Narrative Study of Teaching Strategies and Challenges Encountered by Teachers in Synchronous Online Classes

The COVID-19 pandemic urged a dramatic shift in the educational landscape, whereby digital platforms are utilized in teaching and learning. This new setup has posed challenges in teaching mathematics; hence, this study was conceptualized to explore the different teaching strategies and challenges math teachers encountered in their synchronous online classes (SOC). It aimed to draw analysis and increased understanding of the experiences related to teaching strategies and challenges, focusing on two essential aspects of teaching and learning: content and student engagement. Online in-depth interviews involving nine (9) Junior High School mathematics teachers of a private academic institution in Southern Luzon were conducted for data gathering. Results depict two significant themes as the participants' strategies in their SOC: teacher-directed instruction and motivational strategies.Meanwhile, three major themes emerged as challenges encountered by the participants: the role of the teacher, time constraints, and students' responsiveness. Findings suggest that some of the difficulties in synchronous online teaching may have resulted from the tendency to replicate face-to-face teaching in a virtual classroom and lack of technological proficiency. Hence, opportunities to enhance teachers’ knowledge and skills in digital pedagogies and more student-centered online teaching approaches can be a gateway to address the challenges posed

Two Dimensional Fractional Supersymmetry from the Quantum Poincare Group at Roots of Unity

A group theoretical understanding of the two dimensional fractional supersymmetry is given in terms of the quantum Poincare group at roots of unity. The fractional supersymmetry algebra and the quantum group dual to it are presented and the pseudo-unitary, irreducible representations of them are obtained. The matrix elements of these representations are explicitly constructed.Comment: 10 pages. Some misprints are corrected. To appear in J. Phys.

Bilan de l’azote et du phosphore dans les exploitations agricoles de la région de Thiès au Sénégal

Dans la zone des Niayes de Thiès au Sénégal, un système d’exploitation agricole intégrant l’agriculture et l’élevage est largement adopté. L’aviculture est généralement associée au maraîchage avec une utilisation simultanée des engrais chimiques et des déchets organiques issus des élevages. Le bilan des minéraux essentiels (azote et phosphore) à l’échelle de l’exploitation agricole et de ses indicateurs de fonctionnement ont été estimés à l’aide d’enquêtes et d’analyses de laboratoire. Les bilans positifs obtenus au niveau de toutes les exploitations prospectées ont montré des excédents d'azote (N) et de phosphore (P) élevés avec des valeurs moyennes de 1455,38 et 76,59 kg/ha/an, respectivement. Les pertes de N et de P sont importantes et restent indépendants de l’effectif des sujets. Les indicateurs de fonctionnement calculés pour l’azote et le phosphore traduisent leur mauvaise gestion dans les exploitations avec des indices de gaspillage respectifs de 12,74 et de 1,90 kg.Mot clés : Minéraux, indicateurs de fonctionnement, exploitations agricoles, Sénégal

Brain-vascular segmentation for SEEG planning via a 3D fully-convolutional neural network

Three dimensional visualization of vascular structures can assist clinicians in preoperative planning, intra-operative guidance, and post-operative decision-making. The goal of this work is to provide an automatic, accurate and fast method for brain vessels segmentation in Contrast Enhanced Cone Beam Computed Tomography (CE-CBCT) dataset based on a residual Fully Convolutional Neural Network (FCNN). The proposed NN embeds in an encoder-decoder architecture residual elements which decreases the vanishing effect due to deep architecture while accelerating the convergence. Moreover, a two-stage training has been proposed as a countermeasure for the unbalanced nature of the dataset. The FCNN training was performed on 20 CE-CBCT volumes exploiting mini-batch gradient descent andthe Adam optimizer. Binary cross-entropy was used as loss function. Performance evaluation was conducted considering 5 datasets. A median value of Dice, Precision and Recall of 0.79, 0.8 and 0.69 were obtained with respect to manual annotations

The rise and fall of Anopheles arabiensis (Diptera: Culicidae) in a Tanzanian village

The continual recruitment of new individuals makes it difficult to study both the survival of multivoltine mosquitoes, and the size of the infectious reservoir in narural populations of malaria vectors. During long-term surveillance of a population of Anopheles gambiae Giles sensu lato in a Tanzanian village by daily light trapping, a temporary dry spell resulted in the cessation of recruitment for a period of 33 days, and a decline in numbers of A. arabiensis Patton caught from over 2000 to less than 10 in a sentinel house. Traps placed elsewhere in the village indicated similar proportionate declines although numbers caught varied according to location. A survival rate of 83% per day was estimated from the rate of population decline. Survival was unrelated to the size of the mosquitoes. The infectious reservoir (the chance of a mosquito acquiring an infection) was estimated to be 2% per feed. The exploitation of fortuitous events which temporarily eliminate a single stage in the life cycle has general applicability in the study of the bionomics of multivoltine insect

The osteoporosis treatment gap in patients at risk of fracture in European primary care : a multi-country cross-sectional observational study

Summary This study in 8 countries across Europe found that about 75% of elderly women seen in primary care who were at high risk of osteoporosis-related fractures were not receiving appropriate medication. Lack of osteoporosis diagnosis appeared to be an important contributing factor. Introduction Treatment rates in osteoporosis are documented to be low. We wished to assess the osteoporosis treatment gap in women ≥ 70 years in routine primary care across Europe. Methods This cross-sectional observational study in 8 European countries collected data from women 70 years or older visiting their general practitioner. The primary outcome was treatment gap: the proportion who were not receiving any osteoporosis medication among those at increased risk of fragility fracture (using history of fracture, 10-year probability of fracture above country-specific Fracture Risk Assessment Tool [FRAX] thresholds, T-score ≤ − 2.5). Results Median 10-year probability of fracture (without bone mineral density [BMD]) for the 3798 enrolled patients was 7.2% (hip) and 16.6% (major osteoporotic). Overall, 2077 women (55%) met one or more definitions for increased risk of fragility fracture: 1200 had a prior fracture, 1814 exceeded the FRAX threshold, and 318 had a T-score ≤ − 2.5 (only 944 received a dual-energy x-ray absorptiometry [DXA] scan). In those at increased fracture risk, the median 10-year probability of hip and major osteoporotic fracture was 11.2% and 22.8%, vs 4.1% and 11.5% in those deemed not at risk. An osteoporosis diagnosis was recorded in 804 patients (21.2%); most (79.7%) of these were at increased fracture risk. The treatment gap was 74.6%, varying from 53% in Ireland to 91% in Germany. Patients with an osteoporosis diagnosis were found to have a lower treatment gap than those without a diagnosis, with an absolute reduction of 63%. Conclusions There is a large treatment gap in women aged ≥ 70 years at increased risk of fragility fracture in routine primary care across Europe. The gap appears to be related to a low rate of osteoporosis diagnosis

In vitro culture with gemcitabine augments death receptor and NKG2D ligand expression on tumour cells

Much effort has been made to try to understand the relationship between chemotherapeutic treatment of cancer and the immune system. Whereas much of that focus has been on the direct effect of chemotherapy drugs on immune cells and the release of antigens and danger signals by malignant cells killed by chemotherapy, the effect of chemotherapy on cells surviving treatment has often been overlooked. In the present study, tumour cell lines: A549 (lung), HCT116 (colon) and MCF-7 (breast), were treated with various concentrations of the chemotherapeutic drugs cyclophosphamide, gemcitabine (GEM) and oxaliplatin (OXP) for 24 hours in vitro. In line with other reports, GEM and OXP upregulated expression of the death receptor CD95 (fas) on live cells even at sub-cytotoxic concentrations. Further investigation revealed that the increase in CD95 in response to GEM sensitised the cells to fas ligand treatment, was associated with increased phosphorylation of stress activated protein kinase/c-Jun N-terminal kinase and that other death receptors and activatory immune receptors were co-ordinately upregulated with CD95 in certain cell lines. The upregulation of death receptors and NKG2D ligands together on cells after chemotherapy suggest that although the cells have survived preliminary treatment with chemotherapy they may now be more susceptible to immune cell-mediated challenge. This re-enforces the idea that chemotherapy-immunotherapy combinations may be useful clinically and has implications for the make-up and scheduling of such treatments