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981.
Easy-care or natural lambing pertainsto those sheep able to successfully lamb andrear at least one lamb without human assistancein a difficult environment. Such sheep may havea higher survival rate, lower lamb mortality,and require less shepherding at lambing thanother sheep breeds or strains. The farmer orshepherd account of easy-care lambing revealsseveral themes. Firstly, stock were bred tosurvive or suit local environments orconditions, particularly steep hill country inNew Zealand. This involved extensive culling ofundesirable dams, regardless of how well theymight perform in traits other than the abilityto survive and to produce live lambs atweaning. Sheep that did have problems wereoften assisted, recorded or marked and thenculled at an appropriate time; thus bothartificial (culling) and natural selection wereused. Secondly, natural selection enabled theimportant traits to be identified and they weresubsequently incorporated into artificialselection programs. Thirdly, the practice wasnecessitated by the impracticality ofsupervising lambing in difficult terrain andthe cost of skilled farm labor. Finally, it wasacknowledged that disturbance at lambingcreated problems and most importantly, theeasy-care approach reduced some of the problemstraditionally associated with lambing.Easy-care lambing systems thus aim to minimizesome of the detrimental effects associated withcarefully supervised lambing in someenvironments, by selecting sheep to suit boththat environment and modern farm management.They overcame pervasive influences our culturallegacy was exerting on the way we interact withanimals, and may have produced a system more inkeeping with the biology of the animal in anextensive environment.  相似文献   
982.
983.
984.
Continuous Improvement can be applied to every business function, including environmental auditing. The benefits of customer focus and performance measurement are realized in a more efficient business system and a higher level of environmental compliance. Lockheed has successfully used Continuous Improvement principles in the development and implementation of its environmental auditing program, which are described in this article.  相似文献   
985.
This research investigated the effects of extending the holding time of samples for microbial analysis beyond the standard of 24 hours for purposes such as watershed characterization. Experiments were conducted with both sanitary wastewater and stormwater samples. The refrigerated samples (4 degrees C) were held for up to 9 days before being analyzed for two pathogens (Pseudomonas aeruginosa and Staphylococcus aureus) and five indicator organisms (total coliform, fecal coliform, fecal streptococcus, enterococcus, and Escherichia coli) by membrane filtration. The concentrations (as colony-forming units per 100 mL) were normalized by log10(transformation and used in subsequent statistical analysis testing for significant differences. The results suggested that the concentrations of microorganisms in water samples analyzed on days 1 and 2 did not vary significantly in 8 of 13 analyses. The results of a field study concluded that the concentration of fecal coliform did not change significantly between 7 hours holding time and greater than 24 hours holding time for fecal coliform.  相似文献   
986.
We report a case of a female fetus born to an unrelated couple with a complex fetal phenotype of a pleural effusion, a cardiac malformation, and syndactyly of the toes. Prenatal exome sequencing identified a variant of uncertain significance in the PORCN gene that was upgraded to likely pathogenic following postnatal clinical examination. The phenotype described in cases with variants in the PORCN gene is often associated with findings that cannot be prospectively diagnosed by ultrasonography. This is the first report of a prenatal phenotype involving a fetal effusion associated with variants in the PORCN gene, with skeletal findings identified later in gestation on ultrasonography. The diagnosis was confirmed on neonatal examination.  相似文献   
987.
This work describes the development, optimisation and validation of an analytical method for the rapid determination of 17 priority pharmaceutical compounds and endocrine disrupting chemicals (EDCs). Rather than studying compounds from the same therapeutic class, the analyses aimed to determine target compounds with the highest risk potential (with particular regard to Scotland), providing a tool for further monitoring in different water matrices. Prioritisation was based on a systematic environmental risk assessment approach, using consumption data; wastewater treatment removal efficiency; environmental occurrence; toxicological effects; and pre-existing regulatory indicators. This process highlighted 17 compounds across various therapeutic classes, which were then quantified, at environmentally relevant concentrations, by a single analytical methodology. Analytical determination was achieved using a single-step solid phase extraction (SPE) procedure followed by high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). The fully optimised method performed well for the majority of target compounds, with recoveries >71% for 15 of 17 analytes. The limits of quantification for most target analytes (14 of 17) ranged from 0.07 ng/L to 1.88 ng/L in river waters. The utility of this method was then demonstrated using real water samples associated with a rural hospital/setting. Eight compounds were targeted and detected, with the highest levels found for the analgesic, paracetamol (at up to 105,910 ng/L in the hospital discharge). This method offers a robust tool to monitor high priority pharmaceutical and EDC levels in various aqueous sample matrices.  相似文献   
988.
In 2007, a 1.5‐year field‐scale study was initiated by the U.S. Geological Survey to evaluate the dissipation of contaminants of emerging concern (CECs) following a first agronomic biosolids application to nonirrigated farmland. CECs with the greatest decrease in concentration in the surface biosolids at 180 days post‐application included indole, d‐limonene, p‐cresol, phenol, and skatol. CECs that were present in the largest concentration in 180‐day‐weathered biosolids included stanols, nonylphenols, bisphenol A, bis(2‐ethylhexyl) phthalate, hexahydrohexamethyl cyclopenta‐benzopyran (HHCB), and triclosan. CECs that were detected in pre‐application soil were 3‐beta coprostanol, skatol, acetophenone, beta‐sitosterol, beta‐stigmastanol, cholesterol, indole, p‐cresol, and phenol, most of which are biogenic sterols or fragrances that have natural plant sources in addition to anthropogenic sources, yet their concentrations increased (in some cases, substantially) following biosolids application. Preliminary data indicate the nonylphenols (including NPEO1, NPEO2), OPEO1, benzo[a]pyrene, diethyl phthalate, d‐limonene, HHCB, triclosan, and possibly 3‐beta coprostanol, skatol, beta‐sitosterol, cholesterol, indole, and p‐cresol, migrated downward through the soil by 468 days post‐application, but indicated little uptake by mature wheat plants. This study indicates that some CECs are sufficiently persistent and mobile to be vertically transported into the soil column following biosolids applications to the land surface, even in semiarid regions.  相似文献   
989.
In designing cities, the label of the green movement these days is being applied to almost everything—starting from works of environmental non-governmental organizations and international as well as local conservation organizations to grass-roots resistance activism including radical environmentalism. This paper seeks to understand the motivation—the paradigm—behind the green movement initiatives and how the paradigm appears to shift from the ground reality. Conclusions suggest that, on one hand, environmental problems are far from being a matter of common sense and, on the other, the matter of intellectual and technological developments—the outcomes of rigorous academic research reflected in endless literature predominantly comprising the fields of environmental sociology, environmental anthropology, and conservation psychology—are in reality often found to be dealt with by shallow planning and policy practices without even realizing the big-picture that the paradigm is merely being used as an advertizing tool for making business profit. It is expected that, unless a shift from such negative practices towards a conscious and genuine commitment to proactive environmental stewardship is made, the situation will continue to be exacerbated.  相似文献   
990.
Because of continued habitat destruction and species extirpations, the need to use captive breeding for conservation purposes has been increasing steadily. However, the long-term demographic and genetic effects associated with releasing captive-born individuals with varied life histories into the wild remain largely unknown. To address this question, we developed forward-time, agent-based models for 4 species with long-running captive-breeding and release programs: coho salmon (Oncorhynchus kisutch), golden lion tamarin (Leontopithecus rosalia), western toad (Anaxyrus boreas), and Whooping Crane (Grus americana). We measured the effects of supplementation by comparing population size and neutral genetic diversity in supplemented populations to the same characteristics in unaltered populations 100 years after supplementation ended. Releasing even slightly less fit captive-born individuals to supplement wild populations typically resulted in reductions in population sizes and genetic diversity over the long term when the fitness reductions were heritable (i.e., due to genetic adaptation to captivity) and populations continued to be regulated by density-dependent mechanisms over time. Negative effects for species with longer life spans and lower rates of population replacement were smaller than for species with shorter life spans and higher rates of population replacement. Programs that released captive-born individuals over fewer years or that avoided breeding individuals with captive ancestry had smaller reductions in population size and genetic diversity over the long term. Relying on selection in the wild to remove individuals with reduced fitness mitigated some negative demographic effects, but at a substantial cost to neutral genetic diversity. Our results suggest that conservation-focused captive-breeding programs should take measures to prevent even small amounts of genetic adaptation to captivity, quantitatively determine the minimum number of captive-born individuals to release each year, and fully account for the interactions among genetic adaptation to captivity, population regulation, and life-history variation.  相似文献   
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