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11.
The land application of aged chortetracycle (CTC) and tylosin-containing swine manure was investigated to determine associated impacts to soil microbial respiration, nutrient (phosphorus, ammonium, nitrate) cycling, and soil microbial community structure under laboratory conditions. Two silty clay loam soils common to southeastern South Dakota were used. Aerobic soil respiration results using batch reactors containing a soil-manure mixture showed that interactions between soil, native soil microbial populations, and antimicrobials influenced CO(2) generation. The aged tylosin treatment resulted in the greatest degree of CO(2) inhibition, while the aged CTC treatment was similar to the no-antimicrobial treatment. For soil columns in which manure was applied at a one-time agronomic loading rate, there was no significant difference in soil-P behavior between either aged CTC or tylosin and the no-antimicrobial treatment. For soil-nitrogen (ammonium and nitrate), the aged CTC treatment resulted in rapid ammonium accumulation at the deeper 40cm soil column depth, while nitrate production was minimal. The aged CTC treatment microbial community structure was different than the no-antimicrobial treatment, where amines/amide and carbohydrate chemical guilds utilization profile were low. The aged tylosin treatment also resulted in ammonium accumulation at 40 cm column depth, however nitrate accumulation also occurred concurrently at 10 cm. The microbial community structure for the aged tylosin was also significantly different than the no-antimicrobial treatment, with a higher degree of amines/amides and carbohydrate chemical guild utilization compared to the no-antimicrobial treatment. Study results suggest that land application of CTC and tylosin-containing manure appears to fundamentally change microbial-mediated nitrogen behavior within soil A horizons.  相似文献   
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Campylobacter jejuni is an important human food-borne pathogen that can contaminate meat and poultry during processing. Consequently, strategies are sought to reduce the carriage of C. jejuni in food animals before they arrive at the abattoir. Thymol is a natural product that reduces survivability of Campylobacter in vitro, but its rapid absorption from the proximal alimentary tract limits its bactericidal efficacy in vivo. Thymol-β-d-glucopyranoside is more resistant to absorption than free thymol, but its administration to chickens has not been reported. In the present studies, 1 mM thymol-β-d-glucopyranoside was shown to exhibit near equal anti-Campylobacter activity as 1 mM thymol when incubated anaerobically in avian crop or cecal contents in vitro, resulting in reductions of 1.10–2.32 log10 colony forming units mL?1 in C. jejuni concentrations after 24 h incubation. In a follow-up live animal study, oral administration of thymol-β-d-glucopyranoside, but not free thymol, significantly lowered (>10-fold) recovery of Campylobacter from the crop of market-aged broilers when compared to placebo-treated controls (n = 6 broilers/treatment). Neither thymol-β-d-glucopyranoside nor thymol affected recovery of Campylobacter from cecal contents of the treated broilers. These results indicate that rapid absorption or passage of free thymol from the crop precluded its anti-Campylobacter activity at this site and throughout the entire gastrointestinal tract. Conversely, lower recovery of Campylobacter from the crop of birds treated with thymol-β-d-glucopyranoside indicates this conjugate was retained and able to be hydrolyzed to biologically active free thymol at this site as intended, yet was not sufficiently protected to allow passage of efficacious amounts of the intact glycoside to the lower gut. Nevertheless, these results warrant further research to see if higher doses or encapsulation of thymol-β-d-glucopyranoside or similar glycosides may yield an efficacious additive to reduce carriage of Campylobacter as well as other pathogens throughout the avian gut.  相似文献   
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Since the beginning of the 1990s, local authorities in Israel have been engaged in promoting advanced Wastewater Treatment Plant (WWTP) projects throughout the country, resulting in the "wastewater treatment revolution" of the 1990s. These achievements are extremely important in the water-scarce country, as untreated or partially treated wastewater has become a major source of pollution of Israel's fresh-water resources, and reuse of high-quality effluents can expand the national water potential. Many of these projects are regional schemes based on a central WWTP, serving a few neighboring municipalities. This paper presents two case studies of such regional cooperation: the "Karmiel Region Union of Towns for Sewage Treatment" and the "Treatment and Reuse of Wastewater in the area of the Hadera Stream, Ltd." corporation. The findings suggest that regional cooperation can be an efficient tool in promoting advanced wastewater treatment, and has several advantages: an efficient use of limited resources (financial and land); balancing disparities between municipalities (size, socio-economic features, consciousness and ability of local leaders); and reducing spillover effects. However, some problems were reported in both cases and should be addressed.  相似文献   
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This longitudinal study examined relations among interpersonal demands of jobs and the psychological health, job and work involvements, and job satisfaction of workers. Two samples of archival data were collected between the 1940s and 1971. Workers of both sexes who were psychologically healthier in adolescence and earlier adulthood manifested greater involvement and (for men only) satisfaction later in adulthood. People in interpersonally demanding jobs showed greater involvement and satisfaction; men were more involved, but not more satisfied, than women. Older cohort members who were more psychologically healthy were more likely to enter, and remain in, interpersonally demanding jobs. However, this relationship was moderated by both chronological age and historical period, which are cohort variables that are often ignored in the occupational literature. The common practice of presuming generalizability across these dimensions may not be warranted.  相似文献   
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Innovations in water chain are discussed based on experiences in the Netherlands. The available and new technological options, as well as their dissemination in the Netherlands, are presented for the prevailing system with add-on technologies (elongation), and for the emerging separation system with technologies at the source. Numerous new options are available for both systems but these options are rarely used. The low use is explained using economic theories and with practical examples from the Netherlands. In order to foster innovations, the mainstream, evolutionary, and behavioral theories pinpoint respectively the pricing of common goods, broad support of concerted action, and support for innovators’ entry. These actions may all be needed. Experiences with a stakeholder cluster in water management suggest that markets for high value water use invoke innovations and low-cost technology adaptations. The systematic development of services that foster high value water-based activities is recommended.  相似文献   
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Rates and direction of movement in the sand dollar Peronella lesueuri were measured in summer and winter in Cockburn Sound, a large coastal embayment in south-western Australia. P. lesueuri was found to have a diurnal activity pattern throughout the year and had a greater movement rate in the summer (mean of 5.3 cm h?1, day; 3.9 cm h?1, night) than in the winter (mean of 2.7 cm h?1, day; 2.0 cm h?1, night). Seasonal change in temperature and physiological requirements by the sand dollar are the most likely reason for the seasonal differences. Reasons for diurnal variation were not clear. Direction of movement was found to be random at both times of the year. Based on these movement rates, one sand dollar can bioturbate an approximate area of 0.1 m2 day?1 and 36.4 m2 year?1. At a conservative density estimate of 0.5 sand dollars per m2 it takes approximately 20 days for the sand dollars to rework the entire area of the sediments in the habitats they occupy.  相似文献   
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