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At least 37 records · Page 2Linked to original sources

Serologic types and physiologic characteristics of 46 avian Pasteurella anatipestifer cultures.

Forty-six strains of Pasteurella anatipestifer isolated from different avian species were examined to determine their serologic types and physiologic characteristics. Serologic types were determined by a gel-diffusion precipitin test. Antigens from 39 field isolates reacted with antisera prepared from seven P. anatipestifer reference strains representing serotypes 1, 2, 4, 6, and 7. Antigens from five isolates did not react and could not be typed with available reagents. Gel precipitin reactions involving serotype 1 (43.6%) and serotype 2 (25.6%) were the most prevalent. Generally, the physiologic characteristics from 40 tests were typical for P. anatipestifer, and variations were observed among the strains in urease production, hemolysin production, litmus milk reaction, and gelatin liquefaction.

Animals↗

[Effects of shading on squash seedlings' morphological and photosynthetic physiological characteristics].

The study of squash seedlings' morphological and photosynthetic physiological characteristics under different shading showed that under 60% light transmittance, their relative growth rate, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (EVAP), water use efficiency (WUE), saturation steam pressure (MBR), apparent quantum yield of photosynthesis (AQY), and chlorophyll contents were higher, while the intercellular CO2 concentration (Ci) was lower, compared with those under 20% light transmittance and CK. The seedlings under 60% light transmittance had a higher light saturation point (1 125 micromol x m(-2) x s(-1)) but a lower light compensation point (15.2 micromol x m(-2) s(-1)). Squash seedlings under lower light intensity could endure lower concentration of CO2, while those under higher light intensity could endure higher concentration of CO2. Under 60% light transmittance, the malondialdehyde (MDA) and praline (Pro) contents were the lowest, while the peroxidase (POD) and catalase (CAT) activities were the highest.

Cucurbita↗

A review of research on genetic variation in physiological characteristics related to performance in dairy cattle.

Genetic influence on physiological characteristics ranges from single gene effects on amino acid substitutions in alternative forms of proteins to quantitative genetic effects on the amounts of enzymes and hormones. The number of loci involved in the control of quantitative variation in physiologically important substances is not known. A number of marker genes that affect blood antigens, serum and milk proteins, and enzymes have been identified in dairy cattle. However, relatively little is known about genetic effects on quantitative physiological traits in dairy cattle. Much more is known about the genetic control of hormones in laboratory animals. About 25% of the variation in milk production of dairy cows results from genetic differences. We need more studies of genetic influences on the various physiological and biochemical processes involved in the secretion of milk to reveal the mechanisms by which genetics influences the quantity and quality of milk produced by individual cows.

Animals↗

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

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.

Culture Media↗

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

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).

Carbon↗

Cultural, morphological, and physiological characteristics of Thermomonospora fusca (strain 190Th).

The cultural, morphological, and physiological properties of Thermomonospora fusca (strain 190Th) are described. Its physiological properties show that this species is primarily a carbohydrate-degrading actinomycete which can use a wide range of plant sugars and polymeric carbohydrates as sources of carbon and energy. The culture does not use proteins or amino acids for carbon and energy, or as a nitrogen source. A few organic acids are utilized. Ammonia is the preferred nitrogen source. The culture has trace nutrient requirements which include biotin and an undetermined number of amino acids. These and other physiological characteristics are discussed in relation to the roles that T. fusca carries out as a saprophytic bacterium in nature. Its cultural and morphological properties are discussed in relation to the taxonomic status of this species in the literature.

Amino Acids↗

Biochemical and physiological characteristics of Yarrowia lipolytica strains in relation to isolation source.

The physiological characteristics and fatty acid composition of 40 strains of Yarrowia lipolytica isolated from irradiated poultry meat, commercial chilled foods, the superficial water of lagoons of an Italian river delta, and commercial light butter were compared. Discriminant analysis of the results permitted the 40 strains to be classified into four groups according to their isolation source. The lag phase length at 3, 5, and 7 degrees C, the proteolytic and lipolytic activities, and the growth on sorbitol, gluconate, and N-acetylglucosamine, as well as the relative percentages of C12:0, C15:0, C17:1, C18:1, C18:2, the unsaturation level, and the percentage of total odd chain fatty acids were the characteristics exhibiting the highest discriminatory power. These results indicate that the isolates are well adapted and significant biochemical characteristics may account for the success of individual strains in their original habitat.

Fatty Acids↗

Anthropometric and physiological characteristics of junior elite volleyball players.

OBJECTIVES: To investigate the anthropometric and physiological characteristics of junior elite volleyball players. METHOD: Twenty five national level volleyball players (mean (SD) age 17.5 (0.5) years) were assessed on a number of physiological and anthropometric variables. Somatotype was assessed using the Heath-Carter method, body composition (% body fat, % muscle mass) was assessed using surface anthropometry, leg strength was assessed using a leg and back dynamometer, low back and hamstring flexibility was assessed using the sit and reach test, and the vertical jump was used as a measure of lower body power. Maximal oxygen uptake was predicted using the 20 m multistage fitness test. RESULTS: Setters were more ectomorphic (p<0.05) and less mesomorphic (p<0.01) than centres. Mean (SD) of somatotype (endomorphy, mesomorphy, ectomorphy) for setters and centres was 2.6 (0.9), 1.9 (1.1), 5.3 (1.2) and 2.2 (0.8), 3.9 (1.1), 3.6 (0.7) respectively. Hitters had significantly greater low back and hamstring flexibility than opposites. Mean (SD) for sit and reach was 19.3 (8.3) cm for opposites and 37 (10.7) cm for hitters. There were no other significant differences in physiological and anthropometric variables across playing positions (all p>0.05). CONCLUSION: Setters tend to be endomorphic ectomorphs, hitters and opposites tend to be balanced ectomorphs, whereas centres tend to be ectomorphic mesomorphs. These results indicate the need for sports scientists and conditioning professionals to take the body type of volleyball players into account when designing individualised position specific training programmes.

Adolescent↗

Physiological characteristics of junior and senior rugby league players.

OBJECTIVES: To investigate the physiological characteristics of subelite junior and senior rugby league players and establish performance standards for these athletes. METHODS: A total of 159 junior (under 16, 15, 14, and 13, n = 88) and senior (first grade, second grade, and under 19, n = 71) rugby league players (forwards, n = 80, backs, n = 79), competing at a subelite level, underwent measurements of body mass, muscular power (vertical jump), speed (10 m, 20 m, and 40 m sprint), agility (Illinois agility run), and estimated maximal aerobic power (multistage fitness test). Data were also collected on match and training frequency and playing experience. RESULTS: There was a significant effect (p<0.05) of age and playing level on playing experience, body mass, muscular power, speed, agility, and estimated maximal aerobic power, with the physiological capacities of players increasing as the playing level increased. Forwards were heavier than backs for all junior and senior teams. Forwards and backs had similar estimated maximal aerobic power, except for under 16 players, for whom significant (p<0.05) differences were detected (mean (95% confidence intervals) 42.9 (40.1 to 45.7) v 49.5 (46.4 to 52.6) ml/kg/min for forwards and backs respectively). Scores for speed, muscular power, and agility were not significantly different between forwards and backs for any of the junior or senior teams. CONCLUSIONS: The results show that there is a progressive improvement in the physiological capacities of rugby league players as the playing level increases. These findings provide normative data and performance standards for subelite junior and senior rugby league players. Further studies on the sociological, physical, psychological, and personal predictors of talent in rugby league are warranted.

Adolescent↗

Body composition and physiological characteristics of law enforcement officers.

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.

Adult↗

DNA sequence similarity, cell wall mannans and physiological characteristics in some strains of Candida utilis, Hansenula jadinii and Hansenula petersonii.

The physiological characteristics, proton magnetic resonance spectra of cell wall mannans, DNA base composition and DNA sequence similarity of some strains of Candida utilis, Hansenula jadinii and Hansenula petersonii were examined. It was found that C. utilis was not distinguishable from H. jadinii by any of these criteria. These findings show the close genetic relationship between C. utilis and its perfect form H. jadinii. In contrast, H. petersonii was found to differ from C. utilis and H. jadinii on account of insignificant DNA reassociation as well as a number of other properties.

Ascomycota↗

Reproducibility and physiological characteristics of 24-hour ambulatory esophangeal manometry/pH-metry.

OBJECTIVES: To assess the reproducibility and physiological characteristics of ambulatory esophageal manometry/pH-metry. METHODS: Ten healthy volunteers were studied on two separate occasions (2 wk apart) using the Synectics Microdigitrapper System. The pH recording failed in one subject; thus, pH data were analyzed in nine, and motility measurements in all 10 subjects. RESULTS: A high degree of reproducibility was established for the five pH and seven manometry variables assessed. Using the paired t test and Wilcoxon signed rank test to compare the two sets of data, all p values were >0.05. Narrow 95% confidence intervals containing the zero measures were also obtained on the differences of the data from both sessions for all variables. Better correlation coefficients were obtained for the motility parameters than for the pH parameters. As would be expected, reflux occurred more often in the upright than in the supine position. Furthermore, esophageal contractions were of higher amplitude and longer duration in the distal esophagus, and the frequency of propulsive contractions sequences was higher during meals and in the upright position than in the supine position. CONCLUSIONS: This study demonstrates the reproducibility of ambulatory esophageal manometry/pH-metry, suggesting that this technology may be useful in assessing the effect of pharmacological intervention on esophageal motor function.

Adult↗

[Physiological characteristics of pneumococci].

The physiological activity of pneumococci under different physico-chemical conditions of deep cultivation in a liquid culture medium has been studied. The culture has been shown to achieve its maximum physiological activity under the conditions of neutral pHn-7.0) and the minimum content of dissolved oxygen in the medium. The addition of 5-11% of CO2 to the gas mixture has a positive effect on cultivation, the cultures thus obtained possessing high virulence and pronounced capsules.

Animals↗

Physiological characteristics of skeletal muscles of dogs and cats.

Our purpose was to determine if physiological characteristics of skeletal muscles of dogs and cats are related to their histochemical and biochemical characteristics. Maximum oxygen consumption (VO2max) and blood flow (Q) at VO2max were determined for in situ muscles of dogs and cats. Compared to cat muscles, dog muscles per unit mass had higher succinate oxidase activities, VO2max's, and Q's at VO2max's. There are positive relationships between Q at VO2max and VO2max and between VO2max and succinate oxidase activity. The higher VO2max's and succinate oxidase activities of dog muscles are consistent with the presence in these muscles of only slow-twitch fatique-resistant fibers and fast-twitch fatique-resistant fibers, whereas up to 50% of the fibers found in cat muscles are fast-twitch fatiqable. Capillary-to-fiber ratios are 2.40-2.97 for dog muscles compared to 2.17-2.84 for cat muscles. Thus the two- to threefold higher Q at VO2max for dog muscles compared to cat muscles is not due to a greater number of capillaries.

Animals↗

Physiological characteristics of elite male runners in and off-season.

The seasonal variation in physiological characteristics of elite male runners was studied. Five middle distance (mean age 21 yrs) and 5 long distance runners (23 yrs), all members of the Swedish national track and field team, participated in treadmill tests on 4 occasions over a period of one year: in January, in May, during the highly competitive summer period and the following January. The maximal oxygen uptake (VO2 max, ml X kg-1 X min-1) increased successively during the season and was significantly (p less than 0.01) higher during the summer than in the winter (74.2 to 77.4 ml X kg-1 X min-1). From the competitive summer period to the second winter the VO2 max (ml X kg-1 X min-1) showed a significant decrease. The absolute value of VO2 max (1/min) was not significantly changed during this one-year period, however. Running economy was evaluated from oxygen uptake determinations at 15 km/h (VO2 15) and 20 km/h (VO2 20). Slightly lower values of VO2 15 and VO2 20 were noted during the season, and after one year VO2 20 was significantly decreased. Such an improvement in running economy with time was also found in a larger group of elite runners (n = 16) when determined from an average of 7 treadmill tests. The running velocity corresponding to a blood lactate concentration of 4 mmol/l increased from January to the summer season. The blood lactate concentration after exhaustion (VO2 max test) increased significantly from January to May.

Adolescent↗

[Environmental physiological characteristics of some mosses in Shanghai: a preliminary study].

The preliminary study on the environmental physiological characteristics of bryophytes collected from Shanghai area, including their responses to drought, temperature, humidity, light and growth substrate, as well as their tissue culture technology showed that different species of bryophytes under same conditions and the same species under different conditions had different drought resistance. Adding organic matter to sand soil and short-illumination benefited the growth of bryophytes. Treating with proper growth hormones could accelerate the reproduction and growth of bryophyte. Hogland medium was suitable for the tissue culture of bryophytes.

Bryophyta↗

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

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.

Analysis of Variance↗

Physiological characteristics of identified motor units in the mouse extensor digitorum longus muscle: an in vitro approach.

Physiological, histochemical, and morphometric properties of fast-twitch single motor units were studied in mouse extensor digitorum longus muscles in an in vitro ventral root-nerve-muscle preparation. Single motor units were functionally isolated by microdissection of the ventral root, and the glycogen depletion technique was used to demonstrate the component muscle fibers. Monoclonal antibodies were used to identify their myosin heavy chain composition. The technique allows one to correlate physiological characteristics of single motor units with fiber type but is less useful for morphological assessment of motor unit size as a result of failure to deplete glycogen from all fibers of motor units containing fibers with high oxidative capacity.

Animals↗