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1.
Nutrients ; 16(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38732585

RESUMO

BACKGROUND: This study aimed to examine the prevalence and associated factors of malnutrition in older community-dwellers and explore the interaction between associated factors. METHODS: A total of 474,467 older community-dwellers aged 65 or above were selected in Guangzhou, China. We used a two-step methodology to detect the associated factors of malnutrition and constructed logistic regression models to explore the influencing factors and interactive effects on three patterns of malnutrition. RESULTS: The prevalence of malnutrition was 22.28%. Older adults with both hypertension and diabetes (RERI = 0.13), both meat or fish diet and hypertension (RERI = 0.79), and both meat or fish diet and diabetes (RERI = 0.81) had positive additive interaction effects on the risk of obesity, whereas those on a vegetarian diet with hypertension (RERI = -0.25) or diabetes (RERI = -0.19) had negative additive interaction effects. Moreover, the interactions of physical activity with a meat or fish diet (RERI = -0.84) or dyslipidemia (RERI = -0.09) could lower the risk of obesity. CONCLUSIONS: Malnutrition was influenced by different health factors, and there were interactions between these influencing factors. Pertinent dietary instruction should be given according to different nutritional status indexes and the prevalence of metabolic diseases to avoid the occurrences of malnutrition among older adults.


Assuntos
Mineração de Dados , Hipertensão , Desnutrição , Humanos , Idoso , China/epidemiologia , Masculino , Feminino , Desnutrição/epidemiologia , Prevalência , Hipertensão/epidemiologia , Fatores de Risco , Idoso de 80 Anos ou mais , Vida Independente , Estado Nutricional , Diabetes Mellitus/epidemiologia , Obesidade/epidemiologia , Dieta , Exercício Físico , Modelos Logísticos , Dislipidemias/epidemiologia
2.
Inorg Chem ; 62(42): 17052-17056, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37815023

RESUMO

Designing and innovating organic structure-directing agents is the key to synthesizing novel molecular sieve structures. Herein, we design a novel carbazolyl-modified template and further synthesize a two-dimensional layered aluminophosphate with [C17H21N2]3[Al3(PO4)4]·5H2O (denoted as ZHKU-2). ZHKU-2 is composed of AA-stacked [Al3P4O16]3- layers constructed from alternating AlO4 and PO3(=O) tetrahedrons to form a 4.6.8 network featured by capped six-ring secondary building units. Carbazolyl-templated ZHKU-2 exhibits strong purple fluorescence with a high quantum yield of 25.98%. This work expands aluminophosphate materials of the [Al3P4O16]3- family and provides a view for synthesizing new molecular sieves by exploring the organic luminescence structure-directing agents.

3.
Front Public Health ; 11: 1251858, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37780423

RESUMO

Introduction: As a developing country with the largest older adult population in the world, strengthening the research on falls among the older adults is undoubtedly an urgent item in China. This study aimed to explore the prevalence and risk factors associated with falls and injury from falls among community-dwelling older adults in Guangzhou, China, particularly focusing on their associations with chronic diseases. Methods: A total of 1,629 participants aged 65 years and above were selected from 11 counties in Guangzhou by the multi-stage stratified random sampling method in 2021. Socio-demographic characteristics, health and lifestyle factors, the status of falls, and injury from falls were measured by structured questionnaires through face-to-face interviews. Chi-square tests and logistic regression analysis were used to identify factors associated with falls and injury from falls. Chord diagrams were used to explore their associations with chronic diseases. Results: A total of 251 participants (15.41%, 95% CI: 13.98%-17.25%) reported falls, and 162 participants (9.46%, 95% CI:7.72%-11.55%) indicated an injury from falls. Logistic regression analysis showed the results as follows: female patients (adjusted OR = 1.721, 95% CI: 1.681-1.761) aged ≥80 years (1.910, 1.847-1.975), unemployed (1.226, 1.171-1.284), uninsured (1.555, 1.448-1.671), average monthly household income of 2,001-4,000 CNY (1.878, 1.827-1.930), number of services provided by the community health center ≥13 times per year (1.428, 1.383-1.475), illness within 2 weeks (1.633, 1.595-1.672), high-intensity physical activity (2.254, 2.191-2.32), sedentary (1.094, 1.070-1.117), and number of chronic disease illnesses ≥3 (1.930, 1.870-1.993). Meanwhile, those risk factors were also associated with injury from falls. The older adults with medium-intensity physical activity were at lower risk (0.721, 0.705-0.737) of falls and higher risk (1.086, 1.057-1.117) of being injured from falls. Chord diagrams showed the correlations between chronic diseases and falls and injury from falls among community-dwelling older adults in Guangzhou, China. Conclusion: The high prevalence of falls is found among community-dwelling older adults in Guangzhou, China, which is related to multiple factors such as demographic variables, lifestyle, and health status, especially for chronic diseases. Therefore, targeted interventions should be developed and implemented urgently.


Assuntos
Vida Independente , Humanos , Feminino , Idoso , Estudos Transversais , Prevalência , China/epidemiologia , Doença Crônica
4.
Environ Pollut ; 334: 122192, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37451591

RESUMO

Biofilms play a significant role in the biogeochemical processing of organic matter and the environmental fate of emerging pollutants. In this study, we investigated the occurrence and distribution of 32 endocrine-disrupting chemicals (EDCs), including 24 environmental corticosteroids (ECs) and 8 environmental estrogens (EEs), in natural biofilms from the Pearl River system. Their association between biofilms and water and environmental risk were assessed. The ECs and EEs ubiquitously occurred in the biofilms, ranging from <0.61-6.57 ng/g and <0.8-2535 ng/g, respectively. Temporally, there was no obvious variance in either ECs or EEs in the biofilms during the winter and summer, and their concentrations exhibited a spatial trend of upward to midstream, descending downstream, and then seaward attenuation at the estuary. For ECs and EEs, the similar levels of field-derived bioconcentration factors (BCFs) (logarithm values: 2.42-2.86 and 2.72-2.98, respectively) and biofilm organic carbon-normalized partitioning coefficients (Kboc) (3.39-3.69 and 3.35-3.95) suggest the comparable potential of accumulation and sorption by biofilms between these two classes of EDCs. In addition, higher values of BCF and Kboc for the EEs were found in winter and were correspondingly comparable to their distribution coefficients (Kd) and Koc derived from suspended particles and sediment, revealing that biofilms are a competitive environmental compartment for capturing EDCs, particularly during the mature period. A positive logKboc-logKow relationship suggests hydrophobic partitioning as a primary interaction mechanism between the biofilm and EEs. Moreover, high risks from biofilm-associated ECs and EEs might have posed to the fluvial ecosystem. This study provides original insights into the occurrence, fate, and risk of ECs in natural biofilms for the first time and demonstrates that biofilms may not only serve as reservoirs but also serve as sentinels for fluvial EDC contamination. These results contribute to the further understanding of the behavior and fate of EDCs in aquatic environments.


Assuntos
Disruptores Endócrinos , Poluentes Químicos da Água , Estrogênios , Prevalência , Ecossistema , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Corticosteroides , Disruptores Endócrinos/análise , Biofilmes , China
5.
Sci Total Environ ; 884: 163701, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37105482

RESUMO

Suspended particulate matter (SPM) plays an important role in the geochemical behavior and fate of organic micropollutants in aquatic environments. However, the presence of trace emerging endocrine disruptors such as environmental corticosteroids (ECs) in SPM is less well understood. This study focused on the occurrence, distribution, and partitioning of SPM-associated ECs in the Pearl River system, China. Ubiquitous particulate ECs were found in the surface water of the rivers at average concentrations (dry weight) between 0.46 ng/g (flumethasone) and 8.83 ng/g (clobetasone butyrate). The total EC (∑ECs) concentrations of the 24 selected target compounds varied from <1.03 ng/g to 62.3 ng/g, with an average and median of 17.6 ng/g and 13.7 ng/g, respectively. Higher SPM-bound EC levels were commonly observed in winter (dry season), and spatially, their relatively high contamination in urban tributary networks decreased while flowing to mainstreams and then gradually attenuated from upstream to the estuary. Despite the approximately 90 % mass distribution of ∑ECs in the aqueous phase, approximately 50 % of their effect burden was derived from the suspended particulate fractions. For the first time, in situ SPM-water partitioning coefficients (Kp) and their organic carbon-normalized ones (Koc) of ECs were determined in surface waters, and a field-derived preliminary linear equation was proposed to estimate Koc for ECs using basic physicochemical parameters n-octanol/water partitioning coefficient (Kow), which is of importance with regard to the assessment of transport, fate, and risk of these emerging hazardous chemicals. Furthermore, the significant logKoc-logKow relationship for ECs reveals that nonspecific hydrophobic partitioning is a major association mechanism between SPM and ECs. Moreover, hydrogen bonding is suggested to be a prevailing specific binding mechanism and provides more contribution to nonhydrophobic interactions between ECs and particulate organic matter than environmental estrogens.


Assuntos
Rios , Poluentes Químicos da Água , Rios/química , Poluentes Químicos da Água/análise , Material Particulado/análise , Corticosteroides , Água , China , Poeira , Monitoramento Ambiental , Sedimentos Geológicos/química
6.
Heliyon ; 8(10): e10863, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36254282

RESUMO

Introduction: With rapid increase in the aging population, falls injuries have become an important public health problem. However, limited data have been reported on the associations between meteorological factors and falls injuries in the elderly. This study assessed the epidemiology of falls injuries and explored this association in the elderly in Guangzhou, China. Methods: Data on elderly falls injury cases and meteorological variables from 2014 to 2018 in Guangzhou were collected from the Guangzhou Injury Monitoring System and Guangzhou Meteorological Bureau, respectively. The monthly average data on falls injuries and meteorological factors were applied to the data analysis. These correlations were conducted using Pearson correlation analysis. A multiple linear regression model was used to estimate the effects of meteorological factors on falls injuries in the elderly in Guangzhou, China. Results: Accounting for 49.41% of causes of elderly injury were falls in the Guangzhou Injury Monitoring System from 2014 to 2018, which occupied first place for five consecutive years. The monthly number of elderly falls injury cases was lowest in April and highest in December, and had a positive correlation with monthly mean wind speed (r = 0.187, P < 0.01) and a negative correlation with monthly atmospheric pressure (r = -0.142, P < 0.05). A multiple linear regression model was constructed (F = 10.176, P < 0.01), which explained 23.7% of the variances (R 2 = 0.237). Monthly mean wind speed (ß = 76.85, P < 0.01) and monthly mean atmospheric pressure (ß = -3.162, P < 0.01) were independent factors affecting monthly elderly falls injuries. Conclusions: Falls are the primary cause of injury among elderly people in Guangzhou, China. Meteorological factors are related to falls injuries in the elderly population. Decreasing activity during high wind and low atmospheric pressure weather may help reduce the number of elderly falls injury cases.

7.
Dalton Trans ; 51(33): 12661-12669, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35938501

RESUMO

Based on the uncommon Kramers ions CeIII, SmIII and YbIII, complexes [Ce(dppbO2)2Cl3] (1, dppbO2 = 1,2-bis(diphenylphosphino)benzene dioxide), [Sm(dppbO2)2Cl3] (2) and [Yb(dppbO2)2Cl2]Cl (3) toward single-ion magnets were obtained and fully characterized. Complexes 1 and 2 are isostructural seven-coordinate with distorted geometries between a capped trigonal prism and a capped octahedron, while 3 is six-coordinate with an octahedral geometry. Dynamic magnetic property measurements reveal their field induced slow magnetic relaxation behaviours. Fits to the temperature dependent relaxation time (τ) result in effective barriers of 38(2), 11.7(2) and 20.2(6) cm-1 for 1, 2 and 3, respectively, as well as relatively low Raman exponents (3.4(2) for 1 and 2.1(1) for 3). Ab initio calculations were then performed and they indicated that the first excited Kramers doublets (KDs) for 1, 2 and 3 lie at ca. 291, 63.5 and 137 cm-1, respectively, which are much higher than the fitting results. Combining the significant transverse magnetic moments between the ground state KDs and the first excited KDs, we thus attribute the dominant relaxation pathway of the three compounds to a Raman process, while quantum tunnelling of magnetization and direct relaxation processes may coexist. In this case, the obtained effective barriers in a high temperature region for 1 and 3 are actually the energies of the vibrational modes, which lead to second-order Raman processes with exponential temperature dependence.

8.
Inorg Chem ; 61(26): 9897-9905, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35730617

RESUMO

A substituent decorating strategy for modification of the functional cavity is of great importance in the design of metal-organic frameworks (MOFs). Herein, three new isostructural cationic MOFs, [Cu3(Xpip)2]·NO3·nH2O (Xpip stands for X-substituted phenylimidazophenanthroline, where X = adm (SCNU-2), f (SCNU-3), and none for SCNU-4), have been successfully synthesized and shown gyroidal utc-c topology and large pore sizes which can be adjusted by different substituents (-N(CH3)2, -F, and -H). Interestingly, the differences of the substituents (sizes and proton donor/acceptor) show essential effects on the adsorption abilities of carbon dioxide and dyes, where SCNU-4 exhibits the highest CO2 affinity and the biggest adsorption capacity for anionic dyes Fluorescein Sodium, and SCNU-3 adsorbs the largest amount (1503.6 mg/g) of Acid Fuchsin to date for the reported porous materials. The detailed studies in adsorption kinetics, adsorption isotherms, and theoretical calculation of the binding energies between the structures and dye molecules confirm that the electric properties of the frameworks (cationic) and substituents directed to the pore surface are two important factors dramatically affecting the selective dye adsorption.

9.
BMJ Open ; 12(5): e056135, 2022 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-35613781

RESUMO

OBJECTIVES: Examination of the prevalence, influence factors and patterns of multimorbidity among the elderly people in Guangzhou, China. DESIGN: Cross-sectional study. PARTICIPANTS: 31 708 community-dwelling elderly people aged 65 and over. PRIMARY AND SECONDARY OUTCOME MEASURES: Prevalence, influence factors and patterns of multimorbidity in seven chronic conditions among the participants. A multistage, stratified random sampling was adopted for selection of health records in the residents' health records system of Guangzhou. Data mining by association rule mining analysis was used to explore the correlations and multimorbidity patterns between seven chronic diseases. RESULTS: The prevalence of morbidity was 55.0% (95% CI 40.1% to 60.1%) and the multimorbidity was 15.2% (95% CI 12.4% to 18.4%) among the participants. Elderly, women, higher education level, being single, living in urban areas and having medical insurance were more likely to have chronic diseases and multimorbidity. Data mining by association rule mining analysis reveals patterns of multimorbidity among the participants, including coexistence of hypertension and diabetes (support: 12.5%, confidence: 17.6%), hypertension and coronary heart disease (support: 4.4%, confidence: 5.7%), diabetes and coronary heart disease (support: 1.6%, confidence: 5.7%), diabetes, coronary heart disease and hypertension (support: 1.4%, confidence: 4.4%). CONCLUSIONS: A high prevalence of morbidity (especially on hypertension and diabetes) and a relatively low multimorbidity of chronic diseases exist in elderly people. Data mining of residents' health records will help for strengthening the management of residents' health records in community health service centres of Guangzhou, China.


Assuntos
Diabetes Mellitus , Hipertensão , Idoso , China/epidemiologia , Doença Crônica , Estudos Transversais , Mineração de Dados , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Vida Independente , Multimorbidade , Prevalência
10.
Molecules ; 27(5)2022 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-35268672

RESUMO

Aiming at constructing photoresponsive spin crossover (SCO) behavior, herein we designed a new ligand Abtz (Abtz = (E)-N-(4-((E)-phenyldiazenyl)phenyl)-1-(thiazol-4-yl)methanimine) which was decorated by a photochromic azobenzene group. Based on this photochromic ligand, a mononuclear Fe(II) SCO molecule [Fe(Abtz)3](BF4)2·(EAC)2 (1, EAC = ethyl acetate) was successfully synthesized and showed a complete one-step SCO behavior. Under continuous UV light and blue-light exposure, the cis-trans photoisomerization of both ligand Abtz and compound 1 in the liquid phase was confirmed through UV-Vis spectra. Moreover, the 1H-NMR spectra of Abtz reveal a trans-cis conversion ratio of 37%. Although the UV-Vis spectra reveal the photochromic behavior for 1 in the solution phase, the SCO behavior in the liquid state is absent according to the variable-temperature Evans method, suggesting the possible decomposition. Moreover, in the solid state, the cis-trans photoisomerization of both Abtz and 1 was not observed, due to the steric hindrance.

11.
Dalton Trans ; 51(13): 5195-5202, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35274652

RESUMO

Due to the small differences in the chemical properties of facial (fac) and meridional (mer) stereoisomers, selective synthesis of one of the isomers is challenging, especially for lanthanide complexes. By using a flexible bidentate phosphine oxide ligand, we managed to isolate three stereoisomeric 2D and 3D coordination polymers, in which six-coordinate Dy(III) ions possess fac- or mer-Cl3O3 coordination environments. Structural studies indicate that the stereochemistry differences result from their various supramolecular interactions (e.g., hydrogen bonding and π⋯π stacking). Magnetic property measurements reveal the different static and dynamic magnetic behaviours of the three stereoisomers. Ab initio CASSCF calculations were then performed which indicated that their distinct magnetic behaviours arise from their fac/mer configurations. Compared to fac-Dy(III), mer-Dy(III) possesses more axial ground-state KDs and higher first excited KDs.


Assuntos
Disprósio , Elementos da Série dos Lantanídeos , Cristalografia por Raios X , Disprósio/química , Elementos da Série dos Lantanídeos/química , Polímeros/química , Estereoisomerismo
12.
Curr Oncol ; 28(4): 2326-2336, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34202466

RESUMO

Liquid biopsy through the detection of circulating tumor DNA (ctDNA) has potential advantages in cancer monitoring and prediction. However, most previous studies in this area were performed with a few hotspot genes, single time point detection, or insufficient sequencing depth. In this study, we performed targeted next-generation sequencing (NGS) with a customized panel in metastatic breast cancer (MBC) patients. Fifty-four plasma samples were taken before chemotherapy and after the third course of treatment for detection and analysis. Paired lymphocytes were also included to eliminate clonal hematopoiesis (CH)-related alternatives. A total of 1182 nonsynonymous mutations in 419 genes were identified. More ctDNA mutations were detected in patients with tumors > 3 cm (p = 0.035) and HER2(-) patients (p = 0.029). For a single gene, the distribution of ctDNA mutations was also correlated with clinical characteristics. Multivariate regression analysis revealed that HER2 status was significantly associated with mutation burden (OR 0.02, 95% CI 0-0.62, p = 0.025). The profiles of ctDNA mutations exhibited marked discrepancies between two time points, and baseline ctDNA was more sensitive and specific than that after chemotherapy. Finally, elevated ctDNA mutation level was positively correlated with poor survival (p < 0.001). Mutations in ctDNA could serve as a potential biomarker for the evaluation, prediction, and clinical management guidance of MBC patients with chemotherapy.


Assuntos
Neoplasias da Mama , DNA Tumoral Circulante , Biomarcadores Tumorais/genética , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , DNA Tumoral Circulante/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação
13.
Chem Asian J ; 16(8): 931-936, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33619903

RESUMO

Materials combining proton conductivity and magnetism have attracted great attention in recent years due to their intriguing application in sensors and fuel cells. Herein a two-dimensional metal-organic framework, [Cu(atz)2 (H2 O)2 ]⋅H2 O (1) (Hatz=5-aminotetrazole), has been obtained in a green synthesis method. The single-crystal structure revealed that the atz- ligands as linkers coordinate with copper ions to sql networks, between which water molecules are immobilized through hydrogen bonds. The resulting complex 1 exhibits a high proton conductivity of 1.11×10-4 and 6.19×10-4  S cm-1 at room temperature and 333 K, respectively, under 98% RH with an activation energy of 0.56 eV. Upon dehydration, the proton conductivity of 1_dg drops by an order of magnitude. Furthermore, the magnetic behavior changes from long-range ferrimagnetic ordering of 1 to canted antiferromagnetic behaviour of 1_dg.

14.
Psychol Health Med ; 25(8): 980-988, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31967487

RESUMO

Few studies have concentrated on the prevalence and related factors of depression and falls among the elderly living in rural communities of Guangzhou. A total of 335 participants aged ≥60 years were recruited by simple random sampling method. A structural equation model was applied to determine interrelationships between depression, falls and other variables. As high as 27.5% and 23.3% participants had reported depressive symptoms and falls, respectively. The path analysis showed the total effect (ß = -0.58) of depression on quality of life (QOL) consisted of a direct effect (ß = -0.51) and an indirect effect (ß = -0.07), which was mediated by family function and number of falls, and the R2 was 0.36. The model fit indices were χ2/df = 1.096, P > 0.05, Root Mean Square Error of Approximation (RMSEA) = 0.017, Tucker-Lewis Index (TLI) = 0.998 and Comparative Fit Index (CFI) = 0.999. Depression and falls were prevalent among the elderly living in rural communities of Guangzhou city. Pay attention to strengthen family function and prevent falls may prevent depression and improve the QOL among the elderly.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Depressão/epidemiologia , População Rural/estatística & dados numéricos , Idoso , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida
15.
Psychol Health Med ; 25(6): 666-674, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31259609

RESUMO

The purpose of this study was to explore levels of organizational commitment, job satisfaction and work engagement among community health-care workers in China, and to examine spatial relationships of variables. Data were collected by Organizational Commitment Scale, Job Satisfaction Scale and Utrecht Work Engagement Scale from 1404 community health-care workers in Guangzhou and Shenzhen cities. Structural equation model was used to analyze relationships among three variables. Medium levels of organizational commitment, job satisfaction and work engagement were found among community health-care workers. Organizational commitment was positively correlated to work engagement (r = 0.564) and job satisfaction (r = 0.550). The path analysis indicated that total effect (ß = 0.598) of organizational commitment on job satisfaction (R2 = 0.52) consisted of a direct effect (ß = 0.264) and an indirect effect (ß = 0.334), which was mediated positively by work engagement. Improvement in work engagement may lead to higher level of job satisfaction and organizational commitment.


Assuntos
Pessoal de Saúde , Satisfação no Emprego , Lealdade ao Trabalho , Engajamento no Trabalho , Adulto , China , Estudos Transversais , Feminino , Clínicos Gerais , Humanos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros , Inquéritos e Questionários , Adulto Jovem
16.
Inorg Chem ; 58(24): 16346-16353, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31789516

RESUMO

Hybrid halide perovskites are emerging semiconducting materials with a diverse set of remarkable optoelectronic properties. Besides the widely studied lead halide perovskites, Pb-free metal halides such as Bi- and Sb-containing hybrid organic-inorganic materials have shown potential as semiconductors and have been deemed candidates for optoelectronic devices. Here, we report a series of 1D Sb/Bi-based organic-inorganic hybrid alloys: [4ApyH]SbxBi1-xIyBr4-y, where 4ApyH stands for the 4-aminopyridine cations. These compounds are assembled by edge-sharing octahedral [MX6] units stabilizing 1D chains with organic cations filled in between. The crystallographic data of eight selected complexes show that [4ApyH]SbxBi1-xIyBr4-y has at least five phases (space group) with the difference metal and halogen content: Pbca ([4ApyH]BiI4), Pca21 ([4ApyH]Sb0.5Bi0.5I4), P21/c ([4ApyH]SbI4 (100 K), [4ApyH]BiI2Br2, [4ApyH]BiBr4, and [4ApyH]SbBr4 (100 K)), I2/a ([4ApyH]Sb0.5Bi0.5I2Br2and [4ApyH]SbI2Br2), and C2/c ([4ApyH]SbI4 (298 K) and [4ApyH]SbBr4 (298 K)). Powder X-ray diffraction shows that the phase of the sample changes with a change of the metal and halogen ratios, and the change law accords with Vegard's law. The optical band gaps are heavily affected by the metal and halide contents, ranging from 1.94 eV for [4ApyH]BiI4 to 2.73 eV for [4ApyH]SbBr4. When Sb substitutes for Bi to form an alloy, the band gap increases from 1.94 for [4ApyH]BiI4 to 1.67 eV for [4ApyH]SbI4, from 2.13 eV for [4ApyH]BiI2Br2 to 2.41 eV for [4ApyH]SbI2Br2, and from 2.55 eV for [4ApyH]BiBr4 to 2.73 eV for [4ApyH]SbBr4. The conductivity of [4ApyH]SbxBi1-xI4 increased from ∼1.00 × 10-15 to 2.14 × 10-8 S cm-1 with an increase of the Sb content. Solution-deposited thin films of the nine complexes show the same (110) orientation, displaying a parallel growth orientation with respect to the substrate. The devices of [4ApyH]Sb0.8Bi0.2I4 and [4ApyH]SbI4 demonstrated stable open-circuit photovoltages of 0.55 and 0.44 V, steady-state short-circuit photocurrent densities of 1.52 and 1.81 mA cm-2, and light-to-electrical energy conversion efficiencies of 0.29% and 0.30%, respectively.

17.
Inorg Chem ; 58(16): 10694-10703, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31390195

RESUMO

The reactions of chiral ligand (R)/(S)-1,1'-binaphthyl-2,2'-diyl phosphate (R-HL/S-HL) and ErCl3·6H2O afford two pairs of di- and tetranuclear enantiomers [Er2(R/S-L)4(EtOH)6]Cl2·6.5EtOH (R-1, S-1) and [Er4(PO4)(R/S-L)8(EtOH)3(H2O)]2Cl(OH)·15EtOH·11H2O (R-2, S-2). The nuclearity of these complexes is controllable and depends on the reaction temperature with a template effect. Their chirality was evidenced by circular dichroism (CD) spectra. R-1 exhibits two magnetic relaxation pathways under a zero field, with an apparent barrier of 40 K. Ab initio calculations revealed a ferromagnetic dipolar interaction between these two Er(III) ions, the equatorial nature of the ligand field, and the probable origin of the two relaxations.

18.
Dalton Trans ; 48(34): 12888-12894, 2019 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-31389455

RESUMO

The structural information of a material in both the solid state and solution state is essential to the in-depth understanding of the properties of inorganic-organic hybrid materials. A one-dimensional (1D) lead bromide formulated as [H][NH3(CH2)2SS(CH2)2NH3][H2O][PbBr5] (1) could be converted into a new two-dimensional (2D) complex, [NH3(CH2)2SS(CH2)2NH3][PbBr4] (2), by soaking the crystals in water. The isolated 2D compound showed single-layer lead-halide perovskite structures. Electrospray ionization mass spectrometry (ESI-MS) analyses of the reaction solution revealed that the [PbBr3]- fragments are initially formed from the rapid decomposition of the 1D [PbBr5]3- chains and subsequently reassemble into 2D [PbBr4]2- layers, which was verified by powder X-ray diffraction (PXRD) and microcalorimetry. Because of the decomposition and reassembly process, complex 1 could be used as a precursor to synthesize M2+-doped 2D lead bromide perovskites, namely, Mn@2, Ni@2 and Cd@2. In addition, preliminary tests indicated that complex 2 exhibited a lower optical band gap (3.25 eV) and higher electrical conductivity (3.2 × 10-11 S cm-1) than complex 1 (3.38 eV, 5.4 × 10-12 S cm-1).

19.
Chem Asian J ; 14(9): 1467-1471, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30865374

RESUMO

Two isostructural mononuclear CoII complexes, [Co(xantpo)(NCE)2 ] (E=S (1) and O (2); xantpo=9,9-dimethyl-4,5-bis(diphenylphosphoryl) xanthene), supported by a bidentate phosphine oxide ligand are reported. The cobalt complexes exhibit characteristic tetrahedral structures coordinated with two oxygen and two nitrogen atoms. Magnetic property measurements show their similar static magnetic behaviours but very different dynamic magnetic behaviours. Both complexes show field-induced slow magnetic relaxation behaviours, but the relaxation of 2 is much slower than that of 1. Fittings to the magnetic data and ab initio CASSCF calculations reveal significant changes in the zero field splitting (ZFS) parameters (D and E), which can be attributed to the small geometrical changes of the Co ions and the different ligand field strength of the two terminal ligands.

20.
Clin Exp Hypertens ; 41(4): 373-380, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30095294

RESUMO

OBJECTIVE: This study aimed to investigate the most notable obesity index and its optimal cut-off point of hypertension in different age groups stratified by sexes among community residents in southern China. METHODS: In this cross-sectional study, 620 men and 631 women aged 18-59 years were enrolled. The independent-samples t-test and chi-square test were conducted to analyze continuous and categorical variables, respectively. Multivariate logistic regression analysis and receiver operating characteristic (ROC) curve analysis assessed the association between the obesity indices and hypertension risk. RESULTS: Waist-stature ratio (WSR) and waist-hip ratio (WHR) were the most notable risk factors for hypertension in young men and women, respectively. The odds ratios (ORs) of hypertension risk increased with per standard deviation (SD) in WSR and WHR (WSR: OR = 2.877, 95% confidence interval [CI] = 1.602 to 5.167; WHR: OR = 10.683, 95%CI = 2.179 to 52.376). In the middle-aged group of both sexes, body mass index (BMI) was the most distinctive risk factor for hypertension, the ORs of hypertension risk increased with per SD in BMI (men: OR = 2.297, 95%CI = 1.683 to 3.136; women: OR = 1.810, 95%CI = 1.338 to 2.450). ROC curve analysis demonstrated WSR and PI were better indicators than other indices among young men, and WSR was the best marker among young women. However, BMI and WC were the most sensitive markers in middle-aged men and women, respectively. CONCLUSIONS: In this Chinese population, the association of obesity indices and hypertension is inconsistent in different age groups and sexes. It is important to choose appropriate indicators for specific groups of people.


Assuntos
Tamanho Corporal , Hipertensão/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Estatura , Índice de Massa Corporal , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco , Fatores Sexuais , Circunferência da Cintura , Relação Cintura-Quadril , Adulto Jovem
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