Essays on the Empirical Study of Migration, Intrahousehold Trade-offs, and Infrastructure Investments

Education and infrastructure are two important development strategies in low-income countries. They foster economic growth by improving labor productivity and facilitating market integration. Evaluating them poses a considerable challenge because schooling choices and infrastructure constructions are influenced by unobserved characteristics that bias OLS estimates. This dissertation uses appropriate natural experiment and instrumental variable strategies to study the effect of skilled emigration prospects on human capital investment, identify intersibling spillovers in education, and evaluate the impact of proximity to road on farm profits. Chapter 1 focuses on a natural experiment that involves the recruitment of Nepali men of Gurkha ethnicity into the British Army to identify whether improved prospects for skilled emigration may stimulate human capital investment at home. While the recruitment originated during the British colonial rule in South Asia, a change in the education requirement for Nepali recruits in 1993 resulted in an exogenous, differential increase in their skilled versus unskilled emigration prospects. I use individual-level information on ethnicity, gender, and age to estimate positive effects on school attainment of Gurkha men. I extend this analysis in chapter 2 to study its impact on education of Gurkha women and estimate the net trade-offs between siblings’ human capital investments. While I find that eligible men responded to the rule change by raising their schooling by over one year, a 30 % increase over their average, part of the improvements in their education came at the expense of their female counterparts living in the same household, whose education decreased by 0.11 years. In chapter 3, I estimate the benefits of having easier access to road on farm profits. I overcome endogenous selection in road placement by constructing an instrument based on a geographic feature. Because mountains in Nepal stretch in a north-south direction, the cheaper cost of constructing a north-south road relative to an east-west road to connect the district headquarters led to greater access for villages in north-south hinterlands relative to those in east-west hinterlands. I find that farmlands appreciate in value by 0.25 percent when the travel time to road decreases by 1 percent.PHDEconomicsUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/96142/1/slesh_1.pd

Wheel-Rail Interface Condition Estimation (W-RICE)

The surface roughness between the wheel and rail has a huge influence on rolling noise level. The presence of the third body such as frost or grease at wheel-rail interface contributes towards change in adhesion coefficient resulting in the generation of noise at various levels. Therefore, it is possible to estimate adhesion conditions between the wheel and rail from the analysis of noise patterns originating from wheel-rail interaction. In this study, a new approach to estimate adhesion condition is proposed which takes rolling noise as input.Comment: 8 pages, 3 figures, JRC2020 conferenc

Prevalence of Gastrointestinal Parasites in Lactating Kiko Does and their Kids in Woodlands with Supplements

Gastrointestinal (GI) parasites pose a major health concern in goats raised in pastures. The study objective was to evaluate GI parasites’ prevalence in lactating Kiko does and kids stocked in woodlands with supplemental grazing or feedstuffs. Seventeen lactating Kiko does, and their thirty-three kids were divided into two groups. Group 1 was supplemented with grazing in silvopastures and Group 2 with ad libitum hay and corn (0.5% of metabolic weight) along with stocking in woodland plots rotationally. Fecal samples were analyzed for type and quantity of GI parasites from animals having FAMACHA score 3 and higher. Group-1 does showed a better FAMACHA score and lower parasite infestation vs. Group-2 does. However, kids in Group 1 had a higher infestation of helminth parasites, but lower coccidia counts. This study indicated that grazing quality pastures is a better option for supplementing lactating does stocked in woodlands vs. feedstuffs

Cross-modal Contrastive Learning with Asymmetric Co-attention Network for Video Moment Retrieval

Video moment retrieval is a challenging task requiring fine-grained interactions between video and text modalities. Recent work in image-text pretraining has demonstrated that most existing pretrained models suffer from information asymmetry due to the difference in length between visual and textual sequences. We question whether the same problem also exists in the video-text domain with an auxiliary need to preserve both spatial and temporal information. Thus, we evaluate a recently proposed solution involving the addition of an asymmetric co-attention network for video grounding tasks. Additionally, we incorporate momentum contrastive loss for robust, discriminative representation learning in both modalities. We note that the integration of these supplementary modules yields better performance compared to state-of-the-art models on the TACoS dataset and comparable results on ActivityNet Captions, all while utilizing significantly fewer parameters with respect to baseline

Impact study of temperature on the time series electricity demand of urban Nepal for short-term load forecasting

Short-term electricity demand forecasting is one of the best ways to understand the changing characteristics of demand that helps to make important decisions regarding load flow analysis, preventing imbalance in generation planning, demand management, and load scheduling, all of which are actions for the reliability and quality of that power system. The variation in electricity demand depends upon various parameters, such as the effect of the temperature, social activities, holidays, the working environment, and so on. The selection of improper forecasting methods and data can lead to huge variations and mislead the power system operators. This paper presents a study of electricity demand and its relation to the previous day’s lags and temperature by examining the case of a consumer distribution center in urban Nepal. The effect of the temperature on load, load variation on weekends and weekdays, and the effect of load lags on the load demand are thoroughly discussed. Based on the analysis conducted on the data, short-term load forecasting is conducted for weekdays and weekends by using the previous day’s demand and temperature data for the whole year. Using the conventional time series model as a benchmark, an ANN model is developed to track the effect of the temperature and similar day patterns. The results show that the time series models with feedforward neural networks (FF-ANNs), in terms of the mean absolute percentage error (MAPE), performed better by 0.34% on a weekday and by 8.04% on a weekend

PolyGA targets the ER stress-adaptive response by impairing GRP75 function at the MAM in C9ORF72-ALS/FTD.

ER stress signaling is linked to the pathophysiological and clinical disease manifestations in amyotrophic lateral sclerosis (ALS). Here, we have investigated ER stress-induced adaptive mechanisms in C9ORF72-ALS/FTD, focusing on uncovering early endogenous neuroprotective mechanisms and the crosstalk between pathological and adaptive responses in disease onset and progression. We provide evidence for the early onset of ER stress-mediated adaptive response in C9ORF72 patient-derived motoneurons (MNs), reflected by the elevated increase in GRP75 expression. These transiently increased GRP75 levels enhance ER-mitochondrial association, boosting mitochondrial function and sustaining cellular bioenergetics during the initial stage of disease, thereby counteracting early mitochondrial deficits. In C9orf72 rodent neurons, an abrupt reduction in GRP75 expression coincided with the onset of UPR, mitochondrial dysfunction and the emergence of PolyGA aggregates, which co-localize with GRP75. Similarly, the overexpression of PolyGA in WT cortical neurons or C9ORF72 patient-derived MNs led to the sequestration of GRP75 within PolyGA inclusions, resulting in mitochondrial calcium (Ca2+) uptake impairments. Corroborating these findings, we found that PolyGA aggregate-bearing human post-mortem C9ORF72 hippocampal dentate gyrus neurons not only display reduced expression of GRP75 but also exhibit GRP75 sequestration within inclusions. Sustaining high GRP75 expression in spinal C9orf72 rodent MNs specifically prevented ER stress, normalized mitochondrial function, abrogated PolyGA accumulation in spinal MNs, and ameliorated ALS-associated behavioral phenotype. Taken together, our results are in line with the notion that neurons in C9ORF72-ALS/FTD are particularly susceptible to ER-mitochondrial dysfunction and that GRP75 serves as a critical endogenous neuroprotective factor. This neuroprotective pathway, is eventually targeted by PolyGA, leading to GRP75 sequestration, and its subsequent loss of function at the MAM, compromising mitochondrial function and promoting disease onset