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141.
Human noroviral infections are generally more common during winters in temperate regions. This study used a murine norovirus (MNV) as a human norovirus surrogate to test the effect of water temperature (4 and 25°C) on virus survival and its susceptibility to the levels of monochloramine (~1.89 ppm) to terminally disinfect municipally treated potable waters. The titre of MNV remained essentially unchanged for at least 24 h in raw river water at both temperatures. The virus became undetectable in <2 h in monochloramine-containing samples held at 25°C, but its titre remained virtually unaltered at 4°C (P < 0.05) under the same conditions. These findings strongly suggest that water temperature can influence the norovirucidal activity of monochloramine and its possible impact on the seasonality of outbreaks of noroviral infections.  相似文献   
142.
Climate change is one of the main challenges faced by mankind in this century. Although developing countries have little historical responsibility for climate change, they are likely to be most affected by it since they lack resources to cope with or to adapt to its effects. Studies show that the semi-arid northeast region of Brazil – where the country's poorest populations are concentrated – is one of the most vulnerable to climate change and thus likely to suffer its impacts more severely. The present paper addresses these problems by presenting a concrete initiative for strengthening adaptive capacity in the rural community of Pintadas as a first step in the development of a comprehensive methodology to help smallholder farmers in the region adapt to climate change. Based on the project results this paper highlights the integration of development, adaptive capacity and adaptation strategies. Furthermore, the necessity of vulnerability studies and concrete local experiences is highlighted in order to develop adaptation strategies that can alleviate poverty and minimize climate change impacts for the poor.  相似文献   
143.
Subterranean mammals rely to a great extent on audition for communication and to be alerted to danger. The only hitherto published report on burrow acoustics revealed that in tunnels of blind mole-rats (Spalax ehrenbergi), airborne sounds of 440 Hz propagated best whereas lower and higher frequencies were effectively attenuated. Morpho-functional analyses classify the ear of subterranean mammals as a low-sensitivity and low-frequency device. Concordantly, hearing is characterized by low sensitivity and a restricted frequency range tuned to low frequencies (0.5–4 kHz). Some authors considered the restricted hearing in subterranean mammals vestigial and degenerate due to under-stimulation. In contrast to this view stand a rich (mostly low-frequency) vocal repertoire and progressive structural specializations of the middle and inner ear. Thus, other authors considered these hearing characteristics adaptive. To test the hypothesis that acoustical environment in burrows of different species of subterranean mammals is similar, we measured sound attenuation in burrows of Fukomys mole-rats (formerly known as Cryptomys, cf. Kock et al. 2006) of two differently sized species at different locations in Zambia. We show that in these burrows, low-frequency sounds (200–800 Hz) are not only least attenuated but also their amplitude may be amplified like in a stethoscope (up to two times over 1 m). We suggest that hearing sensitivity has decreased during evolution of subterranean mammals to avoid over-stimulation of the ear in their natural environment. We dedicate this work to Mathias Kawalika, who died in March 2006.  相似文献   
144.
Biochar addition to agricultural soil has been suggested to mitigate climate change through increased biogenic carbon storage and reduction of greenhouse gas emissions. We measured the fluxes of N2O, CO2, and CH4 after adding 9 t ha?1 biochar on an agricultural soil in Southern Finland in May 2009. We conducted these measurements twice a week for 1.5 months, between sowing and canopy closure, to capture the period of highest N2O emissions, where the potential for mitigation would also be highest. Biochar addition increased CH4 uptake (96% increase in the average cumulative CH4 uptake), but no statistically significant differences were observed in the CO2 and N2O emissions between the biochar amended and control plots. Added biochar increased soil water holding capacity by 11%. Further studies are needed to clarify whether this may help balance fluctuations in water availability to plants in the future climate with more frequent drought periods.  相似文献   
145.
Many environmental chemicals and pesticides have been found to alter neuroendocrine communication in exposed biological objects. The environmental loads have primary and secondary effects that can alter the homeostatic regulation potential. Since it is difficult to avoid human exposition, a potentially important area of research to develop in vivo and in vitro experimental models. In this context, the primary aim of this study was to demonstrate the effects of chlorobenzenes on adrenocorticotrophic hormone (ACTH) release. In our experimental study, male Wistar rats were exposed to 0.1, 1.0 and 10 μg/b.w. (body weight) kg of 1,2,4- trichlorobenzene and hexachlorobenzene (ClB) mix via gastric tube for 30, 60 or 90 days. At the endpoints of the experiment blood samples were taken and animals were decapitated. Primary, monolayer adenohypophysis cell cultures were prepared by enzymatic and mechanical digestion. The ACTH hormone content in serum and supernatant media was measured by immuno-chemiluminescence assay. The Mg2 +-dependent ATPase activity was determined by modified method of Martin and Dotty. Significant differences were detected in the hormone release between the control and treated groups. The hormone release was enhanced characteristically in exposed groups depending upon the dose and duration of exposure. The Mg2 +-ATPase activity enhanced after chronic and subtoxic ClB exposition. Light microscopy revealed that the adenohypophysis seemed to be more abundant. Results indicate that Wistar rats exposed to subtoxic ClB have direct and indirect effects on hypothalamus–hypophysis–adrenal axis.  相似文献   
146.
Journal of Material Cycles and Waste Management - Wood biomass fly ash can contribute to a more sustainable urban infrastructure, but requires efficient recycling strategies. This paper...  相似文献   
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