Search

2,6-bis(trimethylstannane)-4,8-bis(2-octyldecyloxy)benzo[1,2-b:4,5-b′]dithiophene coupled with 2,5-didecyloxy-1,4-dibromobenzene and 4,7-dibromo-5,6-dioctyloxy-2,1,3-benzothiadiazole using Stille-coupling polymerization to afford the non D-A type polymer P1 and D-A type polymer P2, respectively. Two polymers displayed excellent solubility in normal organic solvents, so series of chemical instrumental analysis, such as NMR, GPC and elemental analysis, were carried out to confirm the inner structure and composition of the polymers. Different structure types exerted great influence on polymer's optical, electrochemical and electrochromic properties. Compared with P1 film, the introduction of the strong electron-withdrawing group benzothiadiazole improved conjugate effect along the polymer backbone of P2, which caused the redshift of ultraviolet–visible absorption spectrum and significant reduction in energy band gap. In addition, electrochromic performance test results showed that the P1 polymer film can switch between the orange-yellow and gray, while P2 film changed from blue in the neutral state to light yellow in the oxidation state. Moreover, the optical contrasts and response times of the polymer films also showed great differences due to the different molecular structure types. Higher transmittance changes and less sensitivity to the step interval on optical contrast indicated the fast switching speed and the superior cycle stability of P2 film.

Two novel decyloxyphenylquinoxaline-based donor-acceptor (D-A) electroactive monomers bearing dialkoxythiophene as the donor unit are synthesized using Stille coupling reaction. The corresponding polymers, poly[2,3-bis(4-decyloxyphenyl)-5,8-bis(3,4-dimethoxylthiophen-2-yl)quinoxaline] (P1) and poly[2,3-bis(4-decyloxyphenyl)-5,8-bis(2,3-dihydrothieno[3,4-b][1,4]dioxin-5-yl)quinoxaline] (P2), are directly deposited onto the working electrode surface by electropolymerization. All materials were characterized by nuclear magnetic resonance (NMR), mass spectrometry (MS), scanning electron microscopy (SEM), cyclic voltammetry (CV), ultraviolet-visible absorption spectrometry (UV-Vis) and spectro-electrochemical measurements. Electrochemical studies demonstrate that both polymers are capable of showing both reasonable n- and p-doping processes, and advanced long-term switching stabilities. 3,4-Ethylenedioxythiophene substituted for 3,4-dimethoxythiophene as a donor unit, which enhances the conjugated double-bond character of the conducting polymer, thus leading to a lower electronic band-gap. Likewise, the neutral state color of the synthesized polymer tuned from blue to blue-green corresponding to the red shift of the maximum absorption wavelengths in the visible region. In addition, kinetics study of P1 revealed 42% (595 nm), 30% (839 nm) and 69% (1500 nm) transmittance changes (ΔT%), while P2 exhibited 32% (740 nm), 71% (2000 nm) at the dominant wavelengths. It was also observed that both films could switch quickly between the neutral state and oxidation state, with the response time less than 1 s both in visible and near infrared regions.

Lung cancer is a common disease with high mortality in China. Recent economic advances have led to improved medical capabilities, while costs associated with treating this disease have increased. Such change contributes to a commonly held belief that healthcare costs are out of control. However, few studies have examined this issue. Here, we use 34,678 hospitalization summary reports from 67 Guangxi hospitals (period 2013-2016) to document costs, temporal trends, and associated factors. Findings from this study are surprising in that they debunk the myth of uncontrolled healthcare costs. In addition, results and experiences from Guangxi are informative for other comparable regions.

t is of great importance to find ways to lubricate ZrO2ceramic. In this paper, a kind of ZrO2 matrix high temperature self-lubricating compositewith addition of CaF2 and graphite as lubricants was prepared by hot-pressing. It was found that the tribological properties of ZrO2(Y2O3)-CaF2-graphiteshow a good tribological behavior both at low temperature and high temperatures. The low friction coefficients of ZrO2 (Y2O3)-Mo-CaF2-graphite at high temperatures were due to the perfect lubricity of CaMoO4 which was formed on the worn surface at high temperatures.

Background The rising cost of healthcare is of great concern in China, as evidenced by the media features negative reports almost daily. However there are only a few studies from well-developed cities, like Beijing or Shanghai, and little is known about healthcare costs in rest of the country. In this study, we use hospitalization summary reports (HSRs) from admitted cardiovascular diseases patients in Guangxi hospitals during 2013-2016, and we investigate temporal trends of healthcare costs and associated factors. Methods By generalized additive model, we compute temporal trends of cost per stay (CPS), cost per day (CPD) and others. We then use generalized linear models to assess which factors associate with CPS and CPD. Findings Using a total of 760,000 HSRs, we find that CPS appears to be stabilized around $1040 until the middle of year 2015, before exhibiting a downward trend. Similarly, CPD exhibits similar stable pattern. Meanwhile, surgery-specific CPS showed an increase in year 2013-2014, and then stabilized. Drug costs account for over 1/3 of CPS, but they are gradually declining. Costs associated with physicians' and nurses' services represent less than 5% of CPS. We found that age, sex, marital status, occupation and payment methods are significantly associated with CPS or CPD. Interestingly, we found no association between patient ethnicity and these costs. However, we did find that minority patients use more secondary hospitals than Han patients. Interpretations Healthcare costs in Guangxi are stable, contrary to the rise portrayed by Chinese mass media. Several factors can be associated with healthcare costs, and these may be useful for developing evidence-based policies. In particular, there is a need to encourage more Han patients to seek care in primary and secondary hospitals.

Epidemiological studies have shown that human papillomavirus 58 (HPV 58) is found at a relatively high frequency in east Asia and some regions of Central and South America. To investigate the physical status of HPV 58 and analyse sequence variations of HPV 58 in cervical cancer patients, the HPV 58 genome in 37 HPV 58-positive cervical cancer specimens collected from China were investigated by a mapping analysis based on nested PCR and nucleotide sequencing. A pure integrated genome was found in 78.4 % (29/37) of specimens, which is much higher than that found in previous studies. Multiple disruptions were first found among the integrated HPV 58 genomes in 51.7 % (15/29) of specimens. Among the 7824 bp of the HPV 58 genome, 119 (1.52 %) nucleotide positions were found to be variable, and 45 of them lead to amino acid changes. Phylogenetic analyses, based on partial L1 sequences of 14 variants isolated in previous studies and this study, show that two main groups were observed in HPV 58 variants, the prototype or prototype-like group and the non-prototype-like group.