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Abstract Background The eastern oyster, Crassostrea virginica (Gmelin 1791), is an economically important species cultured in many areas in North America. It is also ecologically important because of the impact of its filter feeding behaviour on water quality. Populations of C. virginica have been threatened by overfishing, habitat degradation, and diseases. Through genome research, strategies are being developed to reverse its population decline. However, large-scale expressed sequence tag (EST) resources have been lacking for this species. Efficient generation of EST resources from this species has been hindered by a high redundancy of transcripts. The objectives of this study were to construct a normalized cDNA library for efficient EST analysis, to generate thousands of ESTs, and to analyze the ESTs for microsatellites and potential single nucleotide polymorphisms (SNPs). Results A normalized and subtracted C. virginica cDNA library was constructed from pooled RNA isolated from hemocytes, mantle, gill, gonad and digestive tract, muscle, and a whole juvenile oyster. A total of 6,528 clones were sequenced from this library generating 5,542 high-quality EST sequences. Cluster analysis indicated the presence of 635 contigs and 4,053 singletons, generating a total of 4,688 unique sequences. About 46% (2,174) of the unique ESTs had significant hits (E-value ≤ 1e-05) to the non-redundant protein database; 1,104 of which were annotated using Gene Ontology (GO) terms. A total of 35 microsatellites were identified from the ESTs, with 18 having sufficient flanking sequences for primer design. A total of 6,533 putative SNPs were also identified using all existing and the newly generated EST resources of the eastern oysters. Conclusion A high quality normalized cDNA library was constructed. A total of 5,542 ESTs were generated representing 4,688 unique sequences. Putative microsatellite and SNP markers were identified. These genome resources provide the material basis for future microarray development, marker validation, and genetic linkage and QTL analysis.

Multiple barriers in the structure and function of American higher education conspire to impede the success of interdisciplinary programs in environmental studies. We present an amalgamated narrative case study to illustrate how barriers operate both independently and in concert to undermine individual and programmatic goals, innovation, and operations, resulting in lost opportunities for faculty, students, and curricula, and other program elements. Barriers are illustrated stemming from a variety of sources, including academic organizational culture, structure, and leadership. An analysis of three main barriers and strategies to address them led us to produce recommendations that foster new patterns of faculty interaction and leadership. These recommendations are based on a foundation of human dignity, shared respect, and common values. In turn, they require a clear conception of interdisciplinarity and integration, and practical means to achieve them in diverse contexts.

A major unresolved issue in the cloning of mammals by somatic cell nuclear transfer (SCNT) is the mechanism by which the process fails after embryos are transferred to the uterus of recipients before or during the implantation window. We investigated this problem by using RNA sequencing (RNA-seq) to compare the transcriptomes in cattle conceptuses produced by SCNT and artificial insemination (AI) at day (d) 18 (preimplantation) and d 34 (postimplantation) of gestation. In addition, endometrium was profiled to identify the communication pathways that might be affected by the presence of a cloned conceptus, ultimately leading to mortality before or during the implantation window. At d 18, the effects on the transcriptome associated with SCNT were massive, involving more than 5,000 differentially expressed genes (DEGs). Among them are 121 genes that have embryonic lethal phenotypes in mice, cause defects in trophoblast and placental development, and/or affect conceptus survival in mice. In endometria at d 18,

The contemporary fields of interdisciplinary studies and the policy sciences have evolved over similar intellectual paths and timelines, beginning in the early 20th century. Both have their roots in professional efforts--within and outside the academy--to address numerous, growing, and complex problems that face humanity. The policy sciences' approach to integration via interdisciplinarity serves the civic and public processes of community and decision making that address these problems, while at the same time respecting the individual human being. This goal explicitly seeks dignity for all individuals in healthy environments. The policy sciences offer a framework and an intellectual toolbox with a fundamental set of operations to achieve integration via interdisciplinarity in the interests of problem solving. This framework guides interdisciplinarity in practical, teachable, and learnable terms, the history of which mirrors the evolution of interdisciplinary studies. A review of the policy sciences in the context of interdisciplinary studies emphasizes their shared heritage and raises important questions about how isolated communities of scholars and practitioners with a convergent evolution might collaborate to promote greater achievement of their common goals.

Nontuberculous mycobacteria (NTM) are opportunistic human pathogens. Several species of NTM, including members of the Mycobacterium avium complex (MAC), can cause potentially life-threatening pulmonary infections that are difficult to treat [...]

This work compares object replacement and object presentation as causes of avoidance (new object reaction or neophobia). The movements of wild black rats, Rattus rattus, living in an automated plus maze were recorded (1) after replacing a familiar object (in a familiar place) with a series of novel objects, (2) after presenting a novel object in a familiar place where there had been no object. Replacing one object by another did not delay entry to the maze arm containing it. In contrast, the presence of a new object in a previously empty arm did increase the latency of the first approach (new object reaction), although after the first entry, the rate of visiting the arms and the time spent in them, which are measures of subsequent approach, were unaffected. Hence, this form of neophobic behavior was evoked only by the presence of a new object where none had been before. Differences with earlier reports can be resolved in most cases when attention is paid to the difference between presentation and replacement.