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Effects of Bumblebee Domestication on Pollen Collection.
No full textSummer Scholars 2018 final poster presentationResearch with Dr. Elizabeth Crone and her laboratory on the possible link between domestication of Bombus impatiens bumblebees and pollen collection behavior. Submitted in partial fulfillment of the grant requirement of the Tufts Summer Scholars Program
Augmented Reality for Collaborative Service Robots.
No full textCreating an Augmented Reality interface between humans and robots Submitted in partial fulfillment of the grant requirement of the Tufts Summer Scholars Program
Measuring the self-correction of brain morphology in pre-metamorphic Xenopus laevis tadpoles by examining markers of brain tissue differentiation and cerebrospinal fluid flow.
No full textThe McLaughlin lab is working to elucidate the underlying mechanisms that direct the self-correction of malformed tissues in the heads of Xenopus laevis tadpoles, with the ultimate goal of supporting the discovery of novel treatments for correcting human craniofacial birth defects. To help this objective, my project focused on determining whether brain tissue in pre- metamorphic tadpoles with craniofacial defects is properly differentiated prior to and after the life stages where malformed craniofacial tissues are known to correct. The second part of my project was to examine the cerebrospinal fluid flow in the brains to determine whether or not there was a blockage of flow in the malformed brains, and whether this is corrected over time as well. Submitted in partial fulfillment of the grant requirement of the Tufts Summer Scholars Program
Effect of thermal processing on phytic acid, inorganic phosphorous and proximate composition of pigeon pea.
No full textThis presentation was from 6th Annual scientific Symposium in Nepal
ENERGY EXPENDITURE, TIME USE, AND FOOD INTAKES IN AGRICULTURAL AND RURAL LIVELIHOODS Descriptive findings from rural Nepal.
No full textThis presentation was from 6th Annual scientific Symposium in Nepal
A qualitative study to understand sustained activities of Action Against Malnutrition through Agriculture (AAMA) project - an integrated rural nutrition intervention in Nepal.
No full textThis presentation was from 6th Annual scientific Symposium in Nepal
The Role of Sulfur Amino Acids in Risk of Kwashiorkor
No full textAbstract: Kwashiorkor is a form of severe acute malnutrition identified more than 80 years ago as a syndrome and still affects hundreds of thousands of children each year, yet its etiology remains unknown. A better understanding of its etiology is necessary to develop effective preventive strategies. Although kwashiorkor is only found in regions where protein intake and sanitation are poor, study findings comparing the dietary protein intake of children with and without kwashiorkor have been conflicting. Protein quality has not been explored and the large array of signs characterizing kwashiorkor can plausibly be explained by a deficiency of sulfur amino acids (SAAs). Children with kwashiorkor have low circulating sulfur amino acids (methionine and cysteine) and their metabolites, and their metabolism of SAAs is altered. The aim of this research is to provide evidence upon which to design preventive interventions, hypothesizing that children in higher-prevalence populations will have lower intakes of SAAs, and that low intake of SAAs will be a stronger predictor of the risk of kwashiorkor than other factors. Additionally, due to its low nutrient content and potentially high cyanide content, cassava intake was hypothesized to be a stronger predictor of risk than food security. An anthropometric survey of all children in one Health Area of eastern Democratic Republic of the Congo located all cases of kwashiorkor among children 12 to 59 months old to aid in the selection of two populations with very different prevalence. A commercial laboratory was used to provide amino acid profiles on market samples of key staples and sources of proteins. Household samples of cassava flour and cooked cassava leaves were tested for cyanogens. Interviews with caregivers of children 36 to 59 months old recorded multiple factors of the household and the child and a 24-hour quantitative recall of the child's diet. Among the many signs characterizing kwashiorkor, only bipedal pitting edema is used for admission to treatment, though light-colored brittle hair and facial edema have been reported to appear before edema in the feet, therefore all visible signs were recorded. One urine sample was taken to compare urinary sulfate and another for thiocyanate. Analysis included GIS mapping, direct statistical comparisons of diets, and path analysis modeling of the multiple potential causal factors. Together, the findings showed children in a population with a higher prevalence of kwashiorkor had lower intakes of sulfur amino acids, methionine in particular, more children in this population were at risk of inadequate methionine intake than other amino acids, and methionine was the limiting amino acid in both populations. Median intake of both methionine and cysteine was above the WHO requirement, but true adequacy of a nutrient must take into consideration factors that raise the requirement. Children in the HPP were more stunted, were ill more often, and their families were more food insecure than those in a lower-prevalence population. SAA intake, followed by illness, was the strongest predictor of a family history of kwashiorkor. A family history of kwashiorkor, followed by illness, was the strongest predictor of early signs of kwashiorkor. It appears that low SAA intake makes children especially vulnerable to kwashiorkor, but illness is often the event that triggers the onset of the syndrome. Intervention trials to reduce prevalence of kwashiorkor should simultaneously reduce exposure to infection and increase intake of both cysteine and methionine.Thesis (Ph.D.)--Tufts University, 2017.Submitted to the Dept. of Food Policy & Applied Nutrition.Advisor: Daniel Maxwell.Committee: Shibani Ghosh, Anura Kurpad, and Christopher Duggan.Keywords: Nutrition, Public health, and Epidemiology
Optical Interfaces for Solid State Power Conversion and Advanced Molecular Beam Epitaxy
No full textAbstract: This work covers three topics related to the design and fabrication of optoelectric devices used for power generation. The first section describes research on frequency-selective emitters employing a Fabry-Perot design. These emitters are intended for use in the infrared and will tune the photonic output of a thermal power source to match the best operating point of a power conversion device. The second section describes a project to produce an easily manufactured, broad-spectrum absorption surface by fabricating a biomimetic "Moth's Eye" structure. The third section describes the restoration and upgrading of a molecular beam epitaxy tool which will be used to research silicon/germanium based materials and devices.Thesis (Ph.D.)--Tufts University, 2018.Submitted to the Dept. of Electrical Engineering.Advisor: Thomas Vandervelde.Committee: Kevin Grossklaus, Marc Hodes, and Ganesh Balakrishnan.Keywords: Electrical engineering, Optics, and Materials Science
Authoritarian Resurgence: Power, Politics and the Making of Foreign Policy in Russia and China
No full textAbstract: A quarter-century after the fall of the Berlin Wall and the collapse of the Soviet Union, leading authoritarian regimes are reasserting influence in their regions and are progressing from consolidating power within their borders to projecting power beyond them. Nowhere is this trend more evident, or important, than in contemporary Russia and China - the world's two most powerful authoritarian states. Instrumental in this success has been their adaptation to globalization and modern technology - phenomena once thought of as destabilizing for autocrats - by employing advanced tools of monitoring and censorship to maintain control over their domestic populations. Concurrently, Russia and China throughout the twenty-first century represent two cases of great power authoritarian regimes that are developing more assertive foreign policies and military strategies in their respective regions. In practice, Russia continues to destabilize and interfere in Ukraine and the near abroad while China has proven more aggressive over its territorial claims in the East and South China Seas. What is less understood, however, are the linkages between heightened authoritarianism at home and the propensity to pursue revisionist foreign policies. The question remains: what are the connections, if any, between these domestic and foreign policy trends? The primary argument of this research is that there are internal dynamics within Russia and China that are influencing their foreign policy preferences, objectives, and ultimately, behavior. For these authoritarian regimes, the domestic and foreign domains are inextricably linked: internal consolidations of power and assertive foreign policy strategies are needed to achieve stability at home, as well as the legitimacy of great powers in the international system. While political survival is the objective of all regimes, both democratic and authoritarian, domestic stability and regime security are critical elements of authoritarian political orders. Insecurity among regime elites and insiders is felt in markedly different ways than those in democratic systems, as being removed from power might entail not only losing political power but also material wealth and personal freedom. Importantly, this insecurity affects foreign policy in that it makes autocratic political actors wary of external influences that seek to destabilize their internal orders and leads them to take steps that maximize their legitimacy and power - at home and abroad. While empirical evidence shows that authoritarian systems are not inherently more warlike, this research develops more nuanced categories and theories that link Russia and China's domestic conditions to their foreign policies, with the goal of ascertaining the specific facets of authoritarian control that are most detrimental to peace and stability. Specifically, this research assesses the influence on foreign policy of domestic variables including the emergence of nationalist individuals and groups, their consolidation of control across political institutions and processes, and the existence of powerful challenges to regime legitimacy. This research applies process tracing and congruence methodology to a series of in-depth case studies that cover Russian and Chinese domestic politics and foreign policy between 2000 and 2017. Each case study seeks to illustrates the interaction of factors behind the pursuit of revisionist foreign policy strategies. Ultimately, the aim is to build greater understanding of why, how, and to what extent Russia and China are pushing the boundaries of their regional orders in efforts to build "spheres of influence," and what these developments mean for the shaping and conduct of U.S. foreign policy. Russia and China's trajectories - internally and externally - have the power to either enforce or destabilize the liberal international order. Conflict and war are not inevitable, but we cannot avoid what we do not understand.Thesis (Ph.D.)--Tufts University, 2018.Submitted to the Dept. of Diplomacy, History, and Politics.Advisor: Richard Shultz.Committee: Robert Pfaltzgraff, and Nicholas Burns.Keyword: International relations