Isogeny graphs of ordinary abelian varieties

Fix a prime number $\ell$. Graphs of isogenies of degree a power of $\ell$ are well-understood for elliptic curves, but not for higher-dimensional abelian varieties. We study the case of absolutely simple ordinary abelian varieties over a finite field. We analyse graphs of so-called $\mathfrak l$-isogenies, resolving that they are (almost) volcanoes in any dimension. Specializing to the case of principally polarizable abelian surfaces, we then exploit this structure to describe graphs of a particular class of isogenies known as $(\ell, \ell)$-isogenies: those whose kernels are maximal isotropic subgroups of the $\ell$-torsion for the Weil pairing. We use these two results to write an algorithm giving a path of computable isogenies from an arbitrary absolutely simple ordinary abelian surface towards one with maximal endomorphism ring, which has immediate consequences for the CM-method in genus 2, for computing explicit isogenies, and for the random self-reducibility of the discrete logarithm problem in genus 2 cryptography.Comment: 36 pages, 4 figure

Computational Analyses of mRNA Ribosome Loading in Arabidopsis Thaliana

Translation of mRNA into protein is a critical step in gene expression, but the principles guiding its regulation at the genome level are not completely understood. Translation can be quantified at a genome scale by measuring the ribosome loading of mRNA—the extent to which mRNA is associated with ribosomes. In this dissertation, I present investigations into how genome-wide ribosome loading is controlled in Arabidopsis thaliana. In chapter 1, I give an overview of regulation of ribosome loading and translation. In chapter 2, I present research demonstrating for the first time that genome-wide ribosome loading in plants is partially controlled by the circadian clock. In chapter 3, I present a study of a computational model that describes how various biochemical steps control ribosome loading. And in chapter 4, I conclude by briefly summarizing the dissertation as a whole and discussing future perspectives

The Ursinus Weekly, January 27, 1911

Day of Prayer • To the memory of Robert Burns • Price football dinner • Alumni • Married • Society noteshttps://digitalcommons.ursinus.edu/weekly/2791/thumbnail.jp

Emergency care practitioners’ views on the use of ultrasound in pre-hospital acute care settings

Background: Ultrasound may assist in the detection of life-threatening conditions and evolving pathologies. South African emergency care practitioners (ECPs) working in pre-hospital contexts have historically not used ultrasound to diagnose and treat patients. However, recently published clinical practice guidelines from the Health Professions Council of South Africa (HPCSA) suggest that ultrasound be considered as an adjunct in the provision of pre-hospital emergency care. Our study investigated ECPs’ views and perceptions of introducing ultrasound to their scope of practice. Method: A qualitative prospective approach was followed, using semi-structured interviews with a purposefully selected sample of practising ECPs to investigate and describe their views and perceptions of the use of ultrasound in local pre-hospital emergency care contexts. The interviews were audio recorded and transcribed. Transcripts were critically read before being manually coded to identify core themes and categories. Results: ECPs recognise the potential value of ultrasound for a subset of patients within specific pre-hospital contexts. Concerns around the introduction of ultrasound as a diagnostic adjunct included the potential to create delays in treatment and transportation. Implementation challenges included cost implications and the need for additional education and training. Conclusion: ECPs practising in South African pre-hospital acute care contexts support the use of ultrasound, provided they are adequately trained, and its use does not lead to delays in treatment and arrival at receiving facilities. Additional training on the use of ultrasound may be necessary for ECPs. Further research is required to explore the benefits of ultrasound concerning patient-specific outcomes and the associated costs in resource-constrained pre-hospital emergency care settings

Sexual Dysfunction among Female Patients of Reproductive Age in a Hospital Setting in Nigeria

Although sexual dysfunction is an important public-health problem in Nigeria, little research has been conducted on this topic in Nigeria. This cross-sectional study was conducted to determine the prevalence of sexual dysfunction and their correlates among female patients of reproductive age using a questionnaire. Respondents were recruited from the out-patients clinics of a teaching hospital setting in Ile-Ife/Ijesa administrative health zone, Osun State, Nigeria. Of 384 female patients interviewed, 242 (63%) were sexually dysfunctional. Types of sexual dysfunction included disorder of desire (n=20; 8.3%), disorder of arousal (n=13; 5.4%), disorder of orgasm (n=154; 63.6%), and painful coitus (dyspareunia) (n=55; 22.7%). The peak age of sexual dysfunction was observed among the age-group of 26–30 years. Women with higher educational status were mostly affected. The reasons for unsatisfactory sexual life mainly included psychosexual factors and medical illnesses, among which included uncaring partners, present illness, excessive domestic duties, lack of adequate foreplay, present medication, competition among wives in a polygamous family setting, previous sexual abuse, and guilt-feeling of previous pregnancy termination among infertile women. The culture of male dominance in the local environment which makes women afraid of rejection and threats of divorce if they ever complain about sexually-related matters might perpetrate sexual dysfunction among the affected individuals. Sexual dysfunction is a real social and psychological problem in the local environment demanding urgent attention. It is imperative to carry out further research in society at large so that the health and lifestyles of affected women and their partners could be improved

On the design and implementation of efficient antennas for high frequency-radio frequency identification read/write devices

AbstractThis article describes an in‐depth methodical approach to the development of efficient high‐frequency (HF) antennas for use in radio frequency identification (RFID) systems operating at 13.56 MHz. It presents brief theory relevant to RFID communication and sets up a framework within which features and requirements of antennas are linked to key design parameters such as antenna form‐factor and size; RF power level, material and communication protocol. Tuning circuits necessary to adjust the resonance and power matching characteristics of antennas for good transponder interrogation and response recovery are discussed. To validate the approaches outlined, a stepwise design and measurement of an HF antenna for an ISO/IEC 15693 compliant read/write device (RWD) is described. Common practical problems that are often encountered in such design processes are also commented on. The prototyped antenna was tuned, connected to the RWD via a 50 coaxial cable and tested

The Effects of Sustained Gepirone Administration on Rodent Brain 5-HT Receptors and Behavioral Analogues of Anxiety

Clinical evidence has demonstrated that the anxiolytic effects produced by the selective 5-hydroxytryptamine1A (5-HT1A) receptor agonist, gepirone, increase progressively over one to three weeks of treatment

Echocardiography Core Laboratory Validation of a Novel Vendor-Independent Web-Based Software for the Assessment of Left Ventricular Global Longitudinal Strain

BACKGROUND: Global longitudinal strain (GLS) is an accurate and reproducible parameter of left ventricular (LV) systolic function which has shown meaningful prognostic value. Fast, user-friendly, and accurate tools are required for its widespread implementation. We aim to compare a novel web-based tool with two established algorithms for strain analysis and test its reproducibility. METHODS: Thirty echocardiographic datasets with focused LV acquisitions were analyzed using three different semi-automated endocardial GLS algorithms by two readers. Analyses were repeated by one reader for the purpose of intra-observer variability. CAAS Qardia (Pie Medical Imaging) was compared with 2DCPA and AutoLV (TomTec). RESULTS: Mean GLS values were −15.0 ± 3.5% from Qardia, −15.3 ± 4.0% from 2DCPA, and −15.2 ± 3.8% from AutoLV. Mean GLS between Qardia and 2DCPA were not statistically different (p = 0.359), with a bias of −0.3%, limits of agreement (LOA) of 3.7%, and an intraclass correlation coefficient (ICC) of 0.88. Mean GLS between Qardia and AutoLV were not statistically different (p = 0.637), with a bias of −0.2%, LOA of 3.4%, and an ICC of 0.89. The coefficient of variation (CV) for intra-observer variability was 4.4% for Qardia, 8.4% 2DCPA, and 7.7% AutoLV. The CV for inter-observer variability was 4.5%, 8.1%, and 8.0%, respectively. CONCLUSIONS: In echocardiographic datasets of good image quality analyzed at an independent core laboratory using a standardized annotation method, a novel web-based tool for GLS analysis showed consistent results when compared with two algorithms of an established platform. Moreover, inter- and intra-observer reproducibility results were excellent.</p