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Xiao-Ling Zou,1,* Jin-Jie Wu,2,* Hui-Xia Ye,3,* Ding-Yun Feng,1,* Ping Meng,1 Hai-Ling Yang,1 Wen-Bin Wu,1 Hong-Tao Li,1 Zhen He,2 Tian-Tuo Zhang1 1Department of Pulmonary and Critical Care Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Institute of Respiratory Diseases of Sun Yat-sen University, Guangzhou, People’s Republic of China; 2Department of Colorectal Surgery, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China; 3Department of Gynecology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, People’s Republic of China*These authors contributed equally to this workCorrespondence: Tian-Tuo ZhangDepartment of Pulmonary and Critical Care Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Institute of Respiratory Diseases of Sun Yat-sen University, 600 Tianhe Road, Guangzhou, 510630, People’s Republic of ChinaEmail zhtituli@163.comZhen HeDepartment of Colorectal Surgery, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510655, Guangdong, People’s Republic of ChinaEmail hezh5@mail.sysu.edu.cnObjective: This study aimed to investigate the gut microbiome profile in different inflammatory phenotypes of treatment-naive newly diagnosed asthmatic adults, to gain insight on the associations between intestinal microbiota and phenotypic features that characterize asthma heterogeneity to develop new treatments for asthma.Methods: Fresh stool samples were obtained from 20 healthy subjects and 47 newly diagnosed asthmatic patients prior to any interventions. The asthmatics were divided into allergic and non-allergic cohorts. Intestinal microbiota was analyzed by 16S rRNA next-generation sequencing. Demographic and clinical parameters were collected. Alpha and beta diversity analysis were calculated to detect differences within sample phylotype richness and evenness between controls and asthmatic patients. Statistically significant differences between samples were analyzed for all used metrics, and features of gut bacterial community structure were evaluated in relation to extensive clinical characteristics of asthmatic patients.Results: Gut microbial compositions were significantly different between asthmatic and healthy groups. Alpha-diversity of the gut microbiome was significantly lower in asthmatics than in controls. The microbiome between allergic and non-allergic asthmatic patients were also different, and 28 differential species were identified. PPAR signaling pathway, carotenoid biosynthesis, and flavonoid biosynthesis were significantly positively correlated with allergy-associated clinical index, including FENO value, blood eosinophil counts, and serum IgE and IL-4 levels. A combination of Ruminococcus bromii, Brevundimonas vesicularis, and Clostridium disporicum showed an AUC of 0.743 in the specific allergic/non-allergic cohort. When integrating C. disporicum, flavone, flavonol biosynthesis, and serum IL-4 values, the AUC achieved 0.929 to classify asthmatics. At the same time, C. colinum and its associated functional pathway exhibited an AUC of 0.78 to distinguish allergic asthmatics from those without allergies.Conclusion: We demonstrated a distinct taxonomic composition of gut microbiota in different asthmatic phenotypes, highlighting their significant relationships. Our study may support considerations of intestinal microbial signatures in delineating asthma phenotypes.Keywords: asthma, phenotypes, gut microbiota, 16S rRNA next-generation sequencing, functional pathway

Novel coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing public-health pandemic worldwide. Although SARS-CoV-2 has been known to spread primarily through respiratory droplets, recent evidence also supports fecal/oral as an additional route of transmission, raising concerns over gastrointestinal (GI) transmission of the infection. Herein, we, as the front-line Chinese GI surgeons, would like to share our experience and lessons in the combat against COVID-19. It is essential to create science-based, rational, and practical strategies during the outbreak of COVID-19. Here, we provide multi-institutional consensus on minimizing disease transmission while continuing to provide care from all aspects for patients in GI surgery, including outpatient clinics, inpatient units, gastrointestinal endoscopy centers, and adjustments in perioperative care. Our experiences and recommendations are worth sharing and may help to establish specific infection-control and outcome measures.

During current research, the effects of deoxynivalenol (DON) exposure on cerebral lipid peroxidation, neurotransmitter secretion and calcium homeostasis in chicks were evaluated. One hundred and twenty Hailan chicks (male, 1-day-old) were randomly divided into four groups. Chicks in low, medium and high dose groups were fed with 0.27, 1.68 and 12.21 mg/kg−1 DON respectively by gavage according to feed intake. Chicks in control group were fed with physiological saline by gavage. The trials were conducted for 36 d. At the end of the trials, twenty chicks per group were sacrificed, and the cerebra were collected for measuring the brain indices. Compared with the control group, the activities of total superoxide dismutase (T-SOD) and glutathione peroxidase were significantly decreased in treatment groups (P

Strictures are common complications after ileal pouch surgery. The aim of this study is to evaluate the efficacy and safety of endoscopic stricturotomy vs. endoscopic balloon dilation (EBD) in the treatment of pouch inlet strictures. All consecutive ulcerative colitis patients with the diagnosis of pouch inlet or afferent limb strictures treated in our Interventional Inflammatory Bowel Disease Unit (i-IBD) from 2008 to 2017 were extracted. The primary outcomes were surgery-free survival and post-procedural complications. A total of 200 eligible patients were included in this study, with 40 (20.0%) patients treated with endoscopic stricturotomy and 160 (80.0%) patients treated with EBD. Symptom improvement was recorded in 11 (42.3%) patients treated with endoscopic stricturotomy and 16 (13.2%) treated with EBD. Subsequent surgery rate was comparable between the two groups (9 [22.5%] vs. 33 [20.6%], P = 0.80) during a median follow-up of 0.6 years (interquartile range [IQR] 0.4–0.8) vs. 3.6 years (IQR 1.1–6.2) in patients receiving endoscopic stricturotomy and EBD, respectively. The overall surgery-free survival seems to be comparable as well (P = 0.12). None of the patients in the stricturotomy group developed pouch failure, while 9 patients (5.6%) had pouch failure in the balloon dilation group (P = 0.17). Procedural bleeding was seen in three occasions (4.7% per procedure) in patients receiving endoscopic stricturotomy and perforation was seen in three occasions (0.8% per procedure) in patients receiving EBD (P = 0.02). In multivariable analysis, an increased length of the stricture (hazard ratio [HR] 1.4, 95% confidence interval [CI] 1.0–1.8) and concurrent pouchitis (HR 2.5, 95% CI 1.0–5.7) were found to be risk factors for the requirement of surgery. Endoscopic stricturotomy and EBD were both effective in treating patients with pouch inlet or afferent limb strictures, EBD had a higher perforation risk while endoscopic stricturotomy had a higher bleeding risk.

Single photon counting using a charge-coupled device (CCD) is a conventional method of measuring the x-ray production of laser plasma. But the spectrum is seriously distorted when measuring a short pulse laser plasma x-ray source. Here we explore this abnormal spectral distortion using a silicon sensor-based CCD (PIXIS-XB: 1300R). We found that the spectral distortion is caused by the continuous spectrum of Compton scattering electrons and the K-α and K-β characteristic lines of Ag elements excited by the harder x-rays of >25 keV. We calibrated the detection efficiency of the incident x-ray, the excitation efficiency of the Ag characteristic lines and the Compton scattering electrons spectrum in the x-ray energy range from 20 keV to 100 keV. We also improve the algorithm of spectrum reconstruction to loosen the exposure level limit markedly. Our effort extends the detecting range of silicon sensor-based CCDs from 0.5–30 keV to 0.5–80 keV. The present analysis can also be used in the spectral extraction of GaAs and CdTe high-Z sensor-based CCDs.

Based on the mission requirements of agile satellite, the control method of large angle maneuver was investigated in this paper. The single gimbal control moment gyroscope (sgcmg) of pyramid configuration is taken as the executor of the satellite. In order to avoid the singularity of sgcmgs, robust pseudo-inverse steering logic is used. An attitude active disturbance rejection controller (adrc) was designed. The expected attitude maneuver information that got by gauss pseudo-spectral method (gpm) took the place of that got by tracking differentiator (td). The constraints of satellite and sgcmgs are considered. Dynamics decoupling and disturbance observation of satellite were realized by using nonlinear extended state observer (neso). Then based on neso, nonlinear error feedback controller (nlsef) effectively suppresses the disturbance. The simulation results show that the attitude active disturbance rejection controller has steady control performance and can reject the disturbance better.

With new generation neutron sources, traditional neutron detectors cannot satisfy the demands of the applications, especially under high flux. Furthermore, facing the global crisis in He-3 gas supply, research on new types of neutron detector as an alternative to He-3 is a research hotspot in the field of particle detection. GEM (Gaseous Electron Multiplier) neutron detectors have high counting rate, good spatial and time resolution, and could be one future direction of the development of neutron detectors. In this paper, the physical process of neutron detection is simulated with Geant4 code, studying the relations between thermal conversion efficiency, boron thickness and number of boron layers. Due to the special characteristics of neutron detection, we have developed a novel type of special ceramic nTHGEM (neutron THick GEM) for neutron detection. The performance of the nTHGEM working in different Ar/CO2 mixtures is presented, including measurements of the gain and the count rate plateau using a copper target X-ray source. A detector with a single nTHGEM has been tested for 2-D imaging using a Cf-252 neutron source. The key parameters of the performance of the nTHGEM detector have been obtained, providing necessary experimental data as a reference for further research on this detector.

A bistable liquid crystal cell with splay and π twist stable states is obtained by doping a chiral additive in a splay cell filled with dual frequency liquid crystals. The switching between the two states is achieved by using a sequential waveform of low and high frequencies. The switching mechanisms are proposed by using the backflow effect together with the anisotropic properties of dual frequency liquid crystals. As a result, the two stable states have the superior memory characteristics due to the topological inequivalence.