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The family of transition-metal dipnictides has been of theoretical and experimental interest because this family hosts topological states and extremely large magnetoresistance (MR). Recently,TaAs2, a member of this family, has been predicted to support a topological crystalline insulating state. Here, by using high-resolution angle-resolved photoemission spectroscopy (ARPES), we reveal both closed and open pockets in the metallic Fermi surface (FS) and linearly dispersive bands on the (2‾01) surface, along with the presence of extreme MR observed from magneto-transport measurements. A comparison of the ARPES results with first-principles computations shows that the linearly dispersive bands on the measured surface ofTaAs2are trivial bulk bands. The absence of symmetry-protected surface state on the (2‾01) surface indicates its topologically dark nature. The presence of open FS features suggests that the open-orbit fermiology could contribute to the extremely large MR ofTaAs2.

The EGS Collab project performed well-monitored rock stimulation and flow tests at the 10-m scale in an underground research laboratory to inform challenges in implementing enhanced geothermal system (EGS) technology. This project, supported by the US Department of Energy, gathered data and observations from the field tests and compared these to simulation results to understand processes and to build confidence in numerical modeling of the processes. The project consisted of 3 Experiments, each comprising test and testbed design, many individual tests, numerical simulation, and analysis. The Experiments were performed in two deep underground testbeds at the Sanford Underground Research Facility (SURF) in Lead, South Dakota. Field experiments are now complete, significant data sets have been collected and analyzed, and some analysis continues. Experiments using underground test facilities have many advantages in that they allow:•Three-dimensional characterization of the stimulated volume by complementary geophysical methods surrounding the experiment•Using techniques that are currently not applicable under geothermal condition to provide processes insight •Comprehensive tracer testing and detailed characterization of complex fluid movements•Understanding the geometry of the stimulated network at the meso-scale and its implications for effective fracture surface area, rock block size, and heat exchange.Underground testing has its own set of complications, however, which affect the ability to perform tests as desired and affect the experiment results. Included here are the inability to flow at desired injection rates due to stress gradients caused by drift cooling, and the need to strongly limit induced seismicity because the distance to people and equipment.Experiment 1 examined hydraulic fracturing at a depth of 1.5 km in a well-characterized phyllite. Eight subhorizontal boreholes were used in this Experiment. Geophysical monitoring instrumentation was deployed in six boreholes to monitor stimulation events and flow tests. The other two boreholes were used to perform and carefully measure water injection and production. More than a dozen stimulations and nearly one year of flow tests in the testbed were performed. Detailed observations of processes occurring during stimulation and dynamic flow tests were collected and analyzed. Flow tests using ambient-temperature and chilled water were performed with intermittent tracer tests to examine system behavior. We achieved adaptive control of the tests using close monitoring of rapidly disseminated data and near-real-time simulation. Numerical simulation was critical in answering key experimental design questions, forecasting fracture behavior, and analyzing results. We were successful in performing many simulations in near-real-time in conjunction with the field experiments, with more detailed simulations performed later. Experiment 2 was intended to examine hydraulic shearing of natural fractures at a depth of 1.25 km in amphibolite. The stresses, rock type, and fracture conditions are different than in Experiment 1. The testbed consists of 9 boreholes, in addition to 2 exploratory characterization boreholes. Four boreholes drilled as two fans of 2 monitoring holes contained grouted-in monitoring sensors. The remaining five open boreholes drilled in a five-spot pattern were adaptively used for injection, production, and monitoring. Approximately five fracture set orientations were encountered in the testbed along with a low-stress rhyolite sill at 35 m below the access drift in exploratory well TV4100. The testbed was designed to optimize the potential for shear stimulation while also avoiding the low-stress rhyolite. Experiment 2 focused on stimulating a fracture in the most likely orientation to shear, however shear stimulation did not occur probably due to cementation from natural secondary mineralization. Other fracture sets encountered were also cemented and had orientations less likely to shear.Experiment 3 consisted of several stimulations in the same testbed as Experiment 2 allowing different stimulation approaches including ramped-rate injection, rapid injection, and oscillating-pressure injection. Ultimately these methods created hydraulic fractures, one of which was used for a medium-duration cold water injection test. The major findings of the EGS Collab Project include: 1.Significant shear stimulation did not occur during our stimulation attempts. Shear stimulation may occur but under a limited set of conditions not encountered.2.Our stimulations resulted in hydraulic fractures that required hydraulic propping. Pumping at pressures exceeding the minimum principal stress may not be feasible in an enhanced geothermal system.3.The systems we generated were complex hydraulic fracture/natural fracture systems, and these systems changed over time in response to applied pressures and flowrates and to unknown stimuli.4.The project attempted alternative stimulation methods, which did not provide significant flow improvement. 5.Thermal breakthrough was not achieved as designed, most likely because flow to production boreholes was not adequate. 6.The combination of geophysical tools used provided excellent understanding of many important processes. 7.Microearthquakes (MEQs) didn’t necessarily identify flow paths.8.Engineering tools bounding expected seismicity are needed.This report provides a summary of tests and analyses performed for EGS Collab Experiment 2 (Shear Stimulation in Testbed 2) and Experiment 3 (Alternative Stimulation methods). Much of the EGS Collab work has been published in journals and conference papers, presented in conferences, included in written reports, and submitted in data sets to the Geothermal Data Repository (GDR). The entirety of these written works is included as an appendix to this report, and this report serves as a summary and framework pointing to these published papers, presentations, and reports.

Abstract Background Particulate matter (PM), including the major risk factor for lung cancer (LC), greatly impacts human health. Although numerous studies have highlighted spatiotemporal patterns and PM-LC associations, these studies have not been well-reviewed. Thus, we examined epidemiological studies linked with PM-LC and provided concise, up-to-date data. Methods We used certain keywords to review articles published in PubMed, Web of Science, Scopus, and Google Scholar until 30th June 2024 and identified 1474 research articles. We then filtered the research articles based on our criteria and ultimately dropped down to 30 for this review. Results Out of the thirty reviewed studies on the PM-LC relation, twenty-four focused on PM2.5, four on PM10, and two on both, indicating that approximately 80% of the respondents were inclined toward fine particles and their health impacts. The study revealed that 22 studies used visualization, 12 used exploration, and 15 used modeling methods. A strong positive relationship was reported between LC and PM2.5, ranging from 1.04 to 1.60 (95% CI) for a 10 µg/m3 increase in PM2.5 exposure. However, compared to PM2.5, PM10 was found to have a significantly less positive association. Conclusions Very few studies have used advanced spatiotemporal methods to examine the association between LC and PM. Advanced spatiotemporal analysis techniques should be employed to explore this association in specific geographical locations. Further research should utilize spatiotemporal epidemiological approaches to study the link between PM and lung cancer.

Abstract Objective The purpose of the present study was to explore the effect of plateau duration in eliciting masseter vestibular evoked myogenic potentials (mVEMPs) in healthy individuals with hearing sensitivity ≤ 15dBHL. Method A within-subjects design was utilized in the study. Therefore, ipsilateral tone burst evoked mVEMPs were obtained from 30 healthy individuals using the zygomatic montage at 500 Hz tone bursts. Self-monitoring biofeedback was given during the procedure to confirm the tension of the masseter muscle. mVEMPs were recorded across three different plateau duration from 0 to 2 ms with rise/fall time of 2 ms at 95dBnHL. Hence the median and interquartile range were calculated for descriptive analysis of the data followed by non-parametric inferential statistics. Results Tone burst evoked mVEMPs were found to be 100% present across all three plateau durations for both ears at 95 dBnHL. P11 and N21 latencies increased with longer plateau durations in both ears. There were no significant differences in P11-N21 peak-to-peak amplitude or interaural amplitude ratio (IAAR) observed across different plateau durations. IAAR was lowest for a 2 ms plateau duration in the 2–2-2 cycle. No significant variations were found across the three plateau durations. Conclusion Significant differences in P11 and N21 latencies were observed across the three stimulus cycles, while no significant differences were found for P11N21 amplitude and IAAR. Yet, there was found to have the highest amplitude and lowest IAAR for 2–2-2 cycle than 2–0-2 and 2–1-2, suggesting it to be the optimal stimulus among the three of them.

This paper aims to identify the factors affecting employee retention in Nepalese financial institutions, especially commercial banks. Through a questionnaire, the primary data were collected from 400 respondents. The study is based on a dichotomous and 5-point Likert scale questionnaire. The collected data were analyzed using SPSS and structural equation modeling (SEM). SEM smart PLS-4 is used to examine the association between the dependent and independent variables. The results indicate that company image/goodwill, employee benefits, job satisfaction, organizational performance, recruitment and selection, and work environment and culture have a relatively significant relationship with employee retention. Among them, organizational performance was found to be highly significant among all other variables. However, labor unions, leadership support, performance appraisal, training and development, and work-life balance did not have an association with employee retention. The study helps HR managers to formulate appropriate policies and guidelines to retain employees in Nepalese commercial banks. Likewise, it provides a valuable empirical contribution by analyzing which factors affect employee retention in commercial banks in Nepal using a direct SEM model. It also shows which factors play a major role in employee retention.

Abstract Background Fusarium head blight (FHB), caused by Fusarium graminearum, is a major disease of wheat in North America. FHB infection causes fusarium damaged kernels (FDKs), accumulation of deoxynivalenol (DON) in the grain, and a reduction in quality and grain yield. Inheritance of FHB resistance is complex and involves multiple genes. The objective of this research was to identify QTL associated with native FHB and DON resistance in a ‘D8006W’/’Superior’, soft white winter wheat population. Results Phenotyping was conducted in replicated FHB field disease nurseries across multiple environments and included assessments of morphological and FHB related traits. Parental lines had moderate FHB resistance, however, the population showed transgressive segregation. A 1913.2 cM linkage map for the population was developed with SNP markers from the wheat 90 K Infinium iSelect SNP array. QTL analysis detected major FHB resistance QTL on chromosomes 2D, 4B, 5A, and 7A across multiple environments, with resistance from both parents. Trait specific unique QTL were detected on chromosomes 1A (visual traits), 5D (FDK), 6B (FDK and DON), and 7D (DON). The plant height and days to anthesis QTL on chromosome 2D coincided with Ppd-D1 and were linked with FHB traits. The plant height QTL on chromosome 4B was also linked with FHB traits; however, the Rht-B1 locus did not segregate in the population. Conclusions This study identified several QTL, including on chromosome 2D linked with Ppd-D1, for FHB resistance in a native winter wheat germplasm.

Raba Thapa,1 Sanduk Ruit,2 Manish Prasad Poudel,3 Pratibha Neupane,3 Pradeep Banjara,3 Sushma Duwal,4 Elena Gurung,4 Geoffrey Tabin5 1Department of Vitreo-Retina and Research, Tilganga Institute of Ophthalmology, Kathmandu, Nepal; 2Department of Cataract and Cornea, Tilganga Institute of Ophthalmology, Kathmandu, Nepal; 3Department of Research, Tilganga Institute of Ophthalmology, Kathmandu, Nepal; 4Department of Vitreo-Retina, Tilganga Institute of Ophthalmology, Kathmandu, Nepal; 5Department of Cornea, Byers Eye Institute, Stanford University, Palo Alto, CA, USACorrespondence: Raba Thapa, Department of vitreo-retina and Research, Tilganga Institute of Ophthalmology, Kathmandu, Nepal, Email rabathapa@live.comBackground: Retinal diseases are common at high altitudes due to a cascade of changes caused by hypoxia. The aim of this study is to assess the population prevalence, pattern and associated factors of retinal disorders at high altitude in Nepal.Methodology: A cross-sectional study was conducted at three selected high-altitude districts (over 2500 meters) of Nepal. Subjects were at least 40 years old, and the target sample size was 309. A detailed history was taken. Visual acuity, blood sugar, blood pressure, and oxygen saturation were measured. Anterior and posterior ocular evaluations were conducted by retina specialists using slit lamp and indirect ophthalmoscopy.Results: A total of 338 participants were recruited, with nearly equal numbers from the three districts with mean age of 57.0 (S.D 11.1) years. Two-thirds (63.9%) were females; 38.2% were illiterate, and 46.7% were farmers. Average blood oxygen saturation was 87.2% (S.D 4.1%). Systemic hypertension and diabetes mellitus were found in 58% and 11%, respectively. Retinal diseases were found in 176 (52.5%), with bilateral involvement in 157 (46.9%). The major retinal diseases were hypertensive retinopathy (32.2%), high-altitude retinopathy (10.4%), age-related macular degeneration (AMD) (8.1%), branch vein occlusion (BRVO) (2.1%), and diabetic retinopathy (DR) (1.8%). The multivariate analysis showed significant association of retinal diseases with age and hypertension. Best corrected visual acuity better than 6/18 was present in 96.7%.Conclusion: Over half of the study participants had retinal diseases, with hypertensive retinopathy, AMD, and high-altitude retinopathy as the most common retinal problems. A significant association of retinal diseases was found with ageing, and hypertension. Access to eye care services and control of systemic hypertension along with patient education should be emphasized among people living at high-altitude.Keywords: prevalence, pattern, risk factors, high-altitude retinopathy, Nepal

This study explored the academic activities of academicians during the COVID-19 pandemic in Nepal. An online questionnaire was used to collect quantitative data from 361 academicians about changes in academic and extracurricular activities. The findings showed that the majority of participants (69% and 72%) agreed that both academic and extracurricular activities, respectively, were adversely affected by the lockdown during the pandemic. The results also showed that the study hours, sleeping hours, and social networking increased while concentration on academic activities decreased during the lockdown due to the COVID-19 pandemic.

Background Gaur (Bos gaurus) is listed as a vulnerable species in the IUCN Red List of threatened species due to the rapid population decline caused by human pressures in their habitats. To develop successful conservation plans, it is essential to understand the relationship between Gaur and their habitats. This study aimed to investigate the factors influencing Gaur habitat use and identify and rank conservation threats in Chitwan National Park, Nepal. Methods Using line transect surveys, we recorded Gaur’s presence via direct sightings and indirect signs (dung, footprints, horns) over an area of 176 km2 in July and August 2022. We used binary logistic regression models to determine the collected ecological and anthropogenic factors influencing the occurrence of Gaur and the relative whole-site threat ranking method to rank conservation threats. Results The results revealed that the probability of Gaur occurrence increases with moderate to high canopy cover, riverine and Shorea robusta dominated forests, and nearest distance to road/path/firelines, while decreasing with the presence of predators. Uncontrolled fire, invasive species, human disturbances, and climate change were ranked as the most prevailing threats to Gaur in our study area. Conservation managers should implement effective habitat management interventions, such as construction of waterhole, firelines maintenance, grassland management, and control of invasive species in the potential habitats, to safeguard and maintain the sustainability of Gaur populations and associated herbivores. Future studies should consider larger geographical settings and multiple seasons, and habitat suitability assessments should be conducted to determine current and future suitable habitat refugia for Gaur and other threatened wildlife species at the landscape level.

Activated carbon (AC)-based materials have shown promising performance in carbon capture, offering low cost and sustainable sourcing from abundant natural resources. Despite ACs growing as a new class of materials, theoretical guidelines for evaluating their viability in carbon capture are a crucial research gap. We address this gap by developing a hierarchical guideline, based on fundamental gas-solid interaction strength, that underpins the success and scalability of AC-based materials. The most critical performance indicator is the CO2 adsorption energy, where an optimal range (-0.41 eV) ensures efficiency between adsorption and desorption. Additionally, we consider thermal stability and defect sensitivity to ensure consistent performance under varying conditions. Further, selectivity and capacity play significant roles due to external variables such as partial pressure of CO2 and other ambient air gases (N2, H2O, O2), bridging the gap between theory and reality. We provide actionable examples by narrowing our options to methylamine- and pyridine-grafted graphene.

Fracture injection/shut-in tests are commonly used to measure the state of stress in the subsurface. Injection creates a hydraulic fracture (or in some cases, opens a preexisting fracture), and then the pressure after shut-in is monitored to identify fracture closure. Different interpretation procedures have been proposed for estimating closure, and the procedures sometimes yield significantly different results. In this study, direct, in-situ strain measurements are used to observe fracture reopening and closure. The tests were performed as part of the EGS Collab project, a mesoscale project performed at 1.25 and 1.5 km depth at the Sanford Underground Research Facility. The tests were instrumented with the SIMFIP tool, a double-packer probe with a high-resolution three-dimensional borehole displacement sensor. The measurements provide a direct observation of the fracture closure signature, enabling a high-fidelity estimate of the fracture closure stress (ie, the normal stress on the fracture). In two of the four tests, injection created an opening mode fracture, and so the closure stress can be interpreted as the minimum principal stress. In the other two tests, injection probably opened preexisting natural fractures, and so the closure stress can be interpreted as the normal stress on the fractures. The strain measurements are compared against different proposed methods for estimating closure stress from pressure transients. The shut-in transients are analyzed with two techniques that are widely used in the field of petroleum engineering – the ‘tangent’ method and the ‘compliance’ method. In three of the four tests, the tangent method significantly underestimates the closure stress. The compliance method is reasonably accurate in all four tests. Closure stress is also interpreted using two other commonly-used methods – ‘first deviation from linearity’ and the method of (Hayashi and Haimson, 1991). In comparison with the SIMFIP data, these methods tend to overestimate the closure stress, evidently because they identify closure from early-time transient effects, such as near-wellbore tortuosity. In two of the tests, microseismic imaging provides an independent estimate of the size of the fracture created by injection. When combined with a simple mass balance calculation, the SIMFIP stress measurements yield predictions of fracture size that are reasonably consistent with the estimates from microseismic. The calculations imply an apparent fracture toughness 2-3x higher than typical laboratory-derived values.

ABSTRACTUnlike vertebrates, the number of toothed taxa in invertebrates is very few, with leeches being the only tooth-bearing organisms in the phylum Annelida. Copious studies have been conducted regarding vertebrate teeth; however, studies regarding the structure and function of invertebrate teeth are limited. In this study, the tooth structure of leeches, specifically Hirudo nipponia and Haemadipsa rjukjuana, was revealed, which showed sharp and pointed teeth along the apex of three jaws. Understanding conserved signaling regulations among analogous organs is crucial for uncovering the underlying mechanisms during organogenesis. Therefore, to shed light on the evolutionary perspective of odontogenesis to some extent, we conducted de novo transcriptome analyses using embryonic mouse tooth germs, Hirudo teeth, and Helobdella proboscises to identify conserved signaling molecules involved in tooth development. The selection criteria were particularly based on the presence of tooth-related genes in mice, Hirudo teeth, and Helobdella proboscis, wherein 4113 genes were commonly expressed in all three specimens. Furthermore, the chemical nature of leech teeth was also examined via TEM-EDS to compare the chemical composition with vertebrate teeth. The examination of tissue-specific genetic information and chemical nature between leeches and mice revealed chemical similarities between leech and mice teeth, as well as conserved signaling molecules involved in tooth formation, including Ptpro, Prickle2, and Wnt16. Based on our findings, we propose that leech teeth express signaling molecules conserved in mice and these conserved tooth-specific signaling for dental hard tissue formation in mice would corresponds to the structural formation of the toothed jaw in leeches.

Multidetector computed tomography is considered a reliable, non-invasive modality for diagnosing myocardial bridging. The prevalence of myocardial bridges varies greatly based on the technique used to identify the anomaly. We aimed to evaluate the frequency and morphological features of myocardial bridging in patients who underwent ECG-gated 640 slice Multidetector computed tomography coronary angiography at Shahid Gangalal National Heart Centre.