Erratum to“Probing the Interfacial Forces and Surface Interaction Mechanisms in Petroleum Production Processes”[Engineering 18(2022)49-61]

In Ref.[1],Eq.(8)has a typo,the following replacement should be done.γ_(bb)/2rδ/δr(rδ(r,t)/δr=2γ_(bb)/R_(bb)-Þ(t,t)-Ⅱ[h[r,t)](bubble=drop-bubble=drop)The publisher regrets an error in the original–article,and the sentence that explained the equation“Eqs.(8)–(10)show the augmented Young–Laplace equation for the interactions of gas bubbles or liquid droplets in different configurations,where Rb is the bubble/drop radius,Rp is the particle radius,Rbp=(1/Rb+1/Rp)1.

深基坑钢支撑屈曲变形分析

以北京某地铁基坑支护现场的一根严重屈曲变形的钢支撑为研究对象,通过与其相邻钢支撑的监测数据、加载过程等因素进行比较分析,逐步确定其变形原因。首先测试其加载设备是否存在问题,然后分析围护桩深层水平位移以及钢支撑轴力变化等监测数据,推测其变形原因及最早变形时间。为进一步研究钢支撑材料缺陷的影响,基于有限元软件MIDAS/GTS对钢支撑的加载过程进行数值模拟,分析其变形机理。

酪酸梭菌活菌散联合乳果糖、饮食疗法治疗儿童功能性便秘的效果分析

目的探讨酪酸梭菌活菌散+乳果糖+饮食疗法方案治疗儿童功能性便秘的临床效果。方法选取徐州市儿童医院2018年4月—2019年6月门诊接诊的80例功能性便秘患儿为研究对象,按随机数字表法分为两组,对照组(40例)行乳果糖+饮食疗法等常规治疗,观察组(40例)在对照组基础上再加用酪酸梭菌活菌散进行治疗。采用放射免疫法测定P物质水平,采用酶联免疫吸附法测定生长抑素水平;比较两组患儿便质干硬、排便疼痛、排便频率<1次/d的变化情况;比较两组患儿排便恢复正常时间、住院时间、总有效率及相关不良反应发生情况。结果治疗4周后,观察组血清P物质水平高于对照组(P<0.05),生长抑素水平低于对照组(P<0.05);观察组治疗后便质干硬、排便疼痛及排便频率<1次/d发生率低于对照组(P<0.05);观察组排便恢复正常时间、住院时间短于对照组(P<0.05),治疗总有效率高于对照组(P<0.05)。不良反应总发生率与对照组比较,差异无统计学意义(P>0.05)。结论酪酸梭菌活菌散+乳果糖+饮食疗法方案治疗儿童功能性便秘,可改善患儿的胃肠激素水平和临床症状,提高治疗总有效率,且不会引起严重不良反应,具有安全性。

Probing the Interfacial Forces and Surface Interaction Mechanisms in Petroleum Production Processes

Despite the advances that have been made in renewable energy over the past decade,crude oil or petroleum remains one of the most important energy resources to the world.Petroleum production presents many challenging issues,such as the destabilization of complex oil-water emulsions,fouling phenomena on pipelines and other facilities,and water treatment.These problems are influenced by the molecular forces at the oil/water/solid/gas interfaces involved in relevant processes.Herein,we present an overview of recent advances on probing the interfacial forces in several petroleum production processes(e.g.,bitumen extraction,emulsion stabilization and destabilization,fouling and antifouling phenomena,and water treatment)by applying nanomechanical measurement technologies such as a surface forces apparatus(SFA)and an atomic force microscope(AFM).The interaction forces between bitumen and mineral solids or air bubbles in the surrounding fluid media determine the bitumen liberation and flotation efficiency in oil sands production.The stability of complex oil/water emulsions is governed by the forces between emulsion drops and particularly between interface-active species(e.g.,asphaltenes).Various oil components(e.g.,asphaltenes)and emulsion drops interact with different substrate surfaces(e.g.,pipelines or membranes),influencing fouling phenomena,oil-water separation,and wastewater treatment.Quantifying these intermolecular and interfacial forces has advanced the mechanistic understanding of these interfacial interactions,facilitating the development of advanced materials and technologies to solve relevant challenging issues and improve petroleum production processes.Remaining challenges and suggestions on future research directions in the field are also presented.

Advances in Germplasm Resources of Chinese Milk Vetch in China

Chinese milk vetch( Astragalus sinicus L.) is a commonly used green manure crop in paddy fields in southern China and it has the effect of fostering fertility and soil. This paper firstly summarized advances in research of new high quality and yield varieties of germplasm resources of Chinese milk vetch. Then,on the basis of current situation,it came up with recommendations for collection,storage and promotion,as well as application in the current ecological agriculture,including establishing germplasm resource bank and improving germplasm resource evaluation system.

Relations between soil heterogeneity and common reed(Phragmites australis Trin.ex Steud.) colonization in the Keriya River Basin,Xinjiang of China

How common reed(Phragmites australis Trin. ex Steud.) colonization correlates to soil heterogeneity and environmental determinants remains unclear in arid areas. We conducted a field investigation and soil sampling in 100 plots along Keriya River Basin to uncover the relationship between common reed and heterogeneous soils. Reed colonization variables and its soil properties were measured and recorded for the analysis of their relationship using Pearson correlation and redundancy analysis methods. The comparison results of common reed characteristics among 100 plots showed that common reeds performed strong tolerance and ecophysiological plasticity to edaphic stresses. Common reed colonization was tightly connected to soil heterogeneity according to the correlation analysis between its colonization characteristics and soil properties. Common reed colonization got feedbacks on soil properties as well, including the increase of soil organic matter and the alleviation of salt uplifting. The main limiting environmental determinant of common reed colonization was soil salt, followed by pH and soil water content.

Dietary methionine sources and levels modulate the intestinal health status of broiler chickens

Given the key role of methionine in biological processes,adequate methionine should be provided to meet the nutritional requirements.DL-2-hydroxy-4-(methylthio)-butanoic acid(DL-HMTBA)has been considered as an important source of methionine.However,the effects of different sources and levels of methionine on the intestinal health status have not been clarified yet.An experiment was carried out to investigate the effects of different dietary sources and levels of methionine on the intestinal epithelial barrier,inflammatory cytokines expression,ileal morphology,microbiota composition,and cecal short chain fatty acids(SCFA)profiles.For this purpose,720 male Arbor Acre broiler chicks at 1 d old were randomly assigned to a 2×3 factorial arrangement with 2 methionine sources(DL-methionine and DLHMTBA)and 3 total sulfur amino acids(TSAA)levels(80%,100%,and 120%of Arbor Acre recommendation).The results showed that DL-HMTBA supplementation promoted intestinal physical barrier at both gene expression level of claudin-1 and serum diamine oxidase level(P<0.05),and the inflammatory cytokine IL-6 m RNA expression was down-regulated by dietary DL-HMTBA supplementation compared with the DL-methionine group(P<0.05).Meanwhile,an upregulated gene expression of claudin-1 and zonula occluden-1(ZO-1)were observed in the low-TSAA treatment on d 14(P<0.05),whereas this treatment increased the expression of IL-1βand IL-6(P<0.05).Villus height to crypt depth ratio was high(P<0.05)in the middle-level TSAA group.Furthermore,DL-HMTBA supplementation optimized the microbiota of the ileum especially the relative abundance of Lactobacillus,where the digestion and absorption were completed,and elevated the concentrations of SCFA(acetate,propionate,and butyrate)in the cecal content on d 21(P<0.01).In conclusion,dietary DL-HMTBA supplementation improved the intestinal barrier function,immune homeostasis and optimized the microbiota to promote intestinal health status in broiler chickens.

Synthesis and characterization of superhydrophobic magnesium oxysulfate whiskers

Superhydrophobic materials have attracted much attention for their special wettability.In this study.magnesium oxysulfate(MOS)whiskers were surface modified by vinyltrimethoxysilane(VTMS)and prepared as superhydrophobic materials,which are expected to be widely used in self-cleaning,corro-sion prevention,and oil-water separation.The factors of silane concentration,hydrolysis time,reaction temperature,and reaction time were investigated.The superhydrophobic Mos whiskers were synthe-sized.SEM and XRD turned out that there were no apparent changes in the morphology and crystalli-zation behavior of whiskers before and after modification,while the surface was uniformly coated with a layer of non-crystal material,and the surface of the whiskers employed a chemical bond Si-O-Mg covalently connected.The thermogravimetric analysis ultimately demonstrated that surface modification was beneficial to the improvement of the thermal stability of MoS whiskers.Superhydrophobic MoS whiskers showed good compatibility with organic solvents through oil-water separation experiments,and demonstrated excellent self-cleaning performance.The methodology for the surface treatment of Mos whiskers to prepare superhydrophobic whiskers in this work may be extended for other whiskers or fillers,which may be promising for the preparation of superhydrophobic materials.

离子液体[CnPy][HSO4]（n=2,3,4,5,6）的溶解焓研究

离子液体被称为21世纪环境友好溶剂,目前已成为多学科交叉的、最活跃的前沿研究课题之一。离子液体热力学数据是离子液体工业化的重要参数,也是工艺设计的依据,但是这些基础数据的缺乏,已限制了离子液体工业化的应用。为此,本文选择5种酸性离子液体N-烷基吡啶硫酸氢盐[CnPy][HSO4](n=2, 3, 4, 5, 6)为研究对象,首先进行合成并利用核磁共振氢谱(1H NMR)对其结构进行表征。然后,利用标准物质KCl标定过的SRC100型量热计,测定5种酸性离子液体[CnPy][HSO4](n=2, 3, 4, 5, 6)在不同浓度的的溶解焓,将测定的数据进行Pitzer方程拟合,得到了5种离子液体[CnPy][HSO4](n=2, 3, 4, 5, 6)的无限稀释摩尔溶解热和相应的Pitzer参数。

Arginine promotes myogenic differentiation and myotube formation through the elevation of cytoplasmic calcium concentration

This study aimed to explore the mechanism underlying arginine-promoted myogenesis of myoblasts.C2C12 cells were cultured with a medium containing 0.1,0.4,0.8,or 1.2 mmol/L arginine,respectively.Cell proliferation,viability,differentiation indexes,cytoplasmic Ca^(2+)concentration,and relative mRNA expression levels of myogenic regulatory factors(MRF)and key Ca2+channels were measured in the absence or presence of 2 chemical inhibitors,dantrolene(DAN,10μmol/L)and nisoldipine(NIS,10μmol/L),respectively.Results demonstrated that arginine promoted myogenic differentiation and myotube formation.Compared with the control(0.4 mmol/L arginine),1.2 mmol/L arginine upregulated the relative mRNA expression levels of myogenin(MyoG)and Myomaker at d 2 during myogenic induction(P<0.05).Cytoplasmic Ca^(2+)concentrations were significantly elevated by arginine supplementation at d 2 and 4(P<0.05).Relative mRNA expression levels of Ca^(2+)channels including the type 1 ryanodine recepto r(RyR1)and voltage-gated Ca^(2+)channel(Cav1.1)were upregulated by 1.2 mmol/L arginine during2-d myogenic induction(P<0.01).However,arginine-promoted myogenic potential of myoblasts was remarkably compromised by DAN and NIS,respectively(P<0.05).These findings evidenced that the supplementation of arginine promoted myogenic differentiation and myotube formation through increasing cytoplasmic Ca^(2+)concentration from both extracellular and sarcoplasmic reticulum Ca^(2+).

On f-Hypercentral Actions of Finite Group

Let f be a formation function and G an A-group.It is said that A acts f-hypercentrally on G if A acts f-centrally on every A-composition factor of G.In this paper,groups are investigated by f-hypercentral actions.In particular,some well-known results,including a theorem of Huppert and a theorem of Hall-Higman,are generalized.

p53 coordinates with △133p53 isoform to promote cell survival under low-level oxidative stress

Dear Editor,Reactive oxygen species(ROS)can serve as intracellular signals that promote cell proliferation and survival at sub-toxic levels,or function as toxic substances that cause cell death and senescence at high levels(Weinberg and Chandel,2009).p53 plays a key role in the control of cellular response to ROS by upregulating the expression of either antioxidant genes under low level of oxidative stresses or pro-oxidative and apoptotic genes under high level of stresses(Vigneron and Vousden,2010;Hafsi and Hainaut,2011).However,how p53 differentially regulates gene expression in response to different ROS level remains elusive.△133p53 is an N-terminal truncated form of p53(Bourdon et al.,2005)and functions to antagonize p53 apoptotic activity and to promote DNA double-strand break repair(Chen et al.,2009;Aoubala et al.,2011;Gong et al.,2015).In this study,we investigated the functional interaction between p53 and △133p53 in response to various levels of ROS.

Nanoconfining Cation-π Interactions as a Modular Strategy to Construct Injectable Self-Healing Hydrogel

Cation-πinteraction is considered one of the strongest noncovalent interactions in aqueous solutions,which endows natural biomolecules(e.g.,proteins)with robust wet adhesion and cohesion in humid/underwater environments.However,it remains a challenge to construct synthetic functional materials(e.g.,self-healing hydrogels)by adopting the cation-πinteractions rationally.Herein,we present a facile and novel strategy to fabricate injectable self-healing synthetic hydrogel from self-assembly of a thermoresponsive ABA triblock copolymer via cation-πinteractions.