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Expert consensus on management of instrument separation in root canal therapy
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作者 Yi Fan Yuan Gao +33 位作者 Xiangzhu Wang Bing Fan Zhi Chen Qing Yu Ming Xue Xiaoyan Wang Zhengwei Huang Deqin Yang Zhengmei Lin Yihuai Pan Jin Zhao Jinhua Yu Zhuo Chen Sijing Xie He Yuan Kehua Que Shuang Pan Xiaojing Huang Jun Luo Xiuping Meng Jin Zhang Yi Du Lei Zhang Hong Li Wenxia Chen Jiayuan Wu Xin Xu Jing Zou Jiyao Li Dingming Huang Lei Cheng Tiemei Wang Benxiang Hou Xuedong Zhou 《International Journal of Oral Science》 2025年第3期301-313,共13页
Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate a... Instrument separation is a critical complication during root canal therapy,impacting treatment success and long-term tooth preservation.The etiology of instrument separation is multifactorial,involving the intricate anatomy of the root canal system,instrument-related factors,and instrumentation techniques.Instrument separation can hinder thorough cleaning,shaping,and obturation of the root canal,posing challenges to successful treatment outcomes.Although retrieval of separated instrument is often feasible,it carries risks including perforation,excessive removal of tooth structure and root fractures.Effective management of separated instruments requires a comprehensive understanding of the contributing factors,meticulous preoperative assessment,and precise evaluation of the retrieval difficulty.The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes.The current manuscript provides a framework for understanding the causes,risk factors,and clinical management principles of instrument separation.By integrating effective strategies,endodontists can enhance decision-making,improve endodontic treatment success and ensure the preservation of natural dentition. 展开更多
关键词 root canal therapy instrument separation retrieval techniques tooth preservation root canal therapyimpacting endodontic treatment success root canal root canalposing
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A Canal That Leads to Dialogue
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作者 ZHAO YANG 《China Today》 2025年第9期60-63,共4页
Agroup of young representatives and scholars from more than 10 foreign countries had great fun collecting water samples from the Grand Canal in Sanwan Park,Yangzhou City,east China’s Jiangsu Province,on June 3,2025.T... Agroup of young representatives and scholars from more than 10 foreign countries had great fun collecting water samples from the Grand Canal in Sanwan Park,Yangzhou City,east China’s Jiangsu Province,on June 3,2025.The samples were poured into a“pot of civilization,”which symbolized the integration of cultures.In addition to the canal,the young people also visited places such as Yangzhou University,China Grand Canal Museum,and the Slender West Lake,learning the culture of the Grand Canal and the canal city of Yangzhou. 展开更多
关键词 grand canal young representatives integration culturesin DIALOGUE sanwan park water samples SCHOLARS canal
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Pseudo-psychiatric symptoms of superior semicircular canal dehiscence syndrome
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作者 Quentin Legois Yohan Gallis +5 位作者 Mathieu Marx Olivier Deguine Antoine Yrondi Maximilien Redon Christophe Arbus Valentin Raymond 《General Psychiatry》 2025年第1期68-69,共2页
To the editor:The superior semicircular canal dehiscence was first described by Minor et all in 1998 as a condition in which the superior semicircular canal lacks a bony covering and has gained constantly increasing i... To the editor:The superior semicircular canal dehiscence was first described by Minor et all in 1998 as a condition in which the superior semicircular canal lacks a bony covering and has gained constantly increasing interest since its discovery.2 The symptoms are varied but specific what is known as Minor syndrome or‘third mobile window’syndrome,'as patients may experience autophony with abnormally loud sounds like footsteps,chewing,breathing,eye movement,echoing voice,distortion of environmental sounds and pulsatile tinnitus. 展开更多
关键词 environmental sound distortion superior semicircular canal pulsatile tinnitus environmental sounds superior semicircular canal dehiscence minor syndrome AUTOPHONY
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Evaluation of the Heritage Value Demonstration Degree at the Beijing Tongzhou Grand Canal Heritage Site
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作者 XIAO Yao SUN Shuai +2 位作者 CHEN Yi ZHAO Xinyue CUI Yajia 《Journal of Landscape Research》 2025年第4期39-43,共5页
This study took the Beijing Tongzhou Grand Canal as a case to investigate and evaluate the core section of the Tongzhou Grand Canal.It assessed the historical,artistic,and scientific values embedded in the spatial ent... This study took the Beijing Tongzhou Grand Canal as a case to investigate and evaluate the core section of the Tongzhou Grand Canal.It assessed the historical,artistic,and scientific values embedded in the spatial entity of this cultural heritage and its surrounding environment,as well as the level of its presentation and interpretation.The study culminated in an evaluation of how effectively the heritage values of the Beijing Tongzhou Grand Canal’s spatial heritage are demonstrated.Ultimately,it aimed to provide recommendations and references for the protection and refinement of related cultural heritage spaces,ensuring that the cultural legacy of the Grand Canal’s grain transport system remains enduring and vibrant through time and space. 展开更多
关键词 Tongzhou Grand canal Heritage space Heritage value(s) Grand canal Cultural Belt
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Light-responsive nanomaterials for biofilm removal in root canal treatment 被引量:1
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作者 Di An Mingdong She +5 位作者 Ziyang Zhang Ting Zhang Miaomiao Xu Jinjun Shao Qian Shen Xuna Tang 《Chinese Chemical Letters》 2025年第2期10-20,共11页
Various chemical irrigants and drugs have been employed for intra-canal disinfection in root canal therapy(RCT).However,due to the complexity of root canal anatomy,many drugs still exhibit poor penetrability and antib... Various chemical irrigants and drugs have been employed for intra-canal disinfection in root canal therapy(RCT).However,due to the complexity of root canal anatomy,many drugs still exhibit poor penetrability and antibiotic resistance,leading to suboptimal treatment outcomes.Thus,it is challenging to remove the organic biofilms from root canals.In recent years,light-responsive therapy,with deeper tissue penetration than traditional treatments,has emerged as an effective RCT modality.Herein,this review summarizes the recent development of light-responsive nanomaterials for biofilm removal in RCT.The light-responsive nanomaterials and the corresponding therapeutic methods in RCT,including photodynamic therapy(PDT),photothermal therapy(PTT),and laser-activated therapy,are highlighted.Finally,the challenges that light-responsive nanomaterials and treatment modalities will encounter to conquer the biofilm in future RCT are discussed.This review is believed to significantly accelerate the future development of light-responsive nanomaterials for RCT from bench to bedside. 展开更多
关键词 Light-responsive nanomaterials BIOFILM Root canal treatment Photodynamic therapy Photothermal therapy
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Root canal therapy combined with endoscopic sinus surgery for odontogenic sinusitis:Efficacy comparison in a cohort study
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作者 Jun-Wen Xiao Ping Yu Zhang Zhao 《World Journal of Clinical Cases》 SCIE 2025年第5期13-21,共9页
BACKGROUND Odontogenic maxillary sinusitis,often triggered by dental issues like periapical periodontitis,significantly contributes to chronic sinusitis,mainly affecting adults around 50 years old,emphasizing the need... BACKGROUND Odontogenic maxillary sinusitis,often triggered by dental issues like periapical periodontitis,significantly contributes to chronic sinusitis,mainly affecting adults around 50 years old,emphasizing the need for a multidisciplinary diagnostic and treatment approach.AIM To investigate the therapeutic effect and clinical value of root canal therapy combined with nasal endoscopic surgery compared with simple root canal the-rapy in the treatment of severe odontogenic maxillary sinusitis caused by peria-pical periodontitis.METHODS The clinical data,diagnosis,and treatment of 200 patients with severe odonto-genic maxillary sinusitis caused by periapical periodontitis from October 2020 to October 2021 were analyzed retrospectively.Among them,63 patients were treated with simple root canal therapy as the control group,and 137 patients were treated with root canal therapy combined with nasal endoscopic surgery as the observation group.The therapeutic effect,Lund-Kennedy endoscopic score,paranasal sinus Lund-Mackay score,complication rate,recurrence rate,and patient satisfaction were compared between the two groups.RESULTS First,we compared the effective rates:23 cases were cured,22 were improved,and 8 were ineffective in the control group,yielding a total effective rate of 84.90%.Meanwhile,97 cases were cured,34 improved,and 6 were ineffective in the observation group,resulting in a total effective rate of 95.62%.The observation group had a higher total effective rate compared with the control group(P<0.05).Second,we compared the Lund–Kennedy endoscopic score.Before treatment,no significant difference(P>0.05)was observed in this score between the two groups.After treatment,the Lund–Kennedy endoscopic score decreased in both groups.The Lund–Kennedy endoscopic score of the observation group at 3 and 6 mo after treatment was lower compared to that of the control group(P<0.05).Third,we compared the Lund–Mackay score of paranasal sinuses.Before treatment,there was no significant difference in this score between the two groups(P>0.05).After treatment,the Lund–Mackay scores of paranasal sinuses decreased in both groups.The Lund–Mackay scores of paranasal sinuses in the observation group at 3 and 6 mo after treatment were lower compared to those of the control group(P<0.05).Fourth,we compared the incidence and recurrence rate of complications.Three months after treatment,no significant difference was found in the incidence and recurrence rate of complications between the observation group(6.56%)and the control group(9.52%)(P>0.05).However,6 mo after treatment,the incidence and recurrence rate of complications in the observation group(2.91%)was significantly higher compared to that of the control group(12.69%)(P<0.05).Fifth,we compared patient satisfaction.Six months after treatment,the patient satisfaction of the observation group(93.43%)was significantly better than that of the control group(84.12%)(P<0.05).CONCLUSION Root canal therapy combined with nasal endoscopic surgery has a good therapeutic effect on severe odontogenic maxillary sinusitis caused by periapical periodontitis,and it can reduce the injury of maxillary sinus mucosa and bone,and significantly reduce the incidence of complications and recurrence rate.Meanwhile,it has high patient satisfaction and remarkable therapeutic effect,which is suggested to be popularized and applied in clinic. 展开更多
关键词 Root canal therapy Nasal endoscopic surgery Periapical periodontitis Odontogenic maxillary sinusitis Therapeutic effect Clinical value
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Current status and diversity of fish resources in the Pinglu Canal Century Project
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of... [Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project. 展开更多
关键词 Pinglu canal Project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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Historical, Economical and Environmental Impacts of Suez Canal Connecting the Mediterranean Sea and Red Sea
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作者 Kenneth R. Olson Sergey S. Chernyanskii 《Journal of Water Resource and Protection》 2025年第2期68-95,共28页
The Suez Canal is a unique sea-level waterway between northern Africa and southern Asia that connects the Mediterranean Sea to the Red Sea via the Isthmus of Suez. The canal’s artificial navigation route substantiall... The Suez Canal is a unique sea-level waterway between northern Africa and southern Asia that connects the Mediterranean Sea to the Red Sea via the Isthmus of Suez. The canal’s artificial navigation route substantially reduced the sailing distance between countries in Europe and East Asia and offered a more direct route between the North Atlantic Ocean and the Indian Ocean through the Mediterranean Sea and the Red Sea. The primary objective of this study is to document the historical, economical, and environmental impacts of connecting the Mediterranean Sea and the Red Sea via a canal. After the completion of the Suez Canal in 1869 the canal became an economically lifeline for Egypt. However, the economic gains were partially offset by negative environmental impacts. The impact of port activities on the environment depends on their cargo volume and location, seaports can have an impact on the air quality and therefore on the health of the communities along the Suez Canal. The salinity barrier to migration was removed and animals and plants from the Red Sea began colonizing the eastern Mediterranean. Since the 1880s, species from the Indo-Pacific Ocean have been introduced, via the canal, into the Mediterranean ecosystem. They are endangering some local and endemic species and impacting the ecology. The results showed significant changes in the shoreline and land cover due to climate change and anthropogenic activities that necessitate the implementation of adequate protective measures. The findings of this study may assist policymakers in formulating adaptation plans to protect this crucial area, the communities along the Suez Canal and the Red Sea and Mediterranean ports, from climate change and human activities. 展开更多
关键词 Suez canal EGYPT Mediterranean Sea Red Sea
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Features of the spatial and seasonal distribution of hydrocarbons in water of the North Crimean Canal,Crimea
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作者 O.V.Soloveva E.A.Tikhonova N.Yu.Mirzoeva 《Acta Geochimica》 2025年第2期247-259,共13页
The North Crimean Canal is a watercourse originating from the Kakhovka Reservoir and flowing into the Crimean Peninsula.The canal is an important source of drinking water supply and is also used to irrigate agricultur... The North Crimean Canal is a watercourse originating from the Kakhovka Reservoir and flowing into the Crimean Peninsula.The canal is an important source of drinking water supply and is also used to irrigate agricultural lands and fillfish farms.Due to its location,in recent years its functioning has not been stable,and the processes occurring along the canal have been poorly studied.In this study,we determined the content(with a safety assessment),features of spatial and seasonal distribution,and potential sources of hydrocarbons in the water of the North Crimean Canal,Crimea.During the study period(from March to November 2023)in the primary canal,the content of aliphatic hydrocarbons did not exceed sanitary standards(0.05 mg·L^(-1)).Their increased concentrations in the secondary canals could be associated with the input of organic substances into the canal water as it moves across the Crimean Peninsula.The composition of n-alkanes had temporal and spatial variability.In the period from spring to autumn,the content of autochthonous compounds decreased sharply.The share of allochthonous compounds increased as a consequence of the natural processes.The analysis of biogeochemical markers showed that autochthonous compounds produced by phytoplankton predominated in the spring–summer period.Subsequently,they had less importance,and the main share was accounted for allochthonous n-alkanes. 展开更多
关键词 Aliphatic hydrocarbons N-ALKANES WATER Indexes North Crimean canal CRIMEA
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Canalization of globins in the adaptive evolution of birds
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作者 Xiaojia Zhu Le Yang +5 位作者 Quanjian Tao Xiran Wang Ghulam Nabi Fumin Lei Xiaoping Yu Dongming Li 《Avian Research》 2025年第4期764-774,共11页
The globin superfamily,central to oxygen(O_(2))cascade dynamics,exemplifies how canalization—evolutionary stabilization of phenotypic traits—enables vertebrates to thrive in extreme environments.In birds,hemoglobins... The globin superfamily,central to oxygen(O_(2))cascade dynamics,exemplifies how canalization—evolutionary stabilization of phenotypic traits—enables vertebrates to thrive in extreme environments.In birds,hemoglobins(Hbs)serve as a paradigm of this process,with structural and functional canalization underpinning their exceptional aerobic capacity and elevational diversification.Despite significant advances of globins in our understanding of avian aerobic adaptation,a comprehensive synthesis of functional diversity,molecular evolution,and structural innovation is essential to fully elucidate their canalized roles in O_(2)homeostasis.Integrating perspectives on globin functional diversity and structural evolution,this review examines how chance(mutation/fixation biases)and contingency(historical genetic/epistatic constraints)shape Hb divergence and parallelism,thereby bridging molecular mechanisms with physiological adaptation in birds.We highlight how avian Hbs,canalized through compensatory substitutions and allosteric regulation,achieves a balance between evolutionary robustness and adaptive plasticity.However,critical gaps remain persist:the roles of understudied globins(e.g.,neuroglobin,globin E)and the mechanisms of genetic assimilation in migratory taxa.We propose an integrative framework that incorporates ecological divergence(elevation,flight endurance),phylogenetic timescales,and systems biology to unravel how canalization directs adaptive compromise.By focusing on birds within the amniotes,this synthesis advances a cohesive model for vertebrate evolution,wherein canalized globins reconcile metabolic precision with ecological innovation.Ultimately,this review refines hypotheses of O_(2)cascade evolution and calls for cross-disciplinary studies to decode the genetic and physiological architecture underlying adaptive canalization in extreme environments. 展开更多
关键词 Adaptive evolution Genetic canalization Globin superfamily HEMOGLOBINS Oxygen cascade Structural evolution
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Mandibular left first premolar with three roots and three canals:A case report
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作者 Cheng-Yi Lin Yue-Yuan Yu 《World Journal of Clinical Cases》 2025年第13期20-28,共9页
BACKGROUND The numbers of mandibular first premolar roots and root canals vary,and the incidence of three roots and three canals is 0.09%.CASE SUMMARY In this article,we review the root and root canal conditions for t... BACKGROUND The numbers of mandibular first premolar roots and root canals vary,and the incidence of three roots and three canals is 0.09%.CASE SUMMARY In this article,we review the root and root canal conditions for the mandibular first premolar and report the case of a mandibular left first premolar with three roots and three canals in a male patient,with suggestions for clinical diagnosis and treatment.The patient was referred by an orthodontist for the extraction of the tooth.Preoperative cone-beam computed tomography examination revealed that it had three roots.Under local anesthesia,the extraction socket was carefully expanded,and the tooth was successfully removed intact using forceps.The procedure was uneventful,with no root fractures,postoperative bleeding,or sensory abnormality observed.CONCLUSION The mandibular first premolar is characterized by multiple roots and canal variations that can increase the difficulty of treatment. 展开更多
关键词 Mandibular first premolar Three roots Three root canals Tooth extraction Case report
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Complete resection of recurrent anal canal cancer using endoscopic submucosal dissection and transanal resection: A case report
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作者 Mayuko Kinoshita Tetsuro Maruyama +7 位作者 Shutaro Hike Takuya Hirosuna Shunsuke Kainuma Kazuya Kinoshita Akira Nakano Gaku Ohira Masaya Uesato Hisahiro Matsubara 《World Journal of Gastrointestinal Endoscopy》 2025年第1期54-60,共7页
BACKGROUND Early anal canal cancer is frequently treated with endoscopic submucosal dis-section(ESD)to preserve anal function.However,if the lesion is in the anal canal,then significant difficulties such as bleeding a... BACKGROUND Early anal canal cancer is frequently treated with endoscopic submucosal dis-section(ESD)to preserve anal function.However,if the lesion is in the anal canal,then significant difficulties such as bleeding and challenges associated with scope manipulation can arise.CASE SUMMARY A 70-year-old woman undergoing follow-up after transverse colon cancer surgery was diagnosed with anal canal cancer extending to the dentate line.The patient underwent a combination of ESD and transanal resection(TAR).The specimen was excised in pieces,which resulted in difficulty performing the pathological evaluation of the margins,especially on the anal side where TAR was performed and severe crushing was observed.Careful follow-up was performed,and local recurrence was observed 3 years postoperatively.Because the patient had super-ficial cancer without lymph node metastasis,local resection was performed again.The second treatment attempt was improved as follows:(1)TAR and ESD were performed appropriately based on the situation by the same physician;(2)A needle scalpel was used during TAR to prevent tissue crushing;and(3)The lesion borders were marked using ESD techniques before treatment.Complete resection was performed without complications.CONCLUSION Anal canal lesions can be safely and reliably removed when ESD and TAR are used appropriately. 展开更多
关键词 Anal canal cancer RECURRENCE Endoscopic submucosal dissection Transanal resection Case report
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Fluid Dynamics Research on Erbium Laser-Assisted Chemical Preparation for Root Canal Therapy:A Review
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作者 Kedi Jihu Xinyu He Jizhi Zhao 《Journal of Clinical and Nursing Research》 2025年第4期43-49,共7页
Microbial infection is a principal etiological factor in pulp and periapical diseases,necessitating effective root canal therapy(RCT)for thorough decontamination of the root canal system.However,conventional mechanica... Microbial infection is a principal etiological factor in pulp and periapical diseases,necessitating effective root canal therapy(RCT)for thorough decontamination of the root canal system.However,conventional mechanical and chemical preparation methods remain inadequate,often leaving significant portions of the canal uncleaned and contributing to persistent infection.The advent of erbium laser-assisted chemical preparation has demonstrated significant potential in enhancing root canal disinfection through advanced fluid dynamics mechanisms,particularly cavitation and photoacoustic streaming.This review explores the fundamental principles governing fluid dynamics in erbium laser-assisted irrigation,with a focus on primary and secondary cavitation effects.The interaction between erbium laser energy and water generates vapor bubbles that induce dynamic fluid movement,enhancing the penetration and distribution of irrigants deep within the root canal system.Key factors influencing fluid dynamics intensity,including laser parameters,working tip design,and water medium confinement,are critically analyzed.Furthermore,recent advancements such as Photon-Initiated Photoacoustic Streaming(PIPS),Photoacoustic Synchronized Transients(PHAST),and Shock Wave Enhanced Emission Photoacoustic Streaming(SWEEPS)are reviewed in the context of their ability to improve fluid motion and irrigation efficacy.While these laser-assisted techniques offer promising improvements over traditional methods,challenges remain in optimizing energy parameters and mitigating the constraints imposed by confined root canal environments.Future research should focus on refining fluid dynamics models and conducting clinical studies to validate the efficacy of these innovations.This review aims to provide a comprehensive overview of current developments in fluid dynamics research related to erbium laser-assisted chemical preparation,offering insights into its potential as an advanced modality for root canal disinfection. 展开更多
关键词 Root canal therapy Laser adjunctive therapy Erbium Laser Fluid dynamics Infection control
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Research on the International Communication Path of Intangible Cultural Heritage Short Videos of the Beijing-Hangzhou Grand Canal
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作者 QI Gang 《Journalism and Mass Communication》 2025年第5期284-290,共7页
As a World Cultural Heritage site,the Beijing-Hangzhou Grand Canal has rich intangible cultural heritage(ICH)along its route.In the era of globalization and media convergence,using short videos to promote the canal’s... As a World Cultural Heritage site,the Beijing-Hangzhou Grand Canal has rich intangible cultural heritage(ICH)along its route.In the era of globalization and media convergence,using short videos to promote the canal’s ICH globally is important for internationalizing Chinese culture.This study uses cross-cultural communication theory,case analysis,and data research to examine the current status of short video dissemination of the canal’s ICH.It identifies core challenges in narrative techniques and cultural translation,and proposes a systematic optimization framework with five dimensions including content and platform.The findings offer both theoretical insights and practical guidance for the international promotion of ICH. 展开更多
关键词 Beijing-Hangzhou Grand canal intangible cultural heritage short video international communication
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Biogeochemical behavior of ^(210)Po in the aquatic ecosystem of the North Crimean Canal and adjacent irrigated soils
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作者 A.A.Korotkov N.Yu.Mirzoeva +1 位作者 O.N.Miroshnichenko I.N.Moseichenko 《Acta Geochimica》 2025年第2期314-324,共11页
The main objectives of this study were to investigate the distribution features of the ^(210)Po in abiotic(water and bottom sediments)and biotic(zooplankton,mollusks,fish)components of the North Crimean Canal(NCC)aqua... The main objectives of this study were to investigate the distribution features of the ^(210)Po in abiotic(water and bottom sediments)and biotic(zooplankton,mollusks,fish)components of the North Crimean Canal(NCC)aquatic ecosystem and adjacent irrigated soils as well as assessment of the doses received by water organisms from α-radiation of absorbed ^(210)Po.The samples were processed using standard radiochemical methods accepted in international practice.The activity of ^(210)Po in the samples was measured using the alpha-spectrometric OCTETE Plus complex(ORTEC-AMETEK,USA).The measurement error did not exceed 20%.Activity concentration of ^(210)Po in the studied objects decreased in the following rank:suspended matter(73.6 Bq/kg d.w.)>soils(32.5 Bq/kg d.w.)≈bottom sediments(32.1 Bq/kg d.w.)>mollusks(23.4 Bq/kg w.w.)>fish(6.4 Bq/kg w.w.).The ^(210)Po distribution coefficient(K_(d))values in water between suspended matter and its dissolved parts varied within the 1.4×10^(4)-1.4×10^(5) L/kg range.The concentration factors(CF)of ^(210)Po for hydrobionts of the NCC were in the range 10^(3)-10^(4) L/kg.The calculated absorbed radiation doses from ^(210)Po alpha radiation for the hydrobionts of the North Crimean Canal were significantly below the recommended dose limits. 展开更多
关键词 ^(210)Po North Crimean canal ecosystem Water HYDROBIONTS Bottom sediments Irrigated soils Equivalent dose
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The Guardian of the Grand Canal
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作者 REN DEYONG 《China Today》 2025年第8期60-62,共3页
A precious heritage from ancient times,the Beijing-Hangzhou Grand Canal has renewed its former glory through ecological rehabilitation and cultural preservation over the past decades.
关键词 cultural preservation ecological rehabilitation ancient heritage beijing hangzhou grand canal ecological rehabilitation cultural preservation
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Identity and Reality: Synchronicity of the Grand Canal Culture and Huai'an Historical and Cultural Space
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作者 Xinting LU Shuyuan LV 《Meteorological and Environmental Research》 2025年第1期70-75,共6页
In order to further explore the rich connotation of Huai'an historical and cultural space and the Grand Canal culture,the synchronicity of urban spatial pattern and historical buildings of Huai'an was studied ... In order to further explore the rich connotation of Huai'an historical and cultural space and the Grand Canal culture,the synchronicity of urban spatial pattern and historical buildings of Huai'an was studied under the guidance of synchronic theory and method.It is found that there are the identity and reality law of the development and change of Huai'an historical and cultural space and the Grand Canal cultural system,and it is deduced that there is a spiraling systematic structure chain between the historical and cultural space of Huai'an and the Grand Canal culture,which provides a theoretical reference for promoting the deepening construction of regional culture,the Grand Canal cultural belt and national cultural parks. 展开更多
关键词 Grand canal culture Historical and cultural space Historic buildings SYNCHRONICITY
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Canal Walk架起中外青年文明对话之桥
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作者 赵阳 《今日中国》 2025年第7期28-31,共4页
申遗成功十多年来,中国大运河已经成为一个超级IP,成为外国人探究中华文明的热门场景。站在下一个十年的起点上,Canal Walk顺势而为,以运河为纽带,形成了一个跨越国度、能形成共情的理念和行动。
关键词 中国大运河 canal Walk
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Peat properties of a tropical forest reserve adjacent to a fire-break canal
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作者 Dayang Nur Sakinah Musa Mohd Zahirasri Mohd Tohir +3 位作者 Xinyan Huang Luqman Chuah Abdullah Mohamad Syazaruddin Md Said Muhammad Firdaus Sulaiman 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期155-167,共13页
Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit gr... Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves. 展开更多
关键词 Peat fire Peat properties Fire-break canals Forest reserves
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Steel bar penetrating cervical spinal canal without neurological injury:A case report
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作者 Qin Zhang Tao Ding +1 位作者 Xiao-Feng Gu Yi Liu 《World Journal of Clinical Cases》 SCIE 2024年第17期3214-3220,共7页
BACKGROUND We report a rare case of cervical spinal canal penetrating trauma and review the relevant literatures.CASE SUMMARY A 58-year-old male patient was admitted to the emergency department with a steel bar penetr... BACKGROUND We report a rare case of cervical spinal canal penetrating trauma and review the relevant literatures.CASE SUMMARY A 58-year-old male patient was admitted to the emergency department with a steel bar penetrating the neck,without signs of neurological deficit.Computed tomography(CT)demonstrated that the steel bar had penetrated the cervical spinal canal at the C6–7 level,causing C6 and C7 vertebral body fracture,C6 left lamina fracture,left facet joint fracture,and penetration of the cervical spinal cord.The steel bar was successfully removed through an open surgical procedure by a multidisciplinary team.During the surgery,we found that the cervical vertebra,cervical spinal canal and cervical spinal cord were all severely injured.Postoperative CT demonstrated severe penetration of the cervical spinal canal but the patient returned to a fully functional level without any neurological deficits.CONCLUSION Even with a serious cervical spinal canal penetrating trauma,the patient could resume normal work and life after appropriate treatment. 展开更多
关键词 Cervical spinal canal Penetrating trauma Steel bar Neurological deficit Case report
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