Collision-free Scheduling of Multi-bridge Machining Systems： A Colored Traveling Salesman Problem-based Approach

Multi-bridge machining systems(MBMS) have gained wide applications in industry due to their high production capacity and efficiency. They contain multiple bridge machines working in parallel within their partially overlapping workspaces.Their scheduling problems can be abstracted into a serial-colored travelling salesman problem in which each salesman has some exclusive cities and some cities shared with its neighbor(s). To solve it, we develop a greedy algorithm that selects a neighboring city satisfying proximity. The algorithm allows a salesman to select randomly its shared cities and runs accordingly many times. It can thus be used to solve job scheduling problems for MBMS. Subsequently, a collision-free scheduling method is proposed to address both job scheduling and collision resolution issues of MBMS. It is an extension of the greedy algorithm by introducing time window constraints and a collision resolution mechanism. Thus, the augmented greedy algorithm can try its best to select stepwise a job for an individual machine such that no time overlaps exist between it and the job sequence of the neighboring machine dealt in the corresponding overlapping workspace; and remove such a time overlap only when it is inevitable. Finally, we conduct a case study of a large triplebridge waterjet cutting system by applying the proposed method.

Data-Driven Discovery of Stochastic Differential Equations

Stochastic differential equations(SDEs)are mathematical models that are widely used to describe complex processes or phenomena perturbed by random noise from different sources.The identification of SDEs governing a system is often a challenge because of the inherent strong stochasticity of data and the complexity of the system’s dynamics.The practical utility of existing parametric approaches for identifying SDEs is usually limited by insufficient data resources.This study presents a novel framework for identifying SDEs by leveraging the sparse Bayesian learning(SBL)technique to search for a parsimonious,yet physically necessary representation from the space of candidate basis functions.More importantly,we use the analytical tractability of SBL to develop an efficient way to formulate the linear regression problem for the discovery of SDEs that requires considerably less time-series data.The effectiveness of the proposed framework is demonstrated using real data on stock and oil prices,bearing variation,and wind speed,as well as simulated data on well-known stochastic dynamical systems,including the generalized Wiener process and Langevin equation.This framework aims to assist specialists in extracting stochastic mathematical models from random phenomena in the natural sciences,economics,and engineering fields for analysis,prediction,and decision making.

Value of the controlling nutritional status score and psoas muscle thickness per height in predicting prognosis in liver transplantation

BACKGROUND Patients with end-stage liver disease usually have varying degrees of malnutrition,and severe malnutrition may affect the prognosis of patients after liver transplantation(LT).However,there is no recommended standard for the nutrition assessment of patients waiting for LT,and it is unknown whether malnutrition has an impact on the occurrence of postoperative complications.AIM The study aim was to investigate the value of the controlling nutritional status(CONUT)score and psoas muscle thickness per height(PMTH)in predicting prognosis in LT.METHODS We retrospectively analyzed the clinical data of 313 patients who underwent classic orthotopic LT from January 2016 to December 2018 in Tianjin First Central Hospital affiliated with Tianjin Medical University.The CONUT score is derived from the preoperative serum albumin and total cholesterol levels,and total lymphocyte count.Patients were divided into low(≤4),medium(5–8),and high(9–12)CONUT score groups perioperative characteristics,Clavien-Dindo grade III/IV/V postoperative complications,graft loss and infection,and cumulative postoperative survival in the three groups were compared 3 mo after LT.PMTH was calculated as the ratio of the transverse thickness of the psoas muscle in the umbilical plane to the height of the patient.The cutoff values of receiver operating characteristic curves were determined separately for men and women.The values were 14.1 cm/m2 for women and 17.9 cm/m2 for men.The patients were then divided into low and high PMTH groups by the cutoff values.The comparison of data between the two groups was the same as above.RESULTS Patients with medium and high CONUT scores had lower preoperative serum hemoglobin,more intraoperative red blood cell(RBC)transfusions,longer postoperative intensive care unit stay and hospital stays,higher 7 and 14 preoperative-day serum bilirubin levels,and a higher incidence of postoperative grade III/IV complications and infections than patients with low CONUT scores.Differences in the 3-mo cumulative survival among the three groups were not significant.Patients with a low PMTH had higher preoperative serum urea nitrogen,more intraoperative packed RBC and frozen plasma transfusions,longer times to postoperative ventilator extubation,higher incidence of total postoperative complications,and a lower 3-mo cumulative survival than those with a high PMTH.CONCLUSION A CONUT score≥5 and a low PMTH were both associated with poor prognosis in LT.The CONUT score had no predictive value for short-term patient survival after LT,but the PMTH was predictive of short-term patient survival after LT.

Effects of immunoglobulin D on expression of IgD receptor and protein tyrosine kinase signaling in human CD4^+ T cells

OBJECTIVE To observe whether human CD4^+T cells could be activated by immuno-globulin D(IgD) via IgD receptor(IgDR)-Lck.METHODS Human CD4^+T cells were purified from peripheral blood mononuclear cells(PBMCs) with microbeads.The viability of T cells were detected by CCK-8.The binding affinity and expression of IgDR on T cells were detected by flow cytometry.The protein expression of IgDR,Lck and P-Lck were analyzed by western blot.RESULTS IgD could concentration-dependent bind to IgDR on CD4^+T cells.The expression of IgDR was increased in response to treatment with IgD in a time-dependent and concentration-dependent manner.Stimulating by IgD resulted in enhanced phosphorylation of Lck compared with that in the medium control sample.The expression of Lck was not changed.As inhibitor of PTK,Herbimycin A or A770041,which combined with IgD could significantly inhibit phosphorylation of Lck(Tyr^(394)).The proliferation promoting effect of IgD was blocked by Herbimycin A or A770041.IgD could stimulate CD4^+T cell activation and proliferation through upregulating activating tyrosine residue of Lck(Tyr^(394)) phosphorylation.CONCLUSION These results demonstrate that IgD exaggerates CD4^+T cell activities,which may be through promoting Lck phosphorylation.

Flexible interdigitated layered framework with multiple accessible active sites for high-performance CH_(3)I capture

The development of adsorbent materials for effective capture of radioactive iodomethane(CH_(3)I) from the off-gas of used nuclear fuel reprocessing, remains a significant and challenging line of research because currently state-of-art adsorbents still suffer from low binding affinity with CH_(3)I. Here, we proposed a brand-new adsorption topological structure by developing a 2D interdigitated layered framework, named SCU-20, featuring slide-like channel with multiple active sites for CH_(3)I capture. The responsive rotating-adaptive aperture of SCU-20 enables the optimal utilization of all active sites within the pore for highly selective recognition and capture of CH_(3)I. A record-breaking CH_(3)I uptake capacity of 1.84 g/g was achieved under static sorption conditions with saturated CH_(3)I vapor. Both experimental and theoretical findings demonstrated that the exceptional uptake of SCU-20 towards CH_(3)I can be attributed to the confined physical electrostatic adsorption of F sites, coupled with the chemical nitrogen methylation reaction with uncoordinated N atoms of pyrazine. Moreover, dynamic CH_(3)I uptake capacity potentially allows for the capture of CH_(3)I in simulated real-world off gas reprocessing conditions. This study highlights the potential of SCU-20 as a promising candidate for efficient capture of iodine species and contributes to the development of effective solutions for radioactive iodine remediation.

Synergy of first-and second-sphere interactions in a covalent organic framework boosts highly selective platinum uptake

Platinum recovery from waste electrical and electronic equipment(WEEE) in highly acidic solutions is significant to the electronics industry and environmental remediation. However, the lack of ingenious design and synergetic coordination gives rise to unsatisfied PtCl_(4)^(2-)extraction capacities and selectivities in most previously reported adsorbents(e.g., polymeric and inorganic materials). Herein, we proposed a synergistic strategy that realizes highly selective PtCl_(4)^(2-)uptake through first-and second-sphere coordinations. The proof-of-concept imine-linked covalent organic framework(SCU-COF-3) was found to chelate Pt Cl42-via the direct N…Pt coordination and the synergistically interlaminar N–H…Cl hydrogen bonds, which was disclosed by the comprehensive analysis of extended X-ray adsorption fine structure(EXAFS) characterizations and density functional theory(DFT) calculations. The unique adsorption mechanism imparts a superior adsorption capacity(168.4 mg g-1)and extraordinary Pt(II) selectivity to SCU-COF-3 under static conditions. In addition, SCU-COF-3 exhibits an upgraded distribution coefficient of 1.62 × 10^(5)mL· g^(-1), one order of magnitude higher than those of reported natural adsorbents. Specifically, SCU-COF-3 can extract PtCl_(4)^(2- )quantitatively from a simulated acidic waste solution coexisting with other 12 competitive ions, suggesting its promising application in practical scenarios.

The Leu477 and Leu613 of ORF2-Encoded Protein Are Critical in Forming Neutralization Antigenic Epitope of Hepatitis E Virus Genotype 4

Hepatitis E virus （HEV） genotype 4 was originally identified in China. Its neutralization antigenic epitopes have not been characterized. Recently, we identified a neutralizing monoclonal antibody （mAb） IG10, which was generated following immunization of mice with p166Chn, a recombinant protein comprising 464-629 amino acids （aa） of the HEV genotype 4 capsid protein. In this study, a panel of 22 N- and/or C-terminal truncated and 6 site-directed mutated p166Chn proteins were prepared. Only those N- or C-terminal truncated proteins containing the region 477-613 aa could react with the mAb 1G10, suggesting the neutralization epitope of HEV genotype 4 is located between aa477 and aa613. However, a both N- and C-terminal truncated protein, pN477-C613, neither reacted to 1G10 nor elicited neutralizing antibodies in mice, while another both terminal truncated protein, pN472-C617, did, suggesting the flanking regions of the pN477-C613 could help to stabilize and allow presentation of the neutralization epitope to the immune system. Substituting Leu477 and/or Leu613 with the polar, uncharged threonine （Thr） caused 〉 50% reduction of the mutants＇ immunoreactivity to IG10, whereas replacement by hydrophobic phenylalanine （Phe） made little impact on the immunoreactivity, revealing functional associations between hydrophobicity of aa at positions 477 and 613 and the antigenicity of p166Chn. These data suggested Leu477 and Leu613 are critical in forming the neutralization epitope of HEV genotype 4. Cellular ＆ Molecular Immunology. 2008;5（6）：447-456.

The effect of Bi composition on the electrical properties of InP1-xBix

Ⅲ-ⅤSemiconductors containing a small amount of Bi,known as dilute bismides,have attracted great interest in recent years,due to the large band-gap reduction and other unique properties[1,2].Previous studies have been primarily focused on the growth and optical properties of the GaAs-based bismuthides[3],while the properties of other dilute bismides are less well understood.Berding et al.[4]theoretically predicted that InPBi is expected to be

Chromate separation by selective crystallization

A new paradigm to remove toxic chromate anions from aqueous solution by crystallization of chromatewater clusters with imine-linked guanidinium cationic ligands is introduced.The guanidium-based cationic ligand was easily prepared through the imine condensation of an alde hyde and aminoguanidine hydrochloride.The cationic imine-linked guanidinium liga nd(BBIG-CI)showed a high re moval capacity(292.5 mg/g)in the solutions.Rapid decontamination of chromate anions from the wastewater by this cationic ligand was resulted from an instantaneous crystallization.The produced guanidium chromate salts have an extremely low solubility(Ksp,BBIG=8.19×10^9).Such superior removal performance of these mate rials was attributed to the cha rge-assisted hydrogen bonding between the cationic ligand and chromate-water hydrate anions,which was revealed by the single-crystal X-ray diffraction analysis and density functional theory(DFT)calculations.In addition,the succes s ful recove ry of the guanidium-based ligand makes it more attractive for real-world applications.