The Journal of Undergraduate Research最新文献_第2页

9-Borobicyclo[3.3.1]nonane-Catalyzed Hydroboration of Terminal Aromatic Alkynes with Pinacolborane 9-硼双环[3.3.1]壬烷催化末端芳烃与蒎烷硼烷的硼氢化反应

The Journal of Undergraduate Research Pub Date : 2020-06-28 DOI: 10.33697/ajur.2020.011

Garett Ruesch, S. Rowley, M. Mifflin, N. Werner

{"title":"9-Borobicyclo[3.3.1]nonane-Catalyzed Hydroboration of Terminal Aromatic Alkynes with Pinacolborane","authors":"Garett Ruesch, S. Rowley, M. Mifflin, N. Werner","doi":"10.33697/ajur.2020.011","DOIUrl":"https://doi.org/10.33697/ajur.2020.011","url":null,"abstract":"Organoboron compounds are extensively used in organic synthesis. The alkenylboronic acid pinacol esters formed from the hydroboration reaction of alkynes with pinacolborane are stable, easy to handle, and useful in many synthetic transformations. However, pinacolborane lacks the reactivity necessary to undergo facile hydroboration reaction with terminal aromatic alkynes. 9Borobicyclo[3.3.1]nonane (9-BBN) can be used to catalyze the hydroboration reaction of phenylacetylene with pinacolborane. The hydroboration reaction parameters and product purification conditions were evaluated to maximize the yield of (E)-2phenylethenylboronic acid pinacol ester. It was found that the optimal reaction conditions for the 9-BBN-catalyzed hydroboration of phenylacetylene with pinacolborane were: phenylacetylene (1.0 equiv), pinacolborane (1.2 equiv), 9-BBN (20 mol%), and THF [0.2] at 65 °C. The compatibility of these reaction conditions with p-substituted terminal aromatic alkynes bearing electronically diverse groups was studied. Moderate to good yield (49–76%) of the hydroboration products were isolated after purification by liquid-liquid extraction and flash chromatography.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"30 1","pages":"3-12"},"PeriodicalIF":0.0,"publicationDate":"2020-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77755967","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Editorial Issue 13.1 社论第13.1期

The Journal of Undergraduate Research Pub Date : 2020-05-04 DOI: 10.31273/reinvention.v13i1.630

Polina Zelmanova

引用次数: 0

Reinvention: Building a future from our past 重塑:在过去的基础上创造未来

The Journal of Undergraduate Research Pub Date : 2020-04-29 DOI: 10.31273/reinvention.v13i1.631

Polina Zelmanova

引用次数: 0

Women’s Representation in the Post-Soviet Space: Latvia and Lithuania 后苏联空间中的妇女代表:拉脱维亚和立陶宛

The Journal of Undergraduate Research Pub Date : 2020-04-29 DOI: 10.31273/reinvention.v13i1.559

A. Beam

{"title":"Women’s Representation in the Post-Soviet Space: Latvia and Lithuania","authors":"A. Beam","doi":"10.31273/reinvention.v13i1.559","DOIUrl":"https://doi.org/10.31273/reinvention.v13i1.559","url":null,"abstract":"Using a most-similar case design to compare Latvia and Lithuania, this study examines the role electoral systems play in affecting greater representation of women in post-Soviet democracies. After Latvia’s most recent election, Latvia demonstrated a much higher percentage of women in its parliament (31%) than Lithuania (21%). Interestingly, in spite of having higher descriptive representation, Latvia has no quotas or women's organizations/caucuses while Lithuania implements voluntary quotas and has a prevalent women's caucus. This study advances an institutional argument, hypothesizing that the Latvian parliament's higher percentage of women can be attributed to its proportional representation electoral system. Lithuania has a mixed system that has favored a majoritarian pole, which in turn, has adversely affected women’s electoral success. In many ways, women’s substantive representation in Latvia and Lithuania is only marginally different. However, in regard to the sheer number of women in parliament, the difference between Lithuania and Latvia proves relatively marked. The Latvian and Lithuanian cases demonstrate that proportional representation electoral systems are more favorable to women candidates than mixed systems, even in the absence of quotas and a women’s movement and particularly in the context of post-Soviet democracies","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81895053","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spermidine and its role in inducing autophagy in cardiac muscle to prevent cardiac dysfunction 亚精胺及其诱导心肌自噬预防心功能障碍的作用

The Journal of Undergraduate Research Pub Date : 2020-04-28 DOI: 10.31273/reinvention.v13i1.519

I. Hassan, Leda Mirbahai

{"title":"Spermidine and its role in inducing autophagy in cardiac muscle to prevent cardiac dysfunction","authors":"I. Hassan, Leda Mirbahai","doi":"10.31273/reinvention.v13i1.519","DOIUrl":"https://doi.org/10.31273/reinvention.v13i1.519","url":null,"abstract":"Ageing is one of the most critical risk factors in the development of age-related disease. In particular, it is associated with an increased risk of cardiovascular disease with age-related changes to the heart demonstrating hypertrophy, reduced elasticity and reduced diastolic function. The dietary implementation of the polyamine spermidine has been shown to extend lifespan in a number of model organisms such as mice, rats, yeast, worms, flies and mammals, thought primarily to be due to its cardioprotective effects. Various studies have demonstrated the ability of spermidine to reduce blood pressure, delay hypertrophy and increase elasticity of cardiac muscle. Spermidine is a polyamine that is naturally abundant in a number of foods such as aged cheese, fermented soybean and wheatgerm, making it a viable compound to research its impact on longevity through dietary interventions. Spermidine has the ability to promote autophagy in cardiac muscle along with mitophagy. Autophagy is a vital process for the recycling of dysfunctional and potentially harmful cellular components which can prevent interruptions in the homeostatic environment and prevent disease. In light of the cardioprotective effects seen through spermidine supplementation in various models, it is a promising candidate for further research into treatments for age-related cardiac decline.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83376579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Discounting Beyond Death 死亡后贴现

The Journal of Undergraduate Research Pub Date : 2020-04-25 DOI: 10.31273/reinvention.v13i1.491

Lieke Voorintholt

{"title":"Discounting Beyond Death","authors":"Lieke Voorintholt","doi":"10.31273/reinvention.v13i1.491","DOIUrl":"https://doi.org/10.31273/reinvention.v13i1.491","url":null,"abstract":"How do people value the welfare of future generations? This question is of special importance now that future generations’ welfare is at stake because of expected climate change. This paper looks into people’s preferences regarding intergenerational distribution of welfare. It replicates research on the discounting of life saving and uses a new question that aims to measure the valuation of future generations’ standard of life. Data is obtained from an online questionnaire (N = 138) and shows values for the discount factors that indicate decreasing valuation of future welfare. Heterogeneity is observed in distributions between one’s descendants and between future generations in general. This might be explained by the superiority of either kinship-related or ethical motives that would differ for both sorts. Obtained discount factors possibly reflect decreasing connectedness to generations over time, until the point where such generations are considered strangers and no further discounting takes place. The effect of major life events such as grandparenthood also fit this explanatory framework. Changes in demographic factors could therefore translate to changes in intergenerational discounting. Exact predictions of these and other relationships should be confirmed by further research.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89675745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of Sleeping Duration on the Risk of Breast Cancer: A Systematic Review and Meta-Analysis of Population-Based Cohort Studies 睡眠时间对乳腺癌风险的影响:基于人群队列研究的系统回顾和荟萃分析

The Journal of Undergraduate Research Pub Date : 2020-04-19 DOI: 10.31273/reinvention.v13i1.530

Amos Ochieng Okutse

{"title":"Impact of Sleeping Duration on the Risk of Breast Cancer: A Systematic Review and Meta-Analysis of Population-Based Cohort Studies","authors":"Amos Ochieng Okutse","doi":"10.31273/reinvention.v13i1.530","DOIUrl":"https://doi.org/10.31273/reinvention.v13i1.530","url":null,"abstract":"Background: The impact of different sleeping categories on the risk of cancer of the breast has remained debatable. We sought to systematically synthesize the fund of available literature on this relationship from population-based cohort studies using meta-analytic procedures. \u0000Data sources: Studies about napping and cancer of the breasts were identified from databases up to February 2019. \u0000Methods: Identified studies were analyzed for quality using NOS Scores. Effect sizes were visualized using funnel plots. Study heterogeneity was quantified using I2 and visualized using Baujat plots. Publication prejudice was evaluated using Eggers regression model, with visualizations using funnel plots. Analysis were done using R. \u0000Results: Eight cohort studies met the inclusion criteria. Random effects model revealed non-statistically significant evidence of an association between short or long sleep and breast cancer OR=0.90;(95%CI 0.7995-1.0215); p=0.1054 and OR=0.95(0.8886-1.0280);p=0.2234 respectively. There was moderate to high heterogeneity I2(95%CI)=74.4%(48.2%-87.4%) among studies examining short sleep and cancer of the breast, and low to moderate heterogeneity in studies for long sleep and breast cancer I2(95%CI)=3.0%(0.0%-68.6%). \u0000Conclusions: This study found non substantial evidence of associations between sleeping periods and cancer of the breast in women. Studies employing novel sleep measurement methodologies should be carried out to examine the underlying relationship.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81148372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dining and Dying at Pompeii : Last Supper at Pompeii Exhibition Review 在庞贝的用餐和死亡:庞贝最后的晚餐展览评论

The Journal of Undergraduate Research Pub Date : 2020-04-07 DOI: 10.31273/reinvention.v13i1.587

I. Green, Shayni Solanki, Archie Green, S. Young, Megan Woodberry, O. Fanti, Rhianna Pike, Georgia Brown

引用次数: 0

Exhibition Review: Last Supper in Pompeii - too much death not enough food 展览评论:最后的晚餐在庞贝-太多的死亡没有足够的食物

The Journal of Undergraduate Research Pub Date : 2020-04-07 DOI: 10.31273/reinvention.v13i1.588

Edward L. Summers, S. Nawaz, Elysia Dale, G. Seager, P. Novis, M. Coster, M. Jenkins, Cameron Hill, Daisy Sutherland

引用次数: 0

Myriad-Briefing Myriad-Briefing

The Journal of Undergraduate Research Pub Date : 2020-03-24 DOI: 10.31273/reinvention.v13i1.488

P. D. W. Banks

{"title":"Myriad-Briefing","authors":"P. D. W. Banks","doi":"10.31273/reinvention.v13i1.488","DOIUrl":"https://doi.org/10.31273/reinvention.v13i1.488","url":null,"abstract":"Briefing a participant is necessary to obtain informed consent. However, briefing can change a participant’s behaviour; for example, knowledge of an upcoming memory test might cause you to attend experimental stimuli more so that you look clever in the test. Studies that try to measure natural behaviour therefore use deception to avoid this behaviour change. This merely flips the problem from a methodological one to an ethical one. This paper guides future research of a potential solution: myriad-briefing is a technique of presenting a collection of possible tasks to ambiguate the nature of the experiment so that participants consent to the experimental tasks without knowing what the experiment will involve. Before more extensive investigation of the application of myriad-briefing, this paper investigated two salient caveats. Part 1 obtains feedback from participants about myriad-briefing to see if more information deters participation. Results find no negative effect of myriad-briefing on participant willingness to participate. Part 2 tests whether participants pay attention to myriad briefing in online studies to see if the technique is applicable. Results find that too few participants read the briefing to produce an observable effect suggesting myriad-briefing is best applied to laboratory settings.","PeriodicalId":22986,"journal":{"name":"The Journal of Undergraduate Research","volume":"96 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82768620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0