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1.
Inorg Chem ; 62(15): 6189-6195, 2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37014228

RESUMO

Since the switchable spontaneous polarization of ferroelectric materials endows it with many useful properties such as a large pyroelectric coefficient, switchable spontaneous polarization, and semiconductor, it has a wide range of application prospects, and the research of high-performance molecular ferroelectric materials has become a hot spot. We obtained a 0D organic-inorganic hybrid ferroelectric [(CH3)3NCH2CH2CH3]2FeCl4 (1) with well-defined ferroelectric domains and excellent domain inversion and exhibited a relatively large spontaneous polarization (Ps = 9 µC/m-2) and a Curie temperature (Tc) of 394 K. Furthermore, compound 1 belongs to the non-centrosymmetrical space group Cmc21 and has a strong second-harmonic generation signal. Interestingly, we also performed magnetic tests on 1, which confirmed that it is a magnetic material. This work provides clues for exploring the application of high-performance molecular ferroelectric materials in future multifunctional smart devices.

2.
Exp Gerontol ; 175: 112148, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36931451

RESUMO

BACKGROUND AND PURPOSE: Although leisure-time physical activity (PA) has established health benefits in older adults, it is equivocal if exercising in environments with high levels of PM2.5 concentrations is equally beneficial for them. To explore the independent and joint associations of ambient PM2.5 and PA with all-cause mortality among adults aged 60 or older and to assess the modifying effect of age (60-74 years vs. 75+ years) on the joint associations. METHODS: A prospective cohort study based on the MJ Cohort repeat examinations (2005-2016) and the Taiwan Air Quality Monitoring Network and death registry linkages (2005-2022). We included MJ Cohort participants aged 60 or more at baseline who attended the health check-ups at least twice (n = 21,760). Metabolic equivalent hours per week (MET-h/week) of leisure-time PA were computed. Multivariable adjusted associations were examined using time-varying Cox proportional hazard models. RESULTS: There were 3539 all-cause deaths over a mean follow-up of 12.81 (SD = 3.67) years. Ambient PM2.5 and physical inactivity are both independently associated with all-cause mortality. The joint associations of PA and PM2.5 concentrations with all-cause mortality differed in the young-old (60-74 years) and the older-old (75+ years) (P for interaction = 0.01); Higher levels of long-term PM2.5 exposures (≥25 µg/m3) had little influence on the associations between PA and mortality in the young-old (HR = 0.68 (0.56-0.83) and HR = 0.72 (0.59-0.88) for participants with 7.5-<15 and 15+ MET-h/week respectively) but eliminated associations between exposure and outcome in the older-old (HR = 0.91 (0.69-01.21) and HR = 1.02 (0.76-1.38) for participants with 7.5-<15 and 15+ MET-h/week). CONCLUSION: Long-term exposures to higher PM2.5 concentrations may eliminate the beneficial associations of PA with all-cause mortality among adults aged 75 and over.


Assuntos
Poluentes Atmosféricos , Material Particulado , Humanos , Idoso , Material Particulado/efeitos adversos , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Estudos Prospectivos , Exercício Físico , Atividades de Lazer , Exposição Ambiental/análise
3.
Cancer Causes Control ; 20(1): 57-65, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18752033

RESUMO

OBJECTIVE: This study investigated the association between green tea consumption and leukemia. METHODS: A total of 252 cases (90.3% response) and 637 controls (53.4% response) were enrolled. Controls were matched for cases on age and gender. Information was collected on participants' living habits, including tea consumption. Green tea was used as a standard to estimate the total amount of individual catechin consumption. We stratified individual consumption of catechins into four levels. Conditional logistic regression models were fit to subjects aged 0-15 and 16-29 years to evaluate separate associations between leukemia and catechin consumption. RESULTS: A significant inverse association between green tea consumption and leukemia risk was found in individuals aged 16-29 years, whereas no significant association was found in the younger age groups. For the older group with higher amounts of tea consumption (>550 units of catechins), the adjusted odds ratio (OR) compared with the group without tea consumption was 0.47 [95% confidence interval (CI) = 0.23-0.97]. After we adjusted for smoking status and medical irradiation exposure, the overall OR for all participants was 0.49 (95% CI = 0.27-0.91), indicating an inverse relation between large amounts of catechins and leukemia. CONCLUSION: Drinking sufficient amounts of tea, especially green tea, which contains more catechins than oolong tea and black tea, may reduce the risk of leukemia.


Assuntos
Leucemia/epidemiologia , Chá , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fatores de Risco , Taiwan
4.
Zhongguo Zhong Yao Za Zhi ; 30(7): 551-4, 2005 Apr.
Artigo em Zh | MEDLINE | ID: mdl-16011107

RESUMO

OBJECTIVE: To explore the therapeutic effects and mechanisms of Zhubi capsule on adjuvant arthritis (AA) in rats. METHOD: The model of rat was induced by intradermal injection of CFA. The perimeter of ankle joint was measured at different time points. Con A-induced splencyte proliferation was examined by MIT assay and the expression of IL-1, IL-6 in synovium was determined by immunohistochemical method. RESULT: After the preventive administration of Zhubi capsule (5.2, 2.6, 1.3 g x kg x d(-1), x 25 d), it was found that Zhubi capsule significantly inhibited the primary and secondary ankle joint swelling. The increased Con A-induced splencyte proliferation reaction and the activated IL1, IL-6 expression of AA rat were suppressed by the treatment with Zhubi capsule. CONCLUSION: Zhubi capsule has a therapeutic effect on AA rats, and its mechanism is related to the immunoregulative function.


Assuntos
Articulação do Tornozelo/patologia , Artrite Experimental , Medicamentos de Ervas Chinesas/farmacologia , Interleucina-1/metabolismo , Materia Medica/farmacologia , Animais , Artrite Experimental/metabolismo , Artrite Experimental/patologia , Cápsulas , Proliferação de Células/efeitos dos fármacos , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/administração & dosagem , Interleucina-6/metabolismo , Masculino , Materia Medica/administração & dosagem , Fluidez de Membrana/efeitos dos fármacos , Plantas Medicinais/química , Ratos , Ratos Wistar , Baço/citologia , Membrana Sinovial/efeitos dos fármacos
7.
Am J Epidemiol ; 164(3): 200-7, 2006 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-16754633

RESUMO

The authors conducted a population-based, case-control study in Kaohsiung, southern Taiwan, Republic of China, to investigate the association between residential petrochemical exposure and leukemia risk among subjects 29 years of age and younger. Between November 1997 and June 2003, 171 cases and 410 controls matched for age and sex were recruited. Since assessment of petrochemical impacts depends on accurate exposure estimates, the authors developed a procedure using geographic information system tools to assign subjects' exposure. The resulting individual-level exposure estimates (the exposure opportunity score) are an integrated exposure measure that accounts for subjects' mobility, length of stay at each residence, distance to petrochemical plant(s), monthly prevailing wind direction, and multiple petrochemical pollution sources. Different conditional logistic regression models were fitted for subjects aged 0-19 and 20-29 years to evaluate separately childhood versus adulthood leukemia. No overall association was observed for the younger age group. However, residential petrochemical exposure was a significant risk factor for leukemia for the older age group. For one unit of increase in the log-transformed exposure opportunity score, the adjusted odds ratio was 1.54 (95 percent confidence interval: 1.14, 2.09). This study illustrates the utility of geographic information system tools for providing refined exposure estimates for residential exposure to petrochemical pollution.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Exposição Ambiental/efeitos adversos , Sistemas de Informação Geográfica , Leucemia/epidemiologia , Petróleo/efeitos adversos , Adolescente , Adulto , Estudos de Casos e Controles , Indústria Química , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Leucemia/etiologia , Masculino , Dinâmica Populacional , Risco , Taiwan/epidemiologia , Vento
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