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Transition-metal dichalcogenides (TMDCs), including MoS2, have great potential in electronics applications. However, achieving low-resistance metal contacts is a challenge that impacts their performance in nanodevices due to strong Fermi-level pinning and the presence of a tunnelling barrier. As a solution, we explore a strategy of inserting monolayers of alkaline-earth sub-pnictide electrenes with a general formula of [M2X]+e- (M = Ca, Sr, Ba; X = N, P, As, Sb) between the TMDC and the metal. These electrenes possess two-dimensional sheets of charge on their surfaces that can be readily donated when interfaced with a TMDC semiconductor, thereby lowering its conduction band below the Fermi level and eliminating the Schottky and tunnelling barriers. In this work, density-functional theory (DFT) calculations were performed for metal/electrene/MoS2 heterojunctions for all stable M2X electrenes and both Au and Cu metals. To identify the material combinations that provide the most effective Ohmic contact, the charge transfer, band structure, and electrostatic potential were computed. Linear correlations were found between the charge donated to the MoS2 and both the electrene surface charge and work function. Overall, Ca2N appears to be the most promising electrene for achieving an Ohmic metal/MoS2 contact due to its high surface charge density.
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Metalloporphyrins are widely used as homogeneous electrocatalysts for transformations relevant to clean energy and sustainable organic synthesis. Metalloporphyrins are well-known to aggregate due to π-π stacking, but surprisingly, the influence of aggregation on homogeneous electrocatalytic performance has not been investigated previously. Herein, we present three structurally related iron meso-phenylporphyrins whose aggregation properties are different in commonly used N,N-dimethylformamide (DMF) electrolyte. Both spectroscopy and light scattering provide evidence of extensive porphyrin aggregation under conventional electrocatalytic conditions. Using the electrocatalytic reduction of CO2 to CO as a test reaction, cyclic voltammetry reveals an inverse dependence of the kinetics on the catalyst concentration. The inhibition extends to bulk performance, where up to 75% of the catalyst at 1 mM is inactive compared to at 0.25 mM. We additionally report how aggregation is perturbed by organic additives, axial ligands, and redox state. Periodic boundary calculations provide additional insights into aggregate stability as a function of metalloporphyrin structure. Finally, we generalize the aggregation phenomenon by surveying metalloporphyrins with different metals and substituents. This study demonstrates that homogeneous metalloporphyrins can aggregate severely in well-solubilizing organic electrolytes, that aggregation can be easily modulated through experimental conditions, and that the extent of aggregation must be considered for accurate catalytic benchmarking.
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Background: In lower-and middle-income countries (LMICs), studies of interventions to reduce intimate partner violence (IPV) perpetration are expanding yet measurement equivalence of the construct has not been established. We assessed the measurement equivalence of physical and sexual IPV perpetration used in recent trials in LMICs and tested the impact of non-invariance on trial inference. Methods: With data from three recent intervention trials among men (sample size 505-1537 across studies), we calculated tetrachoric correlations among items and used multiple-group confirmatory factor analysis to assess invariance across arms and over time. We also assessed treatment effects adjusting for covariate imbalance and using inverse probability to treatment weights to assess concordance of invariant measures with published results, where warranted. Findings: The average correlation among items was high and increased over time with several items in two studies showing correlations ≥0.85 at endline. Increases in correlation for physical IPV were concentrated in the treatment arm in two of the studies. The increase in correlation in sexual IPV differed by arm across studies. Across all studies, a correlated two-factor solution was the best fitting model according to the EFAs and CFAs. One study demonstrated measurement invariance across arms and over time. In two of the studies, longitudinal measurement non-invariance was detected in the intervention arms. In post hoc testing, one study attained invariance with a one-factor model and study inference was concordant with published findings. The other study did not attain even partial invariance. Conclusion: Common measures of physical and sexual IPV perpetration cannot be used for valid effect estimation without further refinement. The study highlights the need for an expanded item set, content validity assessments, further measurement invariance testing, and then consistent use of the item sets in future intervention trials to support accurate inference on the effectiveness of IPV perpetration prevention interventions.
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Background: In lower-and middle-income countries (LMICs), studies of interventions to reduce intimate partner violence (IPV) perpetration are expanding, yet measurement equivalence of the IPV perpetration construct that is the primary outcome in these investigations has not been established. We assessed the measurement equivalence of physical and sexual IPV perpetration item sets used in recent trials in LMICs and tested the impact of non-invariance on trial inference. Methods: With data from three intervention trials among men (sample size 505-1537 across studies) completed in 2019, we calculated tetrachoric correlations among items and used multiple-group confirmatory factor analysis to assess invariance across arms and over time. We also assessed treatment effects adjusting for covariate imbalance and using inverse probability to treatment weights to assess concordance of invariant measures with published results, where warranted. Findings: The average correlation among items measuring IPV perpetration was high and increased by 0.03 to 0.15 for physical IPV and 0.07 to 0.17 for sexual IPV over time with several items in two studies showing correlations ≥ 0.85 at endline. Increases in the degree of correlation for physical IPV were concentrated in the treatment arm in two of the studies. The increase in correlation in sexual IPV differed by arm across studies. Across all studies, a correlated two-factor solution was the best fitting model according to the EFAs and CFAs. One study demonstrated measurement invariance across arms and over time. In two of the studies, longitudinal measurement non-invariance was detected in the intervention arms. In post hoc testing, one study attained invariance with a one-factor model and study inference was concordant with published findings. The other study did not attain even partial invariance. Conclusion: Common measures of physical and sexual IPV perpetration cannot be used validly for comparisons across treatment versus control groups over time without further refinement. The study highlights the need for an expanded item set, content validity assessments, further measurement invariance testing, and then consistent use of the item sets in future intervention trials to ensure valid inferences regarding the effectiveness of IPV perpetration prevention interventions within and across trials.
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BACKGROUND: Nutrition-Focused Physical Exam (NFPE) feasibility is not well-studied. We describe registered dietitian nutritionist (RDN)-reported NFPE completion for hospitalized adult and pediatric patients overall and by assessment parameters. METHODS: Trained RDNs systematically conducted NFPEs for hospitalized adult and pediatric patients during the Academy of Nutrition and Dietetics and American Society for Parenteral and Enteral Nutrition Indicators to diagnose Malnutrition multisite cohort study (ClinicalTrials.gov: NCT03928548). RDNs reported their ability to evaluate assessment sites for subcutaneous fat and muscle loss, fluid accumulation, and micronutrient status and to complete handgrip strength (adults and children ≥6 years) and mid-upper arm circumference measurements (children). RDNs noted if they could complete the full NFPE; if not, they noted challenges. We descriptively summarized results and used multilevel logistic regression models to examine relationships between patient characteristics and NFPE completion. RESULTS: RDNs from 39 adult and 29 pediatric US hospitals conducted NFPEs for 327 adults and 214 children aged 1 month to 17.9 years. RDNs reported completing the examination for 44% (n = 145) of adults and 15% (n = 33) of children. They successfully evaluated 25 of 27 and 19 of 26 unique NFPE components in >80% of adults and children, respectively. Common reasons the full NFPE was not completed were limited mobility in adults and patient refusal in children. RDNs had lower odds of completing NFPEs in adults with lower vs higher education levels or higher vs lower nutrition complexity and in younger vs older children. CONCLUSION: RDNs evaluated NFPE components for a high proportion (>80%) of hospitalized patients.
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Hospitalização , Avaliação Nutricional , Nutricionistas , Exame Físico , Humanos , Feminino , Adolescente , Masculino , Criança , Adulto , Estudos Prospectivos , Lactente , Exame Físico/métodos , Pré-Escolar , Adulto Jovem , Pessoa de Meia-Idade , Nutricionistas/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Idoso , Estado Nutricional , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Força da Mão , Estudos de Viabilidade , Estados UnidosRESUMO
PURPOSE: While limited resources can make high-quality, comprehensive, coordinated cancer care provision challenging in rural settings, rural cancer patients often rely on local hospitals for care. To develop resources and strategies to support high-quality local cancer care, it is critical to understand the current experiences of rural cancer care physicians, including perceived strengths and challenges of providing cancer care in rural areas. METHODS: Semi-structured interviews were conducted with 13 cancer providers associated with all 12 non-metropolitan/rural Iowa hospitals that diagnose or treat >100 cancer patients annually. Iterative thematic analysis was conducted to develop domains. FINDINGS: Participants identified geographic proximity and sense of community as strengths of local care. They described decision-making processes and challenges related to referring patients to larger centers for complex procedures, including a lack of dedicated navigators to facilitate and track transfers between institutions and occasional lack of respect from academic physicians. Participants reported a desire for strengthening collaborations with larger urban/academic cancer centers, including access to educational opportunities, shared resources and strategies to collect and monitor data on quality, and clinical trials. CONCLUSIONS: Rural cancer care providers are dedicated to providing high-quality care close to home for their patients and would welcome opportunities to increase collaboration with larger centers to improve coordination and comprehensiveness of care, collect and monitor data on quality of care, and access continuing education opportunities. Further research is needed to develop implementation approaches that will extend resources, services, and expertise to rural providers to facilitate high-quality cancer care for all cancer patients.
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PURPOSE: The Commission on Cancer (CoC) establishes standards to support multidisciplinary, comprehensive cancer care. CoC-accredited cancer programs diagnose and/or treat 73% of patients in the United States. However, rural patients may experience diminished access to CoC-accredited cancer programs. Our study evaluated distance to hospitals by CoC accreditation status, rurality, and Census Division. METHODS: All US hospitals were identified from public-use Homeland Infrastructure Foundation-Level Data, then merged with CoC-accreditation data. Rural-Urban Continuum Codes (RUCC) were used to categorize counties as metro (RUCC 1-3), large rural (RUCC 4-6), or small rural (RUCC 7-9). Distance from each county centroid to the nearest CoC and non-CoC hospital was calculated using the Great Circle Distance method in ArcGIS. FINDINGS: Of 1,382 CoC-accredited hospitals, 89% were in metro counties. Small rural counties contained a total of 30 CoC and 794 non-CoC hospitals. CoC hospitals were located 4.0, 10.1, and 11.5 times farther away than non-CoC hospitals for residents of metro, large rural, and small rural counties, respectively, while the average distance to non-CoC hospitals was similar across groups (9.4-13.6 miles). Distance to CoC-accredited facilities was greatest west of the Mississippi River, in particular the Mountain Division (99.2 miles). CONCLUSIONS: Despite similar proximity to non-CoC hospitals across groups, CoC hospitals are located farther from large and small rural counties than metro counties, suggesting rural patients have diminished access to multidisciplinary, comprehensive cancer care afforded by CoC-accredited hospitals. Addressing distance-based access barriers to high-quality, comprehensive cancer treatment in rural US communities will require a multisectoral approach.
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BACKGROUND: The lack of a widely accepted, broadly validated tool for diagnosing malnutrition in hospitalized patients limits the ability to assess the integral role of nutrition as an input and outcome of health, disease, and treatment. OBJECTIVES: This study aimed to evaluate the predictive validity of the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition (ASPEN) indicators to diagnose malnutrition (AAIM) tool and determine if it can be simplified. METHODS: A prospective cohort study was conducted from August 2019 to September 2022 with 32 hospitals in United States. At baseline, 290 adult patients were evaluated for a diagnosis of malnutrition using the AAIM tool, which assesses weight loss, inadequate energy intake, subcutaneous fat and muscle loss, edema, and hand grip strength. Healthcare outcomes were extracted from the medical record: composite incidence of emergency department (ED) visits and hospital readmissions within 90 d postdischarge; length of hospital stay (LOS); and Medicare Severity Disease Related Group (MS-DRG) relative weight (i.e., healthcare resource utilization). We used multilevel, multivariable negative binomial or generalized linear regression models to evaluate relationships between malnutrition diagnosis and healthcare outcomes. RESULTS: After adjusting for disease severity and acuity and sociodemographic characteristics, individuals diagnosed with severe malnutrition had a higher incidence rate of ED visits and hospital readmissions (incidence rate ratio: 1.89; 95% CI: 1.14, 3.13; P = 0.01), and individuals diagnosed with moderate malnutrition had a 25.2% longer LOS (95% CI: 2.0%, 53.7%; P = 0.03) and 15.1% greater healthcare resource utilization (95% CI: 1.6%, 31.9%; P = 0.03) compared with individuals with no malnutrition diagnosis. Observed relationships remained consistent when only considering malnutrition diagnoses supported by at least 2 of these indicators: weight loss, subcutaneous fat loss, muscle wasting, and inadequate energy intake. CONCLUSIONS: Findings from this multihospital study confirm the predictive validity of the original or simplified AAIM tool and support its routine use for hospitalized adult patients. This trial was registered at clinicaltrials.gov as NCT03928548 (https://classic. CLINICALTRIALS: gov/ct2/show/NCT03928548).