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Abundance and prey capture success of Common Terns(Sterna hirundo)and Pied Kingfishers(Ceryle rudis)in relation to water clarity in south-east coastal Ghana

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Avian Research 2018年第3期9卷 226-238页

作者： lars H.Holbech Francis Gbogbo Timothy Khan Aikins Department of Animal Biology and Conservation Science University of GhanaP.O.Box LG 67LegonAccraGhana Department of Biodiversity Conservation and Management University for Development StudiesBox TL 1882Nyankpala CampusTamaleGhana

Background: Water clarity may negatively influence rate of plunge diving and prey capture success of piscivorous plunge-diving birds, and therefore has implications for their conservation in polluted urban wetlands. We studied the relationship between water clarity and the abundance and prey capture success of Pied Kingfishers(Ceryle rudis) and Common Terns(Sterna hirundo) in two polluted coastal waters of south-east Ghana—the Weija Lake and Densu Delta Ramsar ***: On each wetland, data on abundance and prey capture success of plunge-divers were collected in four spatio-temporal quadrats of 100 m × 100 m and analysed with concurrent measurements of water quality parameters using GLM regression with Pearson's correlation ***: Mean prey capture success of Pied Kingfishers(34.7 e two species responded differently to water clarity. The± 13.1%) and Common Terns(35.3 abundance of Common Terns was± 11.0%) were similar but th significantly higher in less transparent/more turbid water while that of Pied Kingfishers showed no significant relationship with turbidity and transparency. In contrast, the prey capture success of Common Terns was neither related to transparency nor turbidity, as opposed to that of Pied Kingfishers which was significantly higher in more turbid/less transparent waters. Correlations between capture success and bird abundance, as well as capture attempts were insignificant, suggesting that increased fish abundance associated with cloudy water may not necessarily promote higher abundance and capture success of foraging birds. Thus, when foraging in less transparent water, capture success may depend more on predator avoidance by fish prey than lower prey detectability of foraging ***: Within a gradient of 15–51 cm transparency studied, lower water clarity did not constrain prey capture success of Common Terns and Pied Kingfishers. Further studies on the foraging ecology of plunge-divers in coastal Ghana are however r

关键词： Coastal Ghana Common Tern Pied Kingfisher Prey capture success Water turbidity and transparency

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Hydrological Responses and Flow Pathways in an Acrisol on a Forested Hillslope with a Monsoonal Subtropical Climate

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Pedosphere 2017年第6期27卷 1037-1048页

作者： lars-Erik SORBOTTEN Jannes STOLTE WANG Yanhui Jan MULDER Norconsult AS N-1338 Sandvika(Norway) Norwegian Institute of Bioeconomy Research(NIBIO) N-1430 Aas(Norway) Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091(China) Department of Environmental Sciences Norwegian University of Life SciencesN-1432 Aas(Norway)

The nature of subsurface flow depends largely on hydraulic conductivity of the vadoze zone, permeability of the underlying bedrock, existence of soil layers differing in hydraulic properties and macropore content, soil depth, and slope *** of flow pathways on forested hillslopes is essential to understand hydrological dynamics and solute transport ***, with their argic Bt horizons, are challenging in this *** further elucidate flow pathways of water and short-term variability of soil moisture patterns in Acrisols, a field study was conducted on a forested hillslope in a sub-catchment of the Tie Shan Ping(TSP)watershed, 25 km northeast of Chongqing City, *** catchment is covered by a mixed secondary forest dominated by Masson pine(Pinus massoniana).Soil saturated hydraulic conductivity(K sat) was significantly reduced at the interface between the AB and Bt horizons(2.6 × 10^(-5) vs.1.2 × 10^(-6) m s^(-1)), which led to that the flow volume generated in the Bt horizon was of little quantitative importance compared to that in the AB *** was a marked decrease in porosity between the OA and AB horizons, with a further decrease deeper in the mineral ***, the content of soil pores > 300 μm was higher in the AB horizon(14.3%)than in the Bt horizon(6.5%).This explained the difference in soil K sat *** study showed that Bt horizon had limited water transport capability, forcing part of the infiltrated rainwater as interflow through the OA and AB ***, the topsoil responded quickly to rainfall events, causing frequent cycles of saturation and aeration of soil pores.

关键词： dye tracer hillslope hydrology hydraulic conductivity preferential flow soil pores subsurface lateral flow

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Innovation in geoprocessing for a Digital Earth

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International Journal of Digital Earth 2018年第1期11卷 3-6页

作者： Barbara Hofer Carlos Granell lars Bernard Interfaculty Department of Geoinformatics-Z_GIS University of SalzburgSalzburgAustria Geospatial Technologies Research Group(GEOTEC) Universitat Jaume ICastellón de la PlanaSpain Chair of Geoinformatics Technische Universität DresdenDresdenGermany

Online geoprocessing,the provision and the use of spatial analysis functionality on the Web,is a powerful technological approach to fully realise the vision of a Digital *** Digital Earth objectives include the integration of information across diverse domains in order to address environmental and societal challenges as well as the interactive and exploratory provision of information to a wide audience(Craglia et al.2008).

关键词： interactive Earth Web

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Combined Moho Parameters Determination Using CRUST1.0 and Vening Meinesz-Moritz Model

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Journal of Earth Science 2015年第4期26卷 607-616页

作者： Majid Abrehdary lars E.Sjberg Mohammad Bagherbandi Division of Geodesy and Satellite Positioning Royal Institute of Technology (KTH) Department of Industrial Development IT and Land ManagementUniversity of G?vle

According to Vening Meinesz-Moritz （VMM） global inverse isostatic problem, either the Moho density contrast （crust-mantle density contrast） or the Moho geometry can be estimated by solv- ing a non-linear Fredholm integral equation of the first kind. Here solutions to the two Moho parame- ters are presented by combining the global geopotential model （GOCO-03S）, topography （DTM2006） and a seismic crust model, the latter being the recent digital global crustal model （CRUST1.0） with a resolution of 1°×1°. The numerical results show that the estimated Moho density contrast varies from 21 to 637 kg/m3, with a global average of 321 kg/m^3, and the estimated Moho depth varies from 6 to 86 km with a global average of 24 km. Comparing the Moho density contrasts estimated using our least-squares method and those derived by the CRUST1.0, CRUST2.0, and PREM models shows that our estimate agrees fairly well with CRUST1.0 model and rather poor with other models. The estimated Moho depths by our least-squares method and the CRUST1.0 model agree to 4.8 km in RMS and with the GEMMA1.0 based model to 6.3 km.

关键词： CRUST1.0 density contrast isostasy Moho sediment thickness.

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A short P-wave duration is associated with incident heart failure in the elderly: a 15 years follow-up cohort study

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Journal of Geriatric Cardiology 2022年第9期19卷 643-650页

作者： Bozena Ostrowska lars Lind Elena Sciaraffia Carina Blomström-Lundqvist Department of Medical Sciences Uppsala UniversityUppsalaSweden School of Medical Science Faculty of Medi-cine and HealthÖrebro UniversityÖrebroSweden

BACKGROUND Early identification of patients at risk of congestive heart failure(HF)may alter their poor *** aim was therefore to test whether simple electrocardiographic variables,the P-wave and PR-interval,could predict incident *** The PIVUS(Prospective Investigation of the Vasculature in Uppsala Seniors)study(1016 individuals all aged 70 years,50%women)was used to identify predictors of *** with prevalent HF,QRS duration≥130 ms,atrial tachyar-rhythmias,implanted pacemaker/defibrillator,second-and third-degree atrioventricular block or delta waves at baseline were *** proportional hazard analysis was used to relate the PR interval,P-wave duration(Pdur)and amplitude(Pamp),measured in lead V1,to incident *** was performed for gender,RR-interval,beta-blocking agents,systolic blood pressure,body mass index and *** Out of 836 subjects at risk,107 subjects were diagnosed with HF during a follow-up of 15 *** the multivariate analysis,there was a strong U-shaped correlation between Pdur in lead V1 and incident HF(P=0.0001)which was significant for a Pdur<60 ms[HR=2.75;95%CI:1.87-4.06,at Pdur 40 ms]but not for prolonged *** was no significant relationship between incident HF and the PR-interval or the Pamp.A Pdur<60 ms improved discrimination by 3.7%when added to the tradi-tional risk factors including sex,RR-interval,beta-blocking agents,systolic blood pressure,BMI and smoking(P=0.048).CONCLUSIONS A short Pdur,an easily measured parameter on the ECG,may potentially be a useful marker of future HF,enabling its early detection and prevention,thus improving outcomes.

关键词： prevention incident wave

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Serum amyloid P component:a new biomarker for low sperm concentration?

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Asian Journal of Andrology 2021年第5期23卷 450-455页

作者： Annika Sonesson Johan Malm lars Rylander Aleksander Giwercman Andreas Hillarp Department of Translational Medicine Lund UniversityMalmo 20502Sweden University and Regional Laboratories Region Skane Department of Clinical Chemistry and PharmacologyMalmo 20502Sweden Department of Laboratory Medicine Division of Occupational and Environmental MedicineLund UniversityLund 22381Sweden

Serum amyloid P component(SAP)is present in seminal plasma,on spermatozoa,and in different tissues of the male reproductive tract,but its function is not *** aims of this study were to determine if the concentration of SAP in seminal plasma is associated with commonly assessed semen parameters and to investigate if SAP could be a new,indirect biomarker for these *** a cross-sectional study of 203 young volunteers,the concentration of SAP in seminal plasma was measured with a in-house developed enzyme-linked immunosorbent *** plots,Pearson’s correlation coefficients(r),and linear regression models were produced,and SAP showed a statistically significant correlation with sperm concentration(r=0.75),sperm number(r=0.68),semen volume(r=-0.19),progressive sperm motility(r=0.24),and sperm immotility(r=-0.20).When the study group was dichotomized,SAP could be used to discriminate samples with a sperm concentration

关键词： fertility reproduction seminal plasma serum amyloid P component sperm

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Role of contrast enhanced ultrasonography in the assessment of hepatic metastases:A review

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World Journal of Hepatology 2010年第1期2卷 8-15页

作者： lars Peter Skovgaard larsen Department of Radiology Aarhus University Hospital

Contrast enhanced ultrasonography(CEUS) has improved both the detection and characterization of foca liver *** is now possible to evaluate in real time the perfusion of focal liver lesions in the arterial,porta and late contrast phases,and thus to characterize focal liver lesions with high diagnostic *** a result,CEUS has taken a central diagnostic role in the evaluation of focal liver lesions that are indeterminate upon computed tomography(CT) and magnetic resonance *** combined use of second generation contrast agents and low mechanica index techniques is essential for the detection of liver metastases,and it now allows the examination of the entire liver in both the portal and late phases. Several studies have shown that using CEUS instead of conventional ultrasonography without contrast agents significantly improves sensitivity in detection of liver ***,the detection rate with CEUS seems to be similar to that of *** review describes the clinical role of CEUS in detecting liver metastases,including details about examination techniques,features of metastases observed with CEUS,and clinical results and guidelines.

关键词： Ultrasound Contrast-enhanced ultrasound Liver neoplasms Metastasis Ultrasound contrast agent

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Radio observations of the first three-months of Fermi AGN at 4.8 GHz

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Research in Astronomy and Astrophysics 2012年第2期12卷 147-157页

作者： Nicola Marchili Thomas P.Krichbaum lars Fuhrmann Anton Zensus Max-Plank-Institut fr Radioastronomie

Using the Urumqi 25 m radio telescope, sources from the first three months of the Fermi-large area telescope detected active galactic nuclei （AGN） catalog with a declination of 〉 0° were observed in 2009 at 4.8 GHz. The radio flux density ap- peared to correlate with the γ-ray intensity. Intra-day variability （IDV） observations were performed in March, April and May 2009 for 42 selected γ-ray bright blazars, and ~60% of them showed evidence of flux variability at 4.8 GHz during the IDV observations. The IDV detection rate was higher than that in previous flat-spectrum AGN samples. IDV appeared more often in the very long baseline interferometry-core dominant blazars, and the non-IDV blazars showed relatively ＂steeper＂ spectral in- dices than the IDV blazars. Pronounced inter-month variability was also found in two BL Lac objects： J0112＋2244 and J0238＋1636.

关键词： galaxies: active - quasars: general - radio continuum: galaxies -gamma-rays: observations

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Seasonal fluctuation in the secretion of the antioxidant melatonin is not associated with alterations in sperm DNA damage

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Asian Journal of Andrology 2017年第1期19卷 52-56页

作者： Gunilla Maim Trine B Haugen lars Rylander Aleksander Giwercman Molecular Reproductive Research Department of Translational Medicine Lund University Skane University Hospitar Maimo Sweden Faculty of Health Sciences Oslo and Akershus University College of Applied Sciences Oslo Norway Division of Occupational and Environmental Medicine Lund University Lund Sweden.

A high sperm DNA fragmentation index （DFI） is associated with reduced fertility. DFI is influenced by the balance between reactive oxygen species and antioxidants. A circannual variation in melatonin, an antioxidant and free radical scavenger, could thus impact semen quality and fertility. The association between the major melatonin metabolite, urine 6-sulfatoxymelatonin （aMT6s）, and DFI was analyzed in 110 Oslo men （south of the Arctic Circle） and 86 Tromsoe men （north of the Arctic Circle）. Two semen analyses, summer and winter, and four urine samples （early/late summer; early/late winter）, were analyzed. The associations between aMT6s in urine and DFI were characterized in a cross-sectional and longitudinal manner using correlation analysis and linear regression. Regardless of season and location, no significant correlations between aMT6s and DFI were observed. The correlation coefficients for associations between changes over time （early winter-early summer） in aMT6s and DFI were for the total cohort： rho = -0.08 （P = 0.322）, for the Oslo cohort： rho = -0.07 （P = 0.485）, and for the Tromsoe cohort： rho = -0.14 （P = 0.273）, respectively. Similar results were seen when comparing late winter and late summer. There was no any statistically significant correlation between changes over time in aMT6s and DFI for men with DFI below and above the median value （10%）, respectively. The seasonal variation in melatonin excretion seems not to have any impact on DFh

关键词： male infertility melatonin semen quality sperm DNA index

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Surface passivation and boundary lubrication of self-mated tetrahedral amorphous carbon asperities under extreme tribological conditions

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Friction 2014年第2期2卷 193-208页

作者： Pedro A.ROMERO lars PASTEWKA Julian VON LAUTZ Michael MOSELER Fraunhofer Institute for Mechanics of Materials IWM Wöhlerstraße 1179108 FreiburgGermany Karlsruhe Institute of Technology IAM-ZBSKaiserstraße 1276131KarlsruheGermany Freiburg Materials Research Center Stefan-Meier-Straße 2179104FreiburgGermany University of Freiburg Physics DepartmentHermann-Herder-Straße 379104 FreiburgGermany

Tetrahedral amorphous carbon coatings have the potential to significantly reduce friction and wear between sliding ***,we provide atomistic insights into the evolution of the sliding interface between naked and hydrogen-passivated ta-C sliding partners under dry and lubricated *** reactive classical atomistic simulations we show that sliding induces a sp3 to sp2 rehybridization and that the shear resistance is reduced by hydrogen-passivation and hexadecane-lubrication-despite our finding that nanoscale hexadecane layers are not always able to separate and protect ta-C counter surfaces during *** asperities deform,carbon atoms within the hexadecane lubricant bind to the ta-C sliding partners resulting in degradation of the hexadecane molecules and in increased material intermixing at the sliding *** atoms from the passivation layer and from the hexadecane chains continue to be mixed within a sp2 rich sliding interface eventually generating a tribo-layer that resembles an a-C:H type of *** separation of the sliding partners,the tribo-couple splits within the newly formed sp2 rich a-C:H mixed layer with significant material transfer across the sliding *** leaves behind a-C:H coated ta-C surfaces with dangling C bonds,linear C chains and hydrocarbon fragments.

关键词： Atomic-scale simulations DLC lubrication hexadecane passivation sliding mixed layer wear

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