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Particuology 2008年第6期6卷 455-466页

作者： Feras Y. Fraige paul A. Langston Andrew j. Matchett john Dodds Faculty of Mining and Environmental Engineering Al-Hussein Bin Talal University Jordan Chemical and Environmental Engineering Nottingham University University Park Chemical Engineering University of Teesside Centre RAPSODEE Ecole Des Mines

A two-dimensional discrete element model （DEM） simulation of cohesive polygonal particles has been developed to assess the benefit of point source vibration to induce flow in wedge-shaped hoppers. The particle-particle interaction model used is based on a multi-contact principle. The first part of the study investigated particle discharge under gravity without vibration to determine the critical orifice size （Bc） to just sustain flow as a function of particle shape. It is shown that polygonal-shaped particles need a larger orifice than circular particles. It is also shown that Bc decreases as the number of particle vertices increases. Addition of circular particles promotes flow of polygons in a linear manner. The second part of the study showed that vibration could enhance flow, effectively reducing Bc. The model demonstrated the importance of vibrator location （height）, consistent with previous continuum model results, and vibration amplitude in enhancing flow.

关键词： Bulk solids Vibration DEM Hoppers Materials handling Polygon

Stress, hippocampal neurogenesis and cognition： functional correlations

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Frontiers in Biology 2016年第3期11卷 182-192页

作者： paul j. Lucassen Charlotte A. Oomen Centre for Neuroscienee Swammerdam Institute for Life Sciences University of Amsterdam Science Park 904 1098 XH Amsterdam The Netherlands Department of Molecular and Cellular Neurobiology Center for Neurogenomics and Cognitive ResearchNeuroscience Campus Amsterdam VU University Amsterdam De Boelelaan 1085 1081 HV Amsterdam The Netherlands

The brain of many species including humans, harbors stem cells that continue to generate new neurons up into adulthood. This form of structural plasticity occurs in a limited number of brain regions, i.e. the subventricular zone and the hippocampal dentate gyrus and is regulated by environmental and hormonal factors. In this minireview, we provide an overview of the effects of stress and glucocorticoid hormones on adult hippocampal neurogenesis and discuss how these effects may be relevant for cognitive function and possibly, brain disease. While its exact functional role remains elusive, adult neurogenesis has been implicated in learning and memory, fear and mood regulation and recently, adult-born neurons were found to be involved in specific cognitive functions such as pattern separation （i.e. the ability to form unique memory representations） and cognitive flexibility. The process of adult neurogenesis is influenced by several factors; whereas e.g. exercise stimulates, exposure to stress and stress hormones generally inhibit neurogenesis. Effects of acute, mild stress are generally short-lasting and recover quickly, but chronic or severe forms of stress can induce lasting reductions in adult neurogenesis. Some of the inhibitory effects of stress can be rescued by exercise, by allowing a period of recovery from stress, by drugs that target the stress system, or by some, but not all, antidepressants. Stress may, partly through its effects on adult neurogenesis, alter structure and plasticity of the hippocampal circuit. This can lead to subsequent changes in stress responsivity and aspects of memory processing, which may be particularly relevant for stress related psychopathology or brain diseases that involve perturbed memory processing.

关键词： adult neurogenesis stem cells hippocampus stress memory pattern separation cognition

Measurement of in-plane deformations of microsystems by digital holography and speckle interferometry(Invited Paper)

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Chinese Optics Letters 2009年第12期7卷 1109-1112页

作者： G. Pedrini j. Gaspar O. paul W. Osten Institut fr Technische Optik Universitt Stuttgart Department of Microsystems Engineering-IMTEK Universitt Freiburg

The reliability of microsystems is an important issue and for their quality inspection, it is necessary to know the displacements or deformations due to the applied mechanical, thermal, or electrostatic loads. We show how interferometrical techniques like digital holography and speckle interferometry can be used for the measurement of in plane deformations of microsystems with nanometric accuracy and we give a description of the measurement uncertainties.

关键词： Invited Paper Measurement of in-plane deformations of microsystems by digital holography and speckle interferometry

How Do Sugars Regulate Plant Growth and Development？ New Insight into the Role of Treha Iose-6-Phosphate

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Molecular Plant 2013年第2期6卷 261-274页

作者： Liam E. O'Hara Matthew j. paul Astrid Wingler Genetics Evolution and Environment University College London Gower Street London WCl E 6BT UK Plant Science Rothamsted Research Harpenden Hertfordshire AL5 2JQ UK

Plant growth and development are tightly controlled in response to environmental conditions that influence the availability of photosynthetic carbon in the form of sucrose. Trehalose-6-phosphate （T6P）, the precursor of trehalose in the biosynthetic pathway, is an important signaling metabolite that is involved in the regulation of plant growth and development in response to carbon availability. In addition to the plant＇s own pathway for trehalose synthesis, formation of T6P or trehalose by pathogens can result in the reprogramming of plant metabolism and development. Developmental processes that are regulated by T6P range from embryo development to leaf senescence. Some of these processes are regulated in interaction with phytohormones, such as auxin. A key interacting factor of T6P signaling in response to the environment is the protein kinase sucrose non-fermenting related kinase-1 （SnRK1）, whose catalytic activity is inhibited by T6R SnRK1 is most likely involved in the adjustment of metabolism and growth in response to starvation. The transcription factor bZlP11 has recently been identified as a new player in the T6P/SnRK1 regulatory pathway. By inhibiting SnRK1, T6P promotes biosynthetic reactions. This regulation has important consequences for crop production, for example, in the developing wheat grain and during the growth of potato tubers.

关键词： bZlP11 carbon availability plant development starvation sucrose non-fermenting related kinase-1 (SnRK1) trehalose trehalose-6-phosphate.

Forkhead box protein P1, a key player in neuronal development?

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Neural Regeneration Research 2018年第5期13卷 801-802页

作者： Luca Braccioli Cora H.Nijboer paul j.Coffer Laboratory of Neuroimmunology and Developmental Origins of Disease (NIDOD) University Medical Center Utrecht University Regenerative Medicine Center University Medical Center Utrecht Utrecht University Center for Molecular Medicine and Division of Pediatrics University Medical Center Utrecht Utrecht University

Forkhead box protein P1（FOXP1）is a transcription factor belonging to the forkhead box（FOX）proteins,a family of transcriptional regulators sharing a highly conserved forkhead DNA-binding domain（Bacon and Rappold,2012）.Previous reports have proposed a role for FOXP1 in functionally regulating the central nervous system（CNS）,while mutations in FOXP1 have been implicated in cognitive abnormalities（Bacon and Rappold, 2012）.

关键词： a key player in neuronal development Forkhead box protein P1

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Eye and Vision 2019年第1期6卷 322-330页

作者： Ke Cao Srujana Sahebjada Andrea j.Richardson paul N.Baird Centre for Eye Research Australia Royal Victorian Eye and Ear HospitalMelbourneAustralia. Department of Surgery OphthalmologyThe University of Melbourne32 Gisborne StreetEast MelbourneVIC 3000Australia

Background:Keratoconus(KC)is a common corneal condition with an unknown gender *** numerous studies have investigated the genetic component of KC,no specific genes have yet been attributed to the *** recently reported posterior segment changes occurring in the eyes of KC ***,it is not clear whether these changes are part of KC pathogenesis or reflect changes in anatomical features of the eye manifested by changes at the *** retinal changes represent the main characteristics observed in agerelated macular degeneration(AMD)and that pleiotropy has been demonstrated between different eye diseases,we wished to assess if known AMD associated genes were also associated with ***:A total of 248 KC subjects and 366 non-KC(control)subjects were recruited from public and private clinics in Melbourne for this *** single nucleotide polymorphisms(SNPs)previously associated with AMD,including rs10490924(ARMS2/HTRA1),rs10737680(CFH),rs13278062(TNFRSF10A),rs1864163(CETP),rs2230199(C3),rs3130783(IER3/DDR1),rs334353(TGFBR1),rs3812111(COL10A1),rs429608(C2/CFB),rs4420638(APOE),rs4698775(CFI),rs5749482(TIMP3),rs6795735(ADAMTS9),rs8017304(RAD51B),rs8135665(SLC16A8),rs920915(LIPC),rs943080(VEGFA),rs9542236(B3GALTL)and rs13081855(COL8A1/FILIP1L),were genotyped in this *** regression was applied to evaluate the association between these SNPs and KC on both genders together,as well as each gender *** regression was also applied to assess the association between SNPs and corneal *** correction was applied to adjust for multiple ***:Genotyping data were available for 18 *** SNP,rs6795735(ADAMTS9)was significantly associated with KC(p=3.5×10−4)when both genders were assessed,whereas rs5749482(TIMP3)was only associated in males(p=7.7×10−4)following Bonferroni multiple ***,when the covariates of age and gender were included,the associations became non-sign

关键词： Keratoconus Gender Genetic Age-related macular degeneration

Comprehensive validation of a diagnostic strategy for sequencing genes with one or multiple pseudogenes using pseudoxanthoma elasticum as a model

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journal of Genetics and Genomics 2021年第4期48卷 289-299页

作者： Wouter Steyaert Shana Verschuere paul j.Coucke Olivier M.Vanakker Center for Medical Genetics Ghent University HospitalGhentBelgium bDepartment of Biomolecular Medicine Ghent UniversityGhentBelgium Department of Human Genetics Radboud Institute for Molecular Life SciencesRadboud University Medical CenterNijmegenthe Netherlands

Pseudogenes are frequently encountered noncoding sequences with a high sequence similarity to their protein-coding *** this reason,their presence is often considered troublesome in molecular *** pseudoxanthoma elasticum(PXE),a disease predominantly caused by mutations in ATPbinding cassette family C member 6(ABCC6),the presence of two pseudogenes complicates the analysis of sequence *** whole-exome sequencing(WES)becoming the standard of care in molecular diagnostics,we wanted to evaluate whether this technique is as reliable as gene-specific targeted enrichment analysis for the analysis of *** established a PCR-based targeted enrichment and next-generation sequencing testing approach and demonstrated that the ABCC6-specific enrichment combined with the applied mapping algorithm overcomes the complication of ABCC6 pseudogene aspecificities,contrary to *** propose a time-and cost-efficient diagnostic strategy for comprehensive and accurate molecular genetic testing of PXE,which is highly automatable.

关键词： Pseudoxanthoma elasticum ABCC6 Pseudogenes Next-generation sequencing Whole-exome sequencing Targeted enrichment

Observation of a single protein by ultrafast X-ray diffraction

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Light(Science & Applications) 2024年第1期13卷 80-90页

作者： Tomas Ekeberg Dameli Assalauova johan Bielecki Rebecca Boll Benedikt j.Daurer Lutz A.Eichacker Linda E.Franken Davide E.Galli Luca Gelisio Lars Gumprecht Laura H.Gunn janos Hajdu Robert Hartmann Dirk Hasse Alexandr Ignatenko jayanath Koliyadu Olena Kulyk Ruslan Kurta Markus Kuster Wolfgang Lugmayr jannik Lübke Adrian P.Mancuso Tommaso Mazza Carl Nettelblad Yevheniy Ovcharenko Daniel E.Rivas Max Rose Amit K.Samanta Philipp Schmidt Egor Sobolev Nicusor Timneanu Sergey Usenko Daniel Westphal Tamme Wollweber Lena Worbs paul Lourdu Xavier Hazem Yousef Kartik Ayyer Henry N.Chapman jonas A.Sellberg Carolin Seuring Ivan A.Vartanyants jochen Küpper Michael Meyer Filipe R.N.C.Maia Laboratory of Molecular Biophysics Department of Cell and Molecular BiologyUppsala UniversityHusargatan 3(Box 596)SE-75124 UppsalaSweden Deutsches Electronen-Synchrotron DESY Notkestrasse 8522607 HamburgGermany European XFEL Holzkoppel 422869 SchenefeldGermany Diamond Light Source Harwell Science&Innovation CampusDidcot OX110DEUK University of Stavanger Centre Organelle ResearchRichard-Johnsensgate 44021 StavangerNorway Leibniz Institute for Experimental Virology(HPI) Centre for Structural Systems BiologyNotkestraße 8522607 HamburgGermany Dipartimento di Fisica“Aldo Pontremoli” Universitàdegli Studi di Milanovia Celoria 1620133 MilanoItaly Center for Free-Electron Laser Science DESY22607 HamburgGermany Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthacaNY 14853USA PNSensor GmbH Otto-Hahn-Ring 6D-81739 MünchenGermany Biomedical and X-Ray Physics Department of Applied PhysicsAlbaNova University CenterKTH Royal Institute of TechnologySE-10691 StockholmSweden ELI Beamlines/IoP Institute of Physics AS CR v.v.i.Na Slovance 218221 Prague 8Czech Republic Multi-User CryoEM Facility Centre for Structural Systems BiologyNotkestr.8522607 HamburgGermany University Medical Center Hamburg-Eppendorf(UKE) Martinistrasse 5220246 HamburgGermany The Hamburg Center for Ultrafast Imaging Universität HamburgLuruper Chaussee 14922761 HamburgGermany Department of Physics Universität HamburgLuruper Chaussee 14922761 HamburgGermany Department of Chemistry and Physics La Trobe Institute for Molecular ScienceLa Trobe UniversityMelbourneVIC 3086Australia Division of Scientific Computing Science for Life LaboratoryDepartment of Information TechnologyUppsala UniversityBox 337SE-75105 UppsalaSweden European Molecular Biology Laboratory c/o DESYNotkestrasse 8522607 HamburgGermany Department of Physics and Astronomy Uppsala UniversityBox 516SE-75120 UppsalaSweden Max Planck Institute for the Structure and Dynamics of Matter Luruper Chaussee 14922761 HamburgGe

The idea of using ultrashort X-ray pulses to obtain images of single proteins frozen in time has fascinated and inspired *** was one of the arguments for building X-ray free-electron *** to theory,the extremely intense pulses provide sufficient signal to dispense with using crystals as an amplifier,and the ultrashort pulse duration permits capturing the diffraction data before the sample inevitably *** was first demonstrated on biological samples a decade ago on the giant *** then,a large collaboration has been pushing the limit of the smallest sample that can be *** ability to capture snapshots on the timescale of atomic vibrations,while keeping the sample at room temperature,may allow probing the entire conformational phase space of *** we show the first observation of an X-ray diffraction pattern from a single protein,that of Escherichia coli GroEL which at 14 nm in diameter is the smallest biological sample ever imaged by X-rays,and demonstrate that the concept of diffraction before destruction extends to single *** the pattern,it is possible to determine the approximate orientation of the *** experiment demonstrates the feasibility of ultrafast imaging of single proteins,opening the way to single-molecule time-resolved studies on the femtosecond timescale.

关键词： smallest intense ultrafast

Ferritin acts as a target site for the snowdrop lectin （GNA） in the midgut of the cotton leafworm Spodoptera littoralis

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Insect Science 2008年第6期15卷 513-519页

作者： Amin Sadeghi Guy Smagghe paul Proost Els j.M. Van Damme Laboratory of Agrozoology Department of Crop Protection Laboratory of Biochemistry and Glycobiology Department of Molecular Biotechnology Faculty of Bioscience Engineering Ghent University Ghent Rega Institute Laboratory of Molecular Immunology Kathofieke Universiteit Leuven Minderbroedersstraat 10 B-3000 Leuven Belgium

The snowdrop lectin GNA （Galanthus nivalis agglutinin） has been shown to possess insecticidal activity to a range of economically important insect pests. However, the precise mechanism of insecticidal action of GNA against insects remains unknown. In this investigation, we attempted to purify and identify receptor（s） responsible for binding of GNA in the larval midgut of a major lepidopteran pest （the cotton leafworm, Spodoptera littoralis） to better understand its mode of action. Therefore, cytoplasmic as well as membrane proteins from 800 larval midguts were chromatographed on a column with immobilized GNA. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the proteins eluted from the GNA column followed by sequencing of the GNA-binding proteins and BLAST analyses revealed that the N-terminal sequences of a 24 kDa polypeptide purified from the cytoplasmic and membrane protein fraction revealed sequence similarity to sequences encoding heavy chain homologs of ferritin from Manduca sexta （76% sequence identity）, Calpodes ethlius （80% sequence identity） and Bombyx mori （61% sequence identity）. Furthermore, the N-terminal sequence of a 31 kDa polypeptide from the membrane protein fraction showed sequence similarity to a light chain homolog of ferritin from Manduca sexta （88% sequence identity）.

关键词： ferritin Galanthus nivalis agglutinin GNA Lepidoptera midgut receptors Spodoptera littoralis