Electric and Magnetic fields due to Dirac particles in FRW spacetime

Some solutions of the Maxwell equations with Dirac particles for the source in FRW spacetime are discussed. The Green's function of the equation for the radial component of the Maxwell fields, F_{r\eta} and F_{\theta\phi} is solved. Green's function is found to reduce to that of Minkowskian spacetime in the appropriate limit. Also, the Lienard-Wiechert type solution is derived. Also, the solutions with the Dirac particle current is also presented. It is found that the F_{r\eta} is composed of even angular momentum states while the odd states constitue F_{\theta\phi} .Comment: 8 pages including 2 figure

Why are so many Nepali women killing themselves? A review of key issues

Background: For decades the maternal mortality in Nepal was the lead cause of death among women, with great improvements in the maternal mortality ratio in the twentieth century the second most common cause has become more prominent. Suicide is now one of the leading causes of death for women of a reproductive age in Nepal. This scoping review brings together the key available literature to identify the causes of suicide among women in Nepal. Methods: Published and unpublished studies and the grey literature published on women and suicide related to Nepal between 2000 and 2014 were searched and included in this review. Results: This review suggested a number of explanations for the high rate of suicide among women including: partner violence, alcoholism and polygamy, the culture of silence, early age marriage and prolonged child bearing and dependency on men for financial security. Conclusion: This paper highlights some challenges and suggests ways forward in the improvement of mental health in Nepal

Factors affecting the uptake of institutional delivery, antenatal and postnatal care in Nawalparasi district, Nepal

© 2019, Kathmandu University. All rights reserved. Background Maternal deaths and complications are highly preventable with good antenatal, postnatal and skilled care during childbirth. Inadequate information on the factors affecting these services could be barrier to a reduction of maternal deaths in low-income countries. Objective To assess the uptake of antenatal, postnatal and skilled care during childbirth. Method A cross-sectional study was conducted in eight villages of Nawalparasi district in southern Nepal. A total of 447 women who had given birth within the preceding 24 months were recruited using multistage random sampling. Data were collected using a pre-tested semi-structured questionnaire. Chi-square tests were used to assess association between variables. Result Over 70% of women had gone for at least four antenatal care check-ups while only 14.3% had at least three postnatal check-ups in their last pregnancies. The proportion of institution delivery was 54%. Women’s literacy was associated with the uptake of antenatal services (p=<0.001), postnatal care (p=0.04) and institutional delivery (p=<0.001). Knowledge of antenatal (p=<0.001) and postnatal care was also associated with uptake of respective services (p=<0.001). Conclusion The uptake and knowledge of antenatal care was much better than of postnatal care. Home delivery rates were still very high. A scaling-up of education and awareness-raising interventions in this community could help improve the uptake of maternal health services

Brain-Inspired Reservoir Computing Using Memristors with Tunable Dynamics and Short-Term Plasticity

Recent advancements in reservoir computing research have created a demand for analog devices with dynamics that can facilitate the physical implementation of reservoirs, promising faster information processing while consuming less energy and occupying a smaller area footprint. Studies have demonstrated that dynamic memristors, with nonlinear and short-term memory dynamics, are excellent candidates as information-processing devices or reservoirs for temporal classification and prediction tasks. Previous implementations relied on nominally identical memristors that applied the same nonlinear transformation to the input data, which is not enough to achieve a rich state space. To address this limitation, researchers either diversified the data encoding across multiple memristors or harnessed the stochastic device-to-device variability among the memristors. However, this approach requires additional pre-processing steps and leads to synchronization issues. Instead, it is preferable to encode the data once and pass it through a reservoir layer consisting of memristors with distinct dynamics. Here, we demonstrate that ion-channel-based memristors with voltage-dependent dynamics can be controllably and predictively tuned through voltage or adjustment of the ion channel concentration to exhibit diverse dynamic properties. We show, through experiments and simulations, that reservoir layers constructed with a small number of distinct memristors exhibit significantly higher predictive and classification accuracies with a single data encoding. We found that for a second-order nonlinear dynamical system prediction task, the varied memristor reservoir experimentally achieved a normalized mean square error of 0.0015 using only five distinct memristors. Moreover, in a neural activity classification task, a reservoir of just three distinct memristors experimentally attained an accuracy of 96.5%

From Rags to Riches: Assessing poverty and vulnerability in urban Nepal

Urbanisation brings with it rapid socio-economic change with volatile livelihoods and unstable ownership of assets. Yet, current measures of wealth are based predominantly on static livelihoods found in rural areas. We sought to assess the extent to which seven common measures of wealth appropriately capture vulnerability to poverty in urban areas. We then sought to develop a measure that captures the characteristics of one urban area in Nepal. We collected and analysed data from 1,180 households collected during a survey conducted between November 2017 and January 2018 and designed to be representative of the Kathmandu valley. A separate survey of a sub set of households was conducted using participatory qualitative methods in slum and non-slum neighbourhoods. A series of currently used indices of deprivation were calculated from questionnaire data. We used bivariate statistical methods to examine the association between each index and identify characteristics of poor and non-poor. Qualitative data was used to identify characteristics of poverty from the perspective of urban poor communities which were used to construct an Urban Poverty Index that combined asset and consumption focused context specific measures of poverty that could be proxied by easily measured indicators as assessed through multivariate modelling. We found a strong but not perfect association between each measure of poverty. There was disagreement when comparing the consumption and deprivation index on the classification of 19% of the sample. Choice of short-term monetary and longer-term capital approaches accounted for much of the difference. Those who reported migrating due to economic necessity were most likely to be categorised as poor. A combined index was developed to capture these dimension of poverty and understand urban vulnerability. A second version of the index was constructed that can be computed using a smaller range of variables to identify those in poverty. Current measures may hide important aspects of urban poverty. Those who migrate out of economic necessity are particularly vulnerable. A composite index of socioeconomic status helps to capture the complex nature of economic vulnerability

Signed Laplacian Deep Learning with Adversarial Augmentation for Improved Mammography Diagnosis

Computer-aided breast cancer diagnosis in mammography is limited by inadequate data and the similarity between benign and cancerous masses. To address this, we propose a signed graph regularized deep neural network with adversarial augmentation, named \textsc{DiagNet}. Firstly, we use adversarial learning to generate positive and negative mass-contained mammograms for each mass class. After that, a signed similarity graph is built upon the expanded data to further highlight the discrimination. Finally, a deep convolutional neural network is trained by jointly optimizing the signed graph regularization and classification loss. Experiments show that the \textsc{DiagNet} framework outperforms the state-of-the-art in breast mass diagnosis in mammography.Comment: To appear in MICCAI October 201

When left ventricular failure complicates chronic obstructive pulmonary disease: Hypoxia plays the major role

Abstract Introduction: As the chronic obstructive pulmonary disease (COPD) progress, is usually accompanied by involvement of the both left ventricle (LV) and right ventricle (RV), and their systolic and diastolic function. Signs and symptoms of LV failure can be difficult to distinguish from those of COPD. Objective: The study was carried out to determine the prevalence of LV systolic dysfunction in the COPD patients and to assess the possible risk factor behind such development. Material and Methods: It is a prospective study of 60 cases of COPD patients with or without cor-pulmonale attending Manipal Teaching Hospital. Results: The prevalence of LV systolic dysfunction was found to be 26.7%, and the findings directly correlate with the severity of COPD i.e., the more the severity of the lung disease more the probability for the incidence of LV systolic dysfunction. These data are in support of the hypothesis that hypoxia and the excess accumulation of toxic metabolic products like lactic acid, significant right-to-left shunting through the bronchial circulation explains the diminished LV ejection fraction in severe COPD patients. Conclusion: Routine echocardiography investigation of the severe COPD patients is required for assessing the status of LV function and to rule out the possible association of LV systolic dysfunction. Key words: Chronic obstructive pulmonary disease, Cor-pulmonale, Hypoxia, LV systolic dysfunction hronic obstructive pulmonary disease (COPD) is a disease state characterized by the presence of airflow obstruction due to chronic bronchitis or emphysema which is progressive and is partially reversible. Right ventricular (RV) hypertrophy and dilatation secondary to pulmonary hypertension caused by COPD (i.e., cor pulmonale) is unrelated to the left side of the heart. With RV pressure overload, the septum tends to be displaced toward the left ventricle (LV) during systole, which causes a distortion of the LV 1 . Since the myocardial fibres of the RV free walls are connected with those of the septum and LV free wall, a pressure increase in the RV is accompanied by changes in the LV systolic function 2 . This might be a partial explanation for the LV involvement in the course of COPD, causing an increased morbidity and mortality of ischemic heart disease and LV dysfunction 3 . Understanding the relationship between RV hypertrophy and LV systolic function in patients with COPD will be helpful for the better patient management. Objective The main objective of this study is to determine the prevalence of LV systolic dysfunction in the COPD patients and to assess the possible risk factor behind such development

A comprehensive and version-controlled database of glacial lake outburst floods in High Mountain Asia

Glacial lake outburst floods (GLOFs) have been intensely investigated in High Mountain Asia (HMA) in recent years and are the most well-known hazard associated with the cryosphere. As glaciers recede and surrounding slopes become increasingly unstable, such events are expected to increase, although current evidence for an increase in events is ambiguous. Many studies have investigated individual events, and while several regional inventories exist, they either do not cover all types of GLOF or are geographically constrained. Further, downstream impacts are rarely discussed. Previous inventories have relied on academic sources and have not been combined with existing inventories of glaciers and lakes. In this study, we present the first comprehensive inventory of GLOFs in HMA, including details on the time of their occurrence, processes of lake formation and drainage involved, and downstream impacts. We document 697 individual GLOFs that occurred between 1833 and 2022. Of these, 23 % were recurring events from just three ephemeral ice-dammed lakes. In combination, the documented events resulted in 6906 fatalities of which 906 can be attributed to 24 individual GLOF events, which is 3 times higher than a previous assessment for the region. The integration of previous inventories of glaciers and lakes within this database will inform future assessments of potential drivers of GLOFs, allowing more robust projections to be developed. The database and future, updated versions are traceable and version-controlled and can be directly incorporated into further analysis. The database is available at https://doi.org/10.5281/zenodo.7271187 (Steiner and Shrestha, 2023), while the code including a development version is available on GitHub.</p