Background: Research has consistently shown that there is no safe blood lead level (BLL) for children. Despite progress in lead poisoning prevention, lead exposure remains a persistent threat to the health and neurological development of children. To identify high-risk ZIP codes for use by families and health care providers for the entire state of North Carolina, we developed a risk model using ZIP Code Tabula-tion Area (ZCTA)-level census data.
View Article and Find Full Text PDFObjectives: To assess the economic and mental health impacts of COVID-19 in the presence of previous exposure to flooding events.
Methods: Starting in April 2018, the Texas Flood Registry (TFR) invited residents to complete an online survey regarding their experiences with Hurricane Harvey and subsequent flooding events. Starting in April 2020, participants nationwide were invited to complete a brief online survey on their experiences during the pandemic.
The presence of arsenic in groundwater and other drinking water sources presents a notable public health concern. Although the utilization of iron oxide nanomaterials as arsenic adsorbents has shown promising results in batch experiments, few have succeeded in using nanomaterials in filter setups. In this study, the performance of nanomaterials, supported on sand, was first compared for arsenic adsorption by conducting continuous flow experiments.
View Article and Find Full Text PDFCOVID-19 remains a global threat in the face of emerging SARS-CoV-2 variants and gaps in vaccine administration and availability. In this study, we analyze a data-driven COVID-19 testing program implemented at a mid-sized university, which utilized two simple, diverse, and easily interpretable machine learning models to predict which students were at elevated risk and should be tested. The program produced a positivity rate of 0.
View Article and Find Full Text PDFImportance: The COVID-19 pandemic led many higher education institutions to close campuses during the 2020-2021 academic year. As campuses prepared for a return to in-person education, many institutions were mandating vaccines for students and considering the same for faculty and staff.
Objective: To determine the association between vaccination coverage and the levels and spread of SARS-CoV-2, even in the presence of highly-transmissible variants and congregate living, at a midsized university in the US.
Millions of people a year receive magnetic resonance imaging (MRI) contrast agents for the diagnosis of conditions as diverse as fatty liver disease and cancer. Gadolinium chelates, which provide preferred T contrast, are the current standard but face an uncertain future due to increasing concerns about their nephrogenic toxicity as well as poor performance in high-field MRI scanners. Gadolinium-containing nanocrystals are interesting alternatives as they bypass the kidneys and can offer the possibility of both intracellular accumulation and active targeting.
View Article and Find Full Text PDFThe syntheses, structures, and magnetic properties of four new complex salts, (PPN){[Mn(III)(salphen)(MeOH)]2[M(III)(CN)6]}·7MeOH (Mn2M·7MeOH) (M = Fe, Ru, Os and Co; PPN(+) = bis(triphenylphosphoranylidene)ammonium cation; H2salphen = N,N'-bis(salicylidene)-1,2-diaminobenzene), and a mixed metal Co/Os analogue (PPN){[Mn(III)(salphen)(MeOH)]2[Co(III)0.92Os(III)0.08(CN)6]}·7MeOH were undertaken.
View Article and Find Full Text PDFMany of the solution phase properties of nanoparticles, such as their colloidal stability and hydrodynamic diameter, are governed by the number of stabilizing groups bound to the particle surface (i.e., grafting density).
View Article and Find Full Text PDFThe study of paramagnetic compounds based on 4d and 5d transition metals is an emerging research topic in the field of molecular magnetism. An essential driving force for the interest in this area is the fact that heavier metal ions introduce important attributes to the physical properties of paramagnetic compounds. Among the attractive characteristics of heavier elements vis-à-vis magnetism are the diffuse nature of their d orbitals, their strong magnetic anisotropy owing to enhanced spin-orbit coupling, and their diverse structural and redox properties.
View Article and Find Full Text PDFTo expand the field of new cyanide materials of the 5d elements, we incorporated the [Os(CN)(6)](3-) anion into PB architectures in combination with the Co(II) cation. Herein, we report the first example of a photomagnetic PB analog containing Os(III) ions. In a similar vein as the prototypical CoFe PB analogs, this compound exhibits a wide variety of properties including Charge Transfer Induced Spin Transition (CTIST), Temperature Induced Excited Spin State Trapping (TIESST), and magnetic ordering.
View Article and Find Full Text PDFDerivatives of the single molecule magnet (SMM) {[Re(triphos)(CN)(3)](4)[MnCl](4)} (Re(4)Mn(4)) {[Re(triphos)(CN)(3)](4)[Mn(CH(3)CN)](4)}(ClO(4))(4) (2) and {[Re(triphos)(CN)(3)](4)[Mn(ClO(4))](3)[Mn(CH(3)OH)(CH(3)O)]} (3), were prepared by reacting [Et(4)N][Re(triphos)(CN)(3)] (1) with Mn(ClO(4))(2)·6H(2)O. Reaction of sodium dicyanamide, NaN(CN)(2), with compound 2 in CH(2)Cl(2) results in the product {[Re(triphos)(CN)(3)](4)[Mn(N(CN)(2))](4)} (4), in which each Mn(II) site is terminated by a dicyanamide ligand. A similar reaction of compound 3 in CH(2)Cl(2)-MeOH solution with LiTCNQ (TCNQ = 7,7,8,8-tetracyanoquinodimethane) leads to the formation of {[Re(triphos)(CN)(3)](4)[Mn(TCNQ-TCNQ)(3)(Mn(HTCNQ)(CH(3)O))]} (5) whose structure is best described as a chain of dimers of Re(4)Mn(4) cubes bridged by sigma-bonded (TCNQ(2))(2-) linkers with one capping HTCNQ ligand.
View Article and Find Full Text PDFReactions between the [M(III)(CN)(6)](3-) (M = Fe and Co) anions and the mononuclear complex [Co(II)(dppe)(2)(H(2)O)][BF(4)](2) result in the formation of two isostructural trinuclear clusters {[Co(II)(dppe)(2)](2)[M(III)(CN)(6)]}(BF(4)). Surprisingly, reactions of [Co(dppe)(2)(H(2)O)](BF(4))(2) and [Co(triphos)(CH(3)CN)(2)](BF(4))(2) with [Cr(CN)(6)](3-) yield the mononuclear complexes [Co(dppe)(2)(CN)](BF(4)) and [Co(triphos)(CN)(2)], respectively. In the former case, an unusual pentanuclear intermediate complex {[Co(II)(3)(dppe)(4)(MeCN)][Cr(III)(CN)(6)](2)} was isolated.
View Article and Find Full Text PDFA series of structurally related pseudocubic metal cyanide clusters of Re(II) and 3d metal ions [{MX}4{Re(triphos)(CN)3}4] (M = Mn, Fe, Co, Ni, Zn; X = Cl, I, -OCH3) have been prepared, and their magnetic and electrochemical properties have been probed to evaluate the effect of changing the identity of the 3d metal ion. Electrochemistry of the clusters reveals several rhenium-based oxidation and reduction processes, some of which result in cluster fragmentation. The richest electrochemistry was observed for the iron congener, which exists as the Re(I)/Fe(III) cluster at the resting potential and exhibits six clear one-electron reversible redox couples and two, closely spaced one-electron quasi-reversible processes.
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