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Bio-Functional Nanodiamond Restorative Materials Containing Bio-Additives: In Vitro Approach

Open Journal of Stomatology 2015年第5期5卷 117-126页

作者： Victoria Tamara Perchyonok Tatiana Souza Rafael Felliti Shengmiao Zhang Sias Grobler VTPCHEM PTY LTD Southport Australia S3 Logan Australia colonia 1181 apt 302 Montevideo Uruguay School of Material Science and Engineering East China University of Science and Technology Shanghai China Oral and Dental Research Institute Faculty of Dentistry University of the Western Cape Cape Town South Africa

Restorative materials in the new era aim to be “bio-active”, bio-functional and long-lasting. As a part of our continuous interest of developing functional dual action restorative materials capable of being “bio-active” functional restorative materials, we designed and evaluated several novel nano-diamond:chitosan containing hydrogels as a prototype of molecular scaffold materials capable of free radical defense action containing propolis extract (antioxidant containing material) from 3 different regions namely, Green Brazilian Propolis, Uruguan Propolis and Australian Propolis. We evaluated the physical properties, bonding to dentin as well as test the bioadhesion of the newly designed materials in order to access the suitability of these prototype materials as suitable restorative materials, evaluated total phenol capacity of the materials as well as free radical defense capacity using BSA protein model as a quick and effective in vitro model. The hydrogels were prepared as previously reported by our protocol. The physico-chemical features including surface morphology (SEM), release behaviors, stability of the antioxidant-chitosan-nanodiamond and the effect of the hydrogels on the shear bond strength of dentin were measured. Structural investigations of the reactive surface of the hydrogel are reported. Bio-adhesive studies were performed in order to assess the suitability of these designer materials. Free radical defence and performance of the materials was evaluated using BSA and Folin Ciocalteu assay. Results: Within the limitations of the study design chitosan-antioxidant hydrogels are suitable materials for functional restorative and periodontal applications in vitro. The addition of propolis extracts nano-diamond chitosan prototype delivery system had a beneficial effect on the design of the hydrogel by increasing bioadhesive properties of the newly prepared hydrogels, increasing free radical defense properties of the biomaterials as well as increasing the d

关键词： Therapeutic Polymers Adhesives Chitosan Hydrogels Propolis Melatonin Naproxen Antimicrobial Dentin Bonding Antioxidants Bioactive

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Real-time ore sorting using color and texture analysis

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International Journal of Mining Science and Technology 2023年第6期33卷 659-674页

作者： David G.Shatwell Victor Murray Augusto Barton Hochschild Mining PLC La Colonia 180Lima 15023Peru Department of Electrical Engineering Universidad de Ingenieria y Tecnologia-UTECLima 15063Peru John A.Paulson School of Engineering and Applied Sciences Harvard UniversityCambridge 02134USA Department of Electrical and Computer Engineering University of New MexicoAlbuquerque 87131USA

Sensor-based ore sorting is a technology used to classify high-grade mineralized rocks from low-grade waste rocks to reduce operation *** ore-sorting algorithms using color images have been proposed in the past,but only some validate their results using mineral grades or optimize the algorithms to classify rocks in *** paper presents an ore-sorting algorithm based on image processing and machine learning that is able to classify rocks from a gold and silver mine based on their *** algorithm is composed of four main stages:(1)image segmentation and partition,(2)color and texture feature extraction,(3)sub-image classification using neural networks,and(4)a voting system to determine the overall class of the *** algorithm was trained using images of rocks that a geologist manually classified according to their mineral content and then was validated using a different set of rocks analyzed in a laboratory to determine their gold and silver *** proposed method achieved a Matthews correlation coefficient of 0.961 points,higher than other classification algorithms based on support vector machines and convolutional neural networks,and a processing time under 44 ms,promising for real-time ore sorting applications.

关键词： Ore sorting Image color analysis Image texture analysis Machine learning

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Food allergy among Mexican infants and preschoolers:prevalence and associated factors

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World Journal of Pediatrics 2023年第4期19卷 401-405页

作者： Martín Bedolla-Barajas Jaime Morales-Romero Rafael Sánchez-Magallón Jorge Alejandro Valdez-Soto Tonatiuh Ramses Bedolla-Pulido Carlos Meza-López Allergy and Immunology Department Nuevo Hospital Civil de Guadalajara Dr.Juan I.MenchacaSalvador Quevedo y Zubieta No.740Colonia La Perla44340GuadalajaraJaliscoMéxico Institute of Public Health Universidad VeracruzanaXalapaMexico Pediatrics Department Nuevo Hospital Civil de Guadalajara Dr.Juan I.MenchacaGuadalajaraMexico

The number of people with food allergy(FA)has increased in recent decades,as has the number of foods to which they are *** of FA prevalence vary widely,likely because of different definitions,evaluated foods and geo-graphic *** developed countries,overall preva-lence estimates range from 1.9%to 7.2%[1,2].In Latin America,the prevalence of FA in children is between 1.4%and 5.3%[3-6],with important age-based variations(from 1.9%in infants to 0.4%in preschoolers)[7].FA is a complex trait in which the interplay of genetic and environmental fac-tors results in disease ***-known factors that increase atopic susceptibility include sex[8,9],age[10],and socioeconomic status[11-13].Furthermore,the asso-ciation between family history of allergies and childhood FA has been consistently reported in recent ***,a maternal history of allergic disease appears to be more strongly associated with FA than paternal history of atopy[14].

关键词： prevalence allergy allergic

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Experimental approaches to select tree species for forest restoration:effects of light,water availability and interspecific competition in degraded areas

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Journal of Forestry Research 2022年第4期33卷 1197-1207页

作者： Johanna Croce Ernesto I.Badano Carolina B.Trigo Fernanda Martinez-Galvez Andrés Tálamo Laboratorio de Ecología Aplicada a la Conservación Instituto de Bio y Geociencias del Noroeste ArgentinoConsejo de Investigaciones Científi cas y Técnicas-Universidad Nacional de SaltaAvenida Bolivia 51504400 SaltaArgentina IPICYT/División de Ciencias Ambientales Instituto Potosino de Investigación Científi ca y TecnológicaCamino a la Presa San José2055Colonia Lomas 4^(a)Sección78216 San Luis PotosíMéxico

Knowing what native trees can recr uit on degraded areas allows selecting the best species to restore these ***,as this information is not often available,experimentation is required before large-scale *** study used ex situ experiments to make these decisions on *** with r-strategist plants,excessive solar radiation and water shortage commonly impair tree recruitment in open *** experiments focused on the interactions among these factors and were conducted with three pioneer species from seasonally dry forests of northwest Argentina,Anadenanthera colubrina,Ceiba chodatii and Jacaranda *** of each species were sown at two light levels(sunlight/shade),two rainfall levels(full/reduced)and two levels of interspecific competition(with/without competitor)in a tree *** emergence and survival were monitored over a year and the results indicate that species differentially respond to varying levels of light and *** of *** tolerated water shortages under elevated solar radiation,which are desirable features for forest *** of *** tolerated shade and drought,suggesting that they require shading for establishing in open ***,*** seedlings neither tolerated full sunlight nor water shortages,suggesting that this species requires shading and regular watering if used in *** of the effects of light and water,the survival of all species was reduced by interspecific *** results highlight the importance of experimentation for selecting the best species for forest restoration and can enhance the cost/benefit ratios of these actions.

关键词： Common-garden experiments Drought Ecological restoration Interspecific competition Seedling survival Shade

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Demographic and behavioral responses of the White-winged Dove to human disturbances during winter in northwestern Mexico

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Avian Research 2022年第4期13卷 437-444页

作者： Ruben Ortega-Alvarez Jovani Le on-Aguilar Antonio Isain Contreras-Rodríguez Gustavo Casta neda de los Santos Instituto de Investigaciones en Ecosistemas y Sustentabilidad(IIES)-Universidad Nacional Autonoma de Mexico Campus MoreliaAntigua Carretera a Patzcuaro 8711Col.San Jose de la HuertaMoreliaMichoacan58190Mexico Programa de Aves Urbanas(PAU) Los MochisSinaloaMexico Quirino Mendoza#320 Colonia del CarmenXochimilcoCiudad de Mexico16720Mexico Departamento de Educacion Ambiental Jardín Bot anico Benjamin Francis JohnstonSinaloaMexico

The simultaneous study of demography and behavior might provide a more comprehensive understanding about animal responses to anthropogenic *** White-winged Dove(Zenaida asiatica)is a frequent dweller of urban and agricultural habitats in North America,Central America,and the ***,research on the species is heavily biased to the *** analyzed the response of the species to human disturbances during winter across an urban-agricultural landscape in northwestern Mexico through a demographic and behavioral *** modeled the effect of disturbance types(pedestrians,cars,pavement and building cover)on the density of the ***,we investigated if surveillance behavior varied across the landscape by estimating and comparing perching proportion among land uses(urban grey areas,urban green areas,cropfields,shrublands).We did not detect the species within cropfields,possibly because food resources were not available for the dove during winter in this land *** cover limited species’density,as it might reduce the surface of the preferred feeding substrates of the *** and building cover increased the density of the species,as they might provide food and shelter for the dove,*** behavior peaked in urban grey areas,whereas it dropped in urban green *** on threat levels,threat type,and protective cover among land uses might in-fluence such behavioral *** approach contributes to the knowledge of the species and demonstrates that both demographic and behavioral cues provide complementary evidence for analyzing the impact of human disturbances on animals.

关键词： Agriculture Density Perch Sinaloa Urbanization Zenaida asiatica

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Reactivity of Indoles through the Eyes of a Charge-Transfer Partitioning Analysis

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物理化学学报 2018年第6期34卷 692-698页

作者： OROZCO-VALENCIA Ulises GáZQUEZ José L. VELA Alberto Departamento de Quimica Centro de Investigacion y de Estudios Avanzados Av. Instituto Politecnico Nacional 2508 Colonia San Pedro Zacatenco Ciudad de Mexico 07360 Mexico. Departamento de Quimica Universidad Autonoma Metropolitana-Iztapalapa

A global and local charge transfer partitioning model,based on the cornerstone theory developed by Robert *** and Robert ***,which introduces two charge transfer channels(one for accepting electrons(electrophilic) and another for donating(nucleophilic)),is applied to the reaction of a set of indoles with 4,*** global analysis indicates that the prevalent electron transfer mechanism in the reaction is a nucleophilic one on the indoles,i.e.,the indoles under consideration transfer electrons to 4,*** the reactivity descriptorswith exchange-correlation functionals including exact exchange(global hybrids) yields slightly better correlations than those obtained with generalized gradient-approximated functionals;however,the trends are *** the trend obtained with the number of electrons donated by the indoles,and predicted by the partitioning model,with that observed experimentally based on the measured rate constants,we propose that the number of electrons transferred through this channel can be used as a nucleophilicity scale to order the reactivity of indoles towards 4,*** approach to obtain reactivity scales has the advantage of depending on the intrinsic properties of the two reacting species;therefore,it opens the possibility that the same group of molecules may show different reactivity trends depending on the species with which they are *** local model allows systematic incorporation of the reactive atoms based on the their decreasing condensed Fukui functions,and the correlations obtained by increasing the number of reactive atoms participating in the local analysis of the transferred nucleophilic charge improve,reaching an optimal correlation,which in the present case indicates keeping three atoms from the indoles and two from 4,*** atoms selected by this procedure provide valuable information about the local reactivity of the indoles.W

关键词： Chemical reactivity Conceptual DFT Charge transfer Nucleophilicity Indoles Transition state prediction

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Landscape genetics reveals inbreeding and genetic bottlenecks in the extremely rare short-globose cacti Mammillaria pectinifera (Cactaceae) as a result of habitat fragmentation

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Plant Diversity 2017年第1期39卷 13-19页

作者： Reyna Maya-Garcia Santiago Arizaga Pablo Cuevas-Reyes Juan Manuel Penaloza-Ramirez Victor Rocha Ramirez Ken Oyama Facultad de Biologia Universidad Michoacana de San Nicolas de Hidalgo Mexico Escuela Nacional-de Estudios Superiores Unidad Morelia UNAM Antigua Carretera a Pdtzcuaro 8701 Colonia Ex-Hacienda de SanJose de la Huerta58190 Morelia Michoacan Mexico

Mammillaria pectinifera is an endemic, short-globose cactus species, included in the IUCN list as a threatened species with only 18 remaining populations in the Tehuacán-Cuicatlán Valley in central Mexico. We evaluated the population genetic diversity and structure, connectivity, recent bottlenecks and population size, using nuclear microsatellites. M. pectinifera showed high genetic diversity but some evidence of heterozygote deficiency(F_(IS)), recent bottlenecks in some populations and reductions in population size. Also, we found low population genetic differentiation and high values of connectivity for M. pectinifera, as the result of historical events of gene flow through pollen and seed dispersal.M. pectinifera occurs in sites with some degree of disturbance leading to the isolation of its populations and decreasing the levels of gene flow among them. Excessive deforestation also changes the original vegetation damaging the natural habitats. This species will become extinct if it is not properly ***, this species has some ecological features that make them more vulnerable to disturbance such as a very low growth rates and long life cycles. We suggest in situ conservation to prevent the decrease of population sizes and loss of genetic diversity in the natural protected areas such as the Tehuacán-Cuicatlán Biosphere Reserve. In addition, a long-term ex situ conservation program is need to construct seed banks, and optimize seed germination and plant establishment protocols that restore disturbed habitats. Furthermore, creating a supply of living plants for trade is critical to avoid further extraction of plants from nature.

关键词： Mammillaria pectinifera Nuclear SSR Genetic diversity Recent bottlenecks Effective population size

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Toxicity of Mexican native plant extracts against larvae of Aedes aegypti(Diptera: Culicidae)

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Asian Pacific Journal of Tropical Biomedicine 2015年第4期5卷 287-291页

作者： Rosario Ruiz-Guerrero Mario Alberto Rodríguez-Pérez Mariano Norzagaray-Campos CIITEC-IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco Centro de Biotecnología Genómica-IPN Blvd. Del Maestro S/N Colonia Narciso Mendoza CIIDIR-IPN-Sinaloa Bulevar Juan de Dios Bátiz Paredes No 250 Colonia San Joachin. Guasave

Objective: To evaluate five indigenous Mexican plants [Hippocratea excelsa, Hippocratea celastroides, Argemone mexicana(A. mexicana), Tagetes lucida, and Pseudosmodingium perniciosum(P. perniciosum)] toxicity against the fourth instar larvae of the dengue primary vector, Aedes aegypti(A. aegypti).Methods: Each plant part was treated successively with hexane, ethyl acetate, acetone, and methanol to extract potential active components of the plants against the dengue ***: There was a range of toxicity at 24 or 48 h post-exposure for the different plant parts and organic solvent used(LC50 values ranged between 20 and 890 μg/mL). Extracts from seeds of A. mexicana(hexane washing with methanol and acetone) and stem-bark of P. perniciosum(hexane) showed highest toxicity to Ae. aegypti larvae at 48 h post-exposure(LC50 values were80, 50, and 20 μg/mL, respectively), thus making them potential candidates as *** are on-going to characterize the bioactive components of the extracts, through chromatography, for their use as biological tools for the control of the primary dengue ***: A. mexicana and P. perniciosum are good candidates to combat the dengue vector, Ae. aegypti, as they were highly toxic to the larvae.

关键词： Aedes aegypti Dengue Larvicidal activity Plant organic extracts

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Experimental demonstration of full-field quantum optical coherence tomography

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Photonics Research 2020年第1期8卷 51-56页

作者： ZEFERINO IBARRA-BORJA CARLOS SEVILLA-GUTIéRREZ ROBERTO RAMíREZ-ALARCóN HECTOR CRUZ-RAMíREZ ALFRED B.U'REN Centro de Investigaciones en Optica A.C. Lomadel Bosque 115Colonia Lomas del Campestre37150 LeonGuanajuatoMexico 2lnstituto de Ciencias NuclearesUniversidad Nacional Autonomade MexicoApartado Postal 70-54304510 DFMexico

We present,to the best of our knowledge,the first implementation of full-field quantum optical coherence tomography(FF-QOCT).In our system,we are able to obtain full three-dimensional(3D)information about the internal structure of a sample under study by relying on transversely resolved Hong–Ou–Mandel(HOM)interferometry with the help of an intensified CCD(ICCD)*** system requires a single axial scan,obtaining full-field transverse single-photon intensity in coincidence with the detection of the sibling photon for each value of the signal-idler temporal *** believe that this capability constitutes a significant step forward toward the implementation of QOCT as a practical biomedical imaging technique.

关键词： technique. quantum system

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Study of wind towers with different funnels attached to in crease natural ventilation in an underground building

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Frontiers of Architectural Research 2020年第4期9卷 925-939页

作者： C.A.Varela-Boydo S.L.Moya R.Watkins Tecnologico Nocional de Mexico Centro Nacional de Investisacion y Desorrollo TecnoldsicoInterior Internado Palmira s/nColonia PalmiraCuernavaca62490 MorelosMexico Kent School of Architecture&Planning University of KentUK

Finding ways to cool buildings by natural,passive techniques is crucial in the context of global *** centuries,wind towers(traditi onal win dcatchers)have been used in the Middle East for cooling *** this study,the use of funnels at the openings of wind towers for wind ingress and egress is proposed primarily to increase the mass flow captured by the wind *** use of funnels in the wind in gress openings in creases the inlet area,improving the capture of *** parallel,the use of funnels in the egress openings modifies the wake of the tower,which aims to ease the exit of the flow from inside the *** design configurations are presented,where the length and width of the funnels are changed and tested separately by computational fluid dynamics(CFD).Results of over 120 CFD simulations are presented and *** volumetric flow entering the wind towers in creases by 10.7% in several *** results in dicate that adding funnels to wind towers could positively in fluence their *** the dimensions of the funnels affects their efficacy and can increase or decrease the airflow entering the tower.

关键词： Wind towers Passive cooling Natural ventilation Funnels CFD Wind catchers

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