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Current therapeutic strategies for inflammation following traumatic spinal cord injury

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Neural Regeneration Research 2012年第23期7卷 1812-1821页

作者： Priyanka l.Singh Nitin Agarwal james C.Barrese Robert F.Heary Department of Neurological Surgery UMDNJ-New Jersey Medical SchoolNewarkNJ 07101-1709USA Reynolds Family Spine laboratory NewarkNJ 07101-1709USA

Damage from spinal cord injury occurs in two phases-the trauma of the initial mechanical insult and a secondary injury to nervous tissue spared by the primary *** from damage sustained as a result of direct trauma to the spinal cord,the post-traumatic inflammatory response contributes significantly to functional motor deficits exacerbated by the secondary *** the detrimental aspects of the inflammatory response is a promising strategy to potentially ameliorate the secondary injury,and promote significant functional *** review details how the inflammatory component of secondary injury to the spinal cord can be treated currently and in the foreseeable future.

关键词： acute spinal cord injury inflammation treatment secondary injury neuroprotective hypothermia erythropoietin estrogen etanercept rolipram

Vascular calcification does not predict anastomotic leak or conduit necrosis following oesophagectomy

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World Journal of Gastrointestinal Surgery 2019年第7期11卷 308-321页

作者： Benjamin J Jefferies Emily Evans james Bundred james Hodson John l Whiting Colm Forde Ewen A Griffiths College of Medical and Dental Sciences University of BirminghamBirmingham B15 2TTUnited Kingdom Department of Radiology University Hospitals Birmingham NHS Foundation TrustBirmingham B15 2WBUnited Kingdom Institute of Translational Medicine University Hospitals Birmingham NHS Foundation TrustBirmingham B15 2TTUnited Kingdom Department of Upper Gastrointestinal Surgery University Hospitals Birmingham NHS Foundation TrustBirmingham B15 2THUnited Kingdom Institute of Cancer and Genomic Sciences University of BirminghamBirmingham B15 2TTUnited Kingdom

BACKGROUND Anastomotic leaks(Al)and gastric conduit necrosis(CN)are serious complications following *** studies have suggested that vascular calcification may be associated with an increased Al rate,but this has not been validated in a United Kingdom *** To investigate whether vascular calcification identified on the pre-operative computed tomography(CT)scan is predictive of Al or *** Routine pre-operative CT scans of 414 patients who underwent oesophagectomy for malignancy with oesophagogastric anastomosis at the Queen Elizabeth Hospital Birmingham between 2006 and 2018 were retrospectively *** of the proximal aorta,distal aorta,coeliac trunk and branches of the coeliac trunk was scored by two *** relationship between these calcification scores and occurrence of Al and CN was then *** Esophagectomy Complications Consensus Group definition of Al and CN was *** Complication data were available in n=411 patients,of whom 16.7%developed either Al(15.8%)or CN(3.4%).Rates of Al were significantly higher in female patients,at 23.0%,compared to 13.9%in males(P=0.047).CN was significantly more common in females,(8.0%vs 2.2%,P=0.014),patients with diabetes(10.6%vs 2.5%,P=0.014),a history of smoking(10.3%vs 2.3%,P=0.008),and a higher American Society of Anaesthesiologists grade(P=0.024).Out of the 14 conduit necroses,only 4 occurred without a concomitant *** statistically significant association was found between calcification of any of the vessels studied and either of these *** analyses were then performed to identify whether a combination of the calcification scores could be identified that would be significantly predictive of any of the ***,the stepwise approach did not select any factors for inclusion in the final *** analysis was repeated for composite outcomes of those patients with either Al or CN(n=69,16.7%)and for those with both Al and CN(n=10,2.

关键词： Oesophagectomy Anastomotic leak Gastric conduit necrosis Calcification Computed tomography Ischaemia

Detection and Determination of the Variation of the Speed of Time

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Journal of Modern Physics 2021年第6期12卷 761-780页

作者： Robert M. l. baker Bonnie Sue baker Fangyu li Gravwave llC Playa del Rey USA Transportation Sciences Corporation Gravitational-Wave Department Playa del Rey USA Department of Physics Chongqing University Chongqing China

Steadily increasing time is involved in most scientific analyses. like other dimensions in spacetime we suggest that there can be a variation rate of time’s progress or speed of time in the time dimension. We study speed-of-time variation observational data in three processes: muon decay, galaxy rotation (related to dark matter) and the separation speed of celestial objects as our Universe progresses (related to dark energy). Each of these processes will have an “observed value” of their time of completion Po from an observation of the process at time t1 and an “expected value” Pe of that time at time t2. Their difference is attributed to the variation of the speed of time. We provide a possible explanation for the anomalous separation of the observed and the expected galactic velocity curves. Our conclusion is that it is unnecessary to introduce dark matter or dark energy.

关键词： Early Universe High-Frequency Gravitational Waves High-Frequency Relic Gravitational Waves Primordial Gravitational Waves Cosmology Speed of Time Dark Matter Dark Energy Galactic Velocity Curves

Wing, tail, and vocal contributions to the complex acoustic signals of courting Calliope hummingbirds

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Current Zoology 2011年第2期57卷 187-196页

作者： Christopher james ClARK Peabody Museum of Natural History Yale University PO Box 208106 New Haven CT 06511 USA Museum of Vertebrate Zoology University of California- Berkeley Berkeley CA USA

Multi-component signals contain multiple signal parts expressed in the same physical modality. One way to identify individual components is if they are produced by different physical mechanisms. Here, I studied the mechanisms generating acoustic signals in the courtship displays of the Calliope hummingbird Stellula calliope. Display dives consisted of three synchronized sound elements, a high-frequency tone （hfl）, a low frequency tone （lft）, and atonal sound pulses （asp）, which were then followed by a frequency-modulated fall. Manipulating any of the rectrices （tail-feathers） of wild males impaired production of the lft and asp but not the hfl or fall, which are apparently vocal. I tested the sound production capabilities of the rectrices in a wind tunnel. Single rectrices could generate the lft but not the asp, whereas multiple rectrices tested together produced sounds sitlfilar to the asp when they fluttered and collided with their neighbors percussively, representing a previously unknown mechanism of sound production. During the shuttle display, a trill is generated by the wings during pulses in which the wingbeat frequency is elevated to 95 Hz, 40% higher than the typical hovering wingbeat frequency. The Calliope hummingbird courtship displays include sounds produced by three independent mechanisms, and thus include a minimum of three acoustic signal components. These acoustic mechanisms have different constraints and thus potentially contain different messages. Producing multiple acoustic signals via multiple mechanisms may be a way to escape the constraints present in any single mechanism .

关键词： Calliope Hummingbird Courtship Multicomponent Signal Sonation Wind Tunnel

Camouflage Patterning in Maize leaves Results from a Defect in Porphobilinogen Deaminase

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Molecular Plant 2009年第4期2卷 773-789页

作者： Mingshu Huanga Thomas l. Slewinski R. Frank baker , Diane Janick-Buckner Brent Buckner Gurmukh S. Johal David M. Braun Department of Biology Pennsylvania State University University Park PA 16802 Division of Science Truman State University Kirksville MO 63501 Department of Botany and Plant Pathology Purdue University West Lafayette IN 47907

Maize leaves are produced from polarized cell divisions that result in clonal cell lineages arrayed along the long axis of the leaf. We utilized this stereotypical division pattern to identify a collection of mutants that form chloroplast pigmentation sectors that violate the clonal cell lineages. Here, we describe the camouflage1 （cfl） mutant, which develops nonclonal, yellow-green sectors in its leaves. We cloned the cfl gene by transposon tagging and determined that it encodes porphobilinogen deaminase （PBGD）, an enzyme that functions early in chlorophyll and heme biosynthesis. While PBGD has been characterized biochemically, no viable mutations in this gene have been reported in plants. To investigate the in vivo function of PBGD, we characterized the cfl mutant. Histological analyses revealed that cfl yellow sectors display the novel phenotype of bundle sheath cell-specific death. light-shift experiments determined that constant light suppressed cfl sector formation, a dark/light transition is required to induce yellow sectors, and that sectors form only during a limited time of leaf development. Biochemical experiments determined that of 1 mutant leaves have decreased PBGD activity and increased levels of the enzyme substrate in both green and yellow regions. Furthermore, the cfl yellow regions displayed a reduction in catalase activity. A threshold model is hypothesized to explain the cfl variegation and incorporates photosynthetic cell differentiation, reactive oxygen species scavenging, and PBGD function.

关键词： camouflage1 maize porphobilinogen deaminase tetrapyrrole biosynthesis variegated leaf.

A tri-layer approach to controlling nanopore formation in oxide supports

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Nano Research 2019年第6期12卷 1223-1228页

作者： Abha A.Gosavi james l.Hedrick Peng-Cheng Chen Justin M.Notestein Chad A.Mirkin Department of Chemical and Biological Engineering Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA International Institute for Nanotechnology Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA Department of Materials Science and Engineering Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA Department of Chemistry Northwestern University2145 Sheridan RoadEvanstonIllinois 60208USA

A novel tri-layer approach for immobilizing metal nanoparticles in SiO2 supports is *** this work,we show that under rapid heating to temperatures of approximately 1,000 ℃,metal nanoparticles less than 15 nm in size will entrench in the SiO2 layer on a silicon wafer to create pores as deep as 250 *** studied and characterized this entrenching behavior and subsequent nanopore formation for a wide variety of metal nanoparticles,including Au,Ag,Pt,Pd,and *** also demonstrate that an Al2O3 layer acts as a barrier to such pore ***,by creating a tri-layer architecture consisting of SiO2 on Al2O3 on silicon wafers,we can control the depth to which nanoparticles entrench between 3-5 *** small range allows one to entrench particles for the purpose of immobilization but still present them above the *** two advances of moving into the sub-15 nm size regime and of controlled particle immobilization through entrenchment have important implications in studying site-isolated and stabilized metal nanoparticles for applications in sensing,separations,and catalysis.

关键词： nanopore formation nanoparticle entrenchment nanoparticle stabilization atomic force microscopy Au nanoparticles

High resolution scanning gate microscopy measurements on InAs/GaSb nanowire Esaki diode devices

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Nano Research 2014年第6期7卷 877-887页

作者： james l. Webb Olof Perssor Kimberly A. Dick Claes Thelander Rainer Timm Anders Mikkelsen Division of Synchrotron Radiation Research Lund University Sweden Center forAnalysis and Synthesis Lund University Sweden Division of Solid State Physics Lund University Sweden

Gated transport measurements are the backbone of electrical characterization of nanoscale electronic devices. Scanning gate microscopy （SGM） is one such gating technique that adds crucial spatial information, accessing the localized properties of semiconductor devices. Nanowires represent a central device concept due to the potential to combine very different materials. However, SGM on semiconductor nanowires has been limited to a resolution in the 50-100 nm range. Here, we present a study by SGM of newly developed III-V semiconductor nanowire InAs/GaSb heterojunction Esaki tunnel diode devices under ultra-high vacuum. Sub-5 nm resolution is demonstrated at room temperature via use of quartz resonator atomic force microscopy sensors, with the capability to resolve InAs nanowire facets, the InAs/GaSb tunnel diode transition and nanoscale defects on the device. We demonstrate that such measurements can rapidly give important insight into the device properties via use of a simplified physical model, without the requirement for extensive calculation of the electrostatics of the system. Interestingly, by precise spatial correlation of the device electrical transport properties and surface structure we show the position and existence of a very abrupt （〈10 nm） electrical transition across the InAs/GaSb junction despite the change in material composition occurring only over 30-50 nm. The direct and simultaneous link between nanostructure composition and electrical properties helps set important limits for the precision in structural control needed to achieve desired device performance.

关键词： nanowire,scanning gate microscopy Esaki tunnel diode,InAs,GaSb,III-V,heterostructure

Ground-based and additional science support for SMIlE

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Earth and Planetary Physics 2024年第1期8卷 275-298页

作者： J.A.Carter M.Dunlop C.Forsyth K.Oksavik E.Donovon A.Kavanagh S.E.Milan T.Sergienko R.C.Fear D.G.Sibeck M.Connors T.Yeoman X.Tan M.G.G.T.Taylor K.McWilliams J.Gjerloev R.Barnes D.D.Billet G.Chisham A.Dimmock M.P.Freeman D.-S.Han M.D.Hartinger S.-Y.W.Hsieh Z.-J.Hu M.K.james l.Juusola K.Kauristie E.A.Kronberg M.lester J.Manuel J.Matzka I.McCrea Y.Miyoshi J.Rae l.Ren F.Sigernes E.Spanswick K.Sterne A.Steuwer T.Sun M.-T.Walach B.Walsh C.Wang J.Weygand J.Wild J.Yan J.Zhang Q.-H.Zhang Planetary Sciences Group School of Physics and AstronomyUniversity of LeicesterUniversity RoadLeicesterLE17RHUK Rutherford Appleton laboratory Space Science Technology Facilities CouncilOxfordshireUK School of Space and Environment Beihang UniversityBeijing 100191China Key laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100017China Department of Space and Climate Physics UCLMullard Space Science LaboratoryHolmbury St.MaryDorkingSurreyRH56NTUK Birkeland Centre for Space Science Department of Physics and Technology.University of BergenBergenNorway Department of Physics and Astronomy University of Calgary2500 University DriveCalgaryAlbertaCanada T2N 1N4 British Antarctic Survey CambridgeUK Swedish Institute of Space Physics KirunaSweden West Highfield Campus University of SouthamptonUniversity RoadSO171BJUK Goddard Space Flight Center NASAGreenbeltMarylandUSA Athabasca University AthabascaCanada ESTEC European Space AgencyNetherlands University of Saskatchewan SaskatoonCanada The Johns Hopkins University Applied Physics laboratory LaurelMarylandUSA Swedish Institude of Space Physics UppsalaSE 75121Sweden Tongji University Shanghai 200092China Center for Space Plasma Physics Space Science Institute4765 Walnut Street Suite BBoulderColorado80301USA Polar Research Institute of China Shanghai 200136China Finnish Meteorological Institute(FMI) Finland Department of Earth and Environmental Sciences(Geophysics) Ludwig Maximilian University of Munich(LMU)MunichTheresienstr.41MunichD-80333Germany Canadian Space Agency MontrealCanada GFZ German Research Centre for Geosciences PotsdamGermany Nagoya University Institute for Space Earth Environment ResearchCenter for Integrated Data ScienceNagoyaAichiJP 464-8601 Northumbria University Newcastle upon TyneTyne and WearUK NE18ST National Space Science Center Chinese Academy SciencesBeijing 100190China Arctic Geophysics University Centre in Svalbard

The joint European Space Agency and Chinese Academy of Sciences Solar wind Magnetosphere Ionosphere link Explorer(SMIlE)mission will explore global dynamics of the magnetosphere under varying solar wind and interplanetary magnetic field conditions,and simultaneously monitor the auroral response of the Northern Hemisphere *** these large-scale responses with medium and fine-scale measurements at a variety of cadences by additional ground-based and space-based instruments will enable a much greater scientific impact beyond the original goals of the SMIlE ***,we describe current community efforts to prepare for SMIlE,and the benefits and context various experiments that have explicitly expressed support for SMIlE can offer.A dedicated group of international scientists representing many different experiment types and geographical locations,the Ground-based and Additional Science Working Group,is facilitating these *** include constructing an online SMIlE Data Fusion Facility,the discussion of particular or special modes for experiments such as coherent and incoherent scatter radar,and the consideration of particular observing strategies and spacecraft *** anticipate growing interest and community engagement with the SMIlE mission,and we welcome novel ideas and insights from the solar-terrestrial community.

关键词： magnetosphere ionosphere magnetosphere-ionosphere coupling ground-based experimentation SMIlE conjunctions missions

Comparison of phase unwrapping algorithms for living cell's interference pattern

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Journal of Beijing Institute of Technology 2013年第4期22卷 530-535页

作者：王霞佟洁王萌 SCHMIDT Greg MOORE Duncan T. MCGRATH james l. School of Optoelectronics Beijing Institute of Technology Institute of Optics University of Rochester Biomedical Engineering University of Rochester

A multiphase microscopic interference system is designed to measure the height of cell which is important to the research of collective cell migration in physiology and medicine. This sys- tem can quantitatively measure cell height across a living monolayer without knowing the refractive index of cells. For the interference pattern, because the phases are all wrapped between - π to π, it is necessary to get the real phase through phase unwrapping,a method to restore the wrapped phase data of the object by using numerical calculations. Three representative algorithms are selected to unwrap the interference pattern of ceils： branch-cut method, quality-guided method and network method. Although each of them can restore the phase, their performances are obviously different. We compare these methods and find that branch-cut method needs the smallest execution time and can obtain good unwrapped patterns when noises are not serious.

关键词： unwrapping algorithms interference pattern cell height branch-cut quality-guided