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Supramolecular Polymerization of Hydrogen-Bonded Trimers in Bulk and Aqueous Medium

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CCS Chemistry 2024年第6期6卷 1458-1465页

作者： Freek V.de Graaf Stef A.H.jansen Sandra M.C.Schoenmakers Bas van Genabeek Marle E.j.Vleugels Bart W.L.van den Bersselaar E.W.Meijer Ghislaine vantomme Institute for Complex Molecular Systems Laboratory of Macromolecular and Organic ChemistryEindhoven University of Technology5600 MBEindhoven School of Chemistry and RNA Institute University of New South WalesSydneyNew South Wales 2052

Synthetic molecules that form functional noncovalent assemblies in water have received much attention for their potential applications as *** this work,we introduce a novel water-compatible monomer based on the phthalhydrazide moiety that assembles into hydrogen-bonded trimeric *** bulk,the material exhibits a cylindrical nanostructure in the liquid-crystalline phase at elevated temperatures,morphologically distinct from the crystalline lamellar *** water,these molecules effectively form cylinders in a one-dimensional fashion,yielding fibrous *** formation of these supramolecular polymers follows a cooperative mechanism,as evidenced by denaturation *** trimerized pattern represents a new category of aqueous su pramolecular polymers with future prospects for functional complex molecular systems.

关键词： noncovalent chemistry supramolecular polymers hydrogen bonding cooperativity nanostructure

Small-Scale Mineralogical Heterogeneity from Variations in Phase Assemblages in the Transition Zone and D" Layer Predicted by Convection Modelling

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journal of Earth Science 2011年第2期22卷 160-168页

作者： Arie P van den Berg David A Yuen Michael H G jacobs maarten V de Hoop Earth Sciences Department Utrecht University Department of Geology and Geophysics and Minnesota Supercomputing Institute University of MinnesotaMinneapolisMN 55415USA Institut für Metallurgie TU ClausthalClausthal-ZellerfeldGermany Department of Mathematics and Center of Applied and Computational Mathematics Purdue UniversityWest LafayetteINUSA

Small-scale heterogeneity in the deep mantle is concentrated in the upper-mantle transition zone （TZ）, in the depth range 410-660 km and also at the bottom 250 km D＂ region. This encourages a more detailed investigation of the potential for seismic reflectivity imaging by modelling heterogeneous structures in mantle convection models including phase transitions of the TZ and D＂ regions. We applied finite elements with variable spacing near the boundary layers in 2-D cylindrical geometry that allow for sufficient spatial resolution. We investigated several models including an extended Boussinesq （EBA） model, focused on the D＂ region, and a compressible （ALA） model for the TZ region. The results for the D＂ region show typical lens-shaped structures of post-perovskite （PPV） embedded in the perovskite （PV） background mantle, where the thickness of the lenses, at 200-400 km, strongly depends on the Clapeyron slope of the PV-PPV transition. A second phase transition （double crossing） occurs in case the core temperature is higher than the intercept temperature Ti. Our phase-dependent rheology results in contrasting effective viscosity between PV and PPV. Our model results reveal a distinctly clear mechanical weakening of the PPV lenses with about an order of magnitude lower viscosity. The shear wave-speed distributions computed from our convection results are strongly correlated with the heterogeneous distribution of the mineral phase. Gradients in the seismic wave-speed that are the target of seismological reflectivity imaging are clearly revealed. The wave-speed results show a clear resolution of the top and bottom interfaces of the PPV lenses. Our ALA model for the TZ is based on a thermodynamical model for the magnesium end- member of an olivine-pyroxene mantle. The model predicts a much more complex distribution of mineral phases, compared to our D＂ results, in agreement with the greater number of mineral phases involved in the olivine-pyroxene phase diagram for the P

关键词： mantle convection phase transition post-perovskite mineralogical heterogeneity.

Decision support model for effects estimation and proportionality assessment for targeting in cyber operations

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Defence Technology（防务技术） 2021年第2期17卷 352-374页

作者： C.Maathuis W.Pieters j.van den Berg Delft University of Technology Jaffalaan 52628 BXDelftNetherlands TNO Military Operations Oude Waaldorperweg 632597 AKDen HaagNetherlands Netherlands Defense Academy De la Reyweg 1204818 BBBredaNetherlands Open University of the Netherlands Valkenburgerweg 1776419 ATHeerlenNetherlands

Cyber operations are relatively a new phenomenon of the last two *** that period,they have increased in number,complexity,and agility,while their design and development have been processes well kept under *** a consequence,limited data(sets)regarding these incidents are *** various academic and practitioner public communities addressed some of the key points and dilemmas that surround cyber operations(such as attack,target identification and selection,and collateral damage),still methodologies and models are needed in order to plan,execute,and assess them in a responsibly and legally compliant *** on these facts,it is the aim of this article to propose a model that i))estimates and classifies the effects of cyber operations,and ii)assesses proportionality in order to support targeting decisions in cyber *** order to do that,a multi-layered fuzzy model was designed and implemented by analysing real and virtual realistic cyber operations combined with interviews and focus groups with technical e military *** proposed model was evaluated on two cyber operations use cases in a focus group with four technical e military *** the design and the results of the evaluation are revealed in this article.

关键词： Cyber operations Cyber warfare Cyber weapons Artificial intelligence Fuzzy logic Targeting

Development of ^(18)F-labeled radiotracers for neuroreceptor imaging with positron emission tomography

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Neuroscience Bulletin 2014年第5期30卷 777-811页

作者： Peter Brust jrg van den Hoff jrg Steinbach Helmholtz-Zentrum Dresden-Rossendorf Institute of Radiopharmaceutical Cancer ResearchPermoserstrasse 15Leipzig04318Germany

Positron emission tomography （PET） is an in vivo molecular imaging tool which is widely used in nuclear medicine for early diagnosis and treatment follow-up of many brain diseases. PET uses biomolecules as probes which are labeled with radionuclides of short half-lives, synthesized prior to the imaging studies. These probes are called radiotracers. Fluorine-18 is a radionuclide routinely used in the radiolabeling of neuroreceptor ligands for PET because of its favorable half-life of 109.8 min. The delivery of such radiotracers into the brain provides images of transport, metabolic, and neurotransmission processes on the molecular level. After a short introduction into the principles of PET, this review mainly focuses on the strategy of radiotracer development bridging from basic science to biomedical application. Successful radiotracer design as described here provides molecular probes which not only are useful for imaging of human brain diseases, but also allow molecular neuroreceptor imaging studies in various small-animal models of disease, including genetically- engineered animals. Furthermore, they provide a powerful tool for in vivo pharmacology during the process of pre-clinical drug development to identify new drug targets, to investigate pathophysiology, to discover potential drug candidates, and to evaluate the pharmacokinetics and pharmacodynamics of drugs in vivo.

关键词： Alzheimer's disease autoradiography blood-brain barrier brain tumor cholinergic system kinetic modeling metabolism molecular imaging neurodegeneration positron emission tomography precursor psychiatric disorder radiotracer sigma receptor

Experimental and Numerical Investigation of the Flow in Rotating Diverging Channels

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journal of Thermal Science 2010年第2期19卷 115-119页

作者： R.A.van den Braembussche j.Prinsier A.Di Sante von Karman Institute for Fluid Dynamics Turbomachinery and Propulsion Department Waterloose steenweg presently at ALSTOM POWER Steam Turbines R&D Brown Boveri Strasse 7

This paper reports on an experimental and numerical study at low Reynolds number in order to evaluate the influence of the Coriolis forces on the flow in radial rotating channels. Operating conditions correspond to the flow in radial impellers for micro gasturbine applications. A comparison of detailed flow measurements with CFD resuits indicates that Navier Stokes solvers with standard k-ω and SST turbulence models predict the flow surprisingly well and that no extra corrections for Coriolis forces are required at these operating conditions

关键词： Coriolis forces turbulence models rotating channels boundary layers

Yes indeed,most Americans do eat GMOs every day!

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journal of Integrative Plant Biology 2014年第1期56卷 4-6页

作者： maarten j.Chrispeels University of California

While teaching a course on Crop Biotechnology at Huazhong Agricultural University （Wuhan, Hubei Province, China） this past October, I was asked by one of my students if it is true that American farmers grow genetically modified crops （GMOs） only for export, and that GMO-foods are not sold in the USA. The student implied that Americans thought that such crops were ＂good enough＂ for developing countries but not good enough for themselves.

关键词： GMOs very Yes indeed,most Americans do eat GMOs every day

Risk factors for overuse injuries in short-and long-distance running: A systematic review

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journal of Sport and Health Science 2021年第1期10卷 14-28,I0001页

作者： dennis van Poppel maarten van der Worp Anouk Slabbekoorn Sylvia S.P.van den Heuvel Marienke van Middelkoop Bart W.Koes Arianne P.Verhagen Gwendolyne G.M.Scholten-Peeters Research Group Diagnostics Avans University of Applied SciencesBreda4818 CRthe Netherlands Stichting Academie Instituut Fysiotherapie PLUS Utrecht3581 MDthe Netherlands Nederlands Paramedisch Institute Amersfoort3818 LAthe Netherlands Department of General Practice Erasmus MC Medical University CenterRotterdam3015 CEthe Netherlands Center for Muscle and joint Health University of Southern DenmarkOdense5230Denmark Discipline of Physiotherapy Graduate School of HealthUniversity of TechnologySydneyChippendale NSW 2008Australia Department of Human Movement Sciences Faculty of Behavioral and Movement SciencesVrije Universiteit AmsterdamAmsterdam1081 HVthe Netherlands

Purpose:The aim of this study was to review information about risk factors for lower extremity running injuries in both short-distance(mean running distance-20 km/week and-10 km/session)and long-distance runners(mean running distance>20 km/week and>10 km/session).Methods:Electronic databases were searched for articles published up to February *** cohort studies using multivariable analysis for the assessment of individual risk factors or risk models for the occurrence of lower extremity running injuries were *** reviewers independently selected studies for eligibility and assessed risk of bias with the Quality in Prognostic Studies *** GRADE approach was used to assess the quality of the ***:A total of 29 studies were included:17 studies focused on short-distance runners,11 studies focused on long-distance runners,and 1 study focused on both types of runners.A previous running-related injury was the strongest risk factor for an injury for long-distance runners,with moderate-quality *** injuries not attributed to running was the strongest risk factor for an injury for short-distance runners,with high-quality *** body mass index,higher age,sex(male),having no previous running experience,and lower running volume were strong risk factors,with moderate quality evidence,for short-distance ***-quality evidence was found for all risk models as predictors of runningrelated injuries among short-and long-distance ***:Several risk factors for lower extremity injuries have been identified among short-and long-distance runners,but the quality of evidence for these risk factors for running-related injuries is *** injuries seem to have a multifactorial origin both in short-and long-distance runners.

关键词： Musculoskeletal health Protective factors Running-related injury

Randomized Trial of Ciclosporin with 2-h Monitoring *** with Trough Monitoring in Liver Transplantation:DELTA Study

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journal of Clinical and Translational Hepatology 2023年第4期11卷 839-849页

作者： Bastian N.Ruijter Akin Inderson Aad Pvan den Berg Herold j.Metselaar jeroen Dubbeld maarten E.Tushuizen Robert j.Porte Wojciech Polak Danny van der Helm Marjolein van Reeven Mar Rodriguez-Girondo Bart van Hoek Department of Gastroenterology and Hepatology LUMC Transplantation CenterLeiden University Medical CenterLeidenThe Netherlands Department of Gastroenterology and Hepatology University Medical Center GroningenGroningenThe Netherlands Department of Gastroenterology and Hepatology Erasmus MC Transplant InstituteErasmus Medical CenterRotterdamThe Netherlands Department of Surgery LUMC Transplantation CenterLeiden University Medical CenterLeidenThe Netherlands Department of Surgery Section HPB Surgery and Liver TransplantationUniversity of GroningenUniversity Medical Center GroningenGroningenThe Netherlands Department of Surgery Division of HPB and Transplant SurgeryErasmus MC Transplant InstituteErasmus Medical CenterRotterdamThe Netherlands Department of Biomedical Data Sciences Leiden University Medical CenterLeidenThe Netherlands.

Background and Aims:Previous trials comparing cyclosporine and tacrolimus after liver transplantation(LT)showed conflicting *** used trough monitoring for cyclosporine(C0),leading to less accurate dosing than with 2-h monitoring(C2).Only one larger trial compared C2 with tacrolimus based on trough level(T0)after LT,with similar treated biopsy-proven acute rejection(tBPAR)and graft loss,while a smaller trial had less tBPAR with C2 compared to ***,it is still unclear which calcineurin inhibitor is preferred after *** aimed to demonstrate superior efficacy(tBPAR),tolerability,and safety of C2 or T0 after first ***:Patients after first LT were randomized to C2 or ***,patient-and graft survival,safety and tolerability were the main endpoints,with analysis by Fisher test,Kaplan-Meier survival analysis and log-rank ***:In intention-totreat analysis 84 patients on C2 and 85 on T0 were *** incidence of tBPAR C2 vs.T0 was 17.7%vs.8.4%at 3 months(p=0.104),and 21.9%vs.9.7%at 6 and 12 months(p=0.049).One-year cumulative mortality C2 vs.T0 was 15.5%vs.5.9%(p=0.049)and graft loss 23.8%vs.9.4%(p=0.015).Serum triglyceride and LDL-cholesterol was lower with T0 than with *** of diarrhea in T0 vs,C2 was 64%vs.31%(p≤0.001),with no other differences in safety and ***:In the first year after LT immunosuppression with T0 leads to less tBPAR and better patient-/re-transplant-free survival as compared to C2.

关键词： Adverse effects Ciclosporin Liver transplantation Outcome Randomized controlled trial Rejection Survival Renal function Tacrolimus

Dpen,ng the Effector Protein Toolbox for Plant- Parasitic Cyst Nematode Interactions

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Molecular Plant 2016年第11期9卷 1451-1453页

作者： Sebastian Eves-van den Akker Paul R.j. Birch Division of Plant Sciences College of Life Sciences University of Dundee Dundee DD1 5EH UK The Department of Biological Chemistry John Innes Centre Norwich Research Park Norwich NR4 7UH UK

Some biotrophic plant pathogens have the remarkable ability to alter plant developmental morphology and subceliular archi- tecture. At least three examples of this ability arose indepen- dently within the phylum Nematoda. For one such example, the cyst nematodes, plant cell manipulation is rapid and pro- found; within days the cell cycle of a single cell in the vascular cylinder is arrested at G2, the vacuole reduces in size and frag- ments.

关键词： GIANT-CELLS