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A new horizon for neuroscience:terahertz biotechnology in brain research
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作者 Zhengping Pu yu wu +2 位作者 Zhongjie Zhu Hongwei Zhao Donghong Cui 《Neural Regeneration Research》 SCIE CAS 2025年第2期309-325,共17页
Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biot... Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biotechnology and its applications in the field of neuropsychiatry.Available evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin deficit.In vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric diseases.Although the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic applications.However,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical applications.This review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages. 展开更多
关键词 biological effect brain NEURON NEUROPSYCHIATRY NEUROSCIENCE non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology
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Phase II Clinical Study of Three-Dimensional Printed Coplanar Template Combined with CT-Guided Percutaneous Core Needle Biopsy of Pulmonary Nodules in Elderly Patients
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作者 Wangti Xie yu wu +11 位作者 Xiaoshan Cheng Jianbing Hu Fang Wen Jia Xiao Pan Luo yuqi Su Xiang Yao Jianlong Fang Grong Dan Xianggan Huang Dunqian Liu Jie Weng 《Journal of Biosciences and Medicines》 2024年第7期325-336,共12页
Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lu... Background: As the population age structure gradually ages, more and more elderly people were found to have pulmonary nodules during physical examinations. Most elderly people had underlying diseases such as heart, lung, brain and blood vessels and cannot tolerate surgery. Computed tomography (CT)-guided percutaneous core needle biopsy (CNB) was the first choice for pathological diagnosis and subsequent targeted drugs, immune drugs or ablation treatment. CT-guided percutaneous CNB requires clinicians with rich CNB experience to ensure high CNB accuracy, but it was easy to cause complications such as pneumothorax and hemorrhage. Three-dimensional (3D) printing coplanar template (PCT) combined with CT-guided percutaneous pulmonary CNB biopsy has been used in clinical practice, but there was no prospective, randomized controlled study. Methods: Elderly patients with lung nodules admitted to the Department of Oncology of our hospital from January 2019 to January 2023 were selected. A total of 225 elderly patients were screened, and 30 patients were included after screening. They were randomly divided into experimental group (Group A: 30 cases) and control group (Group B: 30 cases). Group A was given 3D-PCT combined with CT-guided percutaneous pulmonary CNB biopsy, Group B underwent CT-guided percutaneous pulmonary CNB. The primary outcome measure of this study was the accuracy of diagnostic CNB, and the secondary outcome measures were CNB time, number of CNB needles, number of pathological tissues and complications. Results: The diagnostic accuracy of group A and group B was 96.67% and 76.67%, respectively (P = 0.026). There were statistical differences between group A and group B in average CNB time (P = 0.001), number of CNB (1 vs more than 1, P = 0.029), and pathological tissue obtained by CNB (3 vs 1, P = 0.040). There was no statistical difference in the incidence of pneumothorax and hemorrhage between the two groups (P > 0.05). Conclusions: 3D-PCT combined with CT-guided percutaneous CNB can improve the puncture accuracy of elderly patients, shorten the puncture time, reduce the number of punctures, and increase the amount of puncture pathological tissue, without increasing pneumothorax and hemorrhage complications. We look forward to verifying this in a phase III randomized controlled clinical study. . 展开更多
关键词 Pulmonary Nodules Elderly patients Three-Dimensional (3D) Printed Coplanar Template (PCT) Core Needle Biopsy (CNB) Computed Tomography (CT)
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Flexible bidirectional pulse charging regulation achieving long-life lithium-ion batteries 被引量:1
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作者 Xiaodong Xu Shengjin Tang +9 位作者 Xuebing Han Languang Lu yudi Qin Jiuyu Du yu wu Yalun Li Chuanqiang yu Xiaoyan Sun Xuning Feng Minggao Ouyang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第9期59-71,共13页
Typical application scenarios,such as vehicle to grid(V2G)and frequency regulation,have imposed significant long-life demands on lithium-ion batteries.Herein,we propose an advanced battery life-extension method employ... Typical application scenarios,such as vehicle to grid(V2G)and frequency regulation,have imposed significant long-life demands on lithium-ion batteries.Herein,we propose an advanced battery life-extension method employing bidirectional pulse charging(BPC)strategy.Unlike traditional constant current charging methods,BPC strategy not only achieves comparable charging speeds but also facilitates V2G frequency regulation simultaneously.It significantly enhances battery cycle ampere-hour throughput and demonstrates remarkable life extension capabilities.For this interesting conclusion,adopting model identification and postmortem characterization to reveal the life regulation mechanism of BPC:it mitigates battery capacity loss attributed to loss of lithium-ion inventory(LLI)in graphite anodes by intermittently regulating the overall battery voltage and anode potential using a negative charging current.Then,from the perspective of internal side reaction,the life extension mechanism is further revealed as inhibition of solid electrolyte interphase(SEI)and lithium dendrite growth by regulating voltage with a bidirectional pulse current,and a semi-empirical life degradation model combining SEI and lithium dendrite growth is developed for BPC scenarios health management,the model parameters are identified by genetic algorithm with the life simulation exhibiting an accuracy exceeding 99%.This finding indicates that under typical rate conditions,adaptable BPC strategies can extend the service life of LFP battery by approximately 123%.Consequently,the developed advanced BPC strategy offers innovative perspectives and insights for the development of long-life battery applications in the future. 展开更多
关键词 Lithium-ion battery Long-life regulation Bidirectional pulse charging Mechanism identification
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西藏昂仁县树龄超过300年和1000年的古树树木年轮学论证
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作者 旦增欧珠 喻武 +1 位作者 郑嘉诚 张齐兵 《西藏科技》 2024年第7期14-18,39,共6页
西藏西部地区由于生境严酷,很难发现树龄特大的古树。笔者在2023年对昂仁县的古树资源调查中,发现了两棵树龄特大的大果圆柏(Juiperus tibetica Kom.)古树。一棵古树位于达局乡甘丹塔空寺内,采集到的树芯样本接近树干髓心,通过树木年轮... 西藏西部地区由于生境严酷,很难发现树龄特大的古树。笔者在2023年对昂仁县的古树资源调查中,发现了两棵树龄特大的大果圆柏(Juiperus tibetica Kom.)古树。一棵古树位于达局乡甘丹塔空寺内,采集到的树芯样本接近树干髓心,通过树木年轮学方法鉴定其树龄约为306年(起始于1716年)。另一棵古树位于多白乡谢村,其胸围高达8.5米,仅采集到12厘米的树芯样本上有216个年轮,推算这棵古树的树龄超过了千年。两株古树的树木年轮数据既反映了区域气候变化信号,也反映了局地小生境和人们对古树的保护信号,同时显示了古树目前生长处于健康状态。研究结果丰富了昂仁县古树本底资源信息,对认识西藏西部地区古树文化、生态、气候、科研和社会价值具有重要意义。 展开更多
关键词 古树资源 千年古树 古树生长历史 大果圆柏
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Flotation separation of scheelite from calcite using luteolin as a novel depressant
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作者 Xiaokang Li Ying Zhang +3 位作者 Haiyang He yu wu Danyu wu Zhenhao Guan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第3期462-472,共11页
This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)system.The suitability of LUT as a calcite depressant is confirmed through mic... This paper proposes luteolin(LUT)as a novel depressant for the flotation-based separation of scheelite and calcite in a sodium oleate(NaOL)system.The suitability of LUT as a calcite depressant is confirmed through micro-flotation testing.At pH=9,with LUT concentration of 50 mg·L^(-1) and NaOL concentration of 50 mg·L^(-1),scheelite recovery reaches 80.3%.Calcite,on the other hand,exhibits a recovery rate of 17.6%,indicating a significant difference in floatability between the two minerals.Subsequently,the surface modifica-tions of scheelite and calcite following LUT treatment are characterized using adsorption capacity testing,Zeta potential analysis,Fourier transform infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy(XPS),and atomic force microscopy(AFM).The study in-vestigates the selective depressant mechanism of LUT on calcite.Adsorption capacity testing and Zeta potential analysis demonstrate sub-stantial absorption of LUT on the surface of calcite,impeding the further adsorption of sodium oleate,while its impact on scheelite is min-imal.FT-IR and XPS analyses reveal the selective adsorption of LUT onto the surface of calcite,forming strong chemisorption bonds between the hydroxyl group and calcium ions present.AFM directly illustrates the distinct adsorption densities of LUT on the two miner-al types.Consequently,LUT can effectively serve as a depressant for calcite,enabling the successful separation of scheelite and calcite. 展开更多
关键词 SCHEELITE CALCITE LUTEOLIN FLOTATION depressant SEPARATION
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NbN quantum dots anchored hollow carbon nanorods as efficient polysulfide immobilizer and lithium stabilizer for Li-S full batteries
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作者 Fei Ma Zhuo Chen +9 位作者 Katam Srinivas Ziheng Zhang yu wu Dawei Liu Hesheng yu yue Wang Xinsheng Li Ming-qiang Zhu Qi wu yuanfu Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期260-271,I0007,共13页
The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispers... The shuttle effect of lithium polysulfides(LiPSs)and uncontrollable lithium dendrite growth seriously hinder the practical application of lithium-sulfur(Li-S)batteries.To simultaneously address such issues,monodispersed Nb N quantum dots anchored on nitrogen-doped hollow carbon nanorods(NbN@NHCR)are elaborately developed as efficient Li PSs immobilizer and Li stabilizer for high-performance Li-S full batteries.Density functional theory(DFT)calculations and experimental characterizations demonstrate that the sulfiphilic and lithiophilic NbN@NHCR hybrid can not only efficiently immobilize the soluble Li PSs and facilitate diffusion-conversion kinetics for alleviating the shuttling effect,but also homogenize the distribution of Li+ions and regulate uniform Li deposition for suppressing Li-dendrite growth.As a result,the assembled Li-S full batteries(NbN@NHCR-S||Nb N@NHCR-Li)deliver excellent long-term cycling stability with a low decay rate of 0.031%per cycle over 1000 cycles at high rate of 2 C.Even at a high S loading of 5.8 mg cm^(-2)and a low electrolyte/sulfur ratio of 5.2μL mg^(-1),a large areal capacity of 6.2 mA h cm^(-2)can be achieved in Li-S pouch cell at 0.1 C.This study provides a new perspective via designing a dual-functional sulfiphilic and lithiophilic hybrid to address serious issues of the shuttle effect of S cathode and dendrite growth of Li anode. 展开更多
关键词 Dual-functional host NbN quantum dots Shuttle effect Dendrite-free Li anode Li-S full batteries
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Sinensetin protects against periodontitis through binding to Bach1 enhancing its ubiquitination degradation and improving oxidative stress
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作者 Zhiyao yuan Junjie Li +6 位作者 Fuyu Xiao yu wu Zhiting Zhang Jiahong Shi Jun Qian Xudong wu Fuhua Yan 《International Journal of Oral Science》 SCIE CAS CSCD 2024年第3期553-562,共10页
Periodontitis is a chronic inflammatory and immune reactive disease induced by the subgingival biofilm.The therapeutic effect for susceptible patients is often unsatisfactory due to excessive inflammatory response and... Periodontitis is a chronic inflammatory and immune reactive disease induced by the subgingival biofilm.The therapeutic effect for susceptible patients is often unsatisfactory due to excessive inflammatory response and oxidative stress.Sinensetin(Sin)is a nature polymethoxylated flavonoid with anti-inflammatory and antioxidant activities.Our study aimed to explore the beneficial effect of Sin on periodontitis and the specific molecular mechanisms.We found that Sin attenuated oxidative stress and inflammatory levels of periodontal ligament cells(PDLCs)under inflammatory conditions.Administered Sin to rats with ligation-induced periodontitis models exhibited a protective effect against periodontitis in vivo.By molecular docking,we identified Bach1 as a strong binding target of Sin,and this binding was further verified by cellular thermal displacement assay and immunofluorescence assays.Chromatin immunoprecipitation-quantitative polymerase chain reaction results also revealed that Sin obstructed the binding of Bach1 to the HMOX1 promoter,subsequently upregulating the expression of the key antioxidant factor HO-1.Further functional experiments with Bach1 knocked down and overexpressed verified Bach1 as a key target for Sin to exert its antioxidant effects.Additionally,we demonstrated that Sin prompted the reduction of Bach1 by potentiating the ubiquitination degradation of Bach1,thereby inducing HO-1 expression and inhibiting oxidative stress.Overall,Sin could be a promising drug candidate for the treatment of periodontitis by targeting binding to Bach1. 展开更多
关键词 Bach1 period PROMPT
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Clinical Effect Observation of Constructing PERMA Model in Psychological Intervention for Patients with Chronic Cancer Pain
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作者 yu-Feng Ren Dong-Li Ji +2 位作者 yu wu Ru-Qin Ben Hai-Xia Wei 《Psycho-Oncologie》 SCIE 2024年第4期329-336,共8页
Background:The constructing PERMA model in psychological intervention was applied to patients with chronic cancer pain to provide data reference for reducing pain,fear of cancer recurrence,and improving the level of p... Background:The constructing PERMA model in psychological intervention was applied to patients with chronic cancer pain to provide data reference for reducing pain,fear of cancer recurrence,and improving the level of psychological capital.Aim:To explore the clinical effects of constructing PERMA model in psychological intervention for patients with chronic cancer pain.Methods:A total of 98 patients with chronic cancer pain admitted to our hospital from March 2021 to March 2023 were randomly divided into two groups,49 cases in each group.The control group received routine intervention,while the research group constructed PERMA model based on the routine intervention for psychological intervention.The pain severity,fear of cancer recurrence,psychological capital and quality of life before and after intervention were compared between the two groups.Results:After two months of intervention,the pain in the research group was milder than that in the control group(p<0.05).The scores and total scores of all dimensions of fear of cancer recurrence in the research group were lower than those in the control group(p<0.05).The scores and total scores of each dimension of psychological capital in the research group were higher than those in the control group(p<0.05).The scores of all dimensions of quality of life in the research group were higher than those in the control group(p<0.05).Conclusion:The PERMA model constructed in psychological interventions for patients with chronic cancer pain can assist analgesic medications to reduce pain and alleviate the fear of cancer recurrence,increase the level of psychological capital,and thus improve quality of life. 展开更多
关键词 Chronic cancer pain psychological intervention PERMA model degree of pain fear of cancer recurrence psychological capital quality of life
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Laryngeal leiomyoma:A case report and review of literature
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作者 yu wu Jing-Man Li +1 位作者 Tian-Jiao Zhang Xin Wang 《World Journal of Clinical Cases》 SCIE 2024年第18期3529-3533,共5页
BACKGROUND Leiomyomas(LMs)are mesenchymal tumors that arise from smooth muscle cells.LMs most commonly arise in organs with an abundance of smooth muscle such as the uterus and gastrointestinal tract.Conversely,LMs ar... BACKGROUND Leiomyomas(LMs)are mesenchymal tumors that arise from smooth muscle cells.LMs most commonly arise in organs with an abundance of smooth muscle such as the uterus and gastrointestinal tract.Conversely,LMs are rarely detected in the head and neck region.In this study,we report a rare case of laryngeal LM(LLM)and summarized the clinical characteristics of reported LLMs to help clinicians better understand this rare disease and improve its diagnosis,treatment,and postoperative course.CASE SUMMARY A 49-year-old man was admitted to our ENT outpatient clinic with a chief complaint of pharynx discomfort for 2 months.Laryngoscopy performed under topical anesthesia revealed a solitary,pink mass at the tubercle of epiglottis.Surgery via laryngeal endoscopy was performed under general anesthesia,and the lesion was excised easily.Positive immunohistochemical staining for desmin and smooth-muscle actin indicated a smooth muscle origin and the diagnosis was laryngeal leiomyoma.After surgery,the patient’s condition was stable,and he was discharged 2 d after surgery.During the 1-year postoperative period,the patient’s condition remained stable without evidence of recurrence.CONCLUSION Surgical resection is the preferred treatment for LLMs,its early diagnosis and differential diagnosis have important clinical significance. 展开更多
关键词 LEIOMYOMA LARYNX Smooth tumor Endoscopic surgery Case report
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Construction of prognostic markers for gastric cancer and comprehensive analysis of pyroptosis-related long non-coding RNAs
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作者 yu Wang Di Li +2 位作者 Jing Xun yu wu Hong-Lei Wang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2281-2295,共15页
BACKGROUND China's most frequent malignancy is gastric cancer(GC),which has a very poor survival rate,and the survival rate for patients with advanced GC is dismal.Pyroptosis has been connected to the genesis and ... BACKGROUND China's most frequent malignancy is gastric cancer(GC),which has a very poor survival rate,and the survival rate for patients with advanced GC is dismal.Pyroptosis has been connected to the genesis and development of cancer.The function of pyroptosis-related long non-coding RNAs(PRLs)in GC,on the other hand,remains uncertain.AIM To explore the construction and comprehensive analysis of the prognostic characteristics of long non-coding RNA(lncRNA)related to pyroptosis in GC patients.METHODS The TCGA database provided us with 352 stomach adenocarcinoma samples,and we obtained 28 pyroptotic genes from the Reactome database.We examined the correlation between lncRNAs and pyroptosis using the Pearson correlation coefficient.Prognosis-related PRLs were identified through univariate Cox analysis.A predictive signature was constructed using stepwise Cox regression analysis,and its reliability and independence were assessed.To facilitate clinical application,a nomogram was created based on this signature.we analyzed differences in immune cell infiltration,immune function,and checkpoints between the high-risk group(HRG)and low-risk group(LRG).RESULTS Five hundred and twenty-three PRLs were screened from all lncRNAs(absolute correlation coefficient>0.4,P<0.05).Nine PRLs were included in the risk prediction signature that was created through stepwise Cox regression analysis.We determined the risk score for GC patients and employed the median value as the dividing line between HRG and LRG.The ability of the risk signature to predict the overall survival(OS)of GC is demonstrated by the Kaplan-Meier analysis,risk curve,receiver operating characteristic curve,and decision curve analysis curve.The risk signature was shown to be an independent prognostic factor for OS in both univariate and multivariate Cox regression analyses.HRG showed a more efficient local immune response or modulation compared to LRG,as indicated by the predicted signal pathway analysis and examination of immune cell infiltration,function,and checkpoints(P<0.05).CONCLUSION In general,we have created a brand-new prognostic signature using PRLs,which may provide ideas for immunotherapy in patients with GC. 展开更多
关键词 Gastric cancer PYROPTOSIS PROGNOSIS Immune checkpoint Long non-coding RNA Immune cell infiltrating
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西格列汀对局灶性脑缺血再灌注小鼠血-脑脊液屏障通透性的影响及抗凋亡作用
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作者 康宁 解燕昭 +2 位作者 石源源 虞武 杨梅柳 《脑与神经疾病杂志》 CAS 2024年第11期661-666,共6页
目的研究西格列汀(SIT)在非糖尿病的小鼠脑缺血再灌注(I/R)时的神经保护作用。方法采用大脑中动脉栓塞(MCAO)模型,脑缺血60 min后实施再灌注。SIT按低剂量(40 mg·kg^(-1))、高剂量(80 mg·kg^(-1))在手术前口服给药3d,术后再... 目的研究西格列汀(SIT)在非糖尿病的小鼠脑缺血再灌注(I/R)时的神经保护作用。方法采用大脑中动脉栓塞(MCAO)模型,脑缺血60 min后实施再灌注。SIT按低剂量(40 mg·kg^(-1))、高剂量(80 mg·kg^(-1))在手术前口服给药3d,术后再次给药。术后24 h检测小鼠神经功能、梗死体积和脑水肿,通过Western blot评估Bcl-2和Akt的蛋白表达,RT-qPCR评估Bax和Bcl-2的转录水平。SIT对血-脑脊液屏障(BCFB)通透性的影响通过伊文思蓝渗出和Claudin-5的蛋白表达来测量。结果本研究结果表明,SIT可减轻CD-1小鼠大脑中动脉栓塞再灌注24h后的肢体功能障碍,减少脑梗死体积,减轻脑水肿。SIT显著增加Bcl-2和磷酸化Akt的蛋白表达水平,下调Bax、上调Bcl-2的基因表达。减少小鼠脑组织伊文思蓝渗出并增加Claudin-5的蛋白表达水平(^(均)P<0.05)。结论SIT在非糖尿病小鼠的脑I/R急性期,降低神经功能缺损评分、减少脑梗死体积、保护BCFB,具有脑保护作用,机制可能与抗凋亡有关。这些发现为急性缺血性脑血管病的治疗提供新的策略。 展开更多
关键词 急性局灶性脑缺血再灌注损伤 西格列汀 抗凋亡通路 血-脑脊液屏障
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西藏色季拉山土壤物理性质垂直地带性 被引量:32
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作者 万丹 梁博 +2 位作者 聂晓刚 喻武 张博 《生态学报》 CAS CSCD 北大核心 2018年第3期1065-1074,共10页
以色季拉山为代表的藏东南高原山地的水土流失已成为区域生态环境的重要问题。对色季拉山不同海拔梯度土壤物理性质进行分析,结果表明:(1)除海拔3600、4200m外,土壤容重随土层深度增加而增大;总孔隙度、毛管孔隙度随土层深度增加而减小... 以色季拉山为代表的藏东南高原山地的水土流失已成为区域生态环境的重要问题。对色季拉山不同海拔梯度土壤物理性质进行分析,结果表明:(1)除海拔3600、4200m外,土壤容重随土层深度增加而增大;总孔隙度、毛管孔隙度随土层深度增加而减小;非毛管孔隙度随土层变化无明显规律;饱和含水率、毛管含水率、田间持水率均随土层深度增加而减小。(2)不同海拔梯度,土壤容重总均值、总孔隙度、毛管孔隙度和非毛管孔隙度变化范围分别为:0.58—1.10g/cm^3、57.00%—72.47%、53.33%—67.59%和3.20%—4.87%。饱和含水率、毛管含水率、渗透性具有相同规律,均为3800、3400m处最大,3200m和3600m处最小,4000—4600m居中,田间持水率随海拔梯度变化呈M型波动性趋势。(3)土壤物理性质具有较强的空间异质性,各指标间有明显的空间自相关现象。土壤物理性质各指标在不同土层和海拔间有较明显的差异性,人为干扰也是导致土壤物理性质空间异质性的重要原因。(4)总体上,色季拉山表层土壤(0—10cm)物理结构优于深层次(>10—30cm)土壤;3200m和3600m处最差,4000—4600m居中,3400—3800m最佳。研究结果提示,以色季拉山为代表的藏东南原始森林地带,土壤结构脆弱,为保持水土,应防止旅游和森林生产经营的过度开发。 展开更多
关键词 色季拉山 土壤物理性质 海拔梯度 水土保持
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喜马拉雅山脉南麓典型林地对土壤理化性质及可蚀性K值影响 被引量:17
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作者 梁博 聂晓刚 +3 位作者 万丹 喻武 孙启武 赵薇 《土壤学报》 CAS CSCD 北大核心 2018年第6期1377-1388,共12页
探讨喜马拉雅山脉南麓典型林地土壤结构稳定性及可蚀性K值强弱与分布特征,为区域生态保护提供科学理论及数据基础。选取落叶常绿混交林、针阔混交林、常绿阔叶林三种林分,采集0~20cm土壤,测定团聚体、团聚体破坏率、颗粒组成及其有机质... 探讨喜马拉雅山脉南麓典型林地土壤结构稳定性及可蚀性K值强弱与分布特征,为区域生态保护提供科学理论及数据基础。选取落叶常绿混交林、针阔混交林、常绿阔叶林三种林分,采集0~20cm土壤,测定团聚体、团聚体破坏率、颗粒组成及其有机质,以EPIC模型计算K值。结果表明:(1)不同林地土壤各理化指标具有差异,湿筛及干筛条件下团聚体以>0.25 mm为主;团聚体破坏率在10.16%~24.74%间;颗粒组成以粉砂粒为主,黏粒仅占0.51%~3.02%。有机质在92.53~133.79g·kg-1间;(2)研究区土壤K值在0.1862~0.3430间,均值为0.2635,K值总体较高;(3)经相关分析,K值与黏粒、有机质含量及团聚体破坏率呈正相关,与粉粒呈极显著正相关,与砂粒呈极显著负相关,一定程度,团聚体破坏率可评价土壤可蚀性。 展开更多
关键词 喜马拉雅 土壤可蚀性K值 林地 EPIC模型
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土地利用方式对雅江中游土壤理化性质及颗粒分形特征的影响 被引量:22
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作者 梁博 林田苗 +4 位作者 任德智 聂晓刚 万丹 喻武 赵薇 《土壤》 CAS CSCD 北大核心 2018年第3期613-621,共9页
采取野外调查和室内试验相结合方法,分析了雅江中游4种土地利用方式基本理化性质,并运用土壤颗粒体积分形维数模型研究了不同土地利用方式土壤颗粒分形特征及与土壤粒径、性状关系。结果表明:(1)不同土地利用方式0~30 cm土壤理化性质差... 采取野外调查和室内试验相结合方法,分析了雅江中游4种土地利用方式基本理化性质,并运用土壤颗粒体积分形维数模型研究了不同土地利用方式土壤颗粒分形特征及与土壤粒径、性状关系。结果表明:(1)不同土地利用方式0~30 cm土壤理化性质差异显著(P<0.05),土壤容重表现为稀疏灌丛>农耕地>荒草地>人工林地,随着土壤层次增加,土壤容重呈增大趋势。总孔隙度、毛管孔隙度、饱和持水率、毛管持水率均与容重规律相反;(2)4种土地利用方式主要以粉粒、砂粒为主,黏粒含量仅占到0.36%~4.27%,土壤质地偏砂性;(3)0~30 cm土壤颗粒体积分形维数平均值的顺序为:农耕地>荒草地>人工林地>稀疏灌丛。人工林地具有较好的土壤结构,相对疏松、通透性好。而稀疏灌丛受到砾石影响,分形维数最小,但在保水保肥能力上最弱;(4)土壤颗粒体积分形维数与砂粒体积百分含量呈极显著负相关(r=–0.873,P<0.01);与粉粒体积百分含量呈极显著正相关(r=0.860,P<0.01);与黏粒体积百分含量呈极显著正相关(r=0.913,P<0.01)。这表明,一定程度上,研究区分形维数可作为评估水土流失的指标;(5)土壤颗粒体积分形维数与各土壤单一物理性质具有不同程度相关性,其中与总孔隙度、毛管孔隙度、饱和含水量、毛管含水量均为正相关关系,而与容重、有机质呈负相关关系。 展开更多
关键词 土地利用方式 土壤理化性质 体积分形维数 土壤颗粒
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Vis-NIR光谱快速估测土壤可侵蚀性因子可行性分析 被引量:6
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作者 喻武 贾晓琳 +2 位作者 陈颂超 周炼清 史舟 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2018年第4期1076-1081,共6页
土壤侵蚀降低土地生产力,导致土壤环境恶化,其中水力侵蚀是土壤侵蚀中最主要的一种形式。土壤可侵蚀性K值是评价土壤被降雨侵蚀难易程度的一项重要指标。使用河南、福建和浙江三省研磨干样可见-近红外(Vis-NIR)漫反射光谱数据,将其转换... 土壤侵蚀降低土地生产力,导致土壤环境恶化,其中水力侵蚀是土壤侵蚀中最主要的一种形式。土壤可侵蚀性K值是评价土壤被降雨侵蚀难易程度的一项重要指标。使用河南、福建和浙江三省研磨干样可见-近红外(Vis-NIR)漫反射光谱数据,将其转换为吸收率后进行Savitzky-Golay(SG)平滑去噪;对土壤有机质(SOM)和机械组成进行精准预测后,分别采用EPIC和RUSLE2模型估算K值,并对预测精度进行比较分析,所得结论如下:(1)建立土壤有机质和机械组成高光谱最佳预测模型,土壤质地(砂粒、粉粒和黏粒)预测采用支持向量机(SVM)模型,SOM预测采用局部加权回归(LWR)模型,模型四分位相对预测误差(RPIQ)为2.27,3.17,2.18和3.44;(2)通过土壤质地估算的土壤渗透性等级分类效果较好,Kappa系数为0.62,同时估测的土壤质地类型与实测土壤质地类型分布特征相近,质地主要类型均是粉黏土、砂黏壤土、壤土、壤砂土和砂壤土;(3)EPIC和RUSLE2两种模型均具有较为精确的估测能力,EPIC模型预测精度更高,均方根误差(RMSEP)为0.006 6(t·ha·h)/(ha·MJ·mm),RPIQ达1.58,而RUSLE2模型精度相对较低(其中RPIQ为1.43),因此推荐使用EPIC模型结合Vis-NIR光谱技术估测土壤可侵蚀性K值。本研究为今后快速准确预测K值提供思路,并为大面积监测土壤侵蚀提供辅助手段。 展开更多
关键词 土壤可侵蚀性K值 EPIC RUSLE2
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Research on PolSAR Image Classification Method Based on Vision Transformer Considering Local Information
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作者 Mingxia Zhang Aichun Wang +2 位作者 Xiaozheng Du Xinmeng Wang yu wu 《Journal of Computer and Communications》 2024年第9期22-38,共17页
In response to the problem of inadequate utilization of local information in PolSAR image classification using Vision Transformer in existing studies, this paper proposes a Vision Transformer method considering local ... In response to the problem of inadequate utilization of local information in PolSAR image classification using Vision Transformer in existing studies, this paper proposes a Vision Transformer method considering local information, LIViT. The method replaces image patch sequence with polarimetric feature sequence in the feature embedding, and uses convolution for mapping to preserve image spatial detail information. On the other hand, the addition of the wavelet transform branch enables the network to pay more attention to the shape and edge information of the feature target and improves the extraction of local edge information. The results in Wuhan, China and Flevoland, Netherlands show that considering local information when using Vision Transformer for PolSAR image classification effectively improves the image classification accuracy and shows better advantages in PolSAR image classification. 展开更多
关键词 Vision Transformer POLSAR Image Classification LIViT
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西藏米拉山土壤团聚体垂直地带性特征 被引量:3
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作者 喻武 任德智 +3 位作者 杨文姬 宋珺 乔锋 李晶 《西南大学学报(自然科学版)》 CAS CSCD 北大核心 2022年第7期59-69,共11页
为探明米拉山土壤结构及团聚体稳定性特征,利用野外调查和室内试验相结合的方法,按照200 m梯度,选取研究区海拔4 200~5 000 m间土壤,对>0.25 mm团聚体的含量、团聚体破坏率(PAD)、平均重量直径(MWD)、几何平均直径(GWD)和分形维数(D... 为探明米拉山土壤结构及团聚体稳定性特征,利用野外调查和室内试验相结合的方法,按照200 m梯度,选取研究区海拔4 200~5 000 m间土壤,对>0.25 mm团聚体的含量、团聚体破坏率(PAD)、平均重量直径(MWD)、几何平均直径(GWD)和分形维数(D)等指标进行分析.结果表明:(1)不同海拔土壤基本理化性质差异有统计学意义.总体上,海拔5 000,4 800 m土壤容质量及孔隙度结构均优于4 200~4 600 m,有机质质量分数随海拔降低先减小后增大,4 600 m有机质质量分数显著(p<0.05)小于其余海拔.(2)研究区土壤机械稳定性及水稳性团聚体均以>0.25 mm粒径为主.总体上机械稳定性团聚体及水稳性团聚体均表现为海拔5 000,4 800 m优于4 200~4 600 m,其MWD,GMD值相对较高,PAD值相对较低,但差异无统计学意义.在干筛与湿筛两种条件下的D值随海拔增加而变小.(3)相关分析表明,土壤有机质、容质量及大团聚体含量直接影响团聚体稳定性.海拔是区域土壤理化性质产生差异、导致土壤团聚体稳定性异同的重要因素.(4)海拔通过改变水热条件,间接影响研究区植被覆盖、有机质周转、土壤侵蚀过程,从而导致土壤结构和团聚体稳定性的差异. 展开更多
关键词 米拉山 垂直地带性 土壤团聚体 团聚体稳定性
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决明子总蒽醌对脂多糖诱导大鼠急性肝损伤的作用及其机制探讨 被引量:12
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作者 蒲加伟 杨雄 +2 位作者 吴余 周霞 王旭 《中国现代医学杂志》 CAS 2020年第20期6-11,共6页
目的观察决明子总蒽醌对脂多糖(LPS)诱导的急性肝损伤(ALI)大鼠的作用及对HMGB1/TLR4/NF-κB信号通路的影响。方法将60只大鼠随机分为对照组、模型组、低剂量组、中剂量组和高剂量组,除对照组外其余大鼠给予尾部静脉注射LPS(5 mg/kg)复... 目的观察决明子总蒽醌对脂多糖(LPS)诱导的急性肝损伤(ALI)大鼠的作用及对HMGB1/TLR4/NF-κB信号通路的影响。方法将60只大鼠随机分为对照组、模型组、低剂量组、中剂量组和高剂量组,除对照组外其余大鼠给予尾部静脉注射LPS(5 mg/kg)复制ALI模型,对照组给予等体积的生理盐水。低、中、高剂量组在模型复制后每日分别给予大鼠灌胃1次10 mg/kg、20 mg/kg及40 mg/kg的决明子总蒽醌,灌胃剂量5 ml,连续给药14 d;对照组和模型组给予同等体积生理盐水。检测大鼠丙氨酸氨基转移酶(ALT)、总胆红素(TBIL)及天门冬氨酸基转移酶(AST),HE染色观察肝组织病理变化,TUNEL染色检测各组大鼠肝组织中的细胞凋亡,ELISA法检测肝组织中的肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)及白细胞介素-1β(IL-1β),Western blotting检测高迁移率族蛋白B1(HMGB1)、Toll样受体4(TLR4)及核因子κB(NF-κB)蛋白表达量。结果模型组ALT、AST及TBIL水平较对照组升高(P<0.05),中、高剂量组较模型组下降(P<0.05)。模型组肝细胞凋亡率较对照组升高(P<0.05),中、高剂量组较模型组下降(P<0.05)。模型组肝组织中IL-6、IL-1β和TNF-α水平较对照组升高(P<0.05),中剂量组、高剂量组较模型组下降(P<0.05)。模型组HMGB1、TLR4及NF-κB蛋白相对表达量较对照组升高(P<0.05),中、高剂量组较模型组下降(P<0.05)。结论决明子总蒽醌可以抑制LPS诱导ALI大鼠的HMGB1/TLR4/NF-κB信号通路的激活,从而减轻炎症反应,发挥对肝脏的保护作用。 展开更多
关键词 药物性肝损伤 急性病 决明子总蒽醌/中草药 脂多糖类
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藏东南泥石流沉积区植被演替过程物种多样性研究 被引量:3
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作者 万丹 梁博 +2 位作者 喻武 聂晓刚 赵薇 《中南林业科技大学学报》 CAS CSCD 北大核心 2018年第1期68-74,共7页
选取藏东南6条不同发生年限的泥石流沟,以时空替代法,分析不同年限泥石流沟沉积区植被演替物种多样性特征,揭示藏东南泥石流沉积区植被演替过程中物种多样性的变化特点。结果表明:演替过程中,物种丰富;先锋种的出现与海拔有一定的关系,2... 选取藏东南6条不同发生年限的泥石流沟,以时空替代法,分析不同年限泥石流沟沉积区植被演替物种多样性特征,揭示藏东南泥石流沉积区植被演替过程中物种多样性的变化特点。结果表明:演替过程中,物种丰富;先锋种的出现与海拔有一定的关系,2 700~3 000 m海拔,乔木先锋种为藏川杨,灌木先锋种为鸡骨柴和高丛珍珠梅,草本植物为苔草;3 300~3 600 m海拔,乔木先锋种为糙皮桦,灌木先锋种为云南锦鸡儿和高丛珍珠梅,草本植物为西南草莓;随着演替的进行,植被群落趋于稳定,物种的丰富度指数和Shannon-wiener多样性指数呈先增高后降低的趋势;演替初期植被群落物种丰富度一般表现为草本层>灌木层>乔木层;灌木层、草本层物种多样性水平随时间有所降低,优势度、均匀度一般表现为乔木层>灌木层>草本层。对于该区泥石流沉积区植被群落的恢复,应遵循各个泥石流沉积区特殊的环境小气候,做到因地制宜,使泥石流沉积区得到迅速的治理。 展开更多
关键词 藏东南 泥石流 群落演替 物种多样性
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藏东南高寒土坡面细沟水流输沙能力变化特征 被引量:4
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作者 喻武 任德智 +3 位作者 张鹏 姚甜甜 万丹 程街亮 《水土保持学报》 CSCD 北大核心 2021年第6期76-82,共7页
为探究高寒土坡面细沟侵蚀过程机理,建立科学的坡面细沟输沙能力因子模型,服务高寒坡面水土流失治理工作,以藏东南高寒土壤为研究对象,采用室内径流放水冲刷试验,探讨不同流量和坡度条件下细沟水流输沙能力特征。结果表明:(1)高寒土坡... 为探究高寒土坡面细沟侵蚀过程机理,建立科学的坡面细沟输沙能力因子模型,服务高寒坡面水土流失治理工作,以藏东南高寒土壤为研究对象,采用室内径流放水冲刷试验,探讨不同流量和坡度条件下细沟水流输沙能力特征。结果表明:(1)高寒土坡面细沟水流输沙能力的临界坡长随输沙能力的增加而变短,范围为3.27~8.31 m;坡度在15°~25°时,临界坡长大约稳定在5.0 m;(2)不同坡度下,高寒土细沟水流输沙能力与流量表现为明显的线性正相关关系(Tc=Aq);小坡度的输沙能力受流量的影响程度大于大坡度;(3)高寒土细沟水流输沙能力与坡度可以用指数方程较好地表示(Tc=-ae(-S/b)+c),输沙能力随坡度的增大先快速增大,后逐渐过渡到平稳,当坡度达到15°时增幅平缓;(4)坡面细沟水流输沙能力可以用二元幂函数方程Tc=1697.83S0.491q1.043表示。通过本模型与其他模型的比较分析,ANSWERS模型在计算高寒土的坡面细沟水流输沙能力还值得商榷,本试验模型、Lei模型与Gao模型均能较好地模拟高寒区细沟侵蚀输沙能力。 展开更多
关键词 高寒土 径流冲刷 输沙能力 模型
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