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351.
This article presents a history of curriculum revision. Internal and external factors prompting the initial curriculum review included the Pew Report, a vision in the college for reform, and faculty retreats focusing on curriculum. The reformed curriculum was designed around a "core plus elective" strategy and was implemented following development by faculty representatives and approval by college and university levels of review. The curriculum was reviewed after being revised and after new courses were first offered, with further review of a few courses with specific challenges. Outcomes assessment was performed and curricular adjustments made. Challenges that arose during the process included organizing and documenting content as well as communicating the content and philosophy of the new curriculum to the various affected constituencies. A summary of factors considered essential to the successful design, implementation, and review of the new curriculum is presented; the majority of these factors would be applicable to reforms at other institutions.  相似文献   
352.
Suburban habitats in naturally forested areas present a conundrum in the urban–rural habitat network. Typically, these habitats contain less than half of the native woodland bird species that would exist at these sites if they were not developed. They also contain more total bird species than if these sites were left in a natural state. This apparent contradiction raises the question of “How do suburban habitats function in the urban–rural habitat network?” In this study, we analyze bird distributions on three rural-to-urban gradients in different ecoregions of the United States: Oxford, Ohio; Saint Paul, Minnesota; and Palo Alto, California. All three gradients exhibit similar patterns of extinction of native species followed by invasion of common species and subsequent biotic homogenization with urbanization. This patterning suggests that suburban land uses, those represented by the intermediate levels of development on the gradients, are a point of extirpation for woodland birds as well as an entry point for invasive species into urban systems. Furthermore, there are consistent patterns in the functional characteristics of the bird communities that also shift with intensifying urbanization, providing insight on the possible mechanisms of homogenization and community structure in urban ecosystems including an increase in the number of broods per year, a shift in nesting strategies, a decrease in insectivorous individuals, an increase in granivorous individuals, and a decrease in territoriality. Consequently, it appears that there are specific traits that drive the shift in community composition in response to urban and suburban land use. These results have significant implications for improving understanding of the mechanisms of suburban community ecology and conserving birds in urban habitat networks.  相似文献   
353.
1. In each of four experiments 140 or 160 1‐d‐old broiler chicks were fed for 14 d on diets based on crystalline amino acids and other purified ingredients. The basal diet was a purified diet found suitable for 7‐d‐old chicks.

2. Growth was poorer with the basal diet than with a practical diet and it was not improved by an increase in the concentration of vitamins or supplementation with isolated soy protein, water or liver.

3. An increase in the amount of mineral mixture or of magnesium alone gave a significant improvement in growth, so that it approximated that obtained with the practical diet. Food conversion efficiency was significantly better with the mineral‐supplemented than with the practical diet.

4. The basal purified diet supplemented with magnesium to provide 684 mg Mg per kilogram was satisfactory for the early growth; chicks fed on this diet did not respond to sources of “unidentified factors” such as fresh or freeze‐dried liver and soy‐protein.  相似文献   

354.
A 12-month-old Thoroughbred colt was presented for chronic recurrent respiratory disease characterised by persistent nasal discharge, intermittent pyrexia and coughing of several months' duration. These episodes were responsive to empirical antimicrobial therapy but returned once therapy was discontinued. History, physical examination and initial diagnostics were suggestive of bacterial pneumonia and possible underlying immunodeficiency. Serum immunoglobulin analysis and peripheral blood lymphocyte phenotyping revealed low serum IgG and IgM concentrations. In this 12-month-old colt, low serum IgG concentration was the most diagnostic parameter and supported a presumptive diagnosis of transient hypogammaglobulinaemia of the young. The colt responded favourably to repeated treatment with antimicrobials for bacterial pneumonia, and serial immunologic testing over the following months showed gradual increase in serum IgG and IgM concentrations, supporting the diagnosis of delayed development of humoral immunity in this patient.  相似文献   
355.
356.
Sperm DNA fragmentation is one of the major causes of infertility; the sperm chromatin dispersion test (SCDt) evaluates this parameter and offers the advantage of species‐specific validated protocol and ease of use under field conditions. The main purpose of this study was to evaluate sperm DNA fragmentation dynamics in both fresh and post‐thaw bottlenose dolphin sperm using the SCDt following different cryopreservation protocols to gain new information about the post‐thaw differential sperm DNA longevity in this species. Fresh and cryopreserved semen samples from five bottlenose dolphins were examined for sperm DNA fragmentation dynamics using the SCDt (Halomax®). Sperm DNA fragmentation was assessed immediately at collection and following cryopreservation (T0) and then after 0.5, 1, 4, 8, 24, 48 and 72 h incubation at 37°C. Serially collected ejaculates from four dolphins were frozen using different cryopreservation protocols in a TES‐TRIS‐fructose buffer (TTF), an egg‐yolk‐free vegetable lipid LP1 buffer (LP1) and human sperm preservation medium (HSPM). Fresh ejaculated spermatozoa initially showed low levels of DNA fragmentation for up to 48 h. Lower Sperm DNA fragmentation (SDF) was found in the second fresh ejaculate compared to the first when more than one sample was collected on the same day (p < 0.05); this difference was not apparent in any other seminal characteristic. While there was no difference observed in SDF between fresh and frozen–thawed sperm using the different cryopreservation protocols immediately after thawing (T0), frozen–thawed spermatozoa incubated at 37°C showed an increase in the rate of SDF after 24 h. Sperm frozen in the LP1? buffer had higher levels (p < 0.05) of DNA fragmentation after 24‐ and 48‐h incubation than those frozen in TTF or HSPM. No correlation was found between any seminal characteristic and DNA fragmentation in either fresh and/or frozen–thawed samples.  相似文献   
357.
358.
Soybean accounts for over a quarter of the world's oilseed consumption and over 70% of the world's protein meal consumption. The separate development of high oleic, low linolenic acid (HOLL) soybean and high-protein (HP) soybean means that no soybean cultivar on the market has an optimal fatty acid profile and increased protein. The objective of this study was to develop and evaluate high protein, high oleic acid, and low linolenic acid (HP-HOLL) soybean. A five-gene stack was created using a two-phase forward breeding scheme and marker-assisted selection method. Forty-six HP-HOLL lines from three genetic backgrounds were grown in six environments in the Southeast United States. Although genotype-by-environment interaction was significant for seed composition traits, lines met the >75% and <3% cutoffs for oleic acid and linolenic acid, respectively, and met or exceeded the protein concentration of the HP parent. No negative interaction could be detected between the HP and HOLL traits. Additionally, yield testing in four environments indicated yield parity for some lines, suggesting HP and HOLL soybean cultivars with high yield could be selected.  相似文献   
359.
The western corn rootworm (WCR), Diabrotica virgifera virgifera, is the most important pest of corn in the US Corn Belt. Economic estimates indicate that costs of control and yield loss associated with WCR damage exceed $US 1 billion annually. Historically, corn rootworm management has been extremely difficult because of its ability to evolve resistance to both chemical insecticides and cultural control practices. Since 2003, the only novel commercialized developments in rootworm management have been transgenic plants expressing Bt insecticidal proteins. Four transgenic insecticidal proteins are currently registered for rootworm management, and field resistance to proteins from the Cry3 family highlights the importance of developing traits with new modes of action. One of the newest approaches for controlling rootworm pests involves RNA interference (RNAi). This review describes the current understanding of the RNAi mechanisms in WCR and the use of this technology for WCR management. Further, the review addresses ecological risk assessment of RNAi and insect resistance management of RNAi for corn rootworm. © 2016 Society of Chemical Industry  相似文献   
360.
Systematic seasonal variations in the stable carbon isotopic signature of methane gas occur in the anoxic sediments of Cape Lookout Bight, a lagoonal basin on North Carolina's Outer Banks. Values for the carbon isotope ratio (delta 13C) of methane range from -57.3 per mil during summer to -68.5 per mil during winter in gas bubbles with an average methane content of 95%. The variations are hypothesized to result from changes in the pathways of microbial methane production and cycling of key substrates including acetate and hydrogen. The use of stable isotopic signatures to investigate the global methane cycle through mass balance calculations, involving various sediment and soil biogenic sources, appears to require seasonally averaged data from individual sites.  相似文献   
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