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A comparative genomic framework for the fish-tetrapod transition

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Science China(Life Sciences) 2021年第4期64卷 664-666页

作者： per Erik Ahlberg Department of Organismal Biology Uppsala University75236 UppsalaSweden

The evolution of tetrapods(land vertebrates)from lobe-finned fishes,nearly 400 million years ago,was a hugely important *** one thing,if these ancient fishes had not found a way to adapt to life out of the water,we humans would not *** investigate this event we can look at the fossil record,but that only tells us about changes in the skeleton.

关键词： skeleton record fish

Comparative analysis of planted and unplanted controls for assessment of rhizosphere priming effect

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Pedosphere 2022年第6期32卷 884-892页

作者： Jian LI per BENGTSON Department of Biology Microbial Ecology GroupLund UniversitySölvegatan 37Lund 22362(Sweden) Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences1799 Jimei RoadXiamen 361021(China)

The rhizosphere priming effect(RPE)is increasingly being considered to be an important regulator of soil organic matter(SOM)decomposition and nutrient turnover,with potential importance for the global CO_(2) *** a result,studies on the RPE have rapidly increased in number over the last few *** of these experiments have been performed using unplanted soil as the control,which could potentially lead to incorrect assessment of the ***,we performed a greenhouse experiment to investigate how the choice of control(i.e.,unplanted control and planted control)influenced the quantification of RPE on SOM decomposition and gross nitrogen(N)mineralization,and to link this to differences in microbial and abiotic soil properties between the two *** the planted control,planted seedlings were cut at soil surface 5 d before measurement of the *** RPE on SOM decomposition was positive in pine soil and almost 2-fold higher when calculated from the planted control than from the unplanted *** spruce soil,a negative RPE on SOM decomposition was found when calculated from the planted control,while the RPE was positive when calculated from the unplanted *** RPE on gross N mineralization was found when calculated from the planted control,while a positive RPE of more than 100%was found when calculated from the unplanted *** microbial biomass and growth rate were lower,while the inorganic N content was higher in the unplanted control than in the planted *** microbial community composition and potential enzyme activity in the planted treatment and planted control were similar,but they differed significantly from those in the unplanted *** results showed that the RPE varied widely depending on the choice of control;thus,we suggest that a planted control,in which the aboveground plant parts are removed only a few days before the measurement of RPE,should be used as the control when elucidating the RPE on belowground C and N

关键词： enzyme activity gross nitrogen mineralization microbial community composition nitrogen availability soil organic matter decomposition

Liver fibrosis in non-alcoholic fatty liver disease-diagnostic challenge with prognostic significance

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World Journal of Gastroenterology 2015年第39期21卷 11077-11087页

作者： per Stal Division of Gastroenterology and Hepatology Karolinska InstitutetDepartment of Digestive DiseasesHuddinge K63Karolinska University Hospital

Non-alcoholic fatty liver disease(NAFLD) is the mostcommon liver disease in the Western world, with a prevalence of 20%. In a subgroup of patients, inflammation, ballooning degeneration of hepatocytes and a varying degree of fibrosis may develop, a condition named non-alcoholic steatohepatitis. Advanced liver fibrosis(stage F3) and cirrhosis(stage F4) are histologic features that most accurately predict increased mortality in both liver-related and cardiovascular diseases. Patients with advanced fibrosis or cirrhosis are at risk for complications such as hepatocellular carcinoma and esophageal varices and should therefore be included in surveillance programs. However, liver disease and fibrosis are often unrecognized in patients with NAFLD, possibly leading to a delayed diagnosis of complications. The early diagnosis of advanced fibrosis in NAFLD is therefore crucial, and it can be accomplished using serum biomarkers(e.g., the NAFLD Fibrosis Score, Fib-4 Index or BARD) or non-invasive imaging techniques(transient elastography or acoustic radiation force impulse imaging). The screening of risk groups, such as patients with obesity and/or type 2 diabetes mellitus, for NAFLD development with these non-invasive methods may detect advanced fibrosis at an early stage. Additionally, patients with a low risk for advanced fibrosis can be identified, and the need for liver biopsies can be minimized. This review focuses on the diagnostic challenge and prognostic impact of advanced liver fibrosis in NAFLD.

关键词： Non-alcoholic fatty liver disease Fibrosis Mortality Biomarkers Elastography

Spinal and supraspinal control of motor function during maximal eccentric muscle contraction:Effects of resistance training

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Journal of Sport and Health Science 2018年第3期7卷 282-293页

作者： per Aagaard Department of Sports Science and Clinical Biomechanics University of Southern Denmark

Neuromuscular activity is suppressed during maximal eccentric(ECC)muscle contraction in untrained subjects owing to attenuated levels of central activation and reduced spinal motor neuron(MN)excitability indicated by reduced electromyography signal amplitude,diminished evoked H-reflex responses,increased autogenic MN inhibition,and decreased excitability in descending corticospinal motor *** ECC muscle force recorded during maximal voluntary contraction can be increased by superimposed electrical muscle stimulation only in untrained individuals and not in trained strength athletes,indicating that the suppression in MN activation is modifiable by resistance *** support of this notion,maximum ECC muscle strength can be increased by use of heavy-load resistance training owing to a removed or diminished suppression in neuromuscular ***(weeks to months)of heavy-load resistance training results in increased H-reflex and V-wave responses during maximal ECC muscle actions along with marked gains in maximal ECC muscle strength,indicating increased excitability of spinal MNs,decreased presynaptic and/or postsynaptic MN inhibition,and elevated descending motor ***,the use of supramaximal ECC resistance training can lead to selectively elevated V-wave responses during maximal ECC contraction,demonstrating that adaptive changes in spinal circuitry function and/or gains in descending motor drive can be achieved during maximal ECC contraction in response to heavy-load resistance training.

关键词： Corticospinal excitability Eccentric muscle contraction H-reflex Neuromuscular plasticity Resistance training V-wave

Factors shaping community structure of endophytic fungi–evidence from the Pinus-Viscum-system

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Fungal Diversity 2013年第3期60卷 55-69页

作者： Derek peršoh Systematische Botanik und Mykologie Ludwigs-Maximilians Universität MünchenMenzinger Straße 6780638 MünchenGermany Abteilung Mykologie Universität BayreuthUniversitätsstraße 30–NW I95440 BayreuthGermany

Endophytic fungal communities have been shown to be highly diverse in almost every host plant species analyzed so ***,the factors shaping their compositions are largely *** elucidate the impact of various factors,10 independent replicates of DNA extracts from each of 17 surface-sterilized leaf and stem samples were analyzed by pyrosequencing of fungal ITS1 rRNA gene ***,154 fungal OTUs(operational taxonomic units),represented by 953,385 sequences,were found in at least 2 samples from Viscum album *** and/or its host Pinus *** from earlier,cultivation-based assessments,the communities were dominated by OTUs related to the genus Mortierella and OTUs not assignable to a certain fungal ***,Ascomycota were still the most diverse group in terms of OTU richness and already hypothesized organ and host preferences of certain endophytic Xylariaceae isolated from the Pinus-Viscum-system could be *** species and organ type were also the major factors shaping the detected fungal *** two plant species clearly differed according to the endophytic fungal communities,but only stems and needles of Pinus were inhabited by significantly different fungal ***,only the 1 and 3 year old stem sections differed according to the endophytic fungal community,while differently aged leaves of both plants were indistinguishable in this *** of the organs had no impact on fungal communities in Pinus,but shorter internodes and smaller leaves showed at least a tendency to differ from the corresponding larger organs in *** communities also differed slightly between the two sampling sites,lying 200 km apart,and between the three sampling *** the samples were drawn within 15 days,this finding indicates that seasonal shifts clearly outweigh aging effects in host plant with perennial *** results therefore provide strong evidence against a linear developm

关键词： Endophytic fungi Pyrosequencing Host preference Stems Leaves Organ age Pinus sylvestris Viscum album Genetic abundance Name assignment

Plant-associated fungal communities in the light of meta’omics

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Fungal Diversity 2015年第6期75卷 1-25页

作者： Derek peršoh Ruhr-Universität Bochum AG GeobotanikGebäude ND 03/170Universitätsstraße 15044780 BochumGermany

Approaches for the cultivation-independent analysis of microbial communities are summarized as meta’omics,which predominantly includes metagenomic,-transcriptomic,-proteomic and-metabolomic *** have shown that endophytic,root-associated and soil fungal communities are strongly shaped by associated plant *** impact of plant identity on the composition of its litterssociated fungal community remains to be disentangled from the impact of litter *** composition of the plant community also shapes the fungal *** strikingly,adjacent plant species may share mycorrhizal symbionts even if the plants usually have different types of mycorrhizal fungi associated with them(ectomycorrhizal,ericoid and arbuscular mycorrhizal fungi).Environmental parameters weakly explain fungal community composition globally,and their effect is inconsistent at local and regional *** in similarity among communities with increasing distance(*** decay)has been reported from local to global *** pattern is only exceptionally caused by spatial dispersal limitation of fungal propagules,but mostly due to the inability of the fungi to establish at the particular locality(*** filtering or competitive exclusion).Fungal communities usually undergo pronounced seasonal changes and also differ between consecutive *** indicates that development of the communities is usually not solely ***’omic studies challenge the classical view of plant litter *** show that mycorrhizal and(previously)endophytic fungi may be involved in plant litter decomposition and only partly support the idea of a succession from an Ascomycota to a Basidiomycota-dominated ***,vertical separation of saprotrophic and mycorrhizal species in soil and sequential degradation from easily accessible to‘recalcitrant’plant compounds,such as lignin,can probably not be *** current models of litter decomposition may

关键词： Meta’omics Metaomics Fungal community Metagenomics Metaproteomics Metatranscriptomics Metametabolomics Phyllosphere fungi Endophytic fungi Litter decomposition Decomposer fungi Root-associated fungi Arbuscular mycorrhiza Ectomycorrhiza Ericoid mycorrhiza Soil fungi Functional diversity Environmental processes Distance decay Environmental filtering Saisonality Temporal shift Fungal traits

Artificial intelligence-based predictive model of nanoscale friction using experimental data

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Friction 2021年第6期9卷 1726-1748页

作者： Marko perČIĆ Saša ZELENIKA Igor MEZIĆ University of Rijeka Faculty of Engineering51000 RijekaCroatia University of Rijeka Centre for Micro-and Nanosciences and Technologies&Center for Artificial Intelligence and Cybersecurity51000 RijekaCroatia University of California Santa Barbara Department of Mechanical EngineeringSanta BarbaraCA 93105USA

A recent systematic experimental characterisation of technological thin films,based on elaborated design of experiments as well as probe calibration and correction procedures,allowed for the first time the determination of nanoscale friction under the concurrent influence of several process parameters,comprising normal forces,sliding velocities,and temperature,thus providing an indication of the intricate correlations induced by their interactions and mutual *** created the preconditions to undertake in this work an effort to model friction in the nanometric domain with the goal of overcoming the limitations of currently available models in ascertaining the effects of the physicochemical processes and phenomena involved in nanoscale *** to the stochastic nature of nanoscale friction and the relatively sparse available experimental data,meta-modelling tools fail,however,at predicting the factual *** on the acquired experimental data,data mining,incorporating various state-of-the-art machine learning(ML)numerical regression algorithms,is therefore *** results of the numerical analyses are assessed on an unseen test dataset via a comparative statistical *** is therefore shown that the black box ML methods provide effective predictions of the studied correlations with rather good accuracy levels,but the intrinsic nature of such algorithms prevents their usage in most practical *** programming-based artificial intelligence(AI)methods are consequently finally *** the marked complexity of the analysed phenomena and the inherent dispersion of the measurements,the developed AI-based symbolic regression models allow attaining an excellent predictive performance with the respective prediction accuracy,depending on the sample type,between 72%and 91%,allowing also to attain an extremely simple functional description of the multidimensional dependence of nanoscale friction on the studied variable process param

关键词： nanoscale friction thin films data mining machine learning(ML) predictive artificial intelligence(AI)-based model

Androgen deprivation therapy and side effects:are GnRH antagonists safer?

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Asian Journal of Andrology 2021年第1期23卷 3-10页

作者： Stephen J Freedland per-Anders Abrahamsson Division of Urology Department of SurgeryCedars-Sinai Medical CenterLos AngelesCA 90048USA Section of Urology Durham VA Medical CenterDurhamNC 27705USA Department of Urology SkSne University HospitalLund UniversityMalmo 20502Sweden.

Androgen deprivation therapy(ADT)with gonadotropin-releasing hormone(GnRH)agonists and antagonists is the mainstay of advanced prostate cancer *** drug classes decrease levels of luteinizing hormone and follicle-stimulating hormones(FSH),thereby lowering testosterone to castrate *** is associated with adverse events(AEs),including cardiovascular(CV)disorders,bone fractures,metabolic dysfunction,and impaired cognitive *** literature review discusses these AEs,with a focus on CV and bone-related events.A hypothesis-generating meta-analysis of six clinical trials showed a potentially increased risk for CV disorders with GnRH agonists versus the GnRH antagonist *** no study has directly compared GnRH agonists versus antagonists with a primary CV outcome,one hypothesis for this observation is that GnRH agonists lead to initial surges in FSH that may negatively impact CV health,whereas antagonists do *** agonists are associated with metabolic and cognitive AEs and while data are lacking for GnRH antagonists,no differences in risk are *** common AEs with ADT include injection site reactions,which are much more common with degarelix than with GnRH agonists,which may reflect differing administration and injection *** studies are needed to further evaluate and compare the safety profiles of GnRH agonists and antagonists,especially in patients with pre-existing CV disease and other *** should carefully evaluate benefits and risks when prescribing ADT and ensure that side effects are well managed.

关键词： androgen antagonists metabolic syndrome prostate cancer safety

Simulation of the response of base-isolated buildings under earthquake excitations considering soil flexibility

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Earthquake Engineering and Engineering Vibration 2012年第3期11卷 359-374页

作者： Sayed Mahmoud per-Erik Austrell Robert Jankowski Department of Construction Sciences Division of Structural MechanicsLund University Faculty of Engineering at Mataria Helwan University Faculty of Civil and Environmental Engineering Gdansk University of Technology

The accurate analysis of the seismic response of isolated structures requires incorporation of the flexibility of supporting soil. However, it is often customary to idealize the soil as rigid during the analysis of such structures. In this paper, seismic response time history analyses of base-isolated buildings modelled as linear single degree-of-freedom （SDOF） and multi degree-of-freedom （MDOF） systems with linear and nonlinear base models considering and ignoring the flexibility of supporting soil are conducted. The flexibility of supporting soil is modelled through a lumped parameter model consisting of swaying and rocking spring-dashpots. In the analysis, a large number of parametric studies for different earthquake excitations with three different peak ground acceleration （PGA） levels, different natural periods of the building models, and different shear wave velocities in the soil are considered. For the isolation system, laminated rubber bearings （LRBs） as well as high damping rubber bearings （HDRBs） are used. Responses of the isolated buildings with and without SSI are compared under different ground motions leading to the following conclusions：（1） soil flexibility may considerably influence the stiff superstructure response and may only slightly influence the response of the flexible structures; （2） the use of HDRBs for the isolation system induces higher structural peak responses with SSI compared to the system with LRBs; （3） although the peak response is affected by the incorporation of soil flexibility, it appears insensitive to the variation of shear wave velocity in the soil; （4） the response amplifications of the SDOF system become closer to unit with the increase in the natural period of the building, indicating an inverse relationship between SSI effects and natural periods for all the considered ground motions, base isolations and shear wave velocities; （5） the incorporation of SSI increases the number of significant cycles of large amplitude acce

关键词： base-isolated buildings rubber bearings earthquakes soil-structure interaction