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The role of mechanotransduction versus hypoxia during simulated orthodontic compressive strain——an in vitro study of human periodontal ligament fibroblasts

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International Journal of Oral Science 2019年第4期11卷 315-324页

作者： niklas ullrich Agnes Schroder Jonathan Jantsch Gerrit Spanier Peter Proff Christian Kirschneck University Medical Centre of Regensburg Franz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany Department of Orthodontics University Medical Centre of RegensburgFranz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany Department of Medical Microbiology and Hygiene University Medical Centre of RegensburgFranz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany Department of Cranio-Maxillo-Facial Surgery University Medical Centre of RegensburgFranz-Josef-Strauβ-Allee 11D-93053 RegensburgGermany

During orthodontic tooth movement(OTM)mechanical forces trigger pseudo-inflammatory,osteoclastogenic and remodelling processes in the periodontal ligament(PDL)that are mediated by PDL fibroblasts via the expression of various signalling *** far,it is unknown whether these processes are mainly induced by mechanical cellular deformation(mechanotransduction)or by concomitant hypoxic conditions via the compression of periodontal blood *** primary PDL fibroblasts were randomly seeded in conventional six-well cell culture plates with O2-impermeable polystyrene membranes and in special plates with gas-permeable membranes(Lumox?,Sarstedt),enabling the experimental separation of mechanotransducive and hypoxic effects that occur concomitantly during *** simulate physiological orthodontic compressive forces,PDL fibroblasts were stimulated mechanically at 2 g·cm?2 for 48 h after 24 h of *** quantified the cell viability by MTT assay,gene expression by quantitative real-time polymerase chain reaction(RT-qPCR)and protein expression by western blot/enzyme-linked immunosorbent assays(ELISA).In addition,PDL-fibroblast-mediated osteoclastogenesis(TRAP+cells)was measured in a 72-h coculture with RAW264.7 *** expression of HIF-1α,COX-2,PGE2,VEGF,COL1A2,collagen and ALPL,and the RANKL/OPG ratios at the mRNA/protein levels during PDL-fibroblast-mediated osteoclastogenesis were significantly elevated by mechanical loading irrespective of the oxygen supply,whereas hypoxic conditions had no significant additional *** cellular–molecular mediation of OTM by PDL fibroblasts via the expression of various signalling molecules is expected to be predominantly controlled by the application of force(mechanotransduction),whereas hypoxic effects seem to play only a minor *** the context of OTM,the hypoxic marker HIF-1αdoes not appear to be primarily stabilized by a reduced O2 supply but is rather stabilised mechanically.

关键词： RAW264.7 periodontal mec

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Effects of age on marathon finishing time among male amateur runners in Stockholm Marathon 1979–2014

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Journal of Sport and Health Science 2016年第3期5卷 349-354页

作者： niklas Lehto Department of Health Sciences Luled University of Technology

Purpose: The purpose of the present study was to investigate the age-related changes in the endurance performance among male amateur marathon ***: Subjects were taken from the 36 Stockholm Marathons held from 1979 through 2014, and age and finishing time were analyzed for a total of 312,342 male ***: The relation was found to be a second-order polynomial, t = a + bx + cx^2, which models 99.7% of the variation in the average running time t as a function of age x. The model shows that the marathon performance of the average runner improves up to age 34.3 ± 2.6 years, thereafter,the performance starts to decline. A quantification of the age's influence on running time shows that it accounts for 4.5% of the total variance seen in the performance ***: These outcomes indicate that the effect of age on performance in endurance running events is clearly measurable, quantifiable, and possible to describe. At the same time the findings indicate that other factors, such as training, affect the performance more. A comparison with the elite showed peak performance at the same age, but the rates of change in performance with age, improvement as well as degradation, was found to be higher among the elite.

关键词： Aerobic exercise Health Non-elite Recreational runner Regression modeling Running

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Application of CRISPR/Cas-mediated base editing for directed protein evolution in plants

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Science China(Life Sciences) 2020年第4期63卷 613-616页

作者： niklas Capdeville Patrick Schindele Holger Puchta Botanical Institute Molecular Biology and BiochemistryKarlsruhe Institute of TechnologyKarlsruhe 76131Germany

Breeding for improved cultivars of existing crops depends mainly on the available amount of genetic variability in yield or quality related *** thousands of years,humans have relied on naturally occurring mutations to recombine and select improved *** chemical or physical mutagens,the amount and range of mutations could be increased,accelerating the development of new ***,naturally occurring or randomly induced mutations lead to unpredictable breeding outcomes and therefore necessitate tedious rounds of backcrossing to eventually produce useful phenotypes(Pacher and Puchta,2017).

关键词： breeding crops cultivar

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Transformation of the TiNi Alloy Microstructure and the Mechanical Properties Caused by Repeated B2-B190' Martensitic Transformations

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Acta Metallurgica Sinica(English Letters) 2015年第10期28卷 1230-1237页

作者： Anna Churakova Dmitry Gunderov Alexander Lukyanov niklas Nollmann Institute of Molecule and Crystal Physics RAS Ufa State Aviation Technical University Institute of Materials Physics University of Münster

The influences of thermal cycling treatment in the temperature range of B2-B19 martensitic transformations（-150 to 150 °C） on the Ti Ni alloy structure and properties were studied. Different states named the initial coarse-grained（CG） state, the ultrafine-grained（UFG） state after ECAP（with a grain size of 200 nm）, the state after ECAP and cold upsetting by 30% were considered. The results show that the microhardness and the strength increase in all the three *** to the XRD analysis, a more significant increment in the dislocation density, resulting from thermal cycling, is observed in the UFG alloy than in the CG alloy.

关键词： Thermal cycling TiNi alloy Equal-channel angular pressing Martensitic transformation

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Do plants explore habitats before exploiting them? An explicit test using two stoloniferous herbs

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Chinese Science Bulletin 2012年第19期57卷 2425-2432页

作者： PENG YouHong niklas KarlJ SUN ShuCun Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Department of PlantBiology Cornefl UniversityIthacaNY14850USA Department of Biology Nanjing UniversityNanjing 210093China

We tested whether the processes of exploration and exploitation can be explicitly distinguished as plants grow and develop within a habitat using two stoloniferous clonal herbs,Hydrocotyle sibthorpioides(Umbelliferae) and Potentilla anserina(Rosaceae).Ramets were planted in four circular trays differing in *** replicate from each diameter-group was sampled at intervals corresponding to plant coverage of the trays,and plant biomass allocation to leaves,stolons,and roots and internode length were *** both species,at early sampling times(when the smallest trays were full),total plant biomass and ramet number were larger in the smaller trays than in the larger ***,this trend was reversed for plants collected at later *** ***,leaf mass ratios(leaf mass to total plant mass) were significantly greater,but stolon mass ratios(stolon mass to total plant mass) were less in the small trays than in the larger ones,particularly during the early stages of the ***,for ***,leaf mass ratios decreased in the smaller trays but increased in the larger ones as the experiment *** mass ratios showed contrasting pattern to leaf mass ratios for both species;stolon mass ratios were significantly smaller in the smaller trays than in the larger ones,although there were no obvious patterns during the course of the *** addition,for both species,internode length was shorter but the number of ramets was greater in the smaller trays at early sampling *** conclude that plants invest greater biomass in resource-exploring organs(stolons) than in resource-exploiting organs(leaves or roots) as they initially establish in a *** relatively lower plant productivity in the largest trays at early sampling times presumably reflects the cost of exploration prior to resource exploitation and utilization.

关键词：草本植物匍匐茎栖息地测试采样时间早期阶段物探实验过程

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Host plant choice in the comma butterfly-larval choosiness may ameliorate effects of indiscriminate oviposition

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Insect Science 2014年第4期21卷 499-506页

作者： Gabriella Gamberale-Stille Lina Soderlind niklas Janz Soren Nylin Department of Zoology Stockholm University 106 92 Stockholm Sweden

In most phytophagous insects, the larval diet strongly affects future fitness and in species that do not feed on plant parts as adults, larval diet is the main source of nitrogen. In many of these insect-host plant systems, the immature larvae are considered to be fully dependent on the choice of the mothers, who, in turn, possess a highly developed host recognition system. This circumstance allows for a potential mother-offspring conflict, resulting in the female maximizing her fecundity at the expense of larval performance on suboptimal hosts. In two experiments, we aimed to investigate this relationship in the polyphagous comma butterfly, Polygonia c-album, by comparing the relative acceptance of low- and medium-ranked hosts between females and neonate larvae both within individuals between life stages, and between mothers and their offspring. The study shows a variation between females in oviposition acceptance of low-ranked hosts, and that the degree of acceptance in the mothers correlates with the probability of acceptance of the same host in the larvae. We also found a negative relationship between stages within individuals as there was a higher acceptance of lower ranked hosts in females who had abandoned said host as a larva. Notably, however, neonate larvae of the comma butterfly did not unconditionally accept to feed from the least favorable host species even when it was the only food source. Our results suggest the possibility that the disadvantages associated with a generalist oviposition strategy can be decreased by larval participation in host plant choice.

关键词： host plant choice insect-host plant interaction mobility oviposition behav-ior parent-offspring conflict specialization

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The relationship between relative growth rate and whole-plant C:N:P stoichiometry in plant seedlings grown under nutrient-enriched conditions

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Journal of Plant Ecology 2011年第3期4卷 147-156页

作者： Youhong Peng Karl J.niklas Shucun Sun ECORES Lab Chengdu Institute of BiologyChinese Academy of Sciences9 Section 4 Renminnan RoadChengdu 610041China Department of Plant Biology Cornell UniversityIthacaNY 14850USA Department of Biology Nanjing UniversityNanjing 210093China

Aims Recent theories indicate that N is more in demand for plant growth than P;therefore,N concentration and N:C and N:P ratios are predicted to be positively correlated with relative growth rate(RGR)in plants under nutrient-enriched *** prediction was tested in this *** We examined the whole-plant concentrations of C,N and P and RGR,as well as the relationship between RGR and the concentrations and the ratios of N:C,P:C and N:P,for different harvest stages(the days after seed germination)of the seedlings of seven shrub species and four herbaceous species grown in N and P non-limiting *** relationships among plant size,nutrient concentrations and ratios were subsequently *** Findings RGR was positively correlated with N concentration and the ratios of N:PandN:C when the data were pooled for all species and for each shrub species,but not for individual herbaceous ***,the relationship between RGR and P concentration and P:C was not significantly correlated for either shrubs or *** variation of N among harvest stages and species was much greater than that of P,and the variation in N:P ratio was determined primarily by changes in N *** shrub species differed from the herbaceous species in their N and P concentrations,nutrient ratios and in intraspecific relationships between RGR and nutrient *** differences possibly reflect differences in the capacity for P storage and biomass allocation *** general,our data support recent theoretical predictions regarding the relationship between RGR and C:N:P stoichiometry,but they also show that species with different life forms differ in the relationships among RGR and C:N:P stoichimetries.

关键词： C:N:P stoichiometry RGR growth rate hypothesis life forms seedlings screening experiment

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Molecular insights of exercise therapy in disease prevention and treatment

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2564-2597页

作者： David Walzik Tiffany Y.Wences Chirino Philipp Zimmer niklas Joisten Division of Performance and Health(Sports Medicine) Institute for Sport and Sport ScienceTU Dortmund University44227 DortmundNorth Rhine-WestphaliaGermany Division of Exercise and Movement Science Institute for Sport ScienceUniversity of Göttingen37075 GöttingenLower SaxonyGermany

Despite substantial evidence emphasizing the pleiotropic benefits of exercise for the prevention and treatment of various diseases,the underlying biological mechanisms have not been fully *** exercise benefits have been attributed to signaling molecules that are released in response to exercise by different tissues such as skeletal muscle,cardiac muscle,adipose,and liver *** signaling molecules,which are collectively termed exerkines,form a heterogenous group of bioactive substances,mediating inter-organ crosstalk as well as structural and functional tissue *** scientific endeavors have focused on identifying and characterizing new biological mediators with such ***,some investigations have focused on the molecular targets of exerkines and the cellular signaling cascades that trigger adaption processes.A detailed understanding of the tissue-specific downstream effects of exerkines is crucial to harness the health-related benefits mediated by exercise and improve targeted exercise programs in health and ***,we review the current in vivo evidence on exerkine-induced signal transduction across multiple target tissues and highlight the preventive and therapeutic value of exerkine signaling in various *** emphasizing different aspects of exerkine research,we provide a comprehensive overview of(i)the molecular underpinnings of exerkine secretion,(ii)the receptor-dependent and receptor-independent signaling cascades mediating tissue adaption,and(iii)the clinical implications of these mechanisms in disease prevention and treatment.

关键词： prevention treatment collective

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Dynamics in large generators due to oval rotor and triangular stator shape

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Acta Mechanica Sinica 2011年第1期27卷 18-27页

作者： niklas L.P.Lundstrm Jan-Olov Aidanp Division of Solid Mechanics Department of Applied Physics and Mechanical EngineeringLuleUniversity of Technology

Earlier measurements in large synchronous generators indicate the existence of complex whirling motion, and also deviations of shape in both the rotor and the stator. These non-symmetric geometries produce an attraction force between the rotor and the stator,called unbalanced magnetic pull（UMP）.The target of this paper is to analyse responses due to certain deviations of shape in the rotor and the *** particular,the perturbation on the rotor is considered to be of oval character,and the perturbations of the stator are considered *** numerical and analytical methods it is concluded for which generator parameters harmful conditions,such as complicated whirling motion and high amplitudes,will *** maintenance of hydro power generators the shapes of the rotor and stator are frequently *** results from this paper can be used to evaluate such measurements and to explain the existence of complex whirling motion.

关键词： Generator · Rotor · Dynamics · Asymmetric · Hydropower

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Sustainability of microporous polymers and their applications

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Science China Chemistry 2017年第8期60卷 1033-1055页

作者： Tamara L.Church Alma Berenice Jasso-Salcedo Fredrik Bjrnerbck niklas Hedin Department of Materials and Environmental Chemistry Stockholm University SE-106 91 Stockholm Sweden

Microporous polymers(MPs) are studied for their intriguing chemistry and physics as well as their potential application in catalytic transformations, gas-separation processes, water purification and so on. Here, we critically review MPs with respect to the sustainability aspects of their synthesis as well as their applications that have sustainable character. Some MPs have been synthesized from monomers derived from biomass resources, but there is certainly a large potential for further *** are also opportunities to improve the sustainability of MP synthesis in terms of the use of solvents, catalysts, and related aspects. The applications of MPs in processes related to sustainability depend upon multiple properties. A rich and flexible chemistry is important to applications as catalysts for, among other useful reactions, the photoreduction of CO_2 and selective oxidation. The(ultra)micropore volume of MPs are crucial in gas-separation applications such as CO_2 capture, and the chemisorption of CO_2 on MP-tethered alkylamines could offer a means to remove that gas from dilute mixtures. When it comes to the storage of H_2 and CH_4 in MPs for onboard use in fuel cell or biogas cars, volumetric capacity is paramount, meaning that the density of the MPs must be considered. Finally, for use in separation and purifications from liquid mixtures(aqueous or hydrocarbon-based), crosslinked MPs are more limited than the solution-processable MPs that can be more easily processed into films and membranes.

关键词： microporous polymers biomass sustainability CO2 capture catalysis H2 storage CH4 storage separation purification

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