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Hypertension represents one of the most common pre-existing conditions and comorbidities in Coronavirus disease 2019 (COVID-19) patients. To explore whether hypertension serves as a risk factor for disease severity, a multi-centre, retrospective study was conducted in COVID-19 patients. A total of 498 consecutively hospitalised patients with lab-confirmed COVID-19 in China were enrolled in this cohort. Using logistic regression, we assessed the association between hypertension and the likelihood of severe illness with adjustment for confounders. We observed that more than 16% of the enrolled patients exhibited pre-existing hypertension on admission. More severe COVID-19 cases occurred in individuals with hypertension than those without hypertension (21% vs. 10%, P = 0.007). Hypertension associated with the increased risk of severe illness, which was not modified by other demographic factors, such as age, sex, hospital geological location and blood pressure levels on admission. More attention and treatment should be offered to patients with underlying hypertension, who usually are older, have more comorbidities and more susceptible to cardiac complications.
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.
Using frequency-modulated continuous wave radar data from the 32nd Chinese Antarctic Research Expedition in 2015/16, subsurface profiles were obtained along an East Antarctic inland traverse from Zhongshan station to Dome A, and four distinct regions were selected to analyze the spatiotemporal variability in historical surface mass balance (SMB). Based on depth, density, and age data from ice cores along the traverse, the radar data were calibrated to yield average SMB data. The zone 49–195 km from the coast has the highest SMB (235 kg m−2 a−1). The 780–892 km zone was most affected by the Medieval Warm Period and the Little Ice Age, and the SMB during ad 1454–1836 (71 kg m−2 a−1) was only one-quarter of that in the 20th century. The SMB in the 1080–1157 km zone fluctuates the most, possibly due to erosion or irregular deposition of snow by katabatic winds in low SMB areas with surface elevation fluctuations. Dome A (1157–1236 km) has the lowest SMB (29 kg m−2 a−1) and did not decrease during Little Ice Age. Understanding the spatiotemporal variability of SMB in a larger space can help us understand the complex climate history of Antarctica.
In the current research, a 60-day experiment was conducted with the purpose of exploring the impacts of methionine on growth performance, muscle nutritive deposition, muscle fibre growth and type I collagen synthesis as well as related signaling pathway. Six diets (iso-nitrogenous) differing in methionine concentrations (2.54, 4.85, 7.43, 10.12, 12.40 and 15.11 g kg-1 diets) were fed to 540 grass carp (178.47 ± 0.36 g). Results showed (P < 0.05) that, compared with methionine deficiency, optimal level of dietary methionine (1) increased feed intake (FI), feed efficiency (FE), specific growth rate (SGR) and percentage weight gain (PWG); (2) increased fish muscle protein, lipid and free amino acid contents, and improved fish muscle fatty acid profile as well as increased protein content in part associated with TORC1/S6K1 signaling pathway; (3) increased the frequency distribution of muscle fibre with >50 µm of diameter; (4) increased type I collagen synthesis partly related to TGF-β1/Smads and CK2/TORC1 signaling pathways. In conclusion, dietary methionine improved muscle growth, which might be due to the regulation of muscle nutritive deposition, and muscle fibre growth and type I collagen synthesis related signal molecules. Finally, according to PWG and muscle collagen content, the methionine requirements for on-growing grass carp (178-626 g) were estimated to be 9.56 g kg-1 diet (33.26 g kg-1 protein of diet) and 9.28 g kg-1 diet (32.29 g kg-1 of dietary protein), respectively.
The time to positivity (TTP) of blood cultures has been considered a predictor of clinical outcomes for bacteremia. This retrospective study aimed to determine the clinical value of TTP for the prognostic assessment of patients with Escherichia coli bacteremia. A total of 167 adult patients with E.coli bacteremia identified over a 22-month period in a 3500-bed university teaching hospital in China were studied. The standard cut-off TTP was 11 h in the patient cohort. The septic shock occurred in 27.9% of patients with early TTP (⩽11 h) and in 7.1% of those with a prolonged TTP (>11 h) (P = 0.003). The mortality rate was significantly higher for patients in the early than in the late group (17.7% vs. 4.0%, P < 0.001). Multivariate analysis showed that an early TTP (OR 4.50, 95% CI 1.70–11.93), intensive care unit admission (OR 8.39, 95% CI 2.01–35.14) and neutropenia (OR 4.20, 95% CI 1.55–11.40) were independently associated with septic shock. Likewise, the independent risk factors for mortality of patients were an early TTP (OR 3.80, 95% CI 1.04–12.90), intensive care unit admission (OR 6.45; 95% CI 1.14–36.53), a Pittsburgh bacteremia score ⩾2 (OR 4.34, 95% CI 1.22–15.47) and a Charlson Comorbidity Index ⩾3 (OR 11.29, 95% CI 2.81–45.39). Overall, a TTP for blood cultures within 11 h appears to be associated with worse outcomes for patients with E.coli bacteremia.
In recent years, banded leaf sheath blight in maize (Zea mays L.) has become an important disease that seriously affects quality and yield. This paper aims to evaluate the sensitivity of Rhizoctonia solani Kuhn to thifluzamide on maize, to clarify the effect of seed coating using a thifluzamide suspension agent on safety and physiological indicators and to determine the effectiveness of control of banded leaf sheath blight in the field. In this study, the thifluzamide sensitivity of 102 strains of R. solani in maize from Shandong was determined using the mycelial growth rate method; the average half-maximal effective concentration value (EC50) was 0.086 ± 0.004 μg/ml and displayed a unimodal frequency distribution, indicating that thifluzamide had strong inhibitory activity on the mycelial growth of R. solani in maize. In an indoor pot test, the root activities under 24 g a.i./100 kg seed were found to increase by 78.01%, compared with the control. Similarly, chlorophyll content increased most significantly at this dose, by 32.3%. Thifluzamide (FS) could significantly increase the per-plot yield. Among the examined dosages, 48 g a.i./100 kg seed had the most significant treatment effect, with the yield rate increasing by 15.7% and 14.1%, respectively, in 2017 and 2018 compared with the control. The field effectiveness against banded leaf sheath blight in maize was highest at the dosage of 48 g a.i./100 kg seed for a seed dressing with thifluzamide (FS). These results indicate that thifluzamide has enormous potential for controlling banded leaf sheath blight in maize.
The interaction of a shock wave and a water droplet embedded with a vapour cavity is experimentally investigated in a shock tube for the first time. The vapour cavity inside the droplet is generated by decreasing the surrounding pressure to the saturation pressure, and an equilibrium between the liquid phase and the gas phase is obtained inside the droplet. Direct high-speed photography is adopted to capture the evolution of both the droplet and the vapour cavity. The formation of a transverse jet inside the droplet during the cavity-collapse stage is clearly observed. Soon afterwards, at the downstream pole of the droplet, a water jet penetrating into the surrounding air is observed during the cavity-expansion stage. The evolution of the droplet is strongly influenced by the evolution of the vapour cavity. The phase change process plays an important role in vapour cavity evolution. The effects of the relative size and eccentricity of the cavity on the movement and deformation of the droplet are presented quantitatively.
Monolayer (ML) molybdenum disulfide (MoS₂) is a novel 2-dimensional (2D) semiconductor whose properties have many applications in devices. Despite its potential, ML MoS₂ is limited in its use due to its degradation under exposure to ambient air. Therefore, studies of possible degradation prevention methods are important. It is well established that air humidity plays a major role in the degradation. In this paper, we investigate the effects of substrate hydrophobicity on the degradation of chemical vapor deposition (CVD) grown ML MoS2. We use optical microscopy, atomic force microscopy (AFM), and Raman mapping to investigate the degradation of ML MoS2 grown on SiO2 and Si3N4 that are hydrophilic and hydrophobic substrates, respectively. Our results show that the degradation of ML MoS₂ on Si3N4 is significantly less than the degradation on SiO2. These results show that using hydrophobic substrates to grow 2D transition metal dichalcogenide ML materials may diminish ambient degradation and enable improved protocols for device manufacturing.
Emerging evidence has been revealed that high fat diet (HFD) correlate with insulin resistance (IR) which could be induced by endoplasmic reticulum stress (ERS). Recently, obesity or HFD induced nonalcoholic fatty liver disease (NAFLD) could promote alteration of iron metabolism. Disorder of iron metabolism have been linked to unnormal metabolism of glucose and lipid. Herein, we investigated the effect of impaired iron homeostasis on hepatic IR, focusing on ferritinophagy. Male C57/6J mice were administered with HFD (60% energy from fat) or LFD (10% energy from fat) for 10 weeks (n = 10), and Palmitic acid (PA)-insulin treated HepG2 cells were also established. Hepatic IR as evidenced by increased hepatic steatosis and decreased of p-AKT (48%, p < 0.0005), p-GSK-3β (34%, p < 0.05) in the liver of HFD mice. In addition, decreased iron level and expression NCOA4, as well as increased up-regulation of IRE1α and EIF2α were observed in HFD liver. By using desferrioxamine (DFO) and ferric ammonium citrate (FAC), we examined iron level on IRE1α and EIF2α. And glucose uptake assay shown that FAC supplementation, and ERS inhibitors of 4-PBA and STF could improve the glucose uptake of HepG2 cells in the presence of PA. Furthermore, we evaluated the glucose uptake of HepG2 cells incubated with adenovirus which mediated overexpression of NCOA4, FAC, 4-PBA (ERS inhibitor) or STF (IRE1 inhibitor). Taken together, deficiency of iron induced by impaired ferritinophagy induced hepatic IR, partly by aggravating hepatic ERS, especially IRE1 signal pathway in vivo and vitro. These findings provide evidence and new insight for therapeutic strategy of iron deficiency in NAFLD.
The present study investigated the effects of condensed tannins (CT) on intestinal immune function in on-growing grass carp (Ctenopharyngodon idella). A total of 540 healthy grass carp were fed six diets containing different levels of CT (0, 10·00, 20·00, 30·00, 40·00 and 50·00 g/kg diet) for 70 d and then challenged with Aeromonas hydrophila for 14 d. The results showed that, compared with the control group, dietary CT (1) induced intestinal histopathological lesions and aggravated enteritis; (2) decreased lysozyme and acid phosphatase activities, complement 3 (C3), C4 and IgM contents and down-regulated the Hepcidin, liver-expressed antimicrobial peptide (LEAP)-2A, LEAP-2B, Mucin2 and β-defensin-1 mRNA levels in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI) (P < 0·05); (3) down-regulated the mRNA levels of anti-inflammatory cytokines transforming growth factor (TGF)-β1, TGF-β2 (not in MI and DI), IL-4/13A (not IL-4/13B), IL-10 and IL-11 partly correlated with target of rapamycin (TOR) signalling; and (4) up-regulated the mRNA levels of pro-inflammatory cytokines interferon-γ2, IL-1β, IL-6, IL-8 (not in PI), IL-12p35, IL-12p40, IL-15 and IL-17D partly related to NF-κB signalling in the intestine of on-growing grass carp. Overall, the results indicated that CT could impair the intestinal immune function, and its potential regulation mechanisms were partly associated with the TOR and NF-κB signalling pathways. Finally, based on the percentage weight gain and enteritis morbidity, the maximum allowable levels of CT for on-growing grass carp (232·22–890·11 g) were estimated to be 18·6 and 17·4 g/kg diet, respectively.
Severe trauma can lead to amputation of limbs. There is no golden standard or comprehensive evaluation indicator for amputation. It is difficult for the primary rescue organization to focus on the most essential indicators and to determine whether to perform amputation or take proper operation.
For medical staff in first-line medical teams for disaster relief or in a common primary hospital, what indicators should they focus on to keep the patient’s limbs when they receive wounded patients with severe trauma?
A retrospective case-control study was performed based on the patients with severe trauma from January 2013 through December 2018 in the emergency department of Southwest Hospital (Shapingba District, Chongqing, China), a Level I trauma center. A total of 165 cases were divided into amputation group (n = 79) and non-amputation control group (n = 86), which had severe skin and muscle injury but without amputation. The causes of trauma and the special cases were analyzed. Binary logistic regression models were used to find the essential indicators for amputation.
Neurovascular injury with delayed treatment was the most decisive indicator leading to amputation, and time phase was also important for limb salvage. Preliminary treatment of disaster victims and patients with severe trauma should focus on neurovascular status and timely delivery.
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.
Previous studies in schizophrenia revealed abnormalities in the cortico-cerebellar-thalamo-cortical circuit (CCTCC) pathway, suggesting the necessity for defining thalamic subdivisions in understanding alterations of brain connectivity.
To parcellate the thalamus into several subdivisions using a data-driven method, and to evaluate the role of each subdivision in the alterations of CCTCC functional connectivity in patients with schizophrenia.
There were 54 patients with schizophrenia and 42 healthy controls included in this study. First, the thalamic structural and functional connections computed, based on diffusion magnetic resonance imaging (MRI, white matter tractography) and resting-state functional MRI, were clustered to parcellate thalamus. Next, functional connectivity of each thalamus subdivision was investigated, and the alterations in thalamic functional connectivity for patients with schizophrenia were inspected.
Based on the data-driven parcellation method, six thalamic subdivisions were defined. Loss of connectivity was observed between several thalamic subdivisions (superior-anterior, ventromedial and dorsolateral part of the thalamus) and the sensorimotor system, anterior cingulate cortex and cerebellum in patients with schizophrenia. A gradual pattern of dysconnectivity was observed across the thalamic subdivisions. Additionally, the altered connectivity negatively correlated with symptom scores and duration of illness in individuals with schizophrenia.
The findings of the study revealed a wide range of thalamic functional dysconnectivity in the CCTCC pathway, increasing our understanding of the relationship between the CCTCC pathway and symptoms associated with schizophrenia, and further indicating a potential alteration pattern in the thalamic nuclei in people with schizophrenia.
Ring artifacts are undesirable and complicate the analysis and interpretation of microstructures in synchrotron X-ray microtomography. Here, we propose a new method to improve the image quality of an object by removing the ring artifacts and investigate the efficiency of this process with tomographic images of a dried Tenebrio molitor. In this method, before the tomographic reconstruction, ring artifacts were identified and located in the sinograms as line artifacts. Then, the identified line artifacts were corrected as single point noise via image processing of the original projections. Eventually, the corresponding line artifacts were removed, resulting in reduced ring artifacts in the reconstructed tomographic images. Simulations verified the efficiency of the proposed method. This method was successfully applied for the structural analysis of the insect T. molitor, showing superior performance in reducing ring artifacts in the tomographic image without noticeable loss of structural information.
This study aimed to investigate the impacts of dietary threonine on intestinal immunity and inflammation in juvenile grass carp. Six iso-nitrogenous semi-purified diets containing graded levels of threonine (3·99–21·66 g threonine/kg) were formulated and fed to fishes for 8 weeks, and then challenged with Aeromonas hydrophila for 14 d. Results showed that, compared with optimum threonine supplementation, threonine deficiency (1) decreased the ability of fish against enteritis, intestinal lysozyme activities (except in the distal intestine), acid phosphatase activities, complement 3 (C3) and C4 contents and IgM contents (except in the proximal intestine (PI)), and it down-regulated the transcript abundances of liver-expressed antimicrobial peptide (LEAP)-2A, LEAP-2B, hepcidin, IgZ, IgM and β-defensin1 (except in the PI) (P<0·05); (2) could up-regulate intestinal pro-inflammatory cytokines TNF-α, IL-1β, IL-6, IL-8 and IL-17D mRNA levels partly related to NF-κB signalling; (3) could down-regulate intestinal anti-inflammatory cytokine transforming growth factor (TGF)-β1, TGF-β2, IL-4/13A (not IL-4/13B) and IL-10 mRNA levels partly by target of rapamycin signalling. Finally, on the basis of the specific growth rate, against the enteritis morbidity and IgM contents, the optimum threonine requirements were estimated to be 14·53 g threonine/kg diet (4·48 g threonine/100 g protein), 15.05 g threonine/kg diet (4·64 g threonine/100 g protein) and 15·17 g threonine/kg diet (4·68 g threonine/100 g protein), respectively.
The present study investigated the effects of dietary vitamin A on immune function in the proximal intestine (PI), mid intestine (MI) and distal intestine (DI) of young grass carp (Ctenopharyngodon idella). Fish were fed graded levels of dietary vitamin A for 10 weeks, and then a challenge test using an injection of Aeromonas hydrophila was conducted for 14 d. The results showed that, compared with the optimum vitamin A level, vitamin A deficiency significantly decreased fish growth performance, increased enteritis morbidity, decreased intestinal innate humoral immune response and aggravated intestinal inflammation. However, liver-expressed antimicrobial peptide 2A/B mRNA in the DI and IL-6, IL-17D, IL-10, transforming growth factor (TGF)-β1 and TGF-β2 mRNA in the PI were not affected by vitamin A levels. Meanwhile, vitamin A deficiency disturbed inflammatory cytokines in the PI, MI and DI, which might be partly linked to p38 mitogen-activated protein kinase (p38MAPK) signalling and NF-κB canonical signalling pathway (IκB kinase β (IKKβ), IKKγ, inhibitor of κBα, NF-κB p65 and c-Rel) rather than NF-κB non-canonical signalling pathway (NF-κB p52 and IKKα). However, the signalling molecules NF-κB p65 and p38MAPK did not participate in regulating cytokines in the PI. These results suggested that vitamin A deficiency decreased fish growth and impaired intestinal immune function, and that different immune responses in the PI, MI and DI were mediated partly by NF-κB canonical signalling and p38MAPK signalling pathways. On the basis of percentage of weight gain, to protect fish against enteritis morbidity and acid phosphatase activity, the optimum dietary vitamin A levels were estimated to be 0·664, 0·707 and 0·722 mg /kg, respectively.
In this work, temperature-dependent optical properties of a series of AlN thin films with different thickness are studied by spectroscopic ellipsometry (SE) ranging from 300 to 825K. The fitted refractive index at 300K is in good agreement with the reported by others, which confirms the high accuracy of the optical model used in this work. The degradation of the absorption properties and the decrease of the bandgap become more pronounced with temperature increases above 475K. A larger change of bandgap at elevated temperature is observed for the thinner AlN epi-layer (300nm) than the thicker ones (404nm). This can be attributed to the poor surface morphologies and crystal qualities in the thinner AlN epi-layer.
Facilitated by recent establishment of terrestrial networks and satellite constellations of Automatic Identification System (AIS) receivers, ship trajectories are becoming increasingly available and the size of recorded trajectories is getting larger. Large sets of trajectories create problems of storing, transmitting and processing data. Using appropriate methods, an accurate representation of the original trajectories can be obtained by compressing redundant information, while maintaining the main characteristic elements. In this paper, a new scheme and the implementation of the Douglas-Peucker (DP) algorithm are presented, which can simplify AIS trajectories by extracting characteristic points. As for the simplification threshold, the solo parameter of the DP algorithm, a new AIS-based minimum ship domain evaluation method is proposed and acts as criteria for simplification threshold determination. Finally, a validation is made to examine the effectiveness of the DP simplification algorithm and the rationality of the simplification threshold. The result indicates that the DP algorithm can simplify AIS trajectories effectively; the simplification threshold is scientific and reasonable.