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The flow behavior of three-dimensional (3D) dendrite growth with random preferred angle under natural convection was studied by using the Lattice Boltzmann-Cellular Automata (LB-CA) method with dynamic and static grids. In this model, the temperature field, flow field and solute field calculated by Lattice Boltzmann method (LBM) and dendrite growth calculated by CA method were carried out in static and dynamic grids respectively, and the coupling between LBM and CA was performed by interpolation of calculation parameters between dynamic and static grids. Results show that the asymmetry of solid phase distribution makes the streamline distribution more complex. At the initial stage of multiple dendrites growth, the fluid flow is relatively free. When dendrites grow close to each other, the fluid flow is blocked and can only flow along the gap between dendrites. During the wall equiaxed-columnar-central equiaxed crystals transformation (ECET) process, dense eddy current is formed at the wall equiaxed crystals at first. Then, when the wall equiaxed crystals gradually develop into columnar crystals, the eddy current moves with the solid-liquid interface. When the central equiaxed crystals are formed, the eddy current at the front of the columnar crystals gradually disappears. New eddies appear as the central equiaxed crystal grows.

ObjectiveTo investigate the effect of honokiol on demyelination after compressed spinal cord injury (CSCI) and it's possible mechanism.DesignAnimal experiment study.SettingInstitute of Neuroscience of Chongqing Medical University.InterventionsTotal of 69 Sprague–Dawley (SD) rats were randomly divided into 3 groups: sham group (n=15), honokiol group (n=27) and vehicle group (n=27). After established CSCI model by a custom-made compressor successfully, the rats of sham group were subjected to the limited laminectomy without compression; the rats of honokiol group were subjected to CSCI surgery and intraperitoneal injection of 20 mg/kg honokiol; the rats of vehicle group were subjected to CSCI surgery and intraperitoneal injection of an equivalent volume of saline.Outcome measures:The locomotor function of each group was assessed using the Basso, Beattie and Bresnahan (BBB) rating scale. The pathological changes of myelinated nerve fibers of spinal cord in 3 groups were detected by osmic acid staining and transmission electron microcopy (TME). Immunofluorescence and Western blot were used to research the experessions of active caspase-3, caspase-12, cytochrome C and myelin basic protein (MBP) respectively.ResultsIn the vehicle group, the rats became paralyzed and spastic after injury, and the myelin sheath became swollen and broken down along with decreased number of myelinated nerve fibers. Western blot analysis manifested that active caspase-3, caspase-12 and cytochrome C began to increase 1 d after injury while the expression of MBP decreased gradually. After intervened with honokiol for 6 days, compared with the vehicle group, the locomotor function and the pathomorphological changes of myelin sheath of the CSCD rats were improved with obviously decreased expression of active caspase-3, caspase-12 and cytochrome C.ConclusionsHonokiol may improve locomotor function and protect neural myelin sheat from demyelination via prevention oligodendrocytes (OLs) apoptosis through mediate endoplasmic reticulum (ER)-mitochondria pathway after CSCI.

•We analyzed 1990–2019 GBD data on mortality and DALYs for diet-related gastrointestinal cancers among 15–49 year olds in 204 countries.•Colorectal cancer burden was greatest, followed by esophageal and stomach cancers.•Cancer burden correlated with higher SDI, except esophageal cancer inversely. Lower SDI regions had lowest DALY rates; higher SDI regions had higher rates.•Males had significantly higher DALY rates than females for colorectal, esophageal and stomach cancers.•In 2019, considerable global dietary cancer burden inequalities emerged among youth/young adults. Highest DALYs in Bulgaria; lowest in Oman.•Our analyses show a rising global burden, greatest impact in high-middle/high SDI regions. Targeted interventions worldwide are key to curb this trend.

Efficiently and accurately predicting the steering ability of the bottom hole assembly (BHA) in slide drilling is a crucial yet challenging task. While the industry standard three-point geometry method is computationally efficient, it cannot capture the intricate mechanics involved in the drilling process. Conversely, utilizing the whole drill string dynamics model for simulating slide drilling provides a more comprehensive representation but involves time-consuming evaluations, making it difficult to balance precision and efficiency. This study addresses this challenge by proposing a rapid evaluation method that ensures both speed and accuracy by developing a multi-body dynamics rapid model of the slide drilling system. Based on the whole drill string model, this method incorporates two key techniques to achieve its primary objective. Firstly, it utilizes the equivalent torque model of the bit, which includes the fixed joint and the virtual rotational velocity, to replace the original revolute joint between the positive displacement motor (PDM) and the bit. Secondly, a segmentation model is established to decouple the simulation of the BHA drilling process from the drill string equilibrium process, thereby significantly reducing the slide drilling system’s degree of freedom (DOF). The proposed method offers a new approach to improving the efficiency of evaluating the steering ability of the slide drilling system while ensuring a high level of accuracy.

Ergothioneine (EGT) represents valuable protective functions for humans, but EGT from the diet cannot meet daily requirements. Although the heterologous synthesis of EGT had been achieved, it is still a challenge to obtain stable and high-yield EGT-producing cell factories. Here, after the co-overexpression of the EGT synthetic gene cluster and hisG, hisC, and allB1in Mycolicibacterium neoaurum, the natural EGT titer was increased by 7.2-folds. However, the degradation problem of EGT in large-scale fermentation needs to be urgently solved. A putative lyase gene Mn_3042was inactivated, thus inhibiting the product degradation and increasing the EGT titer by 21%. Moreover, the enhancement of S-adenosyl- l-methionine regeneration further increased EGT titer by 28%. After optimization of fed-batch fermentation, the yield of EGT was boosted to 1.56?g/L with a productivity of 7.2?mg/L/h. This study provides a systematic engineering strategy for developing EGT-producing cell factories. M. neoaurumwas systematically engineered to produce ergothioneine.Regulating of a lyase and SAM regeneration boosted the production of ergothioneine.The engineered M. neoaurumrealized the production of 1.56?g/L ergothioneine. M. neoaurumwas systematically engineered to produce ergothioneine. Regulating of a lyase and SAM regeneration boosted the production of ergothioneine. The engineered M. neoaurumrealized the production of 1.56?g/L ergothioneine.

An asymmetric synthesis of silicon-stereogenic monohydrosilanes by rhodium-catalyzed dehydrogenative C–H silylation is developed. The process is suitable for the synthesis of various asymmetrically trisubstituted 1H-benzosiloles and 1H-benzosilolometallocenes in good yields with excellent chemo-, regio-, and stereocontrol. These selected silicon-stereogenic 1H-benzosilole compounds exhibit bright blue fluorescence and CPL (circular polarized luminescence) signals, which could be attractive to practitioners of materials science.

An efficient asymmetric halogenation of cyclic diaryliodonium salts is demonstrated, which gives access to a wide range of axially chiral 2,2′-dihalobiaryls in good to excellent yields and with excellent enantioselectivities. The use of CuX with chiral bisoxazoline ligand and tetrabutylammonium halides in the unique solvent of hexafluoroisopropanol (HFIP) led to the best results in the process. The axially chiral 2,2′-dihalobiaryls can be transformed into a number of enantiopure chiral ligands that could be potentially useful in asymmetric catalysis.

ABSTRACTRectal cancer is a life‑threatening disease worldwide. Chemotherapy resistance is common in rectal adenocarcinoma patients and has unfavorable survival outcomes; however, its related molecular mechanisms remain unknown. To identify genes related to the initiation and progression of rectal adenocarcinoma, three datasets were obtained from the Gene Expression Omnibus database. In total, differentially expressed genes were analyzed from 294 tumor and 277 para-carcinoma samples from patients with rectal cancer. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functions were investigated. Cytoscape software and MicroRNA Enrichment Turned Network were applied to construct a protein-protein interaction network of the dependent hub genes and related microRNAs. The Oncomine database was used to identify hub genes. Additionally, Gene Expression Profiling Interactive Analysis was applied to determine the RNA expression level. Tumor immune infiltration was assessed using the Tumor Immune Estimation Resource database. The expression profiles of hub genes between stages, and their prognostic value, were also evaluated. During this study, data from The Cancer Genome Atlas were utilized. In rectal adenocarcinoma, four hub genes including CXCL1, CXCL2, CXCL3, and GNG4 were highly expressed at the gene and RNA levels. The expression of CXCL1, CXCL2, and CXCL3 was regulated by has-miR-1-3p and had a strong positive correlation with macrophage and neutrophil. CXCL2 and CXCL3 were differentially expressed at different tumor stages. High expression levels of CXCL1 and CXCL3 predicted poor survival. In conclusion, the CXCL1 and CXCL3 genes may have potential for prognosis and molecular targeted therapy of rectal adenocarcinoma.

•RPL7L1 was found to be aberrantly overexpressed in multiple tumor types such as LIHC, LUAD, COAD, GBM, BRCA, HNSC based on analyses of TCGA and GTEx data. Its expression was higher in later tumor stages and lymphocyte cells.•High RPL7L1 expression correlated with poor prognosis for OS and DSS in cancers like LIHC, SARC, BRCA and HNSC. Low expression correlated with poor prognosis in LGG and KIRC.•Methylation plays a key role in RPL7L1 expression regulation. Hypermethylation correlated with poor prognosis in LIHC, KIRC, SARC, UCEC. Hypomethylation correlated with poor prognosis in HNSC and LUSC.•RPL7L1 was found to suppress anti-tumor immunity by increasing immunosuppressive cells like CAFs and MDSCs in cancers like LIHC, HNSC, BRCA. It negatively correlated with immune cells and stromal scores.•Single-cell analysis showed RPL7L1 was highly expressed in CRC, OV, TNBC and correlated negatively with inflammation, hypoxia, apoptosis markers.•RPL7L1 mutation frequency was higher in ESCA, STAD, OVSC and correlated with genes like IGLV3-1. It positively correlated with TMB, MSI, LOH especially in LIHC.•Higher RPL7L1 indicated greater chemoresistance in several cancers and predicted immunotherapy response better than TMB, B-clonality markers.•Functional experiments validated RPL7L1 promoted proliferation and migration of liver cancer cells and inhibited apoptosis.•In summary, RPL7L1 plays an oncogenic role in multiple cancers and could be a potential prognostic and predictive biomarker.

Exciton sizes influence transport processes and spectroscopic phenomena in molecular aggregates and crystals. Thermally driven nuclear motion generally localizes electronic states in equilibrium systems. Exciton sizes also undergo dynamic changes caused by nonequilibrium relaxation in the lattice structure local to the photoexcitations (i.e., self-trapping). The α-phase of crystalline perylene is particularly well-suited for fundamental studies of exciton self-trapping mechanisms. It is generally agreed that a subpicosecond self-trapping process in α-perylene localizes photoexcited excitons onto pairs of closely spaced molecules (i.e., dimers), which then relax through excimer emission. Here, electronic relaxation dynamics in α-perylene single crystals are investigated using a variety of nonlinear optical spectroscopies in conjunction with a Frenkel exciton model. Linear absorption and photon echo spectroscopies suggest that excitons are delocalized over less than four unit cells (16 molecules) at 78 K prior to self-trapping. Stimulated Raman spectroscopies conducted on and off electronic resonance reveal significant vibronic coupling in a mode at 104 cm−1, which corresponds to the displacement between perylene molecules comprising a dimer. Strong vibronic coupling in this mode suggests that motion along the interdimer axis is instrumental in driving the self-trapping process. The results are discussed in the context of our recent study of tetracene and rubrene single crystals in which similar experiments and models were employed.

ABSTRACTCutting parameter selection is significant for process planning which directly affects product quality, production efficiency and cost. However, most literature does not consider both the cost and the carbon emissions as optimisation objectives for process evaluation. This paper presents a method for cutting parameter selection by considering both cost and carbon emissions. First, a metric called profit per unit carbon emissions is proposed with consideration of the carbon emissions and processing cost. The relationships between cutting parameters，carbon emissions and processing cost are analysed. Second, an optimisation model for the parameters used in a turning process is built where the spindle speed, feed rate and cutting depth are taken into account as optimisation variables. Constraints are proposed based on machine parameters and processing quality requirements. A genetic algorithm (GA) is employed to solve the optimisation problem. Both experimental and industrial cases are studied to validate the model. In addition, the impacts of cutting parameters on carbon emissions are discussed.

Our purpose is to study the interaction between referee and players in order to understand how altercations appear or not during a soccer match. We consider both process where by referee shows and imposes something to players and how player(s) live(s) subjectively these moments. Three matches have been analysed. Different traces of activities have been made in order to help referee and players to describe ex post their lived experiences. Several kinds of regulation by referee, of his interaction with player(s) have been highlighted as well as how some players, even if they live situations contrasting with what referee imposes, are able to project themselves in referee's setting. [ABSTRACT FROM AUTHOR]

Soil water potential and fertilizer nutrients are the two main factors affecting rice growth and development. A soil‐grown experiment was conducted using mid‐season japonica rice cultivar Xudao 3 with three different nitrogen (N) fertilization rates: (i) none, (ii) moderate nitrogen (240 kg ha–1), and (iii) high nitrogen (360 kg ha–1) and three irrigation regimes: (i) submerged irrigation (0 kPa), (ii) alternate wetting and moderate drying (–20 kPa), and (iii) alternate wetting and severe drying (–40 kPa). In the same N level, root length, root dry weight, root activity (represented by root‐bleeding sap), net photosynthetic rates at main growth stages, and ATPase activity during the grain‐filling stage are higher under the treatment of alternate wetting and moderate drying, when compared with those of submerged irrigation. Meanwhile, non‐structural carbohydrate (NSC) remobilization and shoot dry accumulation are also increased from heading to maturity, which contribute to higher grain yield and higher nitrogen‐use efficiency. In the same irrigation regime, root‐bleeding sap, NSC remobilization, and ATPase are increased significantly under the moderate‐N treatment compared with those of the high‐N treatment, which contribute to higher nitrogen‐use efficiency. However, no significant difference exists in grain yield and crop growth rate. These results indicate that the coordinated relationship between the root and shoot, especially increased root length, enhanced root‐bleeding sap, increased NSC remobilization, enhanced shoot dry accumulation, and ATPase activity during the grain‐filling stage, can promote rice yield and nitrogen‐use efficiency by using the appropriate nitrogen application and alternate wetting and moderate drying. Core IdeasRoot and shoot traits were significantly different in response to irrigation regime and nitrogen level treatment.Alternated wetting/moderate drying interacted with moderate N to coordinate the development of root and shoot.Deeper roots increased root‐bleeding sap, NSC remobilization from stems to grain, and activity of grain sink.Greater root length (via root‐shoot relationships) contribute to increased yield and enhanced N‐use efficiency.Alternated wetting/drying irrigation with moderate N promotes grain filling and increased yield and N‐use.

Although enantioselective C−H silylation has progressed rapidly in recent years, little mechanistic information on these reactions is available, especially for C−H silylation with dihydrosilanes toward silicon-stereogenic silanes. Here, we report a thorough combined experimental and theoretical mechanistic study on the rhodium-/Josiphos-catalyzed intramolecular enantioselective C−H silylation of dihydrosilanes for the construction of silicon-stereogenic centers. A rhodium silyl dihydride complex was identified as the resting state in the catalytic cycle, which was generated via a facile silyl metal migration process. This key resting state was also synthesized and characterized by X-ray crystallographic analysis. Density functional theory calculations were conducted to elucidate the full picture of the mechanism and shed light on the origin of the observed enantioselectivity and the racemization process in the reaction. With the understanding of the mechanism, both enantioenriched tetraorganosilanes and monohydrosilanes could be synthesized with decent yields and enantiomeric excess, respectively.

Contact twinning with the so-called "macle" form or other shapes are often found in natural diamond crystals. However, the surface microtopographic features associated with twinning have been less investigated. Here, the surface dissolution and growth features seen on the twin boundaries, including the re-entrant angles revealed by differential interference contrast microscope and SEM techniques in 170 natural diamond crystals mainly from Argle mine, Australia are described and summarized. The hexagonal pits, rhombic pits along with higher symmetry observed at the twin boundaries together with dislocations and their formation processes are discussed.

As a byproduct in the pyrolusite leaching process with SO2, the existence of MnS2O6will decrease the purity of MnSO4produced by leaching. For obtaining MnSO4with satisfactory quality, it is beneficial to decrease the formation of MnS2O6during the leaching process. A study on the formation characteristics of dithionate and sulfate formed in pyrolusite leaching process with SO2was carried out. The results indicated that $${\text{S}}_{ 2} {\text{O}}_{ 6}^{ 2- }$$ S2O62- formation and mole ratio of $${{{\text{S}}_{ 2} {\text{O}}_{ 6}^{ 2- } } \mathord{\left/ {\vphantom {{{\text{S}}_{ 2} {\text{O}}_{ 6}^{ 2- } } {{\text{SO}}_{ 4}^{ 2- } }}} \right. \kern-0pt} {{\text{SO}}_{ 4}^{ 2- } }}$$ S2O62-/SO42- increased with increasing initial pH, liquid–solid ratio and SO2concentration, but was independent of particle size and stirring speed when particle size was less than 200 μm and stirring speed exceeded 400 rpm. The suitable conditions for obtaining MnSO4product was 45  C and 0.4 mol L−1H+concentration with $${\text{S}}_{ 2} {\text{O}}_{ 6}^{ 2- }$$ S2O62- concentration and $${\text{S}}_{ 2} {\text{O}}_{ 6}^{ 2- } /{\text{SO}}_{ 4}^{ 2- }$$ S2O62-/SO42- ratio were lower than 0.7 g L−1and 0.02. Besides, the molar ratio of $${\text{S}}_{ 2} {\text{O}}_{ 6}^{ 2- }$$ S2O62- to $${\text{SO}}_{ 4}^{ 2- }$$ SO42- (R) was put forward as a correlated parameter to evaluate the formation of reaction products, whose kinetics was analyzed in depth. The kinetic equation was related to reaction temperature, H+and SO2concentration, and the calculated reaction orders for SO2concentration and initial H+were 0.27 and − 0.17, the activation energy was 9696 J mol−1.

This paper presents a Provenance-based what-if analysis approach (PBWA) for data mining processes, so decision makers can examine the latest mining result under hypothetical business contexts. It fills the gap that data mining only reveals past status of enterprises with historical data. Provenance information is a kind of metadata of data mining processes. PBWA uses it to identify relevant operation path and intermediate results that is affected by hypothetical business contexts. It refreshes the mining result by partially rerunning the affected portions. Different from previous studies only for relational operations, PBWA can take more general operations into account. Besides, it focuses on the whole mining processes. Experiments demonstrate that when the affected ratio is less than 74% and 87% in different contexts, PBWA can achieve better time performance.

Supplemental Digital Content is available in the text.

The traditional Dammann grating is a phase-only modulation, and its theoretical foundation is based on far-field diffraction. Here we extend the traditional Fresnel zone plate (FZP) into a Fresnel–Dammann zone plate (FDZP), which is, in essence, considered as a FZP with Dammann modulation. Different from the Dammann grating, a single FDZP can generate array illumination from the near field to the far field by means of amplitude-only modulation in the absence of phase modulation. We then give some array illuminations operated in a water window to validate the feasibility and validity. This kind of wave-front modulation technology can be applied to array focusing and imaging from the x-ray to the EUV region.

Background Research indicates that the socioeconomic status (SES) of individuals and the area where they live are related to initial peritonitis and outcomes in peritoneal dialysis (PD). We conducted a retrospective, multi-center cohort study in China to examine these associations.Methods Data on 2,171 PD patients were collected from 7 centers, including baseline demographic, socioeconomic, and laboratory data. We explored the potential risk factors for initial peritonitis and outcomes using univariate Cox regression and unadjusted binary logistic regression. Then, we used propensity score matching to balance statistically significant risk factors for initial peritonitis and outcomes, and Kaplan-Meier survival analysis to compare differences in peritonitis-free rates between different groups of participants after matching.Results A total of 563 (25.9%) initial episodes of peritonitis occurred during the study period. The Kaplan-Meier peritonitis-free rate curve showed high-income patients had a significantly lower risk than low-income patients (p= 0.007) after matching for age, hemoglobin, albumin, and regional SES and PD center. The risk of treatment failure was significantly lower in the high-income than the low-income group after matching for the organism causing peritonitis and PD center: odds ratio (OR) = 0.27 (0.09 – 0.80, p= 0.018). Regional SES and education were not associated with initial peritonitis and outcomes.Conclusions Our study demonstrates low individual income is a risk factor for the initial onset of peritonitis and treatment failure after initial peritonitis.

A computational molecular design strategy, complemented by UV/vis absorption and time-resolved electron paramagnetic resonance (EPR) spectra measurements, is employed to guide the search for active molecules for a room-temperature maser that can achieve continuous-wave operation. Focusing on linear polyacenes and diaza-substituted forms, our goal is to model how important maser properties are influenced by acene length and location of nitrogen substitution. We find that tetracene, its diaza-substituted forms (5,11-, 1,7-, and 2,8-diazatetracene), and anthracene possess singlet to triplet intersystem crossing rates highly favorable toward masing. The diaza-substituted forms of pentacene (6,13-, 5,12-, 1,8-, and 2,9-diazapentacene) also stand out as ideal candidates due to their similarity to the working pentacene prototype. A steady-state population analysis suggests the working conditions under which continuous-wave masing can be achieved for these molecules. Operational frequencies are estimated from calculated zero field splitting parameters.

Purpose: This article aims to report the second part of the interview with Dr Bor-Shiuan Cheng on his insights into Chinese indigenous management research, including challenges and future directions. Design/methodology/approach: This paper is based on a recent interview with Dr Bor-Shiuan Cheng. Findings: The biggest challenge for current Chinese management research is the administrative system and restrictive publication policy. Under the current system, it is best for researchers to consider a dual approach to research. That is, research must be relevant to local issues and significant to the international community. Research limitations/implications: The system that might sabotage academic system needs to be changed. And future leadership studies should be focused on developing mindful and moral leaders. Originality/value: The interview provides an insightful view on the current challenges of Chinese management research and valuable advice from Dr Cheng, who also showed the future direction of leadership studies.

We successfully extend the standard Fibonacci zone plates with two on-axis foci to the generalized Fibonacci photon sieves (GFiPS) with multiple on-axis foci. We also propose the direct and inverse design methods based on the characteristic roots of the recursion relation of the generalized Fibonacci sequences. By switching the transparent and opaque zones, according to the generalized Fibonacci sequences, we not only realize adjustable multifocal distances but also fulfill the adjustable compression ratio of focal spots in different directions.

Stroke is a leading cause of death and disability worldwide. Ischemic stroke is the dominant subtype of stroke and results from focal cerebral ischemia due to occlusion of major cerebral arteries. Thus, the restoration or improvement of reduced regional cerebral blood supply in a timely manner is very critical for improving stroke outcomes and poststroke functional recovery. The recovery from ischemic stroke largely relies on appropriate restoration of blood flow via angiogenesis. Newly formed vessels would allow increased cerebral blood flow, thus increasing the amount of oxygen and nutrients delivered to affected brain tissue. Angiogenesis is strictly controlled by many key angiogenic factors in the central nervous system, and these molecules have been well-documented to play an important role in the development of angiogenesis in response to various pathological conditions. Promoting angiogenesis via various approaches that target angiogenic factors appears to be a useful treatment for experimental ischemic stroke. Most recently, microRNAs (miRs) have been identified as negative regulators of gene expression in a post-transcriptional manner. Accumulating studies have demonstrated that miRs are essential determinants of vascular endothelial cell biology/angiogenesis as well as contributors to stroke pathogenesis. In this review, we summarize the knowledge of stroke-associated angiogenic modulators, as well as the role and molecular mechanisms of stroke-associated miRs with a focus on angiogenesis-regulating miRs. Moreover, we further discuss their potential impact on miR-based therapeutics in stroke through targeting and enhancing post-ischemic angiogenesis.

With the increase capacity of wind turbines, grounding device's influence on the equipment and personal safety is becoming more and more significant. In order to calculate the grounding resistance of a wind turbine more accurately, in this paper, based on the Neumann integral formula and the average potential method is applied to derive a formula which can calculate the value of grounding resistance. A general MATLAB program corresponding to the calculation formula is compiled. By comparing the numerical value with the empirical analysis results and building a grounding resistance measurement test platform the correctness of the formulas and program is verified.