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41.
Toby J. Hibbitts Martin J. Whiting Devi M. Stuart-Fox 《Behavioral ecology and sociobiology》2007,61(8):1169-1176
Many species possess multiple sexually dimorphic traits, which incorporate different sensory modalities (e.g., acoustic, olfactory
and visual), although their relative roles in sexual selection and in determining reproductive success are still poorly understood
for most taxa. We assessed the role of multiple male traits, including one acoustic (dominant call frequency) and one visual
(yellow throat patch) trait, in residency advertisement, contest behavior, and breeding success in barking geckos (Ptenopus garrulus garrulus). We show that male barking geckos maintain largely exclusive home ranges, with a trend for larger males to maintain larger
home ranges. We also show that larger males have a lower dominant calling frequency. When aggressive behavior was elicited
in the field using a recorded call of average frequency, resident males with low frequency calls were more likely to respond
aggressively and charge the speaker compared to males with high frequency calls. However, body size and small relative throat
patch size, rather than call frequency, were the best predictors of overall aggressiveness. Body size was also the best predictor
of whether males bred. We suggest that call frequency in this crepuscular species constitutes an effective long-range signal
of body size, used by males for remote rival assessment and to advertise home range boundaries in low-light environments. 相似文献
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43.
Suren N. Kulshreshtha Devi D. Tewari 《Journal of the American Water Resources Association》1991,27(2):227-236
ABSTRACT: Water abundance has led most North American societies to use water freely without priorizing its use. As water scarcity becomes reality in the southern part of Saskatchewan, planners and managers of water require information about the value of water in irrigation, as well as in alternative uses. In this study, the value of water to the producer in irrigation is developed both for the short and long run. The basis of this imputation is a derived demand function for water using linear programming. Water demand was bound to be inelastic at lower prices, and highly elastic at higher prices. The short-run value of water varied between $0.44 and $127.82 (1986 dollars) per acre-foot for different levels of product prices. However, the long-run value was estimated between zero and $1.59 per acre-foot of water. 相似文献
44.
Recreation and Radial Growth of Pine Forests of the Natural Monument “Lake Turgoyak”, Southern Urals
Kukarskih V. V. Devi N. M. Bubnov M. O. Agafonov L. I. 《Russian Journal of Ecology》2022,53(3):169-180
Russian Journal of Ecology - The study presents results of the influence of recreational impact on the radial growth of Scots pine (Pinus sylvestris L.) in old-growth stands at the sites with the V... 相似文献
45.
Ningombam Linthoingambi Devi Shihua Qi Paromita Chakraborty Gan Zhang Ishwar Chandra Yadav 《环境科学学报(英文版)》2011,23(5):808-815
Thirty-six polyurethane foam disk passive air samplers (PUF-PAS) were deployed over a year during January to December, 2009
at three locations, i.e., Imphal (urban site), Thoubal (rural site) and Waithou (alpine site) of Manipur, to assess the seasonal local
atmospheric emission of selected organochlorine pesticides (OCPs). The average concentration of HCHs monitored at mountain site
during hot season (Mar, Apr, and May) and rainy seasons (Jun, Jul, Aug, and Sep) were 403 and 349 pg/m3, respectively. DDTs had a
high concentration with 384 pg/m3 at rural site and 379 pg/m3 at urban site during hot seasons. Endosulfans and chlordane were found
high in concentration during hot seasons (260 pg/m3) and low during retreating monsoon seasons (44 pg/m3) at rural site. Most of the
OCPs concentrations were high during cultivation period. The OCP concentrations of rainy season were highly correlated (p < 0.01)
with OCPs of hot seasons. Further, positive correlation (p < 0.05) was also obtained between cold seasons and retreating monsoon.
Principal component analysis showed a significant correlation among the four seasons and distribution pattern of OCPs in air. Back
trajectory analysis by using HYPSLIT model showed a long range air transport of OCPs to the present study area. Present OCP levels
at Manipur is an outcome of both local emission and also movement of air mass by long range atmospheric transport. 相似文献
46.
The aim of this study was to examine effects of lead (Pb)-based paints on malondialdehyde (MDA) levels as an indicator for lipid peroxidation; and on activities of serum antioxidant enzymes activities such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) in industrial painters. A total of 67 male painters and 50 age-matched and gender-matched controls were included in this cross-sectional study. There were 19 smokers and 48 non-smokers in the paint-exposed group and 20 smokers and 30 non-smokers in the control group. Hemoglobin concentrations were lower in painters’ blood compared to controls. The blood Pb concentrations were higher in painters compared to controls. SOD and GPx activities were significantly lower in painters compared to controls. MDA concentration was found to be significantly elevated. Smoking was found to be a major confounder. Data suggest that Pb-based paints affect oxidant parameters in occupationally exposed workers. 相似文献
47.
S. Palani S. Raja R. Praveen Kumar K. Sakthivel K. Devi B. Senthil Kumar 《毒物与环境化学》2013,95(6):1199-1211
Hyperlipidemia is an associated complication of diabetes mellitus. Many spices and herbs are known to be hypoglycemic. Mahonia leschenaultia Takeda (Berberidaceae) (MLT) is a traditional medicinal plant that is commonly used against diseases in India and other Asian countries. The aim of this study is to identify the phytoconstituents by gas chromatography–mass spectrography (GC–MS) and evaluate the antihyperglycemic and antihyperlipidemic effects of the ethanol extract of MLT on streptozotocin (STZ)-induced diabetic rats. Phytoconstituents like oleicacid, 9,12-octadecadienoic acid (Z, Z)-n-hexadecanoic acid were identified as high % peak when compared with other compounds by GC–MS. STZ-induced diabetic animals were fed with plant extracts at different doses (250 or 500 mg kg?1 body wt) of ethanol extract of MLT. The results of the study revealed a significant increase in total hemoglobin and glycosylated hemoglobin along with the reduction in hyperglycemia and hyperlipidemia effects in MLT-treated STZ-induced diabetic rats compared to diabetic only rats. Further, ethanol extracts of MLT-treated animals at 500 mg kg?1 showed that shrinkage of β cells of islets of Langerhans was restored as evidenced by histological studies of pancreas of diabetic animals. Thus the ethanol extract of MLT might serve as a reliable adjuvant for antihyperglycemic and antihyperlipidemic effects of STZ, and may be promising for development of phytomedicines for diabetes mellitus. 相似文献
48.
Grigor’ev A. A. Devi N. M. Kukarskikh V. V. V’yukhin S. O. Galimova A. A. Moiseev P. A. Fomin V. V. 《Russian Journal of Ecology》2019,50(4):311-322
Russian Journal of Ecology - Analysis of the age structure of Dahurian larch (Larix gmelinii Rupr.) forests in the western part of the Putorana Plateau (Sukhie Gory Range) and comparison of... 相似文献
49.
Roshan Appa V. A. Mhaisalkar Amit Bafana S. Saravana Devi Kannan Krishnamurthi Tapan Chakrabarti Pravin K. Naoghare 《Environmental monitoring and assessment》2018,190(8):489
Environmental occurrence of CECs poses a great threat to both aquatic life and human health. The aim of this study was to optimize and validate SPE/LC-(ESI)MS-MS method for simultaneous quantitative monitoring of two sub-classes of CECs (pharmaceuticals and hormones) and to estimate the concentrations of select CECs in environmental water samples. For all the tested analytes, recoveries in laboratory reagent water were greater than 81%. Average percent (relative standard deviation) RSD of the analytes in recovery, repeatability, and reproducibility experiments were ≤?10%. Determination coefficients (r2) of primidone, diclofenac, testosterone, and progesterone were estimated to be 0.9979, 0.9972, 0.9968, and 0.9962, respectively. Limits of detection (LOD) for primidone, diclofenac, testosterone, and progesterone were 4.63 ng/L, 5.36 ng/L, 0.55 ng/L, and 0.88 ng/L, respectively. Limits of quantification (LOQ) for primidone, diclofenac, testosterone, and progesterone were 14.72 ng/L, 17.06 ng/L, 1.766 ng/L, and 2.813 ng/L, respectively. Average recoveries in environmental water and wastewater samples were greater than 74% and RSD were ≤?7%. Trace levels (68.33–125.70 ng/L) of primidone were detected in four environmental water samples, whereas diclofenac was not detected in any of the tested sample. Trace levels of progesterone were observed in two environmental samples (16.64 –203.73 ng/L), whereas testosterone was detected in STP inlet sample (178.16 ng/L). 相似文献
50.
Naser A. Anjum Pallavi Sharma Sarvajeet S. Gill Mirza Hasanuzzaman Ekhlaque A. Khan Kiran Kachhap Amal A. Mohamed Palaniswamy Thangavel Gurumayum Devmanjuri Devi Palanisamy Vasudhevan Adriano Sofo Nafees A. Khan Amarendra Narayan Misra Alexander S. Lukatkin Harminder Pal Singh Eduarda Pereira Narendra Tuteja 《Environmental science and pollution research international》2016,23(19):19002-19029
Plants have to counteract unavoidable stress-caused anomalies such as oxidative stress to sustain their lives and serve heterotrophic organisms including humans. Among major enzymatic antioxidants, catalase (CAT; EC 1.11.1.6) and ascorbate peroxidase (APX; EC 1.11.1.11) are representative heme enzymes meant for metabolizing stress-provoked reactive oxygen species (ROS; such as H2O2) and controlling their potential impacts on cellular metabolism and functions. CAT mainly occurs in peroxisomes and catalyzes the dismutation reaction without requiring any reductant; whereas, APX has a higher affinity for H2O2 and utilizes ascorbate (AsA) as specific electron donor for the reduction of H2O2 into H2O in organelles including chloroplasts, cytosol, mitochondria, and peroxisomes. Literature is extensive on the glutathione-associated H2O2-metabolizing systems in plants. However, discussion is meager or scattered in the literature available on the biochemical and genomic characterization as well as techniques for the assays of CAT and APX and their modulation in plants under abiotic stresses. This paper aims (a) to introduce oxidative stress-causative factors and highlights their relationship with abiotic stresses in plants; (b) to overview structure, occurrence, and significance of CAT and APX in plants; (c) to summarize the principles of current technologies used to assay CAT and APX in plants; (d) to appraise available literature on the modulation of CAT and APX in plants under major abiotic stresses; and finally, (e) to consider a brief cross-talk on the CAT and APX, and this also highlights the aspects unexplored so far. 相似文献