Effects of homeostatic constraints on associative memory storage and synaptic connectivity of cortical circuits

The impact of learning and long-term memory storage on synaptic connectivity is not completely understood. In this study, we examine the effects of associative learning on synaptic connectivity in adult cortical circuits by hypothesizing that these circuits function in a steady-state, in which the memory capacity of a circuit is maximal and learning must be accompanied by forgetting. Steady-state circuits should be characterized by unique connectivity features. To uncover such features we developed a biologically constrained, exactly solvable model of associative memory storage. The model is applicable to networks of multiple excitatory and inhibitory neuron classes and can account for homeostatic constraints on the number and the overall weight of functional connections received by each neuron. The results show that in spite of a large number of neuron classes, functional connections between potentially connected cells are realized with less than 50% probability if the presynaptic cell is excitatory and generally a much greater probability if it is inhibitory. We also find that constraining the overall weight of presynaptic connections leads to Gaussian connection weight distributions that are truncated at zero. In contrast, constraining the total number of functional presynaptic connections leads to non-Gaussian distributions, in which weak connections are absent. These theoretical predictions are compared with a large dataset of published experimental studies reporting amplitudes of unitary postsynaptic potentials and probabilities of connections between various classes of excitatory and inhibitory neurons in the cerebellum, neocortex, and hippocampus

Rare case of Hirayama’s disease

Hirayama’s disease is a rare benign neurological disorder also known as monomelic amyotrophy, Sobue disease,Juvenile Muscular Atrophy of Distal Upper Extremity (JMADUE). It mainly affects young males in their second or third decades and is most commonly seen in Asian countries like Japan, Malaysia and India. In majority of the cases the cause of the disease is unknown. An 18 year male came with weakness in his right hand and forearm since 1 year. Examination revealed weakness and wasting of muscles of forearm and hand without lower limb involvement and normal deep tendon reflexes. MRI showed focal short segment hyperintense signal in the ventral and right lateral aspect of the cervical cord at C5-C6 level with the involved segment measuring 4x3mm in size. Based on clinical and radiological features a diagnosis of focal amyotrophy was made. Patient is given a cervical collar to prevent flexion at the neck and physiotherapy in the form of hand and forearm exercises were started. Regular follow up of the patient once every 2 months is being done. Hirayama’s disease is a rare, benign, self-limiting neurological disorder. Early diagnosis and management by preventing cervical flexion with the help of a cervical collar has shown to halt the progression of the disease

Optimasi Portofolio Resiko Menggunakan Model Markowitz MVO Dikaitkan dengan Keterbatasan Manusia dalam Memprediksi Masa Depan dalam Perspektif Al-Qur`an

Risk portfolio on modern finance has become increasingly technical, requiring the use of sophisticated mathematical tools in both research and practice. Since companies cannot insure themselves completely against risk, as human incompetence in predicting the future precisely that written in Al-Quran surah Luqman verse 34, they have to manage it to yield an optimal portfolio. The objective here is to minimize the variance among all portfolios, or alternatively, to maximize expected return among all portfolios that has at least a certain expected return. Furthermore, this study focuses on optimizing risk portfolio so called Markowitz MVO (Mean-Variance Optimization). Some theoretical frameworks for analysis are arithmetic mean, geometric mean, variance, covariance, linear programming, and quadratic programming. Moreover, finding a minimum variance portfolio produces a convex quadratic programming, that is minimizing the objective function ðð¥with constraintsð ð 𥠥 ðandð´ð¥ = ð. The outcome of this research is the solution of optimal risk portofolio in some investments that could be finished smoothly using MATLAB R2007b software together with its graphic analysis

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Search for supersymmetry in events with one lepton and multiple jets in proton-proton collisions at root s=13 TeV

Peer reviewe

Search for anomalous couplings in boosted WW/WZ -> l nu q(q)over-bar production in proton-proton collisions at root s=8TeV

Peer reviewe

Cell type matching in single-cell RNA-sequencing data using FR-Match

Reference cell atlases powered by single cell and spatial transcriptomics technologies are becoming available to study healthy and diseased tissue at single cell resolution. One important use of these data resources is to compare cell types from new dataset with cell types in the reference atlases to evaluate their phenotypic similarities and differences, for example, for identifying novel cell types under disease conditions. For this purpose, rigorously-validated computational algorithms are needed to perform these cell type matching tasks that can compare datasets from different experiment platforms and sample types. Here, we present significant enhancements to FR-Match (v2.0)-a multivariate nonparametric statistical testing approach for matching cell types in query datasets to reference atlases. FR-Match v2.0 includes a normalization procedure to facilitate cross-platform cluster-level comparisons (e.g., plate-based SMART-seq and droplet-based 10X Chromium single cell and single nucleus RNA-seq and spatial transcriptomics) and extends the pipeline to also allow cell-level matching. In the use cases evaluated, FR-Match showed robust and accurate performance for identifying common and novel cell types across tissue regions, for discovering sub-optimally clustered cell types, and for cross-platform and cross-sample cell type matching

Correlation of Inflammation and Anemia in Patients on Hemodialysis

Introduction: Anemia and inflammation are majorly observed complications in patients on hemodialysis (HD). Present study assessed that inflammation that affects the haemoglobin levels in patients with chronic kidney disease (CKD) stage 5 on maintenance HD and to evaluate the degree of anemia.Methods: A retrospective observational study was conducted in CKD patients aged 18-89 years. Previous hospital records were reviewed to note baseline clinical co-morbidities, pre- and post HD -session body weight, dialyzer type, blood flow rate, dialysis time, dialysis prescription (dry body weight, dialysis time, dialysis modality, and dialysate and heparin dose). Results: Out of 46 patients on HD, 31 and 15 were dialyzed with the arteriovenous fistula (AVF) and tunneled cuffed catheters (CTC), respectively. The mean age was 54.59 years and majority had diabetic nephropathy (39.1%). Patients of AVF group showed decreased c-reactive protein (CRP) levels [10.49 (13.25) Vs 26.69 (20.0) mg/L] and higher dialysis vintage (35.50 vs. 15.07 days) as compared to CTC group. A significant negative correlation of CRP with hemoglobin (p<0.0001) and serum albumin (p=0.0005) was observed. CRP levels showed a positive correlation with erythropoietin resistance index (ERI) (p=0.0025). The mean serum CRP levels in patients having hypoalbuminemia (28.87 mg/L) were significantly elevated as compared with patients with normoalbuminemia (10.61 mg/L) (p<0.001). The mean ERI in patients with parathyroid hormone (PTH) value >300 pg/mL was comparatively higher (17.85) as compared to patients with PTH value <300 pg/mL (12.46).Conclusion: Reduced inflammation improves anemia and nutritional status of patients on HD. AVF should be considered as first option for dialysis access