Defects, band bending and ionization rings in MoS2

Chalcogen vacancies in transition metal dichalcogenides are widely acknowledged as both donor dopants and as a source of disorder. The electronic structure of sulphur vacancies in MoS₂however is still controversial, with discrepancies in the literature pertaining to the origin of the in-gap features observed via scanning tunneling spectroscopy (STS) on single sulphur vacancies. Here we use a combination of scanning tunnelling microscopy and STS to study embedded sulphur vacancies in bulk MoS₂crystals. We observe spectroscopic features dispersing in real space and in energy, which we interpret as tip position- and bias-dependent ionization of the sulphur vacancy donor due to tip induced band bending. The observations indicate that care must be taken in interpreting defect spectra as reflecting in-gap density of states, and may explain discrepancies in the literature.

[Efficacy and safety of endothelin receptor antagonists combined with phosphodiesterase 5 inhibitor in the treatment of pulmonary arterial hypertension: a network meta-analysis]

Objective: To examine the efficacy and safety of endothelin receptor antagonists (ERA) combined with phosphodiesterase 5 inhibitors (PDE5i) in the treatment of pulmonary artery hypertension (PAH). Methods: Computer-based retrieval was performed on PubMed, Cochrane Library, CNKI, Wanfang, and VIP database (up to February 12th, 2021). Randomized controlled trials about endothelin receptor antagonists (ERAs) or PDE5i in patients with PAH were collected. The change of 6-minute walking distance (6MWD) in 12-16 weeks was used as primary outcome index. Case fatality rate, worsening clinical events, WHO functional class (FC) improvement, adverse events (AEs), serious adverse events (SAE) were the key secondary outcomes indicators. STATA 16.0 software was used for network meta-analysis, and the pooled estimates of odds ratios (ORs) or weighted mean differences (WMDs) and 95% confidence intervals (CIs) of the results were shown. To help explain ORs and WMDs, we used the surface under the cumulative ranking curve (SUCRA) to calculate the probability of each intervention. Results: We included 29 trials with 5 949 participants. In network meta-analysis, Bosentan combined with Sildenafil (WMD=53.93, 95%CI=6.19-101.66) had shown the greatest improvement in 6MWD compared with placebo, followed by Bosentan combined with Tadalafil (WMD=50.84, 95%CI=7.05-94.62), Ambrisentan combined with Tadalafil (WMD=46.67, 95%CI=15.88-77.45), Bosentan (WMD=29.44, 95%CI=5.86-53.02), Ambrisentan (WMD=23.90, 95%CI=0.31-47.48) and Macitentan (WMD=21.57, 95%CI=2.45-40.69). According to SUCRA, the effects of different intervention measures on improving 6MWD in patients with arterial pulmonary hypertension were as follows: Bosentan+Sildenafil (82.9%)>Bosentan+Tadalafil (78.4%)>Ambrisentan+Tadalafil (77.1%)>Bosentan (49.2%)>Sildenafil (48.5%)>Ambrisentan (40.3%)>Macitentan (37.3%)>Tadalafil (33.0%)>Placebo (3.3%). For the WHO functional class, Sildenafil (OR=2.90, 95%CI=1.04-8.08) was optimal compared with placebo, followed by Bosentan (OR=2.15, 95%CI=1.15-4.04), and there was no significant difference in the rest. For clinical worsening, Bosentan combined with Tadalafil (OR=0.08, 95%CI=0.01-0.49) performed best compared with placebo, followed by Bosentan (OR=0.20, 95%CI=0.11-0.38), Bosentan combined with Sildenafil (OR=0.21, 95%CI=0.09-0.46), Ambrisentan combined with Tadalafil (OR=0.27, 95%CI=0.15-0.50), Sildenafil (OR=0.33, 95%CI=0.17-0.66) and Tadalafil (OR=0.44, 95%CI=0.21-0.90). There was no statistical difference between all interventions and placebo in terms of the incidence of adverse events and serious adverse events. For case fatality rate, Ambrisentan (OR=0.28, 95%CI=0.11-0.74) was statistically superior to placebo and there was no statistics difference in the rest. Conclusions: The combination therapy of ERAs and PDE5i performed well in the short-term improvement of motor function. Furthermore, there was no significant difference with monotherapy in terms of safety. However, it is worth emphasizing that the choice of treatment should be based on the patient's individualized situation and the patient's requirements.

[The westward migration of Tongji Medical College during the Anti-Japanese War]

Tongji Medical College began its "education Long March" after the Battle of Shanghai in 1937, with six westward migrations across almost 10,000 kilometers over eight years. It first moved to the city of Shanghai because Tongji Medical College had to rent space in Shanghai, then moved to Jinhua in Zhejiang Province soon afterwards. After that it migrated to Ganzhou and Jian in Jiangxi Province, then He County in Guangxi Province and Kunming in Yunnan Province, ultimately locating in Li Village in Sichuan Province. Tongji Medical College was operated by Chinese and implemented high-level administration and teaching under the difficult conditions during the Anti-Japanese War. As a result, Tongji Medical College made advances in the medical field, such those by Professor Wu Mengchao. It also made advancements in research and treatment, such as identifying pathogenesis of a local epidemic and offering some treatment methods, and popularised medical knowledge for local people by exhibitions and news paper columns. It also established the Number One and the Number Five UMC Trauma Centre, participating in battlefield treatment. The German teachers of Tongji Medical College, who did not move to the west, established a German Medical School in Shanghai. Tongji Medical College returned back to Shanghai, incorporating the German Medical School in Shanghai after the Anti-Japanese War.

[Research advances on the promotive healing effect of hydrogel dressing for diabetic foot wound]

In recent years, the number of diabetic patients has gradually increased, and the number of patients with diabetic foot has also increased. Diabetic foot has a high rate of disability and death, seriously affects the patients' quality of life, shortens life expectancy, and brings heavy social burden. The current treatment methods for diabetic foot are insufficient. The concepts and methods of tissue engineering provide new thoughts and means for the treatment of diabetic foot. This article introduces the pathogenesis of diabetic foot wounds, the factors leading to non-healing of diabetic foot, the applications of functional hydrogel dressings in the treatment of diabetic foot and their technical methods of functional hydrogel dressings for treating skin wounds in diabetic animals, and the future development direction of functional hydrogel dressing for treating diabetic foot wounds is prospected.

[Epidemiology of chronic cough in China: current status and future perspective]

Chronic cough is one of the most common major complaints in medical outpatient. Chronic cough not only seriously affects quality of personal life, but also burdens public health. Large-scale and high-quality epidemiological study on chronic cough has not been carried out in China, and relevant reviews are also lacking. Therefore, based on the studies concerning epidemiology of chronic cough in China, we reviewed the prevalence, risk factors, etiology, quality of life and economic burden. In addition, future perspectives and reasonable suggestions for the development of epidemiology of chronic cough were also proposed.

[Comparison of early outcome between one-stage hybrid technique and frozen elephant thunk technique in the treatment of Stanford A aortic dissection involving the arch]

Objective: To analyze the early outcome of one-stage hybrid technique in the treatment of Stanford type-A aortic dissection involving the arch and compare its therapeutic efficacy with the classical frozen elephant trunk technique (FET). Methods: A total of 106 patients with Stanford type-A aortic dissection involving the arch in Department of Cardiac and Vascular Surgery, 1st Affiliated Hospital of Soochow University from October 2015 to October 2019 was collected. All patients in this group were treated with one-stage hybrid technique (modified arch debranching technique) without deep hypothermia circulation. Meanwhile, 30 patients with Stanford type A dissection involving the arch who underwent FET from January 2014 to September 2015 were collected. The therapeutic effects of the two surgical methods were analyzed and compared. Results: The age [M (Q₁, Q₃)] of 106 patients in hybrid group was 49.0 (40.0, 55.0) years, including 89 males and 17 females. The age [M(Q₁, Q₃)] of 30 patients in FET group was 49.5 (41.5, 65.3) years, including 24 males and 6 females. The time [M(Q₁, Q₃)] of using ventilator in hybrid group was 56.0 (38.0, 72.0) h, which was shorter than 127.0 (92.0, 145.0) h in FET group (P<0.001). The incidence of cerebral infarction in hybrid group was 2.8% (3 cases), which was lower than 13.3% (4 cases) in FET group (P=0.042); the incidence of postoperative renal insufficiency in hybrid group was 7.5% (8 cases), which was lower than 23.3% (7 cases) in FET group (P=0.023); the ICU time [M (Q₁, Q₃)] in hybrid group was 8.0 (6.0, 10.0) d, which was shorter than 14.0 (8.3, 24.0) d in FET group (P<0.001). Conclusion: Compared with FET, one-stage hybrid technology is safer and more effective in the treatment of Stanford type A aortic dissection involving the arch. Its short-term therapeutic efficacy appears good.

[Recent HIV infection and associated factors among men who have sex with men in Jiangsu province]

Objective: To understand the incidence of HIV infections and associated factors among men who have sex with men (MSM) in Jiangsu province. Methods: Based on national AIDS sentinel surveillance in 2019, MSM from 13 cities in Jiangsu were recruited for questionnaire interview and laboratory testing during April to July, 2019. Seropositive samples were tested with Limiting-antigen avidity enzyme immunoassay to detect recent HIV infections. The incidence of HIV infection in MSM were calculated according to the formula and parameters from China CDC. Multivariable logistic regression analysis was used to identify factors associated with recent infection of HIV. Results: A total of 4 469 MSM were subjects and the incidence of HIV infection were 4.5% (95%CI: 3.4%-5.5%).Multivariate logistic regression analysis results showed that compared with these aged ≥40 years, recruitment ways from MSM venues, awareness of AIDS knowledge, non-unprotected anal sex in the past 6 months and non-syphilis infection, those who aged 18-24 years (aOR=2.083,95%CI:1.087-3.990), recruitment ways from VCT clinics (aOR=2.125,95%CI:1.175-3.843), unawareness of AIDS knowledge (aOR=2.456,95%CI:1.109-5.437), unprotected anal sex in the past 6 months (aOR=3.553,95%CI:2.143-5.889) and syphilis infection (aOR=2.414,95%CI:1.033-5.462) were higher risk of HIV infection. Conclusion: The new infection rates of HIV were high in MSM in Jiangsu province. Health education, condom use and HIV/syphilis screening promotions should therefore be top priority in the prevention and control of HIV infection in MSM.

[The early graduates from Tongji Medical University(1912-1955)]

The early history of Tongji Medical University can be demonstrated from the graduate certification and the photos of graduates from the Tongji Deutsch Medical School in 1912 to the Wuhan Medical College in 1955. It was found that the names, the chancellors and the affiliations of the university kept changing based on the changing of the names, stamps and signatures of the chancellors on the graduate certificates. It was also found that the apparent morale among graduates appeared to be different during different historical stages in graduate photos. Both graduate certificates and graduate photos show the educational achievements by the Tongji Medical University.

Direct Measurement of the Astrophysical ^{19}F(p,αγ)^{16}O Reaction in the Deepest Operational Underground Laboratory

Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344  keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.

The Intraocular Pressure Lowering Effect of a Dual Kinase Inhibitor (ITRI-E-(S)4046) in Ocular Hypertensive Animal Models

Purpose

The purpose of this study was to develop a preclinical compound, ITRI-E-(S)4046, a dual synergistic inhibitor of myosin light chain kinase 4 (MYLK4) and Rho-related protein kinase (ROCK), for reducing intraocular pressure (IOP).

Methods

ITRI-E-(S)4046 is an amino-pyrazole derivative with physical and chemical properties suitable for ophthalmic formulation. In vitro kinase inhibition was evaluated using the Kinase-Glo Luminescent Kinase Assays. A comprehensive kinase selectivity analysis of ITRI-E-(S)4046 was performed using the KINOMEscan assay from DiscoverRx. The IOP reduction and tolerability of ITRI-E-(S)4046 were assessed in ocular normotensive rabbits, ocular normotensive non-human primates, and ocular hypertensive rabbits. In vivo studies were conducted to assess drug concentrations in ocular tissue. The adverse ocular effects of rabbit eyes were evaluated following the OECD405 guidelines.

Results

ITRI-E-(S)4046 showed highly selective kinase inhibitory activity against ROCK1/2, MYLK4, and mitogen-activated protein kinase kinase kinase 19 (MAP3K19), with high specificity against protein kinase A, G, and C families. In ocular normotensive rabbits and non-human primates, the mean IOP reductions of 0.1% ITRI-E-(S)4046 eye drops were 29.8% and 28.5%, respectively. In hypertonic saline-induced and magnetic beads-induced ocular hypertensive rabbits, the mean IOP reductions of ITRI-E-(S)4046 0.1% eye drops were 46.9% and 22.0%, respectively. ITRI-E-(S)4046 was well tolerated with only temporary and minor signs of hyperemia.

Conclusions

ITRI-E-(S)4046 is a novel type of highly specific ROCK1/2 and MYLK4 inhibitor that can reduce IOP in normotensive and hypertensive animal models. It has the potential to become an effective and well-tolerated treatment for glaucoma.

Hyperspectral Imaging Combined with Artificial Intelligence in the Early Detection of Esophageal Cancer

Simple Summary

Detection of early esophageal cancer is important to improve patient survival, however, early diagnosis of the cancer cells is difficult, even for experienced endoscopists. This article provides a new method by using hyperspectral imaging and a deep learning diagnosis model to classify and diagnose esophageal cancer using a single-shot multibox detector. The accuracy of the results when using an RGB image in WLI was 83% and while using the spectrum data the accuracy was increased to 88%. There was an increase of 5% in WLI. The accuracy of the results when using an RGB image in NBI was 86% and while using the spectrum data the accuracy was increased to 91%. There was an increase of 5% in NBI. This study proves that the accuracy of prediction when using the spectrum data has been significantly improved and the diagnosis of narrow-band endoscopy data is more sensitive than that of white-light endoscopy.

Abstract

This study uses hyperspectral imaging (HSI) and a deep learning diagnosis model that can identify the stage of esophageal cancer and mark the locations. This model simulates the spectrum data from the image using an algorithm developed in this study which is combined with deep learning for the classification and diagnosis of esophageal cancer using a single-shot multibox detector (SSD)-based identification system. Some 155 white-light endoscopic images and 153 narrow-band endoscopic images of esophageal cancer were used to evaluate the prediction model. The algorithm took 19 s to predict the results of 308 test images and the accuracy of the test results of the WLI and NBI esophageal cancer was 88 and 91%, respectively, when using the spectral data. Compared with RGB images, the accuracy of the WLI was 83% and the NBI was 86%. In this study, the accuracy of the WLI and NBI was increased by 5%, confirming that the prediction accuracy of the HSI detection method is significantly improved.

[Diagnosis and treatment of two imported cases with schistosomiasis haematobia in Fujian Province]

OBJECTIVE

To analyze the diagnosis and treatment of two imported cases with schistosomiasis haematobia, so as to provide insights into improving the diagnosis and treatment and avoiding misdiagnosis and mistreatment of imported schistosomiasis haematobia.

METHODS

The medical records and epidemiological data pertaining to the two cases were collected. The stool and urine samples were collected for identification of Schistosoma eggs using the Kato-Katz technique and direct smear method after centrifugal precipitation, and blood samples were collected for detection of anti-Schistosoma antibody. Following definitive diagnosis, the patients were given praziquantel therapy.

RESULTS

The patient 1, a Malagasy, was infected in Madagascar and returned to China for delivery. The case presented intermittent painless terminal hematuria symptoms, and showed no remarkable improvements following multiple-round treatments in several hospitals. In January 2017, she was found to be positive for anti-Schistosoma antibody, negative for feces test, and positive for S. haematobium eggs in urine test, and miracidia were hatched from eggs. Then, the case was diagnosed as schistosomiasis haematobia. Patient 2 worked in Republic of Malawi for many years, and presented intermittent painless terminal hematuria since October 2018; however, no definite diagnosis or effective treatment was received after admission to multiple hospitals. In March 2019, pathological examinations showed a number of eggs in the interstitium of the bladder mass, accompanied by a large number of eosinophils, which was consistent with schistosomiasis cystitis. In April 2019, he was tested positive for serum anti-Schistosoma antibody, negative for the fecal test, and had S. haematobium eggs in urine samples, with miracidia hatched from eggs. Then, the case was diagnosed as schistosomiasis haematobia. Following treatment with praziquantel at a dose of 60 mg/kg, all symptoms disappeared.

CONCLUSIONS

Overseas imported schistosomiasis haematobia is likely to be misdiagnosed. The training pertaining to schistosomiasis control knowledge requires to be improved among clinical professionals, in order to avoid misdiagnosis and mistreatment.

Aldehyde Dehydrogenase Mutation Exacerbated High-Fat-Diet-Induced Nonalcoholic Fatty Liver Disease with Gut Microbiota Remodeling in Male Mice

Simple Summary

ALDH2, mitochondrial aldehyde dehydrogenase 2, is a critical enzyme involved in ethanol clearance in acetaldehyde metabolism. The prevalence of the ALDH2*2 variant is 45% in the Taiwanese population. ALDH2 reportedly has protective properties on myocardial damage, stroke, and diabetic retina damage. However, the effects of ALDH2 in modulation of metabolic syndromes remain unclear. The study evaluated the roles of ALDH2 in a high-fat-diet-induced metabolic syndrome in mice. We explored the effects of ALDH2 gene on NAFLD and potential association with gut microbiota.

Abstract

Mitochondrial aldehyde dehydrogenase 2 (ALDH2) is a critical enzyme involved in ethanol clearance in acetaldehyde metabolism and plays a key role in protecting the liver. The ALDH2*2 mutation causes a significant decrease in acetaldehyde scavenging capacity, leading to the accumulation of acetaldehyde after consuming alcohol. The prevalence of the ALDH2*2 variant is in 45% of Taiwanese individuals. ALDH2 reportedly has protective properties on myocardial damage, stroke, and diabetic retina damage. However, the effects of ALDH2 in the modulation of metabolic syndromes remain unclear. This study evaluates the roles of ALDH2 in a high-fat-diet-induced metabolic syndrome in mice. Male (M) and female (F) wild-type (WT) and ALDH2 knock-in C57BL/6J mice (4–5 weeks old) were fed a high-fat diet for 16 weeks. Results showed that the body and white-adipose-tissue weights were significantly increased in ALDH2-M compared to those in the other groups. We observed markedly elevated serum levels of alanine transaminase and glucose. Oral glucose-tolerance test and homeostasis-model assessment of insulin resistance (HOMA-IR) values were significantly higher in ALDH2-M mice than those in WT-M mice, with no observable differences in female mice. Abundant steatosis and inflammatory cells were observed in ALDH2-M, with significantly decreased expression of hepatic genes IRS2, GLUT4, and PGC-1α compared to that in WT-M. ALDH2 gene mutation also affected the β-diversity of gut microbiota in ALDH2-M resulting in the decreased abundance of Actinobacteria and an increase in Deferribacteres. Our results suggest that potential changes in gut microbiota may be associated with the defective ALDH2 exacerbation of high-fat-diet-induced liver diseases in male mice. However, female mice were not affected, and sex hormones may be an important factor that requires further investigation.

High Serum Elafin Prediction of Poor Prognosis of Locoregional Esophageal Squamous Cell Carcinoma

Simple Summary

Conventional serum markers such as carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC), and tissue polypeptide antigen (TPA) have a low sensitivity in predicting the prognosis of locoregional esophageal squamous cell carcinoma cell (ESCC). In our clinical study, we found high serum elafin to be an independent outcome predictor for stage I-IIIA ESCC, considering T, N, overall stage, and treatment. In vitro experiments showed that adding recombinant elafin drove ESCC cell proliferation, migration and invasion, while shRNA attenuated elafin levels, abrogating those effects. Our results suggested serum elafin might be a noninvasive biomarker to predict the outcome of locoregional ESCC and could potentially be used as a therapeutic target.

Abstract

Esophageal squamous cell carcinoma (ESCC) is a highly aggressive tumor known to have locally advanced and metastatic features which cause a dismal prognosis. We sought to determine whether elafin, a non-invasive and secretory small-molecule marker, could be used to predict prognosis in locoregional ESCC patients in human and in vitro studies. In our human study, 119 subjects were identified as having incident and pathologically-proved ESCC with stage I-IIIA tumors from southern Taiwan between 2000 and 2016. We measured their serum elafin levels at baseline and followed them until the date of cancer death or until January 2020, the end of this study. Those with high serum elafin levels were found to have a 1.99-fold risk (95% confidence interval: 1.17–3.38) shorter survival than those who did not. In our in vitro experiments, elevated elafin levels were found to drive ESCC cell proliferation, migration and invasion, while attenuation of elafin level by shRNA abrogated those effects. We concluded that elafin promotes ESCC motility and invasion and leads to a worse clinical prognosis in ESCC patients without distant metastasis.

Inhibition of Retinal Ganglion Cell Loss By a Novel ROCK Inhibitor (E212) in Ischemic Optic Nerve Injury Via Antioxidative and Anti-Inflammatory Actions

Purpose

This study investigated the neuroprotective effects of administration of ROCK inhibitor E212 on ischemic optic neuropathy.

Methods

Rats received an intravitreal injection of either E212 or PBS immediately after optic nerve infarct. The oxidative stress in the retina was detected by performing superoxide dismutase activity and CellROX assays. The integrity of retinal pigment epithelium was determined by staining of zona occludens 1. The visual function, retinal ganglion cell (RGC) density, and RGC apoptosis were determined by using flash visual-evoked potential analysis, retrograde FluoroGold labeling, and TdT-dUTP nick end-labeling assay. Macrophage infiltration was detected by staining for ED1. The protein levels of TNF-α, p-CRMP, p-AKT1, p-STAT3, and CD206 were evaluated using Western blotting.

Results

Administration of E212 resulted in a 1.23-fold increase in the superoxide dismutase activity of the retina and 2.28-fold decrease in RGC-produced reactive oxygen species as compared to the levels observed upon treatment with PBS (P < 0.05). Moreover, E212 prevented the disruption of the blood-retinal barrier (BRB) in contrast to PBS. The P1-N2 amplitude and RGC density in the E212-treated group were 1.75- and 2.05-fold higher, respectively, than those in the PBS-treated group (P < 0.05). The numbers of apoptotic RGCs and macrophages were reduced by 2.93- and 2.54-fold, respectively, in the E212-treated group compared with those in the PBS-treated group (P < 0.05). The levels of p-AKT1, p-STAT3, and CD206 were increased, whereas those of p-PTEN, p-CRMP2, and TNF-α were decreased after treatment with E212 (P < 0.05).

Conclusions

Treatment with E212 suppresses oxidative stress, BRB disruption, and neuroinflammation to protect the visual function in ischemic optic neuropathy.

Highly efficient polarization-entangled photon-pair generation in lithium niobate waveguides based on bound states in continuum

Integrated optics provides a platform for the experimental implementation of highly complex and compact circuits for practical applications as well as for advances in the fundamental science of quantum optics. The lithium niobate (LN) waveguide is an important candidate for the construction of integrated optical circuits. Based on the bound state in the continuum (BIC) in a LN waveguide, we propose an efficient way to produce polarization-entangled photon pairs. The implementation of this method is simple and does not require the polarization process needed for periodically poled LN. The generation rate of the entangled photon pairs increases linearly with the length of the waveguide. For visible light, the generation efficiency can be improved by more than five orders of magnitude with waveguides having the length of only a few millimeters, compared with the corresponding case without BICs. The phenomena can appear in a very wide spectrum range from the visible to THz regions. This study is of great significance for the development of active integrated quantum chips in various wavelength ranges.

Magnetotransport in hybrid InSe/monolayer graphene on SiC

The magnetotransport properties of a hybrid InSe/monolayer graphene in a SiC system are systematically studied. Compared to those of its bare graphene counterpart, in InSe/graphene, we can effectively modify the carrier density, mobility, effective mass, and electron-electron (e-e) interactions enhanced by weak disorder. We show that in bare graphene and hybrid InSe/graphene systems, the logarithmic temperature (lnT) dependence of the Hall slope R _H = δR _xy /δB = δρ _xy /δB can be used to probe e-e interaction effects at various temperatures even when the measured resistivity does not show a lnT dependence due to strong electron-phonon scattering. Nevertheless, one needs to be certain that the change of R _H is not caused by an increase of the carrier density by checking the magnetic field position of the longitudinal resistivity minimum at different temperatures. Given the current challenges in gating graphene on SiC with a suitable dielectric layer, our results suggest that capping a van der Waals material on graphene is an effective way to modify the electronic properties of monolayer graphene on SiC.

Mining Gut Microbiota From Bariatric Surgery for MAFLD

The progression of metabolic dysfunction associated fatty liver disease (MAFLD) leads to steatohepatitis, liver fibrosis and hepatocellular carcinoma. Thus far, there have been no FDA-approved medications for MAFLD. Bariatric surgery (BS) has been found to improve insulin resistance, steatohepatitis and liver fibrosis but is not recommended for treating MAFLD due to its invasiveness. Recent studies suggest the improved glucose metabolism after BS is a result of, at least partly, alterations to the gut microbiota and its associated metabolites, including short chain fatty acids and bile acids. It makes sense the improved steatohepatitis and fibrosis after BS are also induced by the gut microbiota that involves in host metabolic modulation, for example, through altering bile acids composition. Given that the gut-liver axis is a path that may harbor unexplored mechanisms behind MAFLD, we review current literatures about disentangling the metabolic benefits of MAFLD after BS, with a focus on gut microbiota. Some useful research tools including the rodent BS model, the multiomics approach, and the human microbiota associated (HMA) mice are presented and discussed. We believe, by taking advantage of these modern translational tools, researchers will uncover microbiota related pathways to serve as potential therapeutic targets for treating MAFLD.

Toll-like receptor 4 prevents AOM/DSS-induced colitis-associated colorectal cancer in Bacteroides fragilis gnotobiotic mice

Bacteroides fragilis (BF) plays a critical role in developing and maintaining the mammalian immune system. We previously found that BF colonization could prevent inflammation and tumor formation in a germ-free (GF) colitis-associated colorectal cancer (CAC) mouse model. The role of Toll-like receptor 4 (TLR4) in CAC development has not been clearly elucidated in BF mono-colonized gnotobiotic mice. The wild-type (WT) and TLR4 knockout (T4K) germ-free mice were raised with or without BF colonization for 28 days (GF/WT, GF/T4K, BF/WT, and BF/T4K) and then CAC was induced under azoxymethane (AOM)/dextran sulfate sodium (DSS) administration. The results showed that tumor formation and tumor incidence were significantly inhibited in the BF/WT group compared to those observed in the GF/WT group. However, the tumor prevention effect was not observed in the BF/T4K group unlike in the BF/WT group. Moreover, the CAC histological severity of the BF/WT group was ameliorated, but more severe lesions were found in the GF/WT, GF/T4K, and BF/T4K groups. Immunohistochemistry showed decreased cell proliferation (PCNA, β-catenin) and inflammatory markers (iNOS) in the BF/WT group compared to those in the BF/T4K group. Taken together, BF mono-colonization of GF mice might prevent CAC via the TLR4 signal pathway.

Benchmark Experiment to Prove the Role of Projectile Excited States Upon the Ion Stopping in Plasmas

We report on a precision energy loss measurement and theoretical investigation of 100  keV/u helium ions in a hydrogen-discharge plasma. Collision processes of helium ions with protons, free electrons, and hydrogen atoms are ideally suited for benchmarking plasma stopping-power models. Energy loss results of our experiments are significantly higher than the predictions of traditional effective charge models. We obtained good agreement with our data by solving rate equations, where in addition to the ground state, also excited electronic configurations were considered for the projectile ions. Hence, we demonstrate that excited projectile states, resulting from collisions, leading to capture-, ionization-, and radiative-decay processes, play an important role in the stopping process in plasma.

[A comparative study on the construction methods of animal models of aortic arch dissection]

Objective: To compare the effectiveness and safety of different methods to construct animal models of aortic arch dissection (AAD), and explore safe and effective methods for constructing AAD animal models. Methods: Twenty-four healthy mongrel dogs were divided into 4 groups by random number table (n=6). Group A: Venous incision needle high pressure water flow impact method; Group B: Venous incision needle non-high pressure water flow impact method; Group C: Transarterial sheath non-high pressure water flow impact method; Group D: Two-way balloon expansion combined with elastase perfusion method. Imaging examinations were performed immediately and 7 days after operation, aortic tissue biopsy and pathological staining were performed 15 days after operation to observe the formation of AAD. The operation time, aortic blood flow block time, model construction success rate, dissection tear length, postoperative survival rate and survival time of four groups of experimental dogs were collected to compare the effectiveness and safety of different construction methods. Results: There were no significant difference of the gender, age and weight between four groups of experimental dogs (all P>0.05). The operation time of four groups of experimental dogs were (111.6±8.0), (168.0±17.4), (164.4±13.9), (202.8±21.5)min, and the difference was statistically significant (F=39.973, P<0.001). The operation time of group A was significantly lower than group B, C and D (all P<0.001). The aortic blood flow block time of four groups of experimental dogs were (5.2±1.8), (19.6±3.8), (20.6±3.9), and (18.6±3.0) min, and the difference was statistically significant (all P<0.001). The aortic blood flow block time of group A was significantly lower than group B, C and D (F=27.598, P<0.001). The four groups of experimental dogs had 5, 5, 4, and 1 model were successfully constructed, respectively, and the difference was statistically significant (P=0.008). The successful rate of model construction in group A was significantly higher than that in group D (P=0.040). The dissection tear length of four groups were (14.4±3.0), (11.3±4.2), (7.0±2.3), (4.7±0.6) cm,and the difference was statistically significant (F=8.103, P=0.003). The dissection tear length of group A was significantly longer than group C, D (all P<0.05). The postoperative survival time were 15.0(10.0, 15.0), 5.0(3.0, 10.0), 3.5(1.5, 4.8), 10.0(2.8, 15.0) days, and the difference was statistically significant (χ²=7.825,P=0.036). The postoperative survival time of group A was significantly higher than group B, C (all P<0.05). There was no significant difference in the survival rate of the four groups (P=1.000). The pathological staining results showed that the elastic fiber at the tearing point of AAD was destroyed, and the elastic fiber on the outer wall of the false cavity was over-stretched, which was consistent with the pathological changes of aortic dissection. Conclusion: Transvenous incision needle high-pressure water flow impact modeling method is easy to operate. The aortic blood flow block time is short, the dissection tear length is wide, and the postoperative survival time is long, can be used as the preferred method of animal AAD model construction.