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Cross-sectional analysis of hearing loss,age and tinnitus severity in a web-recruited cohort of 610 subjects
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作者 María Cuesta Pedro Cobo 《Journal of Otology》 2026年第1期38-49,共12页
Tinnitus:the hearing of a sound that has not been produced by any external or internal source,is a rather heterogeneous hearing disorder.Background/Objectives:Hearing loss has been shown to be the main risk factor for... Tinnitus:the hearing of a sound that has not been produced by any external or internal source,is a rather heterogeneous hearing disorder.Background/Objectives:Hearing loss has been shown to be the main risk factor for tinnitus while emotional disorders are risk factors for developing intrusive or bothersome tinnitus.Moreover,aging has also been identified as another risk factor.The aim of this paper was to analyse the correlation between hearing loss,age and tinnitus severity in a cohort of 610 tinnitus sufferers.Methods:Age,audiometric(hearing condition)and tinnitus(time duration and severity)data were assessed and analysed for all subjects just after recruiting(baseline).Furthermore,the average hearing loss(HL)curves of the participants for age groups were compared to these with the corresponding Age Related HL(ARHL).Results:For most of the age groups,the measured HL curves exceeded in 10-20 dB those of the ARHL.The average age of tinnitus onset(age minus tinnitus duration)was found to be 44-46 years in both men and women.Weak correlation between audiometric feature and tinnitus distress was observed.Conclusions:Hearing loss has been shown to be a clear risk factor for triggering tinnitus(86%of participants were hearing impaired).In this cohort,average measures of hearing loss showed,at most,weak associations with tinnitus-related distress,suggesting that non-audiological factors may play a predominant role. 展开更多
关键词 TINNITUS Age Hearing loss Tinnitus-related distress
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Neurobrucellosis:An Uncommon but Important Cause of Sensorineural Hearing Loss:a case report
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作者 Karim Messaoudi Walid Yacine Mohamed Cherif 《Journal of Otology》 2026年第1期22-26,共5页
Background:Brucellosis is a zoonotic infection common in Mediterranean countries and the Middle East.Neurological involvement,although rare,can lead to severe complications,including sensorineural hearing loss(SNHL).T... Background:Brucellosis is a zoonotic infection common in Mediterranean countries and the Middle East.Neurological involvement,although rare,can lead to severe complications,including sensorineural hearing loss(SNHL).This case is particularly noteworthy as it highlights irreversible auditory nerve damage in brucellosis,emphasizing the importance of early diagnosis and treatment to prevent permanent neurological consequences.The novelty of this case lies in the severity of auditory involvement despite timely treatment.Case Presentation:A 43-year-old male farmer of Maghrebi origin presented with neurobrucellosis complicated by severe,irreversible bilateral sensorineural hearing loss.The patient initially reported symptoms of hearing loss and dizziness,which were confirmed to be associated with auditory nerve involvement.Wright's serology and polymerase chain reaction(PCR)testing confirmed brucellosis.Despite appropriate and prolonged antibiotic therapy,including drugs that penetrate the meningeal barrier and act intracellularly,the patient's auditory impairment remained permanent.The patient is currently a candidate for cochlear implantation to manage his severe hearing loss.Neurological symptoms did not improve with treatment,but cochlear implantation may offer a potential solution to his hearing deficit.Conclusions:This case highlights the importance of early recognition and intervention in brucellosis cases,particularly those with neurological involvement.Delayed diagnosis and treatment can result in irreversible neurological damage.It also underscores the potential for cochlear implantation in patients with severe,irreversible sensorineural hearing loss caused by neurobrucellosis.Cochlear implantation offers an important solution for patients with brucellosis-related hearing deficits,improving their quality of life despite the neurological damage caused by the infection. 展开更多
关键词 BRUCELLOSIS ZOONOSIS Sensorineural hearing loss DIZZINESS
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Overexpression of OsCAX2 in indica rice reduces cadmium accumulation in grains without yield loss
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作者 Zhi Hu Wenli Zou +4 位作者 Huijing Ye Jie Ma Lijun Meng Jingguang Chen Guoyou Ye 《Journal of Integrative Agriculture》 2026年第1期390-393,共4页
Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to h... Highlights OsCAX2 is localized to tonoplast,and cadmium induces its expression.OsCAX2 overexpression reduces cadmium concentration in indica rice grains by 49.1%.Cadmium(Cd)exposure poses significant health risks to humans,and the International Agency for Research on Cancer has classified it as a Group I carcinogen.Cadmium undergoes minimal metabolism in the human body;consequently,prolonged Cd^(2+)exposure can cause severe damage to multiple organs including the liver,kidneys,lungs,bones,and immune system(Shao et al.2024).Rice,one of the three global staple crops,and Cd exposure in humans primarily occurs the consumption of contaminated rice grains.The contribution of rice to the total dietary Cd intake is over 50% for non-smoking Asian populations(Chen et al.2018;Shi et al.2020). 展开更多
关键词 GRAIN cadmium accumulation yield loss cadmium concentration indica rice grains OscAX TONOPLAST cadmium induction
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A relay-based probabilistic prediction model for multi-fidelity scenarios in total pressure loss of a compressor cascade with micro-textured surfaces
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作者 Liyue WANG Cong WANG +2 位作者 Xinyue LAN Haochen ZHANG Gang SUN 《Chinese Journal of Aeronautics》 2026年第1期55-65,共11页
The micro-riblet structures have been demonstrated effective in controlling the Total Pressure Loss(TPL)of aero-engine blades.However,due to the considerable scale gap between micro-texture and an actual aero-engine b... The micro-riblet structures have been demonstrated effective in controlling the Total Pressure Loss(TPL)of aero-engine blades.However,due to the considerable scale gap between micro-texture and an actual aero-engine blade,wind tunnel tests and numerical simulations with massive grids directly describing the global flow field are costly for aerodynamic evaluation.Furthermore,the fine micro surface structure brings unavoidable manufacturing errors,and the probability prediction contributes to gaining the confidence interval of the results.Therefore,a novel relay-based probabilistic model for multi-fidelity scenarios in the TPL prediction of a compressor cascade with micro-riblet surfaces is proposed to trade off accuracy and efficiency.Combined with the low-fidelity flow data generated by an aerodynamic solution strategy using the boundary surrogate model and the high-fidelity flow data from the experiment,the relay-based modeling has been achieved through knowledge transferring,and the confidence interval can be provided by the Gaussian Process Regression(GPR)model.The TPL of compressor cascades with micro-riblet surfaces under different surface structures at March number Ma=0.64,0.74,0.84 have been evaluated using the Relay-Based Probabilistic(RBP)model.The results illustrate that the RBP model could provide higher accuracy than the Single-Fidelity-Data-Driven(SFDD)prediction model,which show the promising potential of multi-fidelity scenarios data fusion in the aerodynamic evaluation of multi-scale configurations. 展开更多
关键词 Knowledge transfer Micro-riblet Multi-fidelity surrogate Probability prediction model Total pressure loss
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Association of conventional chromosomal polymorphic variants in 580 couples with idiopathic recurrent pregnancy loss:A retrospective cohort study
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作者 Sunny Kumar Jignesh Kumar Patel Amit Roy Chowdhury +2 位作者 Shagufa Sheikh Purna Chandra Mahapatra Birendranath Banerjee 《Asian pacific Journal of Reproduction》 2026年第1期11-22,共12页
Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Ph... Objective:To investigate the potential link between chromosomal polymorphisms in couples who had a medical history of idiopathic recurrent pregnancy loss.Methods:Cytogenetic investigation was conducted with mitogen(Phytohemagglutinin-M,Gibco)stimulated blood T lymphocytes by Giemsa trypsin Giemsa banding and Ag-NOR banding on 580 couples with a history of idiopathic recurrent pregnancy loss and 240 couples from the general population.Thirty good chromosomal spreads were captured,karyotyped,and analyzed.The karyotypes were designated using the International System for Human Cytogenomic Nomenclature 2024.Pearson Chi-square test was used to compare the frequency of chromosomal polymorphism variations in the idiopathic recurrent pregnancy loss group with the general population group.Results:A conventional cytogenetic investigation revealed that 45.43%of couples experiencing idiopathic recurrent pregnancy loss presented with various types of chromosomal polymorphic variants,compared to 11.88%in the general population.The overall frequency of these chromosomal polymorphic variants was significantly higher in the idiopathic recurrent pregnancy loss group compared to the general population group(OR 9.97,95%CI 6.99-14.21;P<0.05).Additionally,the prevalence of polymorphic variants was higher among males(49.14%)than females(41.72%)(P=0.01).Conclusions:Chromosomal polymorphic analysis may play a crucial role in the assessment and careful clinical management of cases with idiopathic recurrent pregnancy loss,especially when no other conclusive reasons are identified during the initial evaluation.Therefore,heteromorphism should not be overlooked while investigating the causes of idiopathic recurrent pregnancy loss. 展开更多
关键词 Polymorphic variants Chromosomal anomalies Repeated pregnancy loss Cytogenetic investigation
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Influence of long-term livestock manure substitution on water erosion and labile organic carbon lateral loss on subtropical sloping croplands
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作者 Keke Hua Bo Zhu +5 位作者 Zhibin Guo Daozhong Wang Linchuan Zhan Lin Jin Hirohiko Nagano Kazuyuki Inubushi 《Journal of Integrative Agriculture》 2026年第2期481-492,共12页
The lateral transport of labile organic carbon represents a critical pathway for soil organic carbon(SOC) loss,reducing organic carbon sequestration and increasing the risk of waterbody pollution.Livestock manure appl... The lateral transport of labile organic carbon represents a critical pathway for soil organic carbon(SOC) loss,reducing organic carbon sequestration and increasing the risk of waterbody pollution.Livestock manure application on croplands serves as a common fertilizer reduction practice to sustain crop yields,enhance SOC sequestration,and reduce water erosion.However,limited quantitative assessments have examined the effects of livestock manure substitution on labile organic carbon lateral loss and fluxes in long-term experiments.This study conducted a three-year field investigation on subtropical sloping croplands to assess the impact of livestock manure substitution on dissolved organic carbon(DOC) and particulate organic carbon(POC) loss via surface runoff,interflow and eroded sediments.There are four treatments:no fertilization(CK);chemical nitrogen fertilizer(SF),40% nitrogen substitution with pig manure(PMF),and 100% nitrogen substitution from pig manure(PM).Compared to SF treatment,long-term livestock manure substitution in PMF and PM treatments significantly(P<0.05) reduced annual cumulative surface runoff fluxes by 13.5 and 21.6%,respectively.Manure applications decreased annual sediment fluxes by 12.9 and 19.1%,respectively.Soil water stable aggregates for mean weight diameter(MWD) increased significantly by 37.7 and 73.6%.Annual cumulative POC loss flux via eroded sediment under PMF and PM treatments increased significantly(P<0.05) by 61.1 and 47.9%,respectively.The labile organic carbon loss fluxes,including DOC and POC losses,under PMF and PM treatments increased significantly(P<0.05) by 11.9 and 31.4%,respectively.These results demonstrate that while water erosion intensity decreases due to enhanced soil aggregate stability,the risk of labile organic carbon loss increases after long-term livestock manure substitution in subtropical sloping croplands.Future research should examine labile organic carbon lateral migration under various soil types and slope gradients for livestock manure application in subtropical agricultural ecosystem croplands to better understand extreme rainfall effects. 展开更多
关键词 hydrological carbon loss runoff and sediment organic manure sloping croplands
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Extreme Attitude Prediction of Amphibious Vehicles Based on Improved Transformer Model and Extreme Loss Function
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作者 Qinghuai Zhang Boru Jia +3 位作者 Zhengdao Zhu Jianhua Xiang Yue Liu Mengwei Li 《哈尔滨工程大学学报(英文版)》 2026年第1期228-238,共11页
Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instabili... Amphibious vehicles are more prone to attitude instability compared to ships,making it crucial to develop effective methods for monitoring instability risks.However,large inclination events,which can lead to instability,occur frequently in both experimental and operational data.This infrequency causes events to be overlooked by existing prediction models,which lack the precision to accurately predict inclination attitudes in amphibious vehicles.To address this gap in predicting attitudes near extreme inclination points,this study introduces a novel loss function,termed generalized extreme value loss.Subsequently,a deep learning model for improved waterborne attitude prediction,termed iInformer,was developed using a Transformer-based approach.During the embedding phase,a text prototype is created based on the vehicle’s operation log data is constructed to help the model better understand the vehicle’s operating environment.Data segmentation techniques are used to highlight local data variation features.Furthermore,to mitigate issues related to poor convergence and slow training speeds caused by the extreme value loss function,a teacher forcing mechanism is integrated into the model,enhancing its convergence capabilities.Experimental results validate the effectiveness of the proposed method,demonstrating its ability to handle data imbalance challenges.Specifically,the model achieves over a 60%improvement in root mean square error under extreme value conditions,with significant improvements observed across additional metrics. 展开更多
关键词 Amphibious vehicle Attitude prediction Extreme value loss function Enhanced transformer architecture External information embedding
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Weight loss induced bone loss:mechanism of action and clinical implications
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作者 Hanghang Liu Bolun Li +2 位作者 Linyi Liu Wangyang Ying Clifford J.Rosen 《Bone Research》 2025年第6期1327-1341,共15页
Weight loss,whether resulting from disease-related conditions or intentional interventions,has been increasingly recognized as a significant risk factor for compromised skeletal integrity.While moderate weight reducti... Weight loss,whether resulting from disease-related conditions or intentional interventions,has been increasingly recognized as a significant risk factor for compromised skeletal integrity.While moderate weight reduction may yield metabolic benefits,rapid or sustained weight loss is frequently associated with decreased bone mineral density,deterioration of bone microarchitecture,and heightened fracture risk.The mechanisms underlying weight loss–induced bone loss are complex and multifactorial.Emerging evidence highlights a range of contributing factors,including reduced mechanical loading,increased bone marrow adiposity,hormonal and endocrine alterations,nutritional deficiencies,and disruptions in energy metabolism.These mechanisms are intricately interconnected,ultimately impairing bone remodeling and homeostatic balance.In this review,we provide a comprehensive analysis of the current literature on the mechanistic pathways,clinical consequences,and therapeutic strategies related to weight loss–induced bone loss.We further differentiate the skeletal effects of disease-associated versus interventioninduced weight loss,with a focus on their distinct molecular underpinnings.Our goal is to offer novel insights into the optimization of bone health management in the context of weight loss,guided by a translational medicine perspective. 展开更多
关键词 bone loss weight loss induced decreased bone mineral densitydeterioration bone microarchitectureand weight reduction weight losswhether mechanism action weight loss compromised skeletal integritywhile
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基于PolyLoss函数的不平衡犯罪隐语文本增强方法
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作者 李文邦 颜靖华 董泽 《数据与计算发展前沿(中英文)》 2026年第1期158-167,共10页
【目的】为解决犯罪隐语数据集存在的不平衡问题,进一步提升对犯罪隐语文本的分类效果。【方法】对于长文本,提出SimPoly方法;对于短文本,提出EDAPoly方法。【结果】实验结果表明,SimPoly和EDAPoly方法在解决犯罪隐语数据集不平衡问题... 【目的】为解决犯罪隐语数据集存在的不平衡问题,进一步提升对犯罪隐语文本的分类效果。【方法】对于长文本,提出SimPoly方法;对于短文本,提出EDAPoly方法。【结果】实验结果表明,SimPoly和EDAPoly方法在解决犯罪隐语数据集不平衡问题上显著提升了分类模型的表现,相较于未进行文本增强的基线方法,在准确率、召回率和F1分数等指标上均有明显提升。【结论】不仅为罪隐语识别技术的实际应用提供了一种有效的解决方案,也为类似的不平衡文本分类任务提供了新的思路和支持。 展开更多
关键词 犯罪隐语 文本增强 损失函数 不平衡文本处理
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Bifidobacterium animalis subsp.lactis A6 ameliorates bone and muscle loss via modulating gut microbiota composition and enhancing butyrate production
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作者 Ming Chen Yi Li +18 位作者 Zhengyuan Zhai Hui Wang Yuan Lin Feifan Chang Siliang Ge Xinyu Sun Wei Wei Duanyang Wang Mingming Zhang Ruijing Chen Haikuan Yu Taojin Feng Xiang Huang Dongliang Cheng Jiang Liu Wenxuan Di Yanling Hao Pengbin Yin Peifu Tang 《Bone Research》 2025年第3期570-588,共19页
Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through mic... Systematic bone and muscle loss is a complex metabolic disease,which is frequently linked to gut dysfunction,yet its etiology and treatment remain elusive.While probiotics show promise in managing diseases through microbiome modulation,their therapeutic impact on gut dysfunction-induced bone and muscle loss remains to be elucidated.Employing dextran sulfate sodium(DSS)-induced gut dysfunction model and wide-spectrum antibiotics(ABX)-treated mice model,our study revealed that gut dysfunction instigates muscle and bone loss,accompanied by microbial imbalances.Importantly,Bifidobacterium animalis subsp.lactis A6(B.lactis A6)administration significantly ameliorated muscle and bone loss by modulating gut microbiota composition and enhancing butyrate-producing bacteria.This intervention effectively restored depleted butyrate levels in serum,muscle,and bone tissues caused by gut dysfunction.Furthermore,butyrate supplementation mitigated musculoskeletal loss by repairing the damaged intestinal barrier and enriching beneficial butyrate-producing bacteria.Importantly,butyrate inhibited the NF-κB pathway activation,and reduced the secretion of corresponding inflammatory factors in T cells.Our study highlights the critical role of dysbiosis in gut dysfunction-induced musculoskeletal loss and underscores the therapeutic potential of B.lactis A6.These discoveries offer new microbiome directions for translational and clinical research,providing promising strategies for preventing and managing musculoskeletal diseases. 展开更多
关键词 bone loss muscle loss bone muscle loss gut dysfunctionyet instigates muscle microbiome modulationtheir gut dysfunction managing diseases
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Evaluation of plasma antioxidant activity in women with early pregnancy losses
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作者 Olga Gennadievna Tishkova Lydmila Vasilievna Dikareva +2 位作者 Nadezhda Titovna Berberova Maria Alexandrovna Polovinkina Victoria Pavlovna Osipova 《Journal of Biomedical Research》 2025年第6期651-654,共4页
Dear Editor,Early pregnancy loss is a condition whose relevance is determined not only by high incidence but also by the frequency of this pathology progressing into habitual miscarriage.According to the American Preg... Dear Editor,Early pregnancy loss is a condition whose relevance is determined not only by high incidence but also by the frequency of this pathology progressing into habitual miscarriage.According to the American Pregnancy Association,non-developing pregnancy(NDP),one of the forms of pregnancy loss,accounts for half of all miscarriages in the early stages[1]. 展开更多
关键词 habitual miscarriage pregnancy loss non developing pregnancy early pregnancy loss plasma antioxidant activity pregnancy lossaccounts
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Inhibition of the NLRP3 inflammasome attenuates spiral ganglion neuron degeneration in aminoglycoside-induced hearing loss 被引量:1
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作者 Jia Fang Zhuangzhuang Li +8 位作者 Pengjun Wang Xiaoxu Zhang Song Mao Yini Li Dongzhen Yu Xiaoyan Li Yazhi Xing Haibo Shi Shankai Yin 《Neural Regeneration Research》 SCIE CAS 2025年第10期3025-3039,共15页
Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial spectrum.However,their use leads to irreversible hearing damage by causing apoptosis of hair cells as ... Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial spectrum.However,their use leads to irreversible hearing damage by causing apoptosis of hair cells as their direct target.In addition,the hearing damage caused by aminoglycosides involves damage of spiral ganglion neurons upon exposure.To investigate the mechanisms underlying spiral ganglion neuron degeneration induced by aminoglycosides,we used a C57BL/6J mouse model treated with kanamycin.We found that the mice exhibited auditory deficits following the acute loss of outer hair cells.Spiral ganglion neurons displayed hallmarks of pyroptosis and exhibited progressive degeneration over time.Transcriptomic profiling of these neurons showed significant upregulation of genes associated with inflammation and immune response,particularly those related to the NLRP3 inflammasome.Activation of the canonical pyroptotic pathway in spiral ganglion neurons was observed,accompanied by infiltration of macrophages and the release of proinflammatory cytokines.Pharmacological intervention targeting NLRP3 using Mcc950 and genetic intervention using NLRP3 knockout ameliorated spiral ganglion neuron degeneration in the injury model.These findings suggest that NLRP3 inflammasome-mediated pyroptosis plays a role in aminoglycoside-induced spiral ganglion neuron degeneration.Inhibition of this pathway may offer a potential therapeutic strategy for treating sensorineural hearing loss by reducing spiral ganglion neuron degeneration. 展开更多
关键词 DEGENERATION hearing loss macrophages Mcc950 neuroinflammation NLRP3 inflammasome OTOTOXICITY pyroptosis sensorineural hearing loss spiral ganglion neuron
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Evaluating foot reflexology as a proposed treatment for sensorineural hearing loss:A critical review
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作者 Carina McClean Brandon Lucke-Wold 《World Journal of Clinical Cases》 SCIE 2025年第4期15-17,共3页
This editorial critically evaluates the application of foot reflexology as a treatment for sensorineural hearing loss(SNHL)in infants,as proposed in a case report published in the World of Clinical Cases.SNHL is a con... This editorial critically evaluates the application of foot reflexology as a treatment for sensorineural hearing loss(SNHL)in infants,as proposed in a case report published in the World of Clinical Cases.SNHL is a condition characterized by damage to the cochlea or the neural pathways that transmit auditory information to the brain.The etiology of SNHL is often complex,involving genetic mutations,prenatal factors,or perinatal insults.Reflexology,an alternative therapy involving the application of pressure to specific points on the feet,is based on the hypothesis that these points correspond to different organs and systems in the body,including the auditory system.However,the biological plausibility and clinical efficacy of foot reflexology in addressing SNHL lack empirical support.This editorial examines the pathophysiology of SNHL,assesses the clinical claims of reflexology practitioners,and emphasizes the necessity of evidence-based approaches in treating infant hearing loss.While complementary therapies may provide ancillary benefits,they should not supplant validated medical treatments in managing SNHL in infants.Further research is needed to evaluate the safety and efficacy of foot reflexology and other alternative therapies in pediatric audiology. 展开更多
关键词 Sensorineural hearing loss REFLEXOLOGY Congenital hearing loss Alternative medicine AUDIOLOGY
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Compact Ultra-Low Loss Optical True Delay Line on Thin Film Lithium Niobate
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作者 Yuan Ren Bo-Yang Nan +6 位作者 Rong-Bo Wu Yong Zheng Rui-Xue Liu Xue-Wen Wang Yun-Peng Song Min Wang Ya Cheng 《Chinese Physics Letters》 2025年第7期145-149,共5页
We report the fabrication of an 8-meter-long thin-flm lithium niobate optical true delay line using the photolithography-assisted chemomechanical etching technique,showing a low transmission loss of 0.036 dB/cm in the... We report the fabrication of an 8-meter-long thin-flm lithium niobate optical true delay line using the photolithography-assisted chemomechanical etching technique,showing a low transmission loss of 0.036 dB/cm in the conventional telecom band. 展开更多
关键词 conventional telecom band COMPACT transmission loss optical true delay line true delay line thin film ultra low loss lithium niobate
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Construction of multiple heterogeneous interfaces induced by rGO-multimetallic LDH derivatives to improve dielectric loss for enhanced electromagnetic wave absorption
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作者 Yuan Guo Yuping Duan +4 位作者 Xiaoji Liu Yupeng Shi Zeng Fan Huifang Pang Lujun Pan 《Journal of Materials Science & Technology》 2025年第34期288-297,共10页
The rational construction of lightweight composites with multiple heterogeneous interfaces represents an effective strategy for achieving efficient electromagnetic wave(EMW)absorption.However,the impact of multiple he... The rational construction of lightweight composites with multiple heterogeneous interfaces represents an effective strategy for achieving efficient electromagnetic wave(EMW)absorption.However,the impact of multiple heterogeneous interfaces on electromagnetic performance still needs further exploration.Herein,reduced graphene oxide(rGO)@Ni-FeCo layered hydroxide(LDH)derivatives with multiple heterostructures were synthesized by a series of processes including electrostatic self-assembly,freeze-drying and thermal annealing.The conductive network in rGO and the cavities inside LDH facilitate electron migration and effectively prolong the propagation path of EMW,thereby enhancing conductivity loss.The abundant heterogeneous interfaces between carbon components and metal nanoparticles induce interfacial polarization.In addition,the catalytic activity differences of different metal particles generate different dielectric electromagnetic interfaces,which further promote interfacial polarization.The natural and exchange resonance formed by magnetic particles under a magnetic field provides magnetic losses.Therefore,the successful construction of multiple heterogeneous interfaces effectively enhances the conductivity loss and polarization loss.With a thickness of only 1.4 mm,the composite achieves a minimum reflection loss of-51.8 dB and an effective absorption bandwidth of 4.5 GHz.This work provides an effective strategy for achieving thin thickness and efficient EMW absorption through precise structural design and multi-component construction of absorbers. 展开更多
关键词 Electromagnetic wave absorption Multiple heterogeneous interfaces Conductivity loss Polarization loss
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Differential Resting-State Brain Activity Following Early-and Late-Night Sleep Loss
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作者 Tianqi Di Libo Zhang +6 位作者 Shiqiu Meng Yang Guo Wangyue Liu Enyu Zheng Zhoulong Yu Yan Sun Jie Shi 《Neuroscience Bulletin》 2025年第9期1696-1700,共5页
Dear Editor,Sleep deprivation and loss can have detrimental effects on brain function.Among common patterns of sleep loss are delayed sleep onset(early night sleep loss,EL)and premature awakening(late night sleep loss... Dear Editor,Sleep deprivation and loss can have detrimental effects on brain function.Among common patterns of sleep loss are delayed sleep onset(early night sleep loss,EL)and premature awakening(late night sleep loss,LL).Here,we investigated the distinct impacts of EL and LL on resting-state brain activity.A total of 100 healthy students from several universities in Beijing were recruited and randomly assigned to one of three groups:EL,LL,or full sleep(FS).Restingstate functional magnetic resonance imaging(rs-fMRI)scans were conducted following the sleep manipulations.Compared to the FS group,the LL group showed abnormal low-frequency fluctuation(fALFF)in the prefrontal cortex and insula. 展开更多
关键词 sleep loss sleep deprivation late night sleep loss delayed sleep onset early prefrontal cortex resting state brain activity functional magnetic resonance premature awakening late
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LR-Net:Lossless Feature Fusion and Revised SIoU for Small Object Detection
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作者 Gang Li Ru Wang +5 位作者 Yang Zhang Chuanyun Xu Xinyu Fan Zheng Zhou Pengfei Lv Zihan Ruan 《Computers, Materials & Continua》 2025年第11期3267-3288,共22页
Currently,challenges such as small object size and occlusion lead to a lack of accuracy and robustness in small object detection.Since small objects occupy only a few pixels in an image,the extracted features are limi... Currently,challenges such as small object size and occlusion lead to a lack of accuracy and robustness in small object detection.Since small objects occupy only a few pixels in an image,the extracted features are limited,and mainstream downsampling convolution operations further exacerbate feature loss.Additionally,due to the occlusionprone nature of small objects and their higher sensitivity to localization deviations,conventional Intersection over Union(IoU)loss functions struggle to achieve stable convergence.To address these limitations,LR-Net is proposed for small object detection.Specifically,the proposed Lossless Feature Fusion(LFF)method transfers spatial features into the channel domain while leveraging a hybrid attentionmechanism to focus on critical features,mitigating feature loss caused by downsampling.Furthermore,RSIoU is proposed to enhance the convergence performance of IoU-based losses for small objects.RSIoU corrects the inherent convergence direction issues in SIoU and proposes a penalty term as a Dynamic Focusing Mechanism parameter,enabling it to dynamically emphasize the loss contribution of small object samples.Ultimately,RSIoU significantly improves the convergence performance of the loss function for small objects,particularly under occlusion scenarios.Experiments demonstrate that LR-Net achieves significant improvements across variousmetrics onmultiple datasets compared with YOLOv8n,achieving a 3.7% increase in mean Average Precision(AP)on the VisDrone2019 dataset,along with improvements of 3.3% on the AI-TOD dataset and 1.2% on the COCO dataset. 展开更多
关键词 Small object detection lossless feature fusion attention mechanisms loss function penalty term
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Colossal permittivity and relaxation behavior in LiCuNb_(3)O_(9)-doped CaCu_(3)Ti_(4)O_(12) ceramics with larger electrical response inside grains
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作者 Pu Mao Jie Sun +6 位作者 Hui-Min Feng Zhi-Yong Liu Kun Guo Bing Xie Ting Wang Li-Qiang He Jing-Hui Gao 《Rare Metals》 2025年第8期5689-5702,共14页
Copper calcium titanate(CaCu_(3)Ti_(4)O_(12),CCTO)ceramics with colossal permittivity have gained widespread concern because of their potential application in modern electronic devices with miniaturization and integra... Copper calcium titanate(CaCu_(3)Ti_(4)O_(12),CCTO)ceramics with colossal permittivity have gained widespread concern because of their potential application in modern electronic devices with miniaturization and integration.However,the extent of grain and grain boundary contribution to the colossal permittivity of CCTO-based ceramics based on the internal barrier layer capacitor(IBLC)model is still in debate.This affects their electrical performance optimization and real-world applications.In this study,a series of novel lead-free colossal permittivity ceramic s,xLiCuNb_(3)O_(9-)(1-x)CaCu_(3)Ti_(4)O_(12)(LCNOCCTO),were designed and prepared using a solid-phase reaction approach.The colossal permittivity response mechanism of LCNO-CCTO ceramics was further explored by performing the complex impedance spectrum and analyzing the activation energy from the grain and grain boundary contribution viewpoint.As a result,the LCNO-CCTO ceramics present the cubic perovskite structure with the space groups of■.All the LCNOCCTO ceramics exhibit the significantly enhanced colossal permittivity(10^(5))response,and the ceramic with x=0.15 shows the highest permittivity of about 4.64×10^(5)(20 Hz,room temperature)accompanied by a lower grain resistance of 9.61Ωand larger grain activation energy of 0.21 eV.The enhanced colossal permittivity response is primarily attributed to the great electrical response inside grains of LCNO-CCTO ceramics,resulting from a smaller grain resistance.Also importantly,the high-frequency dielectric relaxation characteristics are improved by incorporating the LCNO into CCTO ceramics as an ion form.Accordingly,the LCNO-CCTO ceramics show a suppressed high-frequency dielectric loss.These results can provide a thorough knowledge and useful optimization strategy for developing high-performance colossal permittivity materials. 展开更多
关键词 CaCu_(3)Ti_(4)O_(12)-based ceramics Colossal permittivity Low dielectric loss Grain boundary resistance
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Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption 被引量:1
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作者 Kaili Zhang Yuefeng Yan +4 位作者 Zhen Wang Guansheng Ma Dechang Jia Xiaoxiao Huang Yu Zhou 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期517-532,共16页
Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)field.Based on the unique energy band ... Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)field.Based on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible solution.Herein,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted strategy.These composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA performance.The results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural distortion.Moreover,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy attenuation.This study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism. 展开更多
关键词 Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching
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基于Focal Loss^(IM)-Transformer的电网虚假数据注入攻击检测
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作者 席磊 和昀 +3 位作者 李子豪 曹利锋 李宗泽 石雨凡 《南方电网技术》 北大核心 2025年第6期26-38,共13页
虚假数据注入攻击对电力信息物理系统造成严重安全威胁。由于受到攻击样本与正常样本之间存在类别不平衡特性,导致机器学习检测方法偏向于多数类的预测,影响其对攻击的检测精度。为此,提出了基于Focal Loss^(IM)-Transformer的虚假数据... 虚假数据注入攻击对电力信息物理系统造成严重安全威胁。由于受到攻击样本与正常样本之间存在类别不平衡特性,导致机器学习检测方法偏向于多数类的预测,影响其对攻击的检测精度。为此,提出了基于Focal Loss^(IM)-Transformer的虚假数据注入攻击检测。Transformer利用其自注意力机制能够捕捉数据中的长期依赖性,进而识别不平衡的虚假数据注入攻击数据。Focal Loss^(IM)通过引入调制因子来更好地匹配虚假数据注入攻击样本的分布和特性,来增强检测方法对不平衡数据的识别能力,以提高检测方法对攻击的检测精度。通过在IEEE 14节点系统、IEEE 30节点系统和IEEE 57节点系统进行仿真,验证了所提方法的有效性。且相较于传统损失函数和其他检测方法,所提方法显示出更好的泛化能力和对少数类的识别能力,且辨识精度高、误报率低。 展开更多
关键词 电力信息物理系统 虚假数据注入攻击 不平衡数据 TRANSFORMER focal loss
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