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Arunachalam Thangakumar Khader Syed Zameer Ahmed Syed Zameer Ahmed Sidhra Vetrivel Manimaran Syed Ameen Syed Tajudeen Ameer Khadharu Ibrahim Sheriff Prabhu Puniethaa Jayachandran Philp Robinson M. Sabu Dastageer 《Environmental science and pollution research international》2020,27(9):9058-9058
Environmental Science and Pollution Research - The correct presentation of the Author names are shown in this paper. 相似文献
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Chadwick D. Rittenhouse Joshua J. Millspaugh Andrew B. Cooper Michael W. Hubbard Steven L. Sheriff Robert A. Gitzen 《Environmental and Ecological Statistics》2008,15(1):39-47
Wildlife resource selection studies typically compare used to available resources; selection or avoidance occurs when use
is disproportionately greater or less than availability. Comparing used to available resources is problematic because results
are often greatly influenced by what is considered available to the animal. Moreover, placing relocation points within resource
units is often difficult due to radiotelemetry and mapping errors. Given these problems, we suggest that an animal’s resource
use be summarized at the scale of the home range (i.e., the spatial distribution of all point locations of an animal) rather
than by individual points that are considered used or available. To account for differences in use-intensity throughout an
animal’s home range, we model resource selection using kernel density estimates and polytomous logistic regression. We present
a case study of elk (Cervus elaphus) resource selection in South Dakota to illustrate the procedure. There are several advantages of our proposed approach. First,
resource availability goes undefined by the investigator, which is a difficult and often arbitrary decision. Instead, the
technique compares the intensity of animal use throughout the home range. This technique also avoids problems with classifying
locations rigidly as used or unused. Second, location coordinates do not need to be placed within mapped resource units, which
is problematic given mapping and telemetry error. Finally, resource use is considered at an appropriate scale for management
because most wildlife resource decisions are made at the level of the patch. Despite the advantages of this use-intensity
procedure, future research should address spatial autocorrelation and develop spatial models for ordered categorical variables. 相似文献
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Michael Ackah Alfred Kwablah Anim Eva Tabuaa Gyamfi Nafisatu Zakaria John Hanson Delali Tulasi Sheriff Enti-Brown Esther Saah-Nyarko Nash Owusu Bentil Juliet Osei 《Environmental monitoring and assessment》2014,186(1):621-634
The heavy metals (Fe, Zn, Pb, Ni, Cr, Co, and Cd) burden in wastewater, soil, and vegetable samples from a wastewater irrigated farm located at KorleBu, Accra has been investigated. Flame atomic absorption spectrometry after microwave digestion using a combination of HNO3, HCl, and H2O2 (for water), and HNO3 and HCl (for soil and vegetables). The mean concentrations (in milligrams per kilogram) of heavy metals in the soil samples were in the order of Fe (171?±?5.22)?>?Zn (36.06?±?4.54)?>?Pb (33.35?±?35.62)?>?Ni (6.31?±?8.15)?>?Cr (3.40?±?3.63)?>?Co (1.36?±?0.31)?>?Cd (0.43?±?0.24), while the vegetables were in the order of Fe (183.11?±?161.2)?>?Zn (5.38?±?3.50)?>?Ni (3.52?±?1.27)?>?Pb (2.49?±?1.81)?>?Cr (1.46?±?0.51)?>?Co (0.66?±?0.25)?>?Cd (0.36?±?0.15). The bioconcentration factors suggest environmental monitoring for the heavy metals as follows: Cd (0.828), Cr (0.431), Ni (0.558), Co (0.485), and Fe (1.067). Estimated daily intakes were very low for both children and adults except Fe (0.767 mg/kg/day) in children. The population that consume vegetables from the study area were, however, estimated to be safe based on the results obtained from the health risk index, which were all?<?<1. The sodium absorption ratio according to FAO (1985) classifications indicate that the wastewater in the study area is unsuitable for irrigation purposes. 相似文献
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Sheriff Adewuyi Nurudeen O. Sanyaolu Saliu A. Amolegbe Abdulahi O. Sobol Olujinmi M. Folarin 《环境科学学报(英文版)》2012,24(9):1702-1708
Chemical reduction of nitrate using metal nanoparticles has received increasing interest due to over-dependence on groundwater and consequence health hazard of the nitrate ion. One major drawback of this technique is the agglomeration of nanoparticles leading to the formation of large flocs. A low cost biopolymeric material, poly [β-(1 → 4)-2-amino-2-deoxy-D-glucopyranose] (β-PADG) obtained from deacetylated chitin was used as stabilizer to synthesize zero valent nickel (ZVNi) nanoparticles. The β-PADG-ZVNi nanocomposite was characterized using infra red (IR), UV-Vis spectrophotometric techniques and Scanning Electron Microscope (SEM). The morphology of the composite showed that β-PADG stabilized-ZVNi nanoparticles were present as discrete particles. The mean particle size was estimated to be (7.76 ± 2.98) nm and surface area of 87.10 m2/g. The stabilized-ZVNi nanoparticles exhibited markedly greater reactivity for reduction of nitrate in water with 100% conversion within 2 hr contact owing to less agglomeration. Varying the β-PADG-to-ZVNi ratio and the ZVNi-to-nitrate molar ratio generally led to a faster nitrate reduction. About 3.4-fold difference in the specific reaction rate constant suggests that the application of the β-PADG-stabilizer not only increased the specific surface area of the resultant nanoparticles, but also greatly enhanced the surface reactivity of the nanoparticles per unit area. 相似文献
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Maternal effects may be a major factor influencing the demography of populations. In mammals, the transmission of stress hormones between mother and offspring may play an important role in these effects. Laboratory studies have shown that stressors during pregnancy and lactation result in lifelong programming of the offspring phenotype. However, the relevance of these studies to free-living mammals is unclear. The 10-year snowshoe hare (Lepus americanus) cycle is intimately linked to fluctuating predation pressure and predation risk. The enigma of these cycles is the lack of population growth following the decline phase, when the predators have virtually all disappeared and the food supply is ample. We have shown that a predator-induced increase in maternal stress hormone levels resulted in a decline in reproduction. Here we examine population and hormone changes over a four-year period from the increase (2005) to the decline (2008). We report (1) that an index of maternal stress (fecal corticosteroid metabolite [FCM] concentrations) fluctuates in synchrony with predator density during the breeding season; (2) that maternal FCM levels are echoed in their offspring, and this occurs at a population-wide level; and (3) that higher maternal FCM levels at birth are correlated with an increased responsiveness of the hypothalamic-pituitary-adrenal (HPA) axis in their progeny. Our results show an intergenerational inheritance of stress hormones in a free-ranging population of mammals. We propose that the lack of recovery of reproductive rates during the early low phase of the hare cycle may be the result of the impacts of intergenerational, maternally inherited stress hormones caused by high predation risk during the decline phase. 相似文献
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Michael Ackah Alfred Kwablah Anim Nafisatu Zakaria Juliet Osei Esther Saah-Nyarko Eva Tabuaa Gyamfi Delali Tulasi Sheriff Enti-Brown John Hanson Nash Owusu Bentil 《Environmental monitoring and assessment》2014,186(12):8499-8507
Twenty-three soft drink samples (i.e., four pineapple-based fruit drinks, eight citrus-based fruit juices, one soya-based drink, three cola carbonated drinks, one apple-based fruit drink, and six cocktail fruit drinks) were randomly purchased from retail outlets in an urban market in Accra and analyzed for the concentrations of iron, cobalt, cadmium, zinc, lead, and copper using flame atomic absorption spectrometry. The mean concentration of iron and cadmium were 0.723?±?0.448 mg/L and 0.032?±?0.012 mg/L, respectively. The mean cobalt concentration was 0.071?±?0.049 mg/L, while the mean Zn concentration in the samples was 0.060?±?0.097 mg/L. The mean concentrations of Pb and Cu in the fruit juice samples were 0.178?±?0.091 mg/L and 0.053?±?0.063 mg/L respectively. About 78 % of the samples exceeded the United States Environmental Protection Agency (USEPA) maximum contaminant level of 0.3 mg/L prescribed for iron, whereas all the samples exceeded the USEPA maximum contaminant level of 0.005 mg/L prescribed for cadmium. About 91 % of the samples exceeded the EU maximum contaminant level prescribed for lead insoft drinks. 相似文献
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Arunachalam Thangakumar Khader Syed Zameer Ahmed Syed Zameer Ahmed Sidhra Vetrivel Manimaran Syed Ameen Syed Tajudeen Ameer Khadharu Ibrahim Sheriff Prabhu Puniethaa Jayachandran Philp Robinson Sabu Dastageer M. 《Environmental science and pollution research international》2020,27(9):9038-9057
Environmental Science and Pollution Research - Multiple drug resistance and increased side effects due to allopathic drugs has warned scientific community with a global alarm to identify molecules... 相似文献
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A key obstacle to practical application of mechanism design theory to regulation is the difficulty of obtaining consistent beliefs regarding information that theoretical models assume to be commonly held. This article presents a solution to this problem by developing an easily implemented empirical methodology with which the government can use available data to develop beliefs regarding the technology and distribution of types in a regulated sector characterized by hidden information. Results are used to calibrate a second-best land conservation mechanism and evaluate its cost relative to simpler alternatives. 相似文献
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