908 research outputs found
A Qualitative and Quantitative Study of Behavioral Characteristics and Instructional Patterns of Selected Elementary Music Teachers.
The purpose of this study was to identify what good elementary music teachers do by: (a) identifying primary factors that contribute to effective music teaching as defined by exemplary behaviors of recognized music specialists; (b) examining the relationship of teacher-defined instructional values, which emerge through qualitative study to operationally defined characteristics of effective music instruction resulting from quantitative research; and (c) exploring the possibility that qualitative and quantitative methods of research might be complementary. Nine experienced, elementary music specialists from three regions of the country were observed, audio- and videotaped, and interviewed. Interviews with selected students and instructional documents supplemented the data. Both qualitative evaluation and quantitative measurement were used to analyze the data. While modifications of operational definitions for elementary level were required, results showed that the teachers\u27 instructional patterns consistently supported previous research in the areas of teacher magnitude (Yarbrough, 1975) and sequential patterns of instruction (Yarbrough & Price, 1989). Analysis of sequential patterns enabled categorical expansion of complete/incomplete patterns. Qualitative evaluation revealed high intensity behaviors (Madsen & Geringer, 1989), personal values relative to effective teaching (Porter & Brophy, 1988), and increased the potential for accurate interpretation. Specific instructional patterns and behavioral characteristics may be useful for training prospective music teachers and promoting formative evaluation among experienced specialists. Generalizations, however, should be made with caution until this collaborative form of research is developed further and the number of participants expanded
The cell line A-to-I RNA editing catalogue
Adenosine-to-inosine (A-to-I) RNA editing is a common post transcriptional modification. It has a critical role in protecting against false activation of innate immunity by endogenous double stranded RNAs and has been associated with various regulatory processes and diseases such as autoimmune and cardiovascular diseases as well as cancer. In addition, the endogenous A-to-I editing machinery has been recently harnessed for RNA engineering. The study of RNA editing in humans relies heavily on the usage of cell lines as an important and commonly-used research tool. In particular, manipulations of the editing enzymes and their targets are often developed using cell line platforms. However, RNA editing in cell lines behaves very differently than in normal and diseased tissues, and most cell lines exhibit low editing levels, requiring over-expression of the enzymes. Here, we explore the A-to-I RNA editing landscape across over 1000 human cell lines types and show that for almost every editing target of interest a suitable cell line that mimics normal tissue condition may be found. We provide CLAIRE, a searchable catalogue of RNA editing levels across cell lines available at http://srv00.recas.ba.infn.it/atlas/claire.html, to facilitate rational choice of appropriate cell lines for future work on A-to-I RNA editing
Natural feed additives as alternative to in-feed medication
The use of antibiotics in livestock production is very common and widespread. The reason for their use can be very diverse. Examples are the treatment of clinically sick animals, the improvement of growth performance, as well as the prevention of common bacterial infections. However, the extensive use of such antimicrobials raised concerns of increasing the incidence of resistant pathogenic bacteria, which has a negative impact not only on livestock production, but also on human health. In the last years, many different substances have been investigated as suitable alternatives to the use of antibiotics as growth promoting agents and as prophylactic substances
PCNA Ubiquitination Is Important, But Not Essential for Translesion DNA Synthesis in Mammalian Cells
Translesion DNA synthesis (TLS) is a DNA damage tolerance mechanism in which specialized low-fidelity DNA polymerases bypass replication-blocking lesions, and it is usually associated with mutagenesis. In Saccharomyces cerevisiae a key event in TLS is the monoubiquitination of PCNA, which enables recruitment of the specialized polymerases to the damaged site through their ubiquitin-binding domain. In mammals, however, there is a debate on the requirement for ubiquitinated PCNA (PCNA-Ub) in TLS. We show that UV-induced Rpa foci, indicative of single-stranded DNA (ssDNA) regions caused by UV, accumulate faster and disappear more slowly in Pcna(K164R/K164R) cells, which are resistant to PCNA ubiquitination, compared to Pcna(+/+) cells, consistent with a TLS defect. Direct analysis of TLS in these cells, using gapped plasmids with site-specific lesions, showed that TLS is strongly reduced across UV lesions and the cisplatin-induced intrastrand GG crosslink. A similar effect was obtained in cells lacking Rad18, the E3 ubiquitin ligase which monoubiquitinates PCNA. Consistently, cells lacking Usp1, the enzyme that de-ubiquitinates PCNA exhibited increased TLS across a UV lesion and the cisplatin adduct. In contrast, cells lacking the Rad5-homologs Shprh and Hltf, which polyubiquitinate PCNA, exhibited normal TLS. Knocking down the expression of the TLS genes Rev3L, PolH, or Rev1 in Pcna(K164R/K164R) mouse embryo fibroblasts caused each an increased sensitivity to UV radiation, indicating the existence of TLS pathways that are independent of PCNA-Ub. Taken together these results indicate that PCNA-Ub is required for maximal TLS. However, TLS polymerases can be recruited to damaged DNA also in the absence of PCNA-Ub, and perform TLS, albeit at a significantly lower efficiency and altered mutagenic specificity
The Origin of Faint Tidal Features Around Galaxies in the RESOLVE Survey
We study tidal features (TFs) around galaxies in the REsolved Spectroscopy of a Local VolumE (RESOLVE) survey. Our sample consists of 1048 RESOLVE galaxies that overlap with the DECam Legacy Survey, which reaches an r-band 3σ depth of ∼27.9 mag arcsec−2 for a 100 arcsec2 feature. Images were masked, smoothed, and inspected for TFs like streams, shells, or tails/arms. We find TFs in 17±2% of our galaxies, setting a lower limit on the true frequency. The frequency of TFs in the gas-poor (gas-to-stellar mass ratio < 0.1) subsample is lower than in the gas-rich subsample (13±3% vs. 19±2%). Within the gas-poor subsample, galaxies with TFs have higher stellar and halo masses, ∼3× closer distances to nearest neighbors (in the same group), and possibly fewer group members at fixed halo mass than galaxies without TFs, but similar specific star formation rates. These results suggest TFs in gas-poor galaxies are typically streams/shells from dry mergers or satellite disruption. In contrast, the presence of TFs around gas-rich galaxies does not correlate with stellar or halo mass, suggesting these TFs are often tails/arms from resonant interactions. Similar to TFs in gas-poor galaxies, TFs in gas-rich galaxies imply 1.7x closer nearest neighbors in the same group; however, TFs in gas-rich galaxies are associated with diskier morphologies, higher star formation rates, and higher gas content. In addition to interactions with known neighbors, we suggest that TFs in gas-rich galaxies may arise from accretion of cosmic gas and/or gas-rich satellites below the survey limit
Gal-On v. Attorney General (Summary)
By a majority of six justices out of a panel of eleven, the High Court of Justice rejected petitions challenging the constitutionality of the Citizenship and Entry to Israel Act. The majority justices acknowledged there was a constitutional right for family life, which derives from the right to human dignity, but held that the scope of the right does not extend to realizing the right specifically in Israel. It was also held that to the extent that constitutional rights have been violated, including the right to equality, it is a violation that passes muster under the test of the Limitations Clause. They believe that the potential risk of terrorist activity posed by the foreign partners and the public interest in safety and security - which they find to be a worthy purpose - outweigh the infringement on the constitutional right, and is thus proportional. The minority justices believe that because the statue effects primarily Arab Israelis it violates the right to equality, in addition to the right to family life, which is rendered meaningless without the ability to exercise it in Israel. They find these violations to be disproportional, primarily because there is a least restrictive alternative in the form of individualized assessments rather than the means the Act chose with is a blanket prohibition
Improving the outcomes of carotid endarterectomy: Results of a statewide quality improvement project
AbstractObjective: The purpose of this study was to establish the statewide outcomes for carotid endarterectomy (CEA) and to facilitate improvement in outcomes through feedback, peer discussion, and ongoing process and outcome measurement. Methods: The Medicare Part A claims files were used to identify all Medicare patients undergoing CEA in Iowa during two 12-month time periods (January 1994–December 1994 and June 1995–May 1996). Medical record abstraction was used to obtain surgical indications, perioperative care process, and outcome information. Confidential reports were provided to each hospital (N = 30) where the procedure was performed. Surgeons performing the procedure (N = 79) were invited to meetings to discuss care process variation and outcomes. Voluntary participation was solicited in a standardized program of ongoing hospital-based data collection of CEA process and outcome data. Results: The statewide combined stroke or mortality rate decreased from 7.8% in 1994 to 4.0% in the 1995 to 1996 time period (P <.001). Fourteen hospitals, accounting for 74% of the statewide cases, participated in ongoing data collection. The combined stroke or mortality rate in these hospitals decreased significantly (P <.05) over time from 6.5% (1994) to 3.7% (1995-1996) to 1.8% (June 1997–May 1998). The use of intraoperative assessment of the operative site (20% in 1994, 46% in 1997-1998) and patch angioplasty (14% in 1994, 30% in 1997-1998) increased significantly during this time in the participating hospitals. Conclusions: Confidential feedback of outcome and process data for CEA may lead to change in perioperative care processes and improved outcomes. Standardized community-based outcome analysis should become routine for CEA to ensure that optimum results are being achieved. (J Vasc Surg 2000;31:918-26.
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