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To compare the epidemiologic features (e.g. settings and transmission mode) and patient clinical characteristics associated with outbreaks of different norovirus (Nov) strains, we retrospectively analysed data of Nov outbreaks occurring in Guangzhou, China from 2012 to 2018. The results suggested that outbreaks of Nov GII.2, GII.17 and GII.4 Sydney exhibited different outbreak settings, transmission modes and symptoms. GII.2 outbreaks mainly occurred in kindergartens, elementary and high schools and were transmitted mainly through person-to-person contact. By contrast, GII.4 Sydney outbreaks frequently occurred in colleges and were primarily associated with foodborne transmission. Cases from GII.2 and GII.17 outbreaks reported vomiting more frequently than those from outbreaks associated with GII.4 Sydney.
An experiment was conducted to determine the effects of supplementing different amounts of daidzein in a diet on the growth performance, blood biochemical parameters and meat quality of finishing beef cattle. Thirty finishing Xianan steers were distributed in three groups equilibrated by weight and fed three different dietary treatments (concentrate ratio = 80%): (1) control; (2) 500 mg/kg daidzein and (3) 1000 mg/kg daidzein, respectively. Steers were slaughtered after an 80-day feeding trial. Results showed that daidzein supplementation had no effect on the final body weight, average daily gain and feed conversion rate of steers. Steers fed with 1000 mg/kg daidzein had greater dry matter intake than those fed with control diets. Compared with the control group, the 1000 mg/kg daidzein group had a higher fat thickness, lower shear force and lightness. The pH, drip loss, cooking loss, redness (a*), yellowness (b*), moisture, ash, crude protein and intramuscular fat of the Longissimus dorsi muscle were unaffected by daidzein supplementation. Compared with the control group, the 1000 mg/kg daidzein group significantly increased the serum concentrations of insulin, free fatty acid and Glutamic-pyruvic transaminase. The 500 mg/kg daidzein group significantly increased the serum concentration of tetraiodothyronine compared with the control group. Supplemental daidzein did not affect the blood antioxidant ability and blood immune parameters in serum. In conclusion, daidzein supplementation above 500 mg/day modifies feed intake and metabolic and hormonal profile, with positive and negative effects on meat quality.
The study investigated whether different dietary energy and protein sources affect laying performance, antioxidant status, fresh yolk fatty acid profile and quality of salted yolks in laying ducks. In all, 360 19-week-old Longyan ducks were randomly assigned to four diets in a factorial arrangement (2×2). The four diets consisted of two energy sources, corn (CO) or sorghum (SO) and two protein sources, soybean meal (SM) and rapeseed meal with corn distillers dried grains with solubles (RMD), and each treatment contained six replicates of 15 birds each. The experimental diets were isocaloric (metabolizable energy, 10.84 MJ/kg) and isonitrogenous (CP, 17%). The results showed that egg production, average egg weight, egg mass and feed conversion ratio were not affected by diets (P>0.05). Plasma contents of reduced glutathione (GSH), GSH/oxidized glutathione and total antioxidant capacity were lower (P<0.05) in ducks fed the RMD diets compared with those fed SM diets with a substantial increase (P=0.006) in plasma content of malondialdehyde (MDA). Egg yolks from ducks fed SO diets had higher proportions of polyunsaturated fatty acids (PUFA) and lower saturated and monounsaturated fatty acids compared with CO diets (P<0.001). Similarly, ducks fed RMD diets had a higher content of PUFA and n-6/n-3 ratio in fresh yolks (P<0.001), and increased salted yolk MDA, carbonylated proteins content and incidence of hard salted yolks (P<0.05) compared with SM diets. Scanning electron microscopy showed that salted yolks contained rougher polyhedral granules and fewer fat droplets, and were surrounded with a layer of bunchy fibers in ducks fed SO+RMD than those fed CO+SM diet. In conclusion, the current study showed that feeding laying ducks with diets containing SO or RMD reduced antioxidant capacity and increased egg yolk concentrations of PUFA. It appeared that egg yolks from ducks fed these diets were more sensitive to lipid peroxidation and protein oxidation during salting, and reduced the quality of salted yolks.
Optimal nitrogen (N) management for maize in the film-mulched production systems that are widely used in dryland agriculture is difficult because top-dressing N is impractical. The current research determined how matching N supply and demand was achieved before and after silking stages, when single applications of controlled release urea (CRU) were combined with conventional urea in film-mulched maize production. The CRU: urea mixture was applied in a 1 : 2 or 2 : 1 ratio and all three fertilizer regimes (urea alone and CRU: urea at 1 : 2 or 2 : 1) were applied at N rates of 180 and 240 kg/ha over 2 years. The 1 : 2 CRU: urea mixture, applied once at 180 kg N/ha, was found to synchronize N supply with demand, thereby reducing N losses. The highest grain yields (11·8–12·0 t/ha), N uptake (232–239 kg/ha), N recovery (65·8–67·7%) and high net economic return were achieved with this regime. These results indicate that a single application of a mixture of CRU and urea can synchronize N supply with demand and provide higher yields and profits than conventional N fertilization in film-mulched maize systems.
MicroRNAs (miRNAs) are a class of small non-coding RNAs that negatively regulate gene expression of target messenger RNAs (mRNAs) and miRNAs have been proven to play vital roles in skeletal muscle development. The miRNA-499-5p has been reported to be negatively related with the expression of Sox6, a critical transcription factor for the maintenance of fast-twitch skeletal muscle. In this study, we amplified a length of 2012-bp mRNA that contains a 1512-bp porcine Sox6 (pSox6) 3'UTR from skeletal muscle of a Duroc×Landrace×Yorkshire pig. By luciferase reporter assay we verified that pSox6 is a target of miR-499-5p. In extensor digitorum longus and Soleus muscles of pigs, the expression levels of miR-499-5p and pSox6 mRNA were also inversely correlated. Besides, overexpression of miR-499-5p in porcine satellite cells promoted the expression of MyHC I and MyHC IIa mRNA, along with a reduction of pSox6 mRNA. Taken together, these results indicate that miR-499-5p may facilitate the oxidative myofibers formation by downregulating pSox6 expression.
In the theory research and engineering practice, more basic inflatable models are essential for the mechanical property analysis of inflatable structures. Firstly, this paper presents a model of the tapered inflatable cantilever beam based on Timoshenko's theory and analyzes its deformation under a concentrated force. Moreover, the following forces resulting from internal pressure and taper ratio are introduced into the equilibrium equations of the deformed configuration. Thus, the model is optimized compared to the existing one for a straight beam. To verify the effectiveness and the superiority of the established model, the theoretical method based on the model and FEM method are compared by adopting an example about the tapered beams. Finally, the theoretical method is applied in analyzing the influence of geometry and estimating a valid range of taper ratio. By the criterion of the same amount material area, the optimum taper ratio is obtained.
Pig farmers and veterinarians have high prevalence of methicillin-resistant Staphylococcus aureus (MRSA) due to the occupational livestock exposure, while few reported this association on slaughterhouse workers. We conducted this cross-sectional study to explore the phenotypic and molecular characteristics of S. aureus and MRSA in slaughterhouse pig-related workers and control workers in Guangdong Province, China. Participants were interviewed and provided two nasal swabs. Swabs were tested for S. aureus, and isolates were further tested for antimicrobial susceptibility, virulence genes and multi-locus sequence typing. Compared with control workers, pig-related workers have significantly higher prevalence of MRSA carriage (adjusted odd ratio (aOR) 3·70, 95% CI 1·63–8·40). The proportions of MRSA resistant to clindamycin, erythromycin, tetracycline or chloromycetin were significantly higher in pig-related workers than in control workers. The predominant phenotypes of S. aureus were resistant to penicillin, clindamycin, erythromycin and tetracycline. Three MRSA CC9 isolates with livestock-associated characteristics (resistance to tetracycline and absence of immune evasion cluster (IEC) genes) were detected in pig-related workers but not in control workers. For human-associated CCs (CC7, CC59, CC6, and CC188), there was no significant difference in IEC profile or antimicrobial resistance between the groups. These findings reveal that there may be a potential risk for livestock-to-human transmission of LA-MRSA and human-to-human transmission of human-associated MRSA.
The present work focuses on the deformation and recovery mechanisms of aged monoclinic U–Nb alloy under tension and load–unload cycle testing using in situ X-ray diffraction (XRD). The U–6.2wt% Nb (U–6.2Nb) alloy was prepared and aged at 200 °C, and then underwent tensile testing followed by the in situ XRD. The experimental results indicate that the change of diffraction peaks can serve to accurately characterize the macroscopic deformation and recovery. Compared with the as-quenched alloy, the aged U–6.2Nb alloy displays different behavior during deformation and subsequent recovery. Phase transformation competes with twin rearrangement to dominate the deformation and recovery between elastic stage and slip stage of the alloy. The lattice plane relationship between α″ and γ° during phase transformation has also been given.
Worldwide 350 million people suffer from major depression, with the majority of cases occurring in low- and middle-income countries. We examined the patterns, correlates and care-seeking behaviour of adults suffering from major depressive episode (MDE) in China.
A nationwide study recruited 512 891 adults aged 30–79 years from 10 provinces across China during 2004–2008. The 12-month prevalence of MDE was assessed by the Modified Composite International Diagnostic Interview-short form. Logistic regression yielded adjusted odds ratios (ORs) of MDE associated with socio-economic, lifestyle and health-related factors and major stressful life events.
Overall, 0.7% of participants had MDE and a further 2.4% had major depressive symptoms. Stressful life events were strongly associated with MDE [adjusted OR 14.7, 95% confidence interval (CI) 13.7–15.7], with a dose–response relationship with the number of such events experienced. Family conflict had the highest OR for MDE (18.9, 95% CI 16.8–21.2) among the 10 stressful life events. The risk of MDE was also positively associated with rural residency (OR 1.5, 95% CI 1.4–1.7), low income (OR 2.3, 95% CI 2.1–2.4), living alone (OR 2.6, 95% CI 2.3–3.0), smoking (OR 1.4, 95% CI 1.3–1.6) and certain other mental disorders (e.g. anxiety, phobia). Similar, albeit weaker, associations were observed with depressive symptoms. Among those with MDE, about 15% sought medical help or took psychiatric medication, 15% reported having suicidal ideation and 6% reported attempting suicide.
Among Chinese adults, the patterns and correlates of MDE were generally consistent with those observed in the West. The low rates of seeking professional help and treatment highlight the great gap in mental health services in China.
In this paper, a simplified lattice Boltzmann method (SLBM) without evolution of the distribution function is developed for simulating incompressible viscous flows. This method is developed from the application of fractional step technique to the macroscopic Navier-Stokes (N-S) equations recovered from lattice Boltzmann equation by using Chapman-Enskog expansion analysis. In SLBM, the equilibrium distribution function is calculated from the macroscopic variables, while the non-equilibrium distribution function is simply evaluated from the difference of two equilibrium distribution functions. Therefore, SLBM tracks the evolution of the macroscopic variables rather than the distribution function. As a result, lower virtual memories are required and physical boundary conditions could be directly implemented. Through numerical test at high Reynolds number, the method shows very nice performance in numerical stability. An accuracy test for the 2D Taylor-Green flow shows that SLBM has the second-order of accuracy in space. More benchmark tests, including the Couette flow, the Poiseuille flow as well as the 2D lid-driven cavity flow, are conducted to further validate the present method; and the simulation results are in good agreement with available data in literatures.
H9 avian influenza virus played a key role during generation of the novel H7N9 virus. A surveillance programme was conducted to assess the H9 virus in relation to the risk of H7N9 virus contamination in the environment. Risk of H7N9 virus contamination in the presence of H9 virus was higher than without (adjusted odds ratio 4·49, 95% confidence interval 3·79–5·31). Adjusted odds ratios of the H7N9 virus associated with co-presence of H9 virus and interacting factors were 4·93 (rural vs. urban area), 46·80 (live poultry markets vs. other premises), 6·86 (Huzhou vs. Hangzhou prefecture), 40·67 (year 2015 vs. 2013), and 9·63 (sewage from cleaning poultry vs. poultry faeces). Regular surveillance on gene variability of H7N9 and H9 viruses should be conducted and extra measures are needed to reduce co-circulation of H7N9 and H9 viruses in the environment.
The Universe is permeated by hot, turbulent, magnetized plasmas. Turbulent plasma is a major constituent of active galactic nuclei, supernova remnants, the intergalactic and interstellar medium, the solar corona, the solar wind and the Earth’s magnetosphere, just to mention a few examples. Energy dissipation of turbulent fluctuations plays a key role in plasma heating and energization, yet we still do not understand the underlying physical mechanisms involved. THOR is a mission designed to answer the questions of how turbulent plasma is heated and particles accelerated, how the dissipated energy is partitioned and how dissipation operates in different regimes of turbulence. THOR is a single-spacecraft mission with an orbit tuned to maximize data return from regions in near-Earth space – magnetosheath, shock, foreshock and pristine solar wind – featuring different kinds of turbulence. Here we summarize the THOR proposal submitted on 15 January 2015 to the ‘Call for a Medium-size mission opportunity in ESAs Science Programme for a launch in 2025 (M4)’. THOR has been selected by European Space Agency (ESA) for the study phase.
EVA foams, like all other polymers, also exhibit strain-rate effects and hysteresis. However, currently available approaches for predicting the mechanical response of polymeric foam subjected to an arbitrarily imposed loading history and strain-rate effect are highly limited. Especially, the strain rates in the intermediate rate domain (between 100 and 102 s–1) are extremely difficult to study. The use of data generated through the drop tower technique for implementation in constitutive equations or numerical models has not been considered in past studies. In this study, an experiment including a quasi-static compression test and drop impact tests with a high speed camera was conducted. An inverse analysis technique combined with a finite element model for material parameter identification was developed to determine the stress–strain behavior of foam at different specific strain rates. It was used in this study to simulate multiple loading and unloading cycles on foam specimens, and the results were compared with experimental measurements.
Schizophrenia patients have a higher prevalence of type 2 diabetes mellitus with impaired glucose tolerance (IGT) than normals. We examined the relationship between IGT and clinical phenotypes or cognitive deficits in first-episode, drug-naïve (FEDN) Han Chinese patients with schizophrenia.
A total of 175 in-patients were compared with 31 healthy controls on anthropometric measures and fasting plasma levels of glucose, insulin and lipids. They were also compared using a 75 g oral glucose tolerance test and the homeostasis model assessment of insulin resistance (HOMA-IR). Neurocognitive functioning was assessed using the MATRICS Consensus Cognitive Battery (MCCB). Patient psychopathology was assessed using the Positive and Negative Syndrome Scale (PANSS).
Of the patients, 24.5% had IGT compared with none of the controls, and they also had significantly higher levels of fasting blood glucose and 2-h glucose after an oral glucose load, and were more insulin resistant. Compared with those patients with normal glucose tolerance, the IGT patients were older, had a later age of onset, higher waist or hip circumference and body mass index, higher levels of low-density lipoprotein and triglycerides and higher insulin resistance. Furthermore, IGT patients had higher PANSS total and negative symptom subscale scores, but no greater cognitive impairment except on the emotional intelligence index of the MCCB.
IGT occurs with greater frequency in FEDN schizophrenia, and shows association with demographic and anthropometric parameters, as well as with clinical symptoms but minimally with cognitive impairment during the early course of the disorder.
Comparative study of CO2 laser-produced tin-droplet plasma with and without pre-pulse laser has been presented. A pre-pulse laser and the CO2 laser was combined and focused to tin-droplet with a diameter of 180 µm. The emitted Sn ions were detected by several Faraday cups to obtain angular distribution of ions in the laser-produced tin-droplet plasma. The influence of pre-pulse laser energy and delay time between pumping laser and pre-pulse laser on the ion characteristics was investigated. It is illustrated that ion average kinetic energy from CO2 laser-produced plasma (LPP) can be reduced when the tin-droplet target has been replaced by the preformed Sn plasma. The obtained optimal delay time with the lowest ion average kinetic energy is about hundreds of nanoseconds. The ion time-of-flight spectra show a twin peak structure in laser-irradiating preformed Sn plasma. And a superimposed Maxwell–Boltzmann (MB) distribution is proposed to describe this twin peak ion time-of-flight spectra. The fitting results quite agree with the raw ion time-of-flight spectra in current experiment. Then, the fitted plasma temperatures and mass-center velocities with various delay times in laser-irradiating preformed plasma are obtained, and the fitted plasma temperatures can be comparable with ion average kinetic energy in double-pulse LPP, which justified the rationality using this superimposed MB distribution.
Accelerator mass spectrometry (AMS) radiocarbon dating a continuous core from Lake Gun Nur, northern Mongolia, shows a period between 10 and 8 ka BP that could not be dated accurately. Further dating on alkali-insoluble residue and humic acid from the same samples in the Gun Nur core suggest that this AMS 14C date anomaly is neither analytical nor material related. We hypothesize that the 14C anomaly may be derived from increasing production rates of 14C caused by diminished solar activity, a low 14CO2/14CO ratio in the atmosphere, or an unstable 14C flux in the lower atmosphere caused by changing geomagnetic field strength. Our results imply that the 14C data used for 14C age calibration cannot correct the age-depth regression between 8 and 10 ka BP to fit the age-depth model along with other time intervals.
Mitochondria plays an important role in the regulation of energy homeostasis. Moreover, mitochondrial biogenesis accompanies skeletal myogenesis, and we previously reported that maternal high-energy diet repressed skeletal myogenesis in pig fetuses. Therefore, the aim of this study was to evaluate the effects of moderately increased maternal energy intake on skeletal muscle mitochondrial biogenesis and function of the pig fetuses. Primiparous purebred Large White sows were allocated to a normal energy intake group (NE) as recommended by the National Research Council (NRC) and a high energy intake group (HE, 110% of NRC recommendations). On day 90 of gestation, fetal umbilical vein blood and longissimus (LM) muscle were collected. Results showed that the weight gain of sows fed HE diet was higher than NE sows on day 90 of gestation (P<0.05). Maternal HE diet increased fetal umbilical vein serum triglyceride and insulin concentrations (P<0.05), and tended to increase the homeostasis model assessment index (P=0.08). Furthermore, HE fetuses exhibited increased malondialdehyde concentration (P<0.05), and decreased activities of antioxidative enzymes (P<0.05) and intracellular NAD+ level (P<0.05) in LM muscle. These alterations in metabolic traits of HE fetuses were accompanied by reduced mitochondrial DNA amount (P<0.05) and down-regulated messenger RNA expression levels of genes responsible for mitochondrial biogenesis and function (P<0.05). Our results suggest that moderately increased energy supply during gestation decreases mitochondrial biogenesis, function and antioxidative capacity in skeletal muscle of pig fetuses.
It remains unclear whether the topological deficits of the white matter network documented in cross-sectional studies of chronic schizophrenia patients are due to chronic illness or to other factors such as antipsychotic treatment effects. To answer this question, we evaluated the white matter network in medication-naive first-episode schizophrenia patients (FESP) before and after a course of treatment.
We performed a longitudinal diffusion tensor imaging study in 42 drug-naive FESP at baseline and then after 8 weeks of risperidone monotherapy, and compared them with 38 healthy volunteers. Graph theory was utilized to calculate the topological characteristics of brain anatomical network. Patients’ clinical state was evaluated using the Positive and Negative Syndrome Scale (PANSS) before and after treatment.
Pretreatment, patients had relatively intact overall topological organizations, and deficient nodal topological properties primarily in prefrontal gyrus and limbic system components such as the bilateral anterior and posterior cingulate. Treatment with risperidone normalized topological parameters in the limbic system, and the enhancement positively correlated with the reduction in PANSS-positive symptoms. Prefrontal topological impairments persisted following treatment and negative symptoms did not improve.
During the early phase of antipsychotic medication treatment there are region-specific alterations in white matter topological measures. Limbic white matter topological dysfunction improves with positive symptom reduction. Prefrontal deficits and negative symptoms are unresponsive to medication intervention, and prefrontal deficits are potential trait biomarkers and targets for negative symptom treatment development.