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1.
Sci Adv ; 10(21): eadn9959, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38787957

ABSTRACT

P-type Bi2-xSbxTe3 compounds are crucial for thermoelectric applications at room temperature, with Bi0.5Sb1.5Te3 demonstrating superior performance, attributed to its maximum density-of-states effective mass (m*). However, the underlying electronic origin remains obscure, impeding further performance optimization. Herein, we synthesized high-quality Bi2-xSbxTe3 (00 l) films and performed comprehensive angle-resolved photoemission spectroscopy (ARPES) measurements and band structure calculations to shed light on the electronic structures. ARPES results directly evidenced that the band convergence along the [Formula: see text]-[Formula: see text] direction contributes to the maximum m* of Bi0.5Sb1.5Te3. Moreover, strategic manipulation of intrinsic defects optimized the hole density of Bi0.5Sb1.5Te3, allowing the extra valence band along [Formula: see text]-[Formula: see text] to contribute to the electrical transport. The synergy of the above two aspects documented the electronic origins of the Bi0.5Sb1.5Te3's superior performance that resulted in an extraordinary power factor of ~5.5 milliwatts per meter per square kelvin. The study offers valuable guidance for further performance optimization of p-type Bi2-xSbxTe3.

2.
J Public Health (Oxf) ; 42(3): 656-658, 2020 Aug 18.
Article in English | MEDLINE | ID: mdl-32648578

ABSTRACT

An ongoing outbreak of coronavirus disease 2019 (COVID-19) has rapidly spread in the world, whereas asymptomatic carriers may also play a critical role in the pandemic. We report a familial cluster of COVID-19 caused by one family member before his onset of illness, indicating that it seems to be potentially infectious during the incubation period, even earlier than we expected. Close contact, especially in a small enclosed space, might be the cause of familial transmission. The unsynchronized changes in the clinical symptoms and COVID-19 nucleic acid were found in this case, so consecutive nucleic acid detection of pretty suspected cases was recommended. Family members, especially of whom the confirmed cases contacted with since one incubation period before onset rather than 2 days before onset, should be regarded as close contact and centrally isolated in case of asymptomatic infection already existed in the family.


Subject(s)
Asymptomatic Infections , Coronavirus Infections/transmission , Disease Outbreaks/statistics & numerical data , Disease Transmission, Infectious/statistics & numerical data , Pneumonia, Viral/transmission , Betacoronavirus , COVID-19 , China/epidemiology , Cluster Analysis , Family , Humans , Infectious Disease Incubation Period , SARS-CoV-2
3.
Chem Commun (Camb) ; 56(26): 3809-3812, 2020 Mar 31.
Article in English | MEDLINE | ID: mdl-32129778

ABSTRACT

The as-synthesized (TBA)8H5[Nd(SiW11O39)2] manifested high catalytic activity for cyanosilylation of ketones, and its catalytic activity could be improved further through rational design of the reaction micro-environment beyond the molecular level, and the corresponding mechanism has been systematically studied.

4.
Arch Gerontol Geriatr ; 86: 103965, 2020.
Article in English | MEDLINE | ID: mdl-31683176

ABSTRACT

BACKGROUND: Centenarians are the fastest growing population worldwide. However, this group has been less studied in developing countries. Contemporary centenarians in China have experienced many ups and downs due to historical reasons, which may have resulted in a population with different characteristics from those in other countries. This study aimed to investigate the current sociodemographic characteristics, health profiles, and social relationships of Chinese centenarians. METHODS: We conducted face-to-face surveys in April 2017 with centenarian residents in Suixi County, the first "International Healthy Longevity Area" in China. A total of 100 centenarians were involved, including 67 females and 33 males. Information for socioeconomic and demographics characteristics, quality of life (physical, cognitive, and psychological function), and social support and relationships was collected. Sex differences in each measure were examined. RESULTS: We find that good self-reported health, good life satisfaction, intact memory function, independence, and unsatisfied healthcare needs were reported by 24.4%, 45.9%, 31.6%, 46.3%, and 33.4% of the respondents respectively. Subjective symptoms among males were less prevalent (p < 0.05). There were no statistical significant sex differences in cognitive and psychological function. The major source of care provision has been family. Generally, the centenarians had intimate relationships within families but maintained distant relationships with friends and communities. CONCLUSION: Our results bring attention to family-based care to provide informal care, and health education to promote healthy behaviors and healthcare utilization, for the oldest-old in China. The findings also imply a crucial role of good relationships with family in exceptional longevity.


Subject(s)
Asian People/statistics & numerical data , Interpersonal Relations , Longevity , Quality of Life/psychology , Social Support , Aged, 80 and over , China , Family , Female , Health Behavior , Health Status , Humans , Male , Self Report , Surveys and Questionnaires
5.
Molecules ; 24(4)2019 Feb 22.
Article in English | MEDLINE | ID: mdl-30813387

ABSTRACT

Six new hybrids based on ß-[Mo8O26]4- polyoxometalates, [Ni(H2biim)3]2[ß-Mo8O26]•8DMF(1); (DMA)2[M(H2biim)2(H2O)2][ß-Mo8O26]•4DMF (M = Ni (2), Co (3)), DMA = dimethyl-ammonium, H2biim=2,2'-biimidazole); [M(H2biim)(DMF)3]2[ß-Mo8O26]•2DMF (M = Zn (4), Cu (5)); [(DMA)2[Cu(DMF)4][ß-Mo8O26]•2DMF]n (6), have been successfully synthesized and characterized. Compounds 2⁻5 show favorable capacity to adsorb methylene blue (MB) at room temperature, and they can selectively capture MB molecules from binary-mixture solutions of MB/MO (MO = Methyl Orange), or MB/RhB (RhB = Rhodamine B). Compound 3 can uptake up to 521.7 mg g-1 MB cationic dyes rapidly, which perform the maximum adsorption in an hour among the reported materials as far as we know. The compounds are stable and still work very efficiently after three cycles. For compound 3, the preliminary adsorption mechanism studies indicated that the adsorption is an ion exchange process and the adsorption behavior of polyoxometalate-complex can be benefited from additional exchangeable protons in the complex cations.


Subject(s)
Imidazoles/chemistry , Tungsten Compounds/chemistry , Water Pollutants, Chemical/chemistry , Fluorescent Dyes/chemistry , Hydrogen-Ion Concentration , Kinetics , Methylene Blue/chemistry , Molecular Structure , Nanotechnology , Rhodamines/chemistry , Temperature
6.
Zhonghua Nei Ke Za Zhi ; 52(6): 494-7, 2013 Jun.
Article in Chinese | MEDLINE | ID: mdl-24059997

ABSTRACT

OBJECTIVE: To investigate the congenital heart disease (CHD) prevalence of students in Liangshan prefecture in Sichuan province, and to explore the risk factors of CHD. METHODS: Stratified cluster sampling was conducted in collecting demographic data. Heart auscultation was used to screening the CHD, and colour Doppler flow imaging was used to diagnose the CHD. RESULTS: A total of 10,021 student were collected in this study. About 19.74% of total cases had cardiac murmur. Sixty-eight students were diagnosed as CHD through colour Doppler flow imaging, accounting for 0.68%. In addition, the top three ranks of CHD were atrial septal defect, patent ductus arteriosus, interventricular septal defect. Our study also found that per capita income of CHD families was lower than non-CHD families, meanwhile, the CHD prevalence of Yi nationality was higher than other nationalities. There was no statistical significance in age, gender, height, weight, body mass index, head circumference, waist circumference between different types of CHD. CONCLUSIONS: The CHD prevalence of students in Liangshan prefecture has been in a high level in China; therefore we need pay more attention on screening for the CHD.


Subject(s)
Heart Defects, Congenital/epidemiology , Adolescent , Child , China/epidemiology , Female , Humans , Male , Prevalence , Risk Factors , Students
7.
Food Chem Toxicol ; 50(7): 2417-23, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22565279

ABSTRACT

Anti-benzo[a]pyrene-7,8-diol-9,10-epoxide (BPDE) is a ubiquitous environmental pollutant contained in tobacco smoke, automobile exhausts and barbecued foods. The carcinogenicity of BPDE on animals has been well characterized, whereas its apoptotic effect is not well defined. A recent study has shown that BPDE-mediated apoptotic pathway has varying specificity across different cell lines. Squamous cell carcinoma (SCC) arises from bronchiolar epithelium cells, therefore, we set out to investigate the pulmonary toxicity and apoptotic effect of BPDE in human bronchiolar epithelium cells (16HBE). Our results show BPDE induces mitochondrial-mediated apoptosis in a dose-dependent manner in 16HBE cells. The cleavage of caspase-3,-9 and release of Cytochrome c (cyt c) was regulated during apoptotic stimulation. However, the opening of mitochondria permeability transition pore (mPTP) has not been detected. Furthermore, our data also indicate that the formation of reactive oxygen species (ROS), decline of mitochondrial membrane potential (ΔΨ(m)), increasing p53 and decreasing c-Myc levels play important roles in response to BPDE toxicity. In conclusion, these results suggest that BPDE-mediated apoptosis occurs via caspase-9 dependent mitochondria pathway associated with ROS formation, loss of ΔΨ(m), up-regulation of p53 and down-regulation of c-Myc, but independent of the opening of mPTP in 16HBE cells.


Subject(s)
7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide/pharmacology , Apoptosis/drug effects , Bronchioles/drug effects , Mitochondria/drug effects , Blotting, Western , Bronchioles/cytology , Cell Line , Cytochromes c/metabolism , Dose-Response Relationship, Drug , Humans
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