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Associations of lifestyle and diet with the risk of nasopharyngeal carcinoma in Singapore:a case–control study 被引量:12
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作者 Sook Kwin Yong Tam Cam Ha +3 位作者 Ming Chert Richard Yeo Valerie Gaborieau James D.McKay Joseph Wee 《Chinese Journal of Cancer》 SCIE CAS CSCD 2017年第2期63-70,共8页
Background: Nasopharyngeal carcinoma(NPC) is a commonly diagnosed cancer in Southeast Asia. Many studies have examined the risk factors for NPC, yet the roles of some risk factors remain inconclusive. The purpose of t... Background: Nasopharyngeal carcinoma(NPC) is a commonly diagnosed cancer in Southeast Asia. Many studies have examined the risk factors for NPC, yet the roles of some risk factors remain inconclusive. The purpose of this study was to examine associations between modifiable lifestyle factors and the risk of NPC in the Singaporean population.Methods: We conducted a case–control study in Singapore with 300 patients and 310 controls who were recruited between 2008 and 2012. Each control was selected and individually matched to each patient based on sex, ethnicity, and age(±5 years). A total of 290 pairs of cases and controls were matched successfully. We examined lifestyle factors such as tobacco smoking, alcohol drinking, various salted and preserved food consumption, and weaning practices.Results: After adjusting for covariates, multivariate analysis showed that those participants who were current smokers and had ever smoked tobacco had a higher risk of NPC than participants who had never smoked, with odds ratios(ORs) of 4.50(95% confidence interval [CI] 2.58–7.86; P < 0.001) and 2.52(95% CI 1.54–4.12; P < 0.001), respectively. Those who consumed salted vegetables at least once a week also showed a significantly increased risk of NPC than those who never or rarely consumed salted vegetables, with an OR of 4.18(95% CI 1.69–10.38; P = 0.002).Conclusion: Smoking(currently and ever-smoked) and consuming salted vegetables once a week or more were lifestyle risk factors for NPC, and changes of these factors for the better may reduce the risk of NPC. 展开更多
关键词 Nasopharyngeal carcinoma DIET SMOKING Alcohol drinking case–control study Preserved food
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Blood Pressure Profile and Glycemic Control of Type 2 Diabetics and Hypertensives at the Yalgado Ouedraogo University Hospital: A Review of 116 Cases
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作者 G. R. C. Millogo A. Thiam +6 位作者 Y. Kambiré E. Nongkouni S. E. Dabiré L. J. Kagambéga J. K. Kologo V. N. Yaméogo P. Zabsonré 《World Journal of Cardiovascular Diseases》 CAS 2024年第1期61-76,共16页
Objective: The association hypertension and diabetes is important. The two pathologies may influence each other. The aim was to study the correlation between glycemic control and blood pressure control and to determin... Objective: The association hypertension and diabetes is important. The two pathologies may influence each other. The aim was to study the correlation between glycemic control and blood pressure control and to determine the factors associated with blood pressure control. Methodology: This was a descriptive cross-sectional study with an analytical focus over 7 months. Patients were recruited as outpatients and all underwent ambulatory blood pressure measure, glycated hemoglobin and creatinine measurements, and assessment of compliance with treatment. Results: During this period 116 patients were collected. The predominance was female 69%. The mean age of the patients was 62 ± 7 years with a peak between 60 and 70 years. The average age of hypertension was 12 years and that of diabetes 6 1/2 years. The most frequently associated cardiovascular risk factor was a sedentary lifestyle (71.5%) after age. 57.8% of patients were not controlled at the office, with a predominance of systolic hypertension (58.2%). 61.6% of patients were controlled by ambulatory blood pressure measure, a rate of 47.8% of white coat hypertension. Glycemic control was observed in 42.2% of cases and 87% of patients had good renal function (glomerular filter rate ≥ 60 ml/mn). Therapeutic compliance was good in 53.4% of cases and dual therapy was the most used therapeutic modality 44.8% (52 patients) followed by triple therapy. The factors associated with poor blood pressure control were glycemic imbalance, non-compliance and monotherapy. Dual therapy had a protective effect. Conclusion: The association of hypertension and type 2 diabetes is frequent. The risk of occurrence increases with age. Ambulatory blood pressure measure is the best method to assess blood pressure control. Optimization of blood pressure control should also include optimization of glycemic control. 展开更多
关键词 Blood Pressure control Glycemic control Hypertensive and Diabetic Patients
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Efficacy of borneol-gypsum in skin regeneration and pain control in toxic epidermal necrolysis:A case report
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作者 Lu-Wei Yang Li-Juan Zhang +7 位作者 Bin-Bin Zhou Xin-Yu Lin Yu-Ting Chen Xiao-Yu Qin Hui-Ying Tian Li-Li Ma Ying Sun Lin-Di Jiang 《World Journal of Clinical Cases》 SCIE 2024年第7期1290-1295,共6页
BACKGROUND Toxic epidermal necrolysis(TEN)is a life-threatening dermatological emergency mainly induced by drug hypersensitivity reactions.Standard management includes discontinuation of culprit drug and application o... BACKGROUND Toxic epidermal necrolysis(TEN)is a life-threatening dermatological emergency mainly induced by drug hypersensitivity reactions.Standard management includes discontinuation of culprit drug and application of immunomodulatory therapy.However,mortality remains high due to complications like septic shock and multiorgan failures.Innovative approaches for skin care are crucial.This report introduces borneol-gypsum,a traditional Chinese drug but a novel dressing serving as an adjuvant of TEN therapy,might significantly improve skin conditions and patient outcomes in TEN.CASE SUMMARY A 38-year-old woman diagnosed with eosinophilic granulomatosis with polyangiitis experienced gangrenous complications and motor nerve involvement.After initial treatment of high-dose corticosteroids and cyclophosphamide,symptom of foot drop improved,absolute eosinophil counts decreased,while limb pain sustained.Duloxetine was added to alleviate her symptom.Subsequently,TEN developed.Additional topical application of borneol-gypsum dressing not only protected the skin lesions from infection but also significantly eased localized pain.This approach demonstrated its merit in TEN management by promoting skin healing and potentially reducing infection risks.CONCLUSION Borneol-gypsum dressing is a promising adjuvant that could significantly improve TEN management,skin regeneration,and patient comfort. 展开更多
关键词 Toxic epidermal necrolysis Eosinophilic granulomatosis with polyangiitis DULOXETINE BORNEOL GYPSUM case report
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Propofol sedation in routine endoscopy:A case series comparing target controlled infusion vs manually controlled bolus concept
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作者 Riad Sarraj Lorenz Theiler +2 位作者 Nima Vakilzadeh Niklas Krupka Reiner Wiest 《World Journal of Gastrointestinal Endoscopy》 2024年第1期11-17,共7页
BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPS)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedatio... BACKGROUND Many studies have addressed safety and effectiveness of non-anaesthesiologist propofol sedation(NAPS)for gastrointestinal(GI)endoscopy Target controlled infusion(TCI)is claimed to provide an optimal sedation regimen by avoiding under-or oversedation.AIM To assess safety and performance of propofol TCI sedation in comparison with nurse-administered bolus-sedation.METHODS Fouty-five patients undergoing endoscopy under TCI propofol sedation were prospectively included from November 2016 to May 2017 and compared to 87 patients retrospectively included that underwent endoscopy with NAPS.Patients were matched for age and endoscopic procedure.We recorded time of sedation and endoscopy,dosage of medication and adverse events.RESULTS There was a significant reduction in dose per time of propofol administered in the TCI group,compared to the NAPS group(8.2±2.7 mg/min vs 9.3±3.4 mg/min;P=0.046).The time needed to provide adequate sedation levels was slightly but significantly lower in the control group(5.3±2.7 min vs 7.7±3.3 min;P<0.001),nonetheless the total endoscopy time was similar in both groups.No differences between TCI and bolus-sedation was observed for mean total-dosage of propofol rate as well as adverse events.CONCLUSION This study indicates that sedation using TCI for GI endoscopy reduces the dose of propofol necessary per minute of endoscopy.This may translate into less adverse events.However,further and randomized trials need to confirm this trend. 展开更多
关键词 SEDATION ENDOSCOPY PROPOFOL Target controlled infusion Non-anaesthesiologist propofol sedation Adverse event
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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:1
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作者 Ding Wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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Mechanical upper bowel obstruction caused by a large trichobezoar in a young woman: A very unusual case report 被引量:1
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作者 Magdalena Scherrer Peter Kornprat +2 位作者 Robert Sucher Johanna Muehlsteiner Doris Wagner 《World Journal of Clinical Cases》 SCIE 2024年第4期777-781,共5页
BACKGROUND Bezoars usually compile human fibers and debris.A special form of bezoar in case of psychologically altered individuals is the trichobezoar.It consists of voluntarily swallowed hair bulks and is normally re... BACKGROUND Bezoars usually compile human fibers and debris.A special form of bezoar in case of psychologically altered individuals is the trichobezoar.It consists of voluntarily swallowed hair bulks and is normally removed via gastroscopy.Trichobezoars leading to ileus have rarely been reported.CASE SUMMARY A 24-year-old female patient presented to the emergency room with abdominal pain,nausea,and vomiting for 3 d.Her previous medical and psychiatric history was unremarkable.Laboratory analysis showed iron deficiency anemia,leukocytosis,and elevated liver enzymes.An abdominal CT scan revealed a dense structure in the patients’stomach which turned out to be a huge trichobezoar completely obstructing the pylorus.The trichobezoar had to be removed surgi-cally.During her postoperative course,a subcutaneous seroma formed.After a single puncture,the rest of the recovery process was unremarkable,and the patient recovered fully.CONCLUSION A mechanical bowel obstruction is a potentially life-threatening event for every patient.In our case a young female was suffering from severe symptoms of an obstruction which might have resulted in serious harm without successful surgical management. 展开更多
关键词 Rapunzel syndrome Hair ingestion GASTROSCOPY BEZOAR case report
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Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report 被引量:1
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作者 Jiao Yang Xin-Ling Li Qing-Bing Li 《World Journal of Clinical Cases》 SCIE 2024年第5期1010-1017,共8页
BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultraso... BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultrasound-guided Lateral recess block(LRB)are limited,this is probably because there is no recognized standard method for ultrasound scanning.This study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis(LRS).CASE SUMMARY A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower limb.Physical examination showed ten-derness on the spinous process and paraspinal muscles from L1 to S1,extensor hallucis longus and tibialis anterior weakness(muscle strength:4-),and a positive straight leg raising test in the left lower limb(60°).Magnetic resonance imaging showed L4–L5 disc degeneration with left LRS and nerve root entrapment.Subsequently,the patient was diagnosed with LRS.This patient was treated with a novel ultrasound-guided LRB approach.The patient’s symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month follow-up.CONCLUSION This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane technique.Further studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS. 展开更多
关键词 Lateral recess stenosis ULTRASOUND Lateral recess block Real-time visualization Low back pain case report
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Communication Resource-Efficient Vehicle Platooning Control With Various Spacing Policies 被引量:2
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作者 Xiaohua Ge Qing-Long Han +1 位作者 Xian-Ming Zhang Derui Ding 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期362-376,共15页
Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical cha... Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical challenge in accomplishing automated vehicle platoons is to deal with the effects of intermittent and sporadic vehicle-to-vehicle data transmissions caused by limited wireless communication resources. This paper addresses the co-design problem of dynamic event-triggered communication scheduling and cooperative adaptive cruise control for a convoy of automated vehicles with diverse spacing policies. The central aim is to achieve automated vehicle platooning under various gap references with desired platoon stability and spacing performance requirements, while simultaneously improving communication efficiency. Toward this aim, a dynamic event-triggered scheduling mechanism is developed such that the intervehicle data transmissions are scheduled dynamically and efficiently over time. Then, a tractable co-design criterion on the existence of both the admissible event-driven cooperative adaptive cruise control law and the desired scheduling mechanism is derived. Finally, comparative simulation results are presented to substantiate the effectiveness and merits of the obtained results. 展开更多
关键词 Automated vehicles constant time headway spacing constant spacing cooperative adaptive cruise control event-triggered communication vehicle platooning
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Hybrid treatment of varied orthodontic appliances for a patient with skeletal class II and temporomandibular joint disorders:A case report and review of literature 被引量:1
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作者 Tong Lu Li Mei +2 位作者 Bao-Chao Li Zi-Wei Huang Huang Li 《World Journal of Clinical Cases》 SCIE 2024年第2期431-442,共12页
BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during or... BACKGROUND The relation between orthodontic treatment and temporomandibular disorders(TMDs)is under debate;the management of TMD during orthodontic treatment has always been a challenge.If TMD symptoms occur during orthodontic treatment,an immediate pause of orthodontic adjustments is recommended;the treatment can resume when the symptoms are managed and stabilized.CASE SUMMARY This case report presents a patient(26-year-old,female)with angle class I,skeletal class II and TMDs.The treatment was a hybrid of clear aligners,fixed appliances and temporary anchorage devices(TADs).After 3 mo resting and treatment on her TMD,the patient’s TMD symptom alleviated,but her anterior occlusion displayed deep overbite.Therefore,the fixed appliances with TAD were used to correct the anterior deep-bite and level maxillary and mandibular deep curves.After the levelling,the patient showed dual bite with centric relation and maximum intercuspation discrepancy on her occlusion.After careful examination of temporomandibular joints(TMJ)position,the stable bite splint and Invisible Mandibular Advancement appliance were used to reconstruct her occlusion.Eventually,the improved facial appearance and relatively stable occlusion were achieved.The 1-year follow-up records showed there was no obvious change in TMJ morphology,and her occlusion was stable.CONCLUSION TMD screening and monitoring is of great clinical importance in the TMD susceptible patients.Hybrid treatment with clear aligners and fixed appliances and TADs is an effective treatment modality for the complex cases. 展开更多
关键词 Temporomandibular disorder Skeletal class II Deep overbite Dual bite Invisible mandibular advancement appliance case report
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Distribution Characteristics and Controlling Factors of Heavy Metals in Surface Sediments from the Bay-Island-Estuary System(BIES):A Case Study in Coastal Waters of Fujian Province,China
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作者 LIU Bo HU Rijun +4 位作者 WANG Yonghong LI Yi ZHU Longhai ZHANG Xiaodong YUAN Xiaodong 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1253-1268,共16页
Based on the contents of six heavy metal elements in surface sediments from coastal areas of Fujian Province,the distribution characteristics and controlling factors of six heavy metals in a bay-island-estuary system(... Based on the contents of six heavy metal elements in surface sediments from coastal areas of Fujian Province,the distribution characteristics and controlling factors of six heavy metals in a bay-island-estuary system(BIES)were studied.This paper focuses on the influence of the hydrodynamic environment,and systematically discusses how grain size compositions,chemical environment,tidal current,ocean circulation and human activities influence the distribution and transportation of the heavy metals.The results indicated that the distribution and migration of Cu,Pb,Zn and Cr elements were mainly controlled by natural factors such as regional geological background,grain size compositions,and tidal residual currents.In contrast,As and Hg was mainly affected by human factors such as agriculture and industrial manufacturing.In the BIES,where the chemical environment exerted limited influence,the accumulation and migration of heavy metals are mainly influenced by human activities and enhanced by estuary processes as well as the complex sedimentary dynamic environment caused by many bays and islands. 展开更多
关键词 heavy metals sediments source to sink controlling factors hydrodynamic environment
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Robust Stability Analysis of Smith Predictor Based Interval Fractional-Order Control Systems:A Case Study in Level Control Process
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作者 Majid Ghorbani Mahsan Tavakoli-Kakhki +1 位作者 Aleksei Tepljakov Eduard Petlenkov 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第3期762-780,共19页
The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this work.Interval uncertaint... The robust stability study of the classic Smith predictor-based control system for uncertain fractional-order plants with interval time delays and interval coefficients is the emphasis of this work.Interval uncertainties are a type of parametric uncertainties that cannot be avoided when modeling real-world plants.Also,in the considered Smith predictor control structure it is supposed that the controller is a fractional-order proportional integral derivative(FOPID)controller.To the best of the authors'knowledge,no method has been developed until now to analyze the robust stability of a Smith predictor based fractional-order control system in the presence of the simultaneous uncertainties in gain,time-constants,and time delay.The three primary contributions of this study are as follows:ⅰ)a set of necessary and sufficient conditions is constructed using a graphical method to examine the robust stability of a Smith predictor-based fractionalorder control system—the proposed method explicitly determines whether or not the FOPID controller can robustly stabilize the Smith predictor-based fractional-order control system;ⅱ)an auxiliary function as a robust stability testing function is presented to reduce the computational complexity of the robust stability analysis;andⅲ)two auxiliary functions are proposed to achieve the control requirements on the disturbance rejection and the noise reduction.Finally,four numerical examples and an experimental verification are presented in this study to demonstrate the efficacy and significance of the suggested technique. 展开更多
关键词 Interval uncertainty FOPID controller fractional-order systems robust stability analysis smith predictor
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Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage 被引量:1
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作者 Jiatong Zhang Qi Zhu +4 位作者 Jie Wang Zheng Peng Zong Zhuang Chunhua Hang Wei Li 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期825-832,共8页
The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct facto... The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood flow.Mitochondria are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial dysfunction.Dysfunctional mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging cells.In response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological conditions.Specific interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid hemorrhage.This review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control mechanisms.It also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage. 展开更多
关键词 mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction mitochondrial fission and fusion mitochondrial quality control MITOPHAGY subarachnoid hemorrhage
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High-grade pancreatic intraepithelial neoplasia diagnosed based on changes in magnetic resonance cholangiopancreatography findings:A case report 被引量:1
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作者 Nao Furuya Atsushi Yamaguchi +13 位作者 Naohiro Kato Syuhei Sugata Takuro Hamada Takeshi Mizumoto Yuzuru Tamaru Ryusaku Kusunoki Toshio Kuwai Hirotaka Kouno Kazuya Kuraoka Yoshiyuki Shibata Sho Tazuma Takeshi Sudo Hiroshi Kohno Shiro Oka 《World Journal of Clinical Cases》 SCIE 2024年第8期1487-1496,共10页
BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most ... BACKGROUND High-grade pancreatic intraepithelial neoplasia(PanIN)exhibits no mass and is not detected by any examination modalities.However,it can be diagnosed by pancreatic juice cytology from indirect findings.Most previous cases were diagnosed based on findings of a focal stricture of the main pancreatic duct(MPD)and caudal MPD dilatation and subsequent pancreatic juice cytology using endoscopic retrograde cholangiopancreatography(ERCP).We experienced a case of high-grade PanIN with an unclear MPD over a 20-mm range,but without caudal MPD dilatation on magnetic resonance cholangiopancreatography(MRCP).CASE SUMMARY A 60-year-old female patient underwent computed tomography for a follow-up of uterine cancer post-excision,which revealed pancreatic cysts.MRCP revealed an unclear MPD of the pancreatic body at a 20-mm length without caudal MPD dilatation.Thus,course observation was performed.After 24 mo,MRCP revealed an increased caudal MPD caliber and a larger pancreatic cyst.We performed ERCP and detected atypical cells suspected of adenocarcinoma by serial pancreatic juice aspiration cytology examination.We performed a distal pancreatectomy and obtained a histopathological diagnosis of high-grade PanIN.Pancreatic parenchyma invasion was not observed,and curative resection was achieved.CONCLUSION High-grade Pan-IN may cause MPD narrowing in a long range without caudal MPD dilatation. 展开更多
关键词 Pancreatic cancer Pancreatic intraepithelial neoplasm High-grade pancreatic intraepithelial neoplasm Magnetic resonance cholangiopancreatography Carcinoma in situ case report
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Factors Controlling Organic Matter Enrichment in Alkaline Lacustrine Source Rocks:A Case Study of the Late Paleozoic Fengcheng Formation in the Junggar Basin,NW China
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作者 HUANG Renda JIANG Fujie +7 位作者 HU Tao CHEN Di HUANG Liliang LIU Zheyu WANG Xiaohao ZHANG Chenxi LU Jiahao WU Yuping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第6期1744-1755,共12页
The late Paleozoic Fengcheng Formation shale(LPF shale)in the Junggar Basin,NW China,is the oldest alkaline source rock discovered in the world,providing a unique perspective with which to explore organic matter(OM)en... The late Paleozoic Fengcheng Formation shale(LPF shale)in the Junggar Basin,NW China,is the oldest alkaline source rock discovered in the world,providing a unique perspective with which to explore organic matter(OM)enrichment in alkaline lake environments.Combined with the organic carbon isotope profile and paleoenvironmental proxies,this study reveals that the LPF shale was deposited in an arid climate with high salinity and a strong reducing environment,accompanied by frequent volcanic activity.High TOC values are concentrated in two intervals with frequent fluctuations in OM types.A negative excursion due to changes in sedimentary OM source is found in the δ^(13)C_(org) profile.The excursion corresponds to the OM enrichment interval and is accompanied by abnormally high values of Sr/Ba and Sr/Cu.This implies that the extreme arid climate has led to high salinity,resulting in strong reducibility and changes in paleontological assemblages,which in turn controlled the differential enrichment of OM.The Fengcheng Fm.high-quality source rocks are the result of the combined action of climatic events,volcanism,high-salinity water environment and superior hydrocarbon-generating organisms.The results provide new insights into the formation conditions of terrestrial alkaline high-quality source rocks and the factors controlling alkaline OM enrichment. 展开更多
关键词 organic matter enrichment control factors alkaline lake source rocks Fengcheng Formation Junggar Basin
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A Tutorial on Quantized Feedback Control
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作者 Minyue Fu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期5-17,共13页
In this tutorial paper, we explore the field of quantized feedback control, which has gained significant attention due to the growing prevalence of networked control systems. These systems require the transmission of ... In this tutorial paper, we explore the field of quantized feedback control, which has gained significant attention due to the growing prevalence of networked control systems. These systems require the transmission of feedback information, such as measurements and control signals, over digital networks, presenting novel challenges in estimation and control design. Our examination encompasses various topics, including the minimal information needed for effective feedback control, the design of quantizers, strategies for quantized control design and estimation,achieving consensus control with quantized data, and the pursuit of high-precision tracking using quantized measurements. 展开更多
关键词 Consensus control high-precision control networked control quantized estimation quantized feedback control robust control
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Development,sand control mechanism and hydrocarbon accumulation of beach-bar sandstone in a saline lake basin:A case from the Neogene of southwestern Qaidam Basin,NW China
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作者 WANG Yanqing LIU Zhanguo +8 位作者 SONG Guangyong ZHU Chao LI Senming WU Yanxiong XIA Zhiyuan SHI Qi JIA Shenglong WANG Zhaobing WEI Xuebin 《Petroleum Exploration and Development》 SCIE 2023年第4期851-864,共14页
Based on the data of field outcrops,drilling cores,casting thin sections,well logging interpretation,oil/gas shows during drilling,and oil/gas testing results,and combined with modern salt-lake sediments in the Qingha... Based on the data of field outcrops,drilling cores,casting thin sections,well logging interpretation,oil/gas shows during drilling,and oil/gas testing results,and combined with modern salt-lake sediments in the Qinghai Lake,the Neogene saline lake beach-bars in southwestern Qaidam Basin are studied from the perspective of sedimentary characteristics,development patterns,sand control factors,and hydrocarbon accumulation characteristics.Beach-bar sand bodies are widely developed in the Neogene saline lake basin,and they are lithologically fine sandstone and siltstone,with wavy bedding,low-angle cross bedding,and lenticular-vein bedding.In view of spatial-temporal distribution,the beach-bar sand bodies are stacked in multiple stages vertically,migratory laterally,and extensive and continuous in NW-SE trending pattern in the plane.The stacking area of the Neogene beach-bar sandstone is predicted to be 3000 km^(2).The water salinity affects the sedimentation rate and offshore distance of beach-bar sandstone,and the debris input from the source area affects the scale and enrichment of beach-bar sandstone.The ancient landform controls the morphology and stacking style of beach-bar sandstone,and the northwest monsoon driving effect controls the long-axis extension direction of beach-bar sandstone.The beach-bars have a reservoir-forming feature of“one reservoir in one sand body”,with thick beach-bar sand bodies controlling the effective reservoir distribution and oil-source faults controlling the oil/gas migration and accumulation direction.Three favorable exploration target zones in Zhahaquan,Yingdong-eastern Wunan and Huatugou areas are proposed based on the analysis of reservoir-forming elements. 展开更多
关键词 Qaidam Basin NEOGENE saline lake basin sedimentary characteristics beach-bar sand control mechanism reservoir characteristics
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Regional anesthesia in a patient with primary ciliary dyskinesia:A case report
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作者 Hyung Joon Park Ye Hwan Kim +1 位作者 Young Joon Yoon Sang Yun Cho 《World Journal of Clinical Cases》 SCIE 2024年第17期3183-3187,共5页
BACKGROUND Primary ciliary dyskinesia(PCD)is an inherited autosomal-recessive disorder of impaired mucociliary clearance characterized by chronic respiratory diseases,otolaryngological diseases,central nervous system ... BACKGROUND Primary ciliary dyskinesia(PCD)is an inherited autosomal-recessive disorder of impaired mucociliary clearance characterized by chronic respiratory diseases,otolaryngological diseases,central nervous system abnormalities,reproductive system abnormalities,and cardiac function abnormalities.General anesthesia in these patients is associated with a higher incidence of respiratory complications than in patients without the disease.CASE SUMMARY A 16-year-old male patient was referred to the emergency room complaining of right ankle pain due to distal tibiofibular fracture.Three years prior,he had been diagnosed with PCD.At that time,he had experienced several episodes of pneumonia,sinusitis,and chronic middle ear infections,for which he underwent surgical interventions.At the current admission,he presented with cough and sputum but no other respiratory symptoms.A chest computed tomography scan revealed centrilobular ground-glass opacities in both lower lobes and a calcified nodule in the left lower lobe.For the surgical procedure and postoperative pain management,combined spinal-epidural anesthesia was employed.The patient’s postoperative pain score was measured by the numerical rating scale(NRS).On the day of surgery,his NRS was 5 points.By the second postoperative day,the NRS score had decreased to 2–3 points.The epidural catheter was removed on the fourth day following the operation.The patient was subsequently discharged no respiratory complications.CONCLUSION We performed combined spinal-epidural anesthesia in a patient with PCD.The patient experienced no additional respiratory complications and was discharged with a low NRS score for pain. 展开更多
关键词 Primary ciliary dyskinesia Combined spinal-epidural anesthesia Patient controlled epidural analgesia Lower limb operation case report
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Finite-time Prescribed Performance Time-Varying Formation Control for Second-Order Multi-Agent Systems With Non-Strict Feedback Based on a Neural Network Observer
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作者 Chi Ma Dianbiao Dong 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期1039-1050,共12页
This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eli... This paper studies the problem of time-varying formation control with finite-time prescribed performance for nonstrict feedback second-order multi-agent systems with unmeasured states and unknown nonlinearities.To eliminate nonlinearities,neural networks are applied to approximate the inherent dynamics of the system.In addition,due to the limitations of the actual working conditions,each follower agent can only obtain the locally measurable partial state information of the leader agent.To address this problem,a neural network state observer based on the leader state information is designed.Then,a finite-time prescribed performance adaptive output feedback control strategy is proposed by restricting the sliding mode surface to a prescribed region,which ensures that the closed-loop system has practical finite-time stability and that formation errors of the multi-agent systems converge to the prescribed performance bound in finite time.Finally,a numerical simulation is provided to demonstrate the practicality and effectiveness of the developed algorithm. 展开更多
关键词 Finite-time control multi-agent systems neural network prescribed performance control time-varying formation control
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Quantization and Event-Triggered Policy Design for Encrypted Networked Control
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作者 Yongxia Shi Ehsan Nekouei 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第4期946-955,共10页
This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-trigger... This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-triggered strategy.Due to the fact that only integers can work in the Pailler cryptosystem,both the real-valued control gain and system state need to be first quantized before encryption.This is dramatically different from the existing quantized control methods,where only the quantization of a single value,e.g.,the control input or the system state,is considered.To handle this issue,static and dynamic quantization policies are presented,which achieve the desired integer conversions and guarantee asymptotic convergence of the quantized system state to the equilibrium.Then,the quantized system state is encrypted and sent to the controller when the triggering condition,specified by a state-based event-triggered strategy,is satisfied.By doing so,not only the security and confidentiality of data transmitted over the communication network are protected,but also the ciphertext expansion phenomenon can be relieved.Additionally,by tactfully designing the quantization sensitivities and triggering error,the proposed event-driven encrypted control framework ensures the asymptotic stability of the overall closedloop system.Finally,a simulation example of the secure motion control for an inverted pendulum cart system is presented to evaluate the effectiveness of the theoretical results. 展开更多
关键词 Cyber-security encrypted control event-triggered control(ETC) networked control systems(NCSs) semi-homomorphic encryption
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Practical Prescribed Time Tracking Control With Bounded Time-Varying Gain Under Non-Vanishing Uncertainties
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作者 Dahui Luo Yujuan Wang Yongduan Song 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期219-230,共12页
This paper investigates the prescribed-time control(PTC) problem for a class of strict-feedback systems subject to non-vanishing uncertainties. The coexistence of mismatched uncertainties and non-vanishing disturbance... This paper investigates the prescribed-time control(PTC) problem for a class of strict-feedback systems subject to non-vanishing uncertainties. The coexistence of mismatched uncertainties and non-vanishing disturbances makes PTC synthesis nontrivial. In this work, a control method that does not involve infinite time-varying gain is proposed, leading to a practical and global prescribed time tracking control solution for the strict-feedback systems, in spite of both the mismatched and nonvanishing uncertainties. Different from methods based on control switching to avoid the issue of infinite control gain that involves control discontinuity at the switching point, in our method a softening unit is exclusively included to ensure the continuity of the control action. Furthermore, in contrast to most existing prescribed-time control works where the control scheme is only valid on a finite time interval, in this work, the proposed control scheme is valid on the entire time interval. In addition, the prior information on the upper or lower bound of gi is not in need,enlarging the applicability of the proposed method. Both the theoretical analysis and numerical simulation confirm the effectiveness of the proposed control algorithm. 展开更多
关键词 Adaptive control prescribed time control(PTC) strict-feedback systems tracking control
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