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Hitachi m2L multimedia Recorder——制作自己的音频/视频节目

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电子与电脑 1999年第9期 13-13页

作者： laurel merlino ,唐宏

究竟应该买数码照相机还是应该买数码摄像机?两者都要！1.2磅重的Hitachi m2L multimedia Recorder可以捕获和回放静止图像以及mPEG-1格式的视频图像,这些图像(还包含了数码音频)非常适合用于即时的Web发布和发送电子邮件。 m2L的mPEG-... 详细信息

究竟应该买数码照相机还是应该买数码摄像机?两者都要！1.2磅重的Hitachi m2L multimedia Recorder可以捕获和回放静止图像以及mPEG-1格式的视频图像,这些图像(还包含了数码音频)非常适合用于即时的Web发布和发送电子邮件。 m2L的mPEG-1视频功能可以在每秒30帧的速率下提供352×240的分辨率。在JPEG模式下,静止图像的分辨率可以达到704×480,只是这些50K大小的文件看起来不太清晰。不过其声音质量绝对是一流的。令人遗憾的是,m2L的标准配置只

关键词：静止图像 Hitachi m2L multimedia Recorder 音频视频图像

Probing shock geometry via the charge to mass ratio dependence of heavy ion spectra from multiple spacecraft observations of the 2013 November 4 event

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Research in Astronomy and Astrophysics 2016年第12期16卷 101-106页

作者： Lulu Zhao Gang Li Glenn m. mason Christina Cohen Richard mewaldt mihir Desai Rob Ebert maher Al-Dayeh Department of Physics and Space Sciences Florida Institute of Technology FL 32901 USA Department of Space Science and CSPAR University of Alabama in Hun-tsville Huntsville Alabama 35801 USA Applied Physics Laboratory Johns Hopkins University Laurel MD 20723 USA California Institute of Technology Pasadena CA 91125 USA Southwest Research Institute San Antonio TX 78228 USA University of Texas at San Antonio San Antonio TX 78249 USA

In large Solar Energetic Particle （SEP） events, ions can be accelerated at coronal mass ejection （CmE）-driven shocks to very high energies. The spectra of heavy ions in many large SEP events show features such as roll-overs or spectral breaks. In some events when the spectra are plotted in terms of energy/nucleon, they can be shifted relative to each other to make the spectral breaks align. The amount of shift is charge to mass ratio （Q/A） dependent and varies from event to event. This can be understood if the spectra of heavy ions are organized by the diffusion coefficients （Cohen et al. 2005）. In the work of Li et al. （2009）, the Q/A dependence of the scaling is related to shock geometry when the CmE-driven shock is close to the Sun. For events where multiple in-situ spacecraft observations exist, one may expect that different spacecraft are connected to different portions of the CmE-driven shock that have different shock geometries, therefore yielding different Q/A dependence. In this work, we examine one SEP event which occurred on 2013 November 4. We study the Q/A dependence of the energy scaling for heavy ion spectra using helium, oxygen and iron ions. Observations from STEREO-A, STEREO-B and ACE are examined. We find that the scalings are different for different spacecraft. We suggest that this is because ACE, STEREO- A and STEREO-B are connected to different parts of the shock that have different shock geometries. Our analysis indicates that studying the Q/A scaling of in-situ particle spectra can serve as a powerful tool to remotely examine the shock geometry for large SEP events.

关键词： Sun: particle emission -- acceleration of particles

Land-use change and windstorms legacies drove the recolonization dynamics of laurel forests in Tenerife, Canary islands

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Forest Ecosystems 2023年第1期10卷 113-124页

作者： Vicente Rozas maria A.Garcia-Lopez Jose m.Olano Gabriel Sanguesa-Barreda miguel Garcia-Hidalgo Susana Gomez-Gonzalez Roberto Lopez-Rubio Jose m.Fernandez-Palacios Ignacio Garcia-Gonzalez Laura Lozano-Lopez Paula Garcia-Gonzalez Ana I.Garcia-Cervigon EiFAB-iuFOR Universidad de ValladolidCampus Duques de Soria42004SoriaSpain Departamento de Biologia-IVAGRO Universidad de CadizCampus Rio San Pedro11510Puerto RealSpain Center for Climate and Resilience Research(CR)2 Blanco Encalada 20028370449SantiagoChile Area de Biodiversidad y Conservacion Universidad Rey Juan Carlosc/Tulipan s/n28933MostolesSpain Grupo de Ecologia y Biogeografia Insular Universidad de La Laguna38206La LagunaTenerifeSpain BIOAPLIC Departamento de BotanicaEscola Politecnica Superior de EnxenariaCampus TerraUniversidade de Santiago de CompostelaLugo27002Spain

laurel forests are quite relevant for biodiversity conservation and are among the island ecosystems most severely damaged by human *** the past,Canary laurel forests have been greatly altered by logging,livestock and *** remains of laurel forests are currently protected in the Canary Islands(Spain).However,we miss basic information needed for their restoration and adaptive management,such as tree longevity,growth potential and responsiveness to natural and anthropogenic *** dendrochronological methods,we studied how forest dynamic is related to land-use change and windstorms in two well-preserved laurel forests on Tenerife *** cores were collected from over 80 trees per stand at three stands per *** used ring-width series to estimate tree ages and calculate annual basal area increments(BAI),cumulative diameter increases,and changes indicative of released and suppressed *** tree species were found in all stands,with Laurus novocanariensis,Ilex canariensis and morella faya being the most common *** some individuals were over 100 years old,61.8%-88.9% of the trees per stand established between 1940 and 1970,coinciding with a post-war period of land abandonment,rural exodus and the onset of a tourism *** trees have shown growth rates larger than 1 cm diameter per year and most species have had increasing BAI trends over the past *** growth releases occurred after windstorms at both sites,but the effects of windstorms were site-dependent,with the 1958 storm affecting mainly the eastern tip of the island(Anaga massif)and the 1991 storm the western tip(Teno massif).Given the great ability of laurel forest trees to establish after land use cessation and to increase growth after local disturbances such as windstorms,passive restoration may be sufficient to regenerate this habitat in currently degraded areas.

关键词： Canary islands Dendroecology Disturbance Forest structure macaronesia management cessation Tree rings

Recurrent ectopic pancreatitis of the jejunum and mesentery over a 30-year period

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Hepatobiliary & Pancreatic Diseases International 2011年第2期10卷 218-220页

作者： John CT Wong Charlotte Robinson Edward C Jones Alison Harris Charles Zwirewich Robert Wakefield Richard K Simons Eric m Yoshida Department of medicine Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Department of Radiology Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Department of Pathology and Laboratory medicine Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Department of Surgery Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9 Division of Gastroenterology Department of medicine 2775 Laurel StreetUniversity of British Columbia VancouverBritish ColumbiaCanadaV5Z 1M9

BACKGROUND:Ectopic pancreas is defined as pancreatic tissue found outside its usual anatomical position,with no ductal or vascular communication with the native pancreas. We describe a case of ectopic pancreas of the small bowel and mesentery causing recurrent episodes of pancreatitis, initially suspected on computed tomography(CT)and magnetic resonance cholangiopancreatography(mRCP),and confirmed on histological review of the resection. mETHODS:A 67-year-old woman presented with clinical symptoms and biochemical evidence of *** had similar episodes over the past 30 years with unrevealing investigations,and was concluded to have idiopathic pancreatitis. She underwent CT and mRCP,with findings suggestive of ectopic pancreas,a diagnosis confirmed on histology of the resection. RESULTS:mRCP identified a mass in the proximal small bowel mesentery isointense to the native pancreas,with a small duct draining into a proximal jejunal *** resected specimen consisted of normal parenchyma with lobulated acinar tissue with scattered islets of Langerhans,an occasional ductular structure,and admixed areas of adipose *** patient remained asymptomatic with normal biochemistry six months post-operatively. CONCLUSION:In an individual with abdominal pain,elevated serum amylase/lipase,but imaging findings of a normal native pancreas,ectopic pancreatitis should be considered,and can be evaluated by CT and mRCP.

关键词： ectopic pancreas gastrointestinal tract endoscopic ultrasound computed tomography magnetic resonance cholangiopancreatography

Assessing nest attentiveness of Common Terns via video cameras and temperature loggers

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Avian Research 2020年第3期11卷 284-301页

作者： Jeffery D.Sullivan Paul R.marbán Jennifer m.mullinax David F.Brinker Peter C.mcGowan Carl R.Callahan Diann J.Prosser Natural Systems Analysts Winter ParkFL 32789USA marine Estuarineand Environmental Sciences ProgramUniversity of MarylandCollege ParkMD 20742USA Department of Environmental Science and Technology University of Maryland1443 Animal Sciences BldgCollege ParkMD 20742USA Department of Natural Resources Maryland Natural Heritage ProgramAnnapolisMD 21401USA Chesapeake Bay Field Office U.S.Fish and Wildlife ServiceAnnapolisMD 21401USA U.S.Geological Survey Patuxent Wildlife Research CenterLaurelMD 20708USA.

Background:While nest attentiveness plays a critical role in the reproductive success of avian species,nest attentiveness data with high temporal resolution is not available for many ***,improvements in both video monitoring and temperature logging devices present an opportunity to increase our understanding of this aspect of avian ***:To investigate nest attentiveness behaviors and evaluate these technologies,we monitored 13 nests across two Common Tern(Sterna hirundo)breeding colonies with a paired video camera-temperature logger approach,while monitoring 63 additional nests with temperature loggers *** occurred from may to August of 2017 on Poplar(Chesapeake Bay,maryland,USA)and Skimmer Islands(Isle of Wight Bay,maryland,USA).We examined data respective to four times of day:morning(civil dawn‒11:59),Peak(12:00‒16:00),Cooling(16:01‒civil dusk),and Night(civil dusk‒civil dawn).Results:While successful nests had mostly short duration off-bouts and maintained consistent nest attentiveness throughout the day,failed nests had dramatic reductions in nest attentiveness during the Cooling and Night periods(pment due to predation pressure from a Great Horned Owl(Bubo virginianus).Incubation appeared to ameliorate ambient temperatures during Night,as nests were significantly warmer during Night when birds were on versus off the nest(pmeanwhile,off-bouts during the Peak period occurred during higher ambient temperatures,perhaps due to adults leaving the nest during the hottest periods to perform belly ***,temperature logger data alone had limited ability to predict nest attentiveness status during shorter bouts,with results highly dependent on time of day and bout *** our methods did not affect hatching success(p>0.05),video-monitored nests did have significantly lower clutch sizes(p<0.05).Conclusions:The paired use of iButtons and video ca

关键词： Common Tern iButton Nest attentiveness Sterna hirundo Temperature logger Video monitoring

Anomalous enhancement of ionospheric electron content in the Asian-Australian region during a geomagnetically quiet day

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Anomalous enhancement of ionospheric electron content in the...

Closed-loop superconducting materials discovery

中国科学院地质与地球物理研究所2008学术年会

作者： K.Igarashi m.Nakamura L.J.Paxton National Institute of Information and Communications Technology TokyoJapan. Johns Hopkins University Applied Physics Laboratory LaurelMarylandUSA.

[1]We investigate an event of anomalous enhancement in ionospheric electron content on 28 June 2002 from a network of 70 GPS receivers and a chain of ionosondes distributed around the Asian-Australian *** local sunset,the low-latitude peak electron density of the F layer(NF) was observed to increase by 200%compared to the 27-day median *** environment was quiet during 27-28 June as the SYm-H index was larger than -20 nT and AE was less than 200 nT under conditions of a constant northward interplanetary magnetic field Bz.A continuously enhanced eastward electric field has been identified as the main cause of this effect,though it is not fully consistent with the prediction of Scherliess and Fejer(1997) for wind disturbance dynamo *** observations show that the ionosphere was very disturbed in the Northern Hemisphere during summer even under low geomagnetic *** large ionospheric disturbance may be caused by the combination of the effects due to auroral activity and tides,a combination that still needs further *** work suggests that studying very large day-to-day variability under quiet geomagnetic conditions could reveal more about the coupling processes between the ionosphere and lower atmosphere.

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npj Computational materials 2023年第1期9卷 471-478页

作者： Elizabeth A.Pogue Alexander New Kyle mcElroy Nam Q.Le michael J.Pekala Ian mcCue Eddie Gienger Janna Domenico Elizabeth Hedrick Tyrel m.mcQueen Brandon Wilfong Christine D.Piatko Christopher R.Ratto Andrew Lennon Christine Chung Timothy montalbano Gregory Bassen Christopher D.Stiles Research and Exploratory Development Department Johns Hopkins University Applied Physics Laboratory11100 Johns Hopkins RoadLaurel 20723 MDUSA Department of materials Science and Engineering Northwestern University2220 Campus DriveEvanston 60208 ILUSA Department of materials Science and Engineering Johns Hopkins University3400 N.Charles StreetBaltimore 21218 MDUSA Department of Chemistry Johns Hopkins University3400 N.Charles StreetBaltimore 21218 MDUSA Institute for Quantum matter William H.Miller III Department of Physics and AstronomyJohns Hopkins University3400 N.Charles StreetBaltimore 21218 MDUSA

Discovery of novel materials is slow but necessary for societal ***,we demonstrate a closed-loop machine learning(mL)approach to rapidly explore a large materials search space,accelerating the intentional discovery of superconducting *** experimentally validating the results of the mL-generated superconductivity predictions and feeding those data back into the mL model to refine,we demonstrate that success rates for superconductor discovery can be more than *** four closed-loop cycles,we report discovery of a superconductor in the Zr-In-Ni system,re-discovery of five superconductors unknown in the training datasets,and identification of two additional phase diagrams of interest for new superconducting *** work demonstrates the critical role experimental feedback provides in mL-driven discovery,and provides a blueprint for how to accelerate materials progress.

关键词： discovery materials loop

Plasma Heating Induced by Tadpole-like Downflows in the Flaring Solar Corona

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The Innovation 2021年第1期2卷 137-143页

作者： Tanmoy Samanta Hui Tian Bin Chen Katharine KReeves mark C.m.Cheung Angelos Vourlidas Dipankar Banerjee Department of Physics and Astronomy George Mason UniversityFairfaxVA 22030USA Johns Hopkins University Applied Physics Laboratory LaurelMD 20723USA School of Earth and Space Sciences Peking UniversityBeijing 100871Peopleʼs Republic of China Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100012Peopleʼs Republic of China New Jersey Institute of Technology NewarkNJ 07102USA Harvard-Smithsonian Center for Astrophysics CambridgeMA 02138USA Lockheed martin Solar and Astrophysics Laboratory Palo AltoCA 94304USA Aryabhatta Research Institute of Observational Sciences BeluwakhanUttarakhand 263001India Part of this work was done during the postdoc appointment of T.S.at Peking University BeijingPeopleʼs Republic of China

As one of the most spectacular energy release events in the solar system,solar flares are generally powered by magnetic reconnection in the solar *** a result of the re-arrangement of magnetic field topology after the reconnection process,a series of new looplike magnetic structures are often formed and are known as flare loops.A hot diffuse region,consisting of around 5–10 mK plasma,is also observed above the loops and is called a supra-arcade ***,dark,tadpole-like structures are seen to descend through the bright supra-arcade *** remains unclear what role these so-called supra-arcade downflows(SADs)play in heating the flaring coronal *** we show a unique flare observation,where many SADs collide with the flare loops and strongly heat the loops to a temperature of 10–20 *** of these interactions generate clear signatures of quasi-periodic enhancement in the full-Sun-integrated soft X-ray emission,providing an alternative interpretation for quasi-periodic pulsations that are commonly observed during solar and stellar flares.

关键词： Sun:corona Sun:solar flare Sun:magnetic reconnection Sun:plasma heating

In situ evidence of a near-Earth X-line at～11RE

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In situ evidence of a near-Earth X-line at～11RE