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Carbon dioxide fluxes of tundra vegetation communities on an esker top in the low-Arctic

Advances in Polar Science 2020年第3期31卷 167-177页

作者： peter m.LAFLEUR A.Brett CAmPEAU Sohee KANG School of the Environment Trent UniversityPeterboroughOntarioCanada Geography Department Trent UniversityPeterboroughOntarioCanada Department of Computer and mathematical Sciences University of Toronto ScarboroughTorontoOntarioCanada

Previous studies have shown that carbon dioxide fluxes vary considerably among Arctic environments and it is important to assess these differences in order to develop our understanding of the role of Arctic tundra in the global carbon cycle. Although many previous studies have examined tundra carbon dioxide fluxes, few have concentrated on elevated terrain(hills and ridge tops) that is exposed to harsh environmental conditions resulting in sparse vegetation cover and seemingly low productivity. In this study we measured carbon dioxide(CO2) exchange of four common tundra communities on the crest of an esker located in the central Canadian low-Arctic. The objectives were to quantify and compare CO2 fluxes from these communities, investigate responses to environmental variables and qualitatively compare fluxes with those from similar communities growing in less harsh lowland tundra environments. measurements made during July and August 2010 show there was little difference in net ecosystem exchange(NEE) and gross ecosystem production(GEP) among the three deciduous shrub communities, Arctous alpina, Betula glandulosa and Vaccinium uliginosum, with means ranging from -4.09 to -6.57 μmol·m^-2·s^-1 and -7.92 to -9.24 μmol·m^-2·s^-1, respectively. Empetrum nigrum communities had significantly smaller mean NEE and GEP(-1.74 and -4.08 μmol·m^-2·s^-1, respectively). Ecosystem respiration(ER) was similar for all communities(2.56 to 3.03 μmol·m^-2·s^-1), except the B. glandulosa community which had a larger mean flux(4.66 μmol·m^-2·s^-1). Overall, fluxes for these esker-top communities were near the upper range of fluxes reported for other tundra communities. ER was related to soil temperature in all of the communities. Only B. glandulosa GEP and ER showed sensitivity to a persistent decline in soil moisture throughout the study. These findings may have important implications for how esker tops would be treated in construction of regional carbon budgets and for predicting the im

关键词： tundra carbon exchange net ecosystem exchange gross ecosystem productivity ecosystem respiration low-Arctic esker top xerophytes

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Associations of blood biomarkers with glomerular filtration rate in patients with TIA and stroke: population-based study

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Stroke & Vascular Neurology 2021年第1期6卷 48-56页

作者： Dearbhla m.Kelly Linxin Li Annette I Burgess Deborah L Poole Julia m Duerden peter m.rothwel. Wolfson Centre for the Prevention of Stroke and Dementia Nuffield Department of Clinical NeurosciencesOxford UniversityOxfordUK

Background and purpose Non-traditional risk factors such as chronic inflammation,oxidative stress and thrombogenic factors are believed to contribute to the excess stroke risk in chronic kidney disease(CKD)by triggering vascular injury and endothelial *** aimed to determine how well a panel of biomarkers representative of these factors would correlate with estimated glomerular filtration rate(eGFR)in patients with recent transient ischaemic attack(TIA)or *** also investigated whether eGFR would confound previously reported associations between biomarkers and *** We studied a panel of 16 blood biomarkers related to inflammation,thrombosis,atherogenesis and cardiac or neuronal cell damage in TIA or ischaemic stroke in a population-based study(Oxford Vascular Study).Biomarker levels were log-transformed and correlated with eGFR,adjusted for *** proportional hazard models were used for survival *** Among 1297 patients with TIA or stroke,52.7%(n=684)of patients had CKD(eGFRmL/min/1.73 m^(2)).There was a moderate correlation between log-eGFR and the log-transformed soluble tumour necrosis factor receptor-1(R^(2)=0.21),attenuating with adjustment for age(R^(2)=0.12).There were moderate-to strong correlations with markers of cardiac injury,N-terminal pro-brain natriuretic peptide and heart-type fatty acid binding protein(hFABP,R2=0.14 and 0.34,respectively).The strongest correlation after adjustment for age was between hFABP and eGFR(R^(2)=0.20).Adjusting for eGFR did not impact any biomarker associations with *** Correlations between biomarkers related to inflammation and thrombosis with renal dysfunction in the setting of cerebrovascular events were generally modest after adjustment for age,suggesting that putative risk factors such as chronic inflammation or coagulopathy are unlikely to be important stroke mechanisms in patients with CKD.

关键词： inflammation patients mortality

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Analysis of Cartilage Creep Recovery Using a Highly Dynamic Closed-loop Test System

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Journal of Bionic Engineering 2018年第6期15卷 1057-1066页

作者： Josef Stolberg-Stolberg peter Foehr Iris Pflieger Lara Kuntz Constantin von Deimling Andreas Obermeier peter m. Prodinger Christian U. Grosse Rainer Burgkart Department of Orthopaedics and Sports Orthopaedics Klinikum rechts der Isar Technical University of Munich Munich 81675 Germany Department of Trauma Hand and Reconstructive Surgery University Hospital Muenster Albert-Schweitzer-Campus 1 Muenster 48149 Germany Chair of Non-destructive Testing Technical University of Munieh Munich 81245 Germany Department of Trauma Surgery Trauma Center Murnau Murnau 82418 Germany

The aim of this study was to analyze cartilage creep and creep recovery after static and cyclic loading. Up to now technical limitations have hindered the measurement of creep recovery. For this reason, we developed a closed loop micro creep and creep-recovery indentation test system with active force control. Bovine osteochondral explants were tested under static （110 kPa） and cyclic （100 cycles, 350 kPa/35 kPa, 1 Hz） loading conditions and subsequently creep recovery was measured. The cartilage thickness was determined using needle indentation. For static loading, the creep and creep-recovery rates were significantly different during the first 60 seconds （p 〈 0.05）. Cyclic loading was assessed for the medial and lateral patella and resulted in a physiological patellar cartilage strain of 7.7% ± 2.6% and 8.2% ± 2.7%, respectively. We recorded a creep recovery of 97.8% ±2.1% for the medial and 98.3% ± 2.4% for the lateral patella. The advantage of this study over earlier in vitro studies is that we recorded creep-recovery profiles with an actively controlled setup. This allowed us to analyze creep recovery immediately after removing the creep load, in contrast to mRI-based in vivo studies. In future, the presented method will enable us to quantify spatial variations within articular joints.

关键词： articular cartilage indentation creep recovery arthritis regenerative tissue

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Hypervelocity Impacts and Exposed Lithospheric mantle: A Way to Recognize Large Terrestrial Impact Basins?

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Journal of Earth Science 2019年第3期30卷 451-459页

作者： peter Olds Chemistry Faculty College of Alameda

On the moon and mars olivine of probable mantle origin is detected at rims of large Late Heavy Bombardment(LHB) age impact basins for which excavation depth estimates exceed crustal thickness estimates. But lunar Crisium size impact basins are not recognized on Earth nor expected in the Phanerozoic from conventional interpretations of crater size frequency distributions. In this study several large circular to elliptical basin structures on Earth, for which hypothesized impact excavation depth would greatly exceed crustal thickness, are examined for the presence of exposed lithospheric mantle, expressed as ophiolite, at the rims. Three Phanerozoic impact basins, modified by plate tectonics and tentatively correlated with "ophiolite obduction" plus global extinction events, are proposed here. These tentatively suggested Phanerozoic impact basins are:(1) Yucatan Basin/Puerto Rico Trench with a Greater Antilles ophiolite rim. Cretaceous-Paleogene Boundary global extinction may correlate with maastrichtian ophiolite obduction in Southeast Cuba.(2) Loyalty Basin with a New Caledonia ophiolite plus d’Entrecasteaux Ridge rim. Late Eocene global extinction may correlate with obduction of the New Caledonia Peridotite Nappe.(3) Sulu Sea Basin with a Palawan, Sabah etc. ophiolite rim. The middle miocene Disruption Event may correlate with ophiolite obduction plus ophiolitic mélange emplacement in Sabah and in Palawan. These originally circular to elliptical belts of exposed lithospheric mantle may serve as strain markers for relative plate motions in the vicinity of plate boundaries during post-impact geologic times. It is further speculated that plate boundaries may be initiated and/or modified by such impacts.

关键词： olivine mantle impact basin ophiolite obduction mass extinction

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mass spectrometry based proteomics,background,status and future needs

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Protein & Cell 2012年第9期3卷 641-647页

作者： peter Roepstorff Department of Biochemistry and molecular Biology University of Southern Denmark Campusvej 55DK 5230 Odense MDenmark

An overview of the background for proteomics and a description of the present state of art are given with a description of the main strategies in *** advantages and limitations of the two major strategies,2D-gel based and LC-mS based,are discussed and a combination for the two,CeLC-mS is described.A number of challenging problems which have been solved using different proteomics strategies including the advantage of organell enrichment or modifications specific peptide isolation to get deeper into the proteome are *** the present status and future needs discussed.

关键词： proteomics 2D-PAGE LC-mS isoforms phosphorylation

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measurement of inter-particle forces by an interfacial force microscope

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Particuology 2010年第5期8卷 400-406页

作者： Qing Huang Asghar mesbah-Nejad Seyed m. Tadayyon peter Norton Hui Zhang Jesse Zhu Particle Technology Research Centre Department of Chemical and Biochemical Engineering The University of Western Ontario London Ontario N6A 5B9 Canada Department of Electrical and Computer Engineering The University of Western Ontario London Ontario N6A 5B9 Canada Department of Chemistry The University of Western Ontario London Ontario N6A 589 Canada

An interfacial force microscope （IFm） was employed to measure the inter-particle forces between two individual glass beads with diameters varying from 8 to 20 μm. With the feedback function of IFm turned off, attractive forces were obtained. The forces varied in the range of 0.1-0.34 μN, and their validity was confirmed by a theoretical analysis of the van der Waals force between the same glass beads. With the feedback function switched on, no attractive forces between particles were detected by the IFm when the probe approached the sample substrate. This may be attributed to the dramatic change of the attractive forces within a very short separation distance and/or the relatively poor signal-to-noise ratio of the IFm.

关键词： Inter-particle forcesvan der Waals forceInterracial force microscopeFine powder

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Clinical and dietary predictors of common carotid artery intima media thickness in a population with type 1 and type 2 diabetes: A cross-sectional study

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World Journal of Diabetes 2017年第1期8卷 18-27页

作者： Kristina S petersen Jennifer B Keogh peter J meikle manohar L Garg peter m Clifton School of Pharmacy and medical Sciences University of South Australia Baker IDI Heart and Diabetes Institute Nutraceuticals Research Group University of NewcastleCallaghan

AIm To determine the clinical and dietary predictors of common carotid artery intima media thickness(CCA ImT) in a cohort of subjects with type 1 and type 2 diabetes. mETHODS Participants with type 1(n = 23) and type 2 diabetes(n = 127) had mean and mean maximum CCA ImT measured using B mode ultrasound. Dietary intake was measured using a food frequency questionnaire. Clinical and dietary predictors of mean and mean maximum CCA ImT were determined using linear regression analysis adjusted for potential confounders. RESULTS The main predictors of mean and mean maximum CCA ImT were age and weight. After multivariate adjustment there were no dietary predictors of CCA ImT. However,in subjects that were not prescribed a lipid lowering medication alcohol consumption was positively associated with CCA ImT after multivariate adjustment. No difference existed in CCA ImT between subjects with type 1 or type 2 diabetes once age was adjusted for. CONCLUSION CCA ImT was predominantly predicted by age and weight in these subjects with diabetes. The finding that CCA ImT was not different between people with type 1 and type 2 diabetes warrants further investigation in a larger cohort.

关键词： Diabetes Carotid intima media thickness Arterial structure Diet Lipidomics Carotenoids

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pHairyRed： A Novel Binary Vector Containing the DsRed2 Reporter Gene for Visual Selection of Transgenic Hairy Roots

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molecular Plant 2011年第3期4卷 537-545页

作者： meng-Han Lin peter m. Gresshoff Arief Indrasumunar Brett J. Ferguson Australian Research Council Centre of Excellence for Integrative Legume Research The University of Queensland St Lucia Brisbane QLD 4072 Australia

We developed a new plant transformation vector, pHairyRed, for enabling high throughput, non-destructive selection of Agrobacterium rhizogenes-mediated ＇hairy-root＇ transformation, pHairyRed allows easy in planta visualiza- tion of transgenic tissue with minimal disturbance to the plant. The DsRed2 reporter gene, encoding a red fluorescent protein, was cloned to yield pHairyRed （harbouring a multiple cloning site）, which was used with the highly efficient K599 A. rhizogenes strain to infect soybean （Glycine max L. merrill） plants. DsRed2 fluorescence was easily detected in planta for the duration of a 5-week study with negligible levels of background autofluorescence. This enabled visual selection of transformed roots and subsequent excission of non-transformed roots, pHairyRed-transformed roots nodu- lated normally when inoculated with Bradyrhizobiumjaponicum. Within the nodule, DsRed2 fluorescence was plant-spe- cific, being absent in the bacteroid-dominated nodule infected zone. To test the reliability of pHairyRed as a high-fidelity binary vector reporter system, the gene encoding the soybean Nod factor receptor, GmNFRloL, was cloned into the vector for use in a complementation study with a non-nodulating nfrloL mutant of soybean. Complementation was achieved and, without exception, DsRed2 fluorescence was detected in all hairy roots that successfully formed nodules （100%, n = 34）. We anticipate broad application of this reporter system for the further analysis of root-related events in soybean and related legumes.

关键词： Fluorescence imaging genetics molecular biology plant-microbe interactions soybean plant transformation.

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Epidemiological characteristics and genetic alterations in adult diffuse glioma in East Asianpopulations

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Cancer Biology & medicine 2022年第10期19卷 1440-1459页

作者： Zongchao mo Junyi Xin Ruichao Chai peter Y.m.Woo Danny T.m.Chan Jiguang Wang Division of Life Science and State Key Laboratory of molecular Neuroscience The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina HKUST Shenzhen-Hong Kong Collaborative Innovation Research Institute Shenzhen 518000China Department of molecular Neuropathology Beijing Neurosurgical InstituteCapital Medical UniversityBeijing 100070China Department of Neurosurgery Kwong Wah HospitalHong Kong SARChina Hong Kong Neuro-Oncology Society Hong Kong SARChina Division of Neurosurgery Department of SurgeryPrince of Wales HospitalHong Kong SARChina Department of Chemical and Biological Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong SARChina Hong Kong Center for Neurodegenerative Diseases Hong Kong Science ParkHong Kong SARChina

Understanding the racial specificities of diseases—such as adult diffuse glioma,the most common primary malignant tumor of the central nervous system—is a critical step toward precision ***,we comprehensively review studies of gliomas in East Asian populations and other ancestry groups to clarify the racial differences in terms of epidemiology and genomic ***,we observed a lower glioma incidence in East Asians than in Whites;notably,patients with glioblastoma had significantly younger ages of onset and longer overall survival than the *** genome-wide association studies of various cohorts have revealed single nucleotide polymorphisms associated with overall and subtype-specific glioma ***,only 3 risk loci—5p15.33,11q23.3,and 20q13.33—were shared between patients with East Asian and White ancestry,whereas other loci predominated only in particular *** instance,risk loci 12p11.23,15q15-21.1,and 19p13.12 were reported in East Asians,whereas risk loci 8q24.21,1p31.3,and 1q32.1 were reported in studies in White *** the somatic mutational profiles of gliomas between East Asians and non-East Asians were broadly consistent,a lower incidence of EGFR amplification in glioblastoma and a higher incidence of 1p19q-IDH-TERT triple-negative low-grade glioma were observed in East Asian *** summarizing large-scale disease surveillance,germline,and somatic genomic studies,this review reveals the unique characteristics of adult diffuse glioma among East Asians,to guide clinical management and policy design focused on patients with East Asian ancestry.

关键词： Glioma East Asian epidemiology germline somatic

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Recovery of free volume in PIm-1 membranes through alcohol vapor treatment

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Frontiers of Chemical Science and Engineering 2021年第4期15卷 872-881页

作者： Faiz Almansour monica Alberto Rupesh S.Bhavsar Xiaolei Fan peter m.Budd Patricia Gorgojo Department of Chemical Engineering and Analytical Science School of EngineeringThe University of ManchesterManchester M139PLUK Department of Chemistry School of Natural SciencesThe University of ManchesterManchester M139PLUK

Physical aging is currently a major obstacle for the commercialization of PIm-1 membranes for gas separation applications.A well-known approach to reversing physical aging effects of PIm-1 membranes at laboratory scale is soaking them in lower alcohols,such as methanol and ***,this procedure does not seem applicable at industrial level,and other strategies must be *** this work,a regeneration method with alcohol vapors(ethanol or methanol)was developed to recover permeability of aged PIm-1 membranes,in comparison with the conventional soaking-in-liquid *** gas permeability and separation performance,before and post the regeneration methods,were assessed using a binary mixture of CO_(2) and CH_(4)(1:1,v:v).Our results show that an 8-hour methanol vapor treatment was sufficient to recover the original gas permeability,reaching a CO_(2) permeability>7000 barrer.

关键词： polymer of intrinsic microporosity(PIm) PIm-1 physical aging gas separation vapor-phase regeneration

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