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Acta Oceanologica Sinica 1993年第4期12卷 605-615页

作者： S.D.Nio J.H.Van dern berg A.Van Gelder comparative Sedimentary Division University of Utrecht The NetherlandsGeographical Department University of Utrecht The NetherlandsComparative Sedimentary Division University of Utrecht The Netherlands

The sedimentary sequence of the upper 4 m deposits in the Huanghe Harbour Pit is as follows, 1, Distributary mouth bar deposits formed before 1964; 2. lower delta plain (tidal flat) and subaqueous delta lateral deposits formed in the period of 1964-1972; 3. deposits of crevasse splay and distributary channel near mouth, formed in the period of 1972-1974; 4. tidal flat deposits formed in the period of 1975-1984. The sequence shows superimposition of sedimentary environments parallel to coastline.

关键词： Huanghe River Delta depositional sequence

Pericytes synthesize renin

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World Journal of Nephrology 2013年第1期2卷 11-16页

作者： Alison c.berg catalina chernavvsky-Sequeira Jennifer Lindsey R Ariel Gomez Maria Luisa S Sequeira-Lopez Department of Pediatrics University of Virginia School of MedicineCharlottesvilleVA 22908United States

AIM： To investigate renin expression in pericytes dur-ing normal kidney development and after deletion of angiotensinogen, the precursor for all ***： We examined the distribution of renin ex-pressing cells by immunoshistochemistry in the intersti-tial compartment of wild type （WT） and angiotensino-gen deficient （AGT -/-） mice at different developmental stages from embryonic day 18 （E18： WT, n = 4; AGT -/-, n = 5） and at day 1 （P1： WT, n = 5; AGT -/-, n = 5）, 5 （P5： WT, n = 7; AGT -/-, n = 8）, 10 （P10： WT, n = 3; AGT -/-, n = 5）, 21 （P21： WT, n = 7; AGT -/-, n =5）, 45 （P45： WT, n = 3; AGT -/-, n = 3）, and 70 （P70： WT, n = 2; AGT -/-, n = 2） of postnatal life. We quanti-fied the number of pericytes positive for renin at all the developmental stages mentioned above and compared the results of AGT -/- mice to their WT ***： In WT mice, renal interstitial pericytes syn-thesize renin in early life supporting a lineage relation-ship with renin cells in the vasculature. The number of pericytes positive for renin per area of 0.32 mm2 （density） in WT mice was maintained from fetal life till weaning age （E18 = 4.25 ± 0.63, P1 = 3.75 ± 0.48, P5 = 3.75 ± 0.48, P10 = 4 ± 0.71, P21 = 3.8 ± 0.58） and markedly decreased in adult life （P45 = 1.2 ± 0.37, P70 = 0.8 ± 0.20）. On the other hand, in AGT -/- mice the density of pericytes expressing renin was not signifi-cantly different from WT mice at E18 and P1： E18 = 5.75 ± 0.50 vs 4.25 ± 0.63 （ P = 0.106）, P1 = 9.25 ± 3.50 vs 3.75 ± 0.48 （ P = 0.175） but significantly increased from P5 till P70： P5 = 38.25 ± 5 vs 3.75 ± 0.48 （ P = 0.0004）, P10 = 173 ± 7.50 vs 4 ± 0.70 （ P = 5.24567 × 10^-7）, P21 = 83 ± 6.70 vs 3.8 ± 0.58 （P = 2.97358 × 10^-6）, P45 = 49 ± 3.50 vs 1.2 ± 0.37 （P = 8.18274 × 10^-7） and P70 = 17.8 ± 2.30 vs 0.8 ± 0.20 （ P = 3.51151 × 10^-5）. The AGT -/- mice showed a marked increase in the number of pericytes per field studied starting from P5, reaching its peak at P10, and then a gra

关键词： Interstitium Homeostasis Angiotensino-gen Kidney Renin angiotensin system Development Angiotensin deficiency Gene deletion

Professional’s skills in assessment of perineal tears after childbirth—A systematic review

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Open Journal of Obstetrics and Gynecology 2013年第4期3卷 7-15页

作者： Ann Morris Marie berg Anna Dencker centre for Person-centred care Institute of Health and Care Sciences Sahlgrenska Academy University of Gothenburg Gothenburg Sweden

Perineal tears are one of the most common complications of vaginal births and may cause discomfort and pain long time after childbirth. Visual and digital examination of perineal tears is the most common way to assess and classify a perineal tear. Recent research indicates that many tears diagnosed are misclassified. The aim of this systematic literature review was to outline research that investigates healthcare professionals’ clinical knowledge in assessment and classification of perineal tears in connection with childbirth. Searches were performed in PubMed and cINAHL. Six studies on the topic were identified and ?used to collect data for questionnaires. An integrative review was used in the analysis. Poor knowledge in perineal anatomy and lack of training in clinical assessment and classification of perineal trauma was evident among both physicians and midwives. These findings indicate that healthcare providers lack adequate knowledge and that they make incorrect assessments and errors in classification of perineal tears. The training in assessment and classification is crucial. Midwives are in a unique position to improve the standard of care in this field since they are often the first and many times the only to assess the injury.

关键词： Perineum Injuries Perineal Tears Obstetrics/Midwifery Education clinical competence Review childbirth

The Application of Suzuki coupling Reaction on the Preparation of carbosilane Dendrimers with 4-(Naphthalen-1-yl)phenyl core

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chinese chemical Letters 2006年第3期17卷 293-295页

作者： Rui Fang GUAN chuan Jian ZHOU Sheng Yu FENG David J. berg Stephen R. STOBART School of chemistry Shandong University Ji＇nan 250100 School of Materials Science and Engineering Ji＇nan University Ji＇nan 250022 School of materials science and Engineering Shandong University Ji＇nan 250071 Department of chemistry University of Victoria P.O. 3065 Victoria B.C. Canada V8W 3P6

carbosilane dendrimers with p-bromophenyl core were synthesized by alternating Grignard and hydrosilylation reaction. And the α-naphthalenyl was connected to the core by the Suzuki coupling reaction. A new carbosilane dendrimer with big π-conjugated structure [4-（naphthalen-l-yl）phenyl core] was given. It shows Suzuki coupling reaction is an effective and powerful core-functionalization method and the satisfactory result can be obtained through prolonging the reaction time with the increase of the generation of dendrimer.

关键词： Suzuki coupling reaction core functionalization carbosilane dendrimer naphthalene.

三氟甲磺酸镱催化合成噁唑啉环取代酚(胺)及相关化合物

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化学研究与应用 2007年第5期19卷 535-538页

作者：费学宁 David J. berg 天津城建学院天津300384 University of Victoria CanadaV8W 3V6

Phenolic Oxazoline is a kind of important *** this paper,Phenolic Oxazolines and its relative compounds were synthesized by a reaction of cyanophenols with aminoalcohol or diamine under the catalyzing of Yb(OSO2cF3)*** influence factors of this reaction were studied,such as the position of substituting groups,the type of cyclization and the kinds of solvent *** structures of thesis compounds were confimed by 1H NMR、13c NMR、Ms and *** a result,a method for the synthesis of Phenolic Oxazolines with a preliminary discussion was reported.

关键词：噁唑啉镧系催化剂三氟甲磺酸镱合成

What can natural edges of gallery forests teach us about woody community performance in sharp ecotones?

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Journal of Plant Ecology 2017年第6期10卷 937-948页

作者： Gabriela Aparecida de Oliveira coelho Marcela de castro Nunes Santos Terra Hisaias de Souza Almeida Eduardo van den berg Departamento de ciências Florestais Universidade Federal de LavrasC.Postal 3037LavrasMG 37200-000Brazil Instituto de Recursos Naturais Universidade Federal de ItajubáC.Postal 50ItajubáMG 37500-903Brazil Departamento de Biologia Universidade Federal de LavrasC.Postal 3037LavrasMG 37200-000Brazil

Aims The diversity and structure of forest edges are a central issue in ***,most studies have focused on anthropogenic for-est edges,being natural ones least *** studied the com-munities of shrubs and trees in natural edges of gallery forests with the main goal of learning what are the main factors that shape the structure and diversity of these natural sharp *** We evaluated 10 gallery forest sites,allocating in each of them three 15×20 m *** plots were laid out in relatively rectilinear stretches of forest edges,respecting a minimal distance of 10 m between each *** they are permanent plots and meant to study eventual fluctuations in the forest-grasslands limits,we allocated the plots with their longest side parallel to the forest edge and covering perpendicularly 5 m of the grassland and 10 m of *** the plots we identified,mapped and measured all shrub and tree individuals with diameter at breast height(DBH)≥1 *** Findings Although many differences exist among the communities in terms of density and basal area,all of them were highly dense and had relatively low basal *** addition,both the number of individu-als and the basal area increased rapidly towards the forest *** results also revealed that the edge communities are composed mainly by small individuals that demand a great amount of *** the vertical stratification and the proportion of the functional groups are similar among the sites yet change quickly in the first 10 m of the forest ***,the floristic similarities were low among the communities mainly due to the species turnover within each ***,although the overall structure is constant in the studied edges,the low floristic similarity among them possibly indicates that the species within the same functional groups are sub-stituting each other across the *** older and seemingly stable,our results showed the gallery forest edges are quite simila

关键词： beta diversity edge effects ecotone forest-grassland transition functional groups.

Do slope orientation and sampling location determine soil biota composition?

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Frontiers in Biology 2009年第3期4卷 364-375页

作者： S.PEN-MOURATOV N.berg N.GENZER S.UKABI D.SHARGIL Y.STEINbergER The Mina&Everard Goodman Faculty of Life Sciences Bar-Ilan UniversityRamat-Gan 52900Israel

“Evolution canyon”is a typical Mediterranean-basin canyon with a summer dry stream at the bottom and large differences in vegetation cover and solar radiation between the north-facing slope(NFS)and the south-facing slope(SFS).It is known to act as an abiotic mediator influencing the community structure of soil *** aim of this study was to determine the spatial dispersion of soil microbial and free-living nematode communities in the open sites(between shrubs)in the upper(0-10 cm)soil layer at four altitudes on both *** combination of relative soil moisture availability and temperature,known to be one of the main triggers for soil biota activity,was explained by slope *** above-mentioned differences were found to significantly affect microbial biomass and cO_(2)evolution resulting in temporary stress,corresponding to higher values in metabolic quotient(qcO_(2))*** differences may represent microbial investment in energy in order to overcome stress resulting from the microclimatic differences between the two ***,the degree of substrate limitation(primary production due to the differences in plant cover)of microbial activity was explained by the difference in microbial functional *** total abundance of soil free-living nematodes was found to be 2-fold higher on the SFS than on the ***-nine genera,including 12 bacteria-feeders,5 fungifeeders,12 plant-parasites,and 10 omnivore-predators,were found at the study site,with 34 genera on the NFS and 29 on the *** generic diversity of the bacteriafeeding nematodes was higher on the SFS than on the *** study elucidates the importance of slope orientation and its effect on the structural levels of soil microbial and nematode communities.

关键词： community structure “Evolution canyon” free-living nematode sampling location slope orientation

Detection of Breaking Waves Using X-Band Pulse Radar in the Nearshore Region

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china Ocean Engineering 2013年第4期27卷 549-556页

作者： Y.c.Lin c.c.chang M.c.Lee H.c.chan J.M.Leu Department of Hydraulic and Ocean Engineering National Cheng-Kung University Department of Soil and Water conservation National Chung Hsing University Department of Hospitality Management Taiwan Shoufu University

An X-band pulsed Doppler microwave radar has been used to determine the characteristics of breaking waves. Field experiments were conducted at the Shuang-Si estuary in the north of Taiwan in the winter of 2005. Analyses on maxima radar cross section and Doppler frequency shift are done to characterize wave breaking zones. Based on observations of breaking waves, the wave breaking zones are shown to be located at water depths of 1.8 to 2.2 m in the experimental site. In general, the results indicate that a radar system has the potential to delineate the spatial variation of breaking waves clearly and that this is sufficient to achieve a measurement operation for near-shore air-sea interaction events.

关键词： radar Doppler effect wave breaking coastal zone

New method for rekindling the explosive waves in Maxwellian space plasmas

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Plasma Science and Technology 2020年第12期22卷 48-58页

作者： G c DAS Kalikadas Road Byelane HazraparaCoochbehar-736101West BengalIndia

Our interest is to study the nonlinear wave phenomena in complex plasma constituents with Maxwellian electrons and ions. The main aim is to use a new method known as the(G′/G)method to exhibit the effects of dust charge fluctuations on the evolution of nonlinear waves. The coherent features of the shock and solitary waves along with the generation of high-energy waves have been amplified through the solution of the Korteweg–de Vries–Burgers equation,and the different natures of the waves were found successfully. Results are discussed graphically with the thoughtful choice of typical plasma parameters from different space plasma environments, exactly those found in cosmic dusty plasmas laden in ionospheric auroral region,radial spokes of Saturn's rings, planetary nebulae and solar F-corona region. All conclusions are in good accordance with the actual occurrences and could be of interest to further investigations of space. Moreover, the applicability of the present method is hoped to be a great enhancement by its use as ingenious mechanism used to evaluate the soliton dynamics and Burgers shock waves.

关键词： Maxwellian complex plasma nonlinear waves soliton and shock propagation (G′/G)method space plasmas