Developing as a College Science Teacher: Using Identity to Examine Transformation

Guided by identity theory, this study investigated how a college biology professor’s early career experiences contributed to the transformation of his identity as a college science teacher. This study showcases the four components of identity as described by Gee as a lens and it specifically focuses on the emergent role of institutional identity and its associated conflicts with incompatible belief systems. This qualitative study illustrated the utility of Gee’s theory to study how various components of identity can be useful to examine the transformation of a college faculty member. The participant’s position as a non-tenured faculty member created dissonance between his developing beliefs concerning quality science instruction and those imposed on him by his departmen

Farm Service Agency Direct Farm Loan Program Effectiveness Study

The three primary objectives of the Effectiveness Study are to: (1) identify groups being served by FSA direct farm loan programs, (2) examine the length of time borrowers remain in the programs and the proportion of borrowers who exit or 'graduate' from the programs, and (3) measure and identify ways of reducing loan subsidy rates. The study found that direct Farm Loan Programs (FLPs) appear to be serving their intended clientele. Recent FLP borrowers are more financially stressed than non-borrowers and would be generally considered as family farms. About 78 to 92 percent would qualify as small family farms using USDA's Small Farms Commission definition. FLP credit market penetration is relatively high among farms likely to be eligible for these credit programs, despite the fact that these programs represent a relatively small proportion of total outstanding agricultural debt. Increasing market penetration or the share of farms served by the program would require greater obligation funding and hence greater budgetary costs. Conversely, implementing more rigorous loan eligibility criteria would likely lower the number of operators receiving loans and hence loan loss occurrences and subsidy rates would likely fall. The majority of FSA Direct borrowers from FY 1994-1996 used FLPs as a transitional tool. At time of origination, FSA Direct borrowers had fewer years of farming experience than the farming population at large. More than half of these borrowers no longer had active FLP loans by the end of November 2004. So for the majority of borrowers, FLPs are not a lifetime credit source. FLPs are helping farmers move to commercial credit or aiding farmers who subsequently leave farming completely, as is common among U.S. farmers. Not surprisingly, farmers in stronger financial condition originating FSA Direct loans are more likely to exit and have fewer outstanding loans with FSA. FSA experiences higher loan loss rates than conventional agricultural lenders. This is to be expected because commercial lenders can be more selective in choosing borrowers and price loans to match risk profiles which FSA does not do. In essence, FSA's mission is to provide credit to riskier 'creditworthy' borrowers. The agency is accomplishing this goal. The natural consequence is that FSA loan loss rates are higher than for conventional lenders. Whether the current borrowers are too risky or should even riskier borrowers be included are policy questions. The analysis indicates that attempts to cut losses systematically would imply denying credit to some current borrowers.Agricultural Finance,

Farm Service Agency Direct Farm Loan Program Effectiveness Study

This final report presents the results of an independent, performance-focused review of the effectiveness of Farm Service Agency (FSA) Direct Farm Loan Programs (FLPs) as requested by the Office of Management and Budget (OMB) in the 2005 Passback for FSA. The study focuses on FSA’s direct Farm Ownership (FO), Farm Operating (OL), and Emergency (EM) loan programs

Molt-dependent transcriptomic analysis of cement proteins in the barnacle Amphibalanus amphitrite

Abstract Background A complete understanding of barnacle adhesion remains elusive as the process occurs within and beneath the confines of a rigid calcified shell. Barnacle cement is mainly proteinaceous and several individual proteins have been identified in the hardened cement at the barnacle-substrate interface. Little is known about the molt- and tissue-specific expression of cement protein genes but could offer valuable insight into the complex multi-step processes of barnacle growth and adhesion. Methods The main body and sub-mantle tissue of the barnacle Amphibalanus amphitrite (basionym Balanus amphitrite) were collected in pre- and post-molt stages. RNA-seq technology was used to analyze the transcriptome for differential gene expression at these two stages and liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) was used to analyze the protein content of barnacle secretions. Results We report on the transcriptomic analysis of barnacle cement gland tissue in pre- and post-molt growth stages and proteomic investigation of barnacle secretions. While no significant difference was found in the expression of cement proteins genes at pre- and post-molting stages, expression levels were highly elevated in the sub-mantle tissue (where the cement glands are located) compared to the main barnacle body. We report the discovery of a novel 114kD cement protein, which is identified in material secreted onto various surfaces by adult barnacles and with the encoding gene highly expressed in the sub-mantle tissue. Further differential gene expression analysis of the sub-mantle tissue samples reveals a limited number of genes highly expressed in pre-molt samples with a range of functions including cuticular development, biominerialization, and proteolytic activity. Conclusions The expression of cement protein genes appears to remain constant through the molt cycle and is largely confined to the sub-mantle tissue. Our results reveal a novel and potentially prominent protein to the mix of cement-related components in A. amphitrite. Despite the lack of a complete genome, sample collection allowed for extended transcriptomic analysis of pre- and post-molt barnacle samples and identified a number of highly-expressed genes. Our results highlight the complexities of this sessile marine organism as it grows via molt cycles and increases the area over which it exhibits robust adhesion to its substrate.http://deepblue.lib.umich.edu/bitstream/2027.42/115487/1/12864_2015_Article_2076.pd

Deficiency in the endocytic adaptor proteins PHETA1/2 impairs renal and craniofacial development

A critical barrier in the treatment of endosomal and lysosomal diseases is the lack of understanding of the in vivo functions of the putative causative genes. We addressed this by investigating a key pair of endocytic adaptor proteins, PH domain-containing endocytic trafficking adaptor 1 and 2 (PHETA1/2; also known as FAM109A/B, Ses1/2, IPIP27A/B), which interact with the protein product of OCRL, the causative gene for Lowe syndrome. Here, we conducted the first study of PHETA1/2 in vivo, utilizing the zebrafish system. We found that impairment of both zebrafish orthologs, pheta1 and pheta2, disrupted endocytosis and ciliogenesis in renal tissues. In addition, pheta1/2 mutant animals exhibited reduced jaw size and delayed chondrocyte differentiation, indicating a role in craniofacial development. Deficiency of pheta1/2 resulted in dysregulation of cathepsin K, which led to an increased abundance of type II collagen in craniofacial cartilages, a marker of immature cartilage extracellular matrix. Cathepsin K inhibition rescued the craniofacial phenotypes in the pheta1/2 double mutants. The abnormal renal and craniofacial phenotypes in the pheta1/2 mutant animals were consistent with the clinical presentation of a patient with a de novo arginine (R) to cysteine (C) variant (R6C) of PHETA1. Expressing the patient-specific variant in zebrafish exacerbated craniofacial deficits, suggesting that the R6C allele acts in a dominant-negative manner. Together, these results provide insights into the in vivo roles of PHETA1/2 and suggest that the R6C variant is contributory to the pathogenesis of disease in the patient

Do Students See the “Selection” in Organic Evolution? A Critical Review of the Causal Structure of Student Explanations

This paper critically reviews and characterizes the student's causal-explanatory understanding; this is done as a step toward explicating the problematic of evolution education as it concerns the cognitive difficulties in understanding Darwin's theory of natural selection. The review concludes that the student's understanding is fundamentally different from Darwin's, for the student understands evolutionary change as necessary individual transformation caused by the transformative action of various physical and behavioral factors. This is in complete contrast to Darwin's (and even the Darwinian's, for that matter) understanding of evolutionary change as a change caused by accumulative selection. Hence, to understand natural selection, the student has to learn to “see” how the accumulative selection causes evolutionary change

Evolutionary view of acyl-CoA diacylglycerol acyltransferase (DGAT), a key enzyme in neutral lipid biosynthesis

<p>Abstract</p> <p>Background</p> <p>Triacylglycerides (TAGs) are a class of neutral lipids that represent the most important storage form of energy for eukaryotic cells. DGAT (acyl-CoA: diacylglycerol acyltransferase; EC 2.3.1.20) is a transmembrane enzyme that acts in the final and committed step of TAG synthesis, and it has been proposed to be the rate-limiting enzyme in plant storage lipid accumulation. In fact, two different enzymes identified in several eukaryotic species, DGAT1 and DGAT2, are the main enzymes responsible for TAG synthesis. These enzymes do not share high DNA or protein sequence similarities, and it has been suggested that they play non-redundant roles in different tissues and in some species in TAG synthesis. Despite a number of previous studies on the DGAT1 and DGAT2 genes, which have emphasized their importance as potential obesity treatment targets to increase triacylglycerol accumulation, little is known about their evolutionary timeline in eukaryotes. The goal of this study was to examine the evolutionary relationship of the DGAT1 and DGAT2 genes across eukaryotic organisms in order to infer their origin.</p> <p>Results</p> <p>We have conducted a broad survey of fully sequenced genomes, including representatives of Amoebozoa, yeasts, fungi, algae, musses, plants, vertebrate and invertebrate species, for the presence of DGAT1 and DGAT2 gene homologs. We found that the DGAT1 and DGAT2 genes are nearly ubiquitous in eukaryotes and are readily identifiable in all the major eukaryotic groups and genomes examined. Phylogenetic analyses of the DGAT1 and DGAT2 amino acid sequences revealed evolutionary partitioning of the DGAT protein family into two major DGAT1 and DGAT2 clades. Protein secondary structure and hydrophobic-transmembrane analysis also showed differences between these enzymes. The analysis also revealed that the MGAT2 and AWAT genes may have arisen from DGAT2 duplication events.</p> <p>Conclusions</p> <p>In this study, we identified several DGAT1 and DGAT2 homologs in eukaryote taxa. Overall, the data show that DGAT1 and DGAT2 are present in most eukaryotic organisms and belong to two different gene families. The phylogenetic and evolutionary analyses revealed that DGAT1 and DGAT2 evolved separately, with functional convergence, despite their wide molecular and structural divergence.</p