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NEAR'S CLOSE fLYBY Of C-TYPE ASTEROID 253 MATHILDE

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紫金山天文台台刊 1998年第2期 44-50页

作者： james f.bell iii the NEAR Science Team Cornell University Department of Astronomy Ithaca NY 14853-6801 USA

On June 27, 1997, the Near Earth Asteroid Rendezvous (NEAR) spacecraft flew within 1200km of the main belt asteroid 253 Mathilde. Previous observations of Mathilde had revealed it to be a C-type asteroid with an astonishingly-long rotation period of 17.4 days, an albedo of 3.8%, and a mean diameter of 60 km. Observations by NEAR reveal that Mathilde has a roughly triaxial shape of 66 × 48 × 46 km diameter and a mass of 1. 02 × 10 g, implying a mean density of only 1. 3g/cm3 . The surface of Mathilde was observed to be saturated with large impact craters, showing a range of visible topography in excess of 5 km. Multispectral observations did not reveal any substantial color differences across the surface, and coverage at multiple phase angles was used to derive a preliminary albedo of 3. 5 % to 5% .The low observed density, lack of color variations, and low albedo all suggest that Mathilde may be a primitive, carbon - rich object with an interior that contains substantial pore space.

关键词：小行星飞船紫金山天文台探测

PRELIMINARY SCIENCE RESULTS fROM THE MARS PATHfINDER MISSION

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紫金山天文台台刊 1998年第2期 22-32页

作者： james f.bell iii Nicolas Thomas the Mars Pathfinder Science Team Cornell University Department of Astronomy Ithaca NY 14853-6801 USAMax Planck Institute für Aeronomie D-37189 Katlenberg-Lindau Germany

The NASA Mars Pathfinder mission successfully carried out the first robotic exploration of the Martian surface since the Viking Lander missions of the late 1970s. The mission is one of the new "Discovery class"spacecraft designed t0 demonstrate the concepts of low cost, rapid development, innovative technology, and small science and operational teams. Pathfinder landed on Mars on July 4, 1997 near 19°N, 33°W, at the mouth of an ancient outflow channel. The mission operated for 83 days on the Martian surface, returning thousands of multispectral images, millions of meteorological measurements, chemical analyses of nearly 20 rock and soil samples, and data from a number of other engineering and technology experiments. Key scientific results from the initial analyses of the compositional and mineralogic data returned include: (1)Evidence that some rocks at the landing site may have higher Si content than"typical"terrestrial basalts or the SNC meteorites, possibly implying a greater degree of crustal

关键词：初步成果火星探测器天文台紫金山宋本

Bolstering integrity in environmental data science and machine learning requires understanding socioecological inequity

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frontiers of Environmental Science & Engineering 2024年第5期18卷 171-179页

作者： Joe f.Bozeman iii School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlantaGA30332USA School of Public Policy Georgia Institute of TechnologyAtlantaGA30332USA

Socioecological inequity in environmental data science—such as inequities deriving from data-driven approaches and machine learning(ML)—are current issues subject to debate and *** is growing consensus around embedding equity throughout all research and design domains—from inception to administration,while also addressing procedural,distributive,and recognitional ***,practically doing so may seem onerous or daunting to *** current perspective helps to alleviate these types of concerns by providing substantiation for the connection between environmental data science and socioecological inequity,using the Systemic Equity framework,and provides the foundation for a paradigmatic shift toward normalizing the use of equity-centered approaches in environmental data science and ML *** the integrity of environmental data science and ML is just beginning from an equity-centered tool development and rigorous application *** this end,this perspective also provides relevant future directions and challenges by overviewing some meaningful tools and strategies—such as applying the Wells-Du Bois Protocol,employing fairness metrics,and systematically addressing irreproducibility;emerging needs and proposals—such as addressing data-proxy bias and supporting convergence research;and establishes a ten-step path ***,the work that environmental scientists and engineers do ultimately affect the well-being of us all.

关键词： Equity Bias Machine Learning Data Science Justice Systemic Equity

Berberine for prevention of dementia associated with diabetes and its comorbidities:A systematic review

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Journal of Integrative Medicine 2020年第2期18卷 125-151页

作者： Noriko Shinjyo james Parkinson Jimmy bell Tatsuro Katsuno Annie Bligh Department of Infection and Host Defense Graduate School of MedicineChiba UniversityChuo-kuChiba 260-8670Japan Department of Life Sciences Faculty of Science and Technology at the University of WestminsterLondon W1W 6UWUnited Kingdom Kashiwanoha Clinic of East Asian Medicine Chiba University HospitalKashiwaChiba 277-0882Japan School of Health Sciences Caritas Institute of Higher EducationTseung Kwan ONT 999077Hong KongChina

Background: A growing number of epidemiological studies indicate that metabolic syndrome(MetS) and its associated features play a key role in the development of certain degenerative brain disorders, including Alzheimer’s disease and vascular dementia. Produced by several different medicinal plants, berberine is a bioactive alkaloid with a wide range of pharmacological effects, including antidiabetic ***, it is not clear whether berberine could prevent the development of dementia in association with ***: To give an overview of the therapeutic potential of berberine as a treatment for dementia associated with *** strategy: Database searches A and B were conducted using Pub Med and Science Direct. In search A,studies on berberine’s antidementia activities were identified using “berberine” and “dementia” as search terms. In search B, recent studies on berberine’s effects on diabetes were surveyed using “berberine” and“diabetes” as search *** criteria: Clinical and preclinical studies that investigated berberine’s effects associated with Met S and cognitive dysfunction were *** extraction and analysis: Data from studies were extracted by one author, and checked by a second;quality assessments were performed independently by two ***: In search A, 61 articles were identified, and 22 original research articles were selected. In search B, 458 articles were identified, of which 101 were deemed relevant and selected. Three duplicates were removed, and a total of 120 articles were reviewed for this study. The results demonstrate that berberine exerts beneficial effects directly in the brain: enhancing cholinergic neurotransmission, improving cerebral blood flow, protecting neurons from inflammation, limiting hyperphosphorylation of tau and facilitating b-amyloid peptide clearance. In addition, evidence is growing that berberine is effective against diabetes and associated disorders, such as atherosclerosis

关键词： Berberine Diabetes Dementia Alzheimer’s disease Vascular dementia

Interaction forces between soft magnetic particles in uniform and non-uniform magnetic fields

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Acta Mechanica Sinica 2010年第6期26卷 921-929页

作者： Ayyoub Mehdizadeh james f.Klausner Nima Rahmatian Department of Mechanical and Aerospace Engineering University of FloridaP.O.Box 116300GainesvilleFL 32611-6300USA

The influence of the magnetization of a soft magnetic sphere on the surrounding magnetic field is measured and *** interaction force between two soft magnetic particles is directly measured using an ultra precision load sensor in uniform and non-uniform magnetic fields. The interaction force largely follows an inverse fourth power law as a function of separation distance between particle centers. At small distances,the effect of magnetization of one particle on the magnetization of its adjacent particle causes the attractive（repulsive） force to be larger（smaller） than that predicted by the inverse fourth power *** theoretical prediction based on a modified dipole model,that takes into account the coupling effect of the magnetization among soft magnetic particles,gives excellent agreement with the measured force in a uniform magnetic *** interaction force under a non-uniform applied magnetic field can be reasonably predicted using the dipole-dipole interaction model when the local magnetic field is used to determine the magnetization.

关键词： Magnetic force Magnetic charge model Magnetic dipole model Soft magnetic particle

Expanding the donor pool: Hepatitis C, hepatitis B and human immunodeficiency virus-positive donors in liver transplantation

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World Journal of Gastroenterology 2019年第47期25卷 6799-6812页

作者： james f Crismale Jawad Ahmad Division of Liver Diseases Icahn School of Medicine at Mount Sinai

Liver transplantation(LT)remains the best option for patients with end-stage liver disease but the demand for organs from deceased donors continues to outweigh the available *** advent of highly effective anti-viral treatments has reduced the number of patients undergoing LT for hepatitis C(HCV)and hepatitis B(HBV)related liver disease and yet the number of patients waiting for LT continues to increase,driven by an increase in the patients listed with a diagnosis of cirrhosis due to non-alcoholic steatohepatitis and alcoholrelated liver *** addition,human immunodeficiency virus(HIV)infection,which was previously a contra-indication for LT,is no longer a fatal disease due to the effectiveness of HIV therapy and patients with HIV and liver disease are now developing indications for *** rising demand for LT is projected to increase further in the future,thus driving the need to investigate potential means of expanding the pool of potential *** mechanism for doing so is utilizing organs from donors that previously would have been discarded or used only in exceptional circumstances such as HCV-positive,HBV-positive,and HIVpositive *** advent of highly effective anti-viral therapy has meant that these organs can now be used with excellent outcomes in HCV,HBV or HIV infected recipients and in some cases uninfected recipients.

关键词： Hepatitis C Hepatitis B Human immunodeficiency virus Liver transplantation

Modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies

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Research in Astronomy and Astrophysics 2011年第12期11卷 1429-1448页

作者： james Q.feng C.f.Gallo Superconix Inc 2440 Lisbon AvenueLake ElmoMN 55042USA

We present an efficient, robust computational method for modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies. With appropriate mathematical treatments, the apparent numerical difficulties associated with singularities in computing elliptic integrals are completely removed. Using a boundary element discretization procedure, the governing equations are transformed into a linear algebra matrix equation that can be solved by straightforward Gauss elimination in one step without further iterations. The numerical code implemented according to our algorithm can accurately determine the surface mass density distribution in a disk galaxy from a measured rotation curve （or vice versa）. for a disk galaxy with a typical flat rotation curve, our modeling results show that the surface mass density monotonically decreases from the galactic center toward the periphery, according to Newtonian dynamics. In a large portion of the galaxy, the surface mass density follows an approximately exponential law of decay with respect to the galactic radial coordinate. Yet the radial scale length for the surface mass density seems to be generally larger than that of the measured brightness distribution, suggesting an increasing mass-tolight ratio with the radial distance in a disk galaxy. In a nondimensionalized form, our mathematical system contains a dimensionless parameter which we call the ＂galactic rotation number＂ that represents the gross ratio of centrifugal force and gravitational force. The value of this galactic rotation number is determined as part of the numerial solution. Through a systematic computational analysis, we have illustrated that the galactic rotation number remains within 4-10% of 1.70 for a wide variety of rotation curves. This implies that the total mass in a disk galaxy is proportional to V02 Rg, with V0 denoting the characteristic rotation velocity （such as the ＂flat＂ value in a typical ro- tation curve） and Rg the radius of the galacti

关键词： galaxy: disk -- galaxies: general -- galaxies: kinematics and dynamics -- galaxies: structure -- methods: numerical and analytical

Burrowing Richardson's ground squirrels affect plant seedling assemblages via environmental but not seed bank changes

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Current Zoology 2020年第3期66卷 219-226页

作者： Levi J.Newediuk james f.Hare Department of Biological Sciences University of ManitobaWinnipegManitobaCanada R3T 2N2

In grassland ecosystems,burrowing mammals create disturbances,providing habitat for animal species and increasing plant community *** investigated whether seedling assemblages on Richardson's ground squirrel Urocitellus richardsonii mounds result from seed rearrangement or environmental changes that favor germination of certain species over *** test whether ground squirrels rearrange the seed bank by burrowing,we compared seed compositions among mounds,burrows,and undisturbed *** test whether ground squirrels change environmental conditions,we compared soil nitrate and bare ground cover on and off *** also compared seedlings that germinated on mounds with seedlings that germinated on artificial disturbances from which we removed aboveground *** nitrate and bare ground cover were significantly higher on mounds than artificial *** seed richness and abundance did not differ among mounds,burrows,and undisturbed soil,seedling richness was reduced on mounds relative to artificial *** disturbance favors seedlings that can capitalize on bare ground availability but are less able to immobilize nitrate,as opposed to perennial species that immobilize more nitrate but take longer to *** results suggest that Richardson's ground squirrels act as ecosystem engineers,although future research following succession on ground squirrel mounds is necessary to understand how they influence plant communities past the seedling stage.

关键词： burrowing disturbance ecosystem engineering Richardsons ground squirrel seed bank seedling species composition

Perceptual tolerance neighborhood-based similarity in content-based image retrieval and classification

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International Journal of Intelligent Computing and Cybernetics 2012年第2期5卷 164-185页

作者： Amir H.Meghdadi james f.Peters Electrical and Computer Engineering University of ManitobaWinnipegCanada School of Mathematics University of HyderabadHyderabadIndia

Purpose–The purpose of this paper is to demonstrate the effectiveness and advantages of using perceptual tolerance neighbourhoods in tolerance space-based image similarity measures and its application in content-based image classification and ***/methodology/approach–The proposed method in this paper is based on a set-theoretic approach,where an image is viewed as a set of local visual *** method also includes a tolerance relation that detects the similarity between pairs of elements,if the difference between corresponding feature vectors is less than a threshold 2(0,1).findings–It is shown that tolerance space-based methods can be successfully used in a complete content-based image retrieval(CBIR)***,it is shown that perceptual tolerance neighbourhoods can replace tolerance classes in CBIR,resulting in more accuracy and less ***/value–The main contribution of this paper is the introduction of perceptual tolerance neighbourhoods instead of tolerance classes in a new form of the Henry-Peters tolerance-based nearness measure(tNM)and a new neighbourhood-based tolerance-covering nearness measure(tcNM).Moreover,this paper presents a side–by–side comparison of the tolerance space based methods with other published methods on a test dataset of images.

关键词： Image similarity Nearness measure Distance measurement Content-based image retrieval(CBIR) Perceptual tolerance neighbourhoods Tolerance spaces Tolerances Measurement