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Background: Necrotizing enterocolitis (NEC) is a neonatal intestinal necrotizing disease caused by various factors in newborns. Sulforaphane (SFN) has a strong anti-inflammatory ability and a certain protective effect on intestinal diseases. Objective: NEC is a common developed gastrointestinal exigency in untimely baby. SFN is a naturally originated isothiocyanate that has beneficial effects on the intestinal system.The purpose of this study is to study the protective effect of SFN on endoplasmic reticulum stress (ERS)-related NEC. Methods: The newborn mice were randomly divided into control (n=15), NEC (n=20), and NEC+SFN (n=18) groups. Mice in NEC and SFN+NEC groups were injected with 0.1 μl normal saline or 20 mg/kg/d SFN, respectively. After that, the weight and survival in the mice were recorded every day. Then the mice were sacrificed after the 96 h of modeling, ileum tissue and blood samples were collected for qPCR, Western blot, ELISA, HE staining, TUNEL staining, immunohistochemistry assays. Results: Results: SFN significantly inhibited the mRNA expression of BIP, CHOP, IL-1β and IL-6, and protein expression of Bax, Caspase-3, Caspase-9 and CHOP, and promoted the expression of Bcl-2 in ER-induced NEC mice intestinal tissues (P Conclusion: SFN could effectively protect ERS-induced inflammation and apoptosis in NEC mice.

Multitask measurements with different measuring ranges and resolutions have put forward higher requirements for force sensors. This paper presents a novel variable configuration approach to develop an adjustable resolution force sensor with a compact force-sensitive structure. Unlike the traditional strain gauge-based force measurement, the external force is detected through measuringthe displacement of the deformed structure with a precision optical linear encoder. This approach can enable variable measuring range and force resolution through the continuous adjustment of structural stiffness. Specifically, the stiffness adjustment is implemented by changing the second moment of area of the sensor structure through rotating its build-in flexure beam shafts. Analytical models are established to provide the theoretical basis for analysis and design of the sensor. Further, the validity of the design is evaluated with finite element simulations. Finally, a sensor prototype is developed for performance evaluation and applied for the wire bond pull tests to evaluate the bond strength on the printed circuit board assembly. Experimental results show that it is effective to change the measuring range and force resolution of the developed force sensor through the stiffness adjustment.

The flexibility to choose the halogen of a hybrid perovskite provides a versatile platform to study the optical properties of two-dimensional perovskites.

To protect the grassland ecosystem’s security, and coordinate the utilisation of grassland resources, explicitly estimating the response of Net Primary Productivity (NPP) of 10 grassland groups to future climate change is necessary. Based on the Comprehensive and Sequential Classification System (CSCS) and modified Carnegie Ames Stanford Approach (CASA) model, in conjunction with four Representative Concentration Pathways (RCP 2.6, RCP 4.5, RCP 6.0, RCP 8.5) of the Intergovernmental Panel on Climate Change (IPCC), the response of China’s grassland NPP to climate change was simulated and estimated. Results showed that: (1) the simulation accuracy of modified CASA model (R2 = 0.65) is 34% higher than that of CASA model, indicating that the modified CASA was suitable for estimating grassland NPP in China; (2) annual mean NPP and total NPP (2001–18) were 138.4 g C m−2 year−1 and 495.7 T g C, respectively; compared with the period 2001–18, NPP during the 2050 under RCP 2.6, RCP 4.5, RCP 6.0 and RCP 8.5 were predicted with increases of 34.8%, 35.9%, 34.9% and 35.8%, respectively; and (3) from the present-day to the 2050, the NPP of Warm desert exhibited the largest increase (73.2–76.3%), while that of Tundra and alpine grassland the smallest (1.3–1.6%). These differences in NPP increase likely lead to differences in grassland carrying capacity. To respond to the impact of future climate change on grassland, grassland classification management strategies according to different groups should be implemented as grassland NPP changes differently in different grassland groups.

In this paper, a time-varying controller is developed for Euler-Lagrange systems with bounded disturbances. A mapping strategy is designed to make the convergence time of the system achieve at an arbitrarily pre-assigned finite time. The selection of the time period is independent of the initial conditions, and the performances is free of chattering. To be specific, the proposed controller is constructed in two steps: Firstly, a common PD controller is designed to ensure the asymptotical stability of the nominal system; Secondly, by employing the mapping strategy, then the obtained new controller can make the disturbed system converged at a specified time. In the simulations, a two-link manipulator is used to validate that both uniformly stability for the undisturbed system and pre-assigned time attraction for the disturbed system can be achieved.

The rapid development of computer technology and robot technology in recent years makes it possible for robotic arm to replace manual work to carry out dangerous live work, which will greatly improve the efficiency of maintaining electric power facilities, shorten maintenance time and protect workers’ safety. Aiming at the control of manipulators, an iterative learning control algorithm based on variable length and time-varying system is developed in this paper. This method can well solve the problem of different operating time of live-line operation of manipulator, and improve the limitations of original iterative control laws that each iteration time is required to keep same to adapt to the actual working conditions. Specifically, this paper is divided into two parts: Firstly, machine vision is used to locate the spatial relationships among the manipulator base, the manipulator actuator, and the target to be worked; Then, a novel iterative learning control schemes are constructed for the tracking control purpose.

Organophosphate esters (OPEs) are a kind of emerging pollutants. Tree rings are long-lasting reservoirs of OPEs in the environment and can be analyzed to indicate OPEs contamination in the sampling region. Currently, research on OPEs in tree rings is still limited. In this study, tree rings of 5 arbor species from Sichuan Province, China, were sampled to study the occurrence and distribution of 6 OPEs, which were quantitatively analyzed by gas chromatography- mass spectrometry (GC-MS). The total concentrations of OPEs in all samples ranged from 189.79 (Fir species) to 341.23 ng/g (Toona sinensis), with average concentration of 284.77 ± 46.66 ng/g. The concentrations of OPEs in the 5 arbor species showed no significant difference. Tree rings of arbor species could be used as good passive samplers to show the occurrence and distribution of OPEs in the regional environment. Tris(2-butoxyethyl) phosphate (TBEP) was the dominant OPEs followed by tri(2-chloroethyl) phosphate (TCEP). Tris (2-ethylhexyl) phosphate (TEHP) and tri-n-butyl phosphate (TnBP) showed relatively stable concentrations in each arbor species, while the other 4 OPEs including TBEP, triphenyl phosphate (TPhP), tri(chloropropyl) phosphate (TCPP) and TCEP had significantly different concentrations. Interestingly, the absorption and accumulation of OPEs by tree rings of arbor species was quite different from that of inorganic elements reported by other studies.

Organophosphate esters (OPEs) are a kind of emerging pollutants. Tree trunks are long-lasting reservoirs of OPEs in the environment. Using tree rings to study the temporal and spatial distribution characteristics of emerging pollutants - OPEs has a good indication of the use of OPEs in the region, and provides scientific support for the prevention and control of emerging pollutants such as OPEs. At present, the research on OPEs in tree rings is almost blank. In this study, gas chromatography-tandem mass spectrometry (GC-MS) was used to quantitatively analyze 6 kinds of OPEs in tree rings of 5 tree species from Sichuan Province, China. Its distribution characteristics and inter-annual variation were discussed and the pollution process of OPEs in this area was inferred. The results showed that Σ6OPEs concentration in tree rings ranged from 189.79 (Fir) to 341.23 ng/g (Toona sinensis), with an average of 284.77 ± 46.66 ng/g. There was no significant difference in the distribution of OPEs among the 5 kinds of trees and the dominant monomer was TBEP resulting that arbor could be seen as a good passive sampler to show the historical changes of OPEs in the regional environment. Interestingly, the absorption and accumulation of arbors to OPEs was quite different from that to inorganic elements reported by other studies. Concentrations of TEHP and TnBP in each ring sample of the 5 arbor species were stable, while concentrations of the other 4 monomers fluctuated significantly.

Clarification of the direction of China’s future agricultural structural transformation is important, particularly by analysing the dynamic characteristics of upgrading the food consumption structure, especially the relationship between grain and grass-fed livestock products, and by predicting future food consumption patterns. Based on the food equivalent unit (FEU) and the arable land equivalent unit (ALEU), characteristics of meat consumption elasticity across China and between regions were analysed using the extend linear expenditure system for national meat consumption elasticity and regional changes. Similarly, in addition to the substitution effect of grass-fed livestock products on grain-fed livestock products, the prediction of the future gap in demand for grass-fed livestock products was explored. Results indicated that: (1) from 2005 to 2012, the per-capita food consumption on average has stabilised at 460 kg FEU per year. The consumption of grain-fed livestock products is stable, and that for grass-fed livestock products has increased dramatically since 2000; (2) there is a substitution effect of consumption of grass-fed on consumption of grain-fed livestock products on individual and regional scales; (3) By 2035, the overall demand gap for future grass-fed livestock products in China will be 1.14 × 1010 kg, and the main demand will be in grain farming areas. Based on the aggregated advantage index of each region, the seven grassland ecological-economic regions are divided into three priority groups for grassland agricultural development.

Visceral myopathy is a rare genetic disorder that commonly affects the digestive and renal systems. Manifestations include a clinical spectrum covering chronic intestinal pseudo-obstruction (CIPO) and megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS). The smooth muscle actin γ-2 gene (ACTG2) is one of the most common disease-causing genes. Here, we present a case of pediatric intestinal pseudo-obstruction associated with a novel missense ACTG2 mutation, c.588G>C/p.E196D. His parents had no this mutation, which suggested the possibility of spontaneous mutation. Amino acid conservation analysis of γ-2 actin showed replacement of glutamate at position 196 by aspartate. The patient suffered from recurrent episodes of abdominal bloating, undergone repeated gastrointestinal surgery, had feeding difficulties, and required long-term parenteral nutrition support. The patient had no other specific symptoms or underlying diseases. X-ray of the abdomen showed dilation of the intestine as well as an air-fluid pattern. The manifestations of biopsy were various. All biochemical tests were normal, and the possibility of secondary intestinal pseudo-obstruction was excluded. The mutation site of ACTG2 in the present study has not been previously described in patients with visceral myopathy, and thus, our study reveals a novel mutation of ACTG2-associated visceral myopathy in a patient with CIPO. This report can serve as a reference for future research and further expands the map of genetic variation for visceral myopathy.

Objective To investigate the expression of chromosome 6 open reading frame 15 (C6orf15) in colon cancer and its effects on clinicopathological features and prognosis. Methods Using the transcriptome and clinical data of colon cancer and normal tissues in The Cancer Genome Atlas (TCGA) database, the expression of C6orf15 mRNA in colon cancer samples and its relationship with clinicopathological characteristics and prognosis were explored. The expression level of C6orf15 protein in 23 colon cancer tissues was detected by immunohistochemistry (IHC). The possible mechanism of C6orf15 involved in the occurrence and development of colon cancer was explored by gene set enrichment analysis (GSEA). Results Compared with normal tissues, C6orf15 was highly expressed in colon cancer (1.207±0.694 vs. 0.276±0.166, t=8.281, PP=0.04), lymph node metastasis (χ2=36.97, PP=0.003), pathological stage (χ2=34.17, PPP=0.023) and lymph node metastasis (P=0.048). Conclusion C6orf15 is highly expressed in colon cancer tissue and is related to adverse pathological features and poor prognosis of colon cancer. It is involved in multiple oncogenic signaling pathways and may serve as a prognostic marker of colon cancer.

Staplers have been widely used in the clinical treatment of gastrointestinal reconstruction. However, the current titanium (Ti) staple will remain in the human body permanently, resulting in some adverse effects. In this study, we developed a type of biodegradable staple for colonic anastomosis using 0.3 mm diameter magnesium (Mg) alloy wires. The wire surface was modified by micro-arc oxidation treatment (MAO) and then coated with poly-l-lactic acid (PLLA) to achieve a moderate degradation rate matching the tissue healing process. The results of tensile tests on isolated porcine colon tissue anastomosed by Mg and Ti staples showed that the anastomotic property of Mg staples was almost equal to that of Ti staples. The

This paper proposes a new three-tube structure to replace the original steel tube. The vortex-induced vibration of the three-tube structure is simulated by two-way fluid-structure coupling. With the control variable method, the simulation calculation of multiple groups of three-pipe structures under uniform incoming flow at different wind speeds is carried out. By analyzing the vortex kinetic energy diagram and displacement diagram, the best outer diameter and tube center distance of the three-tube structure to suppress vortex-induced vibration in the leeward direction are obtained. By summarizing the situation of a symmetrical vortex, the conditions of the symmetrical vortex are understood. Then, by comparing the amplitude of the vortex-induced vibration of the original structure with that of the three-tube structure, the three-tube structure is further optimized to obtain a new structural design that can effectively control vortex-induced vibration.

Objective. Necrotizing enterocolitis (NEC) is one of the commonest gastrointestinal critical diseases in newborns. Several researches have proven the efficacy of melatonin (MEL) on NEC, but the latent mechanisms were ambiguous. We designed the current research to evaluate the function and mechanism of MEL on NEC in a neonatal mouse model. Methods. The newborn mice were subjected to formula milk containing LPS and hypoxia to establish a NEC model and also intraperitoneally injected with MEL. During the experiment, all mice were closely monitored and weighed. The effect of MEL on the histopathological injury of the terminal ileum tissues, inflammation, and oxidative stress of serum in NEC mice was examined by hematoxylin-eosin (H&E) staining and ELISA. The effect of MEL on the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome was assessed via quantitative real-time PCR and Western blot. Results. MEL intensified the survival rate and body weight in NEC mice. The H&E staining illustrated that MEL improved the histopathological injury in NEC mice. Moreover, MEL repressed the IL-1β, TNF-α, and MDA levels of serum and enhanced the SOD and GSH-Px levels of serum in NEC mice. We also discovered that MEL attenuated the mRNA and protein levels of NLRP3, Toll-like Receptor 4 (TLR4), NF-κB, and caspase-1 of the terminal ileum tissues in NEC mice. Conclusion. Our research illuminated that MEL attenuated the severity of NEC via weakening the activation of the NLRP3 inflammasome.

The rapid emergence of SARS-CoV-2 mutants with new phenotypic properties is a critical challenge to the control of the ongoing pandemic. B.1.1.7 was monitored in the UK through routine testing and S-gene target failures (SGTF), comprising over 90% of cases by March 2021. Now, the reverse is occurring: SGTF cases are being replaced by an S-gene positive variant, which we associate with B.1.617.2. Evidence from the characteristics of S-gene positive cases demonstrates that, following importation, B.1.617.2 is transmitted locally, growing at a rate higher than B.1.1.7 and a doubling time between 5-14 days. S-gene positive cases should be prioritised for sequencing and aggressive control in any countries in which this variant is newly detected.One-Sentence SummaryThe B.1.617.2 variant of SARS-CoV-2 is replacing B.1.1.7 and emerging as the dominant variant in England, evidenced by sustained local transmission.

Herein, we compared the risk factors, clinical presentation of patients hospitalized with SARS-CoV-2, SARS-CoV, or MERS-CoV infection. Our data sources include PubMed, Embase, CNKI, and Ovid/Medline. The proportion of male patients with COVID-19 was higher than who with SARS but lower than who with MERS (p

The isomerization of photoresponsive molecules in the solid state is always restricted due to the intermolecular stacking. In this work, we fabricated solid powdery materials with fast and efficient photochromism by embedding donor-acceptor Stenhouse adducts (DASAs) into the nanocages of metal-organic frameworks (MOFs). Visible light irradiation (530 nm, 40 mW/cm2) induces linear-to-cyclic isomerization of DASAs in ~7.7 s with a 100% conversion efficiency, which is with the same order of magnitudes as that in solution. Meanwhile, the isomerization of loaded DASAs is fully reversible after repeated treating by visible light and heat. The microenvironment in the nanocages of MOFs is able to promote the isomerization to either linear or cyclic DASAs, which was unfold by density functional theory calculations. All in all, the solid powdery materials are further applied as additives to realize photochromism of bulk materials, which show reversible color change under visible light and heat.

Background: Among the numerous bond-forming patterns, C–C bond formation is one of the most useful tools for building molecules for the chemical industry as well as life sciences. Recently, one of the most challenging topics is the study of the direct coupling reactions via multiple C–H bond cleavage/activation processes. A number of excellent reviews on modern C–H direct functionalization have been reported by Bergman, Bercaw, Yu and others in recent years. Among the large number of available methodologies, Pdcatalyzed reactions and hypervalent iodine reagent mediated reactions represent the most popular metal and non-metal involved transformations. However, the comprehensive summary of the comparison of metal and non-metal mediated transformations is still not available. Objective: The review focuses on comparing these two types of reactions (Pd-catalyzed reactions and hypervalent iodine reagent mediated reactions) based on the ways of forming new C–C bonds, as well as the scope and limitations on the demonstration of their synthetic applications. Conclusion: Comparing the Pd-catalyzed strategies and hypervalent iodine reagent mediated methodologies for the direct C–C bond formation from activation of C-H bonds, we clearly noticed that both strategies are powerful tools for directly obtaining the corresponding pruducts. On one hand, the hypervalent iodine reagents mediated reactions are normally under mild conditions and give the molecular diversity without the presence of transition-metal, while the Pd-catalyzed approaches have a broader scope for the wide synthetic applications. On the other hand, unlike Pd-catalyzed C-C bond formation reactions, the study towards hypervalent iodine reagent mediated methodology mainly focused on the stoichiometric amount of hypervalent iodine reagent, while few catalytic reactions have been reported. Meanwhile, hypervalent iodine strategy has been proved to be more efficient in intramolecular medium-ring construction, while there are less successful examples on C(sp3)–C(sp3) bond formation. In summary, we have demonstrated a number of selected approaches for the formation of a new C–C bond under the utilization of Pd-catalyzed reaction conditions or hyperiodine reagents. The direct activations of sp2 or sp3 hybridized C–H bonds are believed to be important strategies for the future molecular design as well as useful chemical entity synthesis.

Aim We aimed to compare the safety and oncological outcomes of transanal endoscopic microsurgery (TEM) and radical surgery (RS) for patients with T1 or T2 rectal cancer. Method We searched Pubmed, Embase, Cochrane Library databases for relevant studies comparing TEM with RS in rectal cancer published until April 2020. We focused on safety and oncological outcomes. Results This meta-analysis included 3526 patients from 12 studies. Compared with RS, TEM had a shorter operative time (weighted mean difference [WMD] −110.02, 95% confidence interval [CI]: 143.98, −76.06), less intraoperative blood loss (WMD -493.63, 95% CI: 772.66, −214.59), lower perioperative morality (risk ratio [RR] 0.25, 95% CI: 0.06, 0.99), and fewer postoperative surgical complications (RR 0.23, 95% CI: 0.11,0.45). TEM was associated with more patients with a positive margin or a doubtfully complete margin than RS (RR 7.36, 95% CI: 3.66, 14.78). TEM was associated with higher local recurrence (RR 2.63, 95% CI: 1.60, 4.31) and overall recurrence (RR 1.60, 95% CI: 1.09, 2.36). TEM had a negative effect on 5-year overall survival (hazard ratio [HR] 1.51, 95% CI: 1.16, 1.96), especially in the T2 without neoadjuvant therapy (NAT) subgroup (HR 2.02, 95% CI: 1.32, 3.09), but in the subgroups of T1 or T2 with NAT before TEM, TEM did not yield a significantly lower overall survival than RS. Conclusion TEM seems appropriate for T1 rectal cancer with favourable histopathology. For patients with T2 rectal cancer, NAT before TEM may contribute to achieving oncological outcomes equivalent to that achieved with RS.

We report here our latest discovery on the directed lithiation and palladium-catalyzed arylation of anisoles. During this research, the formation of a four-membered lithiumcycle followed by transmetalation to the corresponding palladacycle has been achieved, which is difficult to be obtained from palladium-catalyzed C–H activation processes. This approach has provided an alternative way of introducing functionalities to arenes such as anisoles, thioanisoles, and anilines. This approach also features an excellent monoselectivity compared with reactions under transition-metal-catalyzed conditions.

In applications of Gaussian processes where quantification of uncertainty is a strict requirement, it is necessary to accurately characterize the posterior distribution over Gaussian process covariance parameters. Normally, this is done by means of standard Markov chain Monte Carlo (MCMC) algorithms. Motivated by the issues related to the complexity of calculating the marginal likelihood that can make MCMC algorithms inefficient, this paper develops an alternative inference framework based on Adaptive Multiple Importance Sampling (AMIS). This paper studies the application of AMIS in the case of a Gaussian likelihood, and proposes the Pseudo-Marginal AMIS for non-Gaussian likelihoods, where the marginal likelihood is unbiasedly estimated. The results suggest that the proposed framework outperforms MCMC-based inference of covariance parameters in a wide range of scenarios and remains competitive for moderately large dimensional parameter spaces., Comment: 27 pages

Selenium (Se) is a trace element for human and animal health. Cadmium (Cd) is a known human carcinogen. The effects of Cd on the environment and humans are well known. Because chickens are at the top of the food chain, it is a good experimental animal model for assessing heavy metal toxicity and its potential threat to humans. Selenomethionine (Se-met) is a suitable form for nutritional Se supplementation. Therefore, the toxicity of Cd to the chicken liver and the antagonistic effects of Se-met on Cd were examined at the molecular level in the present study. The results showed that oxidative stress indicators (apoptosis-related genes, P13K/AKT pathway-related genes, and heat shock proteins (HSPs)-related genes) in the Cd group have changed significantly, indicating Cd induced hepatocyte stress and apoptosis. Interestingly, the changes in oxidative stress indicators (apoptosis-related genes, P13K/AKT pathway-related genes, and HSPs-related genes) in the Cd-Se-met group were mitigated compared with the control group. Our results indicated that Cd can induce hepatocyte apoptosis and stress in the chickens. Se-met has an ameliorative effect on Cd-induced apoptosis of chicken hepatocyte by regulating PI3K/AKT pathway. Our findings will provide a new insight for better understanding of the detoxification function of Se-met to heavy metals.

Several previous approaches attempted to predict bursty topics on Twitter. Such approaches have usually reported that the time information (e.g. the topic popularity over time) of hashtag topics contribute the most to the prediction of bursty topics. In this paper, we propose a novel approach to use time features to predict bursty topics on Twitter. We model the popularity of topics as density curves described by the density function of a beta distribution with different parameters. We then propose various approaches to predict/classify the bursty topics by estimating the parameters of topics, using estimators such as Gradient Decent or Likelihood Maximization. In our experiments, we show that the estimated parameters of topics have a positive effect on classifying bursty topics. In particular, our estimators when combined together improve the bursty topic classification by 6.9 in terms of micro F1 compared to a baseline classifier using hashtag content features.