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Development and prospect of near-infrared spectroscopy-assisted schizophrenia diagnosis based on bibliometrics
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作者 Yan Zhang Hao-Yu Xing Juan Yan 《World Journal of Psychiatry》 SCIE 2025年第1期7-11,共5页
In this editorial,we comment on the recent article by Fei et al exploring the field of near-infrared spectroscopy(NIRS)research in schizophrenia from a bibliometrics perspective.In recent years,NIRS has shown unique a... In this editorial,we comment on the recent article by Fei et al exploring the field of near-infrared spectroscopy(NIRS)research in schizophrenia from a bibliometrics perspective.In recent years,NIRS has shown unique advantages in the auxiliary diagnosis of schizophrenia,and the introduction of bibliometrics has provided a macro perspective for research in this field.Despite the opportunities brought about by these technological developments,remaining challenges require multidi-sciplinary approach to devise a reliable and accurate diagnosis system for schizo-phrenia.Nonetheless,NIRS-assisted technology is expected to contribute to the division of methods for early intervention and treatment of schizophrenia. 展开更多
关键词 BIBLIOMETRICS SCHIZOPHRENIA near-infrared spectroscopy Diagnostic technique Data analysis
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Near-infrared brain functional characteristics of mild cognitive impairment with sleep disorders
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作者 Heng Liao Sha Liao +5 位作者 Yu-Jiao Gao Xi Wang Li-Hong Guo Su Zheng Wu Yang Yi-Nan Dai 《World Journal of Psychiatry》 SCIE 2025年第1期106-116,共11页
BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s disease.The disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patie... BACKGROUND Mild cognitive impairment(MCI)has a high risk of progression to Alzheimer’s disease.The disease is often accompanied by sleep disorders,and whether sleep disorders have an effect on brain function in patients with MCI is unclear.AIM To explore the near-infrared brain function characteristics of MCI with sleep disorders.METHODS A total of 120 patients with MCI(MCI group)and 50 healthy subjects(control group)were selected.All subjects underwent the functional near-infrared spec-troscopy test.Collect baseline data,Mini-Mental State Examination,Montreal Cognitive Assessment scale,fatigue severity scale(FSS)score,sleep parameter,and oxyhemoglobin(Oxy-Hb)concentration and peak time of functional near-infrared spectroscopy test during the task period.The relationship between Oxy-RESULTS Compared with the control group,the FSS score of the MCI group was higher(t=11.310),and the scores of Pittsburgh sleep quality index,sleep time,sleep efficiency,nocturnal sleep disturbance,and daytime dysfunction were higher(Z=-10.518,-10.368,-9.035,-10.661,-10.088).Subjective sleep quality and total sleep time scores were lower(Z=-11.592,-9.924).The sleep efficiency of the MCI group was lower,and the awakening frequency,rem sleep latency period,total sleep time,and oxygen desaturation index were higher(t=5.969,5.829,2.887,3.003,5.937).The Oxy-Hb concentration at T0,T1,and T2 in the MCI group was lower(t=14.940,11.280,5.721),and the peak time was higher(t=18.800,13.350,9.827).In MCI patients,the concentration of Oxy-Hb during T0 was negatively correlated with the scores of Pittsburgh sleep quality index,sleep time,total sleep time,and sleep efficiency(r=-0.611,-0.388,-0.563,-0.356).It was positively correlated with sleep efficiency and total sleep time(r=0.754,0.650),and negatively correlated with oxygen desaturation index(r=-0.561)and FSS score(r=-0.526).All comparisons were P<0.05.CONCLUSION Patients with MCI and sleep disorders have lower near-infrared brain function than normal people,which is related to sleep quality.Clinically,a comprehensive assessment of the near-infrared brain function of patients should be carried out to guide targeted treatment and improve curative effect. 展开更多
关键词 MILD Cognitive impairment Sleep disorders near-infrared Brain functional CHARACTERISTICS
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Functional near-infrared spectroscopy in non-invasive neuromodulation 被引量:3
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作者 Congcong Huo Gongcheng Xu +6 位作者 Hui Xie Tiandi Chen Guangjian Shao Jue Wang Wenhao Li Daifa Wang Zengyong Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1517-1522,共6页
Non-invasive cerebral neuromodulation technologies are essential for the reorganization of cerebral neural networks,which have been widely applied in the field of central neurological diseases,such as stroke,Parkinson... Non-invasive cerebral neuromodulation technologies are essential for the reorganization of cerebral neural networks,which have been widely applied in the field of central neurological diseases,such as stroke,Parkinson’s disease,and mental disorders.Although significant advances have been made in neuromodulation technologies,the identification of optimal neurostimulation paramete rs including the co rtical target,duration,and inhibition or excitation pattern is still limited due to the lack of guidance for neural circuits.Moreove r,the neural mechanism unde rlying neuromodulation for improved behavioral performance remains poorly understood.Recently,advancements in neuroimaging have provided insight into neuromodulation techniques.Functional near-infrared spectroscopy,as a novel non-invasive optical brain imaging method,can detect brain activity by measuring cerebral hemodynamics with the advantages of portability,high motion tole rance,and anti-electromagnetic interference.Coupling functional near-infra red spectroscopy with neuromodulation technologies offe rs an opportunity to monitor the cortical response,provide realtime feedbac k,and establish a closed-loop strategy integrating evaluation,feedbac k,and intervention for neurostimulation,which provides a theoretical basis for development of individualized precise neuro rehabilitation.We aimed to summarize the advantages of functional near-infra red spectroscopy and provide an ove rview of the current research on functional near-infrared spectroscopy in transcranial magnetic stimulation,transcranial electrical stimulation,neurofeedback,and braincomputer interfaces.Furthermore,the future perspectives and directions for the application of functional near-infrared spectroscopy in neuromodulation are summarized.In conclusion,functional near-infrared spectroscopy combined with neuromodulation may promote the optimization of central pellral reorganization to achieve better functional recovery form central nervous system diseases. 展开更多
关键词 brain-computer interface cerebral neural networks functional near-infrared spectroscopy neural circuit NEUROFEEDBACK neurological diseases NEUROMODULATION non-invasive brain stimulation transcranial electrical stimulation transcranial electrical stimulation
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Achieving broadband near-infrared luminescence in Cr^(3+)-Activated Y_(2)Mg_(2)Al_(2)Si_(2)O_(12)phosphors via multi-site occupancy 被引量:1
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作者 Gui-Hua Li Han-Qi Wei +4 位作者 Qi-Hua Yang Zhi-Wei Luo Ge-Mei Cai Li Ma Xiao-Jun Wang 《Advanced Powder Materials》 2024年第3期68-76,共9页
Cr^(3+)-activated near-infrared(NIR)phosphors are key for NIR phosphor-converted light emitting diodes(NIR pc-LED).While,the site occupancy of Cr^(3+)is one of the debates that have plagued researchers.Herein,Y2Mg2Al2... Cr^(3+)-activated near-infrared(NIR)phosphors are key for NIR phosphor-converted light emitting diodes(NIR pc-LED).While,the site occupancy of Cr^(3+)is one of the debates that have plagued researchers.Herein,Y2Mg2Al2-Si_(2)O1_(2)(YMAS)with multiple cationic sites is chosen as host of Cr^(3+)to synthesize YMAS:xCr^(3+)phosphors.In YMAS,Cr^(3+)ions occupy simultaneously Al/SiO4 tetrahedral,Mg/AlO6 octahedral,and Y/MgO8 dodecahedral sites which form three luminescent centers named as Cr1,Cr2,and Cr3,respectively.Cr1 and Cr2 relate to an intermediate crystal field,with transitions of^(2)E→^(4)A_(2)and^(4)T_(2)→^(4)A_(2)occurring simultaneously.As Cr^(3+)concentration increases,the^(4)T_(2)→^(4)A_(2)transition becomes more pronounced in Cr1 and Cr2,resulting in a red-shift and broadband emission.Cr3 consistently behaves a weak crystal field and exhibits the broad and long-wavelength emission.Wide-range NIR emission centering at 745 nm is realized in YMAS:0.03Cr^(3+)phosphor.This phosphor has high internal quantum efficiency(IQE?86%)and satisfying luminescence thermal stability(I423 K?70.2%).Using this phosphor,NIR pc-LEDs with 56.6 mW@320 mA optical output power is packaged and applied.Present study not only demonstrates the Cr^(3+)multi-site occupancy in a certain oxide but also provides a reliable approach via choosing a host with diverse cationic sites and local environments for Cr^(3+)to achieve broadband NIR phosphors. 展开更多
关键词 near-infrared phosphor pc-LEDs Cr^(3+) Broadband emission Site occupancy Crystal field
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应用背包和无人机LiDAR数据对森林地上生物量估测
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作者 李馨 岳彩荣 +4 位作者 罗洪斌 张澜钟 沈健 李佳 李初蕤 《东北林业大学学报》 CAS 北大核心 2025年第2期105-113,共9页
激光雷达(LiDAR)技术在林业调查中应用广泛,能够精确获取森林垂直结构信息。利用背包LiDAR结合实地调查样地,验证其替代实地调查的可行性;应用UAV-LiDAR数据,采用多元逐步回归(MSR)、支持向量机(SVM)和随机森林(RF)算法,建立地上生物量... 激光雷达(LiDAR)技术在林业调查中应用广泛,能够精确获取森林垂直结构信息。利用背包LiDAR结合实地调查样地,验证其替代实地调查的可行性;应用UAV-LiDAR数据,采用多元逐步回归(MSR)、支持向量机(SVM)和随机森林(RF)算法,建立地上生物量估测模型并进行对比分析。研究结果显示:(1)在人工干预下,应用背包LiDAR数据提取的单木参数与实测值高度相关,平均胸径的决定系数(R^(2))为0.98,均方根误差(R_(MSE))为0.35 cm;平均树高的R^(2)为0.96,R_(MSE)为0.63 m。(2)应用背包LiDAR构建的生物量样本,利用UAV-LiDAR建立的AGB估测模型中,随机森林模型表现最佳(R^(2)=0.75,R_(MSE)=23.58 t/hm^(2)),其次是支持向量机模型(R^(2)=0.63,R_(MSE)=30.49 t/hm^(2)),多元逐步回归模型表现最差(R^(2)=0.54,R_(MSE)=35.60 t/hm^(2))。因此,背包LiDAR获取的单木胸径及树高精度较高,可替代实测样地生物量,以扩大样本覆盖范围;应用背包LiDAR数据结合机载LiDAR,可实现较大尺度的森林生物量快速估测,为大范围森林生物量反演提供了一种可行方法。 展开更多
关键词 背包激光雷达 无人机激光雷达 森林地上生物量 多元逐步回归 支持向量机 随机森林
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Spatial sensitivity to absorption changes for various near-infrared spectroscopy methods:A compendium review
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作者 Giles Blaney Angelo Sassaroli Sergio Fantini 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第4期1-115,共115页
This compendium review focuses on the spatial distribution of sensitivity to localized absorption changes in optically diffuse media,particularly for measurements relevant to near-infrared spectroscopy.The three tempo... This compendium review focuses on the spatial distribution of sensitivity to localized absorption changes in optically diffuse media,particularly for measurements relevant to near-infrared spectroscopy.The three temporal domains,continuous wave,frequency domain,and time domain,each obtain different optical data types whose changes may be related to effective homogeneous changes in the absorption coefficient.Sensitivity is the relationship between a localized perturbation and the recovered effective homogeneous absorption change.Therefore,spatial sensitivity maps representing the perturbation location can be generated for the numerous optical data types in the three temporal domains.The review first presents a history of the past 30 years of work investigating this sensitivity in optically diffuse media.These works are experimental and theoretical,presenting one-,two-,and three-dimensional sensitivity maps for different Near-Infrared Spectroscopy methods,domains,and data types.Following this history,we present a compendium of sensitivity maps organized by temporal domain and then data type.This compendium provides a valuable tool to compare the spatial sensitivity of various measurement methods and parameters in one document.Methods for one to generate these maps are provided in Appendix A,including the code.This historical review and comprehensive sensitivity map compendium provides a single source researchers may use to visualize,investigate,compare,and generate sensitivity to localized absorption change maps. 展开更多
关键词 Diffuse optics diffusion theory Monte Carlo spatial sensitivity absorption perturbations near-infrared spectroscopy CONTINUOUS-WAVE FREQUENCY-DOMAIN time-domain
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Near-infrared spectroscopy in schizophrenia:A bibliometric perspective
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作者 Xin-Xing Fei Shi-Qi Wang +4 位作者 Ji-Yang Li Zhang-Yu Xu Jian-Xiong Wang Ya-Qian Gao Yue Hu 《World Journal of Psychiatry》 SCIE 2024年第11期1755-1765,共11页
BACKGROUND Compared with current methods used to assess schizophrenia,near-infrared spectroscopy(NIRS)has the advantages of providing noninvasive and real-time monitoring of functional activities of the brain and prov... BACKGROUND Compared with current methods used to assess schizophrenia,near-infrared spectroscopy(NIRS)has the advantages of providing noninvasive and real-time monitoring of functional activities of the brain and providing direct and objective assessment information.AIM To explore the research field of NIRS in schizophrenia from the perspective of bibliometrics.METHODS The Web of Science Core Collection was used as the search tool,and the last search date was April 21,2024.Bibliometric indicators,such as the numbers of publications and citations,were recorded.Bibliometrix and VOS viewer were used for visualization analysis.RESULTS A total of 355 articles from 105 journals were included in the analysis.The overall trend of the number of research publications increased.Schizophrenia Research was identified as an influential journal in the field.Kasai K was one of the most influential and productive authors in this area of research.The University of Tokyo and Japan had the highest scientific output for an institution and a country,respectively.The top ten keywords were“schizophrenia”,“activation”,“near-infrared spectroscopy”,“verbal fluency task”,“cortex”,“brain,performance”,“workingmemory”,“brain activation”,and“prefrontal cortex”.CONCLUSION Our study reveals the evolution of knowledge and emerging trends in the field of NIRS in schizophrenia.the research focus is shifting from underlying disease characteristics to more in-depth studies of brain function and physiological mechanisms. 展开更多
关键词 near-infrared spectroscopy SCHIZOPHRENIA BIBLIOMETRICS Bibliometrix VOS viewer
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Efficacy of multi-color near-infrared fluorescence with indocyanine green:A new imaging strategy and its early experience in laparoscopic cholecystectomy
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作者 Jia-Yi Li Lu Ping +4 位作者 Bo-Zheng Lin Zhi-Hong Wang Chi-Hua Fang Su-Rong Hua Xian-Lin Han 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3703-3709,共7页
BACKGROUND Near-infrared fluorescence imaging via using intravenous indocyanine green(ICG)has a wide range of applications in multiple surgical scenarios.In lapa-roscopic cholecystectomy(LC),it facilitates intraoperat... BACKGROUND Near-infrared fluorescence imaging via using intravenous indocyanine green(ICG)has a wide range of applications in multiple surgical scenarios.In lapa-roscopic cholecystectomy(LC),it facilitates intraoperative identification of the biliary system and reduces the risk of bile duct injury.However,the usual single color fluorescence imaging(SCFI)has limitations in manifesting the fluorescence signal of the target structure when its intensity is relatively low.Moreover,sur-geons often experience visual fatigue.We hypothesized that a novel imaging stra-tegy,named multi-color fluorescence imaging(MCFI),could potentially address these issues by decreasing hepatic and background fluorescence pollution and improving biliary visualization.AIM To investigate the novel imaging strategy MCFI in LC.METHODS This was a single-center retrospective study conducted at Peking Union Medical College Hospital,Beijing,China.Patients who underwent LC from June 2022 to March 2023 by the same surgical team were enrolled.Demographic features,clinical and surgical information were collected.The clarity,visual comfort,and effectiveness of different imaging strategies were subjectively evaluated by surgeons.RESULTS A total of 155 patients were included,60 patients were in the non-ICG group in which only bright light illuminance without ICG was applied,60 patients were in the SCFI group,and 35 patients were in the MCFI group.No statist-ically significant differences were found in demographics or clinical history.Post-surgical complications were minimal in all 3 groups with no significant differences observed.MCFI improved the clarity of imaging and visual comfort.Clarity of imaging and visual comfort were improved with MCFI.CONCLUSION MCFI improves biliary visualization and reduces liver fluorescence contamination,which supports its routine use in LC.MCFI may also be a better choice than SCFI in other clinical settings. 展开更多
关键词 Indocyanine green near-infrared fluorescence Fluorescence imaging Multi-color fluorescence imaging Laparoscopic cholecystectomy
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A highly sensitive ratiometric near-infrared nanosensor based on erbium-hyperdoped silicon quantum dots for iron(Ⅲ) detection
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作者 Kun Wang Wenxuan Lai +2 位作者 Zhenyi Ni Deren Yang Xiaodong Pi 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期49-58,共10页
Ratiometric fluorescent detection of iron(Ⅲ)(Fe^(3+))offers inherent self-calibration and contactless analytic capabilities.However,realizing a dual-emission near-infrared(NIR)nanosensor with a low limit of detection... Ratiometric fluorescent detection of iron(Ⅲ)(Fe^(3+))offers inherent self-calibration and contactless analytic capabilities.However,realizing a dual-emission near-infrared(NIR)nanosensor with a low limit of detection(LOD)is rather challenging.In this work,we report the synthesis of water-dispersible erbium-hyperdoped silicon quantum dots(Si QDs:Er),which emit NIR light at the wavelengths of 810 and 1540 nm.A dual-emission NIR nanosensor based on water-dispersible Si QDs:Er enables ratiometric Fe^(3+)detection with a very low LOD(0.06μM).The effects of pH,recyclability,and the interplay between static and dynamic quenching mechanisms for Fe^(3+)detection have been systematically studied.In addition,we demonstrate that the nanosensor may be used to construct a sequential logic circuit with memory functions. 展开更多
关键词 erbium-hyperdoped silicon quantum dots dual-emission near-infrared nanosensor Fe^(3+)detection sequential logic circuit
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Cortical activity in patients with high-functioning ischemic stroke during the Purdue Pegboard Test:insights into bimanual coordinated fine motor skills with functional near-infrared spectroscopy
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作者 Siyun Chen Mengchai Mao +4 位作者 Guangyue Zhu Yufeng Chen Yuqi Qiu Bin Ye Dongsheng Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1098-1104,共7页
After stroke,even high-functioning individuals may experience compromised bimanual coordination and fine motor dexterity,leading to reduced functional independence.Bilateral arm training has been proposed as a promisi... After stroke,even high-functioning individuals may experience compromised bimanual coordination and fine motor dexterity,leading to reduced functional independence.Bilateral arm training has been proposed as a promising intervention to address these deficits.However,the neural basis of the impairment of functional fine motor skills and their relationship to bimanual coordination performance in stroke patients remains unclear,limiting the development of more targeted interventions.To address this gap,our study employed functional near-infrared spectroscopy to investigate cortical responses in patients after stroke as they perform functional tasks that engage fine motor control and coordination.Twenty-four high-functioning patients with ischemic stroke(7 women,17 men;mean age 64.75±10.84 years)participated in this cross-sectional observational study and completed four subtasks from the Purdue Pegboard Test,which measures unimanual and bimanual finger and hand dexterity.We found significant bilateral activation of the sensorimotor cortices during all Purdue Pegboard Test subtasks,with bimanual tasks inducing higher cortical activation than the assembly subtask.Importantly,patients with better bimanual coordination exhibited lower cortical activation during the other three Purdue Pegboard Test subtasks.Notably,the observed neural response patterns varied depending on the specific subtask.In the unaffected hand task,the differences were primarily observed in the ipsilesional hemisphere.In contrast,the bilateral sensorimotor cortices and the contralesional hemisphere played a more prominent role in the bimanual task and assembly task,respectively.While significant correlations were found between cortical activation and unimanual tasks,no significant correlations were observed with bimanual tasks.This study provides insights into the neural basis of bimanual coordination and fine motor skills in high-functioning patients after stroke,highlighting task-dependent neural responses.The findings also suggest that patients who exhibit better bimanual performance demonstrate more efficient cortical activation.Therefore,incorporating bilateral arm training in post-stroke rehabilitation is important for better outcomes.The combination of functional near-infrared spectroscopy with functional motor paradigms is valuable for assessing skills and developing targeted interventions in stroke rehabilitation. 展开更多
关键词 bilateral arm training bimanual coordination cortical activity fine motor dexterity functional near-infrared spectroscopy(fNIRS) high-functioning Purdue Pegboard Test stroke
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Near-infrared cholangiography with intragallbladder indocyanine green injection in minimally invasive cholecystectomy
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作者 Savvas Symeonidis Ioannis Mantzoros +9 位作者 Elissavet Anestiadou Orestis Ioannidis Panagiotis Christidis Stefanos Bitsianis Vasiliki Bisbinas Konstantinos Zapsalis Trigona Karastergiou Dimitra Athanasiou Stylianos Apostolidis Stamatios Angelopoulos 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第4期1017-1029,共13页
Laparoscopic cholecystectomy(LC)remains one of the most commonly performed procedures in adult and paediatric populations.Despite the advances made in intraoperative biliary anatomy recognition,iatrogenic bile duct in... Laparoscopic cholecystectomy(LC)remains one of the most commonly performed procedures in adult and paediatric populations.Despite the advances made in intraoperative biliary anatomy recognition,iatrogenic bile duct injuries during LC represent a fatal complication and consist an economic burden for healthcare systems.A series of methods have been proposed to prevent bile duct injury,among them the use of indocyanine green(ICG)fluorescence.The most commonly reported method of ICG injection is the intravenous administration,while literature is lacking studies investigating the direct intragallbladder ICG injection.This narrative mini-review aims to assess the potential applications,usefulness,and limitations of intragallbladder ICG fluorescence in LC.Authors screened the available international literature to identify the reports of intragallbladder ICG fluorescence imaging in minimally invasive cholecystectomy,as well as special issues regarding its use.Literature search retrieved four prospective cohort studies,three case-control studies,and one case report.In the three case-control studies selected,intragallbladder near-infrared cholangiography(NIRC)was compared with standard LC under white light,with intravenous administration of ICG for NIRC and with standard intraoperative cholangiography(IOC).In total,133 patients reported in the literature have been administered intragallbladder ICG administration for biliary mapping during LC.Literature includes several reports of intragallbladder ICG administration,but a standardized technique has not been established yet.Published data suggest that NIRC with intragallbladder ICG injection is a promising method to achieve biliary mapping,overwhelming limitations of IOC including intervention and radiation exposure,as well as the high hepatic parenchyma signal and time interval needed in intravenous ICG fluorescence.Evidence-based guidelines on the role of intragallbladder ICG fluorescence in LC require the assessment of further studies and multicenter data collection into large registries. 展开更多
关键词 Minimally invasive cholecystectomy Laparoscopic cholecystectomy Biliary tract mapping Indocyanine green near-infrared fluorescent cholangiography Intracystic indocyanine green Intragallbladder indocyanine green Bile duct injury
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Suppressing neuroinflammation using the near-infrared light emitted by (Sr,Ba)Ga_(12)O_(19): Cr^(3+) phosphor
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作者 Qi Liu Fangmei Yu +5 位作者 Hossein Chamkouri Yanguang Guo Ping Chen Bo Wang Dongwei Liu Lei Chen 《Advanced Photonics Nexus》 2024年第3期68-80,共13页
Neurodegenerative diseases,such as Parkinson’s and Alzheimer’s diseases,affect the elderly worldwide and will become more prevalent as the global population ages.Neuroinflammation is a common characteristic of neuro... Neurodegenerative diseases,such as Parkinson’s and Alzheimer’s diseases,affect the elderly worldwide and will become more prevalent as the global population ages.Neuroinflammation is a common characteristic of neurodegenerative diseases.By regulating the phenotypes of microglia,it is possible to suppress neuroinflammation and,in turn,help prevent neurodegenerative diseases.We report a noninvasive photonic approach to regulating microglia from overexcited M1/M2 to the resting M0 phenotype using a special near-infrared(NIR)light emitted by the SrGa_(12)O_(19)∶Cr^(3t) phosphor.The absorbance and internal and external quantum efficiencies of the optimal SreGa_(0.99)Cr_(0.01)_(12)O_(19) phosphor synthesized at 1400℃ for 8 h using 1%H_(3)BO_(3) t 1%AlF3 as flux are 53.9%,99.2%,and 53.5%;the output power and energyconversion efficiency of the LED device packaged using the optimal SrGa_(12)O_(19): Cr^(3+) phosphor driven at 20 mA reach unprecedentedly 19.69 mW and 37.58%,respectively.The broadband emission of the NIR LED device covers the absorption peaks of cytochrome c oxidase well,and the NIR light can efficiently promote the proliferation of microglia,produce adenosine triphosphate(ATP),reverse overexcitation,alleviate and inhibit inflammation,and improve cell survival rate and activity,showing great prospects for photomedicine application. 展开更多
关键词 near-infrared light LED SrGa_(12)O_(19):Cr^(3+)phosphor PHOTOBIOMODULATION NEUROINFLAMMATION microglia.
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智航无人机载LiDAR系统在轨道交通建设中的应用分析 被引量:1
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作者 徐花芝 蒋文婷 +2 位作者 陈春雷 张允涛 王萧 《测绘通报》 CSCD 北大核心 2024年第2期178-182,共5页
为了减少轨道交通建设外业勘测的工作量,提高制图的效率和精度,本文首先基于实际项目,选用智航SF1650六旋翼无人机载LiDAR系统对济南新东站片区进行航摄,利用获取的LiDAR点云和影像数据制作DEM、DOM,然后再进行大比例尺地形图和片区断... 为了减少轨道交通建设外业勘测的工作量,提高制图的效率和精度,本文首先基于实际项目,选用智航SF1650六旋翼无人机载LiDAR系统对济南新东站片区进行航摄,利用获取的LiDAR点云和影像数据制作DEM、DOM,然后再进行大比例尺地形图和片区断面图的制作。通过外业勘测核实,DEM和DOM精度完全满足轨道交通建设工程制作大比例尺地形图的要求,且相较于传统立体航测,精度和数据利用率得到很大的提升,极大减少了外业勘测工作量,验证了智航SF1650无人机载LiDAR系统的可行性,为今后的工程应用提供了参考方案。 展开更多
关键词 智航SF1650无人机 lidar点云 轨道交通建设 精度高
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PREPARATION AND CHARACTERIZATION OF WATER-SOLUBLE NEAR-INFRARED EMITTING PbS QUANTUM DOTS
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作者 曹洁 李杉 +1 位作者 邓大伟 顾月清 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第1期81-87,共7页
A new facile method for preparing water-soluble near-infrared (NIR)-emitting PbS quantum dots (QDs) is proposed by using N-acetyl-L-cysteine (NAC, a derivate of L-cysteine) as its stabilizer. The influence of th... A new facile method for preparing water-soluble near-infrared (NIR)-emitting PbS quantum dots (QDs) is proposed by using N-acetyl-L-cysteine (NAC, a derivate of L-cysteine) as its stabilizer. The influence of the precursor Pb/S molar ratio, the Pb/NAC molar ratio, and the pH of original solution on optical properties is explored. Results show that aqueous PbS QDs with strong NIR fluorescence can be prepared and their photoluminescence emission peaks can be tuned from 895 nm to 970 nm. Studies indicate that such aqueous QDs have a potential application in biomedical imaging, especially in noninvasive in vivo fluorescence imaging. In addition, the resulting PbS QDs are further characterized by a transmission electron microscopy and X-ray diffraction analysis. 展开更多
关键词 semiconductor quantum dots (QDs) biomedical imaging N-acetyl-L-cystelne(NAC) near-infrared
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基于机载LiDAR技术植被茂密区小型滑坡识别与评价
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作者 陈刚 郝社锋 +4 位作者 蒋波 喻永祥 车增光 刘汉湖 杨容浩 《自然资源遥感》 CSCD 北大核心 2024年第3期196-205,共10页
山体滑坡会导致生命和财产损失,获取完整的滑坡空间分布图及对易发区域的准确判定有利于指导生产、生活和生态空间优化。在滑坡调查过程中,茂密的植被覆盖使滑坡调查难度加大,机载激光雷达(light detection and ranging,LiDAR)技术的穿... 山体滑坡会导致生命和财产损失,获取完整的滑坡空间分布图及对易发区域的准确判定有利于指导生产、生活和生态空间优化。在滑坡调查过程中,茂密的植被覆盖使滑坡调查难度加大,机载激光雷达(light detection and ranging,LiDAR)技术的穿透能力使真实地形特征得以呈现,从而实现植被茂密区滑坡识别。该文通过仿地飞行获取研究区LiDAR点云数据,基于点云数据得到数字高程模型(digital elevation model,DEM),在山体阴影分析、彩色增强显示及三维场景模拟基础上,识别出区域内已有滑坡的位置与规模,经野外核实,滑坡解译精度为86.4%。针对滑坡易发区评价问题,以现有滑坡为样本,首次采用遥感分类思维开展滑坡易发区划定,采用小区域内与滑坡发育有关的高程、坡度和地表起伏度组合成影像,以支持向量机为分类方法,判定出滑坡易发区域,经滑坡检验样本分析,滑坡识别精度为81.91%。研究表明:基于高精度的LiDAR数据及其视觉增强后的图像能识别小型滑坡,采用支持向量机分类法可以准确确定滑坡易发区,为下一步三生空间规划与优化提供依据。 展开更多
关键词 lidar 滑坡 山体阴影 支持向量机 滑坡易发性评价
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基于RS-Conv的多尺度神经网络LiDAR点云断裂带提取方法
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作者 宋冬梅 王浩 +2 位作者 冯家兴 单新建 王斌 《地震地质》 EI CSCD 北大核心 2024年第3期739-755,共17页
断裂带与地震、滑坡等自然灾害的发生有着密切关系,精准提取断裂带不仅可为地震断层的定量化研究提供指导,还可为地震灾害风险评估及防震减灾决策的制定提供科学依据。针对现有方法中LiDAR点云断裂带提取不完整、连续性差及错误率高等问... 断裂带与地震、滑坡等自然灾害的发生有着密切关系,精准提取断裂带不仅可为地震断层的定量化研究提供指导,还可为地震灾害风险评估及防震减灾决策的制定提供科学依据。针对现有方法中LiDAR点云断裂带提取不完整、连续性差及错误率高等问题,文中提出了一种基于RS-Conv的多尺度神经网络LiDAR点云断裂带提取方法,以便更好地解决复杂地形区域的断裂带自动提取问题。该方法首先构建不同空间尺度的邻域点集,从而更全面地考察点云的局部几何结构特征。考虑到RS-Conv算子能够很好地表征中心点与邻域点的空间关系,文中以RS-Conv算子作为卷积模块构建了多尺度神经网络模型,以提取出LiDAR点云不同尺度的深层次特征,对其进行堆叠并输入到全连接层,以完成对断裂带点的提取。最后,在ISPRS点云数据集、川滇点云数据集和鲜水河数据集上对文中所述方法与张量分解方法和Deep Neural Networks(DNN)方法进行了对比实验,结果表明,文中方法的分类精度最高,分类总误差最低仅为0.3%,较其他方法降低了0.91%~2.79%,证实了该方法在点云断裂带提取方面的优越性。 展开更多
关键词 lidar点云 多尺度邻域点集 深度学习 断裂带提取
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基于IMU-LiDAR紧耦合的煤矿防冲钻孔机器人定位导航方法 被引量:4
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作者 司垒 王忠宾 +4 位作者 魏东 顾进恒 闫海峰 谭超 朱远胜 《煤炭学报》 EI CAS CSCD 北大核心 2024年第4期2179-2194,共16页
防冲钻孔机器人是冲击地压矿井卸压的关键设备,其在复杂卸压巷道的精确地图构建和的稳定导航是实现钻孔作业智能化的基础和前提。在分析激光雷达点云畸变成因和同步定位与地图构建(SLAM)算法缺陷的基础上,设计了基于惯性测量单元(IMU)... 防冲钻孔机器人是冲击地压矿井卸压的关键设备,其在复杂卸压巷道的精确地图构建和的稳定导航是实现钻孔作业智能化的基础和前提。在分析激光雷达点云畸变成因和同步定位与地图构建(SLAM)算法缺陷的基础上,设计了基于惯性测量单元(IMU)连续时间轨迹的点云畸变矫正方法,建立了激光雷达和IMU的数据融合模型,提出了基于IMU-LiDAR紧耦合的防冲钻孔机器人定位建图方法。根据煤矿卸压巷道特点建立了密闭坡道模型,开展了建图效果仿真分析,结果表明,所提算法在定位精度、轨迹误差方面均优于现有常用算法。在此基础上,设计了基于改进人工势场法和快速扩展随机树的动态路径规划方法,建立了适用于防冲钻孔机器人的路径规划与导航融合方案,并设计了2种仿真运动场景,结果表明,所提路径规划方法在全局路径规划和动态路径规划的平均路径长度、平均运行时间、平均生成节点数等方面均具有较好的综合性能。为了进一步验证防冲钻孔机器人定位导航方法的实用性,在校内模拟巷道、地面实验基地和井下卸压巷道等场景下开展了多组对比实验,结果表明:将IMU数据与LiDAR数据紧耦合后,所提方法的定位建图精度明显提高,在特征退化场景中具有优越的定位建图性能,且规划路径的运算效率和路径代价方面均具有良好的表现,验证了所提定位导航方法在多种场景中的可行性和优越性。 展开更多
关键词 防冲钻孔机器人 同步定位与地图构建 惯性-雷达融合 定位导航 路径规划
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一种DEM辅助下的LiDAR点云PTD滤波改进算法
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作者 郑斌 邹学忠 李小昱 《地理空间信息》 2024年第1期13-15,28,共4页
针对传统渐进加密不规则三角网(PTD)滤波算法在复杂地形环境下需要反复调试地面点判断参数才能获得较好结果的局限性,以往期DEM数据提取的地形高程和地形梯度为辅助,改进PTD中初始地面种子点的选取方法,优化地面点判断参数,并对往期DEM... 针对传统渐进加密不规则三角网(PTD)滤波算法在复杂地形环境下需要反复调试地面点判断参数才能获得较好结果的局限性,以往期DEM数据提取的地形高程和地形梯度为辅助,改进PTD中初始地面种子点的选取方法,优化地面点判断参数,并对往期DEM数据和现势LiDAR点云数据之间的地形变化进行检测和处理,适用于不同坡度地形条件的复杂地形,滤波效果较好。对比分析实验数据精度可知,该算法能有效降低I类与II类误差,且样本分类精度均在90%以上,说明DEM辅助可切实提高PTD滤波算法的精度。 展开更多
关键词 lidar点云 PTD滤波 DEM辅助分类
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改进的密度聚类精确自适应提取LiDAR电力线点云方法
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作者 纪凯 武永彩 《安徽职业技术学院学报》 2024年第1期26-30,85,共6页
原有邻域半径r_(Eps)与密度阈值p_(MinPts)两个参数的初始赋值导致电力线点云的提取结果存在不确定性,在密度聚类的基础上增添了点云簇类自适应判别方法,该方法避免人员重复测试初始参数的繁琐过程,采用C++语言完成了对该算法电力线精... 原有邻域半径r_(Eps)与密度阈值p_(MinPts)两个参数的初始赋值导致电力线点云的提取结果存在不确定性,在密度聚类的基础上增添了点云簇类自适应判别方法,该方法避免人员重复测试初始参数的繁琐过程,采用C++语言完成了对该算法电力线精确提取及电力线拟合程序的开发与测试。结果表明:改进后的密度聚类法在电力线点云提取的损失率仅0.02%,三维重建残差为0.213 m;该方法大幅提高了电力线点云提取的准确性与便捷性,适用于高压电力走廊的电力巡检与三维重建等工作。 展开更多
关键词 机载lidar 点云数据 密度聚类 自适应 三维重建
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机载LiDAR和模糊推理系统在黄土高原土壤侵蚀监测中的应用
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作者 邱春霞 刘晓宏 +2 位作者 李豆 张佳淼 李朋飞 《干旱区研究》 CSCD 北大核心 2024年第8期1331-1342,共12页
黄土高原是我国乃至全球土壤侵蚀最严重的地区之一,受限于监测技术,黄土高原土壤侵蚀的研究多集中于径流小区尺度,大规模的侵蚀研究和野外观测仍相对缺乏。机载激光雷达(LiDAR)技术的革新为高精度、大规模土壤侵蚀研究提供了新的可能。... 黄土高原是我国乃至全球土壤侵蚀最严重的地区之一,受限于监测技术,黄土高原土壤侵蚀的研究多集中于径流小区尺度,大规模的侵蚀研究和野外观测仍相对缺乏。机载激光雷达(LiDAR)技术的革新为高精度、大规模土壤侵蚀研究提供了新的可能。然而,该技术受复杂地形的影响会产生高程不确定性误差,导致其监测土壤侵蚀的能力缺乏深入研究。基于此,本文以我国黄土高原丘陵沟壑区典型小流域桥沟流域为研究对象,联合机载Li-DAR测量和模糊推理系统(FIS),定量分析了两期DEM求差(DoD)不确定性的空间分布,研究小流域土壤侵蚀与沉积的空间分布特征。结果表明:(1)地形形态、点云密度等对插值生成的DEM误差影响较大,地形平坦区域的DoD不确定性明显小于地形陡峭区域的DoD不确定性;(2)FIS算法通过将已知的误差源整合到一个稳定的误差模型中,减少了主观干预和人为误差,避免了在复杂的DEM表面对误差进行错误估计,提高了计算结果的准确性;(3)梁峁坡地区侵蚀产沙体积为9.21m^(3),占坡沟系统产沙体积的15.89%;沟谷坡地区侵蚀严重,侵蚀产沙体积为48.76m^(3),占坡沟系统产沙体积的84.11%,在坡沟系统的产沙中起主导作用。沟床地区主要以沉积为主,梁峁坡和沟谷坡对侵蚀产沙贡献较大,而沟床则主要为产沙沉积区。研究成果不仅为黄土高原小流域的土壤侵蚀监测技术的拓展提供了新的视角,也为实施有效的水土保持措施提供了理论依据和参考。 展开更多
关键词 机载lidar 土壤侵蚀监测 DoD不确定性 模糊推理系统 黄土高原
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