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1.
J Acad Nutr Diet ; 124(6): 747-756.e3, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38184230

RESUMO

BACKGROUND: The Supplemental Nutrition Assistance Program (SNAP) plays a critical role in alleviating poverty and food insecurity. Despite these benefits, many older Americans who are eligible for SNAP do not participate in the program. Few studies have explored household factors and food insecurity outcomes associated with nonparticipation among older Black Americans. OBJECTIVES: The study aim was to explore changes in food insecurity and related financial hardship outcomes between 2020 and 2021 among SNAP participants, eligible nonparticipants, and ineligible nonparticipants; compare reasons for not participating in SNAP; and to compare household factors associated with SNAP nonparticipation. METHODS: Longitudinal design examining data from 2020 and 2021 to assess changes in food insecurity over the course of the coronavirus disease 2019 pandemic. PARTICIPANTS/SETTING: Participants were 528 adults (aged 30 to 97 years) in households randomly selected from a listing of all residential addresses in two predominantly Black neighborhoods with lower incomes in Pittsburgh, PA, and surveyed between March to May 2020 and May to December 2021. MAIN OUTCOME MEASURES: Food security was measured using the validated 6-item US Department of Agriculture Adult Food Security Survey Module. STATISTICAL ANALYSES PERFORMED: Findings are based on a descriptive analysis of food security and related indicators. Statistical testing was performed to assess differences between SNAP participation status and individual characteristics, food security, and financial hardship using Wald F test for continuous measures and Pearson χ2 test for categorical measures. A multivariable linear model was used to assess the association of SNAP participation and eligibility status with change in food insecurity. RESULTS: In cross-sectional analyses of 2021 data, no differences were observed between SNAP participants and eligible nonparticipants for food insecurity, food bank use, mean weekly food spending per person, and difficulty paying for basics. However, with respect to changes in food insecurity over the course of the pandemic, SNAP participants experienced a greater improvement in mean food security scores between 2020 and 2021 (-0.52 reduction in mean food insecurity score or a 16% improvement in food security; P ≤ 0.05) relative to SNAP-eligible nonparticipants. Perceived ineligibility (71.3%) and perceived lack of need (23%) were the most common reasons for not participating in SNAP. CONCLUSIONS: More than one-third of SNAP participants and eligible nonparticipants experienced food insecurity and financial hardship. However, there were differences in the changes in food insecurity between these groups.


Assuntos
Negro ou Afro-Americano , COVID-19 , Assistência Alimentar , Insegurança Alimentar , Pobreza , Humanos , Assistência Alimentar/estatística & dados numéricos , Idoso , Feminino , Masculino , Pobreza/estatística & dados numéricos , Pessoa de Meia-Idade , COVID-19/etnologia , COVID-19/epidemiologia , Estudos Longitudinais , Negro ou Afro-Americano/estatística & dados numéricos , Idoso de 80 Anos ou mais , Adulto , Características de Residência , Pennsylvania/epidemiologia , SARS-CoV-2 , Abastecimento de Alimentos/estatística & dados numéricos , Abastecimento de Alimentos/economia
2.
Psychol Med ; 53(6): 2418-2426, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-34629132

RESUMO

BACKGROUND: The prevalence of serious psychological distress (SPD) was elevated during the COVID-19 pandemic in the USA, but the relationships of SPD during the pandemic with pre-pandemic SPD, pre-pandemic socioeconomic status, and pandemic-related social stressors remain unexamined. METHODS: A probability-based sample (N = 1751) of the US population age 20 and over was followed prospectively from February 2019 (T1), with subsequent interviews in May 2020 (T2) and August 2020 (T3). Multinomial logistic regression was used to assess prospective relationships between T1 SPD with experiences of disruption of employment, health care, and childcare at T2. Binary logistic regression was then used to assess relationships of T1 SPD, and socioeconomic status and T2 pandemic-related stressors with T3 SPD. RESULTS: At T1, SPD was associated with age, race/ethnicity, and household income. SPD at T1 predicted disruption of employment (OR 4.5, 95% CI 1.4-3.8) and health care (OR 3.2, 95% CI 1.4-7.1) at T2. SPD at T1 (OR 10.2, 95% CI 4.5-23.3), low household income at T1 (OR 2.6, 95% CI 1.1-6.4), disruption of employment at T2 (OR 3.2, 95% CI 1.4-7.6), and disruption of healthcare at T2 (OR 3.3, 95% CI 1.5-7.2) were all significantly associated with elevated risk for SPD at T3. CONCLUSIONS: Elevated risk for SPD during the COVID-19 pandemic is related to multiple psychological and social pathways that are likely to interact over the life course. Policies and interventions that target individuals with pre-existing mental health conditions as well as those experiencing persistent unemployment should be high priorities in the mental health response to the pandemic.


Assuntos
COVID-19 , Angústia Psicológica , Humanos , Adulto Jovem , Adulto , Pandemias , Estudos Longitudinais , COVID-19/epidemiologia , Estudos Prospectivos , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
3.
Nutrients ; 14(24)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36558400

RESUMO

Lack of geographic access to foods has been postulated as a cause for food insecurity, which has been linked to poor nutrition, obesity, and chronic disease. Building on an established cohort of randomly selected households from a low-income, predominantly Black neighborhood, we examined household food security, distance to where study participants reported doing their major food shopping, and prices at stores where they shopped. Data from the Pittsburgh Hill/Homewood Research on Eating, Shopping, and Health study for years 2011, 2014 and 2018 was limited to residents of the neighborhood that began as a food desert (i.e., low access to healthy foods), but acquired a full-service supermarket in 2013. We calculated descriptive statistics and compared study participants in the former food desert neighborhood whose food security improved to those whose food security did not improve across survey waves. We estimated cross sectional linear regressions using all waves of data to assess food security level among study participants. Distance to major food shopping store was positively associated with food security (p < 0.05) while food-store prices were not significantly associated with food security. Findings suggest that for predominantly low-income residents, food secure individuals traveled further for their major food shopping.


Assuntos
Desertos Alimentares , Abastecimento de Alimentos , Humanos , Estudos Transversais , Pobreza , Alimentos , Segurança Alimentar , Comércio
4.
Health Aff (Millwood) ; 41(11): 1645-1651, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36343311

RESUMO

We examined use of and willingness to use video telehealth during the COVID-19 pandemic in a longitudinally followed cohort. Between February 2019 and March 2021, use and willingness to use increased among nearly all subgroups, with large increases among Black adults and adults with lower educational attainment. In March 2021 Black adults, adults ages 20-39, and high-income adults reported the greatest willingness to use video telehealth.


Assuntos
COVID-19 , Telemedicina , Adulto , Humanos , Adulto Jovem , Pandemias/prevenção & controle , Estudos de Coortes
5.
Health Econ ; 31(9): 1844-1861, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35751857

RESUMO

While psychological distress is a common sequelae of job loss, how that relationship continued during the COVID-19 pandemic is unclear, for example, given higher health risk to working due to disease exposure. This paper examines changes in psychological distress depending on job loss among a cohort of randomly selected residents living in nine predominantly African American low-income neighborhoods in Pittsburgh PA across four waves between 2013 and 2020. Between 2013 and 2016, we found an increase in psychological distress after job loss in line with the literature. In contrast, between 2018 and 2020 we found change in psychological distress did not differ by employment loss. However, residents who had financial concerns and lost their jobs had the largest increases in psychological distress, while residents who did not have serious financial concerns-potentially due to public assistance-but experienced job loss had no increase in distress, a better outcome even than those that retained their jobs. Using partial identification, we find job loss during the pandemic decreased psychological distress for those without serious financial concerns. This has important policy implications for how high-risk persons within low-income communities are identified and supported, as well as what type of public assistance may help.


Assuntos
COVID-19 , Angústia Psicológica , Negro ou Afro-Americano/psicologia , Humanos , Pandemias , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
6.
Sleep ; 45(3)2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35018476

RESUMO

STUDY OBJECTIVES: African Americans have faced disproportionate socioeconomic and health consequences associated with the COVID-19 pandemic. The current study examines employment and its association with sleep quality during the initial months of the pandemic in a low-income, predominantly African American adult sample. METHODS: In the early months of COVID-19 (March to May 2020), we administered a survey to an ongoing, longitudinal cohort of older adults to assess the impact of COVID-related changes in employment on self-reported sleep quality (N = 460; 93.9% African American). Participants had prior sleep quality assessed in 2018 and a subset also had sleep quality assessed in 2013 and 2016. Primary analyses focused on the prevalence of poor sleep quality and changes in sleep quality between 2018 and 2020, according to employment status. Financial strain and prior income were assessed as moderators of the association between employment status and sleep quality. We plotted trend lines showing sleep quality from 2013 to 2020 in a subset (n = 339) with all four waves of sleep data available. RESULTS: All participants experienced increases in poor sleep quality between 2018 and 2020, with no statistical differences between the employment groups. However, we found some evidence of moderation by financial strain and income. The trend analysis demonstrated increases in poor sleep quality primarily between 2018 and 2020. CONCLUSIONS: Sleep quality worsened during the pandemic among low-income African American adults. Policies to support the financially vulnerable and marginalized populations could benefit sleep quality.


Assuntos
COVID-19 , Idoso , COVID-19/epidemiologia , Emprego , Humanos , Pandemias , Características de Residência , Qualidade do Sono
7.
Rev Sci Instrum ; 92(7): 073306, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34340440

RESUMO

A retarding potential energy analyzer was used to obtain temporally resolved ion energy distribution functions (IEDFs) of a flowing laboratory plasma. The plasma of time varying ion energy was generated at 1 and 20 kHz using a commercial gridded ion source and modulated using a wideband power amplifier. Three plasma energy modulation setpoints were tested, and their IEDFs were reconstructed. This method leverages high-speed, low-noise instrumentation to obtain fast collector current measurements at discrete retarding bias levels, recombining them in the time domain using two data fusion techniques. The first method is an empirical transfer function, which determines the linear ratio of complex coefficients in Fourier space. The second method, shadow manifold interpolation, reconstructs the IEDFs point-by-point by comparing input and output datasets in a multi-dimensional phase space. Reconstructed IEDFs from the two methods are presented and compared. The two analysis methods show very good agreement.

8.
J Med Chem ; 64(14): 10047-10058, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34213885

RESUMO

A series of nondeuterated and deuterated dipeptidyl aldehyde and masked aldehyde inhibitors that incorporate in their structure a conformationally constrained cyclohexane moiety was synthesized and found to potently inhibit severe acute respiratory syndrome coronavirus-2 3CL protease in biochemical and cell-based assays. Several of the inhibitors were also found to be nanomolar inhibitors of Middle East respiratory syndrome coronavirus 3CL protease. The corresponding latent aldehyde bisulfite adducts were found to be equipotent to the precursor aldehydes. High-resolution cocrystal structures confirmed the mechanism of action and illuminated the structural determinants involved in binding. The spatial disposition of the compounds disclosed herein provides an effective means of accessing new chemical space and optimizing pharmacological activity. The cellular permeability of the identified inhibitors and lack of cytotoxicity warrant their advancement as potential therapeutics for COVID-19.


Assuntos
Antivirais/farmacologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Cicloexanos/farmacologia , Desenho de Fármacos , Inibidores de Proteases/farmacologia , SARS-CoV-2/efeitos dos fármacos , Antivirais/síntese química , Antivirais/química , Proteases 3C de Coronavírus/metabolismo , Cicloexanos/síntese química , Cicloexanos/química , Humanos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Conformação Molecular , Inibidores de Proteases/síntese química , Inibidores de Proteases/química , SARS-CoV-2/enzimologia , Tratamento Farmacológico da COVID-19
9.
Am J Prev Med ; 61(5): 683-691, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34226093

RESUMO

INTRODUCTION: Despite the growing recognition of the importance of neighborhood conditions for cardiometabolic health, causal relationships have been difficult to establish owing to a reliance on cross-sectional designs and selection bias. This is the first natural experiment to examine the impact of neighborhood revitalization on cardiometabolic outcomes in residents from 2 predominantly African American neighborhoods, one of which has experienced significant revitalization (intervention), whereas the other has not (comparison). METHODS: The sample included 532 adults (95% African American, 80% female, mean age=58.9 years) from 2 sociodemographically similar, low-income neighborhoods in Pittsburgh, PA, with preintervention and postintervention measures (2016 and 2018) of BMI, diastolic and systolic blood pressure, HbA1c, and high-density lipoprotein cholesterol and covariates. Data were collected in 2016 and 2018 and analyzed in 2020. RESULTS: Difference-in-difference analyses showed significant improvement in high-density lipoprotein cholesterol in intervention residents relative to that in the comparison neighborhood (ß=3.88, 95% CI=0.47, 7.29). There was also a significant difference-in-difference estimate in diastolic blood pressure (ß=3.00, 95% CI=0.57, 5.43), with residents of the intervention neighborhood showing a greater increase in diastolic blood pressure than those in the comparison neighborhood. No statistically significant differences were found for other outcomes. CONCLUSIONS: Investing in disadvantaged neighborhoods has been suggested as a strategy to reduce health disparities. Using a natural experiment, findings suggest that improving neighborhood conditions may have a mixed impact on certain aspects of cardiometabolic health. Findings underscore the importance of examining the upstream causes of health disparities using rigorous designs and longer follow-up periods that provide more powerful tests of causality.


Assuntos
Doenças Cardiovasculares , Características de Residência , Adulto , Negro ou Afro-Americano , Doenças Cardiovasculares/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pobreza
10.
Public Health Rep ; 136(4): 457-465, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33789530

RESUMO

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic has disproportionately strained households experiencing poverty, particularly Black and Latino households. Food insecurity, which entails having limited or uncertain access to a sufficient quantity of nutritious food, is a key pandemic-related consequence. We examined how people enrolled in the Supplemental Nutrition Assistance Program (SNAP) have been affected by the pandemic, particularly Black participants and participants residing in food deserts. METHODS: Using survey data from a longitudinal cohort study of predominantly Black low-income adults aged ≥18 residing in urban food deserts in Pittsburgh, Pennsylvania, we examined changes in food insecurity and SNAP participation before COVID-19 (2018) and early in the COVID-19 pandemic (March-May 2020). We modeled changes in food insecurity from 2018 to 2020 via covariate-adjusted logistic regression. RESULTS: Food insecurity increased significantly among participants enrolled in SNAP and surveyed in both 2018 and 2020 (from 25.9% in 2018 to 46.9% in 2020; P < .001). Compared with cohort participants not enrolled in SNAP at both points, cohort participants enrolled in SNAP in 2018 and 2020 had the highest rates of using a food bank in 2020 (44.4%) and being newly food insecure in 2020 (28.9%) (ie, they were food insecure in 2020 but not in 2018). CONCLUSIONS: Food insecurity during the COVID-19 pandemic increased among low-income Black households enrolled in SNAP and residing in a food desert. Public health recovery efforts might focus on modifying SNAP to improve the food security of people experiencing poverty.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , COVID-19 , Assistência Alimentar/estatística & dados numéricos , Insegurança Alimentar , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pennsylvania , Pobreza , Inquéritos e Questionários
11.
Anal Chem ; 93(8): 4015-4022, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33587599

RESUMO

Life was originally assumed to utilize the l-amino acids only. Since 1980s, the d-amino acid-containing peptides (DAACPs) were detected in animals, often at extremely low levels with tremendous functional specificity. As the unguided proteomic algorithms based on peptide masses are oblivious to DAACPs, many more are believed to be hidden in organisms and novel methods to tackle DAACPs are sought. Linear ion mobility spectrometry (IMS) can distinguish and characterize the d/l-epimers but is restricted by poor orthogonality to MS as in other contexts. We now bring to this area the newer technique of differential IMS (FAIMS). The orthogonality of MS to high-resolution FAIMS exceeded that to linear IMS by 6×, the greatest factor found for biomolecules so far. Hence, FAIMS has achieved the 2.5× resolution of trapped IMS on average despite a lower resolving power, fully separating all 18 pairs of representative epimer species with masses of ∼400-5,000 Da and charge states of 1-6. A constant isomer resolution over these ranges allows projecting success for yet larger DAACPs.


Assuntos
Peptídeos , Proteômica , Aminoácidos , Animais , Espectrometria de Mobilidade Iônica , Espectrometria de Massas
12.
Am J Public Health ; 111(3): 494-497, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33476228

RESUMO

Objectives. To examine the impact of COVID-19 shutdowns on food insecurity among a predominantly African American cohort residing in low-income racially isolated neighborhoods.Methods. Residents of 2 low-income African American food desert neighborhoods in Pittsburgh, Pennsylvania, were surveyed from March 23 to May 22, 2020, drawing on a longitudinal cohort (n = 605) previously followed from 2011 to 2018. We examined longitudinal trends in food insecurity from 2011 to 2020 and compared them with national trends. We also assessed use of food assistance in our sample in 2018 versus 2020.Results. From 2018 to 2020, food insecurity increased from 20.7% to 36.9% (t = 7.63; P < .001) after steady declines since 2011. As a result of COVID-19, the United States has experienced a 60% increase in food insecurity, whereas this sample showed a nearly 80% increase, widening a preexisting disparity. Participation in the Supplemental Nutrition Assistance Program (52.2%) and food bank use (35.9%) did not change significantly during the early weeks of the pandemic.Conclusions. Longitudinal data highlight profound inequities that have been exacerbated by COVID-19. Existing policies appear inadequate to address the widening gap.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , COVID-19/epidemiologia , Insegurança Alimentar , Pobreza/estatística & dados numéricos , Humanos , Estudos Longitudinais , Pandemias , Pennsylvania/epidemiologia , Características de Residência/estatística & dados numéricos , Fatores de Risco , SARS-CoV-2 , Estados Unidos/epidemiologia
13.
Prev Med ; 143: 106362, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33388325

RESUMO

The COVID-19 pandemic has caused financial stress and disrupted daily life more quickly than any prior economic downturn and on a scale beyond any prior natural disaster. This study aimed to assess the impact of the pandemic on psychological distress and identify vulnerable groups using longitudinal data to account for pre-pandemic mental health status. Clinically significant psychological distress was assessed with the Kessler-6 in a national probability sample of adults in the United States at two time points, February 2019 (T1) and May 2020 (T2). To identify increases in distress, psychological distress during the worst month of the past year at T1 was compared with psychological distress over the past 30-days at T2. Survey adjusted logistic regression was used to estimate associations of demographic characteristics at T1 (gender, age, race, and income) and census region at T2 with within-person increases in psychological distress. The past-month prevalence of serious psychological distress at T2 was as high as the past-year prevalence at T1 (10.9% vs. 10.2%). Psychological distress was strongly associated across assessments (X2(4) = 174.6, p < .0001). Increase in psychological distress above T1 was associated with gender, age, household income, and census region. Equal numbers of people experienced serious psychological distress in 30-days during the pandemic as did over an entire year prior to the pandemic. Mental health services and research efforts should be targeted to those with a history of mental health conditions and groups identified as at high risk for increases in distress above pre-pandemic levels.


Assuntos
COVID-19/epidemiologia , COVID-19/psicologia , Transtornos Mentais/epidemiologia , Pandemias/estatística & dados numéricos , Angústia Psicológica , Estresse Psicológico/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Inquéritos e Questionários , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
14.
J Rural Health ; 37(1): 45-54, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32022951

RESUMO

PURPOSE: Rural-urban disparities in the surgical and anesthesia workforce exist. This mixed-methods study describes the distribution of the surgical and anesthesia workforce and qualitatively explores how such workforce and other factors influence rural hospitals' provision of surgical services. METHODS: We calculated provider counts by county from the Area Health Resource File. Using American Hospital Association survey data, we sampled rural hospitals, stratified by critical access status and state policies. We conducted qualitative semistructured interviews with administrators at 16 hospitals and performed directed content analysis of factors influencing surgical services provision at rural hospitals. FINDINGS: Within rural counties, 55.1% of counties had no surgeon, 81.2% had no anesthesiologist, and 58.1% had no Certified Registered Nurse Anesthetist (CRNA). Administrators reported that rural hospitals struggled to provide many surgical services given lack of subspecialty surgeons and adequate postsurgical care. Rural hospitals likely struggle to generate volumes necessary to support safe and profitable subspecialty surgery programs. Anesthesia services were not reported as a current limitation given that CRNAs in particular had strong, diverse skills sets and many hospitals allowed high CRNA autonomy. However, meeting anesthesia needs for emergency surgeries and 24-hour obstetrics posed significant challenges. CONCLUSIONS: While rural hospitals reported meeting community needs for elective and noncomplex surgeries, rural hospitals continued to face significant challenges providing subspecialty surgeries, emergency surgeries, and 24-hour obstetrical services.


Assuntos
Anestesia , Serviços de Saúde Rural , Feminino , Hospitais Rurais , Humanos , Enfermeiros Anestesistas , Gravidez , População Rural , Estados Unidos , Recursos Humanos
15.
Am J Epidemiol ; 190(5): 798-806, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33047782

RESUMO

Neighborhood socioeconomic conditions (NSECs) are associated with resident diet, but most research has been cross-sectional. We capitalized on a natural experiment in Pittsburgh, Pennsylvania, in which 1 neighborhood experienced substantial investments and a sociodemographically similar neighborhood that did not, to examine pathways from neighborhood investments to changed NSECs and changed dietary behavior. We examined differences between renters and homeowners. Data were from a random sample of households (n = 831) in each of these low-income Pittsburgh neighborhoods that were surveyed in 2011 and 2014. Structural equation modeling tested direct and indirect pathways from neighborhood to resident dietary quality, adjusting for individual-level sociodemographics, with multigroup testing by homeowners versus renters. Neighborhood investments were directly associated with improved dietary quality for renters (ß = 0.27, 95% confidence interval (CI): 0.05, 0.50) and homeowners (ß = 0.51, 95% CI: 0.10, 0.92). Among renters, investments also were associated with dietary quality through a positive association with commercial prices (ß = 0.34, 95% CI: 0.15, 0.54) and a negative association with residential prices (ß = -0.30, 95% CI: -0.59, -0.004). Among homeowners, we did not observe any indirect pathways from investments to dietary quality through tested mediators. Investing in neighborhoods may support resident diet through improvements in neighborhood commercial environments for renters, but mechanisms appear to differ for homeowners.


Assuntos
Negro ou Afro-Americano , Dieta Saudável/etnologia , Propriedade , Características de Residência , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Insegurança Alimentar , Humanos , Masculino , Rememoração Mental , Pessoa de Meia-Idade , Modelos Estatísticos , Pennsylvania , Áreas de Pobreza , Fatores Socioeconômicos
16.
J Am Soc Mass Spectrom ; 32(1): 340-345, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33201698

RESUMO

Mass spectrometry (MS) and isotopes were intertwined for a century, with stable isotopes central to many MS identification and quantification protocols. In contrast, the analytical separations including ion mobility spectrometry (IMS) largely ignored isotopes, partly because of insufficient resolution. We recently delineated various halogenated aniline isomers by structurally specific splitting in FAIMS spectra. While this capability hinges on the 13C shifts, all preceding studies leveraged 37Cl or 81Br to enhance the differentiation. However, such abundant heavy isotopes are absent from typical organic compounds. With single I isotope, iodinated organics generate similar isotopic envelopes dominated by the 13C atoms. Here, we distinguish the three monoiodoaniline isomers based on the shifts solely for one or two 13C atoms. The differentiation may be somewhat improved using multipoint peak position descriptions for more reproducible shifts. The interisomer order of shifts differs from those for chlorinated or brominated analogues, showcasing the specificity of approach. We also investigated the mass scaling of isotopic shifts, encountering divergent trends for different structural families.

17.
Hous Policy Debate ; 30(2): 164-190, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013148

RESUMO

During the 1990s, the U.S. Department of Housing and Urban Development awarded more than $6 billion in competitive grants called HOPE VI to spur neighborhood redevelopment. We add to HOPE VI research by examining the impacts of a large set of public-private real estate investments, including HOPE VI, made over a 16-year period in a distressed Pittsburgh neighborhood called the Hill District. Specifically, we estimate the effects of the $468 million additional public-private investments that Hill District received compared to a demographically similar neighborhood on sale prices, rental prices, and crime. We find large and statistically significant impacts of the public-private investments on residential sales prices, commercial sales prices, and on rental prices, but only a marginally significant yet meaningful decline in non-violent arrests. For each additional $10 million of public-private investment, we find a 0.95 percent increase in residential sales prices, 2.7 percent increase in commercial sales prices, and 0.55 percent increase in rental prices. Because there was an accumulated difference over 16 years of $468 million in the amount of public-private investment across the two neighborhoods we examine, these percentage increases amount to large changes in real estate prices over that time. Commercial real estate investors and homeowners benefited the most, followed by residential landlords. Our analyses imply cities should anticipate the potential impacts of major neighborhood investment on low-income households, especially unsubsidized renters that most directly experience the brunt of rising rents.

18.
J Am Soc Mass Spectrom ; 31(1): 137-145, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-32881519

RESUMO

The isotopic molecular envelopes due to stable isotopes for most elements were a staple of mass spectrometry since its origins, often leveraged to identify and quantify compounds. However, all isomers share one MS envelope. As the molecular motion in media also depends on the isotopic composition, separations such as liquid chromatography (LC) and ion mobility spectrometry (IMS) must also feature isotopic envelopes. These were largely not observed because of limited resolution, except for the (structurally uninformative) shifts in LC upon H/D exchange. We recently found the isotopic shifts in FAIMS for small haloanilines (∼130-170 Da) to hinge on the halogen position, opening a novel route to isomer characterization. Here, we extend the capability to heavier species: dibromoanilines (DBAs, ∼250 Da) and tribromoanilines (TBAs, ∼330 Da). The 13C shifts for DBAs and TBAs vary across isomers, some changing sign. While 81Br shifts are less specific, the 2-D 13C/81Br shifts unequivocally differentiate all isomers. The trends for DBAs track those for dichloroanilines, with the 13C shift order preserved for most isomers. The peak broadening due to merged isotopomers is also isomer-specific. The absolute shifts for TBAs are smaller than those for lighter haloanilines, but differentiate isomers as well because of compressed uncertainties. These results showcase the feasibility of broadly distinguishing isomers in the more topical ∼200-300 Da range using the isotopic shifts in IMS spectra.

19.
Health Place ; 64: 102361, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32838886

RESUMO

This study examined the effect of neighborhood investments on neighborhood walkability, presence of incivilities, and crime in two low-income, primarily African American neighborhoods in Pittsburgh, USA. During the study period, one of the neighborhoods (the intervention neighborhood) received substantially more publicly-funded investments than a demographically matched comparison neighborhood. Comparisons between the neighborhoods showed a significant difference-in-difference for all three outcomes. The intervention neighborhood experienced significantly more change related to improved walkability and decreased incivilities. However, the control neighborhood experienced better crime-related outcomes. Analyses that focused on resident proximity to investments found similar results. This highlights the nuances of neighborhood investment, which is important to consider when thinking about public policy.


Assuntos
Características de Residência , Caminhada , Negro ou Afro-Americano , Crime , Humanos , Pobreza
20.
J Am Soc Mass Spectrom ; 31(7): 1603-1609, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32501708

RESUMO

Glycosylation is a ubiquitous post-translational modification (PTM) that strongly affects the protein folding and function. Glycosylation patterns are impacted by many diseases, making promising biomarkers. Glycans are also the most complex PTMs, exhibiting isomers (linkage, anomers, and those with isomeric moieties). Permuted with localization variants that occur for all PTMs, these produce numerous isomeric glycoforms. Characterizing them by mass spectrometry and ion mobility spectrometry (IMS) has been a challenge. High-definition differential IMS (FAIMS) had robustly disentangled isomeric peptides involving other PTMs but was not evaluated for glycopeptides that featured multilevel isomerism. Here, we apply it to representative mucin glycopeptides with O-linked glycans: three GalNAc localization variants, a pair with α/ß GalNAc anomers, and another with GalNAc/GlcNAc isomers. The first two classes were separated baseline with the resolution exceeding previous benchmarks by 10-fold, and the last pair was partly resolved. The recently demonstrated straightforward coupling to ultrahigh-resolution MS and electron-transfer dissociation makes high-definition FAIMS an attractive tool for glycoproteomics.


Assuntos
Glicopeptídeos/análise , Espectrometria de Mobilidade Iônica/métodos , Espectrometria de Massas/métodos , Polissacarídeos/análise , Glicopeptídeos/química , Glicosilação , Isomerismo , Polissacarídeos/química , Processamento de Proteína Pós-Traducional
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