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predicting the potential distribution of invasive exotic species using GIS and information-theoretic approaches:A case of ragweed(Ambrosia artemisiifolia L.)distribution in China

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Chinese Science Bulletin 2007年第9期52卷 1223-1230页

作者： CHEN Hao CHEN LiJun thomas p. ALBRIGHT School of Remote Sensing Information Engineering Wuhan University Wuhan 430079 China National Geomatics Center of China Beijing 100080 China SAIC USGS Center for EROS Sioux Falls SD 57198 USA Department of Zoology University of Wisconsin-Madison WI USA

Invasive exotic species pose a growing threat to the economy,public health,and ecological integrity of nations worldwide. Explaining and predicting the spatial distribution of invasive exotic species is of great importance to prevention and early warning efforts. We are investigating the potential distribution of invasive exotic species,the environmental factors that influence these distributions,and the ability to predict them using statistical and information-theoretic approaches. For some species,detailed presence/absence occurrence data are available,allowing the use of a variety of standard statistical techniques. However,for most species,absence data are not available. presented with the challenge of developing a model based on presence-only information,we developed an improved logistic regres-sion approach using Information Theory and Frequency Statistics to produce a relative suitability map. This paper generated a variety of distributions of ragweed(Ambrosia artemisiifolia L.) from logistic regression models applied to herbarium specimen location data and a suite of GIS layers including climatic,topographic,and land cover information. Our logistic regression model was based on Akaike's Information Criterion(AIC) from a suite of ecologically reasonable predictor variables. Based on the results we provided a new Frequency Statistical method to compartmentalize habitat-suitability in the native range. Finally,we used the model and the compartmentalized criterion developed in native ranges to “project” a potential distribution onto the exotic ranges to build habitat-suitability maps.

关键词：外来入侵物种潜在分布预测信息论 GIS 豚草属

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Information Divergence and the Generalized Normal Distribution:A Study on Symmetricity

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Communications in Mathematics and Statistics 2021年第4期9卷 439-465页

作者： thomas L.Toulias Christos p.Kitsos Department of Electrical and Electronics Engineering University of West AtticaCampus 1Egaleo12243 AthensGreece Department of Informatics and Computer Engineering University of West AtticaCampus 1Egaleo12243 AthensGreece

This paper investigates and discusses the use of information divergence,through the widely used Kullback–Leibler(KL)divergence,under the multivariate(generalized)γ-order normal distribution(γ-GND).The behavior of the KL divergence,as far as its symmetricity is concerned,is studied by calculating the divergence of γ-GND over the Student’s multivariate t-distribution and vice *** special cases are also given and ***,three symmetrized forms of the KL divergence,i.e.,the Jeffreys distance,the geometric-KL as well as the harmonic-KL distances,are computed between two members of the γ-GND family,while the corresponding differences between those information distances are also discussed.

关键词： Kullback-Leibler divergence Jeffreys distance Resistor-average distance Multivariateγ-order normal distribution Multivariate Student’s t-distribution Multivariate Laplace distribution

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Evaluation of diverse classification approaches for land use/cover mapping in a Mediterranean region utilizing Hyperion data

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International Journal of Digital Earth 2014年第3期7卷 194-216页

作者： Alata Elatawneh Chariton Kalaitzidis George p.petropoulosc thomas Schneider Institute of Forest Management Technische Universität Muünchen(TUM)85354 FreisingGermany Department of Geoinformation in Environmental Management Mediterranean Agronomic Institute of Chania(MAICh)Chania 73100Greece INFOCOSMOS 13341 AthensGreece

Information on Earth’s land surface cover is commonly obtained through digital image analysis of data acquired from remote sensing *** this study,we evaluated the use of diverse classification techniques in discriminating land use/cover types in a typical Mediterranean setting using Hyperion *** this purpose,the spectral angle mapper(SAM),the object-based and the non-linear spectral unmixing based on artificial neural networks(ANNs)techniques were applied.A further objective had been to investigate the effect of two approaches for training sites selection in the SAM classification,namely of the pixel purity index(ppI)and of the direct selection of training points from the Hyperion imagery assisted by a QuickBird imagery and field-based training *** classification outperformed the other techniques with an overall accuracy of 83%.Sub-pixel classification based on the ANN showed an overall accuracy of 52%,very close to that of SAM(48%).SAM applied using the training sites selected directly from the Hyperion imagery supported by the QuickBird image and the field visits returned an increase accuracy by 16%.Yet,all techniques appeared to suffer from the relatively low spatial resolution of the Hyperion imagery,which affected the spectral separation among the land use/cover classes.

关键词： Hyperion Earth’s land use/cover mapping digital image analysis spectral angle mapper sub-pixel classification artificial neural networks Greece

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Radio observations of the first three-months of Fermi AGN at 4.8 GHz

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Research in Astronomy and Astrophysics 2012年第2期12卷 147-157页

作者： Nicola Marchili thomas p.Krichbaum Lars Fuhrmann Anton Zensus Max-plank-Institut fr Radioastronomie

Using the Urumqi 25 m radio telescope, sources from the first three months of the Fermi-large area telescope detected active galactic nuclei （AGN） catalog with a declination of 〉 0° were observed in 2009 at 4.8 GHz. The radio flux density ap- peared to correlate with the γ-ray intensity. Intra-day variability （IDV） observations were performed in March, April and May 2009 for 42 selected γ-ray bright blazars, and ~60% of them showed evidence of flux variability at 4.8 GHz during the IDV observations. The IDV detection rate was higher than that in previous flat-spectrum AGN samples. IDV appeared more often in the very long baseline interferometry-core dominant blazars, and the non-IDV blazars showed relatively ＂steeper＂ spectral in- dices than the IDV blazars. pronounced inter-month variability was also found in two BL Lac objects： J0112＋2244 and J0238＋1636.

关键词： galaxies: active - quasars: general - radio continuum: galaxies -gamma-rays: observations

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Light tuning CO/H_(2)composition on Ag:Unraveling CO_(2)mass transfer and electron-phonon coupling in plasmon-enhanced electrocatalysis

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Nano Research 2025年第1期18卷 173-185页

作者： Rui Lin Dong Fan Luca MBerger thomas possmayer Yu Zhou Jiexin Zhu Xingbao Chen Wen Luo Lars Allmendinger Andreas Tittl Leonardo de Souza Menezes Guillaume Maurin Shihe Yang and Stefan AMaier Nanoinstitute Munich Faculty of PhysicsLudwig-Maximilians-Universität München80539 MunichGermany Institut Charles Gerhardt Montpellier UMR 5253 CNRS ENSCM UniversitéMontpellierPlace E.Bataillon34090 MontpellierFrance Guangdong provincial Key Lab of Nano-Micro Material Research School of Advanced MaterialsPeking University Shenzhen Graduate SchoolShenzhen 518055China State Key Laboratory of Advanced Technology for Materials Synthesis and processing Wuhan University of TechnologyWuhan 430070China Faculty of Chemistry and pharmacy Ludwig-Maximilians-Universität München81377 MunichGermany Departamento de Física Universidade Federal de Pernambuco50670-901 Recife-PEBrazil School of physics and Astronomy Monash University Clayton CampusMelbourneVictoria 3800Australia Department of physics Imperial College LondonSW72AZ LondonUK

plasmon-enhanced electrocatalysis(pEEC)is an emerging approach to mitigate CO_(2)*** mechanisms behind CO_(2)adsorption and reduction at the catalyst-electrolyte interface in pEEC still need to be further ***,we employ a well-defined Ag nanostructure to elucidate these pivotal *** shining light with wavelengths of 625,525,405 nm on Ag,an adjustable CO/H_(2)ratio from 35 to 1 can be *** reaction pathway changing under plasmonic excitation does not originate from the lowered CO_(2)mass transfer in the vicinity of Ag,as the electrochemical quartz crystal microbalance results unravel that a slightly elevated temperature in bulk electrolyte caused by light irradiation cannot weaken the CO_(2)adsorption at the Ag catalyst-electrolyte *** calculations reveal that optical excitation towards shorter wavelengths leads to a progressive lowered energy barrier for H_(2)formation together with an enhanced energy barrier for^(*)COOH *** thermodynamically suppressed,CO_(2)reduction can still be improved kinetically by optimizing the excitation wavelength and intensity,being accompanied with the enhanced *** absorption spectroscopy results further correlate the higher photocurrent with a prolonged electron-phonon coupling time,verifying that the improvement of CO_(2)reduction kinetics in pEEC can be realized by hot electron harnessing.

关键词： plasmonic catalysis photoelectrochemical CO_(2)reduction CO/H_(2)ratio hot electron generation electronphonon coupling thermal effect

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Nanomechanical and Chemical Mapping of the Structure and Interfacial properties in Immiscible Ternary polymer Systems

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Chinese Journal of polymer Science 2021年第6期39卷 651-658,I0004页

作者： Hao-Xuan Li thomas pRussell Dong Wang State Key Laboratory of Organic-Inorganic Composites&Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China polymer Science and Engineering Department University of Massachusetts AmherstMassachusetts 01003United States Materials Sciences Division Lawrence Berkeley National Laboratory1 Cyclotron RoadBerkeleyCalifornia 94720United States

It is a challenge to identify each phase in a multi-component polymer system and uniquely determine the interfacial properties between the different *** atomic force microscopy nanomechanical mapping(AFM-NM)and AFM-based infrared spectroscopy(AFM-IR),we identify each phase,visualize structural developments,and determine the interfacial properties in a blend of three polymers:high-density polyethylene(HDpE),polyamide(pA6)and poly(styrene-b-ethylene-co-butylene-b-styrene)(SEBS).Each phase can be identified from the Young’s modulus,along with the structural development within the phases before and after *** interfacial widths between HDpE/pA6,HDpE/SEBS and SEBS/pA6 were determined independently in one measurement from a Young’s modulus *** structural,mechanical property development and identity of the phases were determined by AFM-NM,while AFM-IR,providing complementary chemical information,identified interfacial reactions,showed the chemical affinity of a compatibilizer with the component phases,and mapped the distribution of the compatibilizer in the ternary polymer *** chemical,structural and interfacial information obtained by these measurements provide information that is essential for producing mechanically robust materials from incompatible mixtures of polymers.

关键词： AFM nanomechanical mapping AFM infrared spectroscopy Multi-component systems Interfacial structure Interfacial properties

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Structural and luminescence enhancement properties of Eu^(3+)/Ag nanocrystallites doped SiO_2-TiO_2 matrices

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Journal of Rare Earths 2013年第5期31卷 441-448页

作者： Arun Kumar K V Revathy K p prathibha Vasudevan Sunil thomas Biju p R Unnikrishnan N V School of pure & Applied physics Mahatma Gandhi University

We reported here the structural and optical characterisation of silver nanocrystallites/Eu3＋：SiO2-TiO2 matrices synthesised through sol-gel route. Structural characterisations were done by using energy dispersive spectroscopy （EDX）, X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FTIR）, atomic force microscope （AFM） and transmission electron microscopy （TEM） measurements and optical characterisations were performed by absorption and emission spectroscopy. The TEM and XRD measurements confirmed the presence of nanocrystals. A broad absorption band was observed due to surface plasmon resonance of silver nanocrystals. The effect of silver nanocrystals on the emission spectrum of Eu3＋ doped SiO2-TiO2 matrices was discussed. An attempt was made to explain this fluorescence enhancement by invoking phenomena such as energy transfer, asymmetry ratio, surface plasmon, surface roughness, crystallinity and grain boundary. Our analysis, based on the experimental results, suggested that all the phenomena except crystallinity and grain boundary had favourable effects on fluorescence enhancement. We also estimated the relevant parameters associated with the phenomena that affected the fluorescence emission from the Eu3＋ ions in the matrix. It was seen that the theoretical estimate of fluorescence enhancement agreed well with the experimental estimate.

关键词： sol-gel luminescence SiO2-TiO2 silver nanoparticles rare earths

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Th1 cytokines promote T-cell binding to antigen-presenting cells via enhanced hyaluronan production and accumulation at the immune synapse

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Cellular & Molecular Immunology 2010年第3期7卷 211-220页

作者： paul L Bollyky stephen p Evanko Rebecca p Wu Susan potter-perigo S Alice Long Brian Kinsella Helena Reijonen Kelly Guebtner Brandon Teng Christina K Chan Kathy R Braun John A Gebe Gerald T Nepom thomas N Wight Benaroya Research Institute SeattleWAUSA

Hyaluronan(HA)production by dendritic cells(DCs)is known to promote antigen presentation and to augment T-cell activation and *** hypothesized that pericellular HA can function as intercellular‘glue’directly mediating T cell–DC *** primary human cells,we observed HA-dependent binding between T cells and DCs,which was abrogated upon pre-treatment of the DCs with 4-methylumbelliferone(4-MU),an agent which blocks HA ***,T cells regulate HA production by DCs via T cell-derived cytokines in a T helper(Th)subset-specific manner,as demonstrated by the observation that cell-culture supernatants from Th1 but not Th2 clones promote HA *** effects were seen upon the addition of exogenous Th1 cytokines,IL-2,interferon c(IFN-c)and tumor necrosis factor a(TNF-a).The critical factors which determined the extent of DC–T cell binding in this system were the nature of the pre-treatment the DCs received and their capacity to synthesize HA,as T-cell clones which were pre-treated with monensin,added to block cytokine secretion,bound equivalently irrespective of their Th *** data support the existence of a feedforward loop wherein T-cell cytokines influence DC production of HA,which in turn affects the extent of DC–T cell *** also document the presence of focal deposits of HA at the immune synapse between T-cells and ApC and on dendritic processes thought to be important in antigen *** data point to a pivotal role for HA in DC–T cell interactions at the IS.

关键词： dendritic cell hyaluronan immune synapse pericellular matrix Th1

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Low hypoxia inducible factor-1α(HIF-1α)expression in testicular germ cell tumors--a major reason for enhanced chemosensitivity?

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Chinese Journal of Cancer Research 2017年第4期29卷 374-378页

作者： niraj shenoy roxana dronca fernando quevedo stephen a boorjian john cheville brian costello manish kohli thomas witzig lance pagliaro division of oncology mayo clinicRochesterMN 55905usa department of urology mayo clinicRochesterMN 55905usa division of clinical pathology mayo clinicRochesterMN 55905usa

The molecular basis for enhanced chemosensitivity of testicular germ cell tumors （GCT） has been an area of great interest, as it could potentially give us therapeutic leads in other resistant malignancies. Thus far, however, the increased sensitivity of C＆T has been variously attributed to multiple factors -- an inability to detoxify cisplatin, a lack of export pumps, an inability to repair the DNA damage, an intact apoptotic cascade and lack of p53 mutation; but a unifying underlying etiology leading to the aforementioned processes and having a translational implication has so far been elusive. Herein, we offer evidence to support a potential significant role for the previously demonstrated low hypoxia inducible factor-la （HIF-la） expression in mediating the general exquisite chemosensitivity of testicular GCT, through the aforementioned processes. This molecular mechanism based hypothesis could have a significant translational implication in platinum refractory GCT as well as other platinum resistant malignancies.

关键词： Hypoxia inducible factor-la (HIF-la) testicular germ cell tumor chemosensitivity

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Efficacy of Detoxsan~? powder on diarrhea caused by gastrointestinal neuroendocrine tumors

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World Journal of Gastroenterology 2019年第17期25卷 2133-2143页

作者： thomas Langbein Wilfried Dathe Anika Deuerling Richard p Baum Theranostics Center for Molecular Radiotherapy and Molecular Imaging Zentralklinik Bad Berka Scientific Managment Heck Bio-Pharma GmbH

BACKGROUND patients with neuroendocrine tumors(NETs) of the gastrointestinal tract suffer frequently from chronic diarrhea. A well characterized medical advice containing zeolite(Detoxsan~? powder) was applied to patients suffered from therapyrefractory diarrhea either by its frequency or by watery stool, despite receiving standard pharmacotherapy according to the guidelines for carcinoid syndrome and comorbidities. Detoxsan~? powder acts as an adsorbent and might reduce significantly symptoms of diarrhea in patients suffering from *** To overcome the therapy-refractory diarrhea of patients with NETs by the zeolite containing medical advice Detoxsan~? *** A total of 20 patients(12 female and 8 male) suffering from diarrhea either by its frequency or from watery stool caused by NETs were included. In each patient,the diagnosis had been confirmed by histology and somatostatin receptors expression proven by positron emission tomography/computed tomography using Ga-68-labeled somatostatin analogs. All patients received standard-of-care pharmacotherapy and were additionally given Detoxsan~? powder as an extemporaneous drug containing 90% natural Cuban zeolite and 10% magnesium aspartate. Recommended daily dosage ranges between 3 g once to three times per day. Each day dose and bowel movements were documented by the patients themselves in a pre-defined table. Additionally to the bowel movements quantitative determinations of serotonin, urea, creatinine and single ions were performed within the serum of the patients by commercially available equipment used as a matter of routine in the *** All patients enrolled in this pilot study did not only suffer from NETs, but also from comorbidities and treatment-resistant diarrhea. There was insufficient control of diarrhea, most probably due to the secretion of hormones like serotonin produced by the slowly growing and highly differentiated NETs. All patients only took Detoxsan~? powder as an antidiarrhea

关键词： Neuroendocrine tumor Diarrhea Carcinoid syndrome Treatment Clinoptilolite Mordenite Zeolite

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