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Fluorescent carbon dots synthesized in solid phase and air for application in LEDs

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Nano Research 2024年第9期17卷 8495-8503页

作者： Wei-Jie zheng Zhao-Nan Sun yi-Ming Wang Huan-Ming xiong Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan UniversityShanghai 200438China

Carbon dots(CDs)have been widely adopted as optical materials because of their excellent luminescent ***,most of the reported synthetic methods are conducted in solvents,especially hydrothermal/solvothermal reactions,leading to intractable problems such as toxic and flammable solvents,complex and inseparable by-products,and dangerously high pressures and ***-phase synthesis of CDs in air is an effective solution to overcome the above issues,but solid reactions always result in uncontrolled growth and agglomeration of *** this study,some inorganic salts are selected as catalysts for synthesizing CDs in solid states and air,which also play as dispersants to hinder CDs *** the meantime,some aromatic derivatives containing hydroxyl and amino groups are chosen as carbon sources,ground with the optimized catalyst,and then heated together in *** production yields are affected by the reaction time and reactant ratio,while the graphitization degrees of the CDs are determined by the reaction *** IG/ID value of their Raman spectra increases from 0.59 to 0.85,and the particle size decreases from 2.5 to 1.4 nm when the synthesis temperature is increased from 200 to 280℃.The as-prepared CDs show emission peaks ranging from 366 to 606 nm,with the photoluminescence(PL)quantum yield up to 53%.Their emission color variation mainly results from different carbon sources,which can be ascribed to the differences in the element composition,functional groups,and graphitic nitrogen content of these *** dispersing CDs of different concentrations into polyvinyl alcohol(PVA)and combining them with blue LEDs,cold,standard,and warm white light emitting devices(WLEDs)are prepared,with a color rendering index(CRI)up to *** the as-prepared CDs have antioxidant ability at high temperature,the as-prepared WLEDs have long lifespans,remaining the effective white luminescence after 72 h continuous work.

关键词： carbon dot solid-phase synthesis white LED photoluminescence inorganic salt catalysis

Systematic review of laparoscopy-assisted versus open gastrectomy for advanced gastric cancer

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第6期14卷 468-478页

作者： Long-yun YE Da-ren LIU Chao LI Xiao-wen LI Ling-na HUANG Sheng YE yi-xiong zheng Li CHEN Department of Surgery the Second Affiliated HospitalSchool of MedicineZhejiang University

Objective:The study compared laparoscopy-assisted gastrectomy(LAG) with open gastrectomy(OG) in the management of advanced gastric cancer(AGC).Methods:Literature search was performed in the Medline,Embase,and Cochrane Library databases to identify control studies that compared LAG and OG for AGC.A meta-analysis was conducted to examine the surgical safety and oncologic adequacy,using the random-effect ***:Seven eligible studies including 815 patients were *** was associated with less blood loss,less use of analgesics,shorter time of flatus and periods of hospital stay,but longer time of *** incidence of most complications was similar between the two ***,LAG was associated with a lower rate of pulmonary infection(odds ratio(OR) 0.19;95% confidence interval(CI) 0.05 to 0.68;P0.05),overall mortality(OR 0.65;95% CI 0.39 to 1.10;P>0.05),cancer-related mortality(OR 0.64;95% CI 0.32 to 1.25;P>0.05),or recurrence(OR 0.62;95% CI 0.33 to 1.16;P>0.05).Conclusions:LAG could be performed safely for AGC with adequate lymphadenectomy and has several short-term advantages compared with conventional *** differences were found in long-term ***,these results should be validated in large randomized controlled studies(RCTs) with sufficient follow-up.

关键词： Gastric cancer Laparoscopic gastrectomy Meta-analysis Mortality Recurrence

An Example of Embedded Singular Continuous Spectrum for Discrete Schrödinger Operators

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1837-1849页

作者： zheng Qi FU xiong LI Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875P.R.China

We present an example of a potential such that the corresponding discrete Schrödinger operator has singular continuous spectrum embedded in the absolutely continuous spectrum.

关键词： Sparse potentials singular continuous spectrum Prüfer variables

Convex-up Style of Deformation within Grabens in Regions of Incomplete Crossing Conjugate Normal Faults: A Numerical Simulation Investigation and Case Study

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Journal of Earth Science 2024年第3期35卷 839-849页

作者： zheng Li Kai Wang xiong xiong Bing Zhou School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China State Key Laboratory of Geodesy and Earth’s Dynamics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430077China Department of Earth Sicences Khalifa UniversityAbu DhabiUnited Arab Emirates

Crossing conjugate normal faults(CCNFs)are extensively developed in many hydrocarbon-producing basins,generally existing in the form of incomplete ***,the effect of the non-conjugate zone of the CCNFs on the conjugate relay zone post late tectonic action has not been previously *** use 3D elastic-plastic modeling to investigate the influence of incomplete(i.e.,partially intersecting)CCNFs on the pattern of deformation of strata in the intersection region.A series of model simulations were performed to examine the effects of horizontal tectonic extension,fault size,and fault depth on the deformation of conjugate relay zones of incomplete *** analyses yielded the following results.(1)The model of incomplete conjugation predicts a convex-up style of deformation in the conjugate graben region superimposed on overall subsidence under applied horizontal tectonic extension.(2)The degree of convex-up deformation of the conjugate graben depends on the influence of the non-conjugate zone on the conjugate relay zone,which varies with the amount of horizontal tectonic extension,fault size,and fault burial depth.(3)Our results indicate that incomplete CCNFs can form convex-up deformation,similar to that in the Nanpu Sag area and provide a sound understanding of hydrocarbon migration and accumulation.

关键词： incomplete conjugate normal fault conjugate graben convex-up deformation hydrocarbons Nanpu Sag tectonics.

The Logarithmic Sobolev Inequality for a Submanifold in Manifolds with Nonnegative Sectional Curvature

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 487-496页

作者： Chengyang yi Yu zheng School of Mathematical Sciences East China Normal UniversityShanghai 200241China

The authors prove a sharp logarithmic Sobolev inequality which holds for compact submanifolds without boundary in Riemannian manifolds with nonnegative sectional curvature of arbitrary dimension and *** the Michael-Simon Sobolev inequality,this inequality includes a term involving the mean *** extends a recent result of Brendle with Euclidean setting.

关键词： Logarithmic Sobolev inequality Nonnegative sectional curvature Submanifold

A Semiparametric Additive-multiplicative Rates Model for the Weighted Composite Endpoint of Recurrent and Terminal Events

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Acta Mathematica Sinica,English Series 2024年第4期40卷 985-999页

作者： yi DENG Qiang xiong Shu Wei LI School of Economics and Statistics Guangzhou UniversityGuangzhou 510006P.R.China

Recurrent event data are commonly encountered in many scientific fields,including biomedical studies,clinical trials and epidemiological surveys,and many statistical methods have been proposed for their *** this paper,we consider to use a weighted composite endpoint of recurrent and terminal events,which is weighted by the severity of each event,to assess the overall effects of covariates on the two types of events.A flexible additive-multiplicative model incorporating both multiplicative and additive effects on the rate function is proposed to analyze such weighted composite event process,and more importantly,the dependence structure among the recurrent and terminal events is left *** the estimation,we construct the unbiased estimating equations by virtue of the inverse probability weighting technique,and the resulting estimators are shown to be consistent and asymptotically normal under some mild regularity *** evaluate the finite-sample performance of the proposed method via simulation studies and apply the proposed method to a set of real data arising from a bladder cancer study.

关键词： Additive-multiplicative rates model estimating equation recurrent events terminal event weighted composite endpoint

Retrorectal mucinous adenocarcinoma arising from a tailgut cyst:A case report and review of literature

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World Journal of Gastrointestinal Surgery 2022年第9期14卷 1072-1081页

作者： Yan-Shuai Wang Qing-Yun Guo Fang-Hong zheng Zi-Wei Huang Jia-Lang Yan Fu-Xiang Fan Tian Liu Shun-Xian Ji Xiao-Feng Zhao yi-xiong zheng Department of General Surgery The Fourth Affiliated HospitalSchool of MedicineZhejiang UniversityYiwu 322000Zhejiang ProvinceChina Department of Gynecology Women's HospitalSchool of MedicineZhejiang UniversityHangzhou 310006Zhejiang ProvinceChina Department of Intensive Care Unit The Fourth Affiliated HospitalSchool of MedicineZhejiang UniversityYiwu 322000Zhejiang ProvinceChina Department of Pathology The Fourth Affiliated HospitalSchool of MedicineZhejiang UniversityYiwu 322000Zhejiang ProvinceChina

BACKGROUND Tailgut cysts are defined as congenital cysts that develop in the rectosacral space from the residue of the primitive *** a congenital disease,caudal cysts are very rare,and their canceration is even rarer,which makes the disease prone to misdiagnosis and delayed *** describe a case of caudal cyst with adenocarcinogenesis and summarize in detail the characteristics of cases with analytical value reported since *** SUMMARY A 35-year-old woman found a mass in her lower abdomen 2 mo *** was asymptomatic at that time and was not treated because of the coronavirus disease 2019 *** weeks ago,the patient developed abdominal distension and right waist discomfort and came to our *** for the high level of serum carcinoembryonic antigen,the medical history and laboratory tests were not *** resonance imaging showed a well-defined,slightly lobulated cystic-solid mass with a straight diameter of approximately 10 cm×9 cm in the presacral space,slightly high signal intensity on T2-weighted imaging,and moderate signal intensity on T1-weighted *** mass was completely removed by laparoscopic *** examination showed that the lesion was an intestinal mucinous adenocarcinoma,and the multidisciplinary team decided to implement postoperative *** patient recovered well,the tumor marker levels returned to normal,and tumor-free survival has been achieved thus *** The case and literature summary can help clinicians and researchers develop appropriate examination and therapeutic methods for diagnosis and treatment of this rare disease.

关键词： Tailgut cysts Adenocarcinoma Magnetic resonance imaging Retrorectal disease Preoperative biopsy Case report

Diagnosis and management of colonic injuries following blunt trauma

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World Journal of Gastroenterology 2007年第4期13卷 633-636页

作者： yi-xiong zheng Li Chen Si-Feng Tao Ping Song Shao-Ming Xu Department of Surgery Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 Zhejiang Province China

AIM: To retrospectively evaluate the preoperative diagnostic approaches and management of colonic injuries following blunt abdominal trauma. METHODS: A total of 82 patients with colonic injuries caused by blunt trauma between January 1992 and December 2005 were enrolled. Data were collected on clinical presentation, investigations, diagnostic methods, associated injuries, and operative management. Colonic injury-related mortality and abdominal complications were analyzed. RESULTS: Colonic injuries were caused mainly by motor vehicle accidents. Of the 82 patients, 58 (70.3%) had other associated injuries. Laparotomy was performed within 6 h after injury in 69 cases (84.1%), laparoscopy in 3 because of haemodynamic instability. The most commonly injured site was located in the transverse colon. The mean colon injury scale score was 2.8. The degree of faecal contamination was classified as mild in 18 (22.0%), moderate in 42 (51.2%), severe in 14 (17.1%), and unknown in 8 (9.8%) cases. Sixty-seven patients (81.7%) were treated with primary repair or resection and anastomosis. Faecal stream diversion was performed in 15 cases (18.3%). The overall mortality rate was 6.1%. The incidence of colonic injury- related abdominal complications was 20.7%. The only independent predictor of complications was the degree of peritoneal faecal contamination (P = 0.02). CONCLUSION: Colonic injuries following blunt trauma are especially important because of the severity and complexity of associated injuries. A thorough physical examination and a combination of tests can be used to evaluate the indications for laparotomy. One stage management at the time of initial exploration is mostoften used for colonic injuries.

关键词： Colonic injuries Blunt trauma Operation Faecal stream diversion Rretrospective study

A blockchain-empowered authentication scheme for worm detection in wireless sensor network

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Digital Communications and Networks 2024年第2期10卷 265-272页

作者： Yuling Chen xiong Yang Tao Li yi Ren Yangyang Long State Key Laboratory of Public Big Data College of Computer Science and TechnologyGuizhou UniversityGuiyang550025China School of Computing Science University of East AngliaNorwichNR57TJUK

Wireless Sensor Network(WSN)is a distributed sensor network composed a large number of nodes with low cost,low performance and *** special structure of WSN brings both convenience and *** example,a malicious participant can launch attacks by capturing a physical ***,node authentication that can resist malicious attacks is very important to network ***,blockchain technology has shown the potential to enhance the security of the Internet of Things(IoT).In this paper,we propose a Blockchain-empowered Authentication Scheme(BAS)for *** our scheme,all nodes are managed by utilizing the identity information stored on the ***,the simulation experiment about worm detection is executed on BAS,and the security is evaluated from detection and infection *** experiment results indicate that the proposed scheme can effectively inhibit the spread and infection of worms in the network.

关键词： Wireless Sensor Network(WSN) Node authentication Blockchain Tangle Worm detection