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journal of Palaeogeography 2013年第4期2卷 390-401页

作者： A.j.(Tom) van Loon Su Dechen Geological Institute Adam Mickiewicz University Institute of Geology Chinese Academy of Geological Sciences State Key Laboratory of Continental Tectonics and Dynamics

The Mesoproterozoic Wumishan Formation consists mainly of dolomites that represent diagenetically transformed limestones deposited in a shallow peritidal *** the environment was tectonically stable,the study area in the Changping District(north of the Beijing area) was affected by synsedimentary ***,the dolomites in the study area were intruded by a *** resulted in contact metamorphism of the dolomites,changing them in a halo around the intrusion into *** marble,which is exposed near Taoyukou Village,shows some levels with well-developed *** stromatolites contain structures that point at deformation when the stromatolites had not yet been lithified,and thus represent soft-sediment deformation *** stromatolites apparently built up during a time-span when repeated deformational processes affected the still unlithified sediment,from the sedimentary surface down to maximally a few *** deformed stromatolites thus represent seismites,which feature is exceptionally rarely recognizable in marble.

关键词： soft-sediment deformation stromatolites seismites Wumishan Formation Mesoproterozoic Changping District Beijing

An efficient synthesis of substituted alkyl acrylates using α-keto amides

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Chinese Chemical Letters 2008年第2期19卷 175-179页

作者： R. Baharfar M. Tajbakhsh A. Hamedaninejad S.j. Hosseini Department of Chemistry University of Mazandaran P.O. Box 453 Babolsar Iran

The addition of α-keto amides as a NH-acid to alkyl propiolates and dialkyl acetylenedicarboxylates in the presence of a catalytic amount of triphenylphosphine gives the corresponding substituted alkyl acrylates.

关键词： Alkyl propiolate Triphenylphosphine NH-acids Organophosphorus compounds

Experimental　Investigation　of　Forced　Convective　Boiling　Flow　Instabilities　in　Horizontal　Helically　Coiled　Tubes

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journal of Thermal Science 1996年第3期5卷 210-216页

作者： L. j. Guo Z. P. Feng X. j. Chen N. H. Thomas National Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an China Fluid and Surface Transport Team School of Chemical Engineering The University of Birmingham Edgbaston Birmingham UK

An experimental investigation is described for the characteristics of convective boiling flow instabilities in horizontally helically coiled tubes using a steam-water two-phase closed circulation test loop at pressure from 0.5 MPa to 3.5 MPa. Three kinds of oscillation are reported: density waves; pressure drop excursions; thermal fluctuations. We describe their dependence on main system parameters such as system pressure, mass flowrate, inlet subcooling, compressible volume and heat flux. Utilizing the experimental data together with conservation constraints, a dimensionless correlation is proposed for the occurrence of density waves.

关键词： two-phase flow forced convective boiling flow instabilities horizontal helically coiled tubes experimental investigation

Transferring Western Management Knowledge to China： Perceptions of Graduates from an American Executive MBA Program

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Frontiers of Business Research in China 2013年第1期7卷 82-105页

作者： Mahmood A. Zaidi Thomas j. Norman Carlson School of Management University of Minnesota Minneapolis MN 55455 USA College of Business Administration and Public Policy California State University--Dominguez Hills Carson CA 90747 USA

As is well-known, China＇s rapid economic growth over the past decades has been impressive and this growth has driven the demand of qualified managers and professionals by both foreign and Chinese enterprises. This paper examines perceptions of the graduates of an American Executive MBA program, who experienced the transfer of Western management knowledge through team teaching and virtual student teams. The findings show that graduates are generally satisfied with their overall educational experience and its impact on their career in terms of promotions and compensation. Furthermore, the team teaching and global virtual student teams are viewed as valuable experiences.

关键词： EMBA graduate perceptions team teaching virtual internationalstudents teams

Cytokines in the BALB/c mouse testis in various conditions

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Asian journal of Andrology 2001年第1期3卷 9-19页

作者： E.Verjnkorva M.Martikainen P.Pllnen Department of Anatomy University of Turku FIN-20520 Turku FinlandDepartment of Anatomy University of Turku FIN-20520 Turku FinlandDepartment of Anatomy and Department of Obstetrics and Gynecology University of Turku FIN-20520 Turku Finland

Aim: To investigate whether testosterone, estrogens, vasectomy, experimental cryptorchidism, varicocele or agingwould induce changes in the cytokine environment of the mouse testis. Methods: In adult male BALB/c mice,testosterone implants, estradiol benzoate, vasectomy, unilateral cryptorchidism, unilateral varicocele were adminis-tered/performed. The mice were followed up for different periods of time and were then sacrificed with testes incisedfor examination. The control mice received the vehicle or sham-operation. Results: IL-10 was present in Leydigcells of nearly every testis and IL-10 + macrophages in 39% of testes. IL-6 was found in the testes of intact adultmice, mice treated with testosterone for 70 days, cryptorchid testes and sham-operated testes. Conclusion: Resultssuggest that IL-10 might be involved in the generation of the immunologically privileged microenvironment in the testis.(Asian j Androl 2001 Mar; 3: 9-19)

关键词： testosterone vasectomy estrogens cryptorchidism abdominal testis varicocele cyokines IL-10 macrophages clonal anergy

Real-Time Measurements and Modelling on Dynamic Behaviour of SonoVue Bubbles Based on Light Scattering Technology

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Chinese Physics Letters 2008年第1期25卷 172-175页

作者：屠娟 GUANj.F. MATULA T.j. Crum L.A. 魏荣爵 Key Laboratory of Modern Acoustics (Ministry of Education) Nanjing University Nanjing 210093 Center for Industrial and Medical Ultrasound Applied Physics Laboratory University of Washington Seattle WA 98105 USA

The dynamic behaviour of SonoVue microbubbles, a new generation ultrasound contrast agent, is investigated in real time with light scattering method. Highly diluted SonoVue microbubbles are injected into a diluted gel made of xanthan gum and water. The responses of individual SonoVue bubbles to driven ultrasound pulses are measured. Both linear and nonlinear bubble oscillations are observed and the results suggest that SonoVue microbubbles can generate strong nonlinear responses. By fitting the experimental data of individual bubble responses with Sarkar＇s model, the shell coating parameter of the bubbles and dilatational viscosity is estimated to be 7.0 nm-s-Pa.

关键词： MICROBUBBLE CONTRAST AGENTS CRITICAL-ANGLE ULTRASOUND MICROSPHERES BACKSCATTER WATER

Parallel droplet microfluidics for high throughput cell encapsulation and synthetic microgel generation

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Microsystems & Nanoengineering 2018年第1期4卷 525-533页

作者： Devon M.Headen joséR.García Andrés j.García Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Petit Institute for Bioengineering and Biosciences Georgia Institute of TechnologyAtlantaGA 30332USA

Cells can be microencapsulated in synthetic hydrogel microspheres(microgels)using droplet microfluidics,but microfluidic devices with a single droplet generating geometry have limited throughput,especially as microgel diameter *** we demonstrate microencapsulation of human mesenchymal stem cells(hMSCs)in small(o100μm diameter)microgels utilizing parallel droplet generators on a two-layer elastomer device,which has 600% increased throughput ***-nozzle *** of microgel diameters were compared between products of parallel ***-nozzle configurations for two square nozzle widths,35 and 100μ*** produced on parallel nozzles were equivalent to those produced on single nozzles,with substantially the same *** of hMSCs was compared for parallel nozzle devices of each *** five micrometer wide nozzle devices could be operated at twice the cell concentration of 100μm wide nozzle devices but produced more empty microgels than predicted by a Poisson *** micrometer wide nozzle devices produced microgels as predicted by a Poisson *** of microgels did not increase with the addition of cells for either nozzle *** encapsulated on 35μm wide nozzle devices had reduced viability(~70%)and a corresponding decrease in vascular endothelial growth factor(VEGF)secretion compared to hMSCs cultured on tissue culture(TC)*** hMSCs using 100μm wide nozzle devices mitigated loss of viability and function,as measured by VEGF secretion.

关键词： droplets microencapsulation microgel multilayer parallel

Resveratrol attenuates metabolic,sperm,and testicular changes in adult Wistar rats fed a diet rich in lipids and simple carbohydrates

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Asian journal of Andrology 2019年第2期21卷 201-207页

作者： Fabiana A de Oliveira Waldemar S Costa Francisco j B Sampaio Bianca M Gregorio Urogenital Research Unit Biomedical CenterState University of Rio de JaneiroRio de Janeiro 20551-030Brazil

High-fat diets affect male reproduction and sexual ***,we evaluated the effects of prolonged resveratrol administration on the metabolic,sperm,and testicular parameters of rats fed a cafeteria *** Wistar rats were divided at weaning into control(Cv n=20)and cafeteria(CAF,n=16)*** 3 months,half of them were given daily supplementations of resveratrol(C-R,n=10;CAF-R,n=8)at a dosage of 30 mg kg-1 body mass for 2 *** were killed at 5 months of age,and blood,spermatozoa,and testes were collected for further *** were analyzed by one-way ANOVA,and P<0.05 was considered statistically *** CAF diet promoted hyperglycemia(P<0.0001),and treatment with resveratrol reversed this condition(P<0.0001).The CAF diet reduced sperm viability and motility,while resveratrol improved these parameters(F<0.05).Regarding testicular morphology,the height of the seminiferous epithelium was reduced in the CAF group compared with that of the C group(P=0.0007).Spermatogenic cell proliferation was also reduced in the CAF group compared with that of the C ***,the CAF-R showed an increase in cell proliferation rate compared with that of the untreated CAF group(P=0.0024).Although it did not modify body mass,the consumption of a CAF diet promoted hyperglycemia,adverse testicular morphology remodeling,and abnormal sperm,which were attenuated by treatment with resveratrol,thus suggesting a protective effect of this antioxidant on spermatogenesis.

关键词： cafeteria diet morphology resveratrol spermatozoa testicle

The role of forests and forest products in poverty reduction in sub-Saharan Africa in the 21st century

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Forestry Studies in China 2013年第4期15卷 357-362页

作者： j.A.SOAGA V.O.KOLADE Department of Forestry & Wildlife Management Federal University of Agriculture

This study briefly examines the role of forest in poverty reduction in sub-Saharan Africa in the 21st century despite the effect of deforestation and degradation. This sub region is rated as the second region with the highest proportion of poor people globally, i.e., 325 million people. Income in the sub region has fallen below the World Bank poverty line of $1.25 per day for developing countries. In fact 45% of the population live on less than $1 per day, with two thirds of the population living in rural areas and small-holder farmers accounting for 80% of the poor. Although about 1.6 billion people live on $1–2 per day, signifying improvement in living standards, it is incomparable to income levels in developed countries. The region is therefore characterized by hunger and starvation, diseases, illnesses and under development. In the sub region, the Gini coefficient is 0.44, indicating a high incidence of poverty. Countries worst hit by absolute poverty in the sub region are Nigeria, Mali and the Central African Republic. Consequently, there is an urgent need to improve the welfare of the population of this sub region through available natural resources, such as forests, where modern technology also still lags far behind. It is therefore recommended that forest policy in the sub region be focused on forestry initiatives that will encourage access to forest resources and in turn increase the well-being of the poor through the natural bounty of the goods and services from the forest. Furthermore, forest food consumption must be encouraged among the rural poor through appropriate agroforestry practices, along with enhanced literacy, as well as education for processing and marketing of forest products in regional markets.

关键词： povery hunger under development population natural resources ,market

Zircon SHRIMP dating of granite from Qaidamshan,NW China

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Chinese Science Bulletin 2002年第5期47卷 418-422页

作者： WU Cailai YANG jingsui j.Wooden j.G.Liou LI Haibing SHI Rending MENG Fancong H.Persing A.Meibom Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Department of Geological and Environmental Sciences Stanford UniversityStanfordCA94305USA 不详

Zircon SHRIMP dating from Qaidamshan granite shows that the granite age is 446 Ma, similar to that of eclogite in the UHP belt. We think that both granite and eclogite may be formed at different stages during tectonic evolution of this area. Together with other studies we suggested that the collision of ocean and continent plates may occur at the early Caledonian in this area, forming the eclogite, and the collision of continent and continent plates at the late Caledonian, forming the Qaidanishan granite with the zircon SHRIMP age of 446 Ma.

关键词： granite zircon SHRIMP dating Qaidamshan.