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A Single Active Trehalose-6-P Synthase （TPS） and a Family of Putative Regulatory TPS-Like Proteins in Arabidopsis

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Molecular Plant 2010年第2期3卷 406-419页

作者： Lies Vandesteene Matthew Ramon Katrien Le Roy Patrick Van Dijck filip Rolland Laboratory of Functional Biology Plant Metabolic Signaling Group Institute of Botany and Microbiology KU Leuven Kasteelpark Arenberg 31-bus 2438 B-3001 Heverlee Belgium Department of Molecular Biology Harvard Medical School Massachusetts General Hospital Boston USA Laboratory of Molecular Plant Physiology Institute of Botany and Microbiology KU Leuven Belgium Department of Molecular Microbiology VIB Leuven Belgium Laboratory of Molecular Cell Biology Institute of Botany and Microbiology KU Leuven Belgium

Higher plants typically do not produce trehalose in large amounts, but their genome sequences reveal large families of putative trehalose metabolism enzymes. An important regulatory role in plant growth and development is also emerging for the metabolic intermediate trehalose-6-P （T6P）. Here, we present an update on Arabidopsis trehalose me- tabolism and a resource for further detailed analyses. In addition, we provide evidence that Arabidop$is encodes a single trehalose-6-P synthase （TPS） next to a family of catalytically inactive TPS-like proteins that might fulfill specific regulatory functions in actively growing tissues.

关键词： Trehalose metabolism TPS Arabidopsis.

Straight and kinked InAs nanowire growth observed in situ by transmission electron microscopy

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Nano Research 2014年第8期7卷 1188-1194页

作者： filip Lenrick Martin Ek Knut Deppert Lars Samuelson L. Reine Wallenberg nCHREM/Centre for Analysis and Synthesis Lund University Lund 22100 Sweden Division of Solid State Physics Lund University Lund 22100 Sweden

Live observations of growing nanowires using in situ transmission electron microscopy （TEM） is becoming an increasingly important tool for understanding the dynamic processes occurring during nanowire growth. Here we present observations of growing InAs nanowires, which constitute the first reported in situ growth of a In-V compound in a transmission electron microscope. Real time observations of events taking place over longer growth lengths were possible due to the high growth rates of up to I nm/s that were achieved. Straight growth （mainly in 〈111〉B directions） was observed at uniform temperature and partial pressure while intentional fluctuations in these conditions caused the nanowires to form kinks and change growth direction. The mechanisms behind the kinking are discussed in detail. In situ observations of nanowire kinking has previously only been reported for nonpolar diamond structure type materials （such as Si）, but here we present results for a polar zinc blende structure （InAs）. In this study a closed cell with electron and X-ray transparent a-SiN windows was used in a conventional high resolution transmission electron microscope, enabling high resolution imaging and compositional analysis in between the growth periods.

关键词： environmental TEM nanowires in situ InAs group III-V kinking

Clinical and economic consequences of pancreatic fistula after elective pancreatic resection

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Hepatobiliary & Pancreatic Diseases International 2013年第5期12卷 533-539页

作者： filip Ceka Bohumil Jon Zdeněk ubrt Alexander Ferko Department of Surgery Faculty of Medicine and University Hospital Hradec Králové Department of Field Surgery Military Health Science FacultyHradec KrálovéDefence University Brno

BACKGROUND:Postoperative pancreatic fistula is the main cause of morbidity after pancreatic *** study aimed to quantify the clinical and economic consequences of pancreatic fistula in a medium-volume pancreatic surgery ***:Hospital records from patients who had undergone elective pancreatic resection in our department were *** fistula was defined according to the International Study Group on Pancreatic Fistula(ISGPF).The consequences of pancreatic fistula were determined by treatment cost,hospital stay,and out-patient follow-up until the pancreatic fistula was completely *** costs of the treatment are calculated in *** cost increase index was calculated for pancreatic fistula of grades A,B,and C as multiples of the total cost for the no fistula ***:In 54 months,102 patients underwent elective pancreatic *** patients(39.2%) developed pancreatic fistula,and 54 patients(52.9%) had one or more *** median length of hospital stay for the no fistula,grades A,B,and C fistula groups was 12.5,14,20,and 59 days,*** hospital stay of patients with fistula of grades B and C was significantly longer than that of patients with no fistula(P<0.001).The median total cost of the treatment was 4952,4679,8239,and 30 820 Euros in the no fistula,grades A,B,and C fistula groups,***:The grading recommended by the ISGPF is useful for comparing the clinical severity of fistula and for analyzing the clinical and economic consequences of pancreatic *** fistula prolongs the hospital stay and increases the cost of treatment in proportion to the severity of the fistula.

关键词： pancreatic resection pancreatic fistula cost analysis

A different gut microbial community between larvae and adults of a wild bumblebee nest （Bombus pascuorum）

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Insect Science 2018年第1期25卷 66-74页

作者： Anneleen Parmentier Ivan Meeus filip Van Nieuwerburgh Dieter Deforce Peter Vandamme Guy Smagghe Laboratory of Agrozoology Department of Crop Protection Faculty of Bioscience Engineering Ghent University Laboratory of Pharmaceutical Biotechnology Faculty of Pharmaceutical Sciences Ghent University Laboratory of Microbiology Department of Biochemistryand Microbiology Faculty of Sciences Ghent University Ghent Belgium

Although the gut microbial communities in adult bumblebees and their as- sociated functionalities are widely studied, descriptive data on the larval gut microbiota are still limited. The gut microbiota of a fully sampled wild Bombus pascuorum nest has been characterized, using the multiplexed Illumina MiSeq 16S ribosomal RNA ampli- con sequencing technique. The nesters and foragers inhabiting the same nest showed the typical core bacterial sequences and only marginal differences in their characterized gut microbiota. The gut microbial communities within the adult and larval specimens differed strongly, as the typical core gut bacteria in the adult bumblebees are absent in the larval bumblebees. The bacterial communities within the larval gut are dominated by bacterial phylotypes of Enterobacteriaceae and Lactobacillaceae, supplemented with genera be- longing to Corynebacteriales and Bacillales. The function of this larval gut microbiota, being different from the adult, remains to be determined.

关键词： bumblebee gut Illumina sequencing larvae microbiota nest sample size

Colony contact contributes to the diversity of gut bacteria in bumblebees （Bombus terrestris）

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Insect Science 2017年第2期24卷 270-277页

作者： Annelies Billiet Ivan Meeus filip Van Nieuwerburgh Dieter Deforce Felix Wackers Guy Smagghe Laboratory of Agrozoology Department of Crop Protection Faculty of Bioscience Engineering Ghent University B-9000 Ghent Laboratory of Pharmaceutical Biotechnology Faculty of Pharmaceutical Sciences Ghent University B-9000 Ghent BiobestNV B-2260 Westerlo Belgium

Social bees, like honeybees and bumblebees, have a close contact with nest mates of different developmental stages and generations. This could enhance bacterial transfer between nest mates and offers opportunities for direct transfer of symbionts from one generation to the next, resulting in a stable host specific gut microbiota. Gut sym- bionts of honeybees and bumblebees have been suggested to contribute in digestion and protection against parasites and pathogens. Here we studied the impact of contact with the bumblebee colony on the colonization potential of the bacterial families （i.e., Neisseri- aceae, Orbaceae, Lactobacillaceae and Bifidobacteriaceae） occurring in the gut of adult bumblebees （Bombus terrestris）. Bacterial profiles of the gut microbiota of B. terrestris were determined based on the hypervariable V4 region of the 16S rRNA using paired-end Illumina sequencing. In our experiments, we created different groups in which we grad- ually reduced the contact with nest mates and hive material. We made 3 observations：（i） reducing the contact between the colony and the bumblebee during adult life resulted in a significant drop in the relative abundance ofLactobacillus bombicola and Lactobacillus bombi; （ii） Bifidobacteriaceae required contact with nest mates to colonize the gut of B. terrestris and a significant lower bacterial diversity was observed in bumblebees that were completely excluded from colony contact during the adult life; （iii） Snodgrassella and Gilliamella were able to colonize the gut of the adult bumblebee without any direct contact with nest mates in the adult life stage. These results indicate the impact of the colony life on the diversity of the characteristic bumblebee gut bacteria.

关键词： bacterial transfer bumblebee gut Illumina sequencing microbiota social

Bandwidth limits of luminescent solar concentrators as detectors in free-space optical communication systems

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Light(Science & Applications) 2021年第1期10卷 29-40页

作者： Mark Portnoi Paul Anthony Haigh Thomas JM acdonald filip Ambroz Ivan PParkin Izzat Darwazeh loannis Papakonstantinou Photonic Innovations Lab Department of Electronic and Electrical EngineeringUniversity College LondonLondon WC1E 7JEUK School of Engineering University of NewcastleNewcastle NE17RUUK Department of Chemistry Imperial College LondonLondon W12 OBZUK Department of Chemistry University College LondonLondon WC1H OAJUK Department of Electronic and Electrical Engineering University College LondonLondon WC1E 7JEUK

Luminescent solar concentrators(LSCs)have recently emerged as a promising receiver technology in free-space optical communications due to their inherent ability to collect light from a wide field-of-view and concentrate it into small areas,thus leading to high optical *** high-speed communication systems integrating LSCs in their detector blocks have already been demonstrated,with the majority of efforts so far being devoted to maximising the received optical power and the system's ***,LSCs may pose a severe bottleneck on the bandwidth of such communication channels due to the comparably slow timescale of the fluorescence events involved,a situation further aggravated by the inherent reabsorption in these systems,and yet,an in-depth study into such dynamic effects remains absent in the *** fill this gap,we have developed a comprehensive analytical solution that delineates the fundamental bandwidth limits of LSCs as optical detectors in arbitrary free-space optical links,and establishes their equivalence with simple RC low-pass electrical ***,we demonstrate a time-domain Monte Carlo simulation platform,an indispensable tool in the multiparameter optimisation of LSC-based receiver *** work offers vital insight into LSC system dynamic behaviour and paves the way to evaluate the technology for a wide range of applications,including visible light communications,high-speed video recording,and real-time biological imaging,to name a few.

关键词： communication integrating devoted

Hydrodynamics based transfection in normal and fibrotic rats

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World Journal of Gastroenterology 2006年第38期12卷 6149-6155页

作者： Rita Yeikilis Shunit Gal Natalia Kopeiko Melia Paizi Mark Pines filip Braet Gadi Spira Department of Anatomy and Cell Biology The Bruce Rappaport Faculty of Medicine Rappaport Family Institute for Research in the Medical Sciences Technion Haifa 31096 Israel Department of Experimental Surgery The Bruce Rappaport Faculty of Medicine Rappaport Family Institute for Research in the Medical Sciences Technion Haifa 31096 Israel Institute of Animal Sciences Agricultural Research Organization the Volcani Center Bet Dagan 50250 Israel Australian Key Centre for Microscopy and Microanalysis The University of Sydney Sydney NSW 2006 Australia

AIM： Hydrodynamics based transfection （HBT）, the injection of a large volume of naked plasmid DNA in a short time is a relatively simple, efficient and safe method for in vivo transfection of liver cells. Though used for quite some time, the mechanism of gene transfection has not yet been elucidated. METHODS： A lucJferase encoding plasmid was injected using the hydrodynamics based procedure into normal and thioacetamide-induced fibrotic Sprague Dawley rats. Scanning and transmission electron microscopy images were taken. The consequence of a dual injection of Ringer solution and luciferase pDNA was followed. Halofuginone, an anti collagen type I inhibitor was used to reduce ECM load in fibrotic rats prior to the hydrodynamic injection. RESULTS： Large endothelial gaps formed as soon as 10＇ following hydrodynamic injection; these gradually returned to normal 10 d post injection. Hydrodynamic administration of Ringer 10 or 30 m prior to moderate injection of plasmid did not result in efficient transfection suggesting that endothelial gaps by themselves are not sufficient for gene expression. Gene transfection following hydrodynamic injection in thioacetamide induced fibrotic rats was diminished coinciding with the level of fibrosis. Halofuginone, a specific collagen type I inhibitor, alleviated this effect. CONCLUSION： The hydrodynamic pressure formed following HBT results in the formation of large endothelial gaps. These gaps, though important in the transfer of DNA molecules from the blood to the space of Disse are not enough to provide the appropriate conditions for hepatocyte transfection. Hydrodynamics based injection is applicable in fibrotic rats provided that ECM load is reduced.

关键词： Gene transfection Fibrosis In vivo transfection Fibrotic Hepatic Endothelial lining Endothelium Sinusoidal Fenestrae Space of disse Extracellular matrix

Colorectal cancer screening in Europe

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World Journal of Gastroenterology 2009年第47期15卷 5907-5915页

作者： Miroslav Zavoral Stepan Suchanek filip Zavada Ladislav Dusek Jan Muzik Bohumil Seifert Premysl Fric Clinic of Medicine Central Military Hospital1st Faculty of MedicineCharles UniversityPragueCZ16902Czech Republic Institute of Biostatistics and Analyses Masaryk UniversityBrnoCZ60200Czech Republic Institute of General Medicine 1st Faculty of MedicineCharles UniversityPragueCZ12800Czech Republic

Colorectal cancer(CRC)is the second most frequent malignant disease in *** year,412 000people are diagnosed with this condition,and 207 000patients die of *** 2003,recommendations forscreening programs were issued by the Council of the European Union(EU),and these currently serve as thebasis for the preparation of European guidelines forCRC *** manner in which CRC screening iscarried out varies significantly from country to countrywithin the EU,both in terms of organization and thescreening test chosen.A screening program of onesort or another has been implemented in 19 of 27 *** most frequently applied method is testing stool for occult bleeding(fecal occult blood test,FOBT).In recent years,a screening colonoscopy hasbeen introduced,either as the only method(Poland)orthe method of choice(Germany,Czech Republic).

关键词： Colorectal cancer Europe Fecal occult blood test Screening colonoscopy Screening programs

EPR and Magnetic Susceptibility Studies of Cr^(3+) Ions in the 70TeO_2·25B_2O_3·5PbO Glass Matrix

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Journal of Materials Science & Technology 1997年第5期13卷 374-378页

作者： Peteanu M. Simon V. Muresan N. Ardelean I. filip S. Faculty of Physics Babes-Bolyai University 3400 Cluj-Napoca Romania Dept. of Physics University of Oradea 3700 Oradea Romania

By using EPR and magnetic susceptibility measurements, the Cr ion distribution in the xCr2O3.(1-x)[70TeO2·25B2O3·5PbO] glasses with 0＜x≤20 mol% was studied. EPR investigation evidencedthe presence of Cr3+ ions in agreement with the experimentally obtained atomic magnetic moment values. For concentrations x≤3 mol%, the isolated Cr3+ ions coexist with those coupledby dipole-dipole interactions. For x＞3 mol%, the Cr3+ ions participate in superexchange interactions and are predominantly antiferromagnetically coupled.

关键词： PbO Ions in the 70TeO2 Glass Matrix EPR and Magnetic Susceptibility Studies of Cr Cr