Optimization of Process Parameters for Cracking Prevention of UHSS in Hot Stamping Based on Hammersley Sequence Sampling and Back Propagation Neural Network-Genetic Algorithm Mixed Methods

In order to prevent cracking appeared in the work-piece during the hot stamping operation,this paper proposes a hybrid optimization method based on Hammersley sequence sampling( HSS),finite analysis,backpropagation( BP) neural network and genetic algorithm( GA). The mechanical properties of high strength boron steel are characterized on the basis of uniaxial tensile test at elevated temperatures. The samples of process parameters are chosen via the HSS that encourages the exploration throughout the design space and hence achieves better discovery of possible global optimum in the solution space. Meanwhile, numerical simulation is carried out to predict the forming quality for the optimized design. A BP neural network model is developed to obtain the mathematical relationship between optimization goal and design variables,and genetic algorithm is used to optimize the process parameters. Finally,the results of numerical simulation are compared with those of production experiment to demonstrate that the optimization strategy proposed in the paper is feasible.

On the role of wave breaking in ocean dynamics under typhoon Matsa in the Bohai Sea,China

The role of wave breaking(WB) in the ocean dynamics in the Bohai Sea,China under typhoon condition is systematically investigated utilizing a coupled wave-current model.The influences of WB on ocean dynamics and processes(mixing coefficient,temperature,mixed layer depth,and current) during the entire typhoon period(including the pre-typhoon,during-typhoon and after-typhoon stages) are comprehensively detected and discussed.Experimental results show that WB greatly enhances the turbulent mixing at about top 10 m depth under typhoon condition,the increase can be up to 10 times that of the normal weather.At the same time,WB generally strengthens the sea surface cooling by ~1.2°C at the during-typhoon stage,about 3 times that in normal weather.The mixed layer depth,is rapidly increased by ~1.6–3.6 m during typhoon due to WB,particularly,the deepening is stronger in the region from 120.5°E to 121.0°E on account of close to the typhoon eye.In addition,WB renders the current speed more uniformly within the entire depth in the Bohai Sea,the change in speed is ~0.2 m/s,whereas the alternation in current vector is generally opposite to the wind direction except for the typhoon eye region,reflecting that WB has an inhibitory effect on the typhoon-forced current change.The effects of WB on vertical mixing coefficient response to the typhoon rapidly,while the impacts of WB on temperature,and mixed layer depth present hysteretic responses to typhoon.Finally,the mechanisms and distribution characteristics of WB-induced mixing and tidal mixing are compared under typhoon condition.

Investigation on Inorganic Pollution Level in Surface Sediments of Naples and Salerno Bay

In this study, superficial marine sediments collected from 96 sampling sites were analyzed for 53 inorganic elements. Each sample was digested in aqua regia and analyzed by ICP-MS. A developed multifractal inverse distance weighted (IDW) interpolation method was applied for the compilation of interpolated maps for both single element and factor scores distributions. R-mode factor analysis have been performed on 23 of 53 analyzed elements. The 3 factor model, accounting 84.9% of data variability, were chosen, The three elemental associations obtained have been very helpful to distinguish anthropogenic from geogenic contribution. The aim of this study is to distinguish distribution patterns of pollutants on the sea floor of NaplesandSalernobays. In general, local lithologies, water dynamic and anthropogenic activities determine the distribution of the analyzed elements. To estimate pollution level in the area, Italian guidance, Canadian sediment quality guidance and Long’s criteria are chosen to set the comparability. As the results shows, arsenic and lead may present highly adverse effect to living creatures.

Revealing the role of CCoAOMT1: fine-tuning bHLH transcription factors for optimal anther development

The tapetum,a crucial innermost layer encompassing male reproductive cells within the anther wall,plays a pivotal role in normal pollen development.The transcription factors (TFs) bHLH010/089/091 redundantly facilitate the rapid nuclear accumulation of DYSFUNCTIONAL TAPETUM 1,a gatekeeper TF in the tapetum.Nevertheless,the regulatory mechanisms governing the activity of bHLH010/089/091 remain unknown.In this study,we reveal that caffeoyl coenzyme A O-methyltransferase 1 (CCoAOMT1) is a negative regulator affecting the nuclear localization and function of bHLH010 and bHLH089,probably through their K259 site.Our findings underscore that CCoAOMT1 promotes the nuclear export and degradation of bHLH010 and bHLH089.Intriguingly,elevated CCoAOMT1 expression resulted in defective pollen development,mirroring the phenotype observed in bhlh010 bhlh089 mutants.Moreover,our investigation revealed that the K259A mutation in the bHLH089 protein disrupted its translocation from the nucleus to the cytosol and impeded its degradation induced by CCoAOMT1.Importantly,transgenic plants with the probHLH089::bHLH089^(K259A)construct failed to rescue proper pollen development or gene expression in bhlh010 bhlh089 mutants.Collectively,these findings emphasize the need to maintain balanced TF homeostasis for male fertility.They firmly establish CCoAOMT1 as a pivotal regulator that is instrumental in achieving equilibrium between the induction of the tapetum transcriptional network and ensuring appropriate anther development.

Evaluating the Applicability and Health Benefits of the Graded Heat Health Risk Early Warning Model-Jinan City,Shandong Province,China,2022

What is already known about this topic?The heat health early warning model serves as an effective strategy for reducing health risks related to heatwaves and improving population adaptability.Several high-income countries have taken the lead in conducting research and implementing measures aimed at safeguarding their populations.What is added by this report?The graded heat health risk early warning model(GHREWM)in Jinan City has demonstrated efficacy in safeguarding males,females,individuals aged above 75 years,and those with cardiopulmonary diseases.During the summer of 2022,the warning stage of GHREWM contributed to the prevention of 10.9 deaths per million individuals,concurrently averting health-related economic losses estimated at approximately 227 million Chinese Yuan(CNY).What are the implications for public health practice?The GHREWM has the potential to enhance cities’adaptability to climate change.It is crucial to incorporate additional adverse health endpoint data in the development of early warning models,as this will improve their applicability and protective efficacy.

LncRNAs unraveling their sponge role in glioblastoma and potential therapeutic applications

Glioblastoma multiforme(GBM),the most common and aggressive primary brain tumor in adults,is the most malignant and still has no cure.However,the novel role of long non-coding RNAs(lncRNAs)in the pathogenesis of glioblastoma is attracting extensive attention.LncRNAs are transcribed RNA molecules over 200 nucleotides long that do not encode proteins.Unlike small non-coding RNAs,such as microRNAs(miRNAs),lncRNAs have more complex secondary and tertiary structures that enable them to interact with DNA,RNA,and proteins and perform multiple regulatory functions.LncRNAs act as molecular sponges,absorbing and sequestering other biomolecules,particularly miRNAs,thereby preventing these molecules from performing their normal functions.LncRNAs influence glioblastoma through gene expression regulation,molecular sponge capacity,epigenetic modulation,and signaling pathway interactions.In glioblastoma,a large number of lncRNAs have been found to be abnormally expressed,affecting tumor growth,invasion and resistance to treatment.Due to its regulatory role and disease-specific expression patterns,lncRNA has become a potential biomarker for glioblastoma and a promising new therapeutic target.This paper discusses the spongy role of lncRNAs in glioblastoma and its potential therapeutic applications,which will lay a foundation for our understanding of glioblastoma biology and the development of new diagnostic and therapeutic strategies in the future.

Quantitative analysis of work hardening and dynamic softening behaviors of Cu-6 wt pct Ag binary alloy based on true stress vs strain curves

The work hardening and dynamic softening behaviors of Cu-6 wt pct Ag binary alloy were studied by hot compression tests under temperature range of 700-850℃ at strain rates of 0.01-10s-1.The critical conditions for the onset of dynamic recrystallization (DRX) were determined based on the conventional strain hardening rate curves (dσ/dε versus σ).The progress of DRX was analyzed by constructing a model of volume fraction of DRX based on flow curves.The strain rate sensitivity (SRS) and activation volume V were calculated.The results show that the DRX almost can happen under all deformation conditions even at high Z deformations where dynamic recovery (DRV) is the main softening mechanism.The DRX fraction curves can well predict the DRX behavior.The strain has significant effects on SRS at the strain rates of 0.01s-1 and 10s-1 which are mainly due to off-equilibrium saturation of dislocation storage and annihilation while the effects of the temperature on the SRS are based on the uniformity of microstructure distribution.The formation of "forest" of dislocation is contributed to the low activation volume V*(about 168b3) which is independent of Z values at the initial deformation.The cross-slip due to dislocation piled up beyond the grain boundaries or obstacles is related to the low activation volume under the high Z deformation conditions at high strain (ε=0.6) while the fine DRX grains coarsed is the main reason for the high activation volume at low Z under the same strain conditions.

The evolution of sex chromosome dosage compensation in animals

The evolution of heteromorphic sex chromosomes shall lead to gene expression dosage problems,as in at least one of the sexes,the sex-linked gene dose has been reduced by half.It has been proposed that the transcriptional output of the whole X or Z chromosome should be doubled for complete dosage compensation in heterogametic sex.However,owing to the variability of the existing methods to determine the transcriptional differences between sex chromosomes and autosomes(S:A ratios)in different studies,we collected more than 500 public RNA-Seq data set from multiple tissues and species in major clades and proposed a unified computational framework for unbiased and comparable measurement of the S:A ratios of multiple species.We also tested the evolution of dosage compensation more directly by assessing changes in the expression levels of the current sex-linked genes relative to those of the ancestral sex-linked genes.We found that in mammals and birds,the S:A ratio is approximately 0.5,whereas in insects,fishes,and flatworms,the S:A ratio is approximately 1.0.Further analysis showed that the fraction of dosage-sensitive housekeeping genes on the X/Z chromosome is significantly correlated with the S:A ratio.In addition,the degree of degeneration of the Y chromosome may be responsible for the change in the S:A ratio in mammals without a dosage compensation mechanism.Our observations offer unequivocal support for the sex chromosome insensitivity hypothesis in animals and suggest that dosage sensitivity states of sex chromosomes are a major factor underlying different evolutionary strategies of dosage compensation.

High-performance fiber strain sensor of carbon nanotube/thermoplastic polyurethane@styrene butadiene styrene with a double percolated structure

In this work,a high-performance fiber strain sensor is fabricated by constructing a double percolated structure,consisting of carbon nanotube(CNT)/thermoplastic polyurethane(TPU)continuous phase and styrene butadiene styrene(SBS)phase,incompatible with TPU(CNT/TPU@SBS).Compared with other similar fiber strain sensor systems without double percolated structure,the CNT/TPU@SBS sensor achieves a lower percolation threshold(0.38 wt.%)and higher electrical conductivity.The conductivity of 1%-CNT/TPU@SBS(4.12×10^(-3) S·m^(-1))is two orders of magnitude higher than that of 1%-CNT/TPU(3.17×10^(-5) S·m^(-1))at the same CNT loading of 1 wt.%.Due to double percolated structure,the 1%-CNT/TPU@SBS sensor exhibits a wide strain detection range(0.2%-100%)and an ultra-high sensitivity(maximum gauge factor(GF)is 32411 at 100%strain).Besides,the 1%-CNT/TPU@SBS sensor shows a high linearity(R^(2)=0.97)at 0%-20%strain,relatively fast response time(214 ms),and stability(500 loading/unloading cycles).The designed sensor can efficiently monitor physiological signals and movements and identify load distribution after being woven into a sensor array,showing broad application prospects in wearable electronics.

Heritage tourism evolution in Guangfu Ancient City,Hebei Province,China:an analysis with the improved creative destruction model

Ancient cities and towns are popular tourism destinations worldwide.In this paper,Guangfu Ancient City in Yongnian County,Hebei Province,China,is taken as the case study and the modifed creative destruction model is applied as the analytical framework to evaluate the multiactor dynamics of heritage tourism development.A mixed method approach is adopted,including a local resident survey,in-depth interviews with staf of the Guangfu Ancient City tourism site and government ofcials responsible for the heritage conservation and tourism development of the site,and a review of online tourist reviews,relevant government documents and reports.Based on the modifed creative destruction model,local residents’attitudes towards tourism development,changes in tourist numbers,the level of business and government investments,and the motivations of diferent stakeholders in tourism development are assessed by synthesising on-site research,historical data and other materials.Then,the tourism development stages for Guangfu Ancient City are identifed as the precommodifcation stage before 2006,the early commodifcation stage from 2006 to 2011 and the advanced commodifcation stage from 2012 to 2017.The fndings indicate that with rapid increases in investments from both corporate and government sources and in the number of tourists,the attitude of local residents towards tourism development remained positive.The results show that instead of entering the initial destruction stage,Guangfu Ancient City is in the transition stage from advanced commodifcation to creative enhancement given the government’s dominant role in tourism development,the heritage conservation motives of tourism entrepreneurs,the benefts to residents from tourism development ensured by government policies,and the shift in tourist type to postmodern tourists with double demands.The applicability of the modifed creative destruction model is further discussed,and policy and management recommendations are generated to support the sustainable development of Guangfu Ancient City after the COVID-19 pandemic.