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Hypothermia (core temperature <36°C) during major surgeries could result in a number of adverse events such as surgical site infection, bleeding, and prolonged hospital stay. The incidence of intraoperative hypothermia was 44.3 percent in China in 2015, with only 10.7 percent of patients receiving effective hypothermia prevention measures during major surgeries. By systematically examining the adverse risks for patients using different warming measures (active and passive), our study discussed the potential of bringing the most effective one(s) into clinical guidelines.
Methods
Articles, ongoing trials and grey literatures were retrieved from PubMed, The Cochrane Library and Clinical Trials till February 2019. Bair HuggerTM (BH) was determined to be the reference group and all randomized controlled trials including BH were included. In the control group, we kept all possible warming measures. Adverse effect indicators were decided using scoping reviews and then applied in literature screening. Type (open/endoscopic) and length of surgery were included in sub-group analysis.
Results
A total of forty-two studies were included, with twenty-seven of them passive insulation measures and fifteen active measures. Compared with passive measures, BH had significant advantages, such as in surgical site infection (risk ratio [RR] = 0.13, 95% confidence interval [CI]: 0.05, 0.80), chills (RR = 0.37, 95% CI: 0.25, 0.54) and hospitalization stay (mean difference [MD]=−1.27d, 95% CI: -2.05, -0.48). Compared with active insulation measures, BH had no significant advantages. Patients with open or longer surgeries (≥2 hours) experienced higher risks.
Conclusions
Generally, an active warming system is more effective in lowering risks (e.g., hypothermia, surgical site infection, chills, length of stay) than passive ones, especially for patients going through non-endoscopic or longer surgeries. Among the active warming systems, BH does the same job as other active insulation measures. Given that the practice of peri-operative hypothermia prevention using active warming systems is not popular in China, the use of BH and other active insulation measures during major surgeries are recommended to improve the safety and potentially reduce the cost of treating those clinical adverse events.
Lead-free BaTiO3 (BT)-based multilayer ceramic capacitors (MLCCs) with the thickness of dielectric layers ~9 μm were successfully fabricated by tape-casting and screen-printing techniques. A single phase of the pseudo-cubic structure was revealed by X-ray diffraction. Backscattered images and energy-dispersive X-ray elemental mapping indicated the high quality of MLCCs without observation of interaction, wrapping, or delamination. The relaxor state was confirmed by transmission electron microscopy and temperature-dependent permittivity. Impedance spectroscopy at various temperatures revealed the electrical heterogeneous response for MLCCs with high-resistive electrical components. Improved energy storage performance was obtained by multilayering, comparing with the bulk ceramics. Enhanced recoverable energy density ~6.88 J/cm3 with high efficiency ~90% were realized under an electric field of 820 kV/cm, which is mainly attributed to the intrinsic high-resistivity and relaxor behavior. Furthermore, good temperature (20–85 °C) and frequency stabilities (0.5–50 Hz) were observed in the MLCCs, which are attractive for pulsed power applications.
We investigated high-resistivity cadmium zinc telluride (CdZnTe):In single crystals annealed in hydrogen to reveal the passivation effect of defects. An overall reduction in the concentration of defect levels induced by annealing was obviously observed by thermally stimulated current measurements. There is a large decrease by 56.51% in the concentration of secondly ionized Cd vacancies (T3) after hydrogenation. The concentration of firstly ionized Cd vacancies (T2) was a little bit lower (17.99%) in the hydrogenated CZT crystals. The formation of neutral InH complex and lower occupation of VCd by In dopant would result in a significant decrease (68.31%) in the trap density of ${\rm In}_{\rm Cd}^ +$ related shallow donor (T1) after hydrogenation. The bulk resistivity was calculated from I–V characteristic curves to be ~1.97 × 1010 Ωcm before annealing and ~1.78 × 1010 Ωcm after annealing. Hall measurements also reveal n-type conduction for the hydrogenated crystals. Electron mobility was fitted to be about 110 cm2/Vs before annealing and 488 cm2/Vs after annealing, demonstrating better carrier transport properties. Electron mobility-lifetime product could be fitted to be about 3.60 × 10−4 cm2/V before annealing and 5.45 × 10−4 cm2/V after annealing, demonstrating better detector performances.
The structural changes recent-onset posttraumatic stress disorder (PTSD) subjects were rarely investigated. This study was to compare temporal and causal relationships of structural changes in recent-onset PTSD with trauma-exposed control (TEC) subjects and non-TEC subjects.
Methods
T1-weighted magnetic resonance images of 27 PTSD, 33 TEC and 30 age- and sex-matched healthy control (HC) subjects were studied. The causal network of structural covariance was used to evaluate the causal relationships of structural changes in PTSD patients.
Results
Volumes of bilateral hippocampal and left lingual gyrus were significantly smaller in PTSD patients and TEC subjects than HC subjects. As symptom scores increase, reduction in gray matter volume began in the hippocampus and progressed to the frontal lobe, then to the temporal and occipital cortices (p < 0.05, false discovery rate corrected). The hippocampus might be the primary hub of the directional network and demonstrated positive causal effects on the frontal, temporal and occipital regions (p < 0.05, false discovery rate corrected). The frontal regions, which were identified to be transitional points, projected causal effects to the occipital lobe and temporal regions and received causal effects from the hippocampus (p < 0.05, false discovery rate corrected).
Conclusions
The results offer evidence of localized abnormalities in the bilateral hippocampus and remote abnormalities in multiple temporal and frontal regions in typhoon-exposed PTSD patients.
Fullerene dimers have attracted extensive attention due to their unique structures and fascinating properties. Here, fullerene dimer derivatives with four to six carbon atoms in the esters are designed and synthesized. The property differences that caused by the carbon number in the esters of the fullerene dimers are investigated by performing their electrochemical, optical, and photoelectric measurements. As the carbon atom numbers in the esters increase from four to five and six, the absorption intensities increase to 1.6- and 4.4-folds. The intensities of the fluorescence spectra increase to 1.8- and 5.2-folds. Their photocurrent increases to 2- and 7-folds under the irradiation of a 405-nm laser. The LUMO energy levels move downward slightly from −3.89 to −3.90 and −3.92 eV, respectively. Our results indicate that as the carbon number increases, the carbon chain lengths in the ester structures increase, very slight effects produced on the energy levels of the fullerene dimers, but strongly contribute to their chemical activities and thus the photoelectronic efficiencies.
A highly active catalyst of cerium–tungsten–titanium mixed oxide was synthesized by introducing Ce4+ and H2O2 in the base sample of Ce20W10Ti100Oz–Ce3+. As a consequence, the NH3-SCR activity of Ce20W10Ti100Oz–Ce3+ is significantly improved as the additives of Ce4+ and H2O2 enlarge the Brunauer–Emmett–Teller (BET) surface area by refining its pore size. Meanwhile, the introduction of Ce4+ increases the Lewis acid sites of Ce20W10Ti100Oz–Ce3+ and decreases its low-temperature Brønsted acid sites. The further addition of H2O2 improves the Brønsted acid sites and dispersion of cerium/tungsten species, and thereby enhances the concentrations of the adsorbed oxygen (Oα) and the adsorbed oxygen
$\lpar {\rm {O}^{\prime}}_{\rm \alpha} \rpar$
due to the activation of chemisorbed water on the surface of the catalyst. The addition of Ce4+ and H2O2 shows a synergistic promotional effect, which is due to the largest BET surface area and the highest concentrations of Oα or/and
${\rm {O}^{\prime}}_{\rm \alpha}$
. Ce20W10Ti100Oz–Ce3+:Ce4+ = 17.5:2.5 + H2O2 exhibits the highest catalytic activity compared with the conventional ones (Fig. 5).
To examine the associations between serum 25-hydroxyvitamin D (25(OH)D) levels and serum liver enzymes in a representative sample of US adults.
Design:
The cross-sectional study sample consisted of 24 229 adults with data on serum 25(OH)D levels and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and gamma-glutamyl transaminase (GGT) concentrations, in addition to data on other potential confounders. Multivariate logistic regression and linear regression were applied to assess the associations between serum 25(OH)D levels and ALT, AST, ALP and GGT concentrations.
Setting:
The National Health and Nutrition Examination Survey, 2001–2006.
Participants:
The cross-sectional study sample consisted of 24 229 adults.
Results:
We found a significant association between low serum 25(OH)D levels (<30 nmol/l) and ALP levels in all participants (OR 2·67; 95 % CI 1·98, 3·59; P < 0·001), a confirmed healthy population (OR 3·02; 95 % CI 2·25, 4·07; P < 0·001) and individuals with viral hepatitis (OR 2·87; 95 % CI 1·52, 5·44; P = 0·006) compared with those who had normal 25(OH)D levels (>50 nmol/l). Moreover, in both the logistic regression and linear regression, the associations between 25(OH)D levels and ALP levels were stronger in the subgroups with obesity. No association was present between ALT, AST or GGT levels and serum 25(OH)D levels in this population.
Conclusions:
The results of the present study provide epidemiological evidence that vitamin D deficiency is associated with liver ALP levels in humans. This finding suggests a potential adverse effect of low 25(OH)D levels on human liver function. However, the underlying mechanisms still need further investigation.
Data on average iodine requirements for the Chinese population are limited following implementation of long-term universal salt iodisation. We explored the minimum iodine requirements of young adults in China using a balance experiment and the ‘iodine overflow’ hypothesis proposed by our team. Sixty healthy young adults were enrolled to consume a sequential experimental diet containing low, medium and high levels of iodine (about 20, 40 and 60 μg/d, respectively). Each dose was consumed for 4 d, and daily iodine intake, excretion and retention were assessed. All participants were in negative iodine balance throughout the study. Iodine intake, excretion and retention differed among the three iodine levels (P < 0·01 for all groups). The zero-iodine balance derived from a random effect model indicated a mean iodine intake of 102 μg/d, but poor correlation coefficients between observed and predicted iodine excretion (r 0·538 for μg/d data) and retention (r 0·304 for μg/d data). As iodine intake increased from medium to high, all of the increased iodine was excreted (‘overflow’) through urine and faeces by males, and 89·5 % was excreted by females. Although the high iodine level (63·4 μg/d) might be adequate in males, the corresponding level of 61·6 μg/d in females did not meet optimal requirements. Our findings indicate that a daily iodine intake of approximately half the current recommended nutrient intake (120 μg/d) may satisfy the minimum iodine requirements of young male adults in China, while a similar level is insufficient for females based on the ‘iodine overflow’ hypothesis.
Outbreaks of norovirus-associated gastroenteritis have been reported in schools in recent decades in China. For early warning and response to infectious disease outbreaks, the Shanghai Infectious Diseases Bud Event Surveillance System (IDBESS) was established in 2016. Bud event is a term used for the early sign of a potential infectious disease outbreak in public settings when the first few cases appear. This study aimed to describe the epidemiological characteristics of Norovirus-associated gastroenteritis bud events from June 2016 to December 2017 and to understand factors influencing the severity of events. Data were extracted from the IDBESS, supplemented by field investigations and school absence surveillance. In total, 189 bud events of Norovirus-associated gastroenteritis were reported in schools and kindergartens, affecting 3827 individuals and 52.38% happened in primary schools. The attack rate of Norovirus-associated gastroenteritis was 3.82% on average in students in the affected schools. In each event, case numbers varied between 5 and 148, with a median of 16. The duration of bud events lasted for 2 days on average. School absence happened in 47.93% (1797/3749) of affected students and the average duration of absence was 3.07 days. It was found that a longer delay before reporting was associated with a longer-lasting duration of bud event (OR = 2.25, 95% CI: 1.65, 3.07). In conclusion, ascribed to the sensitive threshold for alerting and the timely field investigation, the surveillance of bud events of Norovirus-associated gastroenteritis is effective in the control of Norovirus infection among preschool children and students in Shanghai.
We investigate the phased evolution and variation of the South Asian monsoon and resulting weathering intensity and physical erosion in the Himalaya–Karakoram Mountains since late Pliocene time (c. 3.4 Ma) using a comprehensive approach. Neodymium and strontium isotopic compositions and single-grain zircon U–Pb age spectra reveal the sources of the deposits in the east Arabian Sea, and show a combination of sources from the Himalaya and the Karakoram–Kohistan–Ladakh Mountains, with sediments from the Indian Peninsula such as the Deccan Traps or Craton. We interpret shifts in the sediment sources to have been forced by sea-level changes that correlate with South Asian monsoon rainfall variation since late Pliocene time. We collected 908 samples from the International Ocean Discovery Program Hole U1456A, which was drilled in the east Arabian Sea. Time series of hematite content and grain size of the sediments were examined downcore. We found South Asian monsoon precipitation and weathering intensity experienced three phases from late Pliocene time. Lower monsoon precipitation, with a lower variability and strong weathering intensity, occurred during 3.4–2.4 Ma; an increased and more variable South Asian monsoon rainfall, along with strengthened but fluctuating weathering intensity, occurred at 1.8–1.1 Ma; and a reduced rainfall with lower South Asian monsoon precipitation variability and moderate weathering intensity marked the period 1.1–0.1 Ma. Maximum entropy spectral analysis and wavelet transform show that there were orbital-dominated cycles of periods c. 100 and c. 41 ka in these proxy-based time series. We propose that the monsoon, sea level, global temperature and insolation together forced the weathering and erosion in SW Asia.
In recent years, men who have sex with men (MSM) constitute a major group of HIV transmission in China. High primary drug-resistance (PDR) rate in MSM also represents a serious challenge for the Chinese antiretroviral therapy (ART) program. To assess the efficiency of ART in controlling HIV/AIDS infection among MSM, we developed a compartmental model for the annually reported HIV/AIDS MSM from 2007 to 2019 in the Zhejiang Province of China. R0 was 2.3946 (95% CI (2.2961–2.4881)). We predict that 90% of diagnosed HIV/AIDS individuals will have received treatment till 2020, while the proportion of the diagnosed remains as low as 40%. Even when the proportion of the diagnosed reaches 90%, R0 is still larger than the level of AIDS epidemic elimination. ART can effectively control the spread of HIV, even in the presence of drug resistance. The 90-90-90 strategy alone may not eliminate the HIV epidemic in Chinese MSM. Behavioural and biologic interventions are the most effective interventions to control the HIV/AIDS epidemic among MSM.
In this research paper we filter and verify miRNAs which may target silent information regulator homolog 2 (SIRT2) gene and then describe the mechanism whereby miRNA-212 might regulate lipogenic genes in mammary epithelial cell lines via targeting SIRT2. Bioinformatics analysis revealed that the bovine SIRT2 gene is regulated by three miRNAs: miR-212, miR-375 and miR-655. The three miRNAs were verified and screened by qRT-PCR, western blot, and luciferase multiplex verification techniques and only miR-212 was shown to have a targeting relationship with SIRT2. The results of co-transfecting miR-212 and silencing RNA (siRNA) showed that by targeting SIRT2, miR-212 can regulate the expression of fatty acid synthetase (FASN) and sterol regulatory element binding factor 1 (SREBP1) but not peroxisome proliferator-activated receptor gamma (PPARγ). Measurement of triglyceride (TAG) content showed that miR-212 increased the fat content of mammary epithelial cell lines. The study indicates that miR-212 could target and inhibit the expression of the SIRT2 gene to promote lipogenesis in mammary epithelial cell lines.
Hand, foot and mouth disease (HFMD) has high prevalence around the world, with serious consequences for children. Due to the long survival period of HFMD virus in ambient air, air pollutants may play a critical role in HFMD epidemics. We collected data on daily cases of HFMD among children aged 0–14 years in Ningbo City between 2014 and 2016. Distributed lag nonlinear models were used to assess the effects of particulate matter (PM2.5), sulphur dioxide (SO2), nitrogen dioxide (NO2) and ozone (O3) on the daily incidence of HFMD among children, with analyses stratified by gender and age. Compared with moderate levels of air pollution, high SO2 levels had a relative risk (RR) of 2.32 (95% CI 1.42–3.79) and high NO2 levels had a RR of 2.01 (95% CI 1.22–3.31). The RR of O3 was 2.12 (95% CI 1.47–3.05) and that of PM2.5 was 0.77 (95% CI 0.64–0.92) at moderate levels of air pollution. Specifically, high levels of SO2 and NO2 had RRs of 2.39 (95% CI 1.44–3.96) and 2.02 (95% CI 1.21–3.39), respectively, among 0–4-year-old children, while high O3 had an RR of 2.31 (95% CI 1.09–4.89) among 5–14-year-old children. Our findings suggest significant associations of high SO2 and NO2 levels and moderate O3 levels in HFMD epidemics, and also indicate that air pollution causes lagged effects on HFMD epidemics. Our study provides practical and useful data for targeted prevention and control of HMFD based on environmental evidence.
Clay often has severe detrimental impacts on cement-based materials. Therefore, it is necessary to investigate the mechanism causing the deterioration to improve the service life of cement-based materials. Based on accurate dimensional analysis, a mechanism that influences clay is proposed: the intercalation of the side chains of superplasticizer molecules in the interlayer space of the clay. To lessen this harmful effect, a new clay-resistant admixture (CRA) possessing cationic groups of small molecular size was synthesized through a novel dimensional design. The length and width of the side chains of this superplasticizer molecule were 9.50–17.50 and 0.25–0.40 nm, respectively, with a radius of ~3.74 nm in solvent, which is larger than the interlayer spacing of montmorillonite (i.e. 1.09–2.14 nm). The longitudinal and latitudinal lengths of the CRA molecule were 0.468 and 9.456 nm, respectively, ensuring intercalation in the interlayer of montmorillonite. The increase in interlayer spacing of the clay was 0.364 nm following addition of polycarboxylate superplasticizer (PCE) plus CRA and 0.632 nm following addition of PCE, which suggests that the CRA plays the role of a ‘sacrificial agent’ that is preferentially intercalated into the interlayer space of clay to further prevent the side chains of the superplasticizer molecules from entering the interlayer. The aim of this study was to propose a suitable means of synthesizing a new CRA to address the impact of clay through dimensional design and mechanism analysis, which contributes to the theoretical study and technological improvement of cement-based materials.
The health and social benefits of volunteering behaviours by older adults are well acknowledged. However, few review articles have been concerned with the correlates/dimensions of older adults’ volunteerism. Some focused only on the North American context or reviewed studies only up to 2008. This study reviewed the recent global literature in the past decade about the correlates of older adults’ volunteerism. We carried out a literature search in PsycINFO, Social Services Abstracts, Sociological Abstracts and Google Scholar to identify empirical journal publications about the correlates of older adults’ (age 60+) volunteerism from 2008 to 2019. Among 112 initially eligible papers, 41 were selected. Findings were synthesised using the framework of the Socioecological Model. Existing studies mainly have used quantitative methodologies and were conducted within the context of a single Western country. Motivations included higher education, morale and mentality, previous experiences, social network, community cohesion and organisational management. Major barriers were health and financial constraints. Few studies focused on macro-level correlates. Irrelevant and confounding correlates were also discussed. We suggest practitioners recruit and retain older volunteers by identifying their needs and optimising management within the organisation. Policy makers should create a supportive environment and increase resource accessibility. Future research could conduct cross-cultural comparisons, use diverse methodologies and embrace more correlates, especially at the macro-level.
Recently, layered double hydroxides (LDHs) have attracted intensive research interest as the next-generation supercapacitor electrodes due to their unique two-dimensional (2D) hydrotalcite-like structure. However, the inevitable agglomeration significantly decreases the accessible surface areas and blocks the pseudocapacitive sites, thus severely hinders their electrochemical applications. Herein, we develop a facile one-step growth approach to fabricate porous agglomerate of NiCo-LDH nanosheets and reduced graphene oxide (rGO) nanoflakes. By adjusting feeding molar ratios, the obtained NiCo-LDH/rGO electrode delivers a high specific capacity of 879.5 C/g at a current density of 0.5 A/g and still remains 485 C/g at 20 A/g. Furthermore, the fabricated asymmetric supercapacitor (ASC) has demonstrated a superior energy density of 48.7 W h/kg at a power density of 401 W/kg. After 2000 cycles, the assembled ASC exhibits an improved capacity retention of 81% within a potential window of 1.6 V at 2 A/g.
A simple composition of TeO2–Yb2O3 binary glass was selected as the host glass matrix for discussing the structure of tellurite glass with increasing Yb2O3 content. Raman spectra were measured to investigate the structure of the binary tellurite glasses, and upconversion and downconversion fluorescence characteristics were employed for discussing the relationship between the structural units and the state of Yb3+ in the tellurite glasses. The results suggested that the decrease of TeO4/2 in the glasses would result in the formation of Yb3+ clusters and Yb3+–O2− couple in the tellurite glasses, and then results in the decrease of cooperative upconversion and downconversion fluorescence intensity.
Losing one's only child is a major traumatic life event that may lead to post-traumatic stress disorder (PTSD); however, the underlying mechanisms of its psychological consequences remain poorly understood. Here, we investigated subregional hippocampal functional connectivity (FC) networks based on resting-state functional magnetic resonance imaging and the deoxyribonucleic acid methylation of the human glucocorticoid receptor gene (NR3C1) in adults who had lost their only child.
Methods
A total of 144 Han Chinese adults who had lost their only child (51 adults with PTSD and 93 non-PTSD adults [trauma-exposed controls]) and 50 controls without trauma exposure were included in this fMRI study (age: 40–67 years). FCs between hippocampal subdivisions (four regions in each hemisphere: cornu ammonis1 [CA1], CA2, CA3, and dentate gyrus [DG]) and methylation levels of the NR3C1 gene were compared among the three groups.
Results
Trauma-exposed adults, regardless of PTSD diagnosis, had weaker positive FC between the left hippocampal CA1, left DG, and the posterior cingulate cortex, and weaker negative FC between the right CA1, right DG, and several frontal gyri, relative to healthy controls. Compared to non-PTSD adults, PTSD adults showed decreased negative FC between the right CA1 region and the right middle/inferior frontal gyri (MFG/IFG), and decreased negative FC between the right DG and the right superior frontal gyrus and left MFG. Both trauma-exposed groups showed lower methylation levels of the NR3C1 gene.
Conclusions
Adults who had lost their only child may experience disrupted hippocampal network connectivity and NR3C1 methylation status, regardless of whether they have developed PTSD.