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The Short Local Algebras of Dimension 6 with Non-projective Reflexive Modules

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Communications in Mathematics and Statistics 2023年第2期11卷 195-227页

作者： claus michael Ringel Fakultät für Mathematik Universität BielefeldPO Box 10013133501 BielefeldGermany

Let A be a finite-dimensional local algebra over an algebraically closed field,let J be the radical of *** modules we are interested in are the finitely generated left *** are always reflexive,and an algebra is self-injective iff allmodules are *** discuss the existence of non-projective reflexive modules in case A is not *** assume that A is short(this means that J^(3)=0).In a joint paper with Zhang Pu,it has been shown that 6 is the smallest possible dimension of A that can occur and that in this case the following conditions have to be satisfied:J^(2)is both the left socle and the right socle of A and there is no uniform ideal of length *** present paper is devoted to showing the converse.

关键词： Short local algebra Reflexive module Gorenstein-projective module Bristle Atom Bar Bristle-bar layout

Representation theory of Dynkin quivers. Three contributions

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Frontiers of Mathematics in China 2016年第4期11卷 765-814页

作者： claus michael RINGEL Fakultat fiir Mathematik Universitat Bielefeld P. O. Box 100 131 D-33501 Bielefeld Germany Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China

The representations of the Dynkin quivers and the corresponding Euclidean quivers are treated in many books. These notes provide three building blocks for dealing with representations of Dynkin （and Euclidean） quivers. They should be helpful as part of a direct approach to study representations of quivers, and they shed some new light on properties of Dynkin and Euclidean quivers.

关键词： Quiver Dynkin quiver Euclidean quiver the exceptional vertices of a Dynkin quiver representations of quivers thin representations filtrations of vector spaces conical representations of star quivers Auslander- Reiten quiver thick subcategories perpendicular subcategories one-point extension antichains of a poset antichains of an additive category simplifi- cation hammocks the 2-4-8 property the magic Freudenthal-Tits square

Objective triangle functors

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Science China Mathematics 2015年第2期58卷 221-232页

作者： RINGEL claus michael ZHANG Pu Department of Mathematics Shanghai Jiao Tong University Department of Mathematics King Abdulaziz University

An additive functor F:A→B between additive categories is said to be objective,provided any morphism f in A with F(f)=0 factors through an object K with F(K)=*** concentrate on triangle functors between triangulated *** first aim of this paper is to characterize objective triangle functors F in several ***,we are interested in the corresponding Verdier quotient functors VF:A→A/Ker F,in particular we want to know under what conditions VF is *** third question to be considered concerns the possibility to factorize a given triangle functor F=F2F1with F1a full and dense triangle functor and F2a faithful triangle *** turns out that the behavior of splitting monomorphisms and splitting epimorphisms plays a decisive role.

关键词： triangulated category triangle functor objective functor Verdier functor

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根偏序集及其富反链

中国科学：数学 2018年第11期48卷 1483-1506页

作者： claus michael Ringel Fakultat für Mathematik Universitat Bielefeld 33501Germany

令?为一个秩为n(n≥2)的(连通)Dynkin图(diagram),令Φ_+=Φ_+(?)为对应的根偏序集(root poset)(它由对应于一个固定的根基(root basis)的所有正根构成).Φ_+的宽度(width)是n.本文将证明Φ_+是"圆锥形的"(conical),即它是n个实心链(solid chain)的非交并.Φ_+中的富反链(rich antichain)是基数(cardinality)为n-1的反链.众所周知,富反链的个数等于Φ_+的基数.Φ_+中富反链的集合R(?)自身可看作是一个偏序集,它与Φ_+相似,却并不总是同构于Φ_+.本文将证明,总是存在唯一的富反链A使得任意富反链都包含在由A生成的理想中.对于?≠E_6,A中所有根的长度都相同,即为e_2,其中e_1≤e_2≤···≤e_n是?的指数(exponent).对于?=E_6,反链A包含四个长度为e_2=4的根和一个长度为5的根.

关键词：根根偏序集反链富反链

Sclerotherapy as a primary or salvage procedure for aneurysmal bone cysts:A single-center experience

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World Journal of Orthopedics 2023年第9期14卷 698-706页

作者： Kolja Sebastian Weber claus Lindkær Jensen michael Mørk Petersen Department of Orthopedic Surgery RigshospitaletCopenhagen 2100Denmark

BACKGROUND Aneurysmal bone cysts(ABC)are benign cystic bone tumors of an osteolytic and locally aggressive *** an alternative to the primary treatment of choice,which consists of curettage with bone grafting,alternative treatment methods with promising results have been *** our department,we have,in recent years,used percutaneous sclerotherapy with *** objective of this study was to identify the healing rate and safety of sclerotherapy with *** To identify the efficacy and safety of sclerotherapy with polidocanol in primary and recurrent *** Twenty-two consecutive patients(median age 12.5 years;range 1-27)with 23 ABCs treated with sclerotherapy with polidocanol from 2016-2021 were included *** patients(48%)had undergone different forms of previous treatment with *** general anesthesia and fluoroscopic guidance,repeated percutaneous injections of 4mg polidocanol/kg body weight were *** review of the electronic medical records,the following were identified:healing and recurrence rate,number of treatments,gender,age,comorbidity,location of the tumor and side effects/complications,as well as any previous surgery for *** median length of radiographic follow-up was 19.5 *** All ABCs except one(96%)showed healing or stable disease after a median of 4(range 1-8)*** clinical and radiographic healing was observed in 16 cysts(70%),while partial radiographic healing with resolution of pain was seen in 6 cases(26%)and considered as stable *** cyst that failed to heal had previously undergone curettage twice with *** patient with a large pelvic ABC experienced,right after two injections,a sudden drop in blood pressure,which could quickly be *** patient with a juxtaphyseal ABC in the femoral neck showed a minor limb length discrepancy because of *** that,no complications were *** Percutaneous sclerotherapy

关键词： Aneurysmal bone cyst Bone tumor Sclerotherapy Polidocanol Healing rate Complications

Progressive changes in platelet counts and Fib-4 scores precede the diagnosis of advanced fibrosis in NASH patients

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World Journal of Hepatology 2023年第2期15卷 225-236页

作者： michael K Zijlstra Anuhya Gampa Nora Joseph Amnon Sonnenberg claus J Fimmel Department of Internal Medicine NorthShore University Health SystemEvanstonIL 60201United States Division of Gastroenterology and Hepatology University of Chicago Pritzker School of MedicineChicagoIL 60637United States Department of Pathology NorthShore University Health SystemEvanstonIL 60201United States Portland VA Medical Center PortlandOR 97239United States Department of Gastroenterology Oregon Health Sciences UniversityPortlandOR 97201United States Division of Gastroenterology Department of Internal MedicineNorthShore University Health SystemEvanstonIL 60201United States

BACKGROUND Cirrhosis and its complications develop in a subgroup of patients with nonalcoholic fatty liver disease(NASH).Early detection of liver fibrosis represents an important goal of clinical *** To test the hypothesis that the development of cirrhosis in nonalcoholic fatty liver disease patients is preceded by the long-term trends of platelet counts and Fib-4 *** We identified all patients in our healthcare system who had undergone fibrosis staging by liver biopsy or magnetic resonance elastography(MRE)for nonalcoholic fatty liver disease during the past decade(n=310).Platelet counts,serum glutamic-pyruvic transaminase and serum glutamic oxalacetic transaminase values preceding the staging tests were extracted from the electronic medical record system,and Fib-4 scores were *** predictors of advanced fibrosis were evaluated using multivariate regression *** Significant decreases in platelet counts and increases in Fib-4 scores were observed in all fibrosis stages,particularly in patients with *** the liver biopsy group,the presence of cirrhosis was best predicted by the combination of the Fib-4 score at the time closest to staging(P<0.0001),the presence of diabetes(P=0.0001),and the correlation coefficient of the preceding timedependent drop in platelet count(P=0.044).In the MRE group,Fib4 score(P=0.0025)and platelet drop(P=0.0373)were significant *** comparison,the time-dependent rise of the Fib-4 score did not contribute in a statistically significant *** Time-dependent changes in platelet counts and Fib-4 scores contribute to the prediction of cirrhosis in NASH patients with biopsy-or MRE-staged *** incorporation into predictive algorithms may assist in the earlier identification of high-risk patients.

关键词： Non-alcoholic fatty liver disease Liver fibrosis cirrhosis Prediction Liver biopsy Magnetic resonance elastography

Impact of genetic variation of tumor necrosis factor-α on gestational hypertension

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Chinese Medical Journal 2006年第9期119卷 719-724页

作者： CHEN You-peng Thiemo Pfab Torsten Slowinski claus-michael Richter michael Godes Berthold Hocher Division of Infectious Disease Department of Interal Medicine First Affiliated Hospital of Jinan University Jinan University Guangzhou 510632 China Center for Cardiovascular Research Medical School Charit6 Humboldt University of Berlin Berlin D-10115 Germany Institute of Pharmacology and Toxicology Medical School Charitd Humboldt University of Berlin Berlin D-10115 Germany

Background The mechanisms responsible for the pathogeneses of gestational hypertension and preeclampsia are unclear. Tumor necrosis factor-1α （TNF-1α） is a pro-inflammatory Th1-type cytokine. TNFA gene is located in the human leukocyte antigen （HLA） class Ⅲ region of the major histocompatibility complex （MHC） on chromosome 6. The high TNF-1α mRNA expression may be associated with the TNF2 （A） allele, which is the polymorphism of TNF-1α at position - 308 in promoter region. This study assessed whether the TNF2 （A） allele at position -308 plays a role in the alteration of blood pressure （BP） and urinary protein excretion during pregnancy. Methods The original prospective cohort study comprised 1623 pregnant women from January 2000 to October 2001. The G/A polymorphism was done by restriction fragment length polymorphism （RFLP） analysis with Nco I enzyme. Results The distributions of the G/A polymorphism of TNF-1α in the promoter region at position -308 were wild-type 72.4% and variant 27.6%, respectively. The frequency of TNF2 （A） allele was approximately 0.15 for Caucasian pregnant women in the study. It was not significantly different in the distributions of genotypes and G/A allele frequencies among the three groups of pregnant women with gestational hypertension, preexisting hypertension and normal blood pressure （P〉0.05）. The maternal blood pressure in the third trimester was significantly higher in the group of women possessing the TNF2 （A） allele compared to homozygous for the TNF1 （G） allele （systolic BE P〈0.01 and diastolic BE P〈0.05）. The elevated blood pressure in the TNF2 （A） group was accompanied by higher urinary protein excretion in the third trimester （P〈0.05）. The blood pressure and urinary protein excretion did not change apparently between the two groups in the first and second trimesters （P〉0.05）. Conclusions Maternal TNF2 （A） allele of TNF-1α promoter region at position -308 could play a role in the alteration of blood pressures and/or enhan

关键词： tumor necrosis factor-α polymorphism, restriction fragment length gestational hypertension

Clinical outcome after surgery on schwannomas in the extremities

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World Journal of Orthopedics 2021年第10期12卷 760-767页

作者： Andreas Saine Granlund Michala Skovlund Sørensen claus Lindkær Jensen Birthe Højlund Bech michael Mørk Petersen Musculoskeletal Tumor Section Department of Orthopedic SurgeryCopenhagen University HospitalRigshospitaletCopenhagen 2100Denmark Department of Orthopedic Surgery Copenhagen University HospitalCopenhagen 2200Denmark Musculoskeletal Tumor Section Department of Orthopedic SurgeryUniversity of CopenhagenCopenhagen 2100Denmark Department of Radiology RigshospitaletUniversity of CopenhagenCopenhagen 2100Denmark

BACKGROUND Schwannoma is a benign,encapsulated and slowly growing tumor originating from Schwann cells and is rarely seen in the peripheral nerve *** symptoms are soreness,radiating pain and sensory loss combined with a soft tissue *** To evaluate pre-and postoperative symptoms in patients operated for schwannomas in the extremities and investigate the rate of malignant *** In this single center retrospective study design,all patients who had surgery for a benign schwannoma in the extremities from May 1997 to January 2018 were *** location of the tumor in the extremities was divided into five groups;forearm,arm,shoulder,thigh and leg including *** locations of the tumor in the nerves were also categorized as either;proximal,distal,minor or major *** the pre-and postoperative clinical evaluation,symptoms were classified as paresthesia,local pain,radiating pain,swelling,impairment of mobility/strength and asymptomatic tumors that were found incidentally(with magnetic resonance imaging).The patients were evaluated after surgery using the following categories:Asymptomatic or symptomatic patients(radiating and/or local pain)and those with *** follow up period was from the time of surgery until last examination of the particular *** logistic regression analysis was performed to identify independent prognostic factors for postoperative significant symptoms at *** We identified 858 cases from the institutional pathology *** excluded cases with duplicate diagnoses(n=407),pathology not including schwannomas(n=157),lesions involving the torso,spine and neck(n=150)leaving 144 patients for further *** this group 99 patients underwent surgery and there were five complications recorded:2 infections(treated with antibiotics)and 3 nerve palsies(2 involving the radial nerve and one involving the median nerve)that recovered *** the end of follow-up,1.4

关键词： Schwannoma Extremities Surgery Removal Symptoms Outcome

The clinical impact of bacterial biofilms

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International Journal of Oral Science 2011年第2期3卷 55-65页

作者： Niels Hoiby Oana Ciofu Helle Krogh Johansen Zhi-jun Song claus Moser Peter Ostrup Jenser Soren Molin michael Givskov Tim Tolker-Nieisen Thomas Bjamsholt Department of Clinical Microbiology Rigshospitalet Institute for International Health Medical Microbiology and Immunology BloScience and Technology Biocentrum Danish Technical University

Bacteria survive in nature by forming biofilms on surfaces and probably most, if not all, bacteria （and fungi） are capable of forming biofilms. A biofilm is a structured consortium of bacteria embedded in a self-produced polymer matrix consisting of polysaccharide, protein and extracellular DNA. Bacterial biofilms are resistant to antibiotics, disinfectant chemicals and to phagocytosis and other components of the innate and adaptive inflammatory defense system of the body. It is known, for example, that persistence of staphylococcal infections related to foreign bodies is due to biofilm formation. Likewise, chronic Pseudomonas aeruginosa lung infections in cystic fibrosis patients are caused by biofilm growing mucoid strains. Gradients of nutrients and oxygen exist from the top to the bottom of biofilms and the bacterial cells located in nutrient poor areas have decreased metabolic activity and increased doubling times. These more or less dormant cells are therefore responsible for some of the tolerance to antibiotics. Biofilm growth is associated with an increased level of mutations. Bacteria in biofilms communicate by means of molecules, which activates certain genes responsible for production of virulence factors and, to some extent, biofilm structure. This phenomenon is called quorum sensing and depends upon the concentration of the quorum sensing molecules in a certain niche, which depends on the number of the bacteria. Biofilms can be prevented by antibiotic prophylaxis or early aggressive antibiotic therapy and they can be treated by chronic suppressive antibiotic therapy. Promising strategies may include the use of compounds which can dissolve the biofilm matrix and quorum sensing inhibitors, which increases biofilm susceptibility to antibiotics and phagocytosis.

关键词： bacterial biofilm biofilm infection antibiotic resistance quorum sensing