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1.
Clin Chem ; 70(7): 948-956, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38965696

ABSTRACT

BACKGROUND: Maternal serum alpha-fetoprotein (AFP) levels are used in screening for open neural tube defects (ONTD). Historical reports show that AFP levels and maternal weights are higher in self-reported Black than White individuals, but recent reports question the need to account for these variables in screening. Our study compares screening performance with and without accounting for race. METHODS: Retrospective analysis was performed on deidentified prenatal screening records including maternal weight and self-reported race of White or Black. Gestational age-specific medians and weight-adjusted multiples of the median levels were calculated separately for each group and using a race-agnostic analysis. Outcome measures included the proportion of screen-positive results. RESULTS: Records for analysis (n = 13 316) had an ultrasound confirmed gestational age between 15 and 21 completed weeks, singleton pregnancy, and self-reported race. Race was Black for 26.3%. AFP levels for pregnancies in Black individuals were higher than in White individuals: 6% to 11% depending on gestational age. Race-specific gestational age and maternal weight analyses resulted in similar screen-positive rates for self-reported White and Black individuals at 0.74% vs 1.00%, respectively (P = 0.14). However, use of race-agnostic analyses resulted in a screen-positive rate that was 2.4 times higher in Black than White individuals (P < 0.001). CONCLUSION: These data show that the historical method of accounting for maternal race and weight in prenatal screening for ONTD provides equitable performance. Using a race-agnostic methodology results in an increased screen-positive rate and a disproportionate rate of required follow-up care for individuals who self-identify as Black.


Subject(s)
Neural Tube Defects , White People , alpha-Fetoproteins , Humans , Female , Neural Tube Defects/diagnosis , Neural Tube Defects/blood , Pregnancy , alpha-Fetoproteins/analysis , Retrospective Studies , Adult , Body Weight , Gestational Age , Prenatal Diagnosis/methods
2.
PLoS One ; 18(3): e0270341, 2023.
Article in English | MEDLINE | ID: mdl-36920940

ABSTRACT

We examine the determinants of the consequences of COVID-19 on employment and wages in the United States. Guided by a pre-analysis plan, we investigate whether the economic consequences of COVID-19 were larger for certain occupations, using four indexes: workers relatively more exposed to disease, workers that work with proximity to coworkers, essential/critical workers and workers who can easily work remotely. We find that individuals that work in proximity to others are more affected while individuals able to work remotely and essential workers are less affected by the pandemic. We also present suggestive evidence that our indexes are likely explanations why certain demographic groups such as younger and minority workers have worse labor market outcomes during the pandemic.


Subject(s)
COVID-19 , United States/epidemiology , Humans , COVID-19/epidemiology , Employment , Occupations , Salaries and Fringe Benefits , Minority Groups
3.
ACS Appl Mater Interfaces ; 14(1): 49-56, 2022 Jan 12.
Article in English | MEDLINE | ID: mdl-34978405

ABSTRACT

The development of low-cost, non-toxic, scalable antimicrobial textiles is needed to address the spread of deadly pathogens. Here, we report a polysiloxane textile coating that possesses two modes of antimicrobial inactivation, passive contact inactivation through amine/imine functionalities and active photodynamic inactivation through the generation of reactive oxygen species (ROS). This material can be coated and cross-linked onto natural and synthetic textiles through a simple soak procedure, followed by UV cure to afford materials exhibiting no aqueous leaching and only minimal leaching in organic solvents. This coating minimally impacts the mechanical properties of the fabric while also imparting hydrophobicity. Passive inactivation of Escherichia coli (E. coli) and methicillin-resistant Staphylococcus aureus (MRSA) is achieved with >98% inactivation after 24 h, with a 23× and 3× inactivation rate increase against E. coli and MRSA, respectively, when green light is used to generate ROS. Up to 90% decrease in the infectivity of SARS-CoV-2 after 2 h of irradiated incubation with the material is demonstrated. These results show that modifying textiles with dual-functional polymers results in robust and highly antimicrobial materials that are expected to find widespread use in combating the spread of deadly pathogens.


Subject(s)
Anti-Infective Agents/pharmacology , Bacteria/drug effects , Coated Materials, Biocompatible/chemistry , Polymers/chemistry , SARS-CoV-2/drug effects , Textiles/analysis , Anti-Infective Agents/chemistry , COVID-19/prevention & control , COVID-19/virology , Coated Materials, Biocompatible/pharmacology , Escherichia coli/drug effects , Humans , Methicillin-Resistant Staphylococcus aureus/drug effects , Photochemotherapy/methods , Reactive Oxygen Species/metabolism , SARS-CoV-2/isolation & purification , Textiles/toxicity , Ultraviolet Rays
4.
Can J Econ ; 55(Suppl 1): 214-247, 2022 Feb.
Article in English | MEDLINE | ID: mdl-38607895

ABSTRACT

In this paper, we study the effect of COVID-19 on the labour market and reported mental health of Canadians. To better understand the effect of the pandemic on the labour market, we build indexes for whether workers: (i) are relatively more exposed to disease, (ii) work in proximity to co-workers, (iii) are essential workers and (iv) can easily work remotely. Our estimates suggest that the impact of COVID-19 was significantly more severe for workers that work in proximity to co-workers and those more exposed to disease who are not in the health sector, while the effects are less severe for essential workers and workers that can work remotely. Last, using the Canadian Perspective Survey Series, we observe that reported mental health is significantly lower among some of the most affected workers such as women and less-educated workers. We also document that those who were absent from work because of COVID-19 are more concerned with meeting their financial obligations and with losing their job than those who continue working outside their home.


Conséquences économiques de la COVID­19 à court terme : tâches professionnelles et santé mentale au Canada. Dans cet article, nous étudions les répercussions de la COVID­19 sur le marché de l'emploi et la santé mentale déclarée des Canadiens. Afin de mieux comprendre les effets de la pandémie sur le marché du travail, nous avons développé des indices permettant de déterminer si les travailleurs : 1) sont relativement plus exposés à la maladie; 2) exercent leur activité à proximité de leurs collègues; 3) sont essentiels; 4) peuvent facilement travailler à distance. D'après nos estimations, les conséquences de la COVID­19 se sont avérées nettement plus sévères chez les travailleurs exerçant à proximité de leurs collègues ainsi que les professionnels (hors secteur médical) davantage exposés à la maladie, mais moins importantes chez les travailleurs essentiels et les télétravailleurs. Enfin, en nous appuyant sur l'une des enquêtes sur les perspectives canadiennes, nous observons que la santé mentale déclarée est nettement inférieure chez les travailleurs les plus touchés, notamment les femmes et les travailleurs moins instruits. Nous montrons également que les personnes écartées de leur travail en raison de la COVID­19 se soucient davantage du respect de leurs obligations financières et de la perte de leur emploi par rapport à celles qui ont pu continuer à travailler hors de leur domicile.

5.
6.
ACS Appl Mater Interfaces ; 13(19): 22195-22203, 2021 May 19.
Article in English | MEDLINE | ID: mdl-33944560

ABSTRACT

Mechanically robust bulk antimicrobial polymers are one way to address disease transmission via contaminated surfaces. Here, we demonstrate the visible light photo-oxidative cross-linking of amine-containing PDMS using a single-component, solvent-free system where amines have a dual role as antimicrobial functionalities and cross-linking sites. Rose Bengal, a xanthene dye used as a fluorescent stain, is thermally reacted with the polymer to give a solvent-free liquid siloxane that can generate reactive singlet oxygen upon aerobic green light irradiation, coupling the amine functionalities into imine cross-links. Photorheological experiments demonstrate that light intensity is the largest kinetic factor in the photo-oxidative curing of these polymers. Room temperature irradiation under an ambient atmosphere results in free-standing elastic materials with mechanical properties that depend on the amount of Rose Bengal present. An ultimate elongation strain of 117% and Young's modulus of 2.15 MPa were observed for the highest dye loading, with both mechanical properties found to be higher than those for the same solution-based dye amounts. We demonstrate that the solvent-free nature of the material can be exploited to generate 3D structures using low-temperature deposition as well as direct-write patterning and photolithography on glass substrates. The antimicrobial activity was investigated, with the cross-linked material demonstrating greater efficacy against E. coli (Gram negative) compared with MRSA (Gram positive) bacterial strains and inducing complete cell lysis of incubated CHO-K1 mammalian cells, demonstrating applicability as a mechanically robust single-component antimicrobial elastomer.


Subject(s)
Anti-Bacterial Agents/chemistry , Elastomers/chemistry , Photochemical Processes , Siloxanes/chemistry , Anti-Bacterial Agents/pharmacology , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Microbial Sensitivity Tests , Spectrum Analysis/methods
7.
Science ; 371(6535): 1278, 2021 Mar 19.
Article in English | MEDLINE | ID: mdl-33737491
8.
J Environ Econ Manage ; 106: 102427, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33583969

ABSTRACT

This paper investigates the impacts of COVID-19 safer-at-home polices on collisions and pollution. We find that statewide safer-at-home policies lead to a 20% reduction in vehicular collisions and that the effect is entirely driven by less severe collisions. For pollution, we find particulate matter concentration levels approximately 1.5 µg/m3 lower during the period of a safer-at-home order, representing a 25% reduction. We document a similar reduction in air pollution following the implementation of similar policies in Europe. We calculate that as of the end of June 2020, the benefits from avoided car collisions in the U.S. were approximately $16 billion while the benefits from reduced air pollution could be as high as $13 billion.

9.
Chem Sci ; 11(11): 3081-3088, 2020 Feb 28.
Article in English | MEDLINE | ID: mdl-34122813

ABSTRACT

Bulk crystallization in flexible polymeric systems is difficult to control due to the random orientation of the chains. Here we report a photo cross-linking strategy that results in simultaneous cross-linking and crystallization of polysiloxane chains into millimeter sized leaf-like polycrystalline structures. Polymers containing pendant anthracene groups are prepared and undergo [4+4] photocycloaddition under 365 nm irradiation at room temperature. The growth and morphology of the crystalline structures is studied using polarized optical microscopy (POM) and atomic force microscopy and is found to progress through three unique stages of nucleation, growth, and constriction. The mobility of the individual chains is probed using pulsed-field gradient (PFG) NMR to provide insights into the diffusion processes that may govern chain transport to the growing crystal fronts. The room temperature crystallization of this conventionally amorphous polymer system may allow for a new level of morphological control for silicone materials.

12.
Chemistry ; 22(32): 11303-9, 2016 Aug 01.
Article in English | MEDLINE | ID: mdl-27359247

ABSTRACT

Ba5 Fe6+x S4+x O8 was synthesized through a solid-state reaction, and pure powders of nominal compositions x=0.44-0.55 were obtained after being rinsed with water. The crystal structures (P4/mmm, a=10.13, c=4.03 Å) and sample purities were investigated by powder synchrotron X-ray diffraction and were found to be composed of a tunnel lattice (Ba5 Fe6 S4 O8 ), built from fused perovskite units and the tunnel filling (Fex Sx ). The variable composition, that is, the tunnel filling (x), causes partially occupied sites as well as crystallographic split positions. Ba5 Fe6+x S4+x O8 (x=0.525) is semiconducting and all investigated compositions exhibit magnetic ground states that could be described as either semi-spin-glass-like (x>0.5) or canted antiferromagnetic (x<0.5). The spin-glass in x=0.525 exhibits magnetic relaxations that are affected by ageing.

13.
Angew Chem Int Ed Engl ; 55(32): 9380-3, 2016 08 01.
Article in English | MEDLINE | ID: mdl-27309149

ABSTRACT

Small, red Fe2 SeO single crystals in two modifications were obtained from a CsCl flux. The metastable α-phase is pseudo-tetragonal (Cmce, a=16.4492(8) Å, b=11.1392(4) Å, c=11.1392(4) Å), whereas the ß-phase is trigonal (P31 , a=9.8349(4) Å, c=6.9591(4) Å)) and thermodynamically stable within a narrow temperature range. Both crystal structures were solved from twinned specimens. The enantiomers of the ß-phase appear as racemic mixtures. Selenium and oxygen form two individual interpenetrating primitive cubic lattices, giving a bcc packing. A quasi-octahedrally coordinated iron atom is found close to the center of each surface of the selenium sublattice. The difference between the α- and ß-phases is the distribution of iron at 2/3 of the surfaces. α- and ß-Fe2 SeO are comparable with metal-vacancy-ordered antiperovskites. Each Fe/O lattice can also be described in terms of vertex-sharing OFe4 tetrahedra, with a crystal structure similar to that of an antisilicate. Iron is divalent and has a high-spin d(6) (S=2) configuration. The ß-phase exhibits magnetoelectric coupling.

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