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A collaborative effort between experiment and theory toward elucidating the electronic and molecular structures of uranium-gold clusters is presented. Anion photoelectron spectra of UAun-(n = 3-7) were taken at the third (355 nm) and fourth (266 nm) harmonics of a Nd:YAG laser, as well as excimer (ArF 193 nm) photon energies, where the experimental adiabatic electron affinities and vertical detachment energies values were measured. Complementary first-principles calculations were subsequently carried out to corroborate experimentally determined electron detachment energies and to determine the geometry and electronic structure for each cluster. Except for the ring-like neutral isomer of UAu6 where one unpaired electron is spread over the Au atoms, all other neutral and anionic UAun clusters (n = 3-7) were calculated to possess open-shell electrons with the unpaired electrons localized on the central U atom. The smaller clusters closely resemble the analogous UFn species, but significant deviations are seen starting with UAu5 where a competition between U-Au and Au-Au bonding begins to become apparent. The UAu6 system appears to mark a transition where Au-Au interactions begin to dominate, where both a ring-like and two heavily distorted octahedral structures around the central U atom are calculated to be nearly isoenergetic. With UAu7, only ring-like structures are calculated. Overall, the calculated electron detachment energies are in good agreement with the experimental values.
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Here, anion photoelectron spectroscopy and first-principles quantum chemistry are used to demonstrate to what degree Au can act as a surrogate for F in UF6 and its anion. Unlike UF6, UAu6 exhibits strong ligand-ligand, i.e., Au-Au, interactions, resulting in three low-lying isomers, two of which are three-dimensional while the third isomer has a ring-like quasi two-dimensional structure. Additionally, all the UAu6 isomers have open-shell electrons, which in nearly all cases are localized on the central U atom. The adiabatic electron affinity and vertical detachment energy are measured to be 3.05 ± 0.05 and 3.28 ± 0.05 eV, respectively, and are in very good agreement with calculations.
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Electrones , Ligandos , Espectroscopía de Fotoelectrones , Aniones/química , IsomerismoRESUMEN
The results of ab initio correlated molecular orbital theory electronic structure calculations for low-lying electronic states are presented for UH and UH- and compared to photoelectron spectroscopy measurements. The calculations were performed at the CCSD(T)/CBS and multireference CASPT2 including spin-orbit effects by the state interacting approach levels. The ground states of UH and UH- are predicted to be 4Ι9/2 and 5Λ6, respectively. The spectroscopic parameters Te, re, ωe, ωexe, and Be were obtained, and potential energy curves were calculated for the low energy Ω states of UH. The calculated adiabatic electron affinity is 0.468 eV in excellent agreement with an experimental value of 0.462 ± 0.013 eV. The lowest vertical detachment energy was predicted to be 0.506 eV for the ground state, and the adiabatic ionization energy (IE) is predicted to be 6.116 eV. The bond dissociation energy (BDE) and heat of formation values of UH were obtained using the IE calculated at the Feller-Peterson-Dixon level. For UH, UH-, and UH+, the BDEs were predicted to be 225.5, 197.9, and 235.5 kJ/mol, respectively. The BDE for UH is predicted to be â¼20% lower in energy than that for ThH. The analysis of the natural bond orbitals shows a significant U+H- ionic component in the bond of UH.
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Mass spectrometric analysis of anionic products that result from interacting Ir- with H2O shows the efficient generation of [Ir(H2O)]- complexes and IrO- molecular anions. Anion photoelectron spectra of [Ir(H2O)]-, formed under various source conditions, exhibit spectral features that are due to three different forms of the complex: the solvated anion-molecule complex, Ir-(H2O), as well as the intermediates, [H-Ir-OH]- and [H2-Ir-O]-, where one and two O-H bonds have been broken, respectively. The measured and calculated vertical detachment energy values are in good agreement and, thus, support identification of all three types of isomers. The calculated reaction pathway shows that the overall reaction Ir- + H2O â IrO- + H2 is exothermic. Two minimum energy crossing points were found, which shuttle intermediates and products between singlet and triplet potential surfaces. This study presents the first example of water activation and splitting by single Ir- anions.
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To explore prostate and depression screening practices as well as predictors for prostate screening among a diverse group of men seen at a nurse-led community health center. This was a retrospective, exploratory study. Social factors, depression, and prostate screening data on 267 male patients were retrieved from medical records from 2014 to 2018. Patients that were not screened for depression were associated with a lower probability of having received a PSA screening (OR = .40, p = 02). Of those screened for depression, higher scores were associated with lower PSA screening (OR = .89, p = .02). Patients who self-identified as Hispanic (OR = .19, p <. 001), African American (AA) (OR = .06, P = .01) or White (OR = .12, P = .02) had lower odds of PSA screening compared to Black-Caribbean. The above clinical evidence is a practice implication for nurses and health care professionals. Depression screening predicted higher rates of prostate screening, while higher depression scores predicted lower prostate screening. AA and Hispanic subgroups were less likely to be screened for prostate cancer than the non-U.S. born Black-Caribbean men. Findings underscore the importance of developing community-based culturally sensitive approaches to prostate preventative care. Nurses and health providers must understand that diversity within the "Black" population exists, and these differences drive health behaviors. Person-centered care that is culturally sensitive will be essential in developing trust with communities of color to increase prostate cancer screening and health equity.
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Depresión , Detección Precoz del Cáncer , Disparidades en el Estado de Salud , Neoplasias de la Próstata , Población Negra , Centros Comunitarios de Salud , Depresión/diagnóstico , Depresión/etnología , Humanos , Masculino , Próstata , Antígeno Prostático Específico , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/etnología , Neoplasias de la Próstata/prevención & control , Salud Pública , Estudios RetrospectivosRESUMEN
BACKGROUND: African American women have an elevated risk for experiencing depressive symptoms, and discrimination, stress, and coping contribute to symptoms of depression. AIMS: We aimed to examine the associations between discrimination, stress, and coping on symptoms of depression among young African American mothers. METHODS: In this retrospective study, we utilized a hierarchical linear regression to explore the effects of perceived racial discrimination, stress, and general and discrimination-related coping responses on depressive symptoms in a sample of African American mothers (N = 250). The data were drawn from the Intergenerational Impact of Genetic and Psychological Factors on Blood Pressure study (InterGEN), a study conducted between 2014 and 2019 and based in Connecticut. RESULTS: After accounting for maternal age, level of education, and income, greater perceived racial discrimination (p = .03), higher levels of stress (p < .001), greater engagement in avoidance coping (p < .001), and use of passive coping responses to discrimination (p = .04) were uniquely associated with increased depressive symptoms. Other forms of coping, specifically, problem-solving and support seeking, did not appear to influence depressive symptoms in this sample. CONCLUSION: The findings highlight the negative impact of discrimination, heightened stress, and maladaptive coping on the emotional health of young African American mothers.
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Understanding direct metal-metal bonding between actinide atoms has been an elusive goal in chemistry for years. We report for the first time the anion photoelectron spectrum of U2-. The threshold of the lowest electron binding energy (EBE) spectral band occurs at 1.0 eV, which corresponds to the electron affinity (EA) of U2, whereas the vertical detachment energy of U2- is found at EBE â¼ 1.2 eV. Electronic structure calculations on U2 and U2- were carried out with state-of-the-art theoretical methods. The computed values of EA(U2) and EA(U) and the difference between the computed dissociation energies of U2 and U2- are found to be internally consistent and consistent with experiment. Analysis of the bonds in U2 and U2- shows that while U2 has a formal quintuple bond, U2- has a quadruple bond, even if the effective bond orders differ only by 0.5 unit instead of one unit. The resulting experimental-computational synergy elucidates the nature of metal-metal bonding in U2 and U2-.
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The observation and characterization of the anions: Th2O-, Th2Au-, and Th2AuO1,2- is reported. These species were studied through a synergetic combination of anion photoelectron spectroscopy and ab initio correlated molecular orbital theory calculations at the CCSD(T) level with large correlation-consistent basis sets. To better understand the energetics and bonding in these anions and their corresponding neutrals, a range of smaller diatomic to tetratomic species were studied computationally. Correlated molecular orbital theory calculations at the CCSD(T) level showed that in most of these cases, there are close-lying anions and neutral clusters with different geometries and spin states and are consistent with the experimentally observed spectra. Thus, comparison of experimentally determined and computationally predicted vertical detachment energies and electron affinities for different optimized geometries and spin states shows excellent agreement to within 0.1 eV. The structures for both the neutrals and anions have a significant ionic component to the bonding because of the large electron affinity of the Au atom and modest ionization potentials for Th2, Th2O, and Th2O2. The analysis of the bonding for the Th-Th bonds from the molecular orbitals is consistent with this ionic model. The results show that there is a wide variation in the bond distance from 2.7 to 3.5 Å for the Th-Th bonds all of which are less than twice the atomic radius of Th of 3.6 Å. The bond distances encompass bond orders from 4 to 0. There can be different bond orders for the same bond distance depending on the nature of the ionic bonding suggesting that one may not be able to correlate the bond order with the bond distance in these types of clusters. In addition, the presence of an Au atom may provide a unique probe of the bonding in such clusters because of its ability to accept an electron from clusters with modest ionization potentials.
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Elucidating the multifaceted processes of molecular activation and subsequent reactions gives a fundamental view into the development of iridium catalysts as they apply to fuels and propellants, for example, for spacecraft thrusters. Hydroxylamine, a component of the well-known hydroxylammonium nitrate (HAN) ionic liquid, is a safer alternative and mimics the chemistry and performance standards of hydrazine. The activation of hydroxylamine by anionic iridium clusters, Irn- (n = 1-5), depicts a part of the mechanism, where two hydrogen atoms are removed, likely as H2, and Irn(NOH)- clusters remain. The significant photoelectron spectral differences between these products and the bare clusters illustrate the substantial electronic changes imposed by the hydroxylamine fragment on the iridium clusters. In combination with DFT calculations, a preliminary reaction mechanism is proposed, identifying the possible intermediate steps leading to the formation of Ir(NOH)-.
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The results of a combined experimental and computational study of the uranium atom are presented with the aim of determining its electron affinity. Experimentally, the electron affinity of uranium was measured via negative ion photoelectron spectroscopy of the uranium atomic anion, U-. Computationally, the electron affinities of both thorium and uranium were calculated by conducting relativistic coupled-cluster and multi-reference configuration interaction calculations. The experimentally determined value of the electron affinity of the uranium atom was determined to be 0.309 ± 0.025 eV. The computationally predicted electron affinity of uranium based on composite coupled cluster calculations and full four-component spin-orbit coupling was found to be 0.232 eV. Predominately due to a better convergence of the coupled cluster sequence for Th and Th-, the final calculated electron affinity of Th, 0.565 eV, was in much better agreement with the accurate experimental value of 0.608 eV. In both cases, the ground state of the anion corresponds to electron attachment to the 6d orbital.
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PURPOSE: The association between symptoms of depression and risks for cardiovascular disease (CVD) remains equivocal for African American (AA) mothers. We examined the association between social determinants of health (perceived discrimination), and cardiovascular risk (BMI) on symptoms of depression in a sample of young AA mothers. METHODS: Secondary data from 219 adult AA mothers between the ages of 21 and 46 with an average BMI of 29.8 and yearly family income of $14,999 were analyzed using a latent growth model that evaluated four time points to assess changes in symptoms of depression. RESULTS: Initial BMI was significantly associated with initial symptoms of depression (b = 0.12, p = .019). Perceived discrimination (unfair treatment) was associated with higher initial symptoms of depression (b = 1.14, p = .017). CONCLUSION: The findings suggest that elevated BMI and perceived discrimination are associated with higher reported symptoms of depression among young, socioeconomically disadvantaged AA mothers. These results advance the scientific understanding of young AA mothers' risk for symptoms of depression and CVD by elucidating the impact of perceived discrimination and social experiences on mental health. Further studies of SDoH and CVD risk factors and perceived racism and depression are needed to shed light on the long-term mental health impact on AA mothers and their children.
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Negro o Afroamericano , Índice de Masa Corporal , Madres , Determinantes Sociales de la Salud , Adulto , Niño , Depresión , Femenino , Humanos , Persona de Mediana Edad , Racismo , Adulto JovenRESUMEN
The p-chloroaniline anion was generated by Rydberg electron transfer and studied via velocity-map imaging anion photoelectron spectroscopy. The vertical detachment energy (VDE) of the p-chloroaniline anion was measured to be 6.6 meV. This value is in accord with the VDE of 10 meV calculated by Skurski and co-workers. They found the binding of the excess electron in the p-chloroaniline anion to be due almost entirely to electron correlation effects, with only a small contribution from the long-range dipole potential. As such, the p-chloroaniline anion is the first essentially correlation-bound anion to be observed experimentally.
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BACKGROUND: High sodium diets with inadequate potassium and high sodium-to-potassium ratios are a known determinant of hypertension and cardiovascular disease (CVD). The Caribbean island of Barbados has a high prevalence of hypertension and mortality from CVD. Our objectives were to estimate sodium and potassium excretion, to compare estimated levels with recommended intakes and to identify the main food sources of sodium in Barbadian adults. METHODS: A sub-sample (n = 364; 25-64 years) was randomly selected from the representative population-based Health of the Nation cross-sectional study (n = 1234), in 2012-13. A single 24-h urine sample was collected from each participant, following a strictly applied protocol designed to reject incomplete samples, for the measurement of sodium and potassium excretion (in mg), which were used as proxy estimates of dietary intake. In addition, sensitivity analyses based on estimated completeness of urine collection from urine creatinine values were undertaken. Multiple linear regression was used to examine differences in sodium and potassium excretion, and the sodium-to-potassium ratio, by age, sex and educational level. Two 24-h recalls were used to identify the main dietary sources of sodium. All analyses were weighted for the survey design. RESULTS: Mean sodium excretion was 2656 (2488-2824) mg/day, with 67% (62-73%) exceeding the World Health Organization (WHO) recommended limit of 2000 mg/d. Mean potassium excretion was 1469 (1395-1542) mg/d; < 0.5% met recommended minimum intake levels. Mean sodium-to-potassium ratio was 2.0 (1.9-2.1); not one participant had a ratio that met WHO recommendations. Higher potassium intake and lower sodium-to-potassium ratio were independently associated with age and tertiary education. Sensitivity analyses based on urine creatinine values did not notably alter these findings. CONCLUSIONS: In this first nationally representative study with objective assessment of sodium and potassium excretion in a Caribbean population in over 20 years, levels of sodium intake were high, and potassium intake was low. Younger age and lower educational level were associated with the highest sodium-to-potassium ratios. These findings provide baseline values for planning future policy interventions for non-communicable disease prevention.
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Población Negra/estadística & datos numéricos , Enfermedades Cardiovasculares/epidemiología , Dieta/estadística & datos numéricos , Potasio/orina , Sodio/orina , Adulto , Barbados/epidemiología , Enfermedades Cardiovasculares/etnología , Enfermedades Cardiovasculares/orina , Estudios Transversales , Dieta/efectos adversos , Encuestas sobre Dietas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Potasio/análisis , Prevalencia , Sodio en la Dieta/análisisRESUMEN
OBJECTIVE: To elucidate how and in what ways cumulative violence affects health-related quality of life (HRQoL) among a clinical cohort of virally stable people living with HIV. DESIGN: We used data from the University of North Carolina Center for AIDS Research HIV clinical cohort. Our analysis was limited to participants with an undetectable viral load (<200) and those who completed the Clinical, Sociodemographic, and Behavioral Survey between 2008 and 2017 ( n = 284). METHODS: A path analysis was used to test our primary hypothesis that the effect of cumulative violence on HRQoL would be mediated through symptoms of post-traumatic stress disorder (PTSD), depressive symptoms, and HIV symptom distress. RESULTS: The impact of cumulative violence on HRQoL was fully mediated by symptoms of PTSD, depressive symptoms, and HIV symptom distress. Greater exposure to violence was associated with higher odds of PTSD symptoms ( P <0.001), increased depressive symptoms ( P <0.001), and increased HIV symptom distress ( P < 0.01). HIV symptom distress displayed the largest association with HRQoL ( P < 0.001), followed by depressive symptoms ( P = 0.001) and PTSD symptoms ( P < 0.001). These factors explained approximately 51% of the variance in HRQoL ( R2 = 0.51, P < 0.001). CONCLUSIONS: Our findings indicate that addressing physical and mental health symptoms rooted in violent victimization should be a point of focus in efforts to improve HRQoL among people living with HIV who are virally stable.
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Acoso Escolar , Infecciones por VIH , Humanos , Calidad de Vida , Infecciones por VIH/complicaciones , ViolenciaRESUMEN
Our objective was to describe, for the first time in an English-speaking Caribbean country, the contribution of ultra-processed foods (UPFs) to nutrients linked to non-communicable disease. Using a cross-sectional study design, dietary data were collected from two non-consecutive 24-h dietary recalls. Recorded food items were then classified according to their degree of processing by the NOVA system. The present study took place in Barbados (2012-13). A representative population-based sample of 364 adult Barbadians (161 males and 203 females) aged 25-64 years participated in the study. UPFs represented 40â 5 % (838 kcal/d; 95 % CI 791, 885) of mean energy intake. Sugar-sweetened beverages made the largest contribution to energy within the UPF category. Younger persons (25-44 years) consumed a significantly higher proportion of calories from UPF (NOVA group 4) compared with older persons (45-64 years). The mean energy shares of UPF ranged from 22â 0 to 58â 9 % for those in the lowest tertile to highest tertile. Within each tertile, the energy contribution was significantly higher in the younger age group (25-44 years) compared with the older (45-64 years). One-quarter of persons consume ≥50 % of their daily calories from UPF, this being significantly higher in younger persons. The ultra-processed diet fraction contained about six times the mean of free sugars and about 0â 8 times the dietary fibre of the non-ultra-processed fraction (NOVA groups 1-3). Targeted interventions to decrease the consumption of UPF especially in younger persons is thus of high priority to improve the diet quality of Barbadians.
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Dieta , Comida Rápida , Adulto , Barbados , Estudios Transversales , Ingestión de Energía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades no Transmisibles/epidemiología , Bebidas AzucaradasRESUMEN
Background: The Session Rating Scale (SRS) is a measure used in psychotherapy practice. Given its application and frequent use in clinical practice settings, several studies including primary validation studies as well as outcome studies reporting psychometric properties have examined the validity and reliability of the SRS. Because the SRS is designed to be used in clinical practice, demonstration of reliability and validity is ideal with clinical populations instead of non-clinical populations. To our knowledge, there have been no reviews evaluating the psychometric properties of the SRS with clinical populations.Purpose: The aim of this study was to review and synthesize the psychometric properties of the SRS by examining all relevant outcome and validation studies.Methods: We completed an electronic literature search of several online databases in order to identify relevant articles. We identified 12 articles that met our inclusion and analyzed the reliability and validity evidence for the SRS with clinical populations.Results: Findings showed high internal consistency for the SRS and support evidence that the underlying dimension is a measure of therapeutic alliance. Test-retest reliability estimates were reported in 4 of the 12 studies included in this review (ranging from .54 to .70). The SRS had low to moderate concurrent validity with other longer measures of therapeutic alliance (.29 with ORS; .48 with HAQ II; .57-.65 with WAI).Discussion: Clinicians should be aware of the limitations in validity evidence for the SRS that may result from its brevity. However, clinicians should also consider the relative stability of the SRS as a pragmatic global measure of the construct of therapeutic alliance. Future research efforts should focus on validation of the SRS with larger, more diverse samples and specific clinical populations with a wider range of symptom severity.
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Guías de Práctica Clínica como Asunto , Psicología/normas , Psicometría/métodos , Psicoterapia/normas , Servicio Social/organización & administración , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y CuestionariosRESUMEN
The Caribbean island of Barbados has a high burden of diabetes and cardiovascular disease. Dietary habits were last described in 2005. A representative population-based sample (n = 363, aged 25-64 years) provided two nonconsecutive 24-hr dietary recalls in this cross-sectional study. Mean daily nutrient intakes were compared with the Dietary Guidelines for Americans. Subgroup differences by age, sex, and educational level were examined using logistic regression. High sugar intakes exist for both sexes with 24% (95% CIs 18.9, 30.0) consuming less than the recommended <10% of energy from added sugars (men 22%; 15.0, 31.6; women 26%; 18.9, 33.7). Sugar-sweetened beverages provide 43% (42.2%, 44.4%) of total sugar intake. Inadequate dietary fiber intakes (men 21 g, 18.2, 22.8; women 18 g, 16.7, 18.9) exist across all age groups. Inadequate micronutrient intake was found in women for calcium, folate, thiamine, zinc, and iron. Older persons (aged 45-64 years) were more likely to report adequacy of dietary fiber (OR = 2.7, 1.5, 4.8) and iron (OR = 3.0, 1.7, 5.3) than younger persons (aged 25-44). Older persons (aged 45-64 years) were less likely to have an adequate supply of riboflavin (OR = 0.4, 0.2, 0.6) than younger persons. Men were more likely to have adequate intakes of iron (OR = 13.0, 6.1, 28.2), folate (OR = 2.4, 1.3, 4.6), and thiamine (OR = 3.0, 1.5, 5.0) than women. Education was not associated with nutrient intake. The Barbadian diet is characterized by high sugar intakes and inadequate dietary fiber; a nutrient profile associated with an increased risk of obesity, type 2 diabetes, and related noncommunicable diseases.