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Thrombocytopenia occasionally occurs following the closure of some giant patent ductus arteriosus cases. Unfortunately, there is no associated research describing the associated risk factors for thrombocytopenia post-procedure.
We reviewed all patients who received occluders with sizes ≥10/12 mm between January 2013 and June 2019. All the data and information on the characteristics of the patients and their follow-up were recorded. Univariate analysis, receiver operating characteristic curves, and linear regression were used to analyse the risk factors for thrombocytopenia and the predictors of hospitalisation stay.
Finally, 32 patients (17.5%) suffered from thrombocytopenia. Univariate analysis revealed the ratio between occluder disc size (mm) and body weight (kg) (1.71 ± 0.51 versus 1.35 ± 0.53) as an independent predictive factor for thrombocytopenia, and the area under the curve of the ratio of occluder size and body weight for predicting thrombocytopenia post-closure was 0.691 (95% confidence interval: 0.589–0.792, p = 0.001). The best cut-off value for the ratio of occluder size and weight was 1.5895, with a sensitivity and specificity of 68.8 and 66.9%, respectively. Each unit of the ratio of occluder size and body weight predicted an average hospitalisation stay of 2.856 days (95% confidence interval: 1.380–4.332). Treatment with medication did not reduce the hospitalisation stay or benefit platelet restoration.
Once the ratio of occluder size and body weight is greater than 1.6, thrombocytopenia always exists. Every unit of the ratio of occluder size and body weight represents an additional 3 days of hospitalisation. Treatment does not reduce the duration of hospitalisation.
Neuroimaging characteristics have demonstrated disrupted functional organization in schizophrenia (SZ), involving large-scale networks within grey matter (GM). However, previous studies have ignored the role of white matter (WM) in supporting brain function.
Using resting-state functional MRI and graph theoretical approaches, we investigated global topological disruptions of large-scale WM and GM networks in 93 SZ patients and 122 controls. Six global properties [clustering coefficient (Cp), shortest path length (Lp), local efficiency (Eloc), small-worldness (σ), hierarchy (β) and synchronization (S) and three nodal metrics [nodal degree (Knodal), nodal efficiency (Enodal) and nodal betweenness (Bnodal)] were utilized to quantify the topological organization in both WM and GM networks.
At the network level, both WM and GM networks exhibited reductions in Eloc, Cp and S in SZ. The SZ group showed reduced σ and β only for the WM network. Furthermore, the Cp, Eloc and S of the WM network were negatively correlated with negative symptoms in SZ. At the nodal level, the SZ showed nodal disturbances in the corpus callosum, optic radiation, posterior corona radiata and tempo-occipital WM tracts. For GM, the SZ manifested increased nodal centralities in frontoparietal regions and decreased nodal centralities in temporal regions.
These findings provide the first evidence for abnormal global topological properties in SZ from the perspective of a substantial whole brain, including GM and WM. Nodal centralities enhance GM areas, along with a reduction in adjacent WM, suggest that WM functional alterations may be compensated for adjacent GM impairments in SZ.
To investigate homocysteine (Hcy) and folate levels, prevalence of hyperhomocysteinaemia (HHcy) and folate deficiency, which are affected by lifestyles in urban, agricultural and stock-raising populations.
This is a cross-sectional study.
Urban, agricultural and stock-raising regions in Emin, China.
Totally 1926 subjects – 885 (45·9 %) from urban, 861 (44·7 %) from agricultural and 180 (9·4 %) from stock-raising regions – were obtained using multistage stratified random sampling. Inclusion criteria encompassed inhabitants aged ≥15 years who resided at the current address for ≥6 months and agreed to participate in the study. Surveys on health behaviour questionnaires and physical examinations were conducted and blood samples collected.
The folate level of subjects from the stock-raising region was the lowest, followed by those from the agricultural region, and the highest in those from the urban region (3·48 v. 6·50 v. 7·12 ng/ml, P < 0·001), whereas mean Hcy showed no significant difference across regions. The OR for HHcy in stock-raising regions was 1·90 (95 % CI 1·11, 3·27) compared with the urban region after adjusting for all possible covariates. The OR for folate deficiency in stock-raising and agriculture regions was 11·51 (95 % CI 7·09, 18·67) and 1·91 (95 % CI 1·30, 2·82), respectively, compared with the urban region after adjusting for all possible covariates.
HHcy and folate deficiency are highly prevalent in stock-raisers, which is of important reference for HHcy control in Xinjiang, with a possibility of extension to others with approximate lifestyles.
Since December 2019, several new infectious diseases, mainly lung diseases caused by novel coronavirus infections, have been discovered in Wuhan, Hubei Province. With the spread of the epidemic, cases in other regions of China and abroad have been confirmed. This sudden outbreak of a new type of infectious disease has seriously threatened people’s health and safety, and China has adopted strong prevention and control measures in response. To provide a reference for international health emergency management workers, this article summarizes, from an academic perspective, the main prevention and control measures taken in China.
Cinnamomum chago is a woody species of the family Lauraceae endemic to Yunnan province, China, previously known from only one location, and categorized as a Plant Species with Extremely Small Population. We surveyed to determine the distribution and population size of C. chago, characterize its habitat, identify any threats, assess its conservation status, and provide guidelines for its management and conservation. During 2014–2017 we found only 64 mature C. chago, in five locations. These small, fragmented populations occur along Lancang River in Dali Prefecture at altitudes of 2,200–2,400 m. The species' extent of occurrence is c. 923 km2, with an area of occupancy of c. 60 km2. The habitat of the species has been degraded by expansion of pastoral activities and deforestation. We recommend categorization of C. chago as Endangered on the IUCN Red List, prevention of the collection of seeds and wood of the species, protection and monitoring, and ex situ propagation for future reintroductions.
Endometrial injury is an important cause of intrauterine adhesion (IUA), amenorrhea and infertility in women, with limited effective therapies. Recently, stem cells have been used in animal experiments to repair and improve injured endometrium. To date, our understanding of adipose-derived stem cells (ADSCs) in endometrial injury repair and their further therapeutic mechanisms is incomplete. Here, we examined the benefit of ADSCs in restoration of injured endometrium by applying a rat endometrial injury model. The results revealed by immunofluorescence showed that green fluorescent protein (GFP)-labelled ADSCs can differentiate into endometrial epithelial cells in vivo. At 30 days after ADSCs transplantation, injured endometrium was significantly improved, with increased microvessel density, endometrial thickness and glands when compared with the model group. Furthermore, the fertility of rats with injured endometrium in ADSCs group was improved and had a higher conception rate (60% vs 20%, P = 0.014) compared with the control phosphate-buffered saline (PBS) group. However, there was no difference in the control group compared with the sham group. In addition, expression levels of the oestrogen receptor Eα/β (ERα, ERβ) and progesterone receptor (PR) detected by western blot and enzyme-linked immunosorbent assay (ELISA) were higher in the ADSCs group than in the PBS group. Taken together, these results suggested that ADSC transplantation could improve endometrial injury as a novel therapy for IUA.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
This study was conducted to investigate the protective effects of l-threonine (l-Thr) supplementation on growth performance, inflammatory responses and intestinal barrier function of young broilers challenged with lipopolysaccharide (LPS). A total of 144 1-d-old male chicks were allocated to one of three treatments: non-challenged broilers fed a basal diet (control group), LPS-challenged broilers fed a basal diet without l-Thr supplementation and LPS-challenged broilers fed a basal diet supplemented with 3·0 g/kg l-Thr. LPS challenge was performed intraperitoneally at 17, 19 and 21 d of age, whereas the control group received physiological saline injection. Compared with the control group, LPS challenge impaired growth performance of broilers, and l-Thr administration reversed LPS-induced increase in feed/gain ratio. LPS challenge elevated blood cell counts related to inflammation, and pro-inflammatory cytokine concentrations in serum (IL-1β and TNF-α), spleen (IL-1β and TNF-α) and intestinal mucosa (jejunal interferon-γ (IFN-γ) and ileal IL-1β). The concentrations of intestinal cytokines in LPS-challenged broilers were reduced by l-Thr supplementation. LPS administration increased circulating d-lactic acid concentration, whereas it reduced villus height, the ratio between villus height and crypt depth and goblet density in both jejunum and ileum. LPS-induced decreases in jejunal villus height, intestinal villus height:crypt depth ratio and ileal goblet cell density were reversed with l-Thr supplementation. Similarly, LPS-induced alterations in the intestinal mRNA abundances of genes related to intestinal inflammation and barrier function (jejunal toll-like receptor 4, IFN-γ and claudin-3, and ileal IL-1β and zonula occludens-1) were normalised with l-Thr administration. It can be concluded that l-Thr supplementation could attenuate LPS-induced inflammatory responses and intestinal barrier damage of young broilers.
Salt, promoting oxidative stress, contributes to insulin resistance, whereas K, inhibiting oxidative stress, improves insulin sensitivity. Oxidative stress activation of NLRP3 inflammasome is a central player in the induction of insulin resistance. Therefore, we hypothesised that NLRP3 inflammasome may mediate the effects of salt and K on insulin resistance. In all, fifty normotensive subjects were recruited from a rural community of Northern China. The protocol included a low-salt diet for 7 d, then a high-salt diet for 7 d and a high-salt diet with K supplementation for another 7 d. In addition, THP-1 cells were cultured in different levels of Na with and without K. The results showed that salt loading elevated fasting blood glucose, insulin and C-peptide levels, as well as insulin resistance, whereas K supplementation reversed them. Meanwhile, additional K reversed the active effects of high salt on NLRP3 inflammasome in both the subjects and THP-1 cells, and the change of insulin resistance index notably related with the alteration of plasma IL-1β, the index of NLRP3 inflammasome activation, during intervention in the subjects. Additional K ameliorated oxidative stress induced by high salt in both the subjects and cultured THP-1 cells, and the change of oxidative stress related with the alteration of plasma IL-1β during intervention in the subjects. In vitro, antioxidant N-acetyl-l-cysteine significantly prevented the active effects of high Na or oxidant Rosup on NLRP3 inflammasome, so did K. Our study indicates that oxidative stress modulation of NLRP3 inflammasome may be involved in the impacts of Na and K on insulin resistance.
Doctors have a higher prevalence of mental ill health compared with other professional occupations but incidence rates are poorly studied.
To determine incidence rates and trends of work-related ill health (WRIH) and work-related mental ill health (WRMIH) in doctors compared with other professions in Great Britain.
Incidence rates were calculated using an occupational physician reporting scheme from 2005–2010. Multilevel regression was use to study incidence rates from 2001 to 2014.
Annual incidence rates for WRIH and WRIMH in doctors were 515 and 431 per 100000 people employed, respectively. Higher incidence rates for WRIH and WRMIH were observed for ambulance staff and nurses, respectively. Doctors demonstrated an annual average incidence rates increase for WRIH and WRMIH, especially in women, whereas the other occupations demonstrated a decreasing or static trend. The difference in trends between the occupations was statistically significant.
WRIH and WRMIH incidence rate are increasing in doctors, especially in women, warranting further research.
With the improvement of the bias instability of Micro-Electromechanical Systems (MEMS) gyroscopes, the g-sensitivity error is gradually becoming one of the more important factors that affects the dynamic accuracy of a MEMS gyroscope. Hence there is a need for correcting the g-sensitivity error. However, the traditional calibration of g-sensitivity error uses a centrifuge. The calibration conditions are harsh, the process is complex and the cost is relatively high. In this paper, a fast and simple method of g-sensitivity error calibration for MEMS gyroscopes is proposed. With respect to the bias and random noise of a MEMS gyroscope, the g-sensitivity error magnitude is relatively small and it is simultaneously coupled with the Earth's rotation rate. Therefore, in order to correct the g-sensitivity error, this work models the calibration for g-sensitivity error coefficients, designs an (8+N)-position calibration scheme, and then proposes a fitting method for g-sensitivity error coefficients based on the Newton iteration and least squares methods. Multi-group calibration experiments designed on a MEMS Inertial Measurement Unit (MEMS IMU) product demonstrate that the proposed method can calibrate g-sensitivity error coefficients and correct the g-sensitivity error effectively and simply.
Leaders’ implicit followership theory describes leaders’ personal assumptions about the traits and behaviors that characterize followers. Unlike traditional organizational behavior research, studies on leaders’ implicit followership theory can deepen our understandings of ‘how leaders and followers perceive, decide and take action’ from follower-centric perspective. Adopting 267 follower–leader dyads from 16 Chinese enterprises as our final sample, we found that: (1) positive leaders’ implicit followership theory had significant positive effect on followers’ creativity; (2) followers’ leader–member exchange with leader, intrinsic motivation and creative self-efficacy mediated the positive relationship between positive leaders’ implicit followership theory and followers’ creativity; (3) no significance difference was found between the mediating effects of leader–member exchange, intrinsic motivation and creative self-efficacy. The current study not only extended the application of social cognitive theory in leadership research, but also made contributions to the enrichment of social exchange theory and componential theory of creativity.
A Cu–0.13Cr–0.074Ag (wt%) alloy has been synthesized by the nonvacuum melting and casting followed by thermal-mechanical treatment, and microstructure and mechanical properties have been tailored to make a trade-off between the strength and the electrical conductivity. Results illuminated that the designed alloy has a tensile strength of 473 MPa, a hardness of 140 HV, a yield strength of 446 MPa, an elongation of 10.5%, and an electrical conductivity of 94.5% IACS. Microstructure observations of the samples aged at 480 °C showed that: an fcc structure Cr-phase with a cube-on-cube orientation relationship with the Cu matrix was formed as aged for 15 min, while an ordered bcc structure Cr phase with B2 structure formed as aged for 2 h. The 3DAP results revealed that the Cr was formed to be precipitates and the Ag was formed as solutes distributing evenly in matrix. The high electrical conductivity was ascribed to the Cr element precipitated from the Cu matrix, Ag dissolved in the Cu matrix had little effect on the scattering of Cu electron.
The TiO2 hollow spheres (TiO2HS) were successfully prepared by a hydrothermal method and added to Vulcan XC-72 carbon black as the support materials for Pd nanoparticles. A facile approach to promote ethylene glycol (EG) electrooxidation in alkaline medium was carried out by the PdBi/TiO2HS-C catalyst. The results show that Pd and Bi nanoparticles are uniformly dispersed on the surface of carbon-doped TiO2 hollow spheres, the appropriate amount of Bi modification into Pd/TiO2HS-C catalyst can enhance remarkably the electrocatalytic activity for EG oxidation, in which the PdBi/TiO2HS-C (Pd:Bi = 1:0.1) catalyst exhibits excellent stability. The high electrochemical performance is attributed to the unique structure and high surface area of the TiO2HS, metal nanoparticles uniform distribution, the electronic effect between Pd and Bi as well as the bifunctional effect between metal nanoparticles and the support TiO2HS-C. The results obtained are significant for the development of new Pd-based TiO2HS-C electrocatalysts for alcohol fuel cells.
The paper aims to develop an effective preconditioner and conduct the convergence analysis of the corresponding preconditioned GMRES for the solution of discrete problems originating from multi-group radiation diffusion equations. We firstly investigate the performances of the most widely used preconditioners (ILU(k) and AMG) and their combinations (Bco and Bco), and provide drawbacks on their feasibilities. Secondly, we reveal the underlying complementarity of ILU(k) and AMG by analyzing the features suitable for AMG using more detailed measurements on multiscale nature of matrices and the effect of ILU(k) on multiscale nature. Moreover, we present an adaptive combined preconditioner Bcoα involving an improved ILU(0) along with its convergence constraints. Numerical results demonstrate that Bcoα-GMRES holds the best robustness and efficiency. At last, we analyze the convergence of GMRES with combined preconditioning which not only provides a persuasive support for our proposed algorithms, but also updates the existing estimation theory on condition numbers of combined preconditioned systems.
In this study, scanning electron microscope, electron backscatter diffraction, and transmission electron microscope have been used to investigate the microstructure evolution of Cu–0.2Mg alloy during continuous extrusion in mass production. The continuous extrusion could change the size and orientation of as-cast crystallite grains of the alloy. Hardness increased gently in upsetting zone and dropped sharply in adhesion zone. Hardness reached the maximum value in right-angle bending zone; and it decreased rapidly in extending extrusion zone. Upsetting zone was mainly composed of cell blocks and microbands, and adhesion zone mainly consisted of discontinuous recrystallize grain. Shear band and subgrains were formed in right-angle bending zone due to polygonization during shear deformation. In extending extrusion zone and extrusion rod zone, recrystallize microstructures were predominant.
Organ shortage is a severe challenge worldwide. Three-dimensional (3D) printing, a rapidly developing engineering and materials science tool, holds considerable promise in generating implantable organ scaffolds that may reduce or eliminate organ shortage. However, translation of 3D printing into clinical therapies has been astonishingly slow and certainly has not matched the pace of technology development. This review outlines challenges and opportunities for the application of 3D printing in tissue and organ regeneration, with emphasis on in vivo applications of 3D-printed scaffolds. Three-dimensional-printed scaffolds for the regeneration of complex tissues and organs, including bone, cartilage, tooth, and skin, serve as prototypes for 3D printing of other tissues and organs such as the liver, kidney, or heart. The aspiration to reduce or eliminate organ shortage appears to hinge on the translation of 3D bioprinting technologies into preclinical studies and clinical trials. The remaining challenges of cell survival, directed differentiation, angiogenesis, and metabolic exchange are far from trial and need to be addressed. Three-dimensional-printed materials will remain a biomaterials and engineering showcase unless applications in preclinical and clinical models are realized. In balance, 3D printing holds considerable promise in regenerative medicine as a unique approach to address organ shortage.
Dietary fibre intake has been suggested to reduce blood glucose levels in diabetic patients, particularly when glycosylated Hb (HbA1c) levels are high. In the present study, we used a quantile regression (QR) approach to characterise the possible heterogeneous associations of dietary fibre intake with HbA1c levels in Chinese diabetic patients. A total of 497 diabetic patients participated in the baseline survey in 2006 and in the follow-up survey in 2011, both of which were conducted in Pudong New Area of Shanghai, China. Structured in-person interviews were conducted to collect information on demographic characteristics and lifestyle factors. Dietary intake was assessed using a validated FFQ. Blood samples were collected during the interviews for biochemical assays. QR models were used to examine the heterogeneous associations of dietary factors with HbA1c levels. A significant marginal association of insoluble dietary fibre intake with subsequent HbA1c levels was observed only when the HbA1c level was over 6·8 %. The associations appeared to be greater when the quantile levels of HbA1c were higher. The coefficient estimates were − 0·174 (95 % CI − 0·433, − 0·025) at the quantile of 0·60, − 0·200 (95 % CI − 0·306, − 0·008) at 0·70, − 0·221 (95 % CI − 0·426, − 0·117) at 0·80, and − 0·389 (95 % CI − 0·516, − 0·018) at 0·90. A similar pattern was observed for the associations of dietary glycaemic index (GI) value with HbA1c levels. In conclusion, the present results indicate that the associations of insoluble dietary fibre intake and GI value with subsequent HbA1c levels depend on glycaemic control status in Chinese diabetic patients. More studies are required to confirm our findings.
Celestial navigation is an important type of autonomous navigation technology which could be used as an alternative to Global Navigation Satellite Systems (GNSS) when a vessel is at sea. After several centuries of development, a variety of astronomical vessel position (AVP) determination methods have been invented, but the basic concepts of these methods are all based on angular observations with a device such as a sextant, which has disadvantages including low accuracy, manual operation, and a limited period of observation. This paper proposes a new method that utilises a fisheye camera to image the celestial bodies and horizon simultaneously. Then, we calculate the obliquity of the fisheye camera's principal optical axis according to the image coordinates of the horizon. Next, we calculate the altitude of the celestial bodies according to the image coordinates of the celestial bodies and the obliquity. Finally, the AVP is determined by the altitudes according to the robust estimation method. Experimental results indicate that this method not only could realize automation and miniaturization of the AVP determination system, but could also greatly improve the efficiency of celestial navigation.