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PEcVD OF HARD AND ELASTIc BcN cOATINGS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 15-20页

作者： R. cremer D. Kurapov c. Martinez O. Kyrylov D. Neuschutz RWTH Aachen Aachen D-52056 Germany

compounds of the B-c-N system are very promising to produce superhardcoatings with good tribological, chemical and thermal properties. consequently, BcN films wereprepared by plasma enhanced chemical vapor deposition (PEcVD). The films were deposited from gaseousmixtures of BcI_3-c_2H_4-N_2-H_2-Ar in different unipolar and bipolar pulsed glow discharges at 550deg c and analyzed with respect to composition, electronic structure and mechanical properties. Themicrostructure and composition of the BcN films were determined by scanning electron microscopy(SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and reflection electronenergy loss spectroscopy (REELS). Mechanical properties were characterized using both thetraditional Vickers method and nanoindentation. The films, that were deposited using a bipolarpulsed generator, were weak and had a sponge-like structure, whereas the films prepared using anunipolar generator were well adherent, had a hardness of more than 11GPa and very high elasticrecoveries of up to 80 percent. The elasticity properties supposedly result from the formation of afullerene-like structure.

关键词： boron carbonitride PEcVD XPS X-ray diffraction microstructure

What is the most cost-effective strategy to screen for second primary colorectal cancers in male cancer survivors in Korea?

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World Journal of Gastroenterology 2009年第25期15卷 3153-3160页

作者： Sang Min Park Sun-Young Kim craig c Earle Seung-Yong Jeong Young Ho Yun National cancer center Goyang Department of Population and International Health Harvard School of Public Health Department of Family Medicine Seoul National University HospitalSeoul National University College of Medicine Program in Health Decision Science Department of Health Policy and ManagementHarvard School of Public Health Division of Population Sciences Department of Medical OncologyDana-Farber Cancer InstituteHarvard Medical School Department of Surgery Seoul National University HospitalSeoul National University College of Medicine Division of cancer control National Cancer Center

AIM： To identify a cost-effective strategy of second primary colorectal cancer （cRc） screening for cancer survivors in Korea using a decision-analytic model. METHODS： A Markov model estimated the clinical and economic consequences of a simulated 50-year- old male cancer survivors＇ cohort, and we compared the results of eight screening strategies： no screening, fecal occult blood test （FOBT） annually, FOBT every 2 years, sigmoidoscopy every 5 years, double contrast barium enema every 5 years, and colonoscopy every 10 years （cOL10）, every 5 years （cOL5）, and every 3 years （cOL3）. We included only direct medical costs, and our main outcome measures were discounted lifetime costs, life expectancy, and incremental cost- effectiveness ratio （IcER）. RESULTS： In the base-case analysis, the non-dominat- ed strategies in cancer survivors were cOL5, and cOL3. The IcER for cOL3 in cancer survivors was $5593/life- year saved （LYS）, and did not exceed $10000/LYS in one-way sensitivity analyses. If the risk of cRc in can- cer survivors is at least two times higher than that in the general population, cOL5 had an IcER of less than $10500/LYS among both good and poor prognosis of index cancer. If the age of cancer survivors starting cRc screening was decreased to 40 years, the IcER of cOL5 was tess than $7400/LYS regardless of screening compliance. cONcLUSION： Our study suggests that more strict and frequent recommendations for colonoscopy such as cOL5 and cOL3 could be considered as economically reasonable second primary cRc screening strategies for Korean male cancer survivors.

关键词： cost-effectiveness Second primary colorectal cancer Screening cancer survivor

Acute upper gastrointestinal bleeding in operated stomach: Outcome of 105 cases

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World Journal of Gastroenterology 2005年第29期11卷 4570-4573页

作者： Vassiliki N Nikolopoulou Konstantinos c Thomopoulos George I Theocharis Vassiliki A Arvaniti constantine E Vagianos Division of Gastroenterology Department of Internal Medicine University Hospital Patras Greece Department of Surgery University Hospital Patras Greece

AIM: To compare the causes and clinical outcome of patients with acute upper gastrointestinal bleeding (AUGB) and a history of gastric surgery to those with AUGB but without a history of gastric surgery in the ***: The causes and clinical outcome were compared between 105 patients with AUGB and a history of gastric surgery, and 608 patients with AUGB but without a history of gastric ***: Patients who underwent gastric surgery in the past were older (mean age: 68.1±11.7 years vs 62.8±17.8 years, P= 0.001), and the most common cause of bleeding was marginal ulcer in 63 patients (60%). No identifiable source of bleeding could be found in 22 patients (20.9%) compared to 42/608 (6.9%) in patients without a history of gastric surgery (P = 0.003). Endoscopic hemostasis was permanently successful in 26 out of 35 patients (74.3%) with peptic ulcers and active bleeding or non-bleeding visible vessel. Nine patients (8.6%) were operated due to continuing or recurrent bleeding,compared to 23/608 (3.8%) in the group of patients without gastric surgery in the past (P= 0.028). Especially in peptic ulcer bleeding patients, emergency surgery was more common in the group of patients with gastric surgery in the past [9/73 (12.3%) vs 19/360 (5.3%), P = 0.025].Moreover surgically treated patients in the past required more blood transfusion (3.3±4.0 vs 1.5±1.7, P = 0.0001) and longer hospitalization time (8.6±4.0 vs 6.9±4.9 d,P = 0.001) than patients without a history of gastric surgery. Mortality was not different between the two groups [4/105 (3.8%) vs 19/608 (3.1%)].cONcLUSION: Upper gastrointestinal bleeding seems to be more severe in surgically treated patients than in non-operated patients.

关键词： Operated stomach Active bleeding Endoscopic hemostasis

The Mesoproterozoic to early Neoproterozoic passive margin Lajeado Group and Apiaí Gabbro, Southeastern Brazil

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Geoscience Frontiers 2016年第4期7卷 683-694页

作者： G.A.c.campanha M.S.Basei F.M.Faleiros A.P.Nutman Instituto de Geociencias da Universidade de Sao Paulo Brazil School of Earth and Environmental Sciences University of Wollongong Wollongong New South Wales 2500 Australia Beijing SHRIMP center Chinese Academy of Geological Sciences 26 Baiwzhuang Road Beijing 100037 China

The Lajeado Group in the Ribeira Belt, southeastern Brazil, corresponds to an open-sea carbonate platform, comprised of seven overlapping siliciclastic and carbonatic formations, intruded in its upper portion by the Apiai Gabbro. These rocks have a Neoproterozoic tectonometamorphic overprint related to arc magmatism and the Brasiliano collisional orogeny. Geochronological constraints are given by new U- Pb SHRIMP and LA-IcP-MS data for Lajeado Group detrital zircons and for magmatic zircons from the Apial Gabbro. The youngest detrital zircons in the Lajeado Group are 1400-1200 Ma, and constrain its maximum age of deposition to be 〈1200 Ma, whereas the 877 ~ 8 Ma age for magmatic zircons in the Apiai Gabbro give the minimum age. Detritus source areas are mainly Paleoproterozoic （2200-1800 Ma） with some Archean and Mesoproterozoic contribution （1500-1200 Ma）, with distal or tectonic stable cratonic character. The Lajeado Group should be a Stenian-Tonian carbonate platform passive margin of a continent at this time, namely the columbia/Nuna or the Rodinia. The Apial Gabbro displays similar age to other intrusive basic rocks in the Lajeado and Itaiacoca groups and represents tholeiitic MORB-like magmatism that we relate to the initial break-up of a Mesoproterozoic continent and the formation of the Brasiliano oceans.

关键词： Mesoproterozoic continent Passive margin carbonate platform Brasiliano oceans Zircon U-Pb dating

Mechanical and natural ventilation systems in a greenhouse designed using computational fluid dynamics

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International Journal of Agricultural and Biological Engineering 2014年第1期7卷 1-16页

作者： Jorge Flores-Velazquez Juan I.Montero Esteban J.Baeza Juan c.Lopez Mexican Institute of Water Technology.Paseo cuauhnáhuac 8532 Col.ProgresoC.P.62550JiutepecMor.Mexico Institut de Recerca i Tecnologia Agroalimentàries 08348Cabrils(Barcelona)Spain IFAPA centro La Mojonera(Junta de Andalucía) Camino San Nicolás 104745 La MojoneraAlmeríaSpain Fundación cajamar.Estación Experimental“Las Palmerillas”Autovía del Mediterráneo Km 416 704710El EjidoAlmeríaSpain

The aim of this study was to analyse air exchange and temperature distribution in a greenhouse with combined mechanical and natural ventilation and to design more efficient mechanical ventilation *** this purpose,a computational fluid dynamics(cFD)model of the greenhouse was *** configurations were considered:configuration 1(mechanical ventilation and closed roof ventilators),configurations 2 and 3(mechanical ventilation and roof ventilators open 30%and 100%,respectively).After validation,the cFD model was used to improve the design of the greenhouse mechanical ventilation system in each of the three configurations *** greenhouse lengths,28 m,50 m,75 m and 100 m,were used in the *** to fan ventilation only,roof ventilation improved the climate of fan-ventilated greenhouses in terms of the air exchange rate(22%)and climate uniformity because the internal air was mixed better than with mechanical ventilation *** the greenhouse length increased,more advantages were achieved with natural ventilation compared to mechanical *** most configurations,there was a strong linear correlation between temperature gradient and greenhouse *** greenhouse whose regression line had the steepest slope was the one with closed roof *** the fan capacity produced a general reduction in temperature,but the effect was less intense for the greenhouses with open roof *** to box inlet ventilators,an enlarged continuous inlet in the wall opposite the fans increased overall system performance because it eliminated backflow recirculation zones,which are prone to produce high temperatures.

关键词： greenhouse cooling fan ventilation roof ventilators combined ventilation

Phosphorus Use Efficiency of Bio-Based Fertilizers:Bioavailability and Fractionation

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Pedosphere 2016年第3期26卷 310-325页

作者： céline VANEEcKHAUTE Joery JANDA Peter A.VANROLLEGHEM Filip M.G.TAcK Erik MEERS Laboratory for Analytical and Applied Ecochemistry Faculty of Bioscience EngineeringGhent University model EAU Département de Génie Civil et de Génie des EauxFaculté des Sciences et de GénieUniversité Laval

Although to date some technologies producing bio-based phosphorus(P) fertilizers have been proposed and implemented, the efficient use of the recovered products is still limited due to legislative constraints and lack of insights in the P release with time and in the corresponding mechanisms. The aim of this work was to evaluate the fertilizer performance in terms of P release and use efficiency of recovered struvite, FePO_4-sludge, digestate, and animal manure as compared to fossil reserve-based mineral triple superphosphate(TSP). First, product physicochemical characteristics and P fractions in the context of European fertilizer legislation were assessed. Next, a controlled greenhouse experiment was set up to evaluate plant reactions as well as changes of P availability in a sandy soil with high P status and a Rheinsand soil with low P status. Soil P fractions were determined in the extracts with water, ammonium lactate and cacl_2, and in soil solution sampled with Rhizon soil moisture samplers. Based on all results, it is worth conducting long-term field trials to evaluate the P release effect of struvite and digestate as compared to animal manure and TSP on different soil types with varying P status. These products showed promise as sustainable substitutes for conventional P fertilizers and could contribute to a more efficient use of P in agriculture. A refined classification of P application standards/recommendations in terms of soil P status, soil texture, and fertilizer characteristics, next to the crop P demand, is recommended. Moreover, the additional use of Rhizon samplers for determination of direct available P, including dissolved organic P, is proposed for better understanding and categorization of different P fertilizers in environmental and fertilizer legislations.

关键词： chemical soil analysis digestate nutrient recovery Rhizon samplers struvite

cryptic species composition and genetic diversity within Bemisia tabaci complex in soybean in India revealed by mtcOI DNA sequence

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Journal of Integrative Agriculture 2015年第9期14卷 1786-1795页

作者： Prasanna H c Kanakala S Archana K Jyothsna P Varma R K Malathi V G Division of Vegetable Improvement Indian Institute of Vegetable Research Advanced centre for Plant Virology Division of Plant PathologyIndian Agricultural Research Institute Department of Plant Pathology Jawaharlal Nehru Krishi Vishwavidyalaya

Bemisia tabaci is a cryptic species complex, causing signiifcant loss on many agricultural y important crops worldwide. Knowledge on species composition and diversity within B. tabaci complex is critical for evolving sustainable pest management strategies. Here we investigate the whitelfy species complex in soybean in major soybean growing states of India. The mitochondrial cytochrome oxidase gene subunit-1 (mtcOI) based phylogenetic relationships established using Bayesian methods indicated the existence of three cryptic species namely Asia I, Asia II 1, and Asia II 7. Al the haplotypes detected in the study could be assigned to these three cryptic species fol owing the species demarcation criteria of 3.5%divergence threshold. Of these, Asia II 1 was found to be predominant with wide spread distribution across the surveyed regions from cool temperate zones to hot and humid tropical plains. On the contrary, cryptic species Asia II 7 showed localized distribu-tion. The Asia II 1 exhibited the highest haplotype diversity and Asia I showed high level of nucleotide diversity. There was a signiifcantly high genetic differentiation among these three cryptic species. The MEAM 1, a dreadful invasive species was not detected in the specimens tested in the current study. The diversity and distribution of three cryptic species is discussed in the light of current knowledge on distribution of whitelfy species in India and yel ow mosaic disease observed during sampling survey.

关键词： whitefly mitochondrial cytochrome oxidase gene subunit-1 AsiaⅠ AsiaⅡ 1 AsiaⅡ 7 begomovirus and yellow mosaic disease

Influence of Fe Addition on Products of Self-Propagating High-Temperature Synthesis Reaction in 3Ti-Si-2c System

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稀有金属材料与工程 2009年第A3期38卷 113-118页

作者： Guan Q L Wang H Y Li S L Si W P Jiang Q c Key Laboratory of Automobile Materials of Ministry of Education Jilin University Changchun 130025 China

Influence of Fe addition on products of self-propagating high-temperature synthesis (SHS) reaction in 3Ti-Si-2c system was investigated in the present study. Without Fe addition, Ti5Si3 and Tic are the dominant phases along with a small amount of Ti3Sic2 phase and unreacted c left in the final products. As Fe content ranges from 10% to 30%, the products consist of Tic, Ti5Si3, Fe2Ti and unreacted c, but no trace of Ti3Sic2 phase is detected. Furthermore, the amounts of both Fe2Ti and c phases increase with Fe content increasing. Addition of Fe has a great effect on the reaction route and significantly restrains the formation of Ti3Sic2 during the combustion synthesis process, and therefore, the SHS is not an effective fabrication technique to synthesize the ternary Ti3Sic2 ceramic in either 3Ti-Si-2c or Fe-3Ti-Si-2c system. Besides, without Fe addition, Ti5Si3 presents as the coarse irregular appearance with an obviously sintered morphology. In contrast, the shape of Ti5Si3 exhibits more and more spherical (cobblestone-like) and the surface becomes increasingly smooth, because the amount of liquids formed during the SHS reaction increases with the increase of Fe content. On the other hand, with Fe content increasing from 0 to 30 wt.%, the particulate size of Tic decreases from more than 5 μm to 1 μm or less, mainly due to the fact that the combustion temperature decreases with the increase of Fe content in the preforms.

关键词：复合材料铁含量燃烧过程物理性能

In vivo radiometric analysis of glucose uptake and distribution in mouse bone

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Bone Research 2016年第1期4卷 31-38页

作者： Meredith L Zoch Diane S Abou Thomas L clemens Daniel LJ Thorek Ryan c Riddle Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Baltimore USA Division of Nuclear Medicine an Molecular Imaging Department of Radiology and Radiological Science Johns Hopkins University School of Medicine Baltimore USA Baltimore Veterans Administration Medical center Baltimore USA Department of Oncology Cancer Molecular and Functional Imaging Program Sidney Kimmel Comprehensive Cancer Center Johns Hopkins University School of Medicine Baltimore USA

Bone formation and remodeling occurs throughout life and requires the sustained activity of osteoblasts and osteoclasts, particularly during periods of rapid bone growth. Despite increasing evidence linking bone cell activity to global energy homeostasis, little is known about the relative energy requirements or substrate utilization of bone cells. In these studies, we measured the uptake and distribution of glucose in the skeleton in vivo using positron-emitting 18F-fluorodeoxyglucose （[lSF]-FDG） and non-invasive, high-resolution positron emission tomography/computed tomography （PE~/cT） imaging and ex vivo autoradiography. Assessment of [~SF]-FDG uptake demonstrated that relative to other tissues bone accumulated a significant fraction of the total dose of the glucose analog..Skeletal accumulation was greatest in young mice undergoing the rapid bone formation that characterizes early development. PET/cT imaging revealed that [lSF]-FDG uptake was greatest in the epiphyseal and metaphyseal regions of long bones, which accords with the increased osteoblast numbers and activity at this skeletal site. Insulin administration significantly increased skeletal accumulation of [lSF]-FDG, while uptake was reduced in mice lacking the insulin receptor specifically in osteoblasts or fed a high-fat diet. Our results indicated that the skeleton is a site of significant glucose uptake and that its consumption by bone cells is subject to regulation by insulin and disturbances in whole-body metabolism.

关键词： bone FDG