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We aimed to describe the clinical features in coronavirus disease 2019 (COVID-19) cases. We studied 134 critically ill COVID-19 cases from 30 December 2019 to 20 February 2020 in an intensive care unit (ICU) at Wuhan Jinyintan Hospital. Demographics, underlying diseases, therapy strategies and test results were collected and analysed from patients on admission, admission to the ICU and 48 h before death. The non-survivors were older (65.46 (s.d. 9.74) vs. 46.45 (s.d. 11.09)) and were more likely to have underlying diseases. The blood group distribution of the COVID-19 cases differed from that of the Han population in Wuhan, with type A being 43.85%; type B, 26.92%; type AB, 10% and type O, 19.23%. Non-survivors tend to develop more severe lymphopaenia, with higher C-reactive protein, interleukin-6, procalcitonin, D-dimer levels and gradually increased with time. The clinical manifestations were non-specific. Compared with survivors, non-survivors more likely to have organ function injury, and to receive mechanical ventilation, either invasively or noninvasively. Multiple organ failure and secondary bacterial infection in the later period is worthy of attention.
Renal fibrosis is common especially in the elderly population. Recently, we found that vitamin D deficiency caused prostatic hyperplasia. This study aimed to investigate whether vitamin D deficiency promotes renal fibrosis and functional impairment. All mice except controls were fed with vitamin D-deficient (VDD) diets, beginning from their early life. The absolute and relative kidney weights on postnatal week 20 were decreased in VDD diet-fed male pups but not in female pups. A mild pathological damage was observed in VDD diet-fed male pups but not in females. Further analysis showed that VDD-induced pathological damage was aggravated, accompanied by renal dysfunction in 40-week-old male pups. An obvious collagen deposition was observed in VDD diet-fed 40-week-old male pups. Moreover, renal α-smooth muscle actin (α-SMA), a marker of epithelial–mesenchymal transition (EMT), and Tgf-β mRNA were up-regulated. The in vitro experiment showed that 1,25-dihydroxyvitamin D3 alleviated transforming growth factor-β1 (TGF-β1)-mediated down-regulation of E-cadherin and inhibited TGF-β1-evoked up-regulation of N-cadherin, vimentin and α-SMA in renal epithelial HK-2 cells. Moreover, 1,25-dihydroxyvitamin D3 suppressed TGF-β1-evoked Smad2/3 phosphorylation in HK-2 cells. These results provide experimental evidence that long-term vitamin D deficiency promotes renal fibrosis and functional impairment, at least partially, through aggravating TGF-β/Smad2/3-mediated EMT in middle-aged male mice.
With the popularization of carbon and nitrogen stable-isotope analysis methods used on archaeological samples from Xinjiang, the ancient paleodiet there has been revealed. However, research about isotopic analysis combined with environmental factors is rare, especially in such a variable and complex climate as that of the Tianshan region. We systematically analyzed the δ13C and δ15N results from animals and humans for dietary reconstruction of nomadic pastoralists from the Tianshan region during 3900–1200 cal BP. The δ13C and δ15N values for animals (sheep/goat, horse and cattle; n = 57) have a wide range from –20.8‰ to –14.7‰ for δ13C (–19.2 ± 1.0‰) and 3.2‰ to 9.9‰ for δ15N (7.0 ± 1.2‰). The δ13C and δ15N values from humans range from –19.6 to –12.3‰ (–16.0 ± 1.5‰) and 7.1 to 16.7‰ (–13.6 ± 1.5‰), respectively. The animal δ15N results indicate that the dry environment in the Tianshan region may result in elevated δ15N values. Synthesizing animal and human isotope results suggests that the inhabitants engaged in mobile herding economies subsidized with crops and wild animal meat from the Tianshan Mountains. In conclusion, we found that the regional environment closely relates to crop types, and temporal climate change has an effect on human dietary structure. Therefore, climate condition cannot be ignored when studying human paleodiet.
The effect of holly polyphenols (HP) on intestinal inflammation and microbiota composition was evaluated in a piglet model of lipopolysaccharide (LPS)-induced intestinal injury. A total of twenty-four piglets were used in a 2 × 2 factorial design including diet type and LPS challenge. After 16 d of feeding with a basal diet supplemented with or without 250 mg/kg HP, pigs were challenged with LPS (100 μg/kg body weight) or an equal volume of saline for 4 h, followed by analysis of disaccharidase activities, gene expression levels of several representative tight junction proteins and inflammatory mediators, the SCFA concentrations and microbiota composition in intestinal contents as well as proinflammatory cytokine levels in plasma. Our results indicated that HP enhanced intestinal disaccharidase activities and reduced plasma proinflammatory cytokines including TNF-α and IL-6 in LPS-challenged piglets. Moreover, HP up-regulated mRNA expression of intestinal tight junction proteins such as claudin-1 and occludin. In addition, bacterial 16S rRNA gene sequencing showed that HP altered hindgut microbiota composition by enriching Prevotella and enhancing SCFA production following LPS challenge. These results collectively suggest that HP is capable of alleviating LPS-triggered intestinal injury by improving intestinal disaccharidase activities, barrier function and SCFA production, while reducing intestinal inflammation.
Drug use disorders are an important issue worldwide. Systematic attempts to estimate the global incidence of drug use disorders are rare. We aimed to determine the incidence of drug use disorders and their trends.
We obtained the annual incident cases and age-standardised incidence rate (ASR) of drug use disorders from 1990 to 2017 using the Global Health Data Exchange query tool. The estimated annual percentage changes of the ASR were used to quantify and evaluate the trends in the incidence rate. Gaussian process regression and the Pearson's correlation coefficient were used to assess the relationship between the ASR and socio-demographic index (SDI).
The number of drug use disorders’ cases increased by 33.5% from 1990 to 2017 globally, whereas the ASR exhibited a stable trend. The ASR was higher in men than in women. Most cases (53.1%) of drug use disorders involved opioid. A positive association (ρ=0.35, p < 0.001) was found between ASR and SDI. Teenagers aged 15–19 years had the highest incidence rate.
The incident cases of drug use disorders were increasing, but the incidence rate did not change significantly from 1990 to 2017. Current preventive measures and policies for drug use disorders might have little effect. The present results suggest that future strategies should focus on men, teenagers and high-risk regions in order to improve the current status of drug use disorders.
Wire-shaped supercapacitors (WSSCs) hold great promise in portable and wearable electronics. Herein, a novel kind of high-performance coaxial WSSCs has been demonstrated and realized by scrolling porous carbon dodecahedrons/Al foil film electrode on vertical FeOOH nanosheets wrapping carbon fiber tows (FeOOH NSs/CFTs) yarn electrode. Remarkably, ionogel is utilized as solid-state electrolyte and exhibits a high thermal/electrochemical stability, which effectively ensures the great reliability and high operating voltage of coaxial WSSCs. Benefiting from the intriguing configuration, the coaxial WSSCs with superior flexibility act as efficient energy storage devices and exhibit low resistance, high volumetric energy density (3.2 mW h/cm3), and strong durability (82% after 10,000 cycles). Importantly, the coaxial WSSCs can be effectively recharged by harvesting sustainable wind source and repeatedly supply power to the lamp without a decline of electrochemical performance. Considering the facile fabrication technology with an outstanding performance, this work has paved the way for the integration of sustainable energy harvesting and wearable energy storage units.
Existing data on folate status and hepatocellular carcinoma (HCC) prognosis are scarce. We prospectively examined whether serum folate concentrations at diagnosis were associated with liver cancer-specific survival (LCSS) and overall survival (OS) among 982 patients with newly diagnosed, previously untreated HCC, who were enrolled in the Guangdong Liver Cancer Cohort (GLCC) study between September 2013 and February 2017. Serum folate concentrations were measured using chemiluminescent microparticle immunoassay. Cox proportional hazards models were performed to estimate hazard ratios (HR) and 95 % CI by sex-specific quartile of serum folate. Compared with patients in the third quartile of serum folate, patients in the lowest quartile had significantly inferior LCSS (HR = 1·48; 95 % CI 1·05, 2·09) and OS (HR = 1·43; 95 % CI 1·03, 1·99) after adjustment for non-clinical and clinical prognostic factors. The associations were not significantly modified by sex, age at diagnosis, alcohol drinking status and Barcelona Clinic Liver Cancer (BCLC) stage. However, there were statistically significant interactions on both multiplicative and additive scale between serum folate and C-reactive protein (CRP) levels or smoking status and the associations of lower serum folate with worse LCSS and OS were only evident among patients with CRP > 3·0 mg/l or current smokers. An inverse association with LCSS were also observed among patients with liver damage score ≥3. These results suggest that lower serum folate concentrations at diagnosis are independently associated with worse HCC survival, most prominently among patients with systemic inflammation and current smokers. A future trial of folate supplementation seems to be promising in HCC patients with lower folate status.
A novel and highly efficient Ag3VO4/C3N4/reduced TiO2 microsphere composite was obtained through a hydrothermal and depositional process. The microstructure, individual components with different proportions, and optical properties of the ternary nanocomposites were intensively studied. The prepared ternary composites exhibited superior photocatalytic performance of degradation of methylene blue compared with single component and S1 (C3N4/reduced TiO2) binary composites, demonstrating that the introduction of Ag3VO4 into g-C3N4/r-TiO2 can effectively improve the photocatalytic activity. Recycling experiments confirmed that the nanocomposites exhibited superior cycle performance. The enhanced capability could be attributed to a synergetic effect including the formation of heterojunction, large surface area, improved light absorption, matched energy band structure, and the improved separation efficiency of photogenerated charges coming from dual Z-scheme structure. Particularly, the introduction of Ag3VO4 makes the dual Z-scheme charge transfer pathway completed with improved separation efficiency and stronger redox ability of photogenerated electrons and holes. The work provides a promising method to develop a new dual Z-scheme photocatalytic system to remove environmental pollutant.
This study presents an optimal design procedure including topology optimization and size–shape optimization methods to maximize mechanical advantage (which is defined as the ratio of output force to input force) of the synthesized compliant mechanism. The formulation of the topology optimization method to design compliant mechanisms with multiple output ports is presented. The topology-optimized result is used as the initial design domain for subsequent size–shape optimization process. The proposed optimal design procedure is used to synthesize an adaptive compliant gripper with high mechanical advantage. The proposed gripper is a monolithic two-finger design and is prototyped using silicon rubber. Experimental studies including mechanical advantage test, object grasping test, and payload test are carried out to evaluate the design. The results show that the proposed adaptive complaint gripper assembly can effectively grasp irregular objects up to 2.7 kg.
Multi-pass warm rolling with falling temperature was proposed and investigated to obtain AZ31 Mg alloy sheets with a fine-grained microstructure. The results indicated that the grain microstructure of AZ31 alloy sheets was successfully refined from 22.1 to 4.5 μm after multi-pass warm rolling with falling temperature and annealing. Compared to the as-received sheet, the multi-pass warm rolled sheets in annealed condition exhibited weaker (0001) basal texture intensity, which resulted in the significantly increased Schmid factor of 〈a〉 basal slip. After multi-pass warm rolling with falling temperature, the rolled sheets in annealed condition also exhibited much better mechanical properties, e.g., higher tensile strength, larger fracture elongation, and higher Erichsen value, especially the IE of 8-pass warm rolled sheet in annealed condition was significantly increased by ∼33% under the same thickness, which could be attributed to the refined grain microstructure and the weakened basal texture.
TiO2 nanomaterials with platelet or nanosheet morphologies can offer improved properties for photocatalytic applications, but established methods to produce them typically require structure-directing agents since anatase-phase TiO2 does not have a layered structure. In the present work, the preparation of TiO2 nanosheets by the chemical oxidation of TiS2 nanosheets is demonstrated. Electrochemical exfoliation of bulk TiS2 into TiS2 nanosheets, followed by the hydrothermal treatment at 180 °C for 14 h is performed. The results show that polycrystalline TiO2 nanosheets with the anatase structure are formed, and that the nanosheet morphology can still be maintained after the hydrothermal treatment. The TiO2 nanosheets show good photocatalytic activity for the degradation of methylene blue, but the performance is negatively affected by the residual carbon black that was needed in the TiS2 electrode to enable electrochemical exfoliation. These results show that conversion of TiS2 nanosheets to TiO2 nanosheets is a promising synthetic strategy but highlights how the interfacial properties of the obtained materials could be affected by ancillary components in the preparation method.
Extant spillover literature explains domestic firms' productivity change mainly by the presence and attributes of foreign direct investment. In contrary, this paper, by adopting a routine-based model of absorptive capacity, intends to explore how domestic firms absorb spillovers over time. Based on a qualitative study of a domestic firm in China's silicone adhesive industry, the findings show that unbounded by geographical constraints, domestic firms enact their external absorptive capacity routines to actively search for spillovers from multinational enterprises (MNEs) at both national and international levels. Moreover, rather than searching for what is available, domestic firms are selective for spillovers that are coherent with their business strategies. The most unexpected finding is that domestic firms diligently acquire spillovers from MNEs and from local competitors in combination. Spillovers acquired from local competitors are used to increase the inferential accuracy of spillovers acquired from MNEs about strategic successes. Further, instead of absorbing spillovers from MNEs which pose moderate technology gaps, domestic firms target at MNEs which exhibit wider technology gaps, and undertake organizational learning and develop complementary assets to enhance their internal absorptive capacity routines. Socially enabling mechanisms are found to facilitate domestic firms' absorption of spillovers by employee turnover.
Several studies have suggested that higher carotenoid levels may be beneficial for atherosclerosis patients, but few studies have examined this relationship in the Chinese population. This cross-sectional study examined the association between the levels of carotenoids in diet and serum and carotid intima–media thickness (IMT) in Chinese adults aged 50–75 years in Guangzhou, China. Dietary intake was assessed using a FFQ. HPLC was used to assay the serum concentrations of α-carotene, β-carotene, lutein+zeaxanthin, β-cryptoxanthin and lycopene. The IMT at the common carotid artery (CCA) and bifurcation of the carotid artery was measured by B-mode ultrasound. A total of 3707 and 2947 participants were included in the analyses of dietary and serum carotenoids. After adjustment for demographic, socio-economic and lifestyle factors, all the serum carotenoids levels except lycopene were found to be inversely associated with the IMT at the CCA and bifurcation (Ptrend<0·001 to 0·013) in both men and women. The absolute mean differences in the IMT between the subjects in the extreme quartiles of serum carotenoid levels were 0·034 mm (α-carotene), 0·037 mm (β-carotene), 0·032 mm (lutein+zeaxanthin), 0·030 mm (β-cryptoxanthin), 0·015 mm (lycopene) and 0·035 mm (total carotenoids) at the CCA; the corresponding values were 0·025, 0·053 0·043, 0·050, 0·011 and 0·042 mm at the bifurcation. The favourable associations were also observed between dietary carotenoids (except lycopene) and the CCA IMT. In conclusion, elevated carotenoid levels in diet and serum are associated with lower carotid IMT values (particular at the CCA) in Chinese adults.
A coaxial-output rolled strip pulse-forming line (RSPFL) with a dry structure is researched for the purpose of miniaturization and all-solid state of pulse-forming lines (PFL). The coaxial-output RSPFL consists of a coaxial-output electrode (COE) and a rolled strip line (RSL). The COE is characterized by quasi-coaxial structure, making the output pulse propagate along the axial direction with a small output inductance. The RSL is rolled on the COE, whose transmission characteristics are analyzed theoretically. It shows that the RSL can be regarded as a planar strip line when the rolling radius of the strip line is larger than 60 times of the thickness of the insulation dielectric layer of RSL. CST modeling was carried out to simulate the discharging characteristic of the coaxial-output RSPFL. It shows that the coaxial-output RSPFL can deliver a discharging pulse with a rise time <6 ns when the impedance of the RSL matches that of the COE, which confirms the theoretical analysis. A prototype of the coaxial-output RSPFL was developed. A 49-kV discharging pulse on a matched load was achieved when it was charged to 100 kV. The discharging waveform has a pulse width of 32 ns, with a rise time of 6 ns, which is consistent with the simulation waveform. An energy-storage density of 1.9 J/L was realized in the coaxial-output RSPFL. By the method of multi-stage connection in series, a much higher output voltage is convenient to be obtained.
The objective of this Research Communication was to use polymerase chain reaction-single stranded conformational polymorphism (PCR-SSCP) analysis to investigate a region of the bovine TLR4 gene (TLR4) in pasture-fed New Zealand (NZ) Holstein-Friesian × Jersey (HF × J) cross dairy cows and to determine whether gene variation was associated with milk production traits. Genetic variation was observed, with two variants (A and B) containing a single nucleotide polymorphism (SNP) (c.2021C/T) that was non-synonymous and putatively results in a p.Thr674Ile substitution in the transmembrane/cytoplasmic domain of TLR4. Variant A was associated with higher milk yields, but lower milk fat percentages, whereas B was associated with lower milk yields, but higher fat and protein percentages. Cows of genotype AA produced more milk than AB or BB cows, but the milk produced by AA cows contained less fat than AB or BB cows.
We identified human paleodietary changes from inhabitants of the Guanzhong basin since 8000 BP, based on published carbon and nitrogen isotopic measurements on bones, fauna and plant remains. We also directly measured 14C ages, δ13C and δ15N values from bones unearthed at the Zhouyuan site, west of Guanzhong, in order to reconstruct paleodietary changes of the ancient inhabitants. We found that during the Laoguantai period, animal foods were the main source of nourishment with supplementary plant-derived foods. After this period, plant-derived foods became the main food source, with supplementary animal sources. The development of dry farming led to increased consumption of foxtail millet and broomcorn millet. This trend persisted and marked a fundamental shift from hunting, gathering, and fishing to farming and animal domestication. The dietary trends of the ancient inhabitants also show pronounced regional differences through time. The use of domestic animals was proportionally higher in the eastern part of the Guanzhong region, while wild animals were more common in the west.
The Myanmar snub-nosed monkey Rhinopithecus strykeri was discovered in 2010 on the western slopes of the Gaoligong Mountains in the Irrawaddy River basin in Myanmar and subsequently in the same river basin in China, in 2011. Based on 2 years of surveying the remote and little disturbed forest of the Gaoligong Mountains National Nature Reserve in China, with outline transect sampling and infrared camera monitoring, a breeding group comprising > 70 individuals was found on the eastern slopes of the Gaoligong Mountains in the Salween River Basin. Given the Critically Endangered status of this primate (a total of < 950 individuals are estimated to remain in the wild), efforts to protect the relatively undisturbed habitat of this newly discovered population and to prevent hunting are essential for the long-term survival of this species.
In this paper, an ultra-wideband (UWB) filter with a notch band using T-shaped step impedance resonator loaded with cross-shaped open stubs has been presented. The notch band is formed by utilizing intrinsic zero. The characteristics of the new quad-mode resonator have been analyzed using odd-even mode analysis method. It can be shown that it is the intrinsic zero that generates the notch band. In addition, wide tunable notch band form 5–9.3 GHz can be achieved. A UWB filter with a notch band centered at 6.25 GHz using the proposed quad-mode resonator has been designed, fabricated, and tested. Experiment results show that the attenuation in notch frequency is >22 dB while the return loss of the simulation and measurement results are 22 dB/20 dB and 14.5 dB/11.2 dB in the lower and upper passband, respectively, which illustrate that the simulation and measurement results are in agreement.