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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

Oncostatin M:a love-hate relationship in neuroinflammation

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Neural Regeneration Research 2024年第12期19卷 2571-2572页

作者： Doryssa Hermans niels Hellings Bieke Broux University MS Center Campus DiepenbeekDiepenbeekBelgium Neuro-Immune Connections and Repair Lab Department of Immunology and InfectionBiomedical Research InstituteHasselt UniversityDiepenbeekBelgium

Oncostatin M and multiple sclerosis:Every 5minutes,someone in the world is diagnosed with multiple sclerosis(MS),a chronic inflammatory and degenerative disease of the central nervous system(CNS).MS appears in unpredictable episodes of symptoms,which are highly patient-dependent,but often include visual impairment,muscle weakness/spasms,fatigue,cognitive difficulties,and *** sexual dysfunction.

关键词： visual bladder someone

卡介苗预先免疫对大鼠慢性绿脓杆菌性肺炎的影响

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现代免疫学 2004年第2期24卷 138-141页

作者：郭向华宋志军吴红闫萍覃雪君 Kalai Mathee niels hoiby 唐步坚仇晓强陈一强广西医科大学医学科学实验中心南宁530021 Department of Biological Sciences Florida International University Department of Clinical Microbiology University Hospital of Copenhagen

为了探讨卡介苗 (BCG )预先免疫对大鼠慢性绿脓杆菌 (PA )性肺炎模型的影响。采用BCG或灭菌生理盐水皮内注射预先免疫 3周 ,然后由支气管内予以PA攻击 ;2周后评估各组的肺部细菌学、肺组织病理学、肺部细胞因子 (IL 4、IFN γ、TNF α ... 详细信息

为了探讨卡介苗 (BCG )预先免疫对大鼠慢性绿脓杆菌 (PA )性肺炎模型的影响。采用BCG或灭菌生理盐水皮内注射预先免疫 3周 ,然后由支气管内予以PA攻击 ;2周后评估各组的肺部细菌学、肺组织病理学、肺部细胞因子 (IL 4、IFN γ、TNF α )反应、血清PA特异性抗体IgG水平的变化。结果显示BCG免疫组肺组织内的IFN γ、TNF α水平显著升高 (P 0 0 5 )。以上结果提示BCG接种能够诱导肺部Th1型免疫反应 ,加快PA性肺炎大鼠肺部的细菌清除。

关键词：卡介苗绿脓杆菌肺部感染囊性纤维化动物模型细胞因子医院感染免疫疗法

Semi-analytical calculation model for friction of polymers on the example of POM|PE-UHMW and steel|PE-UHMW

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Friction 2024年第10期12卷 2355-2369页

作者： André BERGMANN Jens SUMPF niels DALLINGER Martin MONEKE Markus GOLDER Professorship of Conveying Engineering and Materials Handling Chemnitz University of TechnologySachsen 09126Germany Institute of Plastics Engineering Darmstadt University of Applied SciencesDarmstadt 64295Germany

In this paper,a semi-analytical calculation model for the coefficient of friction(COF)of single spherical protrusions is *** allows the prediction of the deformative friction part(μ_(def))and adhesive friction part(μ_(def))of the friction pairings steel|polyethylene with ultra-high molecular weight(PE-UHMW)and polyoxymethylene(POM)|*** experimental studies included unlubricated friction tests,which served to determine the total COF(μ_(def)),as well as tests being lubricated with silicone oil,from whichμ_(def)is *** on the verification tests,it could be shown that both states of lubrication result in the same deformation and that the relationship between the rear angle(w)andμ_(def)postulated in the calculation model is ***,friction tests with segmented spheres were carried out,which allow a specific variation of *** can be concluded that for both pairings theμ_(def)is generally of minor significance(approx.1/3μ_(tot))and the influence of theμ_(adh)predominates(approx.2/3μ_(tot))the friction *** themtot decreases with increasing contact pressure especially in the low pressure range and depends on the form of motion(continuous and discontinuous).

关键词： tribology friction polymers model contact polyoxymethylene(POM) polyethylene with ultra-high molecular weight(PE-UHMW)

用于振动模态可操纵性的克拉尼图形拓扑优化设计

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Acta Mechanica Sinica 2024年第4期40卷 172-184页

作者：薛亮文桂林 Fengwen Wang niels LPedersen School of Mechanical Engineering Yanshan UniversityQinhuangdao066004China Department of Civil and Mechanical Engineering Solid MechanicsTechnical University of DenmarkKgs.Lyngby2800Denmark Body Hunan UniversityChangsha410082China

经典克拉尼图形(Chladni patterns,CP)是特征向量的视觉表示,在振动分析、乐器设计、粒子操纵和分离等领域中具有广泛的应用.均质结构通常会表现出高度规则化的CP,这限制它们的应用场景.因此,实现面向应用来逆向设计结构的CP是非常重要... 详细信息

经典克拉尼图形(Chladni patterns,CP)是特征向量的视觉表示,在振动分析、乐器设计、粒子操纵和分离等领域中具有广泛的应用.均质结构通常会表现出高度规则化的CP,这限制它们的应用场景.因此,实现面向应用来逆向设计结构的CP是非常重要的,而这可以通过使用拓扑优化来实现CP的逆向设计.本研究提出了一种使用基于密度的拓扑优化算法来设计结构CP的方法.优化列式中,给出了描述图形的指标函数,并以最小化特征向量和目标CP之间的误差构建了优化目标.数值结果表明,所提出的方法可以为指定的单阶或多阶CP生成新颖的材料分布.这表明了本文所提出的方法能够实现CP的精确定制设计,进一步为面向应用的需求提供了更多选择.

关键词：定制设计面向应用逆向设计指标函数特征向量拓扑优化可操纵性振动模态

Physiological and perceptual responses to sprint interval exercise using arm versus leg cycling ergometry

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Sports Medicine and Health Science 2024年第4期6卷 385-393页

作者： Todd A.Astorino Shealin Pierce Madisen B.Piva Richard S.Metcalfe niels B.J.Vollaard Department of Kinesiology CSU—San MarcosSan MarcosCAUSA Applied Sports TechnologyExercise and Medicine(A-STEM)Research CenterSwansea UniversitySwanseaUK Faculty of Health Sciences and Sport University of StirlingStirlingUK

Increases in power output and maximal oxygen consumption(V_O2max)occur in response to sprint interval exercise(SIE),but common use of“all-out”intensities presents a barrier for many ***,lower-body SIE is not feasible for all *** compared physiological and perceptual responses to supramaximal,but“nonall-out”SIE between leg and arm cycling ***-four active adults(mean±SD age:[25±7]y;cycling VO_(2)max:[39±7]mL·kg^(-1)·min^(-1))performed incremental exercise using leg(LCE)and arm cycle ergometry(ACE)to determine VO_(2)max and maximal work capacity(Wmax).Subsequently,they performed four 20 s bouts of SIE at 130% Wmax on the LCE or ACE at cadence=120-130 rev/min,with 2 min recovery between *** exchange data,heart rate(HR),blood lactate concentration(BLa),rating of perceived exertion(RPE),and affective valence were *** showed significantly lower(p0.42),and lowest affective valence recorded(2.0±1.8)was considered“good to fairly good”.Data show that non“all-out”ACE elicits lower absolute but higher relative HR and VO_(2) compared to *** aversive perceptual responses could make this non-all-out modality feasible for inactive adults.

关键词： High intensity interval training Upper body exercise Peak power output Oxygen uptake Blood lactate concentration

Investigation of Hexavalent Chromium Reduction in Strong Saline and Acidic Nitro-Phosphate Solutions

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Journal of Analytical Sciences, Methods and Instrumentation 2024年第1期14卷 1-13页

作者： Deniz Avsar niels Højmark Andersen Dag Øistein Eriksen Jon Petter Omtvedt Department of Chemistry University of Oslo Oslo Norway

Phosphorus fertilizers from less pure sedimentary sources become increasingly important, due to depletion of phosphorus from igneous rock of high quality. Consequently, robust methods with potential to remove various types of hazardous elements are required. Among such impurities, hexavalent chromium (Cr(VI)) is very likely to become a future challenge. Different industrial ways to treat phosphate rock are currently being practised, and we have here studied how chromium behaves when using the nitro-phosphate process. The reduction mechanism of Cr (VI) in nitric acid and phosphoric acid solutions was investigated by measuring redox potential and UV-VIS spectra. The results show that Cr (VI) is not stable in strong nitric acid solutions. Reduction of Cr (VI) species decreased with decreasing temperature, NO2 concentration, ionic strength and absence of light. These findings support the proposed reduction reaction:The reduction rate was observed proportional to the nitric acid decomposition: .

关键词： Nitro-Phosphate Fertilizers Chromium (VI) Reduction Chromium Speciation Ultraviolet-Visible Spectroscopy

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慢性肾脏病患者患病体验的质性研究

军事护理 2024年第8期41卷 74-77页

作者：申红霞黎敏仪赖美琦严斯静 Rianne van der Kleij niels Chavannes 广州医科大学护理学院广东广州510182 莱顿大学医学中心荷兰莱顿2300 RC

目的了解慢性肾脏病(chronic kidney disease,CKD)患者的患病体验,为构建个性化干预提供依据。方法采用现象学研究法,以目的抽样结合滚雪球抽样方法选取2021年10月至2022年7月河南省某三级甲等医院肾内科18例慢性肾脏病患者进行半结构... 详细信息

目的了解慢性肾脏病(chronic kidney disease,CKD)患者的患病体验,为构建个性化干预提供依据。方法采用现象学研究法,以目的抽样结合滚雪球抽样方法选取2021年10月至2022年7月河南省某三级甲等医院肾内科18例慢性肾脏病患者进行半结构式深度访谈,通过框架分析法和***软件进行资料分析。结果可归纳为5个主题:疾病确诊经历、症状困扰与日常生活改变、经济负担沉重、社会行为退缩和社交隔离和多样化支持需求。结论CKD患者在疾病过程中存在多维度问题和需求,医护人员应重视完善基层防治、推进健康科普,探索合适的心理干预策略以及运用远程技术进行CKD患者的延续性支持,提升其生活质量。

关键词：慢性肾脏病体验照护需求质性研究

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利用择形分子筛异构化亚甲基二苯胺

Chinese Journal of Catalysis 2024年第7期62卷 124-130页

作者： Sam Van Minnebruggen Ka Yan Cheung Trees De Baerdemaeker niels Van Velthoven Matthias Degelin Galahad O’Rourke Hiroto Toyoda Andree Iemhoff Imke Muller Andrei-Nicolae Parvulescu Torsten Mattke Jens Ferbitz 吴勤明肖丰收 Toshiyuki Yokoi Nils Bottke Dirk De Vos 巴斯夫股份有限公司膜分离、吸附、催化和光谱学可持续解决方案中心(cMACS) 比利时巴斯夫股份有限公司研究组德国东京工业大学纳米空间催化研究所横滨日本浙江大学化学系浙江杭州310028

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能... 详细信息

亚甲基二苯胺(MDA)被广泛用作生产聚氨酯和聚异氰脲酸酯的中间体.然而,当前MDA的生产工艺在控制(4,4’/(2,4’+2,2’))异构体比例方面还存在局限.其中,4,4’-MDA被认为是最有价值的异构体.尽管2,4'-MDA在市场上也有一定的需求,但如果能将其有效地转化为4,4'-MDA,将能显著提升其附加值.本文在使用苯胺的条件下,利用β分子筛等催化剂,通过双分子机制,可以选择性地将2,4'-MDA异构化为4,4'-MDA.尽管实验显示,多种酸性沸石具有较高的异构化活性,但MCM-68(具有MSE拓扑结构)的催化性能尤为出色,它不仅展现出高异构化活性,而且具有很好的选择性.MCM-68主要催化2,4'-MDA异构化为4,4'-MDA,而2,2'-MDA和低聚物的形成则可以忽略不计.本文还深入探讨了该择形作用的原因,并详细研究了酸位置在MSE分子筛孔道限制中的关键作用.

关键词：铝分布多相催化异构化亚甲基二苯胺聚氨酯择形