Historical and literary influences on Tsarfati’s "Poem composed by the Poet upon his translation of the tale of Melibea and Calisto"

This article presents a literary analysis of the extant poetic prologue to the Hebrew adaptation of Celestina, written in Italy by Joseph ben Samuel Tsarfati at the beginning of the 16th century. The prologue is shown to be a product of various literary traditions, and an indication of the nature of the role of secular literature within the Jewish literary corpus. The poet reconciles and juxtaposes his literary inspiration, Celestina, and secular literary conceits with the conventions and character of Medieval Hebrew literature

Perfectionism and exam performance: The mediating effect of task-approach goals

Perfectionistic strivings are positively correlated with students’ achievement goals and exam performance. However, so far no study has employed a prospective design investigating whether achievement goals mediate the positive relationship between perfectionistic strivings and exam performance. In the present study, 100 university students completed a measure of self-oriented perfectionism and socially prescribed perfectionism (Hewitt & Flett, 1991) and received a chapter from a textbook to study for 2-4 days. Then they returned to the lab to complete a measure of achievement goals following the 3 x 2 model (Elliot, Murayama, & Pekrun, 2011) and sit a mock exam testing their knowledge of the chapter. Multiple regressions showed that socially prescribed perfectionism negatively predicted exam performance when the overlap with self-oriented perfectionism was controlled for. In contrast, self-oriented perfectionism—a defining indicator of perfectionistic strivings—positively predicted exam performance. Moreover, task-approach goals mediated the positive relationship between self-oriented perfectionism and exam performance. The findings suggest that perfectionistic strivings make students adopt task-approach goals that help them achieve better results on exams

Hydrophobic and Charged Residues in the C-Terminal Arm of Hepatitis C Virus RNA-Dependent RNA Polymerase Regulate Initiation and Elongation.

The RNA-dependent RNA polymerase (RdRp) of hepatitis C virus (HCV) is essential for viral genome replication. Crystal structures of the HCV RdRp reveal two C-terminal features, a β-loop and a C-terminal arm, suitably located for involvement in positioning components of the initiation complex. Here we show that these two elements intimately regulate template and nucleotide binding, initiation, and elongation. We constructed a series of β-loop and C-terminal arm mutants, which were used for in vitro analysis of RdRp de novo initiation and primer extension activities. All mutants showed a substantial decrease in initiation activities but a marked increase in primer extension activities, indicating an ability to form more stable elongation complexes with long primer-template RNAs. Structural studies of the mutants indicated that these enzyme properties might be attributed to an increased flexibility in the C-terminal features resulting in a more open polymerase cleft, which likely favors the elongation process but hampers the initiation steps. A UTP cocrystal structure of one mutant shows, in contrast to the wild-type protein, several alternate conformations of the substrate, confirming that even subtle changes in the C-terminal arm result in a more loosely organized active site and flexible binding modes of the nucleotide. We used a subgenomic replicon system to assess the effects of the same mutations on viral replication in cells. Even the subtlest mutations either severely impaired or completely abolished the ability of the replicon to replicate, further supporting the concept that the correct positioning of both the β-loop and C-terminal arm plays an essential role during initiation and in HCV replication in general. IMPORTANCE: HCV RNA polymerase is a key target for the development of directly acting agents to cure HCV infections, which necessitates a thorough understanding of the functional roles of the various structural features of the RdRp. Here we show that even highly conservative changes, e.g., Tyr→Phe or Asp→Glu, in these seemingly peripheral structural features have profound effects on the initiation and elongation properties of the HCV polymerase

Application of Unmanned Aerial Vehicles in Emergency Medical Situations

Introduction One of the significant impacts on patient outcome in emergency medical situations is the response time taken for trained personnel and equipment arrival on scene. The National EMS Information System states the average response time to reach adult patients in the United States is 9.4 minutes (1). We are exploring the whether the application of Unmanned Aerial Vehicle (UAV) technology in emergency situations would shorten response time and subsequently could improve patients’ outcome In this reported on first phase (Phase 1) of an envisioned multi-stage project, we tested the ability of a UAV to properly, efficiently transport a a portable ECG device to a mock emergency site and successfully take an ECG reading when used by an untrained personnel on hand. MethodsOur UAV was a DJI Phantom 2 Vision model, a quadcopter equipped with a 14 Megapixel camera and HD video recording capabilities. The onboard camera allows for real time transmission of patient status and appearance, while the quadcopter model allows for maximum weight to lift ratio. In order to record a portable ECG, we equipped an iPhone 5 with an AliveCor Kardia mobile ECG monitor. We included an easy to use protocol for the AliveCor so that a layperson would be able to operate the machine. DataThe total flight time for 100 yards across an open field was two and a half minutes , or approximately 2 feet/second. This data shows a chi-squared distribution of 5.065, with a p-value of .01 (df=1, p\u3c.05). DiscussionDue to the statistically significant p-value, Phase 1 data demonstrates that our UAV was capable of traversing an appropriate distance in an amount of time that drastically improves upon the emergency response call time taken by traditional methods. In addition to our flight data, we were also able to properly operate the ECG and apply it to a mock patient in under 90 seconds, showing that our protocol, with instructions for usage, was clear and precise. Conclusion: This study is considered Phase 1 of a multi-stage investigation. Moving forward, we hope to improve the efficacy of our UAV, while expanding its the technological and medical capabilities, allowing it to not only carry ECG but also possibly AEDs and pharmaceuticals. Ultimately, We hope to apply such technology to emergencies in both rural and urban environments, as well as adapt it for use within the military

Calcium supplements and risk of CVD: A meta-analysis of randomized trials

Background: Vitamin D supplements may only be beneficial for the prevention of osteoporotic fractures when administered with calcium and in individuals with low blood levels of 25(OH)D, but possible hazards of calcium supplements on CVD cannot be excluded. Objectives: We conducted a meta-analysis of all placebo-controlled randomized trials assessing the effects of calcium supplements alone or with vitamin D on CHD, stroke, and all-cause mortality. Methods: A meta-analysis of 11 trials included 7 comparisons of calcium alone compared with control (n = 8634) and 6 comparisons of calcium plus vitamin D compared with control (n = 46,804). Aggregated study-level data were obtained from individual trials and combined using a fixed-effects meta-analysis. The main outcomes included MI, CHD death, any CHD, stroke, and all-cause mortality. Results: Among trials of calcium alone (mean daily dose 1 g), calcium was not significantly associated with any excess risk of MI (RR, 1.15; 95% CI: 0.88, 1.51; n = 219 events), CHD death (RR, 1.24; 95% CI: 0.89, 1.73; n = 142), any CHD (RR, 1.01; 95% CI: 0.75, 1.37; n = 177), or stroke (RR, 1.15; 95% CI, 0.90, 1.46, n = 275). Among 6 trials of combined treatment, supplementation with calcium plus vitamin D was not significantly associated with any excess risk of MI (RR, 1.09; 95% CI: 0.95, 1.25; n = 854), CHD death (RR, 1.04; 95% CI: 0.85, 1.27; n = 391), any CHD (RR, 1.05; 95% CI: 0.93, 1.19; n = 1061), or stroke (RR, 1.02; 95% CI: 0.89, 1.17; n = 885). Likewise, calcium alone, or with vitamin D had no significant associations with all-cause mortality. Conclusions: This meta-analysis demonstrated that calcium supplements were not associated with any significant hazard for CHD, stroke, or all-cause mortality and excluded excess risks above 0.3%–0.5% per year for CHD or stroke. Further trials of calcium and vitamin D are required in individuals with low blood levels of 25(OH)D for the prevention of fracture and other disease outcomes

Prediagnostic use of hormone therapy and mortality after breast cancer.

BACKGROUND: A few studies have observed reduced breast cancer mortality in women who used hormone therapy before diagnosis. Due to the high prevalence of past and current hormone use, it is important to investigate whether these preparations are related to breast cancer mortality. METHODS: To evaluate the influence of prediagnostic use of hormone therapy on breast cancer mortality, a prospective cohort of 12,269 women ages 50 years or more diagnosed with incident invasive breast cancer and residents of Wisconsin, Massachusetts, or New Hampshire were enrolled in three phases beginning in 1988. They were followed for death until December 31, 2005, using the National Death Index. Cumulative mortality and multivariable adjusted hazard rate ratios for breast cancer and other mortality causes were calculated for women according to any hormone therapy use, and for exclusive use of estrogen or estrogen-progestin (EP). RESULTS: During an average 10.3 years of follow-up, 1,690 deaths from breast cancer were documented. Cumulative mortality from breast cancer was lower among hormone therapy users, specifically current users at the time of diagnosis, and EP users, compared with nonusers. Adjusted survival varied by type and duration of hormone therapy before diagnosis. A reduced risk of death from breast cancer was associated with EP preparations (hazard rate ratio, 0.73; 0.59-0.91) and with > or =5 years of EP use (0.60; 0.43-0.84). No association was observed for women who were former or current users of E-alone preparations. CONCLUSIONS: Although use of combined EP preparations increases breast cancer risk, in this study, use of these hormones before diagnosis was associated with reduced risk of death after a breast cancer diagnosis. The better survival among users, particularly of EP, persisted after adjustment of screening, stage, and measured confounders

Cigarette Smoking Before and After Breast Cancer Diagnosis: Mortality From Breast Cancer and Smoking-Related Diseases

Cigarette smoking increases overall mortality, but it is not established whether smoking is associated with breast cancer prognosis

The case for altruism in institutional diagnostic testing

Amid COVID-19, many institutions deployed vast resources to test their members regularly for safe reopening. This self-focused approach, however, not only overlooks surrounding communities but also remains blind to community transmission that could breach the institution. To test the relative merits of a more altruistic strategy, we built an epidemiological model that assesses the differential impact on case counts when institutions instead allocate a proportion of their tests to members\u27 close contacts in the larger community. We found that testing outside the institution benefits the institution in all plausible circumstances, with the optimal proportion of tests to use externally landing at 45% under baseline model parameters. Our results were robust to local prevalence, secondary attack rate, testing capacity, and contact reporting level, yielding a range of optimal community testing proportions from 18 to 58%. The model performed best under the assumption that community contacts are known to the institution; however, it still demonstrated a significant benefit even without complete knowledge of the contact network