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In her position article, Lee (2019) compellingly argues for focused written corrective feedback (FWCF) and offers clear guidelines for teachers to shift their feedback approach. As English language teaching practitioners in Chinese universities, we share Lee's view against any unthinking adherence to comprehensive written corrective feedback (CWCF) and advocate principled feedback practice. Our response begins by presenting the common ground between Lee's and our stance, followed by problematizing her ‘less-is-more’ argument. Finally, following Lee's guidelines, we propose a few context-specific suggestions to help university teachers in mainland China and other contexts better implement FWCF.
Previous nutritional studies have shown that insulin regulation is different between DT and A strains of gibel carp. As leptin plays a pivotal role in the effects of insulin, we hypothesized that leptin regulation of glucose and lipid metabolism would differ between the two strains. To test our hypothesis, recombinant human leptin was injected into two strains. The results showed that leptin activated PI3K-AKT, AMPK-ACC, and JAK2-STAT signaling pathways in both strains. Hypoglycemia induced by leptin might be due to higher glucose uptake by the liver and muscles together with enhanced glycolytic potential and reduced gluconeogenic potential. Decreased lipogenesis and up-regulated fatty acid oxidation were induced by leptin. In terms of genotype, the PI3K-AKT signaling pathway was more strongly activated by leptin in the muscle tissue of the A strain, as reflected by the heightened phosphorylation of AKT. Furthermore, glycogen content, glycolytic enzyme activity, and gluconeogenic capability were higher in the A strain than the DT strain. Strain A had higher levels of fatty acid synthesis and lipolytic capacity in the liver than the DT strain, but the opposite was true in white muscle. Regarding leptin-genotype interactions, the DT strain displayed stronger regulation of glucose metabolism in the liver by leptin as compared to the A strain. Moreover, a more active JAK2-STAT signaling pathway accompanied by enhanced inhibition of fatty acid synthesis by leptin was observed in the DT strain. Overall, the regulation of glucose and lipid metabolism by leptin differed between the two strains, as expected.
The dynamical stability of the cable-driven lower-limb rehabilitation training robot (CLLRTR) is a crucial question. Based on the established dynamics model of CLLRTR, the solution to the wrench closure of the under-constrained system is presented. Secondly, the stability index of CLLRTR is proposed by the Krasovski method. Finally, in order to analyze the stability distribution of CLLRTR in the workspace, the stability evaluation index in the workspace is calculated using the eigenvalue decomposition method. The stability distribution laws of CLLRTR are further verified by the experimental study. The results provide references for studying trajectory planning and anti-pendulum control of CLLRTR.
The 7 degrees of freedom (DOF) redundant manipulator greatly improves obstacle/singularity avoidance capability and operational flexibility. However, the inverse kinematics problem of this manipulator is very difficult to solve because it has an infinite number of solutions. This paper uses a new numerical sequence processing method with a closed-loop framework to solve the inverse kinematics of the 7-DOF redundant manipulator. Simulation and experiment show that this method has high commonality. No special structure of the robot is required, and this method has improved computational efficiency and reliability.
Since the outbreak of 2019 novel coronavirus infection (2019-nCoV) in Wuhan City, China, pediatric cases have gradually increase. It is very important to prevent cross-infection in pediatric fever clinics, how identify children with fever in pediatric fever clinics, and strengthen the management of pediatric fever clinics. According to prevention and control programs, we propose the guidance on the management of pediatric fever clinics during the novel coronavirus pneumonia epidemic period, which outlines in detail optimizes processes, prevents cross-infection, health protection and disinfection of medical staff. The present consideration statement summarizes current strategies on pre-diagnosis, triage, diagnosis, treatment, and prevention of 2019-nCoV infection, which provide practical suggestions on strengthening the management of pediatric fever clinics during the novel coronavirus pneumonia epidemic period.
The Antarctic subglacial drilling rig (ASDR) is designed to recover 105 mm-diameter ice cores up to 1400 m depth and 41.5 mm-diameter bedrock cores up to 2 m in length. In order to ensure safe and convenient drilling, drilling auxiliaries are designed to support fieldwork and servicing. These auxiliaries are subdivided into several systems for power supply, drill tripping in the borehole, ice core and chip processing, and drill servicing and maintenance. The required equipment also includes two generators, a drilling winch with a cable, logging winch with a cable, control desk, pipe handler with a fixed clamp, chip chamber vibrator, centrifuge, emergency devices and fitting and electrical tools. Additionally, several environmental protective measures such as a new liquid-tight casing with a thermal casing shoe and a bailing device for recovering drilling fluid from the borehole were designed. Most of the auxiliaries were tested during the summer of 2018–2019 near Zhongshan Station, East Antarctica while drilling to the bedrock to a depth of 198 m.
The clinical characteristics of patients with COVID-19 were analysed to determine the factors influencing the prognosis and virus shedding time to facilitate early detection of disease progression. Logistic regression analysis was used to explore the relationships among prognosis, clinical characteristics and laboratory indexes. The predictive value of this model was assessed with receiver operating characteristic curve analysis, calibration and internal validation. The viral shedding duration was calculated using the Kaplan–Meier method, and the prognostic factors were analysed by univariate log-rank analysis and the Cox proportional hazards model. A retrospective study was carried out with patients with COVID-19 in Tianjin, China. A total of 185 patients were included, 27 (14.59%) of whom were severely ill at the time of discharge and three (1.6%) of whom died. Our findings demonstrate that patients with an advanced age, diabetes, a low PaO2/FiO2 value and delayed treatment should be carefully monitored for disease progression to reduce the incidence of severe disease. Hypoproteinaemia and the fever duration warrant special attention. Timely interventions in symptomatic patients and a time from symptom onset to treatment <4 days can shorten the duration of viral shedding.
A new, modified version of the cable-suspended Ice and Bedrock Electromechanical Drill (IBED) was designed for drilling in firn, ice, debris-rich ice and rock. The upper part of the drill is almost the same for all drill variants and comprises four sections: cable termination, a slip-ring section, an antitorque system and an electronic pressure chamber. The lower part of the IBED comprises an auger core barrel, reamers, a core barrel for ice/debris-ice drilling and a conventional geological single-tube core barrel or custom-made double-tube core barrel. First, the short and full-scale field versions of the IBED were tested at an outdoor testing stand and a testing facility with a 12.5 m-deep ice well. Then, in the 2018–2019 summer season, the IBED was tested in the field at a site ~12 km south of Zhongshan Station, East Antarctica, and a ~6 cm bedrock core was recovered from a 198 m-deep borehole. A total of 18 d was required to penetrate the ice sheet. The retrieved core samples of blue ice, basal ice and bedrock provided valuable information regarding the Earth's paleo-environment.
The surface topology of biomaterial has a definite effect on the growth behavior of nerve cells for peripheral nerve regeneration. In this study, the silk fibroin (SF) film with different anisotropic microgroove/ridge was constructed by micropatterning technology. The effects of topologies width on the directional growth of dorsal root ganglion (DRG) neurons were evaluated. The results showed that the topological structure of the SF film with higher SF concentration was more clear and complete. The microtopography of the SF film with a concentration of 15% and a groove width of around 30 μm could effectively guide the directional growth of the nerve fibers of DRG. And nerve fibers could obviously form nerve fiber bundles which may have a certain pavement effect on the recovery of nerve function. The study indicated that the SF film with a specific width of the topological structure may have potential applications in the field of directional nerve regeneration.
Already home to 23% of the global elderly population, China will experience further demographic change in the coming decades. To address the consequences of population ageing, the Chinese government is implementing major social insurance reforms and promotes the development of private insurance markets. We aim to inform these initiatives by developing a new method to project healthy life expectancy (HLE) in different regions. HLE is an important population health measure which is increasingly used in the actuarial literature. Our new approach relies on publicly available data from the Global Burden of Disease Study for life expectancy and HLE for 139 countries. We use the model to estimate HLE at birth in 2015 for 31 province-level regions in China for both males and females. We discuss the implications of our results for planned increases in the retirement age in China and for long-term care insurance pricing.
The cotton-wheat double-cropping system is widely used in the Yellow River Valley of China, but whether and how different planting patterns within cotton-wheat double-cropping systems impact heat and light use efficiency have not been well documented. A field experiment investigated the effects of the cropping system on crop productivity and the capture and use efficiency of heat and light in two fields differing in soil fertility. Three planting patterns, namely cotton intercropped with wheat (CIW), cotton directly seeded after wheat (CDW), and cotton transplanted after wheat (CTW), as well as one cotton monoculture (CM) system were used. Cotton-wheat double cropping significantly increased crop productivity and land equivalent ratios relative to the CM system in both fields. As a result of increased growing degree days (GDD), intercepted photosynthetically active radiation (IPAR), and photothermal product (PTP), the capture of light and heat in the double-cropping systems was compared with that in the CM system in both fields. With improved resource capture, the double-cropping systems exhibited a higher light and heat use efficiency according to thermal product efficiency, solar energy use efficiency (Eu), radiation use efficiency (RUE), and PTP use efficiency (PTPU). The cotton lint yield and biomass were not significantly correlated with RUE across cropping patterns, indicating that RUE does not limit cotton production. Among the double-cropping treatments, CDW had the lowest GDD, IPAR, and PTP values but the highest heat and light resource use efficiency and highest overall resource use efficiency. This good performance was even more obvious in the high-fertility field. Therefore, we encourage the expanded use of CDW in the Yellow River Valley, especially in fields with high fertility, given the high productivity and resource use efficiency of this system. Moreover, the use of agronomic practices involving a reasonably close planting density, optimized irrigation and nutrient supply, and the application of new short-season varieties of cotton or wheat can potentially enhance CDW crop yields and productivity.
A critical region of PTSD is the medial prefrontal cortex, which may be impaired in this disorder. Neuroimaging studies have reported reduced cortical volumes and neuronal integrity, as well as decreased function in medial prefrontal structures in this disorder.
The aim of this study is to find whether mPFC neurons have cell apoptosis, which may lead to the dysfunction of mPFC of PTSD.
The group to test apotosis was divided into SPS after1d, 4d, 7d, 14d and control group. Expression of caspase-9 and caspase-3 were detected by immunohistochemistry, immunofluorescence, western blotting and RT-PCR.
Caspase-3 was located in cytoplasm. Evaluation of Caspase-3 immunohistochemistry showed a significant increased in the SPS-1d, SPS-4d and SPS-7d compared with the normal control group, then gradually decreased in SPS-14d. Caspase-9-positive cells were expressed in the control group and the SPS groups, The positive expression was green fluorescence, which in cell body, membrane, and processes. The mRNA levels of Caspase-9 in the SPS rats were significant increased on days 1d and 4d then gradually decreased. The Caspase-3 mRNA levels peaked at SPS-7d, then decreased on SPS-14d.
The mPFC neuronal apoptosis through mintochodrial pathway would play an important role in the dysfunction of mPFC in post traumatic stress disorder patients.
The aim of this study was to reveal the possible mechanisms involved in apoptosis induced by single prolonged stress (SPS) in hippocampus of post-traumatic stress disorder (PTSD) rats.
SPS is one of the animal models proposed for PTSD. Wistar rats were killed at 1, 4, 7, 14 and 28days after exposure to SPS. Expression of caspase-9, caspase-3, cytochrome c, Bcl-2 and Bax was detected by immunohistochemistry, immunofluorescence, western blotting and electron microscopy. Apoptotic cells were assessed by TUNEL method.
Our results showed apoptotic cells were significantly increased in hippocampus of SPS rats, accompanied by release of cytochrome c from the mitochondria into the cytosol, increase of caspase-9 and caspase-3 expression and decrease of the Bcl-2 / Bax ratio.
The results indicate that SPS induced apoptosis in hippocampus of PTSD rats, and the mitochondrial pathway was involved in the process of SPS induced apoptosis. *National Natural Science Foundation of China
Post-traumatic stress disorder (PTSD) is a significant problem,The medial prefrontal cortex (mPFC) is known to be significantly involved in emotional adjustment.
To discuss the issue of post-traumatic stress disorder (PTSD) rat apoptosis-related genes Bcl-2, Bax and medial prefrontal cortex (mPFC) neuronal apoptosis, and to provide experimental evidence to reveal PTSD pathogenesis.
The single-prolonged stress(SPS) method was used to set up the rat PTSD models There were five groups after SPS 1 day 4 days 7 days 14 days groups and control group Serum corticosterone level was determined with chemiluminescence, mPFC neuronal apoptosis changes and detection of apoptotic index were detected with transmission electron microscopy, hoechst 33342 staining and in situ nick end labeling method (TUNEL) staining. Immunohistochemistry, immunofluorescence, RT-PCR and western blotting were used to detect the expressions of Bcl-2 and Bax in the medial prefrontal cortex neuronal.
PTSD rat mPFC neuron cell apoptosis, the number of apoptotic cells gradually increased with time and reached a peak at 7 days after SPS stimulates. Bcl-2 expression reached a peak at 4d and Bax expression reached a peak at 7d after SPS stimulates, Bcl-2/Bax ratio transient increased and then gradually decreased, reached a lowest point in seventh days after SPS stimulates.
The expression of apoptosis related genes Bcl-2 and Bax increase and their ratio imbalances are likely to be one of the reasons that lead to PTSD in rat mPFC neurons apoptosis, which may provide the pathophysiology basis for PTSD.
To investigate the difference of visual pattern memory among first-episode treatment-naive patients with deficit and nondeficit schizophrenia.
199 first-episode treatment-naive patients with schizophrenia, and 148 controls were recruited. Schedule for the Deficit Syndrome (SDS) was used to categorize the patients into deficit or nondeficit subtype. Pattern Recognition Memory (PRM) was used to test the immediate and delayed mode of visual pattern memory. Positive and Negative Symptom Scale PANSS was used to assess the degree of patients symptoms.
The PRM immediate mode and delayed mode percent correct was significant lower and time latency was significant longer in two subtypes of patients. There were no significant difference in the performance of immediate mode of PRM between deficit and nondeficit patients[(86.49 ± 15.34) vs. (87.28 ± 16.00), P=0.960]. But the impairment was more severe in patients with deficit schizophrenia [percent correct (63.10 ± 19.17) vs. (70.69 ± 15.34), P< 0.001 time latency 5086.80 ± 7528.54 vs. 3527.40 ± 3649.08 P=0.024] in the delayed mode. and PRM has no significant correlation with the negative symptoms of deficit schizophrenia.
There were significant difference in the performance of immediate and delayed mode of PRM between patients and controls. The difference between first-episode treatment-naïve deficit schizophrenia and nondeficit schizophrenia was only in delayed mode of PRM, and has no correlation with the primary negative symptoms. The deficit schizophrenia is a subtype of schizophrenia with unique impairment of cognitive functions.
To evaluate the upper airway morphology changes associated with ageing in adult Chinese patients with obstructive sleep apnoea.
A total of 124 male patients diagnosed with obstructive sleep apnoea by overnight polysomnography, who underwent upper airway computed tomography, were enrolled. The linear dimensions, cross-sectional area and volume of the upper airway region and the surrounding bony frame were measured. The association between ageing and upper airway morphology was analysed.
Soft palate length, minimum cross-sectional area of the retroglossal region, lateral dimensions at the minimum cross-sectional area of the retropalatal and retroglossal regions, nasopharyngeal volume, and average cross-sectional area of the nasopharyngeal region were found to significantly increase with ageing in all patients, while the upper airway shape flattened with ageing. The volume of the retropalatal region increased with ageing among the patients with a body mass index of less than 24 kg/m2. The volume of parapharyngeal fat pad increased with ageing among patients with a body mass index greater than 28 kg/m2.
A number of dimensional, cross-sectional and volumetric parameters of the pharynx increased with age, indicating that non-anatomical factors may play a more important role in the pathogenesis of obstructive sleep apnoea in aged patients.