: sorption characteristics relating to water affinity, glassy states, and storage stability.

    PubMed

    Ballesteros, Daniel; Walters, Christina

    2007-01-01

    Ex situ conservation of ferns may be accomplished by maintaining the viability of stored spores for many years. Storage conditions that maximize spore longevity can be inferred from an understanding of the behaviour of water within fern spores. Water sorption properties were measured in spores of five homosporeous species of ferns and compared with properties of pollen, seeds, and fern leaf tissue. Isotherms were constructed at 5, 25, and 45 degrees C and analysed using different physicochemical models in order to quantify chemical affinity and heat (enthalpy) of sorption of water in fern spores. Fern spores hydrate slowly but dry rapidly at ambient relative humidity. Low Brunauer-Emmet-Teller monolayer values, few water-binding sites according to the D'Arcy-Watt model, and limited solute-solvent compatibility according to the Flory-Huggins model suggest that fern spores have low affinity for water. Despite the low water affinity, fern spores demonstrate relatively high values of sorption enthalpy (DeltaH(sorp)). Parameters associated with binding sites and DeltaH(sorp) decrease with increasing temperature, suggesting temperature- and hydration-dependent changes in volume of spore macromolecules. Collectively, these data may relate to the degree to which cellular structures within fern spores are stabilized during drying and cooling. Water sorption properties within fern spores suggest that storage at subfreezing temperatures will give longevities comparable with those achieved with seeds. However, the window of optimum water contents for fern spores is very narrow and much lower than that measured in seeds, making precise manipulation of water content imperative for achieving maximum longevity.

  15. Soil Water Characteristics of Cores from Low- and High-Centered Polygons, Barrow, Alaska, 2012

    DOE Data Explorer

    Graham, David; Moon, Ji-Won

    2016-08-22

    This dataset includes soil water characteristic curves for soil and permafrost in two representative frozen cores collected from a high-center polygon (HCP) and a low-center polygon (LCP) from the Barrow Environmental Observatory. Data include soil water content and soil water potential measured using the simple evaporation method for hydrological and biogeochemical simulations and experimental data analysis. Data can be used to generate a soil moisture characteristic curve, which can be fit to a variety of hydrological functions to infer critical parameters for soil physics. Considering the measured the soil water properties, the van Genuchten model predicted well the HCP, in contrast, the Kosugi model well fitted LCP which had more saturated condition.

  16. Impact of Providing Feed and/or Water on Performance, Physiology, and Behavior of Weaned Pigs during a 32-h Transport.

    PubMed

    Garcia, Arlene; Sutherland, Mhairi; Pirner, Glenna; Picinin, Guilherme; May, Matthew; Backus, Brittany; McGlone, John

    2016-01-01

    Transportation at weaning is a complex stressor made up of many factors, including withdrawal from feed and water, which can potentially negatively affect the health and welfare of pigs, especially those already experiencing weaning stress. The objective of this study was to evaluate the effect of weaning and extended transport durations (up to 32 h), with and without the provision of feed and/or water, on pig welfare. Treatment groups included: pigs neither weaned nor transported, control (CON); weaned pigs transported and provided with feed and water (T+); weaned pigs transported without feed and water (T-); weaned pigs transported with only feed (T+F); and weaned pigs transported with only water provided (TRAN+W). The effect of transport (with and without feed and/or water) on weaned pigs was assessed using behavior, performance, and physiology. After a 32-h transport period, pigs transported without water lost markedly more weight than those transported with water ( p < 0.01). Furthermore, the neutrophil to lymphocyte ratio was markedly higher in male pigs transported without water ( p < 0.05). Overall, transportation had a negative effect on pig well-being, especially when water was not provided. PMID:27153096

  17. Types and characteristics of drinking water for hydration in the elderly.

    PubMed

    Casado, Ángela; Ramos, Primitivo; Rodríguez, Jaime; Moreno, Norberto; Gil, Pedro

    2015-01-01

    The role of hydration in the maintenance of health is increasingly recognized. Hydration requirements vary for each person, depending on physical activity, environmental conditions, dietary patterns, alcohol intake, health problems, and age. Elderly individuals have higher risk of developing dehydration than adults. Diminution of liquid intake and increase in liquid losses are both involved in causing dehydration in the elderly. The water used for drinking is provided through regular public water supply and the official sanitary controls ensure their quality and hygiene, granting a range of variation for most of its physical and chemical characteristics, being sometimes these differences, though apparently small, responsible for some disorders in sensitive individuals. Hence, the advantages of using bottled water, either natural mineral water or spring water, are required by law to specify their composition, their major components, and other specific parameters. It is essential to take this into account to understand the diversity of indications and favorable effects on health that certain waters can offer.

  18. The influence of water temperature and accelerometer-determined fight intensity on physiological stress and reflex impairment of angled largemouth bass.

    PubMed

    Brownscombe, Jacob W; Marchand, Kelsey; Tisshaw, Kathryn; Fewster, Victoria; Groff, Olivia; Pichette, Melissa; Seed, Marian; Gutowsky, Lee F G; Wilson, Alexander D M; Cooke, Steven J

    2014-01-01

    Release of fish captured by recreational anglers is a common practice due to angler conservation ethics or compliance with fisheries regulations. As such, there is a need to understand the factors that influence mortality and sub-lethal impairments to ensure that catch-and-release angling is a sustainable practice. Longer angling times generally contribute to increased stress and mortality in fish such that reducing these times putatively reduces stress and improves survival. However, the relative importance of fight intensity (rather than simply duration) on fish condition is poorly understood. The objective of this research was to examine the effects of fight intensity on physiological stress and reflex impairment of largemouth bass (Micropterus salmoides). The largemouth bass were angled using conventional recreational fishing gear in May (water temperature ∼12°C) and June (∼22°C) of 2014 in Lake Opinicon, Ontario, Canada. Fight intensity was quantified using tri-axial accelerometer loggers mounted on the tips of fishing rods. Upon capture, reflex impairment measures were assessed, and fish were held for 1 h prior to blood sampling for measurement of physiological stress (blood glucose and lactate concentrations and pH). Physiological stress values showed a negative trend with fight duration and total fight intensity, but a positive trend with average fight intensity. Water temperature emerged as the most important predictor of the stress response in largemouth bass, while fight duration and intensity were not strong predictors. Reflex impairment was minimal, but higher reflex impairment scores were associated with elevated blood glucose. Overall, the findings of this study suggest that angling for largemouth bass at colder temperatures (<15°C) causes greater physiological stress than at warmer temperatures (>20°C). Based on our findings, we conclude that fight intensity is likely not to be a major driver of physiological stress in this species using

  19. A Characteristic Transmission Spectrum for WFC3 IR Water Hosting Exoplanet

    NASA Astrophysics Data System (ADS)

    Swain, Mark R.

    2015-12-01

    Using the 19 published Hubble/WFC3 IR exoplanet transmission spectra, we perform a meta-analysis of the spectral modulation due to water. Because of the heterogeneous nature of these data, in which spectral resolution, calibration approach, and observational method vary, we introduce a formalism to de-bias the estimates of spectral modulation. This analysis finds a characteristic transmission spectrum and examines trends for these water-hosting exoplanets.

  20. The Influence of topography on formation characteristics of hygroscopic and condensate water in Shapotou

    NASA Astrophysics Data System (ADS)

    Pan, Yanxia; Li, Xinrong; Hui, Rong; Zhao, Yang

    2016-04-01

    The formation characteristics of hygroscopic and condensate water for different topographic positions were observed using the PVC pipes manual weighing and CPM method in the typical mobile dunes fixed by straw checkerboard barriers in Shapotou. The results indicated that the formation amounts and duration of hygroscopic and condensate water show moderate spatial heterogeneity at the influence of topography. The formation amounts of hygroscopic and condensate water at different aspects conform to the classical convection model, in which the hygroscopic and condensate water amounts are highest at hollow, and windward aspect gets more water than leeward aspect, the hygroscopic and condensate water amounts at different aspects are expressed as: hollow>Western-faced aspect>Northern-faced aspect>hilltop>Southern-faced aspect>Eastern-faced aspect. The hygroscopic and condensate water amounts at different slope positions for every aspect are as follows: the foot of slope>middle slope>hilltop. A negatively linear correlation is got between slope angles and hygroscopic and condensate water amounts, hygroscopic and condensate water amounts decrease gradually along with the increase of slope angles, the amounts of hygroscopic and condensate water at the vertical aspect are only half of horizontal aspect, which indicated topography were important influence factors for the formation of the hygroscopic and condensate water in arid area.

  1. Work Capability and physiological effects predictive studies. 4: In He-O2 excursions to pressures of 400- 800- 1200- and 1600 feet of sea water

    NASA Technical Reports Server (NTRS)

    Lambertsen, C. J. (Editor); Gelfand, R. (Editor); Clark, J. M. (Editor); Fletcher, M. E. (Editor)

    1978-01-01

    Experiments which exposed men in chambers, breathing helium with oxygen, to progressive increases of pressure equivalent to 400-800-1200-1600 feet of sea water (fsw) were conducted. Rates of compression and exposure to stable high pressure. Goals included: 1) determination of the specific character and time course of onset of physiological and performance decrements during the intentionally rapid compressions, and determination of rates of adaptation on reaching stable elevated pressure; 2) investigation of accelerated methods for decompression in deep saturation excursion diving; and 3) determination of competence in practical work performed in water at pressures equivalent to the extreme diving depths of 1200 and 1600 fsw.

  2. Sprectroradiometric characteristics of inland water bodies infestated by Oscillatoria rubescens algae

    NASA Astrophysics Data System (ADS)

    Ciraolo, Giuseppe; La Loggia, Goffredo; Maltese, Antonino

    2010-10-01

    In December 2006 blooms of Oscillatoria rubescens were found in the reservoir Prizzi in Sicily. Oscillatoria is a genus of filamentous alga comprising approximately 6 species, between these the O. rubescens is sadly famous since this organism produces microcystins which are powerful hepatotoxins. Firstly found in Europe in 1825 on Geneva lake, recently (2006) those algae has been find out in Pozzillo, Nicoletti e Ancipa reservoirs (Enna Province), as well as in Prizzi (Palermo Province) and Garcia reservoirs (Trapani Province). Toxins produced by those bacteria (usually called microcystine LR-1 and LR-2) are highly toxic since they can activate oncogenes cells causing cancer pathologies on liver and gastrointestinal tract. Even if water treatment plants should ensure the provision of safe drinking water from surface waters contaminated with those toxic algae blooms, the contamination of reservoirs used for civil and agricultural supply highlights human health risks. International literature suggests a threshold value of 0.01 μgl-1 to avoid liver cancer using water coming from contaminated water bodies for a long period. Since O. rubescens activities is strongly related to phosphate and nitrogen compounds as well as to temperature and light transmission within water, the paper presents the comparison between optical properties of the water of an infested reservoir and those of a reservoir characterized by clear water. Field campaigns were carried out in February-March 2008 in order to quantify the spectral transparencies of two water bodies through the calculation of the diffuse attenuation coefficient, measuring underwater downwelling irradiance at different depths as well as water spectral reflectance. Results show that diffuse attenuation coefficient is reduced by approximately 15% reducing light penetration in the water column; coherently reflectance spectral signature generally decreases, exhibiting a characteristic peak around 703 nm not present in

  3. Analysis of drought characteristics for improved understanding of a water resource system

    NASA Astrophysics Data System (ADS)

    Lennard, A. T.; Macdonald, N.; Hooke, J.

    2014-09-01

    Droughts are a reoccurring feature of the UK climate; recent drought events (2004-2006 and 2010-2012) have highlighted the UK's continued vulnerability to this hazard. There is a need for further understanding of extreme events, particularly from a water resource perspective. A number of drought indices are available, which can help to improve our understanding of drought characteristics such as frequency, severity and duration. However, at present little of this is applied to water resource management in the water supply sector. Improved understanding of drought characteristics using indices can inform water resource management plans and enhance future drought resilience. This study applies the standardised precipitation index (SPI) to a series of rainfall records (1962-2012) across the water supply region of a single utility provider. Key droughts within this period are analysed to develop an understanding of the meteorological characteristics that lead to, exist during and terminate drought events. The results of this analysis highlight how drought severity and duration can vary across a small-scale water supply region, indicating that the spatial coherence of drought events cannot be assumed.

  4. Water-quality characteristics in the Black Hills area, South Dakota

    USGS Publications Warehouse

    Williamson, Joyce E.; Carter, Janet M.

    2001-01-01

    This report summarizes the water-quality characteristics of ground-water and surface-water in the Black Hills area. Differences in groundwater quality by aquifer and differences in surfacewater quality by water source are presented. Ground-water characteristics are discussed individually for each of the major aquifers in the Black Hills area, referred to herein as the Precambrian, Deadwood, Madison, Minnelusa, Minnekahta, and Inyan Kara aquifers. Characteristics for minor aquifers also are discussed briefly. Surface-water characteristics are discussed for hydrogeologic settings including headwater springs, crystalline core sites, artesian springs, and exterior sites. To characterize the water quality of aquifers and streams in the Black Hills area, data from the U.S. Geological Survey National Water Information System water-quality database were examined. This included samples collected as part of the Black Hills Hydrology Study as well as for other studies within the time frame of October 1, 1930, to September 30, 1998. Tables of individual results are not presented in this report, only summaries. Constituents summarized and discussed include physical properties, common ions, nutrients, trace elements, and radionuclides. Comparisons of concentration levels are made to drinking-water standards as well as beneficial-use and aquatic-life criteria. Ground water within the Black Hills and surrounding area generally is fresh and hard to very hard. Concentrations exceeding various Secondary and Maximum Contaminant Levels may affect the use of the water in some areas for many aquifers within the study area. Concentrations that exceed Secondary Maximum Contaminant Levels (SMCL's) generally affect the water only aesthetically. Radionuclide concentrations may be especially high in some of the major aquifers used within the study area and preclude the use of water in some areas. The sodiumadsorption ratio and specific conductance may affect irrigation use for some wells. High

  5. Determination of virtual water content of rice and spatial characteristics analysis in China

    NASA Astrophysics Data System (ADS)

    Zhang, L. J.; Yin, X. A.; Zhi, Y.; Yang, Z. F.

    2014-01-01

    China is a water-stressed country, and agriculture consumes the bulk of its water resources. Assessing the virtual water content (VWC) of crops is one important way to develop efficient water management measures to alleviate water resources conflicts among different sectors. In this research, the VWC of rice, as a major crop in China, was assessed and the spatial characteristics were analyzed. In addition to the calculation of green, blue and grey water - the direct water in VWC - the indirect water use of rice was also calculated, using the Input-Output model. The percentages of direct green, blue, grey and indirect water in the total VWC of rice in China were 43.8, 28.2, 27.6, and 0.4%. The total VWC of rice generally showed a three-tiered distribution, and decreased from southeast to northwest. The higher values of direct green water of rice were mainly concentrated in Southeast and Southwest China, while these values were relatively low in Northwest China and Inner Mongolia. The higher direct blue water values were mainly concentrated in the eastern and southern coastal regions and Northwest China, and low values were mainly concentrated in Southwest China. Grey water values were relatively high in Shanxi and Guangxi provinces and low in Northeast and Northwest China. The regions with high values for indirect water were randomly distributed but the regions with low values were mainly concentrated in Northwest and Southwest China. For the regions with relatively high total VWC the high values of blue water made the largest contribution, although for the country as a whole the direct green water is the most important contributor.

  6. Association of drinking-water source and use characteristics with urinary antimony concentrations.

    PubMed

    Makris, Konstantinos C; Andra, Syam S; Herrick, Lisa; Christophi, Costas A; Snyder, Shane A; Hauser, Russ

    2013-03-01

    Environmental factors, such as storage time, frequency of bottle reuse and temperature, have been shown to facilitate antimony (Sb) leaching from water- and food-packaging materials. The globally escalating consumption of water packaged in Sb-containing bottles, such as that of polyethylene terephthalate (PET), could increase human daily Sb doses. This study set out to investigate the relationship between drinking-water source, use characteristics, and urinary Sb concentrations (U-Sb) accompanied with survey responses of a healthy (n=35) Cypriot participant pool. One spot urine sample was collected during administration of questionnaire, while a second spot urine sample was collected from the same individual about 7 days later. Urinary and water Sb concentrations were measured with an inductively coupled plasma mass spectrometer. Survey responses showed that bottled water summed over various volumes and plastic types, such as polycarbonate and PET contributed to an average 61% of daily water consumption. Water sources such as tap, mobile stations (explained in a following section), and well water contributed to 24%, 14%, and 2% of an individual's daily water consumption pattern, respectively. Average daily potable water use of both bottled and tap water by individuals consisted of 65% drinking-water, while the remaining 35% was water used for preparing cold and hot beverages, such as, tea, coffee, and juices. A significant (P=0.02) association between per capita water consumption from PET bottles and urinary creatinine-unadjusted concentrations was observed, but this relationship did not remain after inclusion of covariates in a multivariate regression model. In the creatinine-adjusted regression model, only gender (female) was a significant (P<0.01) predictor of U-Sb, after adjusting for several covariates. It is proposed that consumption data collection on various water uses and sources among individuals could perhaps decrease the uncertainty associated with

  7. Association of drinking-water source and use characteristics with urinary antimony concentrations.

    PubMed

    Makris, Konstantinos C; Andra, Syam S; Herrick, Lisa; Christophi, Costas A; Snyder, Shane A; Hauser, Russ

    2013-03-01

    Environmental factors, such as storage time, frequency of bottle reuse and temperature, have been shown to facilitate antimony (Sb) leaching from water- and food-packaging materials. The globally escalating consumption of water packaged in Sb-containing bottles, such as that of polyethylene terephthalate (PET), could increase human daily Sb doses. This study set out to investigate the relationship between drinking-water source, use characteristics, and urinary Sb concentrations (U-Sb) accompanied with survey responses of a healthy (n=35) Cypriot participant pool. One spot urine sample was collected during administration of questionnaire, while a second spot urine sample was collected from the same individual about 7 days later. Urinary and water Sb concentrations were measured with an inductively coupled plasma mass spectrometer. Survey responses showed that bottled water summed over various volumes and plastic types, such as polycarbonate and PET contributed to an average 61% of daily water consumption. Water sources such as tap, mobile stations (explained in a following section), and well water contributed to 24%, 14%, and 2% of an individual's daily water consumption pattern, respectively. Average daily potable water use of both bottled and tap water by individuals consisted of 65% drinking-water, while the remaining 35% was water used for preparing cold and hot beverages, such as, tea, coffee, and juices. A significant (P=0.02) association between per capita water consumption from PET bottles and urinary creatinine-unadjusted concentrations was observed, but this relationship did not remain after inclusion of covariates in a multivariate regression model. In the creatinine-adjusted regression model, only gender (female) was a significant (P<0.01) predictor of U-Sb, after adjusting for several covariates. It is proposed that consumption data collection on various water uses and sources among individuals could perhaps decrease the uncertainty associated with

  8. Monitoring water stress and fruit quality in an orange orchard under regulated deficit irrigation using narrow-band structural and physiological remote sensing indices

    NASA Astrophysics Data System (ADS)

    Stagakis, S.; González-Dugo, V.; Cid, P.; Guillén-Climent, M. L.; Zarco-Tejada, P. J.

    2012-07-01

    This paper deals with the monitoring of water status and the assessment of the effect of stress on citrus fruit quality using structural and physiological remote sensing indices. Four flights were conducted over a citrus orchard in 2009 using an unmanned aerial vehicle (UAV) carrying a multispectral camera with six narrow spectral bands in the visible and near infrared. Physiological indices such as the Photochemical Reflectance Index (PRI570), a new structurally robust PRI formulation that uses the 515 nm as the reference band (PRI515), and a chlorophyll ratio (R700/R670) were compared against the Normalized Difference Vegetation Index (NDVI), Renormalized Difference Vegetation Index (RDVI) and Modified Triangular Vegetation Index (MTVI) canopy structural indices for their performance in tracking water status and the effects of sustained water stress on fruit quality at harvest. The irrigation setup in the commercial orchard was compared against a treatment scheduled to satisfy full requirements (based on estimated crop evapotranspiration) using two regulated deficit irrigation (RDI) strategies. The water status of the trees throughout the experiment was monitored with frequent field measurements of stem water potential (Ψx), while titratable acidity (TA) and total soluble solids (TSS) were measured at harvest on selected trees from each irrigation treatment. The high spatial resolution of the multispectral imagery (30 cm pixel size) enabled identification of pure tree crown components, extracting the tree reflectance from shaded, sunlit and aggregated pixels. The physiological and structural indices were then calculated from each tree at the following levels: (i) pure sunlit tree crown, (ii) entire crown, aggregating the within-crown shadows, and (iii) simulating a lower resolution pixel, including tree crown, sunlit and shaded soil pixels. The resulting analysis demonstrated that both PRI formulations were able to track water status, except when water stress

  9. Understanding how the leaf physiology of mangrove plants differs from fresh water plants: a fundamental step to use cellulose as a proxy for sea level rise

    NASA Astrophysics Data System (ADS)

    Ellsworth, P.; Sternberg, L. O.

    2010-12-01

    We studied the leaf water isotopic enrichment pattern of mangrove (halophytes) and hammock (glycophytes) plants as an attempt to explain why the δ18O of stem cellulose from mangrove and hammock species have no relationship with the δ18O of source water. A better understanding of leaf physiology of mangroves and its effect on the δ18O of stem cellulose is the first step in the process of developing an isotopic proxy for sea-level rise. Seawater is enriched in 18O relative to freshwater and this difference should be recorded in stem cellulose during its synthesis. Therefore, an enrichment in the oxygen isotope ratios of cellulose would reflect an increase in sea water levels. However, only ~40% of the 18O signal of stem cellulose comes from source water, the other ~60% comes from leaf water. Mangrove and hammock plants respond to environment conditions differently, which calls for a better understanding of leaf physiology and the ability to tease leaf physiolocal effects apart from the source water signal. We hypothesized that it’s likely that mangrove plants, having a greater proportion of water traveling simplastically, would have a longer water pathway from the xylem to the stomatal pore than hammock plants. According to the Peclet effect, this would cause lower isotopic enrichment of leaf water in mangroves compared to those of hammock species. This would explain previous measurements where δ18O of stem cellulose of mangrove was not as enriched as the expected. To test our hypothesis, a transect was selected across the 2 vegetation types (mangroves and hammocks). The parameters measured where: transpiration, temperature of the leaf, ambient temperature, relative humidity, δ18O of vapor, δ18O of stem water and δ18O of leaf water. With those parameters we calculated the effective length of the water pathway from the xylem to the stomatal pore. The results confirmed our hypothesis that mangrove leaves have a longer water pathway from the xylem to the

  10. Multi-Elements in Waters and Sediments of Shallow Lakes: Relationships with Water, Sediment, and Watershed Characteristics

    PubMed Central

    Jacob, Donna L.; Hanson, Mark A.; Herwig, Brian R.; Bowe, Shane E.; Otte, Marinus L.

    2015-01-01

    We measured concentrations of multiple elements, including rare earth elements, in waters and sediments of 38 shallow lakes of varying turbidity and macrophyte cover in the Prairie Parkland (PP) and Laurentian Mixed Forest (LMF) provinces of Minnesota. PP shallow lakes had higher element concentrations in waters and sediments compared to LMF sites. Redundancy analysis indicated that a combination of site- and watershed-scale features explained a large proportion of among-lake variability in element concentrations in lake water and sediments. Percent woodland cover in watersheds, turbidity, open water area, and macrophyte cover collectively explained 65.2 % of variation in element concentrations in lake waters. Sediment fraction smaller than 63 µm, percent woodland in watersheds, open water area, and sediment organic matter collectively explained 64.2 % of variation in element concentrations in lake sediments. In contrast to earlier work on shallow lakes, our results showed the extent to which multiple elements in shallow lake waters and sediments were influenced by a combination of variables including sediment characteristics, lake morphology, and percent land cover in watersheds. These results are informative because they help illustrate the extent of functional connectivity between shallow lakes and adjacent lands within these lake watersheds. PMID:26074657

  11. [Effects of soil surface mulching on the growth and physiological characteristics of grafted and non-grafted cucumbers in solar greenhouse].

    PubMed

    Zhai, Sheng; Liang, Yinli; Wang, Juyuan; Dai, Quanhou; Du, Sheni; You, Haixia; Chen, Jiarui

    2006-06-01

    This paper studied the effects of wheat straw mulching, plastic film mulching, and wheat straw plus plastic film mulching on the growth and physiological characteristics of grafted and non-grafted Cucumis sativus in solar greenhouse. The results showed that compared with the control, the plant height, stem diameter, photosynthetic rate, and root vitality of grafted C. sativus under wheat straw plus plastic film mulching, plastic film mulching, and wheat straw mulching were increased by 91, 71 and 57 cm, 0.127, 0.086 and 0.111 cm, 2.63, 2.08 and 1.36 micromol x m(-2) x s(-1), and 0.98, 0.48 and 0.8 mg TTC x g(-1) FW, respectively, while non-grafted C. sativus had a less increment. The chlorophyll content of grafted C. sativus under wheat straw plus plastic film mulching and wheat straw mulching was 1.8% and 3.15% higher than the control, respectively, but that under plastic film mulching was 3.8% less than the control. Soil surface mulching increased the dry weight per plant, early yield, and total yield. Under wheat straw plus plastic film mulching, plastic film mulching, and wheat straw mulching, the individual yield of grafted C. sativus was 16%, 5.3% and 3.4% higher than that of non-grafted C. sativus, respectively.

  12. Earthworm eco-physiological characteristics and quantification of earthworm feeding in vermifiltration system for sewage sludge stabilization using stable isotopic natural abundance.

    PubMed

    Li, Xiaowei; Xing, Meiyan; Yang, Jian; Dai, Xiaohu

    2014-07-15

    Previous studies showed that the presence of earthworm improves treatment performance of vermifilter (VF) for sewage sludge stabilization, but earthworm eco-physiological characteristics and effects in VF were not fully investigated. In this study, earthworm population, enzymatic activity, gut microbial community and stable isotopic abundance were investigated in the VF. Results showed that biomass, average weight, number and alkaline phosphatase activity of the earthworms tended to decrease, while protein content and activities of peroxidase and catalase had an increasing tendency as the VF depth. Earthworm gut microbial communities were dominated by Gammaproteobacteria, and the percentages arrived to 76-92% of the microbial species detected. (15)N and (13)C natural abundance of the earthworms decreased with operation time, and increased as the VF depth. Quantitative analysis using δ(15)N showed that earthworm feeding and earthworm-microorganism interaction were responsible for approximately 21% and 79%, respectively, of the enhanced volatile suspended solid reduction due to the presence of earthworm. The finding provides a quantitative insight into how earthworms influence on sewage sludge stabilization in vermifiltration system.

  13. [Effects of high- and low temperature stress on the leaf PSII functions and physiological characteristics of tree peony (Paeonia suffruticosa cv. 'Roufurong')].

    PubMed

    Liu, Chun-Ying; Chen, Da-Yin; Gai, Shu-Peng; Zhang, Yu-Xi; Zheng, Guo-Sheng

    2012-01-01

    Taking the detached leaves of tree peony (Paeonia suffruticosa cv. 'Roufurong') as test materials, this paper studied the effects of high temperature (40 degrees C) and low temperature (15 degrees C) stresses on the PS II functions and physiological characteristics of peony leaves under strong light intensity (1400 micromol x m(-2) x s(-1)), with 25 degrees C as the control. With the increasing time of high- and low temperature stress, the maximal photochemical efficiency (Fv/Fm), actual quantum yield of photosystem II (Phi(PS II)) , and efficiency of excitation capture of open PS II center (Fv'/Fm') all decreased continuously. After recovered in the dark for 4 hours, the Fv/Fm in treatments 15 degrees C and 25 degrees C quickly recovered, but that in treatment 40 degrees C only recovered to 75.5% of non-treatment, even if the leaves were treated in the dark for 15 hours. At 40 degrees C, the balance of excited energy between PS I and PS II under strong light intensity was perturbed seriously. Treatment 40 degrees C inhibited the superoxide dismutase (SOD) activity, enhanced the production of O2-, H2O2, and MDA, and reduced the contents of chlorophyll and soluble protein. This study revealed that strong light combined with high temperature impaired the photosynthetic apparatus of the tree peony irreversibly, whereas strong light plus low temperature had weaker impact.

  14. Influence of carvacrol and thymol on the physiological attributes, enterotoxin production and surface characteristics of Staphylococcus aureus strains isolated from foods

    PubMed Central

    Souza, E.L.; Oliveira, C.E.V.; Stamford, T.L.M.; Conceição, M.L.; Neto, N.J. Gomes

    2013-01-01

    This study evaluated the influence of the phenolic compounds carvacrol (CAR) and thymol (THY) on some physiological characteristics and on the modulation of the secretion of some staphylococcal virulence factors, that is, coagulase and enterotoxin. This study also investigated possible mechanisms for the establishment of the anti-staphylococcal activity of these compounds. Sublethal concentrations (0.3 and 0.15 μL/mL) of CAR and THY inhibited the activity of the enzymes coagulase and lipase and led to a decrease in salt tolerance. At the tested sublethal concentrations, both CAR and THY led to a total suppression of enterotoxin production. The loss of a 260-nm-absorbing material and an efflux of potassium ions occurred immediately after the addition of CAR and THY at 0.6 and 1.2 μL/mL and increased up to 120 min of exposure. Electron microscopy of cells exposed to CAR and THY (0.6 μL/mL) revealed that individual cells appeared to be deformed, with projections of cellular material. The observations of leakage of cellular material and an altered cell surface suggest that gross damage to a cell’s cytoplasmic membrane, which results in a disruption in protein secretion, could be responsible for the anti-staphylococcal properties of CAR and THY. PMID:24159280

  15. Hydrochemical characteristics of mine waters from abandoned mining sites in Serbia and their impact on surface water quality.

    PubMed

    Atanacković, Nebojša; Dragišić, Veselin; Stojković, Jana; Papić, Petar; Zivanović, Vladimir

    2013-11-01

    Upon completion of exploration and extraction of mineral resources, many mining sites have been abandoned without previously putting environmental protection measures in place. As a consequence, mine waters originating from such sites are discharged freely into surface water. Regional scale analyses were conducted to determine the hydrochemical characteristics of mine waters from abandoned sites featuring metal (Cu, Pb-Zn, Au, Fe, Sb, Mo, Bi, Hg) deposits, non-metallic minerals (coal, Mg, F, B) and uranium. The study included 80 mine water samples from 59 abandoned mining sites. Their cation composition was dominated by Ca2+, while the most common anions were found to be SO4(2-) and HCO3-. Strong correlations were established between the pH level and metal (Fe, Mn, Zn, Cu) concentrations in the mine waters. Hierarchical cluster analysis was applied to parameters generally indicative of pollution, such as pH, TDS, SO4(2-), Fe total, and As total. Following this approach, mine water samples were grouped into three main clusters and six subclusters, depending on their potential environmental impact. Principal component analysis was used to group together variables that share the same variance. The extracted principal components indicated that sulfide oxidation and weathering of silicate and carbonate rocks were the primary processes, while pH buffering, adsorption and ion exchange were secondary drivers of the chemical composition of the analyzed mine waters. Surface waters, which received the mine waters, were examined. Analysis showed increases of sulfate and metal concentrations and general degradation of surface water quality.

  16. Study of distribution and characteristics of the time average of pressure of a water cushion pool

    NASA Astrophysics Data System (ADS)

    Guo, Y. H.; Fu, J. F.

    2016-08-01

    When a dam discharges flood water, the plunging flow with greater kinetic energy, will scour the riverbed, resulting in erosion damage. In order to improve the anti-erosion capacity of a riverbed, the cushion pool created. This paper is based on turbulent jet theoryto deduce the semi-empirical formula of the time average of pressure in the impinging portion of the cushion pool. Additionally, MATLAB numerical is used to conduct a simulation analysis according to turbulent jet energy and watercushion depth when water floods into the water cushion pool, to determine the regularities of distribution and related characteristics.

  17. Enthalpy characteristics of sodium phenylalaninate solvation in mixtures of water with ethanol at 298 K

    NASA Astrophysics Data System (ADS)

    Vandyshev, V. N.; Litova, N. A.

    2013-02-01

    The heat effects of mixing for aqueous solutions of sodium phenylalaninate (NaPheAla) with mixtures of water and ethanol are measured by calorimetry at 298.15 K. The standard enthalpies of transfer of a stoichiometric mixture of ions, and of an organic ion of α-PheAla- from water to water-alcohol mixtures are calculated. The enthalpy coefficients of binary and ternary ion-alcohol interactions are calculated using the McMillan-Mayer theory. The obtained enthalpy characteristics are compared with previously studied systems containing synthetic β- and natural α-alanine.

  18. Regional distribution of longevity population and chemical characteristics of natural water in Xinjiang, China.

    PubMed

    Liu, Yong-Lin; Luo, Kun-Li; Lin, Xiao-Xu; Gao, Xing; Ni, Run-Xiang; Wang, Shao-Bin; Tian, Xing-Lei

    2014-03-01

    Xinjiang Province, China is recognized for the longevity of its inhabitants. To study the temporal and spatial variation of longevity region and chemical characteristics of natural water of longevity region in Xinjiang, three population censuses on county-level and 51 natural water samples from Hotan Prefecture, Xinjiang were collected and analyzed. 103 natural water samples were collected from the public papers. Population statistics on county-level showed that the number of centenarians per 100,000 inhabitants (OC) in Southern Xinjiang was 7.4(year 1990), 4.9(year 2000) and 2.1 times (year 2010) more than that of Northern Xinjiang, respectively. And distribution of the longevity index (LI%), centenarity index (CI%) and number of centenarians per 10,000 over 65 year-old subjects (UC) on county-level decreased from south to north. Natural water in Northern Xinjiang was mainly fresh soft water, and it was mainly fresh hard water and brackish hard water in Southern Xinjiang. Water quality of natural water in Northern Xinjiang was superior compare to that of Southern Xinjiang, while number of centenarians 65 year-old & over per 10,000 subjects in Northern Xinjiang were less than that of Southern Xinjiang before 2010. The research indicates that keeping on drinking water with high total hardness (TH) and Mg/Ca ratio might be good for the health.

  19. Water-soluble characteristics of chlorine in char derived from municipal solid wastes.

    PubMed

    Hwang, I H; Matsuto, T; Tanaka, N

    2006-01-01

    Chlorine in char derived from municipal solid waste (MSW) was characterized and quantified based on its water solubility: easily water-soluble, hardly water-soluble, and non-water-soluble chlorine. For that, a four-cycle process of water-washing, heating or carbonation were carried out. In order to confirm the characteristics of non-water-soluble chlorine, additional thermal treatment and an alkali-acid washing process were applied to washed char. It was found that a large particle size of char (0.5-1.0 mm) significantly contributed to the amount of non-water-soluble chlorine. Pulverization and HNO3-HF digestion were performed to identify a factor to interfere chlorine release from char with a large particle size. Pulverization was proven ineffective for release of non-water-soluble chlorine, whereas approximately 32% of non-water-soluble chlorine was extracted by HNO3-HF digestion. Therefore, the presence of non-water-soluble chlorine is likely to originate from its chemical property rather than simply from its physical one.

  20. The importance of lake-specific characteristics for water quality across the continental United States.

    PubMed

    Read, Emily K; Patil, Vijay P; Oliver, Samantha K; Hetherington, Amy L; Brentrup, Jennifer A; Zwart, Jacob A; Winters, Kirsten M; Corman, Jessica R; Nodine, Emily R; Woolway, R Iestyn; Dugan, Hilary A; Jaimes, Aline; Santoso, Arianto B; Hong, Grace S; Winslow, Luke A; Hanson, Paul C; Weathers, Kathleen C

    2015-06-01

    Lake water quality is affected by local and regional drivers, including lake physical characteristics, hydrology, landscape position, land cover, land use, geology, and climate. Here, we demonstrate the utility of hypothesis testing within the landscape limnology framework using a random forest algorithm on a national-scale, spatially explicit data set, the United States Environmental Protection Agency's 2007 National Lakes Assessment. For 1026 lakes, we tested the relative importance of water quality drivers across spatial scales, the importance of hydrologic connectivity in mediating water quality drivers, and how the importance of both spatial scale and connectivity differ across response variables for five important in-lake water quality metrics (total phosphorus, total nitrogen, dissolved organic carbon, turbidity, and conductivity). By modeling the effect of water quality predictors at different spatial scales, we found that lake-specific characteristics (e.g., depth, sediment area-to-volume ratio) were important for explaining water quality (54-60% variance explained), and that regionalization schemes were much less effective than lake specific metrics (28-39% variance explained). Basin-scale land use and land cover explained between 45-62% of variance, and forest cover and agricultural land uses were among the most important basin-scale predictors. Water quality drivers did not operate independently; in some cases, hydrologic connectivity (the presence of upstream surface water features) mediated the effect of regional-scale drivers. For example, for water quality in lakes with upstream lakes, regional classification schemes were much less effective predictors than lake-specific variables, in contrast to lakes with no upstream lakes or with no surface inflows. At the scale of the continental United States, conductivity was explained by drivers operating at larger spatial scales than for other water quality responses. The current regulatory practice of using

  1. CONNECTING WATERSHED CHARACTERISTICS TO NUTRIENT REGIME FROM HEADWATERS TO RECEIVING WATERS IN THE LAURENTIAL GREAT LAKES

    EPA Science Inventory

    We are evaluating the influence of position along the tributary-coastal wetland-lake continuum on the expression of watershed characteristics in the water quality of Great Lakes (GL) coastal ecosystems as part of an EPA study focused on determining stressor-response relationships...

  2. Water Transport Characteristics of Gas Diffusion Layer in a PEM Fuel Cell

    SciTech Connect

    Damle, Ashok S; Cole, J Vernon

    2008-11-01

    A presentation addressing the following: Water transport in PEM Fuel Cells - a DoE Project 1. Gas Diffusion Layer--Role and Characteristics 2. Capillary Pressure Determinations of GDL Media 3. Gas Permeability Measurements of GDL Media 4. Conclusions and Future Activities

  3. Fetal cardiovascular physiology.

    PubMed

    Rychik, J

    2004-01-01

    The cardiovascular system of the fetus is physiologically different than the adult, mature system. Unique characteristics of the myocardium and specific channels of blood flow differentitate the physiology of the fetus from the newborn. Conditions of increased preload and afterload in the fetus, such as sacrococcygeal teratoma and twin-twin transfusion syndrome, result in unique and complex pathophysiological states. Echocardiography has improved our understanding of human fetal cadiovasvular physiology in the normal and diseased states, and has expanded our capability to more effectively treat these disease processes.

  4. Comparison of selected cultural, physical, and water-quality characteristics of lakes in Washington

    USGS Publications Warehouse

    Bortleson, Gilbert Carl; Dion, N.P.

    1979-01-01

    The report presents comparisons and a graphical overview of the relative magnitude and regional and statewide distribution of 19 selected cultural, physical, and water-quality characteristics measured in a reconnaissance study of several hundred lakes in Washington. Statewide, mean depth of almost one-fourth of the lakes is shallow (2.0 meters or less), and only 7 percent of the lakes have mean depths greater than 20 meters. About one-third of the lakes had Secchi-disc readings of 2.0 meters or less, a value often considered characteristic of eutrophic lakes. The poorest water clarity was observed in the Columbia Plateau, where 68 percent of the lakes had Secchi-disc readings of less than 2.0 meters. More than one-third of the lakes in the State had total phosphorus concentrations that exceeded 30 micrograms per liter, a concentration that is often considered characteristic of eutrophic lakes. (Woodard-USGS)

  5. [Retrieve of red tide distributions from MODIS data based on the characteristics of water spectrum].

    PubMed

    Qiu, Zhong-Feng; Cui, Ting-Wei; He, Yi-Jun

    2011-08-01

    After comparing the spectral differences between red tide water and normal water, we developed a method to retrieve red tide distributions from MODIS data based on the characteristics of red tide water spectrum. The authors used the 119 series of in situ observations to validate the method and found that only one observation has not been detected correctly. The authors then applied this method to MODIS data on April 4, 2005. In the research areas three locations of red tide water were apparently detected with the total areas about 2 000 km2. The retrieved red tide distributions are in good agreement with the distributions of high chlorophyll a concentrations. The research suggests that the method is available to eliminating the influence of suspended sediments and can be used to retrieve the locations and areas of red tide water.

  6. Physiological Waterfalls

    ERIC Educational Resources Information Center

    Leith, David E.

    1976-01-01

    Provides background information, defining areas within organ systems where physiological waterfalls exist. Describes pressure-flow relationships of elastic tubes (blood vessels, airways, renal tubules, various ducts). (CS)

  7. [Physiological characteristics of Pinus densiflora var. zhangwuensis and Pinus sylvestris var. mongolica seedlings on sandy lands under salt-alkali stresses].

    PubMed

    Meng, Peng; Li, Yu-Ling; Zhang, Bai-xi

    2013-02-01

    For the popularization of Pinus densiflora var. zhangwuensis, a new afforestation tree species on the desertified and salinized-alkalized lands in Northern China, and to evaluate the salinity-alkalinity tolerance of the tree species and to better understand the tolerance mechanisms, a pot experiment with 4-year old P. densiflora var. zhangwuensis and P. sylvestris var. mongolica was conducted to study their seedlings growth and physiological and biochemical indices under the effects of three types salt (NaCl, Na2CO3, and NaHCO3 ) stresses and of alkali (NaOH) stress. Under the salt-alkali stresses, the injury level of P. densiflora var. zhangwuensis was lower, and the root tolerance index was higher. The leaf catalase (CAT) activity increased significantly by 22. 6 times at the most, as compared with the control; the leaf malondialdehyde (MDA) content had no significant increase; the leaf chlorophyll (Chl) content had a smaller decrement; and the leaf water content (LWC) increased slightly. P. sylvestris var. mongolica responded differently to the salt-alkali stresses. Its leaf CAT activity had less change, MDA content increased significantly, Chl content had significant decrease, and LWC decreased slightly. It was suggested that P. densi-flora var. zhangwuensis had a greater salinity-alkalinity tolerance than P. sylvestris var. mongolica. The higher iron concentration in P. densiflora var. zhangwuensis needles enhanced the CAT activity and Chl content, whereas the higher concentrations of zinc and copper were associated with the stronger salinity-alkalinity tolerance. PMID:23705379