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Real-Time Static Hand Gesture Recognition for American Sign Language (ASL) in Complex Background

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Journal of Signal and Information Processing 2012年第3期3卷 364-367页

作者： Jayashree R. Pansare Shravan H. Gawande maya Ingle Devi Ahilya University m. E. Society’s College of Engineering

Hand gestures are powerful means of communication among humans and sign language is the most natural and expressive way of communication for dump and deaf people. In this work, real-time hand gesture system is proposed. Experimental setup of the system uses fixed position low-cost web camera with 10 mega pixel resolution mounted on the top of monitor of computer which captures snapshot using Red Green Blue [RGB] color space from fixed distance. This work is divided into four stages such as image preprocessing, region extraction, feature extraction, feature matching. First stage converts captured RGB image into binary image using gray threshold method with noise removed using median filter [medfilt2] and Guassian filter, followed by morphological operations. Second stage extracts hand region using blob and crop is applied for getting region of interest and then “Sobel” edge detection is applied on extracted region. Third stage produces feature vector as centroid and area of edge, which will be compared with feature vectors of a training dataset of gestures using Euclidian distance in the fourth stage. Least Euclidian distance gives recognition of perfect matching gesture for display of ASL alphabet, meaningful words using file handling. This paper includes experiments for 26 static hand gestures related to A-Z alphabets. Training dataset consists of 100 samples of each ASL symbol in different lightning conditions, different sizes and shapes of hand. This gesture recognition system can reliably recognize single-hand gestures in real time and can achieve a 90.19% recognition rate in complex background with a “minimum-possible constraints” approach.

关键词： Image Preprocessing Region Extraction Feature Extraction median Filter ASL

Noninvasive Low-Intensity Focused Ultrasound mediates Tissue Protection following Ischemic Stroke

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Biomedical Engineering Frontiers 2022年第1期3卷 356-366页

作者： Alexandra m.Kaloss Lauren N.Arnold Eman Soliman maya Langman Nathalie Groot Eli Vlaisavljevich michelle H.Theus Department of Biomedical Sciences and Pathobiology Virginia TechBlacksburgVA 24061USA Department of Biomedical Engineering and mechanics Virginia TechBlacksburg VA 24061USA Center for Engineered Health Virginia TechBlacksburg Virginia 24061USA

Objective and Impact *** study examined the efficacy and safety of pulsed,low-intensity focused ultrasound(LIFU)and determined its ability to provide neuroprotection in a murine permanent middle cerebral artery occlusion(pmCAO)*** ultrasound(FUS)has emerged as a new therapeutic strategy for the treatment of ischemic stroke;however,its nonthrombolytic properties remain ***,we examined how LIFU influenced neuroprotection and vascular changes following *** to the critical role of leptomeningeal anastomoses or pial collateral vessels,in cerebral blood flow restoration and tissue protection following ischemic stroke,we also investigated their growth and *** were exposed to transcranial LIFU(fundamental frequency:1.1 mHz,sonication duration:300 ms,interstimulus interval:3 s,pulse repetition frequency:1 kHz,duty cycle per pulse:50%,and peak negative pressure:-2.0 mPa)for 30 minutes following induction of pmCAO and then evaluated for infarct volume,blood-brain barrier(BBB)disruption,and pial collateral remodeling at 24 hrs *** found significant neuroprotection in mice exposed to LIFU compared to mock *** findings correlated with a reduced area of IgG deposition in the cerebral cortex,suggesting attenuation of BBB breakdown under LIFU *** also observed increased diameter of CD31-postive microvessels in the ischemic *** observed no significant difference in pial collateral vessel size between FUS and mock treatment at 24 hrs *** data suggests that therapeutic use of LIFU may induce protection through microvascular remodeling that is not related to its thrombolytic activity.

关键词： Focus repetition treatment

Remediation of Heavy metal (Cd, Cr, Cu, Co, and Ni) Ions from Kaolinite Clay Using molecular micelles Chelators and D-Optimum Experimental Design

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Journal of Environmental Protection 2013年第8期4卷 789-795页

作者： Sayo O. Fakayode Ashley m. Taylor maya mcCoy Sri Lanka Owen Whitney E. Stapleton Carmen Grady David A. Pollard Department of Chemistry Winston-Salem State University Winston-Salem USA

This study investigated the potential utility of poly (sodium N-undecanoyl-L-leucyl-valinate) (poly-L-SULV), poly (sodium N-undecanoyl-L-leucyl-alanate) (poly-L-SULA), and poly (sodium N-undecanoyl-glycinate) (poly-SUG) molecular micelles (mms) as chelators for heavy metal (Cd, Cr, Cu, Co, and Ni) ion remediation of kaolinite clay using D-optimum experimental design. D-optimum experimental design was employed to simultaneously investigate the influence of design variables such as the buffer pH, chelator concentration, and centrifuge speed to evaluate the optimum conditions and to reduce the time and cost of metal ion remediation. The partition coefficients of the metal ion concentrations between the kaolinite clay and chelator equilibrium were also evaluated. In addition, the influence of metal ion concentrations on the remediation capability of the chelators was evaluated by conducting remediation studies at four different (10 ppm, 40 ppm, 60 ppm, and 80 ppm) metal ion concentrations. In general, the results of the remediation efficiency and partition coefficients obtained in this study are highly metal ion dependent and also dependent upon the chelator used for the remediation. Specifically, the remediation efficiency of the molecular micelles was found to be comparable to or better than the corresponding remediation efficiency obtained when SDS or EDTA was used for the remediation. However, at optimum conditions, poly-SULV and poly-L-SULA molecular micelle chelators demonstrated superior remediation efficiencies for Cr, with remediation efficiency of 99.9 ± 8.7% and 99.1 ± 0.7%, respectively.

关键词： Heavy metal Ion Remediation molecular micelles Chelator D-Optimum Experimental Design Kaolinite Clay

Incidence evaluation of <i>Crypticerya multicicatrices</i>and <i>maconellicoccus hirsutus</i>in Colombian Seaflower Biosphere Reserve

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Agricultural Sciences 2013年第12期4卷 654-665页

作者： marcela Silva-Gomez John A. Quiroz-Gamboa Francisco C. Yepes maría F. maya Adriana Santos Lilliana m. Hoyos-Carvajal Jardín Botánico de San Andrés Universidad Nacional de Colom-bia Sede Caribe San Andrés Colombia Universidad Nacional de Colombia Sede Medellín Medellín Colombia

An evaluation of the incidence of Crypticerya multicicatrices and maconellicoccus hirsutus in Colombian Seaflower Biosphere Reserve in San Andrés, Providence and Santa Catalina islands, from mid-August to mid-November 2012 was made. 38 locations were sampled, and 34% of sites tested show an incidence of C. multicicatrices oscillating between a range of 80%-100%, 24% with 40%-80% of incidence, 18% between 10%-40% and 24% with a range of 0%-10%. The occurrence of m. hirsutus fluctuated between 0.5% and 17%. There were seven genera of ants associated C. multicicatrices and 94 hosts of this agriculturally important insect and we found high incidence of associated sooty mold in C. multicicatrices hosts. Observations also contained some developmental stages of C. multicatrices.

关键词： Colombia’s Caribbean Insular Pink Hibiscus mealybug multicicatrices Fluted Scale Sap Sucking Insects Honey Dew Sooty mold

Pathogenicity and amino acid sequences of hemagglutinin cleavage site and neuraminidase stalk of differently passaged H9N2-avian influenza virus in broilers

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Advances in Bioscience and Biotechnology 2011年第4期2卷 198-206页

作者： Houssam A. Shaib Nelly Cochet Thierry Ribeiro Afif m. Abdel Nour Georges Nemer maya F. Saade Elie K. Barbour Department of Animal and Veterinary Sciences Faculty of Agricultural and Food Sciences American University of Beirut (AUB) P.O. Box 11-0236 Beirut Lebanon

Low pathogenic Avian Influenza (AI) virus has the ability to evolve to high pathogenic viruses resulting in significant economic losses in the poultry sector. This study aims at assessing the impact of H9N2 viral passaging in broilers and its relatedness to pathogenicity and amino acid (a.a) sequences of the hemagglutinin (HA) cleavage site and neuraminidase (NA) stalk. The original H9N2 AI virus (P0) was used to challenge ten-21 days old broilers. Individual recovery of H9N2 virus from homogenates of trachea, lungs and airsacs was attempted in 9 days old chicken embryos, as a conclusion of the first passage (P1). Tracheal isolates of H9N2 were passaged for a second (P2) and a third (P3) time in broilers, followed by a similar embryonic recovery procedure. The a.a. sequence of a part of HA1 cleavage site and Neuraminidase stalk were compared among the differently passaged viruses;an assessement of the relatedness of the determined a.a. sequences to the pathogenicity in broilers, based on frequency of mortality, morbidity signs, gross and microscopic lesions at 3 days post challenge with the P1, P2, and P3-H9N2, is concluded. An increase in certain morbidity signs and specific lesions was observed in P2- and P3-H9N2 challenged broilers compared to birds challenged with P1-H9N2. A conserved R-S-S-R amino acid sequence at the HA1 cleavage site was observed in the differently passaged H9N2, associated with a variability in the NA stalk-a.a sequences. The passaging of the low pathogenic H9N2 virus in broilers leads to a trend of increase in pathogenicity, manifested in higher frequency of morbidity signs, and of specific gross and microscopic lesions of the examined organs. This passaging was associated with a conserved a.a. sequence of the hemaglutinin cleavage site and a variability in the sequence of the neuraminidase stalk. A detailed study of the potential of the detected variability in the neuraminidase stalk of H9N2 in induction of a higher pathogenicity in broile

关键词： H9N2 Avian Influenza Pathogenicity Passaging Broilers Amino Acid Sequences Hemagglutinin (HA) Neuraminidase (NA) Stalk

Spin-Labelled 1-Ethyl-1-Nitrosourea Prevents Doxorubicin and Bleomycin-Induced Oxidative Stress in Lungs, Hearts and Kidneys of Tumour-Bearing mice

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Advances in Biological Chemistry 2014年第5期4卷 291-300页

作者： Veselina G. Gadjeva Galina D. Nikolova Boncho G. Grigorov Antoaneta m. Zheleva Anna N. Tolekova maya I. Vasileva Department of Chemistry and Biochemistry Faculty of Medicine Trakia University Stara Zagora Bulgaria Department of Physiology Pathophysiology and Pharmacology Faculty of Medicine Trakia University Stara Zagora Bulgaria Laboratory of Oncopharmacology National Cancer Institute Sofia Bulgaria

This study was carried out to determine the possible protective effect of 1-ethyl-3-[4-(2, 2, 6, 6-tetramethylpiperidine-1-oxyl)]-1-nitrosourea (SLENU), recently synthesised in our laboratory on doxorubicin and bleomycin-induced oxidative toxicity in C57 black tumour-bearing mice. Specifically, alterations in some biomarkers of oxidative stress, such as lipid peroxidation products measured as malondialdehyde (mDA) levels and activities of the antioxidant enzymes, superoxide dismutase (SOD) and catalase (CAT), were studied in lung, heart and kidney homogenates isolated from C57 black tumor-bearing mice after i.p. treatment with solutions of DOX (60 mg/kg) and BLm (60 mg/kg). The same biomarkers were also measured after i.p. pretreatment of mice with SLENU (100 mg/kg). After treatment with doxorubicin, heart and kidney homogenates of mice had significantly higher productions of lipid peroxidation compared to lung homogenates. It was accompanied by increased activity of the antioxidant defence enzyme superoxide dismutase and decreased activity of catalase. Bleomycin-induced oxidative stress was confirmed by significantly higher production of lipid peroxidation in lungs compared to heart homogenates, elevation of the anti-oxidant activity of superoxide dismutase and decreased activity of catalase enzymes. After pre-treatment of the mice with SLENU, the levels of all studied oxidative stress biomarkers were significantly improved in comparison with those of the mice treated alone with either bleomycin, or doxorubicin. The present results and those from a previously demonstrated superoxide scavenging activities (SSA) of the nitrosourea SLENU have enabled us to explain the protective effect of the spin-labelled nitrosourea on doxorubicin and bleomycin-induced oxidative stress by scavenging of??O2- and increased NO release.

关键词： Doxorubicin Bleomycin Spin-Labelled Superoxide Dismutase Catalase Lipid Peroxidation

An Alzheimer's Disease-Relevant Presenilin-1 mutation Augments Amyloid-Beta-Induced Oligodendrocyte Dysfunction

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神经损伤与功能重建 2011年第2期6卷 128-141页

作者： maya K.DESAI BRENDAN J.GUERCIO WADE C.NARROW WILLIAm J.BOWERS Department of Pharmacology and Physiology University of Rochester School of Medicine and DentistryRochesterNew York Center for Neural Development and Disease University of Rochester School of Medicine and DentistryRochesterNew York Department of microbiology and Immunology University of Rochester School of Medicine and DentistryRochesterNew York Department of Neurology University of Rochester School of Medicine and DentistryRochesterNew York

研究表明,家族性阿尔茨海默病(FAD)患者处于无症状或临床前阶段时,脑白质即出现病理改变。此种改变在髓鞘破坏及阿尔茨海默病(AD)病理生理中的作用有待进一步研究阐明。笔者前期研究证实,三重转基因AD小鼠(人淀粉前体蛋白基因的Swedish... 详细信息

研究表明,家族性阿尔茨海默病(FAD)患者处于无症状或临床前阶段时,脑白质即出现病理改变。此种改变在髓鞘破坏及阿尔茨海默病(AD)病理生理中的作用有待进一步研究阐明。笔者前期研究证实,三重转基因AD小鼠(人淀粉前体蛋白基因的Swedish突变,早老素-1 m146V(PS1m146V)敲入突变及tauP301L突变)表现出类似FAD患者的髓鞘破坏,Aβ1-42促进了白质病变。本研究离体实验证实,PS1m146V变异导致小鼠少突胶质前体细胞在分化过程中易出现类似Aβ1-42诱导的变化。PS1m146V的表达损伤少突胶质前体细胞的功能并影响髓鞘碱性蛋白的分布,暴露于Aβ1-42加重此影响。由PS1m146V及Aβ1-42导致的髓鞘破坏及髓鞘碱性蛋白在亚细胞结构中的误定位可被TWS119(糖原合成激酶(GSK)-3β抑制剂)抑制,提示GSK-3β激酶活动在此病理过程中有重要作用。综上所述,本研究有助于增加对AD早期无症状阶段,由PS1m146V及Aβ1-42导致少突胶质细胞功能异常及髓鞘损伤的机制的理解,并提供了针对少突胶质细胞预防AD相关白质病变的新的治疗靶点。

关键词：阿尔茨海默病白质髓磷脂少突胶质细胞髓鞘碱性蛋白淀粉β样蛋白早老素-1 3重转基因AD

Prevalence of mild T30, T3, and Severe VT Strains of Citrus tristeza Virus in Central-Northern Veracruz, mexico

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American Journal of Plant Sciences 2022年第4期13卷 494-505页

作者： Rosalba Contreras-maya Angel Villegas-monter Amalio Santacruz-Varela Nicacio Cruz-Huerta Laura D. Ortega-Arenas Daniel L. Ochoa-martinez Colegio de Postgraduados Texcoco Estado de México México

The presence and distribution of Citrus tristeza virus (CTV) strains on plants of four citrus species required analysis of plants showing small fruits, yellowing, and twig dieback. Typical citrus tristeza symptoms showed in citrus plantations in Veracruz, mexico, and caused gradual deterioration, low yield, and death of the plants. Seven citrus-growing municipalities in Central and Northern Veracruz presented the severe VT strain: the incidence in seven of the eight sampled municipalities ranged from 7% in Alamo to 50% in Tihuatlan. As for the T30 strain, its presence and distribution ranged from 17% in Tihuatlan to 83% in Cuitlahuac. Values for the T3 strain went from 20% in Castillo de Teayo to 50% in Papantla. In Tihuatlan, two samples were positive for the T36 strain. Only Citrus sinensis has historical recording infections by severe strains of CTV, unlike other important citrus species. The incidence of orchards quickly declining increases rapidly in Veracruz, the largest citrus producer in mexico. It becomes critical as the predominant and sensitive rootstock is sour orange (Citrus aurantium). It is important to note that the specific primers used could not be identified in 29% of the samples, suggesting that they could be other than T30, T3, VT, and T36 strains.

关键词： Citrus Incidence Strains Quick Decline Severity

Communication,Computation,and Governance:A multiscalar Vantage on the Prehispanic mesoamerican World

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Journal of Social Computing 2022年第1期3卷 91-118页

作者： Gary m.Feinman David m.Carballo the Negaunee Integrative Research Center Field Museum of Natural HistoryChicagoIL 60605USA Anthropology Archaeologyand Latin American StudiesBoston UniversityBostonMA 02215USA

Writing has often been put forth as one indicator of *** correspondence dovetails with the even broader cross-species expectation that the degrees of social complexity and levels of computational communication should closely *** in a general sense across human cooperative arrangements,a basic relationship between these variables undoubtedly exists,more detailed and fine-grained analyses indicate important axes of ***,our focus is on prehispanic mesoamerica and the means of computation and communication employed over more than three millennia(ca.1500 BCE-1520 CE).We take a multiscalar and diachronic analytical frame,in which we look at 30 central places,six macroregions,and mesoamerica as *** unraveling elements of“social complexity”,and decoupling computation from communication,we illustrate that institutional differences in governance had a marked effect on the specific modes and technologies through which prehispanic mesoamerican peoples communicated across time and *** and spatial scale,though relevant,do not alone determine time/space diversity in media of computational *** article is part of the theme issue“Evolution of Collective Computational Abilities of(Pre)Historic Societies”.

关键词： mesoamerica archaeology communication computation writing polity scale calendrics maya Aztec