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1.
Inorg Chem ; 62(11): 4672-4679, 2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36883521

ABSTRACT

Metal-organic frameworks (MOFs) have attracted noticeable attention as promising candidates for electrochemical energy storage. However, the lack of electrical conductivity and the weak stability of most MOFs result in poor electrochemical performances. Here, a tetrathiafulvalene (TTF)-based complex, formulated as [(CuCN)2(TTF(py)4)] (1) (TTF-(py)4 = tetra(4-pyridyl)-TTF), is assembled by in situ generation of coordinated CN- from a nontoxic source. Single-crystal X-ray diffraction analysis reveals that compound 1 possesses a two-dimensional layered planar structure, which is further stacked in parallel to form a three-dimensional supramolecular framework. The planar coordination environment of 1 is the first example of a TTF-based MOF. Attributed to the unique structure and redox TTF ligand, the electrical conductivity of 1 is significantly increased by 5 orders of magnitude upon iodine treatment. The iodine-treated 1 (1-ox) electrode displays typical battery-type behavior through electrochemical characterizations. The supercapattery based on the 1-ox positrode and AC negatrode presents a high specific capacity of 266.5 C g-1 at a specific current of 1 A g-1 with a remarkable specific energy of 62.9 Wh kg-1 at a specific power of 1.1 kW kg-1. The excellent electrochemical performance of 1-ox is one of the best among those reported supercapatteries, demonstrating a new strategy for developing MOF-based electrode materials.

2.
ACS Appl Mater Interfaces ; 15(5): 6621-6630, 2023 Feb 08.
Article in English | MEDLINE | ID: mdl-36695585

ABSTRACT

Poor electrical conductivity and instability of metal-organic frameworks (MOFs) have limited their energy storage and conversion efficiency. In this work, we report the application of oxidatively doped tetrathiafulvalene (TTF)-based MOFs for high-performance electrodes in supercapatteries. Two isostructural MOFs, formulated as [M(py-TTF-py)(BPDC)]·2H2O (M = NiII (1), ZnII (2); py-TTF-py = 2,6-bis(4'-pyridyl)TTF; H2BPDC = biphenyl-4,4'-dicarboxylic acid), are crystallographically characterized. The structural analyses show that the two MOFs possess a three-dimensional 8-fold interpenetrating diamond-like topology, which is the first example for TTF-based dual-ligand MOFs. Upon iodine treatment, MOFs 1 and 2 are converted into oxidatively doped 1-ox and 2-ox with high crystallinity. The electrical conductivity of 1-ox and 2-ox is significantly increased by six∼seven orders of magnitude. Benefiting from the unique structure and the pronounced development of electrical conductivity, the specific capacities reach 833.2 and 828.3 C g-1 at a specific current of 1 A g-1 for 1-ox and 2-ox, respectively. When used as a battery-type positrode to assemble a supercapattery, the AC∥1-ox and AC∥2-ox (AC = activated carbon) present an energy density of 90.3 and 83.0 Wh kg-1 at a power density of 1.18 kW kg-1 and great cycling stability with 82% of original capacity and 92% columbic efficiency retention after 10,000 cycles. Ex situ characterization illustrates the ligand-dominated mechanism in the charge/discharge processes. The excellent electrochemical performances of 1-ox and 2-ox are rarely reported for supercapatteries, illustrating that the construction of unique highly dense and robust structures of MOFs followed by postsynthetic oxidative doping is an effective approach to fabricate MOF-based electrode materials.

3.
Inorg Chem ; 60(22): 17074-17082, 2021 Nov 15.
Article in English | MEDLINE | ID: mdl-34702033

ABSTRACT

Although pristine metal-organic framework (MOF) anodes for lithium-ion batteries (LIBs) show moderate activities and relatively stable cycling, the poor rate capability of the MOF anodes limited their applications in the development of a new generation of energy storage. Herein, the electric active CoII ion is selected to coordinate with redox-active S-rich tetrathiafulvalene (TTF) derivatives to create two TTF-Co-MOFs, formulated as [Co2(py-TTF-py)2(BDC)2]·2DMF·H2O (TTF-Co-MOF 1) and [Co2(py-TTF-py)2(BPDC)2]·3DMF·3H2O (TTF-Co-MOF 2), where py-TTF-py = 2,6-bis(4'-pyridyl)tetrathiafulvalene, H2BDC = terephthalic acid, H2BPDC = biphenyl-4,4'-dicarboxylic acid, and DMF = N,N-dimethylformamide. Crystallographic characterization indicated that the two MOFs possess similar 2-fold-interpenetrating 3D frameworks but with two different pore sizes. The pore-size-dependent performances of the TTF-Co-MOFs were explored to optimize the MOFs as the anode materials for LIBs. TTF-Co-MOF 1 presents a high reversible specific capacity of 1186.6 mAh g-1 at 200 mA g-1 after 287 cycles. The rate capability is greatly enhanced by the introduction of CoII into TTF-based MOFs with specific capacities of 1028.6 mAh g-1 at 5 A g-1 and 966.5 mAh g-1 at 10 A g-1. On the basis of the series analysis of theoretical calculations, electrochemical impedance spectroscopy, and crystal structures, it is found that the CoII metal centers play a bridging role in charge transport within the MOF framework, which is beneficial for the transportation of Li ions. The competitive performances of TTF-Co-MOF 1 are attributed to the synergistic effect of the CoII metal centers and S-rich TTF ligand as well as suitable porosity. The study shed some light for the fabrication of advanced energy storage devices through the rational design of MOF-based anode materials.

4.
BMJ Open ; 11(9): e049570, 2021 09 07.
Article in English | MEDLINE | ID: mdl-34493518

ABSTRACT

OBJECTIVES: Patient satisfaction is an important indicator of hospital healthcare quality. Little up-to-date information of patient satisfaction in China is available. This study attempts to gain a holistic understanding of patient satisfaction in China and identify the key antecedents of patient satisfaction. DESIGN: A cross-sectional national survey was conducted in 2018. SETTING: Hospitals in 27 provinces and 4 municipalities in 4 regions of China. PARTICIPANTS: A random sample of 15 699 patients who visited 1304 hospitals were surveyed, with around 500 from each of the 27 provinces and 4 municipalities. PRIMARY AND SECONDARY OUTCOME MEASURES: The Hospital Consumer Assessment of Healthcare Providers and Systems questionnaire was used to measure patients' overall satisfaction and willingness to recommend the hospital. RESULTS: We found significant variation in overall patient satisfaction but little variation in hospital recommendation across the four broad regions. Moreover, we examined determinants of patient satisfaction and their likelihood to recommend the hospital. The overall satisfaction for inpatients and outpatients is commonly influenced by communication with doctors (inpatient: ß=0.524, p<0.001; outpatient: ß=0.541, p<0.001), hospital cleanness (inpatient: ß=0.165, p<0.05; outpatient: ß=0.144, p<0.001) and acceptable charges (inpatient: ß=1.481, p<0.001; outpatient: ß=1.045, p<0.001). Both inpatients and outpatients are more likely to recommend the hospital if there are communication with doctors (inpatient: OR=1.743, p<0.001; outpatient: OR=1.647, p<0.001), acceptable charges (inpatient: OR=2.660, p<0.001; outpatient: OR=2.433, p<0.001). Outpatient satisfaction and hospital recommendation are also influenced by time spent with doctors (satisfaction: ß=0.301, p<0.001; recommend: OR=1.430, p<0.001) and waiting time (satisfaction: ß=-0.318, p<0.001; recommend: OR=0.844, p<0.001). CONCLUSIONS: There are regional differences of patient satisfaction in China. Patient satisfaction is influenced by a variety of hospital factors and province/municipality factors. The influencing factors of patient satisfaction may not motivate patients to recommend the hospital.


Subject(s)
Outpatients , Patient Satisfaction , China , Cross-Sectional Studies , Humans , Inpatients , Surveys and Questionnaires
5.
Inorg Chem ; 60(12): 9132-9140, 2021 Jun 21.
Article in English | MEDLINE | ID: mdl-34081433

ABSTRACT

Two dimensional (2D) hybrid perovskites have attracted a great deal of interest because of their appropriate photovoltaic efficiency and environmental stability. Although some 2D hybrid perovskites with sulfur-containing amines have been reported, the cation having the mercaptan group has not been well explored yet. In this work, cysteamine (Cya, HS(CH2)2NH2), a mercaptan-containing amine, was introduced into 2D hybrid perovskite. Two 2D lead iodides with different structures, (HCya)2PbI4 (1) and (HCya)7Pb4I15 (2), were isolated as a red low-temperature phase and a yellow high-temperature phase, respectively. X-ray single-crystal structural analysis showed that the red phase 1 is a single layered corner-shared perovskite and that the yellow phase 2 is a corner/edge-shared quasi-2D perovskite. A thermo-induced reversible 1 to 2 phase transition was found in this synthetic system. The configuration of HCya cation greatly influences the crystallization equilibrium, generating different structures of the lead halides. The single-crystal structure of 1 is discussed in comparison with that of (HAE)2PbI4 (AE = HO(CH2)2NH2), an analogue of 1. The different effects of OH and SH groups on the 2D frameworks are studied based on their hydrogen bonding properties. More remarkably, although the two perovskites have similar structures, the (HCya)2PbI4 (1) has an intrinsic water stability that is much more stable than (HAE)2PbI4, which should be attributed to the affinity of the SH group with lead on the surface of the lead halide.

6.
Dalton Trans ; 50(23): 8120-8126, 2021 Jun 15.
Article in English | MEDLINE | ID: mdl-34021298

ABSTRACT

Introducing electronically active organic components into lower dimensional metal halide compounds is an effective strategy to improve the electronic properties of hybrid metal halide materials. We have previously used this strategy to explore hybrid halides with tetrathiafulvalenes (TTFs) and a series of lead iodides and bismuth halides were isolated. The electronic properties were improved notably using this modification. In this work, we expand the study of TTF based main-group metal halides to double metal halides with mixed lead and copper transition metals. Two hybrid TTF-lead-cuprous iodides, formulated as [TTF]5[Pb2Cu2I10]·H2O (1) and [TTF]2[PbCu2I6] (2), and two monometal analogues of [TTF]2[Cu4I6]·H2O (3) and [TTF]2[Ag4I6] (4) were crystallographically characterized. The anion of 1 is a 0D cluster, while that of the others is a 1D chain structure. The anion structures of 1-4 are novel and are reported for the first time. The TTF moieties are stacked to form a 2D framework in 1 and 1D columns in 2-4. We found that the semiconductor properties of the hybrids are related to electron donation from an anion to a cation. The electronic state of the TTF cations is another significant factor that affects the electronic properties of the materials. More notably, this work proved that the conductivity and photoconductivity of the mixed metal iodides are superior to those of the monometal iodides.

7.
J Chromatogr A ; 1538: 67-74, 2018 Feb 23.
Article in English | MEDLINE | ID: mdl-29361282

ABSTRACT

A method for rapid quantitation of insect juvenile hormones (JH) and intermediates in the biosynthetic pathway, both in vitro and in vivo (hemolymph and whole body), has been developed using GC-MS/MS. This method is as simple as the radiochemical assay (RCA), the most commonly used method for measurement of JH biosynthesis in vitro, without need for further purification and derivatization, or radioactive precursors or ligands. It shows high sensitivity, accuracy and reproducibility. Linear responses were obtained the range of 1-800 ng/mL (approximately 4-3000 nM). Recovery efficiencies for farnesol, farnesal, methyl farnesoate and JH III were approximately 100% in vitro and over 90% in vivo, with excellent reproducibility at three different spike levels. Titer of JH III in the hemolymph was relatively low at day 0 (adult female emergence) (79.68 ±â€¯5.03 ng/mL) but increased to a maximum of 1717 ng/mL five days later. In whole body, JH III quantity reached a maximum on day 4 (845.5 ±â€¯87.9 ng/g) and day 5 (679.7 ±â€¯164.6 ng/g) and declined rapidly thereafter. It is in agreement with the hemolymph titer changes and biosynthetic rate of JH in vitro. Comparison with the results of inhibition of JH biosynthesis by two known inhibitors (allatostatin (AST) mimic H17 and pitavastatin) using RCA and GC-MS/MS, showed that there was little difference between the two methods In contrast to other methods, the present method with GC-MS/MS can be used to elucidate the mechanism of inhibition by inhibitors of JH biosynthesis without any derivatization and purification. This method is applicable to screening of JH inhibitors and the study of inhibitory mechanisms with high sensitivity and accurate quantification. It may also be useful for the determination of JH titer in other Arthropods.


Subject(s)
Biosynthetic Pathways/physiology , Chemistry Techniques, Analytical/methods , Cockroaches/chemistry , Entomology/methods , Gas Chromatography-Mass Spectrometry , Juvenile Hormones/analysis , Animals , Chemistry Techniques, Analytical/instrumentation , Cockroaches/growth & development , Farnesol/analogs & derivatives , Farnesol/analysis , Farnesol/isolation & purification , Fatty Acids, Unsaturated/analysis , Fatty Acids, Unsaturated/isolation & purification , Hemolymph/chemistry , Juvenile Hormones/chemistry , Reproducibility of Results , Sesquiterpenes/analysis , Sesquiterpenes/isolation & purification
8.
Article in English | MEDLINE | ID: mdl-28273867

ABSTRACT

This study aimed to assess the mortality risks for human infection with high (HPAI) and low (LPAI) pathogenicity avian influenza viruses. The HPAI case fatality rate (CFR) was far higher than the LPAI CFR [66.0% (293/444) vs. 68.75% (11/16) vs. 40.4% (265/656) vs. 0.0% (0/18) in the cases with H5N1, H5N6, H7N9, and H9N2 viruses, respectively; p < 0.001]. Similarly, the CFR of the index cases was greater than the secondary cases with H5N1 [100% (43/43) vs. 43.3% (42/97), p < 0.001]. Old age [22.5 vs. 17 years for H5N1, p = 0.018; 61 vs. 49 years for H7H9, p < 0.001], concurrent diseases [18.8% (15/80) vs. 8.33% (9/108) for H5N1, p = 0.046; 58.6% (156/266) vs. 34.8% (135/388) for H7H9, p < 0.001], delayed confirmation [13 vs. 6 days for H5N1, p < 0.001; 10 vs. 8 days for H7N9, p = 0.011] in the fatalities and survivors, were risk factors for deaths. With regard to the H5N1 clusters, exposure to poultry [67.4% (29/43) vs. 45.2% (19/42), p = 0.039] was the higher risk for the primary than the secondary deaths. In conclusion, old age, comorbidities, delayed confirmation, along with poultry exposure are the major risks contributing to fatal outcomes in human HPAI and LPAI infections.


Subject(s)
Influenza A Virus, H5N1 Subtype/pathogenicity , Influenza A Virus, H7N9 Subtype/pathogenicity , Influenza A Virus, H9N2 Subtype/pathogenicity , Influenza in Birds/virology , Influenza, Human/epidemiology , Influenza, Human/virology , Adolescent , Animals , Birds , Female , Humans , Incidence , Influenza in Birds/epidemiology , Influenza, Human/mortality , Male , Middle Aged , Risk Factors , Seasons , Virulence , Young Adult
9.
Chin Med J (Engl) ; 129(7): 814-8, 2016 Apr 05.
Article in English | MEDLINE | ID: mdl-26996477

ABSTRACT

BACKGROUND: Patient trust in physicians, which can be considered a collective good, is necessary for an effective health care system. However, there is a widespread concern that patient trust in physicians is declining under various threats to the physician-patient relationship worldwide. This article aimed to assess patient trust in physicians through a quantitative study in Shanghai, China, and to provide appropriate suggestions for improving the trust in China. METHODS: The data from a survey conducted in Zhongshan Hospital and Shanghai Tenth People's Hospital, which are two tertiary public hospitals in Shanghai, were used in this study. Patient trust in physicians was the dependent variable. Furthermore, a 10-item scale was used to precisely describe the dependent variable. The demographic characteristics were independent variables of trust in physicians. Binomial logistic regression was employed to analyze the factors associated with the dependent variable, which was divided into two categories on the basis of the responses (1: Strongly agree or agree and 0: Strongly disagree, disagree, or neutral). RESULTS: This study found that 67% of patients trusted or strongly trusted physicians. The mean score of patient trust in physicians was 35.4 from a total score of 50. Furthermore, patient trust in physicians was significantly correlated with the age, education level, annual income, and health insurance coverage of the patients. CONCLUSIONS: Patient trust in physicians in Shanghai, China is higher than previously reported. Furthermore, the most crucial reason for patient distrust in physicians is the information asymmetry between patients and physicians, which is a natural property of the physician-patient relationship, rather than the so-called for-profit characteristic of physicians or patients' excessive expectations.


Subject(s)
Physician-Patient Relations , Trust , Adolescent , Adult , Aged , China , Female , Humans , Logistic Models , Male , Middle Aged
10.
Zhonghua Shao Shang Za Zhi ; 28(6): 455-7, 2012 Dec.
Article in Chinese | MEDLINE | ID: mdl-23327915

ABSTRACT

This study analyzed the current situation and problems of two-way referral between wound healing department of general hospitals and community health service centers through stipulated interview with physicians in general hospitals and community health service centers, and patients visiting these organizations from March 2011 to April. It was found that the current two-way referral process for wound repair were facing a series of problems, including hospitals-transfer difficulty, incomplete two-way referral policy and undefined practice protocol, information-sharing obstacle between general hospitals and community health service centers. The critical countermeasures for overcoming these obstacles in two-way referral of wound ailments shall include construction of further linkage mechanism among all levels of hospitals, establishment of the drug-obtaining mechanism, establishment of an explicit two-way referral process of wound repair, and establishment of a database of diagnosis and treatment information of patients that can be accessed by doctors of different levels of hospitals, etc.


Subject(s)
Community-Institutional Relations , Hospitals, Special , Referral and Consultation , Community Health Planning , Humans , Wound Healing
11.
Chin Med J (Engl) ; 124(20): 3320-6, 2011 Oct.
Article in English | MEDLINE | ID: mdl-22088529

ABSTRACT

BACKGROUND: National Breast and Cervical Cancer Early Detection Program (NBCCEDP) has provided free or low-cost mammograms to low-income or no health insurance women in all of the states of the United States (US) since 1997. The objective of this study was to understand whether health insurance and annual household income impacted the mammography utilization since the implementation of NBCCEDP, in order to evaluate how the implementation of NBCCEDP impacted mammography utilization among American women. METHODS: Data were from the database of Behavioral Risk Factor Surveillance System (BRFSS) of the CDC in US. Mammography utilization was measured by whether the American woman aged 40 to 64 years had the mammography within the last two years. The chi square test and multivariate Logistic regression were used to evaluate the associations between mammography utilization and health insurance, annual household income, and other factors for any given year. RESULTS: From 2000 to 2008, the rate of mammography utilization among participants had a steady decrease on the whole from 86.7% to 83.8%. The results showed that the mammography utilization correlated significantly with health insurance and annual household income for any given year. The results also showed that compared with participants who were uninsured, those who were insured had a greater times higher rate of mammography in 2008 than any other year from 2000 to 2008, and compared with participants whose annual household income was below $15 000, those whose annual household income was above $50 000 had a greater times higher rate of mammography in 2008 than in 2004 and 2006. CONCLUSIONS: Health insurance and annual household income impacted the mammography utilization for any given year from 2000 to 2008, and the implementation of NBCCEDP has not achieved its original goal on breast cancer screening.


Subject(s)
Income , Insurance, Health , Mammography/statistics & numerical data , Adult , Female , Humans , Middle Aged , United States
12.
Chin Med J (Engl) ; 124(15): 2328-34, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21933564

ABSTRACT

BACKGROUND: According to the regulations of the Chinese and Shanghai governments, migrant workers employed in Shanghai should all be entitled to Shanghai Migrant Worker Hospitalization Insurance (SMWHI) without premium and the vast majority should also have the New Rural Cooperative Medical System (NRCMS). This study aimed to examine the status of the coverage and utilization of health insurance among migrant workers employed in Shanghai. METHODS: Quantitative and qualitative research methods were employed in the study. A survey of 1020 migrant workers employed in Shanghai was conducted in 2010 with a structured questionnaire. Focus group discussions were held with respondents who were unable to maintain health insurance coverage through NRCMS or SMWHI. In-depth interviews were held with village heads and employers of the migrant workers, migrant workers who were hospitalized within the last year, and various individuals employed by the insurance agencies. RESULTS: The study found that 72.9% and 36.5% of migrant workers were covered by NRCMS or SMWHI, respectively, while 16.7% of them had no health insurance. The coverage by NRCMS among migrant workers correlated significantly with education level and workplace, while the coverage by SMWHI correlated significantly with the length of employment in Shanghai and workplace. The qualitative results confirmed that migrant workers were the main group who were not covered by NRCMS, and the coverage by SMWHI was completely dependent upon the employers of the migrant worker. The results also showed that health insurance utilization among migrant workers was strongly limited by hospital location. CONCLUSIONS: We observed that the status of health insurance among migrant workers was not accordant with theory, and that Chinese health insurance policy should be further reformed in order to realize full coverage and equal utilization of health insurance among migrant workers in China.


Subject(s)
Insurance Coverage/statistics & numerical data , Insurance, Health/statistics & numerical data , Transients and Migrants/statistics & numerical data , Adolescent , Adult , China , Female , Humans , Male , Young Adult
13.
Chin Med J (Engl) ; 124(6): 947-50, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21518609

ABSTRACT

This study is designed to serve as a reference for the establishment of health security systems for children's critical diseases. Through analysis of the operation of Shanghai Children Hospital Care Aid (SCHCA), this study explored the financing model and management of a children's critical disease healthcare system and analyzed the possibility of expanding this system to other areas. It is found that a premium as low as RMB 7 per capita per year under SCHCA can provide high-level security for children's critical diseases. With the good experience in Shanghai and based on the current basic medical insurance system for urban residents and the new rural cooperative medical scheme (NRCMS), it is necessary and feasible to build a health security system for children's critical diseases at the national level.


Subject(s)
Health Policy/economics , Health Policy/legislation & jurisprudence , Adolescent , Child , Child Welfare , Child, Preschool , China , Delivery of Health Care , Humans , Infant , Infant, Newborn
14.
J Med Virol ; 82(12): 1985-95, 2010 Dec.
Article in English | MEDLINE | ID: mdl-20981784

ABSTRACT

This paper described the epidemiology and controlling experiences of influenza H1N1 in Hangzhou in the past 1 year. A total of 2,078 cases confirmed by real-time quantitative PCR till March 31, 2010, were analyzed by SPSS 12.0 software. During the early pandemic stage, a patient must be tested for H1N1 nucleic acid once he/she had influenza-like symptoms with the epidemiological history in 7 days, and be diagnosed if it was positive. But in the pandemic peak, we made efforts to identify and save severe cases combined with pneumonia or hypoxemia or respiratory failure or septic shock or multiple organ dysfunctions and failure. In general, the prevalence was 2.77/100,000 (2,078/7,510,844); severity rate, 10.44% (217/2,078); fatality rate, 0.48% (10/2,078). The carrier and secondary attack rate were 9.52% (58/612) and 8.66% (53/612), respectively. About 50% of serious cases and 100% of deaths had the basic underlying diseases: cardiovascular diseases, 13.66% (25/217); chronic lung disease, 12.02% (22/217); pregnant, 7.1% (13/217). Of all cases aged from 1 month to 89 years, 52.99% (1,435/2,708) were in the 10-29 years, with most of them distributed in downtown area. The timeline showed two epidemic peaks occurred in September and November 2009, respectively. Furthermore, the hemagglutinin gene remained 99% identical with the American and vaccine strains, but only 70% with the 1947-2008 Chinese strains. In conclusion, Hangzhou pandemic influenza H1N1 was caused by the highly conserved virus, with low prevalence, transmission, and mortality, because we took efficient controlling methods.


Subject(s)
Hemagglutinin Glycoproteins, Influenza Virus/genetics , Influenza A Virus, H1N1 Subtype/isolation & purification , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Amino Acid Sequence , Child , Child, Preschool , China/epidemiology , Disease Outbreaks , Female , Humans , Infant , Influenza A Virus, H1N1 Subtype/genetics , Influenza, Human/complications , Influenza, Human/virology , Male , Middle Aged , Molecular Sequence Data , Pregnancy , Prevalence , Sequence Analysis, DNA , Young Adult
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