10A - Drugs and the Body University of Warwick and Baruch College, CUNY
It has been found that as little as five minutes of exposure to media images can have a negative impact on self-esteem and body image. This study looked at the effects of exposure to media images on body image in 202 university students to determine whether this effect was mediated by the participation in either team or individual sports. Participants were randomly assigned to either the Experimental Condition, where they were exposed to media images of idealized bodies, or the Control Condition, where they were exposed to neutral images. It was found that participants who were exposed to images of ideal media body types had higher body dissatisfaction. In particular, females were found to have a greater BMI discrepancy due to viewing themselves as larger than they were, and males were found to be the opposite. In addition, sport was found to not mediate the effects of media exposure, with athletes in both individual and team sport reporting the same levels of body dissatisfaction.
Humans react differently to certain drugs due to their genotypes: while some are really sensitive and react to the drug’s effects, others are unaffected by it. Ideally, people would only be prescribed drugs that work for their genotypes. In our experiment, we wanted to know how genetic variation or certain mutations, affect drug sensitivity. Juvenile hormone (JH) plays a special role in insect development. When present with the hormone ecdysone, JH usually induces larval moulting, sloughing its skin to allow growth into a larger larva until it is big enough to undergo metamorphosis. When this happens, the JH hormone production is stopped and only the ecdysone hormone production remains, inducing pupal formation before the emergence of an adult. JH thus inhibits metamorphosis. Fruit flies have larval stages followed by pupa formation to begin metamorphosis into an adult. A JH analogue, methoprene, is used as an insecticide that disrupts metamorphosis preventing adulthood. In this experiment, 93 genotypes were treated with methoprene at the third instar larval stage and scored for dead wandering third instar larvae. We found variability in the number of dead larvae, the most being from the DGRP line genotype 21. We then conducted a Genome-wide Association Study on the percentage of dead larvae to seek a correlation between mutations and methoprene sensitivity; we found about 1000 associations p<.00005. To see if any mutations fell within ecdysone or methoprene target genes, the results were then intersected with known methoprene-tolerant and ecdysone receptor DNA binding sites from ChIP-seq analysis using the online program Galaxy. Two mutations overlapped with the edysone receptor DNA binding sites, around the region between the gene ecdysone inducible protein 74EF at locations 17551305 and 17551309 of chromosome 3L. There are also mutations in genes wrts, scrib, Dgl1 and Fj, which play part of the conserved HIPPO pathway. The HIPPO pathway has not been associated with juvenile hormone pathway previously. We will next test to see if mutations in just these genes increase methoprene sensitivity. This study supports the hypothesis that natural variation alters drug sensitivity.
Many people take ibuprofen, the anti-inflammatory drug, and do not understand the process that occurs in the body. Ibuprofen is sold as a racemic mixture. The R enantiomer is the inactive conformer while the S enantiomer is the active conformer. Ibuprofen inhibits inflammation but also undergoes isomerisation. This process occurs when the (R)-ibuprofen isomerises to the (S)- ibuprofen. Isomerisation can also happen in both polar and non-polar solvents indicating that the solvents do not affect whether isomerisation occurs. This may indicate that the process requires an intramolecular reaction to occur. The process of the isomerisation of ibuprofen is not fully understood.
Using computational means, three types of possible intramolecular mechanism were found. These mechanisms were used to determine the possible way in which ibuprofen isomerises. The keto–enol tautomerism mechanism requires 73 kcals/mol. The mechanism that contains a hydrogen transfer to the benzene ring requires 80 kcals/mol. The last mechanism requires an inversion at the chiral centre and is much higher than 109 kcals/mol. The keto–enol tautomerism mechanism requires the least amount of energy and is thus the most feasible out of the three intramolecular pathways. Each mechanism is of very high energy and therefore there must be another means to which isomerisation occurs. Future research includes looking at acid catalyst reactions and studying the effects that tunnelling may have on the isomerisation of ibuprofen.
This research paper attempts to investigate the criteria used by donor states to allocate Official Development Assistance (ODA) which is defined as all grants and concessional loans with a minimum 25% grant element. The study combines the datasets created by Alesina and Dollar (2000) and Dreher and Fuchs (2011), covering aid streams between 1960–1995 from nine different donors.
To account for the shortcomings of the existing literature, rather than assessing recipient need and donor interest variables separately, this paper adopts a hybrid model that includes both types of variables. Moreover, this study accounts for the left-censored nature of ODA – donors often allocate zero aid due to resources constraints – by employing a Tobit I model. This type of regression analysis describes a one stage process, where the donor country decides between allocating a positive or zero amount of aid to a given recipient, ceteris paribus.
Subsequent results invalidate some of the existing conclusions and show that altruistic considerations play a significant role when explaining aid outflows. Notably, the US appears to be more altruistic than it has previously been suggested. Nonetheless, findings also exhibit important differences across donors, with some of them attaching a great deal of importance to their own political or economic interests. For instance, most donors tend to favour their former colonies or political allies such as Egypt. Thus, this paper supports the view that aid effectiveness might be partially undermined by a donor interest bias, although this bias might be smaller than previously suggested.