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Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury
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作者 Mou Gao Qin Dong +3 位作者 Dan Zou Zhijun Yang Lili Guo Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS 2025年第5期1416-1430,共15页
Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells ... Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and repair.We previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological recovery.However,the mechanism of CXCR4 upregulation in induced neural stem cells remains unclear.In this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 expression.However,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial activation.In agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury mice.Notably,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head injury.In conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neural stem cells on microglial activation via upregulation of CXCR4 and Crry,thereby promoting induced neural stem cell–mediated improvement of neuronal injury,cerebral edema,and neurological disorders following closed head injury. 展开更多
关键词 Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell MICROGLIA NEUROINFLAMMATION
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Restless head syndrome:A retrospective study
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作者 Sanjay Prakash Varoon Vadodaria +2 位作者 Niraj Chawda Chetsi S Shah Anurag Prakash 《World Journal of Methodology》 2025年第1期51-59,共9页
BACKGROUND Restless legs syndrome(RLS)is characterized by an urge to move with an unpleasant sensation in the lower limbs.RLS typically affects the legs.However,it can also affect several other body regions,such as th... BACKGROUND Restless legs syndrome(RLS)is characterized by an urge to move with an unpleasant sensation in the lower limbs.RLS typically affects the legs.However,it can also affect several other body regions,such as the arms,abdomen,face,neck,head,and genital area.There are only a few reports of the RLS variant affecting the head.AIM To assess the epidemiological,clinical,and other aspects of the RLS variant affecting the head.METHODS We conducted a retrospective study of 17 adult patients(>18 years)who met the RLS criteria and simultaneously experienced RLS-like symptoms in the head.RESULTS The median age at which symptoms appeared was 41.6 years.Males and females were equally affected(1.1:1).All 17 patients had uncomfortable sensations in the lower legs.Insomnia or disturbed sleep was the most common comorbidity(n=16,88.2%).However,headache was the most common presenting or primary symptom(n=10,70.5%).Dizziness or an abnormal sensation in the head was the second most common presenting symptom(5 patients,29.4%).Other presenting features were leg pain,backache,and generalized body pain.All patients responded favorably to dopaminergic medications.CONCLUSION If RLS-related unpleasant sensations and pain are felt in the head,they may be misinterpreted as headache,dizziness,or psychosomatic symptoms.RLS and headaches in a subset of patients may be two phenotypic manifestations of the same disorder. 展开更多
关键词 Restless legs syndrome Restless head syndrome DOPAMINE headACHE MIGRAINE Tension-type headache
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Surface motion of a semi-elliptical hill for incident plane SH waves 被引量:9
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作者 Jianwen Liang Jia Fu 《Earthquake Science》 CSCD 2011年第5期447-462,共16页
A closed-form analytical solution of surface motion of a semi-elliptical cylindrical hill for incident plane SH waves is presented. Although some previous analytical work had already dealt with hill topography of semi... A closed-form analytical solution of surface motion of a semi-elliptical cylindrical hill for incident plane SH waves is presented. Although some previous analytical work had already dealt with hill topography of semi-circular and shallow circular, our work aims at calculating surface motion of very prolate hill for high incident frequency, and explaining the special vibrating is checked by boundary conditions, numerical results for and some conclusions are obtained. properties of very prolate hill. Accuracy of the solution surface motion of oblate and prolate hills are calculated, 展开更多
关键词 semi-elliptical hill analytical solution plane SH wave surface motion oblate hill prolate hill Mathieu function high frequency
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Simulation model of SAR remote sensing of turbulent wake of semi-elliptical submerged body 被引量:3
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作者 FAN Zhisong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第5期50-60,共11页
In terms of the 2-dimensional hydrodynamic simplified model of a semi-elliptical submerged body moving horizontally at high speed, by using the full-spectrum model of SAR(synthetic aperture radar) remote sensing and... In terms of the 2-dimensional hydrodynamic simplified model of a semi-elliptical submerged body moving horizontally at high speed, by using the full-spectrum model of SAR(synthetic aperture radar) remote sensing and taking the effect of oceanic interior turbulence on surface gravity capillary waves into account, applying the k-ε model of turbulence with internal wave mixing, and adopthag the Nasmyth spectrum of oceanic turbulence, the 2-dimensional simulation model of SAR remote sensing of this semi-elliptical submerged body is built up. Simulation by using this model at X band and C band is made in the northeastern South China Sea (21°00' N, 119°00' E). Satisfactory results of the delay time and delay distance of turbulent surface wake of this semi-elliptical submerged body, as well as the minimum submerged depth at which this submerged body which cannot be discovered by SAR, are obtained through simulation. 展开更多
关键词 semi-elliptical submerged body SAR remote sensing WAKE TURBULENCE lee waves
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Comprehensive investigation of stress intensity factors in rotating disks containing three-dimensional semi-elliptical cracks 被引量:1
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作者 M.FAKOOR S.M.N.GHOREISHI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第11期1565-1578,共14页
Initiation and propagation of cracks in rotating disks may cause catastrophic failures. Therefore, determination of fracture parameters under different working con- ditions is an essential issue. In this paper, a comp... Initiation and propagation of cracks in rotating disks may cause catastrophic failures. Therefore, determination of fracture parameters under different working con- ditions is an essential issue. In this paper, a comprehensive study of stress intensity factors (SIFs) in rotating disks containing three-dimensional (3D) semi-elliptical cracks subjected to different working conditions is carried out. The effects of mechanical prop- erties, rotational velocity, and orientation of cracks on SIFs in rotating disks under cen- trifugal loading are investigated. Also, the effects of using composite patches to reduce SIFs in rotating disks are studied. The effects of patching design variables such as mechanical properties, thickness, and ply angle are investigated separately. The modeling and analytical procedure are verified in comparison with previously reported results in the literature. 展开更多
关键词 stress intensity factor (SIF) semi-elliptical crack rotating disk finite ele-ment analysis (FEA)
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融合MacBERT和Talking⁃Heads Attention实体关系联合抽取模型
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作者 王春亮 姚洁仪 李昭 《现代电子技术》 北大核心 2024年第5期127-131,共5页
针对现有的医学文本关系抽取任务模型在训练过程中存在语义理解能力不足,可能导致关系抽取的效果不尽人意的问题,文中提出一种融合MacBERT和Talking⁃Heads Attention的实体关系联合抽取模型。该模型首先利用MacBERT语言模型来获取动态... 针对现有的医学文本关系抽取任务模型在训练过程中存在语义理解能力不足,可能导致关系抽取的效果不尽人意的问题,文中提出一种融合MacBERT和Talking⁃Heads Attention的实体关系联合抽取模型。该模型首先利用MacBERT语言模型来获取动态字向量表达,MacBERT作为改进的BERT模型,能够减少预训练和微调阶段之间的差异,从而提高模型的泛化能力;然后,将这些动态字向量表达输入到双向门控循环单元(BiGRU)中,以便提取文本的上下文特征。BiGRU是一种改进的循环神经网络(RNN),具有更好的长期依赖捕获能力。在获取文本上下文特征之后,使用Talking⁃Heads Attention来获取全局特征。Talking⁃Heads Attention是一种自注意力机制,可以捕获文本中不同位置之间的关系,从而提高关系抽取的准确性。实验结果表明,与实体关系联合抽取模型GRTE相比,该模型F1值提升1%,precision值提升0.4%,recall值提升1.5%。 展开更多
关键词 MacBERT BiGRU 关系抽取 医学文本 Talking⁃heads Attention 深度学习 全局特征 神经网络
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STOCHASTIC PROPAGATION OF SEMI-ELLIPTICAL SURFACE CRACK
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作者 Zhu Weiqiu Jiang Mingxiao (Department of Mechanics,Zhejiang University,Hangzhou,310027,P.R.China) 《Acta Mechanica Solida Sinica》 SCIE EI 1995年第3期236-244,共9页
The semi-elliptical surface crack growth of structural components with uncertain material resistance under random loading is studied by using the stochastic averaging principle.The FPK equation governing the transitio... The semi-elliptical surface crack growth of structural components with uncertain material resistance under random loading is studied by using the stochastic averaging principle.The FPK equation governing the transition probability density function of crack lengths is derived.The analytical solution of the FPK equation for the case of that the equations for the crack growth in the surface and depth directions are uncoupled is obtained.The effects of the parameters of the stress process and of the material property on the behavior of semi-elliptical fatigue crack growth of the components with deterministic resistance to crack growth in the stationary Gaussian stress process are examined.The comparison of the analytical result with digital simulation shows the effectiveness of the present method. 展开更多
关键词 fatigue crack growth semi-elliptical surface crack fatigue life RELIABILITY stochastic averaging
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Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury 被引量:3
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作者 Mou Gao Qin Dong +4 位作者 Zhijun Yang Dan Zou Yajuan Han Zhanfeng Chen Ruxiang Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期872-880,共9页
Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regen... Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head injury.We previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell replacement.However,the neural regeneration efficiency of induced neural stem cells remains limited.In this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem cells.We found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem cells.Additionally,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived neurons.We predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem cells.Silencing H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 inhibition.Furthermore,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem cells.Notably,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury mice.Our results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury. 展开更多
关键词 closed head injury Ctbp2 induced neural stem cell lncRNA H19 miR-325-3p NEUROGENESIS
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Evaluation of the Formula of Stress Intensity Factor K_1 for Semi-Elliptical Surface Crack
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作者 XU Jing jing, WANG Zhi ling, SHAO Ren xing, WU Yi min School of Mechanical and Electronic Engineering and Automation, Shanghai University, Shanghai 200072, China 《Advances in Manufacturing》 2000年第1期18-21,共4页
The stress intensity factor (SIF) of the semi elliptical surface crack in the finite body under extensional stress is sclculated by using the FEM software ANSYS release 5.5. The correction factor M f of SIF at ... The stress intensity factor (SIF) of the semi elliptical surface crack in the finite body under extensional stress is sclculated by using the FEM software ANSYS release 5.5. The correction factor M f of SIF at different point along the front of the crack is determined.The relation between M f and the semi elliptical shape a/c , the relative crack depth a/b , the variation of angle θ , the relative crack width 2c/w and the relative height width ratio h/w are calculated respectively. Finally the application range and the modification of the engineering formula about SIF is proposed. 展开更多
关键词 FEM semi-elliptical surface crack stress intensity facotor extensional stress finite body
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Knowledge, Attitude, and Practice of Using Helmets in Children amongst Parents to Prevent Head Injuries: A Cross-Sectional Study in Riyadh, Saudi Arabia
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作者 Turki Salah Aldeen Bukhari Abdullah Yahya Aldhban +4 位作者 Anas Abdulrahman Alqasem Dona Jamal Al Hatlani Hareth Aldosaimani Hamad A. Al Madi Khalid Alqahtani 《Open Journal of Pediatrics》 2024年第2期255-265,共11页
Objectives: The primary objective was to characterize the range of Knowledge, Attitude, and Practice (KAP) of Helmet use in children amongst parents to prevent head injuries and death. Methods: This is a cross-section... Objectives: The primary objective was to characterize the range of Knowledge, Attitude, and Practice (KAP) of Helmet use in children amongst parents to prevent head injuries and death. Methods: This is a cross-sectional study, done by online survey using a snowball sampling technique, the number of included responses were 386 parents (Male and female) living in Riyadh Aged 21 - 60 years old or above. Results: The study showed that there is a difference in Parents’ belief in the importance of helmet use while riding a Bicycle vs Motorcycle/Quad bike and that was affected by parents’ education level, almost all the people who answered the survey (76.7%) agree that it is important for their children to wear a helmet when riding both a Bicycle and a Motorcycle or Quadbike with a cumulative percentage of (93.8%). And almost all agreed on multiple approaches to help increase helmet use be it by forcing rental shops to give out helmets, forcing sellers to recommend the use of helmets, increasing awareness campaigns, and imposing fines for not wearing helmets. Conclusions: This study is the first to explore Family helmet use while riding Bicycles and Motorcycles/Quad bikes. Although Parent’s belief in the importance of helmet use for their children was high, it is clear that the level of practice is low. With that the risk of head injuries might be high, our findings suggest that safety interventions for increasing pediatric helmet use are needed to increase helmet use and reduce the risk of head injury and hospitalization. 展开更多
关键词 head Trauma head Injury Helmet Bicycle Motorcycle Quad Bike KAP Knowledge ATTITUDE PRACTICE
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Weight Function Method for Stress Intensity Factor of Internal Surface Semi-elliptical Crack in Elliptical Holes
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作者 XIE Wei HUANG Qi-qing 《International Journal of Plant Engineering and Management》 2007年第2期93-100,共8页
The hatches for inspecting are usually designed with elliptical holes in airplane structures, so computation of the stress intensity factor of three dimensional crack at elliptical holes is pivotal for damage toleranc... The hatches for inspecting are usually designed with elliptical holes in airplane structures, so computation of the stress intensity factor of three dimensional crack at elliptical holes is pivotal for damage tolerance analysis of these structures. In this paper, weight function is derived for a two dimensional through cracks at elliptical holes by applying a compounding method. Stress intensity factor formulas for an internal surface semi-elliptical crack in elliptical holes are obtained wing the three dimensional weight function method. Stress intensity factors for an internal surface semi-elliptical crack in elliptical holes under remote tension are computed. At the same time, research on how radius of curvature for elliptical holes affect stress intensity factors was conducted. Stress intensity factors decrease when radius of curvature increases. Some results and conclusions which are of practical value are given. 展开更多
关键词 compounding method internal surface semi-elliptical crack stress intensity factor weight function elliptical holes
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Experimental and numerical simulation study on forced ventilation and dust removal of coal mine heading surface
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作者 Haotian Zheng Bingyou Jiang +1 位作者 Haoyu Wang Yuannan Zheng 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期204-220,共17页
In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar princ... In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar principles.Through the similar experiment and numerical simulation,the distribution of airflow field in the roadway and the spatial and temporal evolution of dust pollution under the conditions of forced ventilation were determined.The airflow field in the roadway can be divided into three zones:jet zone,vortex zone and reflux zone.The dust concentration gradually decreases from the head to the rear of the roadway.Under the forced ventilation conditions,there is a unilateral accumulation of dust,with higher dust concentrations away from the ducts.The position of the equipment has an interception effect on the dust.The maximum error between the test value and the simulation result is 12.9%,which verifies the accuracy of the experimental results.The research results can provide theoretical guidance for the application of dust removal technology in coal mine. 展开更多
关键词 heading surface Forced ventilation Airflow field Dust pollution
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基于改进Double-Head RCNN的无人机航拍图像小目标检测算法 被引量:1
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作者 王殿伟 胡里晨 +1 位作者 房杰 许志杰 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2024年第7期2141-2149,共9页
为解决无人机航拍图像中小目标特征信息少且容易被噪声干扰导致现有算法漏检率和误检率高的问题,提出一种改进Double-Head Region-卷积神经网络(RCNN)的无人机航拍图像小目标检测算法。在骨干网络ResNet-50上引入Transformer和可变形卷... 为解决无人机航拍图像中小目标特征信息少且容易被噪声干扰导致现有算法漏检率和误检率高的问题,提出一种改进Double-Head Region-卷积神经网络(RCNN)的无人机航拍图像小目标检测算法。在骨干网络ResNet-50上引入Transformer和可变形卷积(DCN)模块,更有效提取小目标特征信息和语义信息;提出一种基于内容感知特征重组(CARAFE)的特征金字塔网络(FPN)结构模块,解决特征融合过程中小目标被背景噪声干扰而丢失特征信息的问题;在区域建议网络中针对小目标尺度分布特点重新设置Anchor生成尺度,进一步提升小目标检测性能。在VisDrone-DET2021数据集上的实验结果表明:所提算法能提取更具有表征能力的小目标特征信息和语义信息,对比Double-Head RCNN算法,所提算法的参数量增加了9.73×10^(6),FPS损失了0.6,但是AP、AP50和AP75分别提升了2.6%、6.2%和2.1%,APs提升了3.1%。 展开更多
关键词 小目标检测 无人机航拍图像 Double-head RCNN TRANSFORMER 内容感知特征重组
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Tilapia Head Glycolipid Alleviates Indomethacin-Induced Gastric Ulcer via Regulating Oxidative Stress and Inflammation Through COX/PGE2 Signaling Pathway in Adult Rats
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作者 WANG Bohui WU Haixing +6 位作者 SHAO Mingyang JIANG Mengqi SU Ruiheng GAO Xia XIA Guanghua SHI Haohao SHEN Xuanri 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期743-754,共12页
The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)rats.The gastric ulce... The aim of this experiment was to investigate the ameliorative effect and molecular mechanism of tilapia head glycolipid(TH-GL)on indomethacin(IDM)-induced gastric ulcer in male Sprague Dawley(SD)rats.The gastric ulcer model was established by oral administration of 30mgkg^(-1) IDM after 7 days of TH-GL or omeprazole(OME)administration in rats.Then the macroscopic gastric injury symptoms,gastric mucosa protective factor cyclooxygenase 1(COX-1),cyclooxygenase 2(COX-2),prostaglandin E_(2)(PGE_(2)),the levels of oxidative stress,and inflammatory cytokine expression levels in the rats were analyzed.The experimental results showed that multiple ulcers appeared on the gastric surface of the rats in the model group.Compared to the model group,TH-GL significantly alleviated gastric ulcers and reduced the gastric damage index in rats.In addition,TH-GL significantly promoted the expression of constitutive enzyme COX-1 while inhibited the expression of inducible enzyme COX-2,and make PGE2 maintain at normal levels.TH-GL also inhibited oxidative stress and inflammatory responses,increased superoxide dismutase(SOD)activity and glutathione(GSH)content,decreased the level of malondialdehyde(MDA)and the content of pro-inflammatory factor.In conclusion,these results suggested that TH-GL could maintain the expression levels of COX-1 and PGE2 while inhibit the expression of COX-2 in the gastric of rat and then prevent IDM-induced gastric ulcer,which may be related to the regulation of oxidative stress and inflammatory response.Therefore,TH-GL might be a new option for the prevention of gastric diseases induced by IDM. 展开更多
关键词 tilapia head glycolipid indomethacin gastric ulcer oxidative stress INFLAMMATION
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Basal defense is enhanced in a wheat cultivar resistant to Fusarium head blight
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作者 Xinlong Gao Fan Li +7 位作者 Yikun Sun Jiaqi Jiang Xiaolin Tian Qingwen Li Kaili Duan Jie Lin Huiquan Liu Qinhu Wang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1238-1258,共21页
Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threa... Fusarium head blight(FHB),mainly caused by the fungal pathogen Fusarium graminearum,is one of the most destructive wheat diseases.Besides directly affecting the yield,the mycotoxin residing in the kernel greatly threatens the health of humans and livestock.Xinong 979(XN979)is a widely cultivated wheat elite with high yield and FHB resistance.However,its resistance mechanism remains unclear.In this study,we studied the expression of genes involved in plant defense in XN979 by comparative transcriptomics.We found that the FHB resistance in XN979 consists of two lines of defense.The first line of defense,which is constitutive,is knitted via the enhanced basal expression of lignin and jasmonic acid(JA)biosynthesis genes.The second line of defense,which is induced upon F.graminearum infection,is contributed by the limited suppression of photosynthesis and the struggle of biotic stress-responding genes.Meanwhile,the effective defense in XN979 leads to an inhibition of fungal gene expression,especially in the early infection stage.The formation of the FHB resistance in XN979 may coincide with the breeding strategies,such as selecting high grain yield and lodging resistance traits.This study will facilitate our understanding of wheat-F.graminearum interaction and is insightful for breeding FHB-resistant wheat. 展开更多
关键词 Fusarium head blight Xinong 979 LIGNIN jasmonic acid PHOTOSYNTHESIS Fusarium graminearum
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YOLO-MFD:Remote Sensing Image Object Detection with Multi-Scale Fusion Dynamic Head
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作者 Zhongyuan Zhang Wenqiu Zhu 《Computers, Materials & Continua》 SCIE EI 2024年第5期2547-2563,共17页
Remote sensing imagery,due to its high altitude,presents inherent challenges characterized by multiple scales,limited target areas,and intricate backgrounds.These inherent traits often lead to increased miss and false... Remote sensing imagery,due to its high altitude,presents inherent challenges characterized by multiple scales,limited target areas,and intricate backgrounds.These inherent traits often lead to increased miss and false detection rates when applying object recognition algorithms tailored for remote sensing imagery.Additionally,these complexities contribute to inaccuracies in target localization and hinder precise target categorization.This paper addresses these challenges by proposing a solution:The YOLO-MFD model(YOLO-MFD:Remote Sensing Image Object Detection withMulti-scale Fusion Dynamic Head).Before presenting our method,we delve into the prevalent issues faced in remote sensing imagery analysis.Specifically,we emphasize the struggles of existing object recognition algorithms in comprehensively capturing critical image features amidst varying scales and complex backgrounds.To resolve these issues,we introduce a novel approach.First,we propose the implementation of a lightweight multi-scale module called CEF.This module significantly improves the model’s ability to comprehensively capture important image features by merging multi-scale feature information.It effectively addresses the issues of missed detection and mistaken alarms that are common in remote sensing imagery.Second,an additional layer of small target detection heads is added,and a residual link is established with the higher-level feature extraction module in the backbone section.This allows the model to incorporate shallower information,significantly improving the accuracy of target localization in remotely sensed images.Finally,a dynamic head attentionmechanism is introduced.This allows themodel to exhibit greater flexibility and accuracy in recognizing shapes and targets of different sizes.Consequently,the precision of object detection is significantly improved.The trial results show that the YOLO-MFD model shows improvements of 6.3%,3.5%,and 2.5%over the original YOLOv8 model in Precision,map@0.5 and map@0.5:0.95,separately.These results illustrate the clear advantages of the method. 展开更多
关键词 Object detection YOLOv8 MULTI-SCALE attention mechanism dynamic detection head
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Bilateral Avascular Necrosis of the Femoral Head in Renal Transplant Recipient: A Case Report
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作者 Imane Saidi Moulay Omar Lamrani +1 位作者 Naima Ouzeddoun Tarik Bouattar 《Open Journal of Nephrology》 2024年第2期253-261,共9页
Osteoarticular complications are common after renal transplantation. The complications may result from the bone condition prior to transplantation or the iatrogenic effects of the treatments administered. These compli... Osteoarticular complications are common after renal transplantation. The complications may result from the bone condition prior to transplantation or the iatrogenic effects of the treatments administered. These complications lead to significant morbidity and mortality, in addition to chronic pain and functional impairment. We report the clinical case of bilateral avascular necrosis (AVN) of the femoral head in a kidney transplant recipient. Clinical Case: 53-year-old male with a history of chronic hypertension. He underwent chronic hemodialysis for 12 months and was treated with Entecavir for chronic hepatitis B. The patient received a kidney transplant from a non-related living donor. Induction therapy included Thymoglobulin along with tapered corticosteroids, reaching a dose of 5 mg/day after 3 months, Mycophenolate mofetil (2 g/day), and Tacrolimus adjusted based on residual levels. There was good recovery of renal graft function. After six months, the patient reported bilateral hip pain and functional impairment of both lower limbs. Pelvic X-rays showed signs suggestive of bilateral AVN of the femoral heads. The diagnosis was confirmed by MRI. The patient underwent right hip drilling and total left hip replacement (THR). A right THR was performed a year later. Conclusion: AVN constitutes a frequent cause of morbidity and mortality after RT. The pathophysiology of osteonecrosis remains complex and multifactorial. We emphasize the importance of conducting a thorough assessment of bone health in patients both before and after RT. 展开更多
关键词 Avascular Necrosis Femoral head Osteoarticular Complications Renal Transplant
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A Dual-Cluster-Head Based Medium Access Control for Large-Scale UAV Ad-Hoc Networks
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作者 Zhao Xinru Wei Zhiqing +3 位作者 Zou Yingying Ma Hao Cui Yanpeng Feng Zhiyong 《China Communications》 SCIE CSCD 2024年第5期123-136,共14页
Unmanned Aerial Vehicle(UAV)ad hoc network has achieved significant growth for its flexibility,extensibility,and high deployability in recent years.The application of clustering scheme for UAV ad hoc network is impera... Unmanned Aerial Vehicle(UAV)ad hoc network has achieved significant growth for its flexibility,extensibility,and high deployability in recent years.The application of clustering scheme for UAV ad hoc network is imperative to enhance the performance of throughput and energy efficiency.In conventional clustering scheme,a single cluster head(CH)is always assigned in each cluster.However,this method has some weaknesses such as overload and premature death of CH when the number of UAVs increased.In order to solve this problem,we propose a dual-cluster-head based medium access control(DCHMAC)scheme for large-scale UAV networks.In DCHMAC,two CHs are elected to manage resource allocation and data forwarding cooperatively.Specifically,two CHs work on different channels.One of CH is used for intra-cluster communication and the other one is for inter-cluster communication.A Markov chain model is developed to analyse the throughput of the network.Simulation result shows that compared with FM-MAC(flying ad hoc networks multi-channel MAC,FM-MAC),DCHMAC improves the throughput by approximately 20%~50%and prolongs the network lifetime by approximately 40%. 展开更多
关键词 dual cluster head medium access control UAV swarm
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Surgical Treatment of Osteonecrosis of the Femoral Head Using Minimally Invasive Surgical Drilling and Cancellous Grafting at Brazzaville University Hospital
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作者 Kevin Parfait Bienvenu Bouhelo-Pam Marius Monka +4 位作者 Arnauld Sledje Wilfrid Bilongo Bouyou Regis Perry Massouama Paul Yèlai Ikounga Roger Bertrand Sah Mbou Armand Moyikoua 《Open Journal of Orthopedics》 2024年第2期122-132,共11页
Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling... Introduction: Osteonecrosis of the femoral head (ONTF) is a debilitating condition. Several treatments have been proposed with controversial results. The aim of our study was to evaluate treatment by surgical drilling coupled with in situ cancellous grafting. Materials and methods: Our study was a case-control study conducted at Brazzaville University Hospital from 1st January 2018 to 31 December 2023. It compared two groups of patients with ONTF: non-operated (13 patients, 20 hips) and operated (22 patients, 35 hips). We used the visual digital scale (VDS) for pain assessment, the Merle D’Aubigne-Postel (MDP) scoring system for clinical and functional assessment, and the evolution of necrosis. Results: The group of non-operated patients had a mean age of 35.69 ± 3.4 years, no improvement in pain with an EVN above seven at the last recoil and a mean global MDP score falling from 12.7 before offloading to 10.13 at one year. The group of patients operated on had a mean age of 37.86 ± 7.02 years, a significant reduction in pain (p = 0.00004) and a significantly increased MDP score (p = 0.0034). A comparison of the two groups of patients showed significant stabilization of the necrotic lesions in the operated patients (p = 0.00067), with better satisfaction in the same group. Conclusion: Surgical drilling combined with grafting in the treatment of early-stage ONTF has improved progress in our series. The technique is reproducible and less invasive. It has made it possible to delay unfavorable progression and, consequently, hip replacement surgery. 展开更多
关键词 HIP Osteonecrosis of the Femoral head Conservative Treatment Surgical Drilling Bone Grafting
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Fetal Head Compression: Its Possible Role in Neurologic Injury
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作者 Barry S. Schifrin Brian J. Koos Wayne R. Cohen 《Open Journal of Obstetrics and Gynecology》 2024年第1期124-143,共20页
It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several c... It is widely assumed that fetal ischemic brain injury during labor derives almost exclusively from severe, systemic hypoxemia with marked neonatal depression and acidemia. Severe asphyxia, however, is one of several causes of perinatal neurological injury and may not be the most common;most neonates diagnosed with hypoxic-ischemic encephalopathy do not have evidence of severe asphyxia. Sepsis, direct brain trauma, and drug or toxin exposure account for some cases, while mechanical forces of labor and delivery that increase fetal intracranial pressure sufficiently to impair brain perfusion may also contribute. Because of bony compliance and mobile suture lines, the fetal skull changes shape and redistributes cerebrospinal fluid during labor according to constraints imposed by contractions, and bony and soft tissue elements of the birth canal as the head descends. These accommodations, including the increase in intracranial pressure, are adaptive and necessary for efficient descent of the head while safeguarding cerebral blood flow. Autonomic reflexes mediated through central receptors normally provide ample protection of the brain from the considerable pressure exerted on the skull. On occasion, those forces, which are transmitted intracranially, may overcome the various adaptive anatomical, cardiovascular, metabolic, and neurological mechanisms that maintain cerebral perfusion and oxygen availability, resulting in ischemic brain injury. Accepting the notion of a potentially adverse impact of fetal head compression suggests that avoidance of excessive uterine activity and of relentless pushing without steady progress in descent may offer protection for the fetal brain during parturition. Excessive head compression should be considered in the differential diagnosis of ischemic encephalopathy. 展开更多
关键词 Fetal Brain Injury Fetal head Compression Ischemic Encephalopathy Neonatal Encephalopathy
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