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Dialkyl imidazolium acetate ionosilica as efficient and recyclable organocatalyst for cyanosilylation reactions of ketones

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Green Energy & Environment 2020年第2期5卷 130-137页

作者： Thanh Tran Duy Alysson Duarte Rodrigues Giang Vo-Thanh peter Hesemann Institut de Chimie Moléculaire et des Matériaux D'Orsay UniversitéParis-SaclayUMR 818291405 Orsay CedexFrance Institut Charles Gerhardt de Montpellier Universitéde MontpellierUMR 5253 CNRS-UM-ENSCMPlace E.Bataillon34000 MontpellierFrance

We report new heterogeneous organocatalyst based on silica hybrid supported N-heterocyclic carbene(NHC-)*** organocatalyst is formed from an imidazolium iodide based ionosilica material,followed by iodide/acetate anion *** imidazolium acetate generates the organocatalytic carbene via partial deprotonation of the imidazolium ring in *** monitored via EDX,solid state NMR and ion chromatography measurements,the iodide/acetate exchange involving the imidazolium ionosilica material took place only in small *** the fact that the exchanged material contains only a very small amount of acetate,we observed good catalytic activity and recyclability in cyanosilylation reactions of ketones with trimethylsilyl *** versatility of the catalyst was highlighted via reaction with several substrates,yielding the corresponding cyanohydrins in good *** recycling experiments,the material showed decreasing catalytic activity starting from the third reaction cycle,but high catalytic activity can be regenerated via another acetate *** work is important as it highlights the possibility to combine carbene chemistry and silica,which are antagonistic at a first *** show that imidazolium acetate based ionosilicas are therefore heterogeneous'proto-carbenes',and that there is no need to form strongly basic silica supported NHCs to obtain heterogeneous *** work therefore opens the route towards heterogeneous and re-usable NHC-organocatalysts from supported ionic liquid imidazolium acetates.

关键词： N-heterocyclic carbenes Ionosilica Heterogeneous organocatalysis Cyanosilylation Ionic liquids

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Application of naturalβ-glucans as biocompatible functional nanomaterials

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Food Science and Human Wellness 2019年第4期8卷 315-319页

作者： Xiaojie Li peter Chi Keung Cheung Food and Nutritional Sciences School of Life SciencesThe Chinese University of Hong KongHong KongChina

Naturally-occurringβ-glucans are mostly investigated for their antitumor activity and immunomodulatory *** have been widely regarded as a natural source for functional foods and ***,the physico-chemically stable and biocompatible properties ofβ-glucans are rarely explored as a coating material for nanomaterials to overcome the problems of aggregation and *** article reviews on the exploration ofβ-glucans,in particular those derived from mushrooms,as a natural coating material to modify the surface properties of bioactive substances as a relatively simple and cost-effective strategy to produce stable and biocompatible nanohybrids used for biopharmaceutical *** is envisaged that suchβ-glucan-based coating method will provide new opportunities to design biocompatible functional nanomaterials for wider clinical applications.

关键词： β-Glucans Biocompatibility Biopharmaceuticals Nanohybrids

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Endoscopic Imaging of Gonads,Sex Ratio and Temperature Dependent Sex Determination in Captive Bred Juvenile Burmese Star Tortoises Geochelone platynota

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Asian Herpetological Research 2011年第4期2卷 240-244页

作者： Gerald KUCHLING Eric GOODE peter PRASCHAG Chelonia Enterprises 154 Bagot RoadSubiacoWA 6008Australia School of Animal Biology the University of Western Australia35 Stirling HighwayCrawleyWA 6008Australia Turtle Conservancy 49 Bleecker StreetSuite 601New YorkNY 10012USA Behler Chelonian Center OjaiCaliforniaCA 93024USA Behler Chelonian Center

The possibility of temperature dependent sex determination makes it important to evaluate sex ratios in captive breeding programs of threatened tortoises. We assessed the sex ratio of juvenile Burmese Star Tortoises Geochelone platynota by direct observation of their gonads through an endoscope in the captive breeding program of the Behler Chelonian Center （BCC） in California. The gonads of small juvenile G. platynota are thin and elongate, and fixed to the dorsal part of body cavity, with ovaries appearing as transparent sheaths with some oocytes visible and testes appearing as small, transparent, thin, sausage-like structures with a net of fine blood vessels on the surface. With growth, ovaries expand and masses of pre-vitellogenic follicles appear on the surface. Testes are transparent in small juveniles and, with growth, turn pinkish-white and then yellowish, with tubuli structures visible through a thin, transparent theca containing a network of fine blood vessels. Egg incubation temperatures were not rigorously monitored, but a temperature of 28.9 ℃ produced a heavily male biased sex ratio whereas a temperature of 30 ℃ produced a balanced sex ratio. This suggests that G. platynota has temperature dependent sex determination.

关键词： Geocheloneplatynota Testudinidae incubation temperature testis ovary

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Polymorphisms in microRNA targets： a source of new molecular markers for male reproduction

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Asian Journal of Andrology 2011年第3期13卷 505-508页

作者： Jernej Ogorevc peter Dovc Tanja Kunej Department of Animal Science Biotechnical Faculty University of Liubljana Domzale 1230 Slovenia

Dear Editor, Herein we discuss the impact of microRNA （miRNA） target genetic variability in male infertility genes, which can represent a source of novel molecular-genetic markers that can be used for the diagnosis of male infertility. Male-factor infertility accounts for 30%--40% of infertility cases. The causes of spermatogenetic failure found in most cases of non-obstructive azoospermia or severe oligozoospermia still remain idiopathic.

关键词： Physical sciences Condensed matter

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Voluntary blood donation and the management of clinical transfusion in new Zealand

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中国输血杂志 2012年第10期25卷 915-916页

作者： peter Flanagan new Zealand Blood Service Auckland New zealand

new Zealand is a geographically isolated country set in the Pacific *** has a land mass of 268 000 square kilometres and comprises two main *** country is geologically unstable with significant earthquake and volcanic *** country has a population of just over 4.4 million and communities are often isolated particularly so in the mountainous South Island.

关键词：新西兰无偿献血管理输血临床陆地面积太平洋不稳定

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Circulating predictive and diagnostic biomarkers for hepatitis B virus-associated hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第37期22卷 8271-8282页

作者： Stijn Van Hees peter Michielsen Thomas Vanwolleghem Department of Gastroenterology and Hepatology Antwerp University Hospital Laboratory of Experimental Medicine and Pediatrics University of Antwerp

Chronic hepatitis B virus(HBV) infected patients have an almost 100-fold increased risk to develop hepatocellular carcinoma(HCC). HCC is the fifth most common and third most deadly cancer worldwide. Up to 50% of newly diagnosed HCC cases are attributed to HBV infection. Early detection improves survival and can be achieved through regular screening. Six-monthly abdominal ultrasound, either alone or in combination with alphafetoprotein serum levels, has been widely endorsed for this purpose. Both techniques however yield limited diagnostic accuracy, which is not improved when they are combined. Alternative circulating or histological markers to predict or diagnose HCC are therefore urgently needed. Recent advances in systems biology technologies have enabled the identification of several new putative circulating biomarkers. Although results from studies assessing combinations of these biomarkers are promising, evidence for their clinical utility remains low. In addition, most of the studies conducted so far show limitations in design. Attention must be paid for instance to different ethnicities and different etiologies when studying biomarkers for hepatocellular carcinoma. This review provides an overview on the current understandings and recent progress in the field of diagnostic and predictive circulating biomarkers for hepatocellular carcinoma in chronically infected HBV patients and discusses the future prospects.

关键词： Hepatocellular carcinoma Hepatitis B virus infection Biomarkers Predictive Diagnostic Alphafetoprotein Validation Limitations MicroR NA

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Disease monitoring strategies in inflammatory bowel diseases: What do we mean by “tight control”?

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World Journal of Gastroenterology 2019年第41期25卷 6172-6189页

作者： Lorant Gonczi Talat Bessissow peter Laszlo Lakatos First Department of Medicine Semmelweis UniversityBudapest H-1083Hungary Division of Gastroenterology McGill University Health CentreMontreal H3G 1A4QuebecCanada

In recent years,there has been a critical change in treatment paradigms in inflammatory bowel diseases(IBD)triggered by the arrival of new effective treatments aiming to prevent disease progression,bowel damage and *** insufficiency of symptomatic disease control and the well-known discordance between symptoms and objective measures of disease activity lead to the need of reviewing conventional treatment algorithms and developing new concepts of optimal therapeutic *** treat-to-target strategies,defined by the selecting therapeutic targets in inflammatory bowel disease consensus recommendation,move away from only symptomatic disease control and support targeting composite therapeutic endpoints(clinical and endoscopical remission)and timely *** data suggest that early therapy using a treat-to-target approach and an algorithmic therapy escalation using regular disease monitoring by clinical and biochemical markers(fecal calprotectin and C-reactive protein)leads to improved *** review aims to present the emerging strategies and supporting evidence in the current therapeutic paradigm of IBD including the concepts of“early intervention”,“treat-to-target”and“tight control”*** also discuss the real-word experience and applicability of these new strategies and give an overview on the future perspectives and areas in need of further research and potential improvement regarding treatment targets and(“tight”)disease monitoring strategies.

关键词： Crohn’s disease Ulcerative colitis Treat-to-target Tight control Monitorting Biomarker

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Models of plate tectonics with the Lattice Boltzmann Method

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Artificial Intelligence in Geosciences 2023年第1期4卷 47-58页

作者： peter Mora Gabriele Morra David A.Yuen Geosciences Department College of Petroleum Engineering and GeosciencesKing Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia Department of Physics University of Louisiana at LafayetteLafayetteLA70504USA Department of Applied Physics and Applied Mathematics Columbia UniversityNew YorkNY10027USA Department of Information Science and Engineering and College of Marine Geosciences Ocean University of ChinaQingdao266100China

Modern geodynamics is based on the study of a large set of models,with the variation of many parameters,whose analysis in the future will require Machine Learning to be *** introduce here for the first time how a formulation of the Lattice Boltzmann Method capable of modeling plate tectonics,with the introduction of plastic non-linear rheology,is able to reproduce the breaking of the upper boundary layer of the convecting mantle in *** simulation of the earth’s mantle and lithospheric plates is a challenging task for traditional methods of numerical solution to partial differential equations(PDE’s)due to the need to model sharp and large viscosity contrasts,temperature dependent viscosity and highly nonlinear *** rheologies such as plastic or dislocation creep are important in giving mantle convection a past *** present a thermal Lattice Boltzmann Method(LBM)as an alternative to PDE-based solutions for simulating time-dependent mantle dynamics,and demonstrate that the LBM is capable of modeling an extremely nonlinear plastic *** nonlinear rheology leads to the emergence plate tectonic like behavior and history from a two layer viscosity *** results demonstrate that the LBM offers a means to study the effect of highly nonlinear rheologies on earth and exoplanet dynamics and evolution.

关键词： Lattice Boltzmann Method Mantle convection simulation Plate tectonics simulation Nonlinear rheology Extreme plasticity

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On the Range of the Common Cycle Time in a Road Network

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Journal of Harbin Institute of Technology(new Series) 2015年第6期22卷 31-36页

作者： Ting Lu Marko Wlki peter Wagner Institute of Transportation Systems German Aerospace Center (DLR) Faculty of Maritime and Transportation Ningbo University

In a coordinated road network,the optimal common cycle time is determined by evaluating the performance of the network in the given range of cycles. Normally,this range is determined by users 'experience. And a large range of common cycle time,e. g. [30,200] is chosen,which requires long computation time. This study considers that the optimal common cycle time ranges between the minimal and maximal value of intersections' individual optimal cycle time. It is proved mathematically from the convexity condition,that the delay of the network and each individual intersection are convex functions of the cycle time according to Webster delay model. Finally,2 000 random cases for the network composed of two intersections and of eight intersections are created to underline the proposed conclusions. The results of all cases confirm the validity,and show up to 90% improvement in computation time to compare with experience range. The signal optimization tool,Synchro,is also used to validate the conclusion by 50 random cases. The results confirm reliability further.

关键词： common cycle traffic signal optimization convexity Webster model

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Algorithms for enumeration problem of linear congruence modulo m as sum of restricted partition numbers

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Frontiers of Mathematics in China 2015年第1期10卷 69-89页

作者： Tian-Xiao HE peter J. -S. SHIUE Department of Mathematics Illinois Wesleyan University Bloomington IL 61702 USA Department of Mathematical Sciences University of Nevada Las Vegas Las Vegas NV 89154-4020 USA

We consider the congruence x1＋ x2 ＋… ＋ xr - c （mod m）, wherem and r are positive integers and c ∈Zm ：= {0, 1, ..., m- 1} （m ≥ 2）. Recently,W.-S. thou, T. X. He,and peter J.-S. Shiue considered the enumerationproblems of this congruence, namely, the number of solutions with the restriction x1≤~ x2≤ ... ≤ xr, and got some properties and a neat formula ofthe solutions. Due to the lack of a simple computational method for calculating the number of the solution of the congruence, we provide an algebraic and a recursive algorithms for those numbers. The former one can also give a new and simple approach to derive some properties of solution numbers.

关键词： Congruence multiset congruence solution restricted integerpartition

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