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Encrinurids are common in Ordovician and Silurian strata but whether they survived into the Early Devonian is still controversial. This paper documents the encrinurid Batocara sp. near the Silurian–Devonian boundary in western Junggar, Xinjiang. The highest horizon of Batocara sp. is located above the first appearance datum of the Devonian conodont Caudicriodus, confirming that encrinurids may cross the Silurian–Devonian boundary. The presence of Caudicriodus angustoides bidentatus, Zieglerodina planilingu and plate-type loboliths of scyphocrinoids above the highest horizon of Batocara sp. indicates that encrinurids here extend only into the lower part of the first conodont zone of the Lochkovian (i.e., Caudicriodus hesperius Biozone). Encrinurids are widely distributed and easily recognized, and unlike graptolites and conodonts are not controlled by lithofacies. Therefore, it might be possible to use the highest horizon of encrinurids as indicator fossils to identify the approximate position of the Silurian–Devonian boundary in areas or sections where graptolites and conodonts are not present, and at least in northwest China.
We describe an outbreak of echovirus 18 infection involving 10 patients in our neonatal intensive care unit (an attack rate of 33%). The mean age at the onset of illness was 26.8 days. Eighty percent were preterm infants. All were discharged home without sequelae. There were no differences in gestation age, birth weight, delivery mode, use of antibiotics, and parenteral nutrition between the enterovirus (EV) group and non-EV group, but the rate of breastfeeding was significantly higher in the EV group. Separation care and reinforcement of hand-washing seemed to be effective in preventing further spread of the virus. Visiting policy, hygiene practice, and handling of expressed breastmilk should be reinforced.
Previous studies on older adults' intention to adopt medical apps during irregular circumstances like the COVID-19 outbreak are still in its infancy. In order to fill this knowledge gap, we developed a theoretical framework based on the Unified Theory of Acceptance and Use of Technology (UTAUT) model and the Technology of Acceptance Model (TAM) to explain Chinese older people's willingness to use medical apps during the COVID-19 pandemic. We collected 1,318 online questionnaires during the first wave of the pandemic in China in early 2020. We employed structural equation modelling to analyse the data, and the results show that (a) attitudes towards using apps influence older people's intention to use apps significantly; (b) only two factors, perceived usefulness and facilitating conditions, which were proposed in the UTAUT model, significantly predicted the older adults' intention to use apps, but not others; and (c) perceived usefulness, perceived ease of use, subjective norm and facilitating conditions all significantly impact attitudes towards using apps. Further mediation analysis found that attitudes towards using apps significantly mediated the paths suggested in the original UTAUT model. Due to the online survey method we used, older people who do not use the internet were excluded from our sampling process. However, our timely research contributes to the existing literature by showcasing older people's usage of eHealth technology in public health emergencies. It also builds on the broader discussions on technology use by combining the TAM and the UTAUT model, highlighting the vital role of people's attitude towards using technology in shaping their intention to use it.
Pharmacological treatment of major depressive disorder is often inefficient, and multiple strategies are used for inadequate response to antidepressants. Second-generation antipsychotics are used as augmentation measures in clinical practice; evidence of their efficacy and acceptability is insufficient, and it remains confusing as to which drug should be selected first. In this systematic review and network meta-analysis, we included randomised controlled trials of second-generation antipsychotics used as adjunctive treatment in patients with suboptimal responses. Outcome measures were efficacy (response and remission) and acceptability (dropout due to any reason and adverse events). Thirty-three trials comprising 10 602 participants were included. Regarding efficacy, response rates indicated that all antipsychotics except for ziprasidone were more efficacious than the placebo, with the odds ratios (ORs) ranging from 1.34 for olanzapine and cariprazine [95% credible interval (CrI) 1.04–1.73 and 1.07–1.67, respectively] to 2.17 for risperidone (95% CrI 1.38–3.42). When considering remission, cariprazine was not effective (OR 1.21, 95% CrI 0.96–1.54). For acceptability, quetiapine (OR 0.68, 95% CrI 0.50–0.91), brexpiprazole (OR 0.69, 95% CrI 0.55–0.86), and cariprazine (OR 0.61, 95% CrI 0.46–0.82) were worse than the placebo. With regards to tolerability, only olanzapine (OR 0.51, 95% CrI 0.25–1.07) and risperidone (OR 0.48, 95% CrI 0.10–2.21) showed no significant differences compared with placebo. The administration of adjunctive antipsychotics is associated with high effectiveness and low acceptability. Risperidone and aripiprazole are more efficacious and accepted than other atypical antipsychotics.
This article investigates the recent proliferation of family-themed homosexual stories in China based on life-history interviews and participant observation conducted in Shenzhen. We develop the concept of “neo-Confucian homonormativity” – characterized by a harmonious relationship between gay men and their families of origin and their ability and aspiration to enter a monogamous relationship and become parents – to explain the production, circulation and consumption of these stories in the Chinese gay community. We argue that these stories are socially embedded actions enabled by the emerging neoliberal sexual politics in the Chinese gay community that influence the organization of the Chinese gay community and Chinese gay men's lived experiences. By analysing the emerging storytelling practices in the Chinese gay community, this article challenges the Western-centric way of theorizing homonormativity and opens up the possibility to conceptualize homonormativity from an Asian perspective.
Lower Cretaceous sedimentary rocks of Lingshan Island, located along the continental margin of East Asia, have received increased attention. The Lingke-1 core mainly belongs to the Lower Cretaceous Laiyang Group. We investigate provenance, tectonic setting, palaeoclimate and palaeoredox conditions in the study area using elemental geochemistry, thereby elucidating the depositional history of the Lower Cretaceous sediments and reconstructing the palaeo-environment. To achieve this, 90 siltstones and 76 mudstones were sampled from this core and other outcrops on Lingshan Island. The chemical index of alternation (CIA) values for the majority of the samples and the bivariate diagrams indicate that the sedimentary rocks were subjected to minor weathering processes. Geochemical results suggest that source rocks for the region are felsic igneous and metamorphic rocks, along with minor proportions of intermediate igneous rocks. Major- and trace-element discrimination diagrams, deciphering the tectonic history, indicate that source rocks mainly originated from the continental island-arc and active continental margin. Several representative geochemical indices and the bivariate plots based on elemental contents show that the Laiyang Group was predominantly deposited in arid conditions. Sr/Ba values suggest a palaeosalinity transition from brackish to saline, demonstrating a depositional transformation from lacustrine facies for the lower Laiyang Group to marine facies in the upper Laiyang Group. U/Th and V/(V+Ni) ratios and Ce anomalies in the rocks indicate anoxic conditions. We conclude that the conspicuous decline in the trends of the above three geochemical indices, ranging between 400 and 800 m, may be related to the latest Hauterivian oceanic anoxic event.
The breakup process of a charged, leaky-dielectric jet subjected to an axial perturbation is computationally analysed from the perspectives of linear and nonlinear dynamics using the arbitrary Lagrangian–Eulerian technique. The linear dynamics of the leaky-dielectric jet is quantitatively predicted by the dispersion relation from the linear stability analysis. Regarding the nonlinear dynamics, it is found that the charge relaxation is responsible for the radial compression of satellite droplets, which is validated by experiments. Two types of charge relaxations, namely, ohmic conduction and surface charge convection, define the pinching process into three breakup modes, i.e. ligament pinching, end pinching and transition pinching. In the ligament-pinching mode, the ohmic conduction dominates the jet breakup since the charge relaxes to the jet ligament instantaneously. In contrast, the surface charge convection takes effect in the end-pinching mode since the surface charge is convected to the jet end via fluid flow. When the ohmic conduction is comparable to the surface charge convection, the breakup occurs simultaneously at the end and the ligament. Finally, the influences of the perturbed wavenumber, the electric field intensity and the viscosity on the breakup mode and the local dynamics at pinch-off are comprehensively discussed.
This study proposed a novel ensemble analysis strategy to improve hand, foot and mouth disease (HFMD) prediction by integrating environmental data. The approach began by establishing a vector autoregressive model (VAR). Then, a dynamic Bayesian networks (DBN) model was used for variable selection of environmental factors. Finally, a VAR model with constraints (CVAR) was established for predicting the incidence of HFMD in Chengdu city from 2011 to 2017. DBN showed that temperature was related to HFMD at lags 1 and 2. Humidity, wind speed, sunshine, PM10, SO2 and NO2 were related to HFMD at lag 2. Compared with the autoregressive integrated moving average model with external variables (ARIMAX), the CVAR model had a higher coefficient of determination (R2, average difference: + 2.11%; t = 6.2051, P = 0.0003 < 0.05), a lower root mean-squared error (−24.88%; t = −5.2898, P = 0.0007 < 0.05) and a lower mean absolute percentage error (−16.69%; t = −4.3647, P = 0.0024 < 0.05). The accuracy of predicting the time-series shape was 88.16% for the CVAR model and 86.41% for ARIMAX. The CVAR model performed better in terms of variable selection, model interpretation and prediction. Therefore, it could be used by health authorities to identify potential HFMD outbreaks and develop disease control measures.
Hydrocarbon contamination plagues high-resolution and analytical electron microscopy by depositing carbonaceous layers onto surfaces during electron irradiation, which can render carefully prepared specimens useless. Increased specimen thickness degrades resolution with beam broadening alongside loss of contrast. The large inelastic cross-section of carbon hampers accurate atomic species detection. Oxygen and water molecules pose problems of lattice damage by chemically etching the specimen during imaging. These constraints on high-resolution and spectroscopic imaging demand clean, high-vacuum microscopes with dry pumps. Here, we present an open-hardware design of a high-vacuum manifold for transmission electron microscopy (TEM) holders to mitigate hydrocarbon and residual species exposure. We quantitatively show that TEM holders are inherently dirty and introduce a range of unwanted chemical species. Overnight storage in our manifold reduces contaminants by one to two orders of magnitude and promotes two to four times faster vacuum recovery. A built-in bakeout system further reduces contaminants partial pressure to below 10−10 hPa (Torr) (approximately four orders of magnitude down from ambient storage) and alleviates monolayer adsorption during a typical TEM experiment. We determine that bakeout of TEM holder with specimen held therein is the optimal cleaning method. Our high-vacuum manifold design is published with open-source blueprints, parts, and cost list.
Previous studies have shown conflicting findings regarding the relationship between maternal vitamin D deficiency (VDD) and fetal growth restriction (FGR). We hypothesised that parathyroid hormone (PTH) may be an underlying factor relevant to this potential association. In a prospective birth cohort study, descriptive statistics were evaluated for the demographic characteristics of 3407 pregnancies in the second trimester from three antenatal clinics in Hefei, China. The association of the combined status of vitamin D and PTH with birth weight and the risk of small for gestational age (SGA) was assessed by a multivariate linear and binary logistic regression. We found that declined status of 25-hydroxyvitamin D is associated with lower birth weight (for moderate VDD: adjusted β = −49·4 g, 95 % CI −91·1, −7·8, P < 0·05; for severe VDD: adjusted β = −79·8 g, 95 % CI −127·2, −32·5, P < 0·01), as well as ascended levels of PTH (for elevated PTH: adjusted β = −44·5 g, 95 % CI −82·6, −6·4, P < 0·05). Compared with the non-VDD group with non-elevated PTH, pregnancies with severe VDD and elevated PTH had the lowest neonatal birth weight (adjusted β = −124·7 g, 95 % CI −194·6, −54·8, P < 0·001) and the highest risk of SGA (adjusted risk ratio (RR) = 3·36, 95 % CI 1·41, 8·03, P < 0·01). Notably, the highest risk of less Ca supplementation was founded in severe VDD group with elevated PTH (adjusted RR = 4·67, 95 % CI 2·78, 7·85, P < 0·001). In conclusion, elevated PTH induced by less Ca supplementation would further aggravate the risk of FGR in pregnancies with severe VDD through impaired maternal Ca metabolism homoeostasis.
Prior data on long-term association between legume consumption and hypertension risk are sparse. We aimed to evaluate whether total legume and subtype intakes prospectively associate with hypertension incidence among 8758 participants (≥30 years) from the China Health and Nutrition Survey 2004–2011. Diet was assessed by interviews combining 3-d 24-h food recalls and household food inventory weighing at each survey round. Incident hypertension was identified by self-reports or blood pressure measurements. We applied multivariable Cox regressions to estimate hazard ratios (HR) with corresponding 95 % CI for hypertension across increasing categories of cumulatively averaged legume intakes. For 35 990 person-years (median 6·0 years apiece), we documented 944 hypertension cases. After covariate adjustment, higher total legume intakes were significantly associated with lower hypertension risks, with HR comparing extreme categories being 0·56 (95 % CI 0·43, 0·71; Ptrend < 0·001). Then we found that intakes of dried legumes (HR 0·53 (95 % CI 0·43, 0·65); Ptrend < 0·001) and fresh legumes (HR 0·67 (95 % CI 0·55, 0·81); Ptrend < 0·001) were both related to decreased hypertension hazards. However, further dried legume classification revealed that negative association with hypertension substantially held for soyabean (HR 0·51 (95 % CI 0·41, 0·62); Ptrend < 0·001) but not non-soyabean intakes. In stratified analyses, the association of interest remained similar within strata by sex, BMI, physical activity, smoking and drinking status; rather, significant heterogeneity showed across age strata (Pinteraction = 0·02). Total legume consumption among the over-65s was related to a more markedly reduced hypertension risk (HR 0·47 (95 % CI 0·30, 0·73); Ptrend < 0·001). Our findings suggest an inverse association of all kinds of legume (except non-soyabean) intakes with hypertension risks.
Water-based polyurethane/alumina hollow microsphere (WPU-hAl2O3) composite films were prepared via a facile spin coating method. The pristine WPU, as the matrix of the composite films, was tailor-made by hAl2O3 with the diameter of 2–5 μm to improve the mechanical and physical properties of the films. The hardness, surface morphology, infrared emissivity, wettability, and light transmittance of the WPU-hAl2O3 films with different hAl2O3 contents were investigated. The results indicate that the Vickers hardness, coefficient of friction, infrared emissivity at the wavelength of 2–22 μm, and wetting angle of the WPU-hAl2O3 films (30 wt%) increased by 53.6%, 51.7%, 21.1%, and 19.0%, respectively, compared with the pristine WPU films. Meanwhile, with the rising of hAl2O3 content, the light transmittance decreased by 75.3% at the wavelength of 400–800 nm. This work not only designs a kind of lightweight multifunctional composite film but also provides an effective route for extending further applications of hAl2O3 in the field of composite films.
To satisfy the needs of precise pin-point landing missions in deep space exploration, this paper proposes a method based on feature line extraction and matching to estimate the attitude and position of a lander during the descent phase. Linear equations for a lander's motion parameters are given by using at least three feature lines on the planetary surface and their two-dimensional projections. Then, by taking advantage of Singular Value Decomposition (SVD), candidate solutions are obtained. Lastly, the unique lander's attitude and position relative to the landing site are selected from the candidate solutions. Simulation results show that the proposed algorithm is able to estimate a lander's attitude and position robustly and quickly. Without an extended Kalman filter, the average errors of attitude are less than 1° and the average errors of position are less than 10 m at an altitude of 2,000 m. With an extended Kalman filter, attitude errors are within 0·5° and position errors are within 1 m at an altitude of 247·9 m.
In this paper, we introduce a lower extremity exoskeleton CUHK-EXO that is developed to help paraplegic patients, who have lost the motor and sensory functions of their lower limbs to perform basic daily life motions. Since the sit-to-stand and stand-to-sit (STS) motion is the first step for paraplegic patients toward walking, analysis of the exoskeleton's applicability to the STS motion assistance is performed. First, the human-exoskeleton system (HES) is modeled as a five-link model during the STS motion, and the center of pressure (COP) on the ground and center of gravity of the whole system are calculated. Then, a description of the CUHK-EXO hardware design is presented, including the mechatronics design and actuator selection. The COP position is an important factor indicating system balance and wearer's comfort. Based on the COP position, a trajectory online modification algorithm (TOMA) is proposed for CUHK-EXO to counteract disturbances, stabilize system balance, and improve the wearer's comfort in the STS motion. The results of STS motion tests conducted with a paraplegic patient demonstrate that CUHK-EXO can provide a normal reference pattern and proper assistive torque to support the patient's STS motion. In addition, a pilot study is conducted with a healthy subject to verify the effectiveness of the proposed TOMA under external disturbances before future clinical trials. The testing results verify that CUHK-EXO can counteract disturbances, and help the wearer perform the STS motion safely and comfortably.
In recent years, hand, foot, and mouth disease (HFMD) has been increasingly recognized as a critical challenge to disease control and prevention in China. Previous studies have found that meteorological factors such as mean temperature and relative humidity were associated with HFMD. However, little is known about whether the diurnal temperature range (DTR) has any impact on HFMD. This study aimed to quantify the impact of DTR on childhood HFMD in 18 cities in Sichuan Province. A distributed lag non-linear model was adopted to explore the temporal lagged association of daily temperature with age-, gender- and pathogen-specific HFMD. A total of 290 123 HFMD cases aged 0–14 years were reported in the 18 cities in Sichuan Province. The DTR–HFMD relationships were non-linear in all subgroups. Children aged 6–14 years and male children were more vulnerable to the temperature changes. Large DTR had the higher risk estimates of HFMD incidence in cases of EV71 infection, while small DTR had the higher risk estimates of HFMD incidence in cases of CV-A16 infection. Our study suggested that DTR played an important role in the transmission of HFMD with non-linear and delayed effects.
Structural distortions at the nanoscale are delicately linked with many exotic properties for ferroic thin films. Based on advanced aberration corrected scanning transmission electron microscopy, we observe BiFeO3 thin films with variant tensile strain states and demonstrate at an atomic scale the interplay of intrinsic spontaneous structural distortions with external constraints. Structural parameters (the rhombohedral distortion and domain wall shear distortion) under zero (BiFeO3/GdScO3) and 1.5% (BiFeO3/PrScO3) lateral strain states are quantitatively analyzed which are suppressed within a few unit cells near the film/substrate interfaces. In particular, an interfacial layer with asymmetrical lattice distortions (enhanced and reduced out-of-plane lattice spacing) on the two sides of 109° domain wall is resolved. These structural distortions near the film/substrate interface in ferroic thin films reveal intense tanglement of intrinsic distortions of BiFeO3 with external boundary conditions, which could provide new insights for the development of nanoscale ferroelectric devices.
By reflowing Cu/Sn/Ni ultrafine interconnects under a temperature gradient, a new transient liquid phase (TLP) bonding process was proposed for three-dimensional packaging applications. The evolution of the dominant (Cu,Ni)6Sn5 intermetallic compounds depends strongly on the temperature gradient. The essential cause of such dependence is attributed to the different amounts of Cu and Ni atomic fluxes being introduced into the liquid solder. Under the coupling effect of thermomigration and Cu–Ni cross-interaction, the total atomic flux of Cu and Ni is promoted. As a result, the growth of dense (Cu,Ni)6Sn5 is significantly accelerated and the formation of Cu3Sn is eliminated. The new TLP bonding process consumes only a limited amount of the Ni substrate, but much more from the Cu substrate. The mechanism for the new TLP bonding process is discussed and experimentally verified in this study.
Numerous studies have been conducted on the cellular morphology of Cryptocaryon irritans. However, details regarding the tomont stage of its life cycle remain lacking. In this study, we investigated the morphology of the tomont stage throughout encystment and cell division using light and electron microscopy. Results showed that there was no secretion of encystation-specific secretory vesicles or extrusomes during formation of the cyst wall. Instead, the synthesis and construction of the C. irritans cyst wall materials may involve molecular events at the pellicle. The somatic cilia and the cytostome were present during encystment and covered by the newly formed cyst wall. New somatic cilia were continuously created between old cilia and showed various lengths during cell division, a process that was similar to morphogenesis in many free-living ciliates. During cell division inside the tomont, dividing daughter cells formed temporary cell chains with no oral primordia before separating from each other into dissociative tomite precursors. The process of cell division may not be accompanied by stomatogenesis, and new oral primordia in offspring cells likely formed before the dividing cell chains split into dissociative spherical tomites. Mitochondrial autophagy was observed in encysting C. irritans cells. Numerous endosymbionts and Golgi structures were observed in the tomont cytoplasm. Cellular metabolic activity in the C. irritans tomont was quite high, with large amounts of materials or cellular organelles potentially being synthesized and prepared for the following infective theront stage.