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1.
Beilstein J Org Chem ; 18: 120-132, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35116082

RESUMO

There have been several studies on the solvolysis mechanisms for alkanesulfonyl chlorides (RSO2Cl) and arenesulfonyl chlorides (ArSO2Cl). The earlier of these studies were reviewed a little over thirty years ago by Gordon, Maskill and Ruasse (Chem. Soc. Rev. 1989, 18, 123-151) in a contribution entitled "Sulfonyl Transfer Reactions". The present review will emphasize more recent contributions and, in particular, the application of the extended Grunwald-Winstein equation and kinetic solvent isotope effects to the solvolysis reactions. There is also an appreciable number of reports concerning the corresponding anhydrides with the chloride leaving group replaced by the appropriate sulfonate leaving group, concerning sulfamoyl chlorides (ZZ'NSO2Cl) with Z and Z' being alkyl or aryl and concerning the solvolysis of chlorosulfate esters (alkoxy- or aryloxysulfonyl chlorides), with the structures ROSO2Cl or ArOSO2Cl. The solvolyses of these additional types of sulfur(VI) substrates will be the topics of a future review.

2.
J Educ Elearn Res ; 7(4): 407-420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33263099

RESUMO

During the COVID-19 pandemic, with very little preparation and within a brief span of 48 hours, the Wesley College STEM faculty and students triaged into a remote-only form of instruction. Wesley College STEM student COVID-19 impact surveys showed underlying gaps in economic equity, increased family responsibilities, struggles to stay motivated, social isolation, and higher levels of psychological stress. Yet, the crisis demonstrated new ways in which technology can be harnessed and allowed STEM students to reconsider how jobs and skills should be aligned. A STEM faculty COVID-19 check-in survey and interview responses revealed a quick realization that faculty could not rely solely on Wesley's Jenzebar learning management system (MyWesley). To engage their students and to create a supportive learning environment, STEM faculty sought new strategies and approaches for a diverse set of STEM learners. For synchronous e-teaching, the faculty used the Microsoft-Teams and the Zoom video conferencing platforms. Faculty only adopted MyWesley to execute dedicated asynchronous tasks (laboratory assignments, reports, exams). The STEM students were overwhelmingly positive about STEM faculty availability during the crisis. Still, both faculty and students indicated a much stronger preference for the face-to-face delivery of their course content via a traditional classroom setting.

3.
Res Health Sci ; 5(4): 46-59, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33163825

RESUMO

The U.S. alcohol-attributable mortality burden makes it the third-leading cause of preventable deaths. This 1999-2018 observational study used the Tenth Revision of the International Classification of Diseases codes and the alcohol-related disease impact (ARDI) causes of death records to track alcohol's mortality burden. The Centers for Disease Control and Prevention keeps Wide-Ranging Online Data for Epidemiologic Research (WONDER) death certificates for the U.S. community. Evidence indicates that the U.S. ARDI mortality rates progressively trended upward (53.73%). Men were three times as likely as women to die, but female mortality rate changes (90.03%) advanced more rapidly than males. The study also revealed that the changes in alcohol-related death rate percentages for middle-age groups increased faster. In contrast, the African American/Black (AA/B) community's age-adjusted mortality rate change patterns first declined and then increased. The alcohol-attributable mortality rate (1999 to 2018) difference for AA/B was -6.35%. Delaware's population is around one million, and about 23% is African American/Black. The subgroup analysis for Delaware's population was robust and showed alcohol-attributable mortality rates above national averages. This trend was apparent for both gender and race. In conclusion, for both the U.S. and Delaware, alcohol use disorder is a risk factor for mortality, especially for males.

4.
Int J Mol Sci ; 21(12)2020 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-32575637

RESUMO

A previous study of the effect of a 2-chloro substituent on the rates and the mechanisms of the solvolysis of ethyl chloroformate is extended to the effect of a 3-chloro substituent on the previously studied solvolysis of propyl chloroformate and to the effect of a 4-chloro substituent on the here reported rates of solvolysis of butyl chloroformate. In each comparison, the influence of the chloro substituent is shown to be nicely consistent with the proposal, largely based on the application of the extended Grunwald-Winstein equation, of an addition-elimination mechanism for solvolysis in the solvents of only modest solvent ionizing power, which changes over to an ionization mechanism for solvents of relatively high ionizing power and low nucleophilicity, such as aqueous fluoroalcohols with an appreciable fluoroalcohol content.


Assuntos
Cloro/química , Formiatos/química , Radical Hidroxila/química , Cinética , Estrutura Molecular , Solventes/química
5.
Res Health Sci ; 4(4): 327-346, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31768484

RESUMO

Using commercially available but powerful big data analytics, this non-clinical obesity and underlying causes of death observational study, analyzed the very large US Centers for Disease Control and Prevention's (CDC) State of Obesity records, the CDC WONDER data, and the US census records. Compared to the 1999-to-2017 US obesity rate increase of 29.8%, an uncontrolled increase in Delaware's obesity rate (81.7%) was observed. During the same time period, CDC WONDER death certificate archives disclosed that there was a 60.53% surge in crude Delawarean mortality rate when obesity was listed as a single underlying cause of death. When any mention of obesity was documented on the death certificate, Delaware's 1999-2017 crude mortality rate advanced by 75.69% and its age-adjusted rate rose by 53.18%. Likewise, except for one year, Delaware's African American/Black population experienced higher crude mortality rate averages but however, between the years of 1997 and 2017, its Caucasian/White inhabitants had an enormous 87.34% death rate increase. With additional available CDC mortality data, Delaware males saw substantially larger age-adjusted death rate increases (79.87%) than their female counterparts (28.92%). Diabetes, circulatory system diseases, and neoplasms (cancer), are three common obesity comorbidities. For these three conditions, Delaware's 1999-2017 mortality rate figures mimic the falling national patterns of mortality rate averages, when each disease is listed as the single underlying cause of death, including observations where there are disproportionate numbers of cases that affect the African American/Black race.

6.
IEEE Netw ; 2019: 1-6, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31631939

RESUMO

In the US, cardiovascular disease, cancer, and diabetes are in the top ten leading causes of death categories. The diseases compromise US life-expectancy and account for significant US health-care costs. This observational study investigates the US population's 1997-2017 Centers for Disease Control and Prevention (CDC) WONDER ICD-10 mortality records to extract the prevalence rates for leading causes of death by diabetes, neoplasms (cancers), and diseases of the circulatory system. The variables of race and age are examined for each disease in order to evaluate demographic and age-group risks. To document the public health burden from these three chronic conditions, mortality data from CDC WONDER was analyzed using MS-Excel and Statistical Analysis System (SAS) software. The general trend of deaths by diabetes, neoplasms, and diseases of the circulatory system has been progressively decreasing nationally; however, a significantly higher trend in mortality rates is observed for the Black or African American populations. Furthermore, over the 1997-2017 observational period, the crude mortality rates for the 45-54 (middle-age) and lower age-groups are below national mortality rate averages but are troublingly increasing for diabetes and notably, for the diseases of the circulatory system, the (younger) 25-34 age-group had a crude mortality rate increase of 6.78%.

7.
Artigo em Inglês | MEDLINE | ID: mdl-31535095

RESUMO

Wesley College is Delaware's minority-serving, private, undergraduate, liberal-arts institution1. The College continually advances innovative programming to boost college readiness and to stem the dropping numbers of its first-time (freshmen) applicants. In order to help unprepared students for the rigors of its programs and to enhance a truly integrated STEM curriculum2-8, Wesley strengthened diverse academic equity by implanting data-science as cornerstone undergraduate research projects9-11. To further scale-up student-engagement and to nationally disseminate our high-impact STEM-education successes12,13, the College developed an Undergraduate Research Center for Analytics, Talent, and Success (UR-CATS)14. To streamline procurement documents and hazardous-waste handling workflows, the College implemented the use of an online platform15 that resulted in major annual savings. To engage middle and high school students, Wesley STEM undergraduates established a Science Club to demonstrate hands-on science lessons, so STEM concepts come to life. To help explain the learning mechanisms by which integrated STEM experiences support outcomes, this paper presents interventions with particular attention to curriculum design for incoming STEM freshmen who place into pre-Calculus or a lower math course. To show that engagement with STEM college students as role models have a positive impact on high-school student interest, we provide examples where Science Club members pose challenges and show different perspectives on everyday items. In summary, Wesley project outcomes have allowed for coordinated interventions3-9,12-14 in student well-being and student success.

8.
Res Health Sci ; 3(3): 65-78, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30079383

RESUMO

BACKGROUND: In the US, obesity is an epidemiologic challenge and the population fails to comprehend this complex public health issue. To evaluate underlying obesity-impact patterns on mortality rates, we data-mined the 1999-2016 Center for Disease Control WONDER database's vital records. METHODS: Adopting SAS programming, we scrutinized the mortality and population counts. Using ICD-10 diagnosis codes connected to overweight and obesity, we obtained the obesity-related crude and age-adjusted causes of death. To understand divergent and prevalence trends we compared and contrasted the tabulated obesity-influenced mortality rates with demographic information, gender, and age-related data. KEY RESULTS: From 1999 to 2016, the obesity-related age-adjusted mortality rates increased by 142%. The ICD-10 overweight and obesity-related death-certificate coding showed clear evidence that obesity factored in the male age-adjusted mortality rate increment to 173% and the corresponding female rate to 117%. It also disproportionately affected the nation-wide minority population death rates. Furthermore, excess weight distributions are coded as contributing features in the crude death rates for all decennial age-groups. CONCLUSIONS: The 1999-2016 data from ICD-10 death certificate coding for obesity-related conditions indicate that it is affecting all segments of the US population.

9.
J STEM Educ ; 19(1): 31-40, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057516

RESUMO

Wesley College secured a five-year National Science Foundation (NSF) S-STEM (scholarships in science, technology, engineering, and mathematics) grant (1355554) to provide affordability and access to its robust STEM programs. With these funds, the college initiated a freshman to senior level, mixed-cohort, Cannon Scholar (CS) learning community (LC). Around the proven high-impact practice of multi-tiered mentoring, this LC is designed for greater commitment to participating STEM undergraduates. It truly is a collaborative effort between faculty and administrators. For Scholars interested in mentored research, existing NSF Experimental Program to Stimulate Competitive Research, and National Institutes of Health, National Institute of General Medical Sciences - IDeA Networks of Biomedical Research Excellence funding, complement the innovation and cross-disciplinary collaborations in the CS programming. This enriches and further supports the CS LC. Throughout the 2014-2016 program duration, there were 66 unique scholarship recipients and 82% participated in directed research. Fifty-nine percent were from underrepresented minority populations and 65% were female. Ninety-five percent of these Scholars were retained and 100% of the graduates (n = 21) entered STEM fields. Analyses controlled for population similarity proves that with an intensive focus on academic support, high-impact uplifting practices were implemented through a framework of comprehensive student engagement activities. Such strategic interactions resulted in higher overall GPAs and significantly improved Scholar retention rates.

10.
Trends Org Chem ; 19: 1-11, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30740002

RESUMO

The experimentally measured rates of solvolysis of 2-chloroethoxycarbonyl chloride (2-chloroethyl chloroformate, 3), 2-chloroethoxycarbonyl p-toluenesufonate (5), and phenoxycarbonyl p-toluenesulfonate (6) were followed at 25.0 °C in various pure and binary aqueous-organic solvents with varying degrees of polarity. An analysis of the rate constants for 3, 5, and 6, was carried out using the two-term extended Grunwald-Winstein equation and comparisons are made to the previously published results for ethyl and phenyl chloroformate esters. The k OTS/k Cl rate ratios and the Grunwald-Winstein l/m ratios indicate the probability of a dominant bimolecular carbonyl-addition pathway in the more nucleophilic solvents. Nevertheless in 3 and 5, in the strongly hydrogen-bonding 70% and 50% HFIP mixtures, a side-by-side ionization mechanism is favored.

11.
Int J Adv Sci Eng Technol ; 5(3): 25-29, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29251298

RESUMO

To develop best practices for laboratory safety and for chemical product and supplies management accountability, the freely-available online platform, Quartzy, was integrated within an interdisciplinary science department at a small Mid-Atlantic liberal-arts college. This was done to ensure the accuracy of purchase records, the appropriate use of storage and handling protocols, and for a continually updated chemical inventory system. Quartzy also facilitated the digital tracking and dispersal of the College's hazardous waste inventory. Since the implementation of the Quartzy platform, the science department achieved significant cost-savings during the procurement of laboratory supplies and equipment, and it developed a sense of ownership towards the common goal of lowering the College's environmental impact as it relates to its managing of laboratory-generated hazardous wastes.

12.
Am J Health Sci ; 8(1): 19-32, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28690914

RESUMO

As Delaware's adult obesity crisis continues to be a leading public health concern, we evaluated Delaware's 1999-2014 vital records to examine the association between obesity and mortality. We used the Delaware population death records from the Centers for Disease Control and Prevention (CDC) WONDER database and the Delaware Health Statistics Center (DHSC). Together with the vital records, we incorporated Microsoft Excel, SAS (Statistical Analysis System) and GIS (geographic information system) tools to analyze obesity influences from county residence, economic status, education, gender, and race. Using the 15-year (1999-2014) time span with the CDC WONDER database, we observed a statistically significant 28.7% increase in the age-adjusted Delaware obesity-related mortality rates (where obesity was a contributory factor). Furthermore, obesity influenced death counts in all three Delaware counties (New Castle, Kent, and Sussex). Kent County experienced the largest increase (66.0%), followed by New Castle County (47.4%), and Sussex County (25.2%). The DHSC mortality rates for all leading causes of death from 2000 to 2011 indicated relatively stable mortality rates for Delaware. However, using CDC WONDER data, the Delaware mortality rate for obesity as a single underlying cause in 2011 was 56.9% higher than mortality rate in 2000.

13.
J Coll Teach Learn ; 13(2): 47-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27064213

RESUMO

In 2014 Wesley College adopted a unified undergraduate program of evidence-based high-impact teaching practices. Through foundation and federal and state grant support, the college completely revised its academic core curriculum and strengthened its academic support structures by including a comprehensive early alert system for at-risk students. In this core, science, technology, engineering, and mathematics (STEM) faculty developed fresh manifestations of integrated concept-based introductory courses and revised upper-division STEM courses around student-centered learning. STEM majors can participate in specifically designed paid undergraduate research experiences in directed research elective courses. Such a college-wide multi-tiered approach results in institutional cultural change.

14.
Int J Mol Sci ; 17(1)2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26784185

RESUMO

Carbamoyl chlorides are important intermediates, both in the research laboratory and in industrial scale syntheses. The most studied and used are the disubstituted derivatives, incorporating either aryl or alkyl groups (Ar2NCOCl or R2NCOCl). Sometimes, the groups are tied back to give a ring and piperidino- and morpholino-derivatives are commonly encountered. Some studies have been made with two different groups attached. Solvolyses tend to occur at the carbonyl carbon, with replacement of the chloride ion. Studies of both rate and products are reviewed and the solvolysis reactions are usually SN1, although addition of an amine leads to a superimposable bimolecular component. Many of the studies under solvolytic conditions include the application of the extended Grunwald-Winstein equation. The monosubstituted derivatives (ArNHCOCl or RNHCOCl) are less studied. They are readily prepared by the addition of HCl to an isocyanate. In acetonitrile, they decompose to set up and reach equilibrium with the isocyanate (ArNCO or RNCO) and HCl. Considering that the structurally related formyl chloride (HOCOCl) is highly unstable (with formation of HCl + CO2), the unsubstituted carbamoyl chloride (H2NCOCl) is remarkably stable. Recommended synthetic procedures require it to survive reaction temperatures in the 300-400 °C range. There has been very little study of its reactions.


Assuntos
Ácidos Carboxílicos/química , Técnicas de Química Sintética/métodos , Cloretos/química , Solventes/química
15.
... Int Conf Ind Instrum Control ; 2015: 71-76, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26478918

RESUMO

Synthetic pesticides are widely used in the modern world for human benefit. They are usually classified according to their intended pest target. In Delaware (DE), approximately 42 percent of the arable land is used for agriculture. In order to manage insectivorous and herbaceous pests (such as insects, weeds, nematodes, and rodents), pesticides are used profusely to biologically control the normal pest's life stage. In this undergraduate project, we first created a usable relational database containing 62 agricultural pesticides that are common in Delaware. Chemically pertinent quantitative and qualitative information was first stored in Bio-Rad's KnowItAll® Informatics System. Next, we extracted the data out of the KnowItAll® system and created additional sections on a Microsoft® Excel spreadsheet detailing pesticide use(s) and safety and handling information. Finally, in an effort to promote good agricultural practices, to increase efficiency in business decisions, and to make pesticide data globally accessible, we developed a mobile application for smartphones that displayed the pesticide database using Appery.io™; a cloud-based HyperText Markup Language (HTML5), jQuery Mobile and Hybrid Mobile app builder.

16.
Artigo em Inglês | MEDLINE | ID: mdl-26191337

RESUMO

Wesley College is a private, primarily undergraduate minority-serving institution located in the historic district of Dover, Delaware (DE). The College recently revised its baccalaureate biological chemistry program requirements to include a one-semester Physical Chemistry for the Life Sciences course and project-based experiential learning courses using instrumentation, data-collection, data-storage, statistical-modeling analysis, visualization, and computational techniques. In this revised curriculum, students begin with a traditional set of biology, chemistry, physics, and mathematics major core-requirements, a geographic information systems (GIS) course, a choice of an instrumental analysis course or a statistical analysis systems (SAS) programming course, and then, students can add major-electives that further add depth and value to their future post-graduate specialty areas. Open-sourced georeferenced census, health and health disparity data were coupled with GIS and SAS tools, in a public health surveillance system project, based on US county zip-codes, to develop use-cases for chronic adult obesity where income, poverty status, health insurance coverage, education, and age were categorical variables. Across the 48 contiguous states, obesity rates are found to be directly proportional to high poverty and inversely proportional to median income and educational achievement. For the State of Delaware, age and educational attainment were found to be limiting obesity risk-factors in its adult population. Furthermore, the 2004-2010 obesity trends showed that for two of the less densely populated Delaware counties; Sussex and Kent, the rates of adult obesity were found to be progressing at much higher proportions when compared to the national average.

17.
J Coll Teach Learn ; 12(3): 195-208, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26185487

RESUMO

Church-related small private liberal arts baccalaureate minority-serving institutions like Wesley College have modest endowments, are heavily tuition-dependent, and have large numbers of financially-challenged students. In order to sustain the level of academic excellence and to continue to build student demographic diversity in its accessible robust Science and Mathematics (STEM) programs, the faculty sought federal and state funds to implement a coordinated program of curriculum enhancements and student support programs that will increase the number of students choosing STEM majors, increase their academic success, and improve retention.

18.
Am J Health Sci ; 6(1): 59-74, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26064779

RESUMO

The 2010 Centers for Disease Control and Prevention (CDC) report indicates that 63.4% of Delaware's adult population is overweight and 28% is obese. Here, the authors reveal analyses acquired from detailed investigations about the importance of gender, and other lifestyle factors and behaviors on the Body Mass Index (BMI) trends amongst an indiscriminate sample of the Wesley College (Wesley) undergraduate population. A 25-question paper-format survey was distributed to 307 randomly chosen Wesley undergraduates. The accrued qualitative (or categorical) data were transferred to an Excel spreadsheet to construct and observe frequency distributions. A Chi-square test of independence (χ2) was performed between BMI status (normal, overweight, obese) and the following factors: gender, diet plan, adherence to the United States Department of Agriculture (USDA) MyPlate nutrition guide, use of the seasonal flu shot, weekly workout schedule, supplement usage, participation on athletic teams, questioning of label nutritional facts, and the use of added salt in food. A 2-sample proportion test was performed between students who were overweight or obese for the same factors. Also performed were t-tests for mean BMI for those who followed USDA MyPlate guidelines and for those who did not. An analysis of 278 completed surveys show that 29.5% of the Wesley respondents are overweight and 19.8% are obese. The mean BMI for males was statistically higher than the mean BMI for females. The mean BMI for students living on-campus was statistically higher than the mean BMI for students living off-campus. The results also demonstrate that adhering to the USDA dietary recommendations for fruit and dairy can be important factors in reducing the risk of obesity.

19.
J Anal Methods Chem ; 2015: 941638, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25767738

RESUMO

The solvolysis of 4,5-dimethoxy-2-nitrobenzyl chloroformate (NVOC-Cl, 1) is followed at 25.0°C in twenty hydroxylic solvents. A comparison with previously published rates for benzyl chloroformate and p-nitrobenzyl chloroformate indicates that the inductive effect of the nitro and the two methoxy groups strongly influences the rate of reaction. For 1, the specific rates of solvolysis are correlated using an extended Grunwald-Winstein (G-W) treatment. A direct comparison with the data for phenyl chloroformate (PhOCOCl) in identical solvents strongly suggests that the addition step within an addition-elimination mechanism is rate-determining for both substrates. A reevaluation of the kinetic data for 9-fluorenylmethyl chloroformate (FMOC-Cl, 2) involves a correlation of log⁡(k/k o )2 versus log⁡(k/k o )PhOCOCl. In this plot, deviations were observed in solvents rich in a hydrogen-bonding fluoroalcohol component. Omitting the aqueous fluoroalcohol rate measurements for 2 in an analysis using the extended G-W equation suggested the occurrence of dual pathways differing in the dependences upon the ionizing power and nucleophilicity of the solvent. In addition, the fluorenyl ring is rotated out of the plane containing the ether oxygen and, as a result, PhOCOCl is found to solvolyze 20 times faster than 2 in ethanol and methanol.

20.
Int J Mol Sci ; 15(10): 18310-32, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25310653

RESUMO

The replacement of oxygen within a chloroformate ester (ROCOCl) by sulfur can lead to a chlorothioformate (RSCOCl), a chlorothionoformate (ROCSCl), or a chlorodithioformate (RSCSCl). Phenyl chloroformate (PhOCOCl) reacts over the full range of solvents usually included in Grunwald-Winstein equation studies of solvolysis by an addition-elimination (A-E) pathway. At the other extreme, phenyl chlorodithioformate (PhSCSCl) reacts across the range by an ionization pathway. The phenyl chlorothioformate (PhSCOCl) and phenyl chlorothionoformate (PhOCSCl) react at remarkably similar rates in a given solvent and there is a dichotomy of behavior with the A-E pathway favored in solvents such as ethanol-water and the ionization mechanism favored in aqueous solvents rich in fluoroalcohol. Alkyl esters behave similarly but with increased tendency to ionization as the alkyl group goes from 1° to 2° to 3°. N,N-Disubstituted carbamoyl halides favor the ionization pathway as do also the considerably faster reacting thiocarbamoyl chlorides. The tendency towards ionization increases as, within the three contributing structures of the resonance hybrid for the formed cation, the atoms carrying positive charge (other than the central carbon) change from oxygen to sulfur to nitrogen, consistent with the relative stabilities of species with positive charge on these atoms.


Assuntos
Ésteres do Ácido Fórmico/química , Oxigênio/química , Enxofre/química , Halogenação , Solventes/química , Compostos de Sulfidrila/química
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