Significance of dormant forms of Helicobacter pylori in ulcerogenesis

Nearly half of the global population are carriers of Helicobacter pylori(H. pylori),a Gram-negative bacterium that persists in the healthy human stomach. H. pylori can be a pathogen and causes development of peptic ulcer disease in a certain state of the macroorganism. It is well established that H. pylori infection is the main cause of chronic gastritis and peptic ulcer disease(PUD). Decontamination of the gastric mucosa with various antibiotics leads to H. pylori elimination and longer remission in this disease. However,the reasons for repeated detection of H. pylori in recurrent PUD after its successful eradication remain unclear. The reason for the redetection of H. pylori in recurrent PUD can be either reinfection or ineffective anti-Helicobacter therapy. The administration of antibacterial drugs can lead not only to the emergence of resistant strains of microorganisms,but also contribute to the conversion of H. pylori into the resting(dormant) state. The dormant forms of H. pylori have been shown to play a potential role in the development of relapses of PUD. The paper discusses morphological H. pylori forms,such as S-shaped,C-shaped,U-shaped,and coccoid ones. The authors proposes the classification of H. pylori according to its morphological forms and viability.

Projecting Wintertime Newly Formed Arctic Sea Ice through Weighting CMIP6 Model Performance and Independence

Precipitous Arctic sea-ice decline and the corresponding increase in Arctic open-water areas in summer months give more space for sea-ice growth in the subsequent cold seasons. Compared to the decline of the entire Arctic multiyear sea ice,changes in newly formed sea ice indicate more thermodynamic and dynamic information on Arctic atmosphere–ocean–ice interaction and northern mid–high latitude atmospheric teleconnections. Here, we use a large multimodel ensemble from phase 6 of the Coupled Model Intercomparison Project(CMIP6) to investigate future changes in wintertime newly formed Arctic sea ice. The commonly used model-democracy approach that gives equal weight to each model essentially assumes that all models are independent and equally plausible, which contradicts with the fact that there are large interdependencies in the ensemble and discrepancies in models' performances in reproducing observations. Therefore, instead of using the arithmetic mean of well-performing models or all available models for projections like in previous studies, we employ a newly developed model weighting scheme that weights all models in the ensemble with consideration of their performance and independence to provide more reliable projections. Model democracy leads to evident bias and large intermodel spread in CMIP6 projections of newly formed Arctic sea ice. However, we show that both the bias and the intermodel spread can be effectively reduced by the weighting scheme. Projections from the weighted models indicate that wintertime newly formed Arctic sea ice is likely to increase dramatically until the middle of this century regardless of the emissions scenario.Thereafter, it may decrease(or remain stable) if the Arctic warming crosses a threshold(or is extensively constrained).

Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the workpiece.This technology has a very broad application prospect in industrial manufactur-ing.Researchers have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this field.In this review,metals were classified according to their crystal structures.The effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were reviewed.The main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

Study on Effectiveness of Solitary-Wave-Like Form Based on Overtopping Data from Irregular Wave Tests

The previous study conducted by Li(2022)demonstrates that the Goda graph can be adequately represented by a solitary-wave-like form across the entire range of relative water depth,with the exception of the extremely shallow zone.However,it remains uncertain whether this form is equally effective when applied to test data generated by irregular waves,as the Goda graph was initially developed based on overtopping data from regular wave tests.Additionally,it is unclear whether this form is suitable for formulating overtopping discharge at composite vertical walls.In order to address these questions,a 2D overtopping experiment was conducted,incorporating both simple and composite types of vertical walls,with various relative water depths across the entire range,excluding the extremely shallow zone.A novel analysis procedure was developed,which proved to be highly productive and can be considered a general method for data fitting.Ultimately,the study yielded two conclusions:(1)the solitary-wave-like form is remarkably effective in formulating overtopping test data generated by irregular waves,regardless of whether the vertical wall is simple or composite,and(2)the resulting formulas exhibit definitely better performance compared with existing formulas.

Deformation mechanisms and microstructural characteristics of AZ61 magnesium alloys processed by a continuous expansion extrusion approach

The unique continuous extrusion-based severe plastic deformation approaches were proposed recently to process high-performance magnesium (Mg) alloys,while the in-depth deformation mechanisms under such complicated thermomechanical conditions were not well understood In the present work,the fundamental deformation behaviors of AZ61 Mg alloy from 25 to 400°C were firstly examined under uniaxial compression deformation.Then the deformation mechanisms and microstructural characteristics of AZ61 Mg alloy during continuous expansion extrusion forming (CEEF) were systematically investigated by microstructural observations,finite element and cellular automata simulations The results showed that the continuous evolutions of temperature,larger strain level and complex stress state with strain rate range of 0~5.98 s-1during CEEF brought the distinctive dynamic recrystallization behaviors and texture development in AZ61 Mg alloy,which were different to that of uniaxial compression deformation.In details,a remarkable grain refinement was achieved via CEEF processing due to the simultaneous actions of continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX).Gradually enhanced CDRX were observed from center to edge region,which had significant effects on the texture distribution and texture strength.The c-axis of most grains rotated under distinctive shear strain following parabolic metal flow,resulting in stable fiber texture.In addition,the evolution of the internal texture of the alloy led to an obvious increase in the Schmid factor for the activation of basal(c+a)slip system.©2022 Chongqing University.Publishing services provided by Elsevier B.V.on behalf of Ke Ai Communications Co.Ltd.

基于WinForm窗体的光谱扫描系统设计

目前,国内市场上广泛使用的紫外–可见分光光度计、紫外–荧光分光光度计大部分不具备自动波长扫描功能,只能人工操作和读数,因此使用受到了极大的限制。本文设计了一款基于Visual C#WinForm窗体的光谱仪软件,通过串口接收紫外–可见分光光度计、紫外–荧光分光光度计等光谱仪器的检测数据,并在电脑端对数据进行处理后,可以自动计算出吸光度、透光率、荧光强度等光谱参数,直观地显示波长扫描光谱图。

Forming and Springback Prediction of Strips Under Multi-square Punch Concave Forming Process Considering Partial-unloading Effects

To further investigate the forming mechanism and springback characteristics of strips under multi-square punch forming (MSPF) considering partial-unloading effects, a series of concave form ing tests of strips are conducted on the MSPF machine. This paper aims to reveal the physical mecha nism of the elastic-plastic deformation in the MSPF process considering the effect of the forming ap proaches, and derive appropriate mathematical interpretations. The theoretical model is firstly estab lished to analyse the concave forming mechanism and springback characteristics of the strip, and its accuracy is then validated by experimental data. The forming history and load evolutions are depicted to explore the required forming capacity through the proposed analytical method. Besides, the paramet ric studies are carried out to discuss their effects on the springback of the strip. The results suggest that the deformation paths of the strip are influenced by the forming approach, and the springback of the strip in convex forming is larger than that in concave forming.

In situ formation of an intimate solid-solid interface by reaction between MgH_(2) and Ti to stabilize metal hydride anode with high active material content

MgH_(2) and TiH_(2) have been extensively studied as potential anode materials due to their high theoretical specific capacities of 2036 and 1024 mAh/g,respectively.However,the large volume changes that these compounds undergo during cycling affects their performance and limits practical applications.The present work demonstrates a novel approach to limiting the volume changes of active materials.This effect is based on mechanical support from an intimate interface generated in situ via the reaction between MgH_(2) and Ti within the electrode prior to lithiation to form Mg and TiH_(2).The resulting Mg can be transformed back to MgH_(2) by reaction with LiH during delithiation.In addition,the TiH_(2) improves the reaction kinetics of MgH_(2) and enhances electrochemical performance.The intimate interface produced in this manner is found to improve the electrochemical properties of a MgH_(2)-Ti-LiH electrode.An exceptional reversible capacity of 800 mAh/g is observed even after 200 cycles with a high current density of 1 mA/cm^(2) and a high proportion of active material(90 wt.%)at an operation temperature of 120℃.This study therefore showcases a new means of improving the performance of electrodes by limiting the volume changes of active materials.

Assessment of the Drafting Quality of Request Forms Submitted to the Malaria and Parasitology Units at the Institut Pasteur de Cote d’Ivoire

Biological tests provide information on the medical analysis requested by both the patient and the prescriber. It is a communication link between the prescriber and the laboratory staff. The lack of some information on request forms not only affects the drafting quality of the test and patient care, but could also make thousands of data produced by healthcare centers unusable. The aim of this study was to assess the drafting quality of request forms submitted to the Malaria and Parasitology Units at the Institut Pasteur de Côte d’Ivoire. Methods: It was a descriptive cross-sectional study to assess the drafting quality of request forms of various prescribers received at the Institut Pasteur de Côte d’Ivoire. This study was conducted at the Malaria and Parasitology Units, department of Parasitology and Mycology (Institut Pasteur de Côte d’Ivoire), from 6th December 2020 to 6th December 2021. The information on each request forms was recorded on a data collection form designed for this purpose. Each data collection form corresponds to a request forms and each test to a patient. Results: Out of a total of 1990 request forms received, the patient’s age and sex were missing on 18% and 26.8% of the tests respectively. More than half (51.80%) of request forms did not indicate the patient’s place of residence. Clinical information was not provided on 45.90% of the tests. Prescribers omitting their signatures were 51%, stamps were 50.3% and contacts were 71.2%. Only 5.4% of request forms were of good drafting quality. Providing all the required information on the forms could facilitate the use and analysis of data and samples.

Analysis and synchronization controller design of dual-port gridforming voltage-source converters for different operation modes

Grid-tie voltage source converters(VSCs)can operate in three distinct modes:AC-dominant,DC-dominant,and balanced,depending on the placement of the stiff voltage sources.The distinct operation modes of the VSCs traditionally demand different synchronization control techniques,leading to heterogeneous VSCs.It is challenging for the power system to accommodate and coordinate heterogeneous VSCs.A promising universal synchronization control technique for VSCs is the DC-link voltage synchronization control(DVSC)based on a lead compensator(LC).The LC DVSC stabilizes both the DC and AC voltages of a VSC while achieving synchronization with the AC grid.This results in a dual-port grid-forming(DGFM)characteristic for the VSC.However,there has been very limited study on the stability and synchronization controller design of the VSCs with the LC DVSC operating in various modes.To bridge this gap,the paper presents a quantitative analysis on the stability and steady-state performance of the LC DVSC in all three operation modes of the DGFM VSC.Based on the analysis,the paper provides step-by-step design guidelines for the LC DVSC.Furthermore,the paper uncovers an instability issue related to the LC DVSC when the DGFM VSC operates in the balanced mode.To tackle the instability issue,a virtual resistance control is proposed and integrated with the LC DVSC.Simulation results validate the analysis and demonstrate the effectiveness of the DGFM VSC with the LC DVSC designed using the proposed guidelines in all three operation modes.Overall,the paper demonstrates the feasibility of employing the DGFM VSC with the LC DVSC for all three possible operation modes,which can help overcome the challenges associated with accommodating and coordinating heterogeneous VSCs in the power system.

Address forms in Chinese and English-speaking culture

Address form is one of markers of politeness and is an indispensable part of communication. An appropriate address form promotes interpersonal communication smoothly. An address form is polite in one culture, but might be inappropriate in another culture. The paper contrasts address forms in English and Chinese culture and exolores the reasons for their different choice of address terms.

Multi-Point Forming Technology for Sheet Metal

Multi-point forming (MPF) is an advanced manufacturing technology for three-dimensional sheet metal parts. In this paper, the MPF integrated system is described that can form a variety of part shapes without the need for solid dies, and given only geometry and material information about the desired part. The central component of this system is a pair of matrices of punches, and the desired discrete die surface is constructed by changing the positions of punches though the CAD and control system. The basic MPF process is introduced and the typical application examples show the applicability of the MPF technology. Wrinkle and dimple are the major forming defects in MPF process, numerical simulation is a feasible way to predict forming defects in MPF. In conventional stamping, the mode to form sheet metal with blankholder is an effective way to suppress wrinkling; the same is true in MPF. A MPF press with flexible blankholder was developed, and the forming results indicated the forming stability of this technique. Based on the flexibility of MPF, varying deformation path MPF and sectional MPF were explored that cannot be realized in conventional stamping. By controlling each punch in real-time, a sheet part can be manufactured along a specific forming path. When the path of deformation in MPF is designed properly, forming defects will be avoided completely and lager deformation is achieved. A work piece can be formed section by section though the sectional MPF, and this technique makes it possible to manufacture large size parts in a small MPF press. Some critical experiments were performed that confirmed the validity of two special MPF techniques.

NC INCREMENTAL SHEET METAL FORMING PROCESS AND VERTICAL WALL SQUARE BOX FORMING

The forming principle and deformation analysis of NC incremental sheet metalforming process as well as the process planning, experiment and key process parameters of verticalwall square box forming are presented. Because the deformation of sheet metal only occurs around thetool head and the deformed region is subjected to stretch deformation, the deformed region of sheetmetal thins, and surface area increases. Sheet metal forming stepwise is to lead to the whole sheetmetal deformation. The forming half-apex angle 9 and corner radius R are the main processparameters in NC incremental forming of vertical wall square box. According to sine law, a verticalwall square box can't be formed by NC incremental sheet metal forming process in a single process,rather, it must be formed in multi processes. Thus, the parallel line type tool path process methodis presented to form the vertical wall square box, and the experiment and analysis are made toverify it.

基于AutoForm的Z向拉延筋截面参数理论求解

为解决AutoForm拉延筋截面参数在3D软件设计中无法直接使用的问题,推算了在3D软件中可以直接使用的Z向拉延筋截面参数求解公式,主要有流入、流出侧Z向立面与拉延筋中心线的距离、凸筋圆角、凹筋圆角。使用CATIA软件设计的拉延筋与AutoForm自动生成的拉延筋进行模拟对比,得到了理想的验证结果,其中筋宽误差和筋高误差均控制在小于0.05 mm,拉延流入量误差控制在小于1 mm。

ELLIPTIC EQUATIONS IN DIVERGENCE FORM WITH DISCONTINUOUS COEFFICIENTS IN DOMAINS WITH CORNERS

We study equations in divergence form with piecewise Cαcoefficients.The domains contain corners and the discontinuity surfaces are attached to the edges of the corners.We obtain piecewise C^(1,α) estimates across the discontinuity surfaces and provide an example to illustrate the issue regarding the regularity at the corners.

Approach Based on Response-Surface Method to Optimize Lining of Dies Used in 3D Free-Bending Forming Technology

In three-dimensional free-bending forming(3D-FBF),the tube is not overly constrained,and the plastic deformation behavior and forming quality of the bent tube are significantly affected by the critical structure of the forming die lining.However,the effects of die-lining structural parameters on the tube quality,and a method to determine the combination of die-lining structural parameters is yet to be devised.This study aims to propose a new framework that allows one to understand the effects of various die-lining structural parameters on tube quality and to propose the best combination of die-lining structural parameters.First,finite-element modeling is performed to simulate 3D-FBF and examine the effects of individual die-lining structures on the quality of tube formation.The simulation results show that the deformation-zone length and die gap are positively correlated with the tube-section distortion and wall-thickness variation,whereas it shows an opposite trend with respect to the bending radius.Additionally,the lining chamfer radius of the bending die and the guide lining chamfer radius minimally affect the tube forming quality.Subsequently,the optimal die-lining structure is obtained using the response-surface method.The tube cross-sectional distortion rate reduced from 2.73 to 2.53%after the die lining is optimized.Additionally,the average inner-wall thickness reduced to 1.06 mm,whereas the average outer-wall thickness increased to 0.97 mm.This paper proposes a method for optimizing the forming-die-lining mechanism and for improving the tube forming quality in 3D-FBF.

Schur Forms and Normal-Nilpotent Decompositions

Real and complex Schur forms have been receiving increasing attention from the fluid mechanics community recently,especially related to vortices and turbulence.Several decompositions of the velocity gradient tensor,such as the triple decomposition of motion(TDM)and normal-nilpotent decomposition(NND),have been proposed to analyze the local motions of fluid elements.However,due to the existence of different types and non-uniqueness of Schur forms,as well as various possible definitions of NNDs,confusion has spread widely and is harming the research.This work aims to clean up this confusion.To this end,the complex and real Schur forms are derived constructively from the very basics,with special consideration for their non-uniqueness.Conditions of uniqueness are proposed.After a general discussion of normality and nilpotency,a complex NND and several real NNDs as well as normal-nonnormal decompositions are constructed,with a brief comparison of complex and real decompositions.Based on that,several confusing points are clarified,such as the distinction between NND and TDM,and the intrinsic gap between complex and real NNDs.Besides,the author proposes to extend the real block Schur form and its corresponding NNDs for the complex eigenvalue case to the real eigenvalue case.But their justification is left to further investigations.

Bioaccumulation,subcellular distribution and chemical forms of cadmium in Aster subulatus Michx.

【Objective】Through analyzing the bioaccumulation capacity,subcellular distribution and chemical forms of cadmium(Cd)in Aster subulatus Michx.,this study was to provide reference for revealing the Cd tolerance mechanism of A.subulatus Michx.【Method】After cultured for 24 d under the action of Hoagland nutrient solution and gradient Cd concentrations(0,30,60 and 90 mg/L),A.subulatus Michx.were harvested,and its leaf,stem and root were treated by differential centrifugation,chemical reagent extraction,and digested with graphite digester,respectively,then the Cd content in the root,stem and leaf were determined by atomic absorption spectroscopy.【Result】The experimental results indicated that the bioaccumulation capacity of Cd in A.subulatus Michx.was root>stem>leaf,and the maximum Cd concentration in the root,stem and leaf of A.subulatus Michx.were 130.74,78.69 and 56.62 mg/kg(fresh matter),respectively.Most of Cd stored in the cell wall and the soluble fractions of the root and leaf of A.subulatus Michx.,with only a smaller portion Cd in organelle fraction.Analysis result of subcellular Cd content showed that 52.27%-58.61%of Cd for root was mainly stored in the soluble fraction,but 42.10%-63.28%of Cd for leaf was mainly stored in the cell wall fraction.The concentration of pectates and protein integrated-Cd was higher in the root and leaf compared to other chemical forms Cd.Pectates and protein integrated-Cd was the main chemical forms Cd in the root and leaf of A.subulatus Michx.,and their percentages were 68.91%-74.80%and 57.38%-83.80%,respectively.Cd treatment could significantly increase the proportion of water-soluble organic acid Cd from 13.64%to 22.72%in root and undissolved phosphate Cd from 10.02%to 32.78%in leaf with increasing Cd concentration in the culture medium.【Conclusion】The root,stem and leaf of A.subulatus Michx.has strong bioaccumulation capacity to Cd,Cd is primarily stored in the soluble fractions of the root and cell wall fractions of the leaf,and less toxic pectates and protein integrated-Cd is the main chemical forms Cd in the root and leaf of A.subulatus Michx.,this might be the main mechanism of Cd tolerance in A.subulatus Michx.

MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation

In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 microns.Achieving such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously developed.To mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP directive.This helps ensure proper synchronization and avoid conflicts during parallel execution.Additionally,in the MPI implementation,the coins are partitioned into the desired number of regions.This division allows for efficient distribution of computational tasks across multiple processes.Numerical simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel efficiency.The results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental observations.Additionally,speedup ratio and parallel efficiency are assessed for the coining process simulation.The pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming model.This approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns.

Modeling monocular form deprivation in rabbits using a simulated-cataract intraocular lens

AIM:To establish an animal model of form deprivation amblyopia based on a simulated cataract intraocular lens(IOLs).METHODS:Poly(dimethyl siloxane)-SiO_(2) thin films(PSF)with different degrees of opacity as IOL materials were prepared.The light transmission of the PSF-IOL was measured,and its in vitro biosafety was determined by cell counting kit(CCK)-8 assay using the HLEC-B3 cell line and ARPE-19 cell line.Subsequently,the in vivo safety was determined by implanting the PSF-IOL with 10%wt SiO_(2) into the right eyes of New Zealand white rabbits(PSF-IOL group),and compared with two control groups:contralateral comparison group and normal control(NC)group(Contralateral comparison group:the fellow eye;NC group:a group of binocular normal rabbits without intervention).The flash visual-evoked potentials(F-VEPs)were measured to verify amblyopia.RESULTS:PSFs containing 0,2%,and 10%wt SiO_(2) were successfully constructed.The 0 SiO_(2) PSF was transparent,while the 10%wt SiO_(2) PSF was completely opaque.It was found that PSF did not induce unwanted cytotoxicity in HLECs and ARPE19 cells in vitro.In vitro,PSF-IOL with 10%wt SiO_(2) was also non-toxic,and no significant inflammation or structural changes occurred after four weeks of PSF-IOL implantation.Finally,our IOL-simulated congenital cataract rabbit detected by F-VEPs suggested tentative amblyopia.CONCLUSION:A PSF-IOL that mimics cataracts is created.A novel form deprivation model is created by the IOL-simulated congenital cataract rabbit.It can be developed fast and stable and holds great potential for future study.