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1.
Nutrient Cycling in Agroecosystems - The nitrogen (N) fertilizer application rate (kg ha?1 year?1) in pastoral dairy systems affects the flow of N through the soil,...  相似文献   
2.
Milk proteins including casein are sources of peptides with bioactivity. One of these peptides is beta-casomorphin (BCM) which belongs to a group of opioid peptides formed from β-casein variants. Beta-casomorphin 7 (BCM7) has been demonstrated to be enzymatically released from the A1 or B β-casein variant. Epidemiological evidence suggests the peptide BCM 7 is a risk factor for development of human diseases, including increased risk of type 1 diabetes and cardiovascular diseases but this has not been thoroughly substantiated by research studies. High performance liquid chromatography coupled to UV-Vis and mass spectrometry detection as well as enzyme–linked immunosorbent assay (ELISA) has been used to analyze BCMs in dairy products. BCMs have been detected in raw cow's milk and human milk and a variety of commercial cheeses, but their presence has yet to be confirmed in commercial yoghurts. The finding that BCMs are present in cheese suggests they could also form in yoghurt, but be degraded during yoghurt processing. Whether BCMs do form in yoghurt and the amount of BCM forming or degrading at different processing steps needs further investigation and possibly will depend on the heat treatment and fermentation process used, but it remains an intriguing unknown.  相似文献   
3.
A process has been developed for the synthesis of a new photochromic alkylene sulfide derivative. The process involves the synthesis of an alkylene sulfide with terminal free amino groups and a novel unsymmetrical photochromic diarylperfluorocyclopentene containing an aldehyde group, which coupled together to produce the corresponding Schiff base. The structures of the products were confirmed by a range of spectroscopic techniques.  相似文献   
4.
Lifetime home standards (LTHS) are a set of standards aimed at making homes more accessible. Previous research, however, indicates that LTHS do not adequately meet the needs of those with sensory impairments. Now, with visual impairment set to increase globally and acknowledging the recognised link between quality of dwelling and wellbeing, this article aims to examine the experiences of visually impaired people living in lifetime homes. The objectives are to investigate existing lifetime homes and to identify whether LTHS meet occupants’ needs. Qualitative semi-structured interviews were carried out with six visually impaired people living in homes designed to LTHS in Northern Ireland. Collected data was analysed using interpretative phenomenological analysis identifying three super-ordinate themes: (1) living with visual impairment; (2) design considerations and (3) coping strategies. A core theme of balance between psychological and physical needs emerged through interconnection of super-ordinate themes. Although there are benefits to living in lifetime homes, negative aspects are also apparent with occupants employing several coping strategies to overcome difficulties. Whilst residents experience negative emotions following visual impairment diagnoses, results suggest that occupants still regard their homes as key places of security and comfort in addition to then highlighting the need for greater consideration of specific individual needs within general guidelines.  相似文献   
5.
Metallurgical and Materials Transactions A - The misorientation of 515 grain boundaries has been determined using electron backscatter diffraction data from an 18 μm thick copper foil with...  相似文献   
6.
The National Institute for Occupational Safety and Health has carried out a field study to determine the vibration and impact levels that self-contained breathing apparatus are subjected to in simulated fire fighting use. Also, the forces that facemask retaining straps experience in simulated fire fighting use were measured. Notes: Dr. Crouch is on the staff of the National Institute for Occupational Safety and Health. Shamsul Abedin is with the Engineering and Test Division of Dayton T. Brown, Inc. Mention of company names or products does not constitute endorsement by the National Institute for Occupational Safety and Health.  相似文献   
7.
Within the housing segregation literature major disagreements have developed over two fundamental issues: (1) the role that whites' aversion to racially mixed neighbourhoods plays in causing modern segregation in the US; and (2) the factors that underlie this aversion, including the effects of inter‐racial contact on whites' neighbourhood racial preferences and whether these preferences reflect neighbourhood stereotyping as opposed to pure racial prejudice. Extant evidence on these issues is either old or indirect. This paper provides direct evidence on these issues using new data from the Multi‐City Study of Urban Inequality. The results suggest that (1) whites' neighbourhood racial preferences play an important role in explaining the racial composition of their neighbourhoods; (2) inter‐racial contact in neighbourhoods and workplaces leads to a greater willingness among whites to live with blacks; and (3) although younger and more educated whites express a stronger taste for integration than other whites, the magnitude of these differences leads to only a small increase in the black percentage of the neighbourhood. In addition, the results provide no evidence in support of the hypothesis that whites stereotype black neighbourhoods rather than blacks per se.  相似文献   
8.
In order to evaluate the efficacy of constructed wetlands for treatment of domestic wastewater for small communities located in rural areas, small-scale wetland mesocosms (400 L each) containing two treatment designs (a mixture of Typha, Scirpus, and Juncus species; control without vegetation) were planted into two depths (45 or 60 cm) with pea gravel. Each mesocosm received 19 L/day of primary-treated domestic sewage. Mesocosms were monitored (inflow and outflow samples) on a monthly basis over a 2-year period for pH, total suspended solids (TSS), 5-day biochemical oxygen demand (BOD(5)), total Kjeldahl nitrogen (TKN), dissolved oxygen (DO), and conductivity. Microbiological analyses included enumeration of fecal coliforms, enterococci, Salmonella, Shigella, Yersinia, and coliphage. Significant differences between influent and effluent water quality for the vegetated wetlands (p<0.05) were observed in TSS, BOD(5), and TKN. Increased DO and reduction in fecal coliform, enterococcus, Salmonella, Shigella, Yersinia, and coliphage populations also were observed in vegetated wetlands. Greatest microbial reductions were observed in the planted mesocosms compared to those lacking vegetation. Despite marked reduction of several contaminants, wetland-treated effluents did not consistently meet final discharge limits for receiving bodies of water. Removal efficiencies for bacteria and several chemical parameters were more apparent during the initial year compared to the second year of operation, suggesting concern for long-term efficiency and stability of such wetlands.  相似文献   
9.
The contribution of atmospheric deposition to emissions of trace metals in stormwater runoff was investigated by quantifying wet and dry deposition fluxes and stormwater discharges within a small, highly impervious urban catchment in Los Angeles. At the beginning of the dry season in spring 2003, dry deposition measurements of chromium, copper, lead, nickel, and zinc were made monthly for 1 year. Stormwater runoff and wet deposition samples also were collected, and loading estimates of total annual deposition (wet+dry) were compared with annual stormwater loads. Wet deposition contributed 1-10% of the total deposition inside the catchment, indicating the dominance of dry deposition in semi-arid regions such as Los Angeles. Based on the ratio of total deposition to stormwater, atmospheric deposition potentially accounted for as much as 57-100% of the total trace metal loads in stormwater within the study area. Despite potential bias attributable to processes that were not quantified in this study (e.g., resuspension out of the catchment or sequestration within the catchment), these results demonstrate atmospheric deposition represents an important source of trace metals in stormwater to waterbodies near urban centers.  相似文献   
10.
Observation of collapsed coiled (steel) furniture springs has been utilized for several decades or more by arson investigators as an indicator of whether an accelerant or smoldering source (such as a cigarette) caused a fire. This paper cites the contradictory literature, synopsizes metallurgical phenomena operative when coiled steel springs are subjected to fires, and presents empirical data from U.S. Federal Bureau of Investigation (FBI) Laboratory testing. It is concluded that observation of the collapsed state of coiled furniture/bedding springs is not a reliable indicator of whether a fire was initiated by a smoldering cigarette or accelerated by the presence of a hydrocarbon.  相似文献   
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