Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration

Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering.

Telencephalic stab wound injury induces regenerative angiogenesis and neurogenesis in zebrafish:unveiling the role of vascular endothelial growth factor signaling and microglia

After brain damage,regenerative angiogenesis and neurogenesis have been shown to occur simultaneously in mammals,suggesting a close link between these processes.However,the mechanisms by which these processes interact are not well understood.In this work,we aimed to study the correlation between angiogenesis and neurogenesis after a telencephalic stab wound injury.To this end,we used zebrafish as a relevant model of neuroplasticity and brain repair mechanisms.First,using the Tg(fli1:EGFP×mpeg1.1:mCherry)zebrafish line,which enables visualization of blood vessels and microglia respectively,we analyzed regenerative angiogenesis from 1 to 21 days post-lesion.In parallel,we monitored brain cell proliferation in neurogenic niches localized in the ventricular zone by using immunohistochemistry.We found that after brain damage,the blood vessel area and width as well as expression of the fli1 transgene and vascular endothelial growth factor(vegfaa and vegfbb)were increased.At the same time,neural stem cell proliferation was also increased,peaking between 3 and 5 days post-lesion in a manner similar to angiogenesis,along with the recruitment of microglia.Then,through pharmacological manipulation by injecting an anti-angiogenic drug(Tivozanib)or Vegf at the lesion site,we demonstrated that blocking or activating Vegf signaling modulated both angiogenic and neurogenic processes,as well as microglial recruitment.Finally,we showed that inhibition of microglia by clodronate-containing liposome injection or dexamethasone treatment impairs regenerative neurogenesis,as previously described,as well as injury-induced angiogenesis.In conclusion,we have described regenerative angiogenesis in zebrafish for the first time and have highlighted the role of inflammation in this process.In addition,we have shown that both angiogenesis and neurogenesis are involved in brain repair and that microglia and inflammation-dependent mechanisms activated by Vegf signaling are important contributors to these processes.This study paves the way for a better understanding of the effect of Vegf on microglia and for studies aimed at promoting angiogenesis to improve brain plasticity after brain injury.

Transforming growth factor-beta 1 enhances discharge activity of cortical neurons

Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system.

Florfenicol can inhibit chick growth and lead to immunosuppression

Florfenicol(FLO)is a chemically synthesized broad-spectrum antimicrobial agent of amide alcohols for animals,which is one of the most widely used antimicrobials in livestock,poultry,and aquaculture.With the use of FLo,more and more attention has been paid to its hematopoietic toxicity,immunotoxicity,genotoxicity,and embryotoxicity.In this study,SPF chicks.at the age of 3 d began to drink water with the FLO at a dose of 100 mg L^(-1)for 6 consecutive days,and the growth performance of chicks was monitored,the effect of FLO on immune organs was detected by pathological examination and TdT-mediated dUTP nick-end labeling(TUNEL)apoptosis staining.In order to evaluate the level of organism immunity,the level of Newcastle disease virus antibody in serum was detected by hemagglutination inhibition test,the content of cytokines(IL-1,IL-2,IL-6,TNF-α,IFN-γ)in serum was detected by enzyme linked immunosorbent assay(ELISA),and the transcription of interferon-related genes(IRF-7,2′-5′OAS,Mx1)and cytokine genes(IL-6,TNF-α,IFN-γ)in immune organs were detected by real time fluorescence quantitative PCR.The results showed that the early application of FLO could inhibit the growth and development of chicks,and the body weight and immune organ index of the treatment group were lower than those of the control group.Histopathological examination showed that there was a decrease in the number of lymphocytes in the bursa of Fabricius in the treatment group in the early stage of drug withdrawal,and the results of TUNEL apoptosis staining in the bursa of Fabricius showed that obvious lymphocyte apoptosis occurred in the FLO treatment group.Compared with the control group,the transcription levels of interferon-related genes IRF-7,2′-5′OAS,and cytokine genes IL-6,TNF-αand IFN-γin FLO treatment group decreased to a certain extent,while the transcription level of Mx1 gene had no significant difference at all time points.The level of serum Newcastle disease virus(NDV)antibody and the contents of cytokines IL-1,IL-2 and IFN-γin the FLO treatment group were significantly lower than those in the control group in the early stage of drug withdrawal,but recovered gradually in the later stage.This study showed that FLO has a certain degree of effect on the immune function of chicks,and the results of the study laid the foundation for further research on the mechanism of FLO-induced immunotoxicity.

Activation of adult endogenous neurogenesis by a hyaluronic acid collagen gel containing basic fibroblast growth factor promotes remodeling and functional recovery of the injured cerebral cortex

The presence of endogenous neural stem/progenitor cells in the adult mammalian brain suggests that the central nervous system can be repaired and regenerated after injury.However,whether it is possible to stimulate neurogenesis and reconstruct cortical layers II to VI in non-neurogenic regions,such as the cortex,remains unknown.In this study,we implanted a hyaluronic acid collagen gel loaded with basic fibroblast growth factor into the motor cortex immediately following traumatic injury.Our findings reveal that this gel effectively stimulated the proliferation and migration of endogenous neural stem/progenitor cells,as well as their differentiation into mature and functionally integrated neurons.Importantly,these new neurons reconstructed the architecture of cortical layers II to VI,integrated into the existing neural circuitry,and ultimately led to improved brain function.These findings offer novel insight into potential clinical treatments for traumatic cerebral cortex injuries.

Dynamic intelligent prediction approach for landslide displacement based on biological growth models and CNN-LSTM

Influenced by complex external factors,the displacement-time curve of reservoir landslides demonstrates both short-term and long-term diversity and dynamic complexity.It is difficult for existing methods,including Regression models and Neural network models,to perform multi-characteristic coupled displacement prediction because they fail to consider landslide creep characteristics.This paper integrates the creep characteristics of landslides with non-linear intelligent algorithms and proposes a dynamic intelligent landslide displacement prediction method based on a combination of the Biological Growth model(BG),Convolutional Neural Network(CNN),and Long ShortTerm Memory Network(LSTM).This prediction approach improves three different biological growth models,thereby effectively extracting landslide creep characteristic parameters.Simultaneously,it integrates external factors(rainfall and reservoir water level)to construct an internal and external comprehensive dataset for data augmentation,which is input into the improved CNN-LSTM model.Thereafter,harnessing the robust feature extraction capabilities and spatial translation invariance of CNN,the model autonomously captures short-term local fluctuation characteristics of landslide displacement,and combines LSTM's efficient handling of long-term nonlinear temporal data to improve prediction performance.An evaluation of the Liangshuijing landslide in the Three Gorges Reservoir Area indicates that BG-CNN-LSTM exhibits high prediction accuracy,excellent generalization capabilities when dealing with various types of landslides.The research provides an innovative approach to achieving the whole-process,realtime,high-precision displacement predictions for multicharacteristic coupled landslides.

Effects of biological soil crusts on plant growth and nutrient dynamics in the Minqin oasis-desert ecotone,Northwest China

Biological soil crusts(BSCs)play crucial roles in improving soil fertility and promoting plants settlement and reproduction in arid areas.However,the specific effects of BSCs on growth status and nutrient accumulation of plants are still unclear in different arid areas.This study analyzed the effects of three different BSCs treatments(without crust(WC),intact crust(IC),and broken crust(BC))on the growth,inorganic nutrient absorption,and organic solute synthesis of three typical desert plants(Grubovia dasyphylla(Fisch.&C.A.Mey.)Freitag&G.Kadereit,Nitraria tangutorum Bobrov,and Caragana koraiensis Kom.)in the Minqin desert-oasis ecotone of Northwest China.Results showed that the effects of three BSCs treatments on seed emergence and survival of three plants varied with seed types.The IC treatment significantly hindered the emergence and survival of seeds,while the BC treatment was more conducive to seed emergence and survival of plants.BSCs significantly promoted the growth of three plants,but their effects on plant growth varied at different stages of the growth.Briefly,the growth of G.dasyphylla was affected by BSCs in early stage,but the effects on the growth of G.dasyphylla significantly weakened in the middle and late stages.However,the growth of N.tangutorum and C.koraiensis only showed differences at the middle and late stages,with a significant enhancement in growth.Analysis of variance showed that BSCs,plant species,growth period,and their interactions had significant effects on the biomass and root:shoot ratio of three plants.BSC significantly affected the nutrients absorption and organic solute synthesis in plants.Specifically,BSCs significantly promoted nitrogen(N)absorption in plants and increased plant adaptability in N poor desert ecosystems,but had no significant effects on phosphorus(P)absorption.The effects of BSCs on inorganic nutrient absorption and organic solute synthesis in plants varied significantly among different plant species.The results suggest that BSCs have significant effects on the growth and nutrient accumulation of desert plants,which will provide theoretical basis for exploring the effects of BSCs on desert plant diversity,biodiversity conservation,and ecosystem management measures in arid and semi-arid areas.

Exploring the mechanistic role of epidermal growth factor receptor activation in non-cancer kidney disease

The epidermal growth factor receptor(EGFR)is a transmembrane glycoprotein that plays a crucial role in signal transduction and cellular responses.This review explores the function of EGFR in kidney physiology and its implications for various kidney diseases.EGFR signaling is essential for kidney function and repair mechanisms,and its dysregulation significantly impacts both acute and chronic kidney conditions.The review discusses the normal distribution of EGFR in kidney tubular segments,the mechanism of its activation and inhibition,and the therapeutic potential of EGFR-targeting antagonists and ligands.Additionally,it explores the pathophysiological characteristics observed in rodent models of kidney diseases through pharmacological and genetic inhibition of EGFR,highlighting therapeutic challenges and limitations such as species differences,variability in disease models,and potential adverse effects.Overall,the findings underscore the multifaceted role of EGFR in kidney diseases,influencing inflammation,fibrosis,and tissue injury.This complex involvement suggests that targeting EGFR may be a beneficial therapeutic strategy for managing these conditions,potentially mitigating inflammation and fibrosis while promoting tissue repair.

A vascular endothelial growth factor–loaded chitosan-hyaluronic acid hydrogel scaffold enhances the therapeutic effect of adipose-derived stem cells in the context of stroke

Adipose-derived stem cell,one type of mesenchymal stem cells,is a promising approach in treating ischemia-reperfusion injury caused by occlusion of the middle cerebral artery.However,its application has been limited by the complexities of the ischemic microenvironment.Hydrogel scaffolds,which are composed of hyaluronic acid and chitosan,exhibit excellent biocompatibility and biodegradability,making them promising candidates as cell carriers.Vascular endothelial growth factor is a crucial regulatory factor for stem cells.Both hyaluronic acid and chitosan have the potential to make the microenvironment more hospitable to transplanted stem cells,thereby enhancing the therapeutic effect of mesenchymal stem cell transplantation in the context of stroke.Here,we found that vascular endothelial growth factor significantly improved the activity and paracrine function of adipose-derived stem cells.Subsequently,we developed a chitosan-hyaluronic acid hydrogel scaffold that incorporated vascular endothelial growth factor and first injected the scaffold into an animal model of cerebral ischemiareperfusion injury.When loaded with adipose-derived stem cells,this vascular endothelial growth factor–loaded scaffold markedly reduced neuronal apoptosis caused by oxygen-glucose deprivation/reoxygenation and substantially restored mitochondrial membrane potential and axon morphology.Further in vivo experiments revealed that this vascular endothelial growth factor–loaded hydrogel scaffold facilitated the transplantation of adipose-derived stem cells,leading to a reduction in infarct volume and neuronal apoptosis in a rat model of stroke induced by transient middle cerebral artery occlusion.It also helped maintain mitochondrial integrity and axonal morphology,greatly improving rat motor function and angiogenesis.Therefore,utilizing a hydrogel scaffold loaded with vascular endothelial growth factor as a stem cell delivery system can mitigate the adverse effects of ischemic microenvironment on transplanted stem cells and enhance the therapeutic effect of stem cells in the context of stroke.

Overall survival with frontline vs subsequent anti-epidermal growth factor receptor therapies in unresectable,RAS/BRAF wild-type,leftsided metastatic colorectal cancer

BACKGROUND The combination of anti-epidermal growth factor receptor(EGFR)therapy and chemotherapy is currently a preferred first-line treatment for patients with unre-sectable,RAS and BRAF wild-type,left-sided metastatic colorectal cancer(mCRC).Several studies have also demonstrated the benefit of anti-EGFR therapy in sub-sequent line settings for this patient population.However,direct evidence com-paring the effectiveness of frontline vs subsequent anti-EGFR therapy remains limited,leaving a crucial gap in guiding optimal treatment strategies.AIM To compare overall survival(OS)between frontline and subsequent anti-EGFR treatment in patients with unresectable,RAS and BRAF wild-type,left-sided mCRC.METHODS We retrospectively reviewed the medical records of mCRC patients treated at The King Chulalongkorn Memorial Hospital and Songklanagarind Hospital,Thailand,between January 2013 and April 2023.Patients were classified into two groups based on the sequence of their anti-EGFR treatment.The primary endpoint was OS.RESULTS Among 222 patients with a median follow-up of 29 months,no significant difference in OS was observed between the frontline and subsequent-line groups(HR 1.03,95%CI:0.73-1.46,P=0.878).The median OS was 35.53 months(95%CI:26.59-44.47)for the frontline group and 31.60 months(95%CI:27.83-35.37)for the subsequent-line group.In the subsequent-line group,71 patients(32.4%)who ultimately never received anti-EGFR therapy had a significantly worse median OS of 19.70 months(95%CI:12.87-26.53).CONCLUSION Frontline and subsequent-line anti-EGFR treatments provide comparable OS in unresectable,RAS/BRAF wild-type,left-sided mCRC patients,but early exposure is vital for those unlikely to receive subsequent therapy.

基于FP-growth算法的交通事故数据关联规则挖掘研究

为了探寻多种事故影响因素共同作用下诱发交通事故的某种规律以及各因素间的关系,本文采用FP-growth算法对收集到的交通事故数据进行分析研究,挖掘其中的潜在价值信息,找出事故发生的原因,根据分析结果给相关部门提出建议,帮助城市交通管理者制定更有效的管理措施,以达到降低交通事故发生频率的目的。

A conceptual model of posttraumatic growth of nursing students with a disabled parent

Objectives: To examine a conceptual model of posttraumatic growth (PTG) with the inclusion of family resilience as a mediator,and social support,individual resilience,maternal care,and family members' intimacy after trauma as protective factors.Methods: A cross-sectional questionnaire survey was carried out in a sample of 134 college nursing students who had a parent with a non-congenital disability.The Socio-demographic Information Questionnaire,the Chinese version of Perceived Social Support Scale (PSSS),10-item Connor-Davidson Resilience Scale (CD-RISC10),Parental Bonding Instrument (PBI),Family Resilience Assessment Scale (FRAS) and the Posttraumatic Growth Inventory (PTGI) were used to collect data.Results: Results showed that social support,individual resilience,maternal care,and family members' intimacy after trauma positively predicted family resilience (β=0.41,0.20,0.20,0.22,all P<0.01),respectively,and indirectly predicted PTG through family resilience.Family resilience positively predicted PTG (β =0.25,P < 0.01).Moreover,individual resilience directly positively predicted PTG (β =0.25,P < 0.001).Conclusions: Family resilience could facilitate PTG in nursing students in the face of parental disability.Interventions to promote PTG among college nursing students who have experienced parental disability should consider individual or family resilience-based intervention.

Serial Multiple Mediation of the Relationshipbetween Positive Coping Style and PostTraumatic Growth among Chinese CollegeStudents in the Aftermath of COVID-19

Given the ongoing character of COVID-19, higher-education students encountered multifaceted pressures brought about by thepandemic and had to overcome many difficulties during this period. Accordingly, it is imperative to identify the factors that mayhave protective effects on the social functioning and mental status of college students in the aftermath of COVID-19. This crosssectional study sought to ascertain the internal mechanism of positive coping (PC) styles affecting post-traumatic growth (PTG)and considered the mediating roles of cognitive reappraisal (CR), psychological resilience (PR), and deliberate rumination (DR),which are essential for understanding how and to what extent these factors shaped PTG in the context of the present pandemic. 463Chinese college students recruited via a convenience sampling method completed a set of online self-report measures of PC, PTG,CR, PR and DR. The findings revealed that the abovementioned five variables were positively correlated with each other, and theindependent variable directly predicted the dependent variable. More importantly, two out of three mediators in parallel mediatedthe relationship between PC and PTG, illustrating that more PC adoption was associated with increased PTG through high levels ofPR and DR, respectively. The two significant serial mediating effects also indicated that PC could contribute to CR, which furtherfacilitates either PR or DR and subsequently promotes the development of PTG. Colleges should adopt routine protectivebehaviors in accordance with such evidence to strengthen students’ mental health education and establish scientific methods toboost their psychological well-being. Overall, our results may shed new light on the process of positive adaption and providetheoretical support for targeted crisis intervention during the late phase of the pandemic.

Comparison of posttraumatic growth and posttraumatic stress of nurses with physicians and medical students after caring of COVID‑19 patients

Objectives:The present study compared the prevalence and psychosocial factors affecting posttraumatic growth(PTG),posttraumatic stress disorder(PTSD),and psychological distress in nurses,physicians,and medical students.Materials and Methods:In a cross‑sectional study,three groups of medical staff including nurses(n=57),physicians(n=40),and medical students(n=34)who were responsible for the care/treatment of COVID‑19 patients admitted to a general hospital for 4 months responded to Posttraumatic Growth Inventory,Brief Symptom Inventory‑18,Resilience Questionnaire,PTSD Screen,and Social Capital‑Integrated Questionnaire.Results:After the exposure of medical staff to at least 4 months of treatment/care of COVID‑19 patients,PTG prevalence was higher than PTSD(38.2%vs.14.6%),but they experienced some degrees of psychological distress(65.5%).The nurses had 8.33(confidence interval[CI]:2.5–26.7)times higher PTG rate than medical students(P<0.001).Physicists also experienced 5.00(CI:1.4–26.7)times higher PTG than medical students(P<0.001).PTG was aided by age,married status,strong resilience,and high social capital,but gender had no influence.Resilience played an important protective role to prevent the incidence of psychological distress in nurses,medical students,and physicians.Conclusion:Despite the fact that the PTSD and psychological distress were same in the three groups of medical staff,the nurses had a greater rate of PTG than physicians and medical students.

基于FP-growth的老年行人交通事故损伤致因研究

为研究老年行人交通事故相关因素及其对损伤程度的影响,以中国交通事故深度调查数据库中2013—2023年710起机动车-老年行人事故为分析对象,利用FP-growth算法挖掘出4类影响因素28个类型变量共5594项关联规则。研究结果表明:行人年龄、碰撞速度、事故时间段及事故地点是影响老年行人事故死亡率的显著因素。特别是,行人年龄和碰撞速度对死亡率有显著影响,随着碰撞速度的增加,死亡率显著上升;60岁及以上老年行人年龄每增加1岁,其死亡率提升0.037倍。此外,事故发生在夜间、郊区或村庄的死亡率更高。研究结果可为提高老年行人交通安全,制定相关安全措施提供一定参考。

Structural Engineering of Hierarchical Magnetic/Carbon Nanocomposites via In Situ Growth for High-Efficient Electromagnetic Wave Absorption

Materials exhibiting high-performance electromagnetic wave absorption have garnered considerable scientific and technological attention,yet encounter significant challenges.Developing new materials and innovative structural design concepts is crucial for expanding the application field of electromagnetic wave absorption.Particularly,hierarchical structure engineering has emerged as a promising approach to enhance the physical and chemical properties of materials,providing immense potential for creating versatile electromagnetic wave absorption materials.Herein,an exceptional multi-dimensional hierarchical structure was meticulously devised,unleashing the full microwave attenuation capabilities through in situ growth,selfreduction,and multi-heterogeneous interface integration.The hierarchical structure features a three-dimensional carbon framework,where magnetic nanoparticles grow in situ on the carbon skeleton,creating a necklace-like structure.Furthermore,magnetic nanosheets assemble within this framework.Enhanced impedance matching was achieved by precisely adjusting component proportions,and intelligent integration of diverse interfaces bolstered dielectric polarization.The obtain Fe_(3)O_(4)-Fe nanoparticles/carbon nanofibers/Al-Fe_(3)O_(4)-Fe nanosheets composites demonstrated outstanding performance with a minimum reflection loss(RLmin)value of−59.3 dB and an effective absorption bandwidth(RL≤−10 dB)extending up to 5.6 GHz at 2.2 mm.These notable accomplishments offer fresh insights into the precision design of high-efficient electromagnetic wave absorption materials.

基于改进FP-growth算法的食品风险因素关联分析方法

为解决传统食品安全监督抽检“随机抽”模式存在的抽检决策主观性强、靶向性不高的问题,本研究提出一种基于改进Frequent Pattern-growth(FP-growth)算法的食品风险因素关联分析方法。首先,采用熵权法分别对食品种类的风险指标进行权重分配,以计算出不同食品种类的风险指数。其次,以风险指数为特征,基于小批量K均值算法(MiniBatchKmeans)进行风险聚类,得到食品的风险等级。最后,采用带约束的改进FP-growth算法进行食品风险因素关联规则挖掘,挖掘食品风险等级与食品种类、时间、地域属性信息之间的关联关系,并对挖掘出的结果进行关联分析,从而为精准靶向引导抽检决策提供指导。本研究依托2019年中国某些地区的食品抽检数据进行分析,对其进行指标赋权,计算风险指数;后经过风险聚类为低风险、中风险和高风险;最后,将数据导入改进FPgrowth算法,得到食品风险因素关联规则。通过对比实验得到结果:对于17214条抽检数据,本研究提出的改进FP-growth算法相较于Apriori算法运行时间短;相较于传统FP-growth算法,删除了无效规则,提高了对食品风险因素关联规则的分析效率,从而为食品监管部门抽检工作提供了准确、高效的决策依据。

Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei

Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted.

Construction of Guiding System for Growth and Development of College Students under the Student-oriented Concept

The student-oriented concept is a kind of people orientation. It emphasizes respect and support for students. It is student-centered,and is for all students. At the school level,the guiding principles of student orientation and respecting teachers and teaching must be adhered to,and corresponding reforms in the school's system,policies and environment needs to be carried out. At the university teacher level,the concept of student orientation must be adhered to in teaching,and it is regarded as the guiding concept of teaching and education and is implemented in classroom teaching and practical teaching. At the level of college administrator,the concept of student orientation must be adhered in the course of daily management and service to do better management,service and education work. In order to better implement the student-oriented concept and promote the growth and development of college students,we needs to build a mentor team for college students' growth based on political workers,establish a team of academic tutors for college students based on professional teachers and build a platform for cooperation between schools and enterprises. The innovative training mode can promote students to grow into talents.

GbLMI1 over-expression improves cotton aboveground vegetative growth

Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have shown that LMI1(LATE MERISTEM IDENTITY1)is the main gene regulating leaf shape.In this study,the LMI1 gene was inserted into the 35S promoter expression vector,and cotton plants overexpressing LMI1(OE)were obtained through genetic transformation.Statistical analysis of the biological traits of the T_(1) and T_(2) populations showed that compared to the wild type(WT),OE plants had significantly larger leaves,thicker stems and significantly greater dry weight.Furthermore,plant sections of the main vein and petiole showed that the numbers of cells in those tissues of OE plants were significantly greater.In addition,RNA-seq analysis revealed the differential expression of genes related to gibberellin synthesis and NAC gene family(genes containing the NAC domain)between the OE and WT plants,suggesting that LMI1 is involved in secondary wall formation and cell proliferation,which promotes stem thickening.Moreover,Gene Ontology(GO)analysis revealed enrichment in the terms of calcium ion binding,and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis showed enrichment in the terms of fatty acid degradation,phosphatidylinositol signal transduction system,and c AMP(cyclic adenosine monophosphate)signal pathway.These results suggested that LMI1 OE plants are responsive to gibberellin hormone signals,and have altered messenger signals(c AMP,Ca^(2+))which amplify this function,to promote stronger aboveground vegetative growth.This study found the LMI1 greatly increased the vegetative growth in cotton,which is the basic requirement for higher yield.