A pressure-sensitive rheological origin of high friction angles of granular matter observed in NASA–MGM project

An abnormally high peak friction angle of Ottawa sand was observed in(National Aeronautics and Space Administration) NASA–(Mechanics of Granular Materials) MGM tests in microgravity conditions on the space shuttle. Previous investigations have been unsuccessful in providing a constitutive insight into this behavior of granular materials under extremely low effective stress conditions. Here, a recently proposed unified constitutive model for transient rheological behavior of sand and other granular materials is adopted for the analytical assessment of high peak friction angles. For the first time, this long-eluded behavior of sand is attributed to a hidden rheological transition mechanism, that is not only rate-sensitive, but also pressure-sensitive. The NASA–MGM microgravity conditions show that shear-tests of sand can be performed under abnormally low confining stress conditions. The pressure-sensitive behavior of granular shearing that is previously ignored is studied based on the μ(I) rheology and its variations. Comparisons between the model and the NASA microgravity tests demonstrate a high degree of agreement. The research is highly valid for pressure-sensitive and rate-dependent problems that occur during earthquakes, landslides, and space exploration.

不同CRISPR/Cas9供体适配基因编辑系统的比较及优化研究

在哺乳动物细胞中进行基因敲入通常采用同源定向修复(homology-directed repair,HDR)机制将外源DNA模板整合到目标基因组靶点中。然而HDR效率往往较低,其中外源DNA模板与目标基因组靶点的共定位是关键限制因素之一。为提高CRISPR/Cas9系统介导的HDR效率,本团队及前人研究将不同接头蛋白与SpCas9蛋白融合表达,利用其与特异性DNA序列结合的特性,构建了多种CRISPR/SpCas9供体适配基因编辑系统。为了便于比较、优化不同CRISPR/Cas9供体适配系统,本研究利用这些系统在HEK293T细胞GAPDH和ACTB基因末位外显子3′-端进行了eGFP基因敲入,并采用了优化的供体DNA模板设计方式,通过PCR和Sanger测序检测敲入的准确性,流式细胞分析进行敲入效率的检测。结果表明,将yGal4BD、hGal4BD、hLacI、hTHAP11和N57等接头蛋白与SpCas9蛋白C-端融合对其活性均无显著性影响;在GAPDH位点上,SpCas9融合yGal4BD、hGal4BD、hLacI和hTHAP11的供体适配系统等均能显著提高敲入效率;在ACTB位点上,SpCas9融合yGal4BD和hGal4BD能显著提高敲入效率;且增加供体DNA模板中的结合序列(binding sequence,BS)数量,有利于提高SpCas9-hTHAP11系统介导的敲入效率。总之,本研究比较并优化了不同的CRISPR/Cas9供体适配基因编辑系统,为后续相关的基因编辑应用研究提供了参考和借鉴。

Mechanical responses of anchoring structure under triaxial cyclic loading

Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and failure.This study develops an experimental device designed to test AS under triaxial loads.The device enables the investigation of the mechanical response,failure mode,instability assessment criteria,and anchorage effect of AS subjected to combined cyclic dynamic-static triaxial stress paths.The results show that the peak bearing strength is positively correlated with the anchoring matrix strength,anchorage length,and edgewise compressive strength.The bearing capacity decreases significantly when the anchorage direction is severely inclined.The free face failure modes are typically transverse cracking,concave fracturing,V-shaped slipping and detachment,and spallation detachment.Besides,when the anchoring matrix strength and the anchorage length decrease while the edgewise compressive strength,loading rate,and anchorage inclination angle increase,the failure intensity rises.Instability is determined by a negative tangent modulus of the displacement-strength curve or the continued deformation increase against the general downward trend.Under cyclic loads,the driving force that breaks the rock mass along the normal vector and the rigidity of the AS are the two factors that determine roadway stability.Finally,a control measure for surrounding rock stability is proposed to reduce the internal driving force via a pressure relief method and improve the rigidity of the AS by full-length anchorage and grouting modification.

Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2022

BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and treatment.Understanding the evolution and current state of research in this field is vital.AIM To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic evolution.METHODS This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the"bibliometrix"R package,VOSviewer,and CiteSpace.The analysis focused on the distribution of publications,contributions by institutions and countries,and trends in keywords.The methods included data synthesis,network analysis,and visualization of international collaboration networks.RESULTS This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and collaboration.It highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer Institute.The last five years,substantial advancements have been made,representing nearly 45%of the examined literature.Publication rates have dramatically increased,from 20 articles in 2002 to 112 in 2022,reflecting intensified research efforts.This study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication outlet.This shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN risks.CONCLUSION This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research emphasis.This calls for enhanced global collaboration and integration of artificial intelligence to improve cancer prevention and treatment accuracy,ultimately enhancing worldwide patient care.

Mimicking aneurysm in a patient with chronic occlusion of the left middle cerebral artery:A case report

BACKGROUND With the popularization of various cerebrovascular imaging methods and increased attention to the field,more cerebrovascular diseases are being detected in asymptomatic patients.Different cerebrovascular diseases are typically isolated but occasionally occur simultaneously,causing difficulties in diagnosis and treatment.Morphological changes in the collateral circulation of blood vessels in chronic cerebral artery occlusion patients are slow and dynamic,intercepting morphological development at a specific moment.Excessive reliance on single imaging tests such as digital subtraction cerebral angiography(DSA)can lead to misdiagnosis.CASE SUMMARY We report a 52-year-old male who was admitted to our department for treatment of an unruptured aneurysm during a follow-up examination for brain trauma after 1 mo.Computed tomography(CT)scan was negative,but CT angiography(CTA)revealed a sac-like bulge at the bifurcation of the left middle cerebral artery.DSA revealed an unruptured aneurysm with unique scapular morphology.The stump of a middle cerebral artery occlusion was observed during exposure during aneurysm clipping surgery,and the diagnosis of chronic cerebral artery occlusion was confirmed intraoperatively.This case was confusing because of the peculiar morphology of the arterial stump and compensatory angiogenesis due to multiple cerebral artery stenoses observed on preoperative CTA and DSA.The surgery did not cause secondary damage to the patient,and medical treatment for risk factors was continued postoperatively.CONCLUSION Multiple cerebral arterial stenoses can occur in conjunction with aneurysms or arteriovenous malformations,and their unique morphology can lead to misdiagnosis.

晶粒尺寸和温度对工业纯钛变形机制的影响

为了研究晶粒尺寸和加工温度对工业纯钛变形行为的影响,分别在室温和液氮温度下对平均晶粒尺寸为2、9、23和51μm的样品进行单轴拉伸实验,采用背散射电子衍射技术(EBSD)和透射电子显微镜技术(TEM)表征样品的显微组织和织构。结果表明,室温条件下位错滑移是主要的变形机制,而液氮温度下拉伸的样品中有丰富的变形孪晶被激活,其中包括{1012}拉伸孪晶、{1122}压缩孪晶和{1122}-{1012}二次孪晶。这揭示液氮温度条件下塑性变形模式从位错滑移到动态孪生的转变,这也是具有较大晶粒尺寸的样品在液氮温度下依然具有优异力学性能的主要原因。另外,还提出了一种改进的Hall-Petch关系式,可用于在液氮温度条件下定量表征平均晶粒尺寸和孪晶对工业纯钛拉伸屈服强度的影响。

Changes in wintering Hooded Cranes and their habitats at Chongming Dongtan over the past 20 years

The Hooded Crane(Grus monacha)is listed as a Vulnerable species in the IUCN red list.Tidal wetland(tideland),the major habitat for wintering Hooded Cranes at East China’s Chongming Dongtan,has dramatically changed in the past two decades,but there is limited knowledge about the population and habitat changes of the Hooded Cranes.This study investigated the population size and distribution of wintering Hooded Cranes at Chongming Dongtan from 2000 to 2021.We used remote sensing images combined with a vegetation classification algorithm to analyse the distribution of saltmarsh vegetation.The quadrat method was used to investigate the density and weight of the underground corms of Sea Bulrush(Scirpus mariquter),the main food on tideland for the Hooded Cranes.From 2000 to 2021,the population number of wintering Hooded Cranes at Chongming Dongtan remained stable at approximately 100.In 2000,the area of Scirpus spp.and Common Reed(Phragmites australis)accounted for approximately half of the total saltmarsh area at Chongming Dongtan,respectively.The invasive Smooth Cordgrass(Spartina alterniflora)rapidly expanded on tideland in the 2000s while the Scirpus spp.was competed out and thus significantly reduced in area.After the implementation of an ecological project to control Smooth Cordgrass and to restore Scirpus spp.in the 2010s,the area of the Smooth Cordgrass decreased considerably while the area of Scirpus spp.increased.The corms of Sea Bulrush decreased on the southeastern tideland during the study period,which might be the cause of the northward movement of the foraging Hooded Cranes on tideland.We also found Hooded Cranes foraged crops in the nearby farmland in mid-winter,causing human-bird conflicts in the recent decade.Our results found that changes in habitat and food conditions on tideland impacted wintering Hooded Cranes.Foraging in farmland with human disturbance in the recent decade might be related to insufficient food on tideland.We suggest active intervention to accelerate the restoration of Sea Bulrush on tideland and reduce human disturbance in farmland to improve the habitat quality of the wintering Hooded Crane at Chongming Dongtan.

HD-Zip Transcription Factor is Responsible for No-Lobed Leaf in Watermelon(Citrullus lanatus L.)

Leaf is a vital organ of plants that plays an essential role in photosynthesis and respiration.As an important agronomic trait in leaf development,leaf shape is classified into lobed,entire(no-lobed),and serrated in most crops.In this study,two-lobed leaf watermelon inbred lines WT2 and WCZ,and a no-lobed leaf watermelon inbred line WT20 were used to create two F_(2)populations.Segregation analysis suggested that lobed leaves were dominant over the no-lobed leaves,and it was controlled by a signal gene.A locus on watermelon chromosome 4 controlling watermelon lobed/no-lobed leaves was identified through BSA-seq strategy combined with linkage analysis.The candidate gene was fine-mapped to a 61.5 kb region between 21,224,481 and 21,285,957 bp on watermelon chromosome 4 using two F_(2)populations.Four functional genes were annotated in the candidate region,while sequences blast showed that there was a single-base deletion(A/-)only in the exon of Cla018360,which resulted in premature termination of translation in the no-lobed leaf lines.Function prediction showed that Cla018360 encodes an HD-Zip protein that has been reported to regulate the development of leaf shape.The single-base deletion also occurred in the HD-Zip domain.We inferred that the Cla018360 gene is the candidate gene for regulating the development of lobed/no-lobed leaves in watermelon.Gene expression analysis showed that Cla018360 was highly expressed in young leaves.Phylogenetic analysis showed that Cla018360 had a close genetic relationship with AtHB51,which had been reported to regulate the formation of leaf shape in Arabidopsis.Furthermore,transcriptome analysis showed that a total of 333 differentially expressed genes were identified between WT2 and WT20,of which 115 and 218 genes were upregulated and downregulated in no-lobed leaved watermelon WT20.This study not only provides a good entry point for studying leaf development but also provides foundational insights into breeding for special plant architecture in watermelon.

BARN:Behavior-Aware Relation Network for multi-label behavior detection in socially housed macaques

Quantification of behaviors in macaques provides crucial support for various scientific disciplines,including pharmacology,neuroscience,and ethology.Despite recent advancements in the analysis of macaque behavior,research on multi-label behavior detection in socially housed macaques,including consideration of interactions among them,remains scarce.Given the lack of relevant approaches and datasets,we developed the Behavior-Aware Relation Network(BARN)for multi-label behavior detection of socially housed macaques.Our approach models the relationship of behavioral similarity between macaques,guided by a behavior-aware module and novel behavior classifier,which is suitable for multi-label classification.We also constructed a behavior dataset of rhesus macaques using ordinary RGB cameras mounted outside their cages.The dataset included 65?913 labels for19 behaviors and 60?367 proposals,including identities and locations of the macaques.Experimental results showed that BARN significantly improved the baseline SlowFast network and outperformed existing relation networks.In conclusion,we successfully achieved multilabel behavior detection of socially housed macaques with both economic efficiency and high accuracy.

The Regularized WSM6 Microphysical Scheme and Its Validation in WRF 4D-Var

A cold cloud assimilation scheme was developed that fully considers the water substances,i.e.,water vapor,cloud water,rain,ice,snow,and graupel,based on the single-moment WSM6 microphysical scheme and four-dimensional variational(4D-Var)data assimilation in the Weather Research and Forecasting data assimilation(WRFDA)system.The verification of the regularized WSM6 and its tangent linearity model(TLM)and adjoint mode model(ADM)was proven successful.Two groups of single observation and real sounding data assimilation experiments were set up to further verify the correctness of the assimilation scheme.The results showed that the consideration of ice,snow,and graupel in the assimilation system of the 4D-Var,as opposed to their omission in the warm rain Kessler scheme,allowed the water substances to be reasonably updated,further improving the forecast.Before it can be further applied in the assimilation of observational data,radar reflectivities,and satellite radiances,the cold cloud assimilation scheme needs additional verification,including using conventional ground and sounding observations in the 4D-Var assimilation system.

电加热微电极传热模式的结构依赖性研究

近年来,电加热微电极在电分析化学中得到了广泛的关注。研究表明,在高温下促进质量传输和反应动力学通常会导致电流信号增加。然而,目前还没有关于微电极内部传热的研究,这对于微传感器的设计和操作是必要的。本文利用有限元模拟软件(COMSOL)来分析影响表面温度(T_(s))的因素,这对线圈加热的微盘电极的加热能力至关重要。电极表面和加热铜线底部之间的距离也与T_(s)(R^(2)=1)有良好的线性关系。考虑到成本,25 mm长的金丝足以获得相对较高的T_(s)。此外,当电极材料为金且金盘直径为0.2 mm时,可以获得最高的Ts。本文还研究了不同温度下加热铜线直径与电流的关系。仿真结果有望为电加热微传感器的设计和实际应用提供重要帮助。

Identification of candidate genes that regulate the trade-off between seedling cold tolerance and fruit quality in melon (Cucumis melo L.)

Trade-offs between survival and growth are widely observed in plants.Melon is an annual,trailing herb that produces economically valuable fruits that are traditionally cultivated in early spring in China.Melon seedlings are sensitive to low temperatures,and thus usually suffer from cold stress during the early growth period.However,little is known about the mechanism behind the trade-offs between seedling cold tolerance and fruit quality in melon.In this study,a total of 31 primary metabolites were detected from the mature fruits of eight melon lines that differ with respect to seedling cold tolerance;these included 12 amino acids,10 organic acids,and 9 soluble sugars.Our results showed that concentrations of most of the primary metabolites in the cold-resistant melons were generally lower than in the cold-sensitive melons;the greatest difference in metabolite levels was observed between the cold-resistant line H581 and the moderately cold-resistant line HH09.The metabolite and transcriptome data for these two lines were then subjected to weighted correlation network analysis,resulting in the identification of five key candidate genes underlying the balancing between seedling cold tolerance and fruit quality.Among these genes,CmEAF7 might play multiple roles in regulating chloroplast development,photosynthesis,and the ABA pathway.Furthermore,multi-method functional analysis showed that CmEAF7 can certainly improve both seedling cold tolerance and fruit quality in melon.Our study identified an agriculturally important gene,CmEAF7,and provides a new insight into breeding methods to develop melon cultivars with seedling cold tolerance and high fruit quality.

醇硫基丙烷磺酸钠对电解高性能锂电铜箔的影响

电解铜箔因其工艺简单、经济价值高,已广泛应用于印制线路板和锂离子电池领域。研究表明在电解制箔过程中,加入微量添加剂即可大幅度提高电解铜箔性能。因此,在基础电解液(312.5 g·L^(-1)CuSO_(4)·5H_(2)O,100 g·L^(-1)H_(2)SO_(4),50 mg·L^(-1)Cl^(-))基础上,加入添加剂考察了电解液的电化学行为以及对铜箔表面形貌、结构以及性能的影响。实验选取了醇硫基丙烷磺酸钠(HP)、水解蛋白(HVP)和N,N-二甲基硫代甲酰胺丙烷磺酸钠(DPS)作为组合添加剂,利用扫描电镜(SEM)、X射线洐射(XRD)以及电化学分析等方法,重点考察了组合添加中HP对铜箔表面形貌和物理性能的影响。研究结果表明,在组合添加剂体系中HP具有较强的去极化作用,可以加速铜核的生长,且具有增强铜(200)晶面的择优生长取向。HP与DPS、HVP的协同作用可以进一步减小电解铜箔的晶粒尺寸,降低表面粗糙,提高铜箔力学性能和耐腐蚀性能。所制备的电解铜箔均匀致密,平均晶粒尺寸为29.2 nm、平均粗糙度为1.12μm、平均抗拉强度为399.5 MPa且耐蚀性能优越,是锂离子电池负极集流体的理想材料,具有较高的商业价值。

疏风明目方超声雾化对过敏性结膜炎患者泪膜稳定性及泪液相关指标的影响

目的:观察疏风明目方超声雾化对过敏性结膜炎患者泪膜稳定性及泪液相关指标的影响。方法:将140例过敏性结膜炎患者随机分为两组,对照组70例给予盐酸奥洛他定滴眼液联合生理盐水雾化治疗,观察组70例给予盐酸奥洛他定滴眼液联合疏风明目方超声雾化治疗。连续治疗14d后,比较两组临床疗效、治疗前后单项症状(流泪、痒感、畏光、异物感)、泪膜稳定性(BUT、FL)、泪液相关指标[嗜酸性细胞阳离子蛋白(ECP)、HA、IgE]。结果:观察组治疗后总有效率高于对照组(90.7%vs74.3%,P<0.05);两组治疗后单项症状积分均低于治疗前,且观察组均低于对照组(P<0.05);两组治疗后BUT均高于治疗前,FL均低于治疗前,且观察组改善程度均优于对照组(P<0.05);两组治疗后泪液HA、ECP、IgE水平均低于治疗前,且观察组改善程度均优于对照组(P<0.05)。结论:疏风明目方超声雾化治疗能够改善过敏性结膜炎患者泪液相关指标,提高泪膜稳定性,有助于缓解局部变态反应,改善患者临床症状。

In-situ TiC Reinforced Composite Coating Produced by Powder Feeding Laser Cladding

A Ni-base alloy composite coating reinforced with TiC particles of various shapes and sizes on medium carbon steel substrate was produced by multilayer laser cladding. The chemical compositions, microstructures and surface morphology of the cladded layer were analyzed using energy dispersive X-ray spectroscopy （EDX）, scanning electron microscope （SEM）, and X-ray diffractometry （XRD）. The experimental results showed that an excellent metallurgical bonding between the coating and the substrate was obtained. The microstructure of the coating was mainly composed of γ-Ni dendrites, a small amount of CrB, Ni3B, M23C6 and dispersed TiC particles. Much more and larger TiC particles formed in the overlapping zone, which led to a slightly higher microhardness of this zone. The maximum microhardness of the coating was about HV0.21200. The effects of the laser processing parameters on the microstructures and properties of coating were also investigated.

Comprehensive analysis of NAC transcription factors and their expression during fruit spine development in cucumber (Cucumis sativus L.)

The cucumber(Cucumis sativus L.)is an important vegetable crop worldwide,and fruit trichomes or spines are an important trait for external fruit quality.The mechanisms underlying spine formation are not well understood,but the plant-specific NAC family of transcription factors may play important roles in fruit spine initiation and development.In this study,we conducted a genome-wide survey and identified 91 NAC gene homologs in the cucumber genome.Clustering analysis classified these genes into six subfamilies;each contained a varying number of NAC family members with a similar intron–exon structure and conserved motifs.Quantitative real-time PCR analysis revealed tissue-specific expression patterns of these genes,including 10 and 12 that exhibited preferential expression in the stem and fruit,respectively.Thirteen of the 91 NAC genes showed higher expression in the wild-type plant than in its near-isogenic trichome mutant,suggesting their important roles in fruit spine development.Exogenous application of four plant hormones promoted spine formation and increased spine density on the cucumber fruits;several NAC genes showed differential expression over time in response to phytohormone treatments on cucumber fruit,implying their essential roles in fruit-trichome development.Among the NAC genes identified,12 were found to be targets of 13 known cucumber micro-RNAs.Collectively,these findings provide a useful resource for further analysis of the interactions between NAC genes and genes underlying trichome organogenesis and development during fruit spine development in cucumber.

First genetic assessment of brackish water polychaete Tylorrhynchus heterochaetus: mitochondrial CO/sequences reveal strong genetic differentiation and population expansion in samples collected from southeast China and north Vietnam

Tylorrhynchus heterochaetus is a widespread benthic polychaete worm found in coastal brackish waters of the west Pacific.It has high ecological and economic value as a biomarker of water quality and as a high-quality feed in aquaculture and fisheries and is considered a delicacy in some areas of Asia.However,it has experienced a marked reduction in recent years due to overexploitation as well as changes in the environment and climate.Here,to comprehensively understand its genetic background and thus provide insights for better conservation and utilization of this species,we assessed the genetic variability and demographic history of T.heterochaetus individuals sampled from eight locations along the coasts of southeast China and north Vietnam based on mitochondrial cytochrome c oxidase I(COI)sequences.We observed high haplotype diversity(Hd),with an average of 0.926,but relatively low nucleotide diversity(π),with a mean of 0.032 across all samples.A total of 94 polymorphic sites and 85 haplotypes were identified among 320 individuals.The pairwise genetic distances among haplotypes ranged from 0.001 to 0.067,with the high intraspecific divergence possibly reflecting geographic isolation and gene pool fragmentation.Significant genetic structures were revealed among the studied locations;specifically,the eight locations could be treated as six genetically different populations based on pairwiseΦST results(0.026–0.951,P<0.01).A significant pattern of isolation-by-distance was detected between the genetic and geographic distances(r=0.873,P=0.001).Three geographic lineages were defined based on phylogenetic tree and network analyses of COI haplotypes.AMOVA results indicated that genetic variations mainly occurred among the three lineages(89.96%).Tests of neutrality and mismatch distribution suggested that T.heterochaetus underwent recent population expansion.These results provide the first report on the genetic status of T.heterochaetus and will be valuable for the management of genetic resources and better understanding of the ecology and evolution in this species.

Relationships among KRAS mutation status, expression of RAS pathway signaling molecules, and clinicopathological features and prognosis of patients with colorectal cancer

BACKGROUND The RAS/RAF/MEK/ERK and PI3 K/AKT/mTOR signaling pathways all belong to mitogen-activated protein kinase(MAPK) signaling pathways, Mutations in any one of the upstream genes(such as the RAS gene or the BRAF gene) may be transmitted to the protein through transcription or translation, resulting in abnormal activation of the signaling pathway. This study investigated the relationship between the KRAS gene mutation and the clinicopathological features and prognosis of colorectal cancer(CRC), and the effect of KRAS mutations on its associated proteins in CRC, with an aim to clarify the cause of tumor progression and drug resistance caused by mutation of the KRAS gene.AIM To investigate the KRAS gene and RAS pathway signaling molecules in CRC and to analyze their relationship with clinicopathological features and prognosis METHODS Colorectal cancer tissue specimens from 196 patients were analyzed for KRAS mutations using quantitative polymerase chain reaction and for KRAS, BRAF,MEK, and ERK protein expression levels using immunohistochemistry of tumor microarrays. To analyze differences of RAS pathway signaling molecule expression levels in different KRAS gene status, the relationships between these parameters and clinicopathological features, 4-year progression-free survival, and overall survival were analyzed by independent sample t test, Kaplan-Meier plots,and the log-rank test. Predictors of overall and disease-free survival were assessed using a Cox proportional hazards model.RESULTS Of the 196 patients, 62(32%) carried mutations in codon 12(53/62) or codon 13(9/62) in exon 2 of the KRAS gene. KRAS, BRAF, ERK, and MEK protein expression was detected in 71.4%, 78.8%, 64.3%, and 50.8% of CRC tissues,respectively. There were no significant differences between KRAS mutation status and KRAS, BRAF, MEK, or ERK protein levels. Positive expression of KRAS and ERK was associated with poor tumor differentiation, and KRAS expression was also associated with age < 56 years. MEK expression was significantly associated with distant metastasis(P < 0.05). The 4-year progression-free survival rate, but not overall survival rate, was significantly higher in patients with KRAS-negative tumors than in those with KRAS-positive tumors(P < 0.05), whereas BRAF, MEK,and ERK expression was unrelated to survival. Multivariate analysis showed that only the expression of KRAS protein was a risk factor for tumor recurrence(P <0.05). No other clinicopathological factors correlated with KRAS, BRAF, MEK, or ERK expression.CONCLUSION KRAS gene mutations do not affect downstream protein expression in CRC.KRAS protein is associated with poor tumor differentiation, older age, and a risk of tumor recurrence.

Aerodynamic-Parameter Identification and Attitude Control of Quad-Rotor Model with CIFER and Adaptive LADRC

Current research on quadrotor modeling mainly focuses on theoretical analysis methods and experimental methods,which have problems such as weak adaptability to the environment,high test costs,and long durations.Additionally,the PID controller,which is currently widely used in quadrotors,requires improvement in anti-interference.Therefore,the aforementioned research has considerable practical significance for the modeling and controller design of quadrotors with strong coupling and nonlinear characteristics.In the present research,an aerodynamic-parameter estimation method and an adaptive attitude control method based on the linear active disturbance rejection controller(LADRC)are designed separately.First,the motion model,dynamics model,and control allocation model of the quad-rotor are established according to the aerodynamic theory and Newton-Euler equations.Next,a more accurate attitude model of the quad-rotor is obtained by using a tool called CIFER to identify the aerodynamic parameters with large uncertainties in the frequency domain.Then,an adaptive attitude decoupling controller based on the LADRC is designed to solve the problem of the poor anti-interference ability of the quad-rotor and adjust the key control parameter b0 automatically according to the change in the moment of inertia in real time.Finally,the proposed approach is verified on a semi-physical simulation platform,and it increases the tracking speed and accuracy of the controller,as well as the anti-disturbance performance and robustness of the control system.This paper proposes an effective aerodynamic-parameter identification method using CIFER and an adaptive attitude decoupling controller with a sufficient anti-interference ability.

Melon short internode(CmSi)encodes an ERECTA-like receptor kinase regulating stem elongation through auxin signaling

Plant height is one of the most important agronomic traits that directly determines plant architecture,and compact or dwarf plants can allow for increased planting density and land utilization as well as increased lodging resistance and economic yield.At least four dwarf/semidwarf genes have been identified in different melon varieties,but none of them have been cloned,and little is known about the molecular mechanisms underlying internode elongation in melon.Here,we report map-based cloning and functional characterization of the first semidwarf gene short internode(Cmsi)in melon,which encodes an ERECTA-like receptor kinase regulating internode elongation.Spatial-temporal expression analyses revealed that CmSI exhibited high expression in the vascular bundle of the main stem during internode elongation.The expression level of CmSI was positively correlated with stem length in the different melon varieties examined.Ectopic expression of CmSI in Arabidopsis and cucumber suggested CmSI as a positive regulator of internode elongation in both species.Phytohormone quantitation and transcriptome analysis showed that the auxin content and the expression levels of a number of genes involved in the auxin signaling pathway were altered in the semidwarf mutant,including several well-known auxin transporters,such as members of the ABCB family and PINFORMED genes.A melon polar auxin transport protein CmPIN2 was identified by protein–protein interaction assay as physically interacting with CmSI to modulate auxin signaling.Thus,CmSI functions in an auxin-dependent regulatory pathway to control internode elongation in melon.Our findings revealed that the ERECTA family gene CmSI regulates stem elongation in melon through auxin signaling,which can directly affect polar auxin transport.