Anil Thapa
Tribhuvan University, BSC Csit, Undergraduate
We present a model of radiative neutrino masses which also resolves anomalies reported in B-meson decays, $$ {R}_{D^{\left(\ast \right)}} $$ R D ∗ and $$ {R}_{K^{\left(\ast \right)}} $$ R K ∗ , as well as in muon g − 2 measurement, ∆aμ.... more
We present a model of radiative neutrino masses which also resolves anomalies reported in B-meson decays, $$ {R}_{D^{\left(\ast \right)}} $$ R D ∗ and $$ {R}_{K^{\left(\ast \right)}} $$ R K ∗ , as well as in muon g − 2 measurement, ∆aμ. Neutrino masses arise in the model through loop diagrams involving TeV-scale leptoquark (LQ) scalars R2 and S3. Fits to neutrino oscillation parameters are obtained satisfying all flavor constraints which also explain the anomalies in $$ {R}_{D^{\left(\ast \right)}} $$ R D ∗ , $$ {R}_{K^{\left(\ast \right)}} $$ R K ∗ and ∆aμ within 1 σ. An isospin-3/2 Higgs quadruplet plays a crucial role in generating neutrino masses; we point out that the doubly-charged scalar contained therein can be produced in the decays of the S3 LQ, which enhances its reach to 1.1 (6.2) TeV at $$ \sqrt{s} $$ s = 14 TeV high-luminosity LHC ($$ \sqrt{s} $$ s = 100 TeV FCC-hh). We also present flavor-dependent upper limits on the Yukawa couplings of the LQs to the first two famil...
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The aim of this study was to compare costs and socio-economic impact of tuberculosis (TB) for patients diagnosed through active (ACF) and passive case finding (PCF) in Nepal. A longitudinal costing survey was conducted in four districts... more
The aim of this study was to compare costs and socio-economic impact of tuberculosis (TB) for patients diagnosed through active (ACF) and passive case finding (PCF) in Nepal. A longitudinal costing survey was conducted in four districts of Nepal from April 2018 to October 2019. Costs were collected using the WHO TB Patient Costs Survey at three time points: intensive phase of treatment, continuation phase of treatment and at treatment completion. Direct and indirect costs and socio-economic impact (poverty headcount, employment status and coping strategies) were evaluated throughout the treatment. Prevalence of catastrophic costs was estimated using the WHO threshold. Logistic regression and generalized estimating equation were used to evaluate risk of incurring high costs, catastrophic costs and socio-economic impact of TB over time. A total of 111 ACF and 110 PCF patients were included. ACF patients were more likely to have no education (75% vs 57%, P = 0.006) and informal employm...
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Models of radiative Majorana neutrino masses require new scalars and/or fermions to induce lepton-number-violating interactions. We show that these new particles also generate observable neutrino non-standard interactions (NSI) with... more
Models of radiative Majorana neutrino masses require new scalars and/or fermions to induce lepton-number-violating interactions. We show that these new particles also generate observable neutrino non-standard interactions (NSI) with matter. We classify radiative models as type-I or II, with type-I models containing at least one Standard Model (SM) particle inside the loop diagram generating neutrino mass, and type- II models having no SM particle inside the loop. While type-II radiative models do not generate NSI at tree-level, popular models which fall under the type-I category are shown, somewhat surprisingly, to generate observable NSI at tree-level, while being consistent with direct and indirect constraints from colliders, electroweak precision data and charged-lepton flavor violation (cLFV). We survey such models where neutrino masses arise at one, two and three loops. In the prototypical Zee model which generates neutrino masses via one-loop diagrams involving charged scalars...
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This report summarizes the present status of neutrino non-standard interactions (NSI). After a brief overview, several aspects of NSIs are discussed, including connection to neutrino mass models, model-building and phenomenology of large... more
This report summarizes the present status of neutrino non-standard interactions (NSI). After a brief overview, several aspects of NSIs are discussed, including connection to neutrino mass models, model-building and phenomenology of large NSI with both light and heavy mediators, NSI phenomenology in both short- and long-baseline neutrino oscillation experiments, neutrino cross-sections, complementarity of NSI with other low- and high-energy experiments, fits with neutrino oscillation and scattering data, DUNE sensitivity to NSI, effective field theory of NSI, as well as the relevance of NSI to dark matter and cosmology. We also discuss the open questions and interesting future directions that can be pursued by the community at large. This report is based on talks and discussions during the Neutrino Theory Network NSI workshop held at Washington University in St.~Louis from May 29-31, 2019
Background The World Health Organization (WHO) End TB Strategy has established a milestone to reduce the number of tuberculosis (TB)- affected households facing catastrophic costs to zero by 2020. The role of active case finding (ACF) in... more
Background The World Health Organization (WHO) End TB Strategy has established a milestone to reduce the number of tuberculosis (TB)- affected households facing catastrophic costs to zero by 2020. The role of active case finding (ACF) in reducing patient costs has not been determined globally. This study therefore aimed to compare costs incurred by TB patients diagnosed through ACF and passive case finding (PCF), and to determine the prevalence and intensity of patient-incurred catastrophic costs in Nepal. Methods The study was conducted in two districts of Nepal: Bardiya and Pyuthan (Province No. 5) between June and August 2018. One hundred patients were included in this study in a 1:1 ratio (PCF: ACF, 25 consecutive ACF and 25 consecutive PCF patients in each district). The WHO TB patient costing tool was applied to collect information from patients or a member of their family regarding indirect and direct medical and non-medical costs. Catastrophic costs were calculated based on ...
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Background Healthcare centers are important sites for tuberculosis transmission, particularly in low-income settings where the burden of tuberculosis is high and infection control practices are often inadequate. This study aims to assess... more
Background Healthcare centers are important sites for tuberculosis transmission, particularly in low-income settings where the burden of tuberculosis is high and infection control practices are often inadequate. This study aims to assess the knowledge, attitude, and practices of drug-resistant tuberculosis infection control among the healthcare workers under the National Tuberculosis Control Program in Nepal. Methods In this descriptive cross-sectional survey, we studied the healthcare workers from all the functioning drug-resistant tuberculosis treatment centers across Nepal between March 1, 2018 and March 15, 2018. Nepal Health Research Council provided ethical clearance. Trained enumerators obtained informed consent and conducted face-to-face interviews with a pretested questionnaire to collect data on the basic characteristics of healthcare workers, their self-reported knowledge, attitude, and practice on tuberculosis infection control. We assigned a score of one to the correct ...
The objective of the present in vitro study was to determine vascular endothelial and smooth muscle cell responses to poly(lactic-co-glycolic acid) (PLGA) films that were exposed apriori to various degrees of alkaline degradation. To... more
The objective of the present in vitro study was to determine vascular endothelial and smooth muscle cell responses to poly(lactic-co-glycolic acid) (PLGA) films that were exposed apriori to various degrees of alkaline degradation. To model the alkaline environment of blood in arteries, PLGA films were separately soaked in select concentrations (from 0.1 – 10 N) of NaOH for various periods of time (from 10 minutes to 1 hour). Vascular endothelial and smooth muscle cells were then separately allowed to adhere and/or proliferate on the different PLGA degraded surfaces. Results provided the first evidence that smooth muscle adhesion and proliferation increased with larger amounts of alkaline PLGA degradation. In contrast, endothelial cell adhesion and proliferation decreased with increasing amounts of alkaline PLGA degradation. In this manner, the present in vitro study suggests a possible mechanism for insufficient endothelialization on PLGA vascular implants in vivo.
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People receiving treatment for multidrug-resistant tuberculosis (MDR-TB) have high rates of depression. Psychosocial support in general, and treatments for depression in particular, form an important but neglected area of patient-centred... more
People receiving treatment for multidrug-resistant tuberculosis (MDR-TB) have high rates of depression. Psychosocial support in general, and treatments for depression in particular, form an important but neglected area of patient-centred care, and a key pillar in the global End TB strategy. We assessed the feasibility and acceptability of a psychosocial support package for people receiving treatment for MDR-TB in Nepal. This feasibility study used a mixed quantitative and qualitative approach. We implemented the intervention package in two National Tuberculosis Programme (NTP) MDR-TB treatment centres and 8 sub-centres. We screened patients monthly for depression and anxiety (cut-off ≥24 and ≥17 respectively on the Hopkins Symptom Checklist) and also for low social support (cut-off ≤3 on the Multidimensional Scale of Perceived Social Support). Those who screened positive on either screening tool received the Healthy Activity Program (HAP), which uses brief counselling based on behav...
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Tuberculosis (TB) is a major public health concern for Nepal like many other developing countries around the world. Economic barrier is one of the major problems in poor and marginalized population. Poor people mostly remain unaware of... more
Tuberculosis (TB) is a major public health concern for Nepal like many other developing countries around the world. Economic barrier is one of the major problems in poor and marginalized population. Poor people mostly remain unaware of the treatment facilities and some find it difficult in seeking T.B treatment as they don’t trust the program and most of them don’t possess enough knowledge about the disease itself. Population residing in the remote areas of the countries can’t access the treatment facilities due to far distance of health facilities from there residence due to lack of roads and lack of transport. Thus difficult geography primarily in rural areas in the country acts as a barrier to access the health facility. TB infection faces add-on challenge with the advent of co-infection and possibility of increase in drug resistant TB. This is why detecting TB in its early stage would pose a number of advantages to the patient that would in turn help for early treatment. However...
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... ENHANCED FUNCTIONS OF CELLS ON POLYMERS WITH NANOSTRUCTURED SURFACES D. C. Miller, A. Thapa, KM Haberstroh, and TJ Webster Department of ... Results f?om the present study also provided the first evidence of enhanced proliferation of... more
... ENHANCED FUNCTIONS OF CELLS ON POLYMERS WITH NANOSTRUCTURED SURFACES D. C. Miller, A. Thapa, KM Haberstroh, and TJ Webster Department of ... Results f?om the present study also provided the first evidence of enhanced proliferation of aortic smooth ...
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ABSTRACTBiomaterials that successfully integrate into surrounding tissue should match not only the tissue's mechanical properties, but also the dimensions of the associated nano-structured extra-cellular matrix (ECM) components. The... more
ABSTRACTBiomaterials that successfully integrate into surrounding tissue should match not only the tissue's mechanical properties, but also the dimensions of the associated nano-structured extra-cellular matrix (ECM) components. The goal of this research was to use these ideals to develop a synthetic, nano-structured, polymeric biomaterial that has cytocompatible and mechanical behaviors similar to that of natural vascular tissue. In a novel manner, poly-lactic acid/polyglycolic acid (PLGA) (50/50 wt.% mix) and polyurethane were separately synthesized to possess a range of fiber dimensions in the micron and nanometer regime. Preliminary results indicated that decreasing fiber diameter on both PLGA and PU enhanced arterial smooth muscle cell adhesion; specifically, arterial smooth muscle cell adhesion increased 23% when PLGA fiber dimensions decreased from 500 to 50 nm and increased 76% on nano-structured, compared to conventional structured, polyurethane. However, nano-structure...
ABSTRACT A reduction of material consumption in thin-film photovoltaic devices can make solar energy economically more viable. However, since thin films essentially absorb less light, there is an imminent need for existing technology to... more
ABSTRACT A reduction of material consumption in thin-film photovoltaic devices can make solar energy economically more viable. However, since thin films essentially absorb less light, there is an imminent need for existing technology to improve light harvesting. We present an effective approach of better light absorption, enhanced photocurrent generation and therefore higher quantum efficiency of poly (3-hexylthiophene): 1-(3-methoxycarbonyl) propyl-1-phenyl-[6, 6]-methanofullerene (P3HT:PCBM) bulk heterojunction photovoltaic/photodetector devices. We have integrated a thin semi-continuous gold film (SCGF) (~20nm) sputtered at percolation threshold between the active P3HT:PCBM layer and the indium-tin-oxide (ITO) electrode. At critical metal concentrations, i.e. percolation threshold, the light reaching the SCGF undergoes a broadband trapping with characteristic time of 200 fs, through complex interactions with fractal gold clusters. This thin SCGF together with the ITO serves as an anode. The interface between SCGF and the polymer represents the metaldielectric composite (MDC) that supports broad-band surface plasmon resonances that store electromagnetic radiation at the nanoscale and acts as an effective bulk type of concentrator without the need of increasing the photovoltaic device physical collection area. Here we report a six-fold enhancement in the integral quantum efficiency over the solar spectrum for device employing plasmon-active gold layer. Such enhancement is an important contribution for the future design of more efficient photodetecting/photovoltaic devices. The experimental results are supported by the theoretical modeling of metal-dielectric composites by block elimination method in 3D. The AC and DC responses of MDC, local field distribution, broad optical response and photon trapping in the percolating MDC were numerically calculated.
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ABSTRACTConventionally, studies investigating the design of synthetic bladder wall substitutes have involved polymers with micro-dimensional structures. Since the body is made up of nano-structured components (e.g., extracellular matrix... more
ABSTRACTConventionally, studies investigating the design of synthetic bladder wall substitutes have involved polymers with micro-dimensional structures. Since the body is made up of nano-structured components (e.g., extracellular matrix proteins), our focus has been in the use of nano-structured polymers in order to design a three-dimensional synthetic bladder construct that mimics bladder tissue in vivo. In order to complete this task, we fabricated novel, nano-structured, biodegradable materials to serve as substrates for bladder tissue constructs and tested the cytocompatibility properties of these biomaterials in vitro. The results from our in vitro work to date have provided the first evidence that cellular responses (such as adhesion and proliferation) of bladder smooth muscle cells are enhanced as poly (lactic-co-glycolic acid) (PLGA) surface feature dimensions are reduced into the nanometer range.
Introduction: Neonatal period is the most susceptible period of life due to different causes, which in most cases are preventable. Every year millions of neonates are born and a large proportion of them are admitted to the neonatal... more
Introduction: Neonatal period is the most susceptible period of life due to different causes, which in most cases are preventable. Every year millions of neonates are born and a large proportion of them are admitted to the neonatal intensive care unit (NICU) for various indications. One of the Millennium Development Goals is to reduce under five mortality by two thirds by 2015. Therefore, this study was conducted to identify the clinical profile, pattern of diseases and common causes of mortality and morbidity in neonates admitted to NICU. Materials and Methods: A retrospective study was conducted at level III Neonatal NICU of a tertiary -care teaching hospital from January, 2012 to December, 2012. Results: Total of 361 neonates were admitted in NICU. Eighty six neonates (23.8%) were admitted due to prematurity and 73 (20.2%) with birth asphyxia. Among birth asphyxia, 40(54.8%)were in HIE III, 27.4% and 17.8% in HIE II and HIE I, respectively. One hundred eighteen (32.6%) cases were...
We report here an unusual case of post-traumatic isolated sixth nerve palsy occurring while nursing the patient in trendelenburg position. This is the first case to be reported in the available literature of posture induced delayed onset... more
We report here an unusual case of post-traumatic isolated sixth nerve palsy occurring while nursing the patient in trendelenburg position. This is the first case to be reported in the available literature of posture induced delayed onset isolated post-traumatic sixth nerve palsy and highlights importance of avoiding head down position while nursing patients with head injury.DOI: http://dx.doi.org/10.3126/jkmc.v3i1.10921Journal of Kathmandu Medical College Vol. 3, No. 1, Issue 7, Jan.-Mar., 2014, Page: 32-33
Osteoblast (bone-forming cell) and chondrocyte (cartilage-synthesizing cell) adhesion on novel nanostructured polylactic/glycolic acid (PLGA) and titania composites were investigated in the present in vitro study. Nanostructured polymers... more
Osteoblast (bone-forming cell) and chondrocyte (cartilage-synthesizing cell) adhesion on novel nanostructured polylactic/glycolic acid (PLGA) and titania composites were investigated in the present in vitro study. Nanostructured polymers were created by chemically treating micron-structured PLGA with select concentrations of NaOH for various periods of time. Dimensions of ceramics were controlled by utilizing either micron or nanometer grain size titania. Compared with surfaces with conventional or micron surface roughness dimensions, results provided the first evidence of increased osteoblast and chondrocyte adhesion on 100 wt% PLGA films with nanometer polymer surface roughness dimensions. Results also confirmed other literature reports of enhanced osteoblast adhesion on 100 wt% nanometer compared with conventional grain size titania compacts; however, the present study provided the first evidence that decreasing titania grain size into the nanometer range did not influence chondrocyte adhesion. Finally, osteoblast and chondrocyte adhesion increased on 70/30 wt% PLGA/titania composites formulated to possess nanosurface rather than conventional surface feature dimensions. The present study, thus, provided evidence that these nanostructured PLGA/titania composites may possess the ability to simulate surface and/or chemical properties of bone and cartilage, respectively, to allow for exciting alternatives in the design of prostheses with greater efficacy.
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Polymers currently utilized for tissue engineering applications do not possess surfaces with nanostructured features. However, the tissue that the polymers will replace is composed of proteins that have nanometer dimensions. Undoubtedly,... more
Polymers currently utilized for tissue engineering applications do not possess surfaces with nanostructured features. However, the tissue that the polymers will replace is composed of proteins that have nanometer dimensions. Undoubtedly, in situ, cells are accustomed to interacting with surface roughness values in the nanometer regime due to the presence of such proteins in natural tissue. Therefore, the objective of this paper was to design, synthesize and evaluate (using in vitro cellular models) poly-lactic-co-glycolic acid (PLGA) with nanostructured surface features to serve as the next generation of more efficient tissue engineered materials. For this purpose, nanostructured PLGA was created by treating conventional PLGA with various concentrations of NaOH for select periods of time. To eliminate surface chemistry changes created though the etching process, PLGA was cast from silastic molds of NaOH-treated nanostructured PLGA. Results provided the first evidence of increased numbers of vascular cells (specifically, endothelial and aortic smooth muscle cells) and bladder smooth muscle cells on nanostructured compared with conventional PLGA substrates. For this reason, the present results suggest, for the first time, that PLGA should incorporate a high degree of nanostructured surface roughness to enhance tissue regeneration for vascular and bladder applications.