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Precision silviculture:use of UAVs and comparison of deep learning models for the identification and segmentation of tree crowns in pine crops

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International Journal of Digital Earth 2022年第1期15卷 2223-2238页

作者： Manuel Ignacio Perez Bruno Karelovic roberto molina Rodrigo Saavedra Pierluigi Cerulo Guillermo Cabrera Department of Computer Sciences Universidad de Concepcion Biblioteca CentralConcepcionChile Celulosa Arauco y Constitucion SA I&DSantiagoChile

The monitoring of trees is crucial for the management of large areas of forest cultivations,but this process may be ***,remotely sensed data offers a solution to automate this *** this work,we used two neural network methods named You Only Look Once(YOLO)and Mask R-CNN to overcome the challenging tasks of counting,detecting,and segmenting high dimensional Red–Green–Blue(RGB)images taken from unmanned aerial vehicles(UAVs).We present a processing framework,which is suitable to generate accurate predictions for the aforementioned tasks using a reasonable amount of labeled *** compared our method using forest stands of different ages and *** counting,YOLO overestimates 8.5%of the detected trees on average,whereas Mask R-CNN overestimates a 4.7%of the *** the detection task,YOLO obtains a precision of 0.72 and a recall of 0.68 on average,while Mask R-CNN obtains a precision of 0.82 and a recall of *** segmentation,YOLO overestimates a 13.5%of the predicted area on average,whereas Mask R-CNN overestimates a 9.2%.The proposed methods present a cost-effective solution for forest monitoring using RGB images and have been successfully used to monitor∼146,500 acres of pine cultivations.

关键词： Artificial intelligence tree identification forestry remote sensing

Ex vivo antioxidant effects of D-004, a lipid extract from Roystonea regia fruits, on rat prostate tissue

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Asian Journal of Andrology 2008年第4期10卷 659-666页

作者： Yohani Perez Vivian molina Rosa Mas roberto Menendez Rosa M. Gonzailez Ambar Oyarzabal Sonia Jimenez Laboratory of Biochemistry Center of Natural Products National Center for Scientific Research Havana City 6990 Cuba

Aim： To investigate whether oral treatment with D-004, a lipid extract of the Cuban royal palm fruit, produces antioxidant effects in the prostate tissue of normal and testosterone （T）-treated rats. Methods： In our first experiment, normal rats were distributed into five groups： one group treated with the vehicle and four groups treated with D-004 （100, 200, 400 or 800 mg/kg）. In our second experiment, rats were randomized into five groups： a negative control group and four T-injected groups. The latter were comprised of a positive control group treated with the vehicle, and three groups treated with D-004 （200, 400 or 800 mg/kg）. Results： In normal rats, D-004 （100-800 mg/kg） inhibited significantly and dose-dependently iron-initiated malondialdehyde （MDA） accumulation in prostate homogenates （35.7%-80.0%） vs. the controls. D-004 （200-800 mg/kg） significantly reduced baseline MDA and carbonyl groups in prostate homogenates of normal rats to approximately 80% and 50%, respectively, and totally （100%） in T-treated rats. Conclusion： Oral treatment with D-004 reduced MDA and carbonyl groups dose-dependently and markedly in normal and T-injected rats. These findings show that D-004 given at doses effective to prevent prostate hyperplasia also produces antioxidant effects in the prostate tissue.

关键词： D-004 Roystonea regia Cuban royal palm prostate hyperplasia lipid peroxidation antioxidant

On the unsteady motion and stability of a heaving airfoil in ground effect

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Acta Mechanica Sinica 2011年第2期27卷 164-178页

作者： Juan molina David Angland School of Engineering Sciences University of Southampton Southampton SO17 1BJ UK

This study explores the fluid mechanics and force generation capabilities of an inverted heaving airfoil placed close to a moving ground using a URANS solver with the Spalart-Allmaras turbulence model. By varying the mean ground clearance and motion frequency of the airfoil, it was possible to construct a frequency-height diagram of the various forces acting on the airfoil. The ground was found to enhance the downforce and reduce the drag with respect to freestream. The unsteady motion induces hysteresis in the forces’ behaviour. At moderate ground clearance, the hysteresis increases with frequency and the airfoil loses energy to the flow, resulting in a stabilizing motion. By analogy with a pitching motion, the airfoil stalls in close proximity to the ground. At low frequencies, the motion is unstable and could lead to stall flutter. A stall flutter analysis was undertaken. At higher frequencies, inviscid effects overcome the large separation and the motion becomes stable. Forced trailing edge vortex shedding appears at high frequencies. The shedding mechanism seems to be independent of ground proximity. However, the wake is altered at low heights as a result of an interaction between the vortices and the ground.

关键词： Oscillating airfoil · Flutter · Wing in ground effect · Vortex shedding

Tracheal relaxation of five medicinal plants used in Mexico for the treatment of several diseases

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Asian Pacific Journal of Tropical Medicine 2014年第3期7卷 179-183页

作者： Amanda Snchez-Recillas Paul Mantecón-Reyes Patricia Castillo-Espaa Rafael Villalobos-molina Maximiliano Ibarra-Barajas Samuel Estrada-soto Facultad de Farmacia Universidad Autonoma del Estado de MorelosAvenida Universidad 1001.Col.ChamilpaCuernavacaMorelos 62209México Centro de Investigación en Riotecnología Universidad Autónoma del Estado de Morelos.Avenida Universidad 1001Col.ChamilpaCuernavacaMorelos 62209México Unidad de Biomedicina Facultad de Estudios Superiores IztacalaUniversidad Nacional Autónoma de MéxicoTlalnepantlaEstudo de Mexico 54090México

Objective:To assess the relaxant effect of several organic extracts obtained from Agastache mexicana(***),Cochlospermum vitifolium(***),Cordia morelosana(***),Lepechinia caulescens(***)and Talauma mexicana(71 mexicana)used in Mexican traditional medicine for the treatment of several ***:Extracts were obtained by maceration at room temperature using hexane,dicliloromethane and methanol for each plant *** organic extracts were evaluated ex vivo to determine their relaxant activity on the contractions induced by carbaehol(cholinergic receptor agonist,1μmol/L in isolated rat tracheal ***:A total of 15 extracts were evaluated(three for each species).All test samples showed significant relaxant effect,in a concentration-dependent manner,on the contractions induced by 1μmol/L carbachol,with exception of extracts from *** extracts were less potent than theophylline[phosphodiesterase inhibitor,EC_(50):(28.79±0.82)μg/mL]that was used as positive ***-response curves revealed that the extracts with more significant effects were dichloromethanic extracts of ***[E_(max):(103.03±3.32)%and EC_(50):(159.39±3.72)μg/mL)and ***[Emax:(106.58±2.42)%and EC_(50):(219.54±7.61)μg/mL].Finally,hexanic and dichloromethanic extracts from *** were fully effective but less potent than ***,and ***:Less polar extracts obtained from ***,71 mexicana and *** exhibited greater relaxant effect on tracheal rat rings,which allows us to suggest them as sources for the isolation of bioactive molecules with potential therapeutic value in the treatment of asthma.

关键词： Asthma Mexican medicinal plants Trachea Relaxant effect

Effectiveness of a microabrasion technique using 16% HCL with manual application on fluorotic teeth: A series of studies

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World Journal of Clinical Cases 2020年第4期8卷 743-756页

作者： Martina Nevárez-Rascón Nelly molina-Frechero Edith Adame Ethel Almeida Uriel soto-Barreras Enrique Gaona Alfredo Nevárez-Rascón Facultad de Odontología Maestría en EstomatologíaUniversidad Autónoma de ChihuahuaChihuahua 31000México División de Ciencias Biológicas y de la Salud Universidad Autónoma MetropolitanaXochimilco 04960México

BACKGROUND Dental fluorosis is caused by excessive fluoride ingestion during tooth *** a consequence,there is a higher porosity on the enamel surface,which causes an opaque *** The aim of this study was to identify a dental intervention to improve the smile in patients with tooth *** aims were to relate the stain size on fluorotic teeth with the effectiveness of stain removal,enamel loss and procedure time using a manual microabrasion technique with 16%hydrochloric acid(HCL).METHODS An experimental study was carried out on 84 fluorotic teeth in 57 adolescent patients,33 females and 24 males,with moderate to severe *** means,standard deviations and percentages were analyzed using nonparametric statistics and ArchiCAD 15 software was used for the variables including stain size and effectiveness of stain *** The average enamel loss was 234μm and was significantly related to the procedure time categorized as 1-4 min and 4.01-6 min,resulting in a P>*** microabrasion technique using 16%HCL was effective in 90.6%of patients and was applied manually on superficial stains in moderate and severe *** time was less than 6 min and enamel loss was within the acceptable *** Microabrasion is a first-line treatment;however,the clinician should measure the average enamel loss to ensure that it is within the approximate range of 250μm in order to avoid restorative treatment.

关键词： Microabrasion of the enamel Dental fluorosis Enamel stains Fluorotic teeth Hydrochloric acid 16% Stain removal

Clinical Profiles at the Time of Diagnosis of SARS-CoV-2 Infection in Costa Rica During the Pre-vaccination Period Using a Machine Learning Approach

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Phenomics 2022年第5期2卷 312-322页

作者： Jose Arturo molina-Mora Alejandra González Sergio Jiménez-Morgan Estela Cordero-Laurent Hebleen Brenes Claudio soto-Garita Jorge Sequeira-soto Francisco Duarte-Martínez Centro de Investigación en Enfermedades Tropicales(CIET)and Facultad de Microbiología Universidad de Costa RicaSan José2060Costa Rica Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud(INCIENSA) Tres Ríos 30301Costa Rica Escuela de Medicina Universidad de Costa RicaSan José2060Costa Rica

The clinical manifestations of COVID-19,caused by the SARS-CoV-2,define a large spectrum of symptoms that are mainly dependent on the human host *** Costa Rica,more than 169,000 cases and 2185 deaths were reported during the year 2020,the pre-vaccination *** describe the clinical presentations at the time of diagnosis of SARS-CoV-2 infection in Costa Rica during the pre-vaccination period,we implemented a symptom-based clustering using machine learning to identify clusters or clinical profiles at the population level among 18,974 records of positive *** were compared based on symptoms,risk factors,viral load,and genomic features of the SARS-CoV-2 sequence.A total of 18 symptoms at time of diagnosis of SARS-CoV-2 infection were reported with a frequency>1%,and those were used to identify seven clinical profiles with a specific composition of clinical *** the comparison between clusters,a lower viral load was found for the asymptomatic group,while the risk factors and the SARS-CoV-2 genomic features were distributed among all the *** other distribution patterns were found for age,sex,vital status,and *** conclusion,during the pre-vaccination time in Costa Rica,the symptoms at the time of diagnosis of SARS-CoV-2 infection were described in clinical *** host co-morbidities and the SARS-CoV-2 genotypes are not specific of a particular profile,rather they are present in all the groups,including asymptomatic *** addition,this information can be used for decision-making by the local healthcare institutions(first point of contact with health professionals,case definition,or infrastructure).In further analyses,these results will be compared against the profiles of cases during the vaccination period.

关键词： COVID-19 Costa Rica Machine learning Diagnosis SARS-CoV-2 Clinical profiles

Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

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Frontiers in Energy 2019年第3期13卷 522-538页

作者： Pedro PONCE Therese PEFFER Arturo molina Tecnologico de Monterrey calle del puente 222 MexicoMexico CityNon-US/Non-Canadian 64849Mexico California Institute for Energy and Environment University of California BerkeleyBerkeleyCA 94720USA

It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes;thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats perceptions beliefs signal detection theory (SDT) fuzzy signal detection theory (FSDT) chi-square (CS) test

Systemic analysis of metabolome reconfiguration in Arabidopsis after abiotic stressors uncovers metabolites that modulate defense against pathogens

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Plant Communications 2024年第1期5卷 55-68页

作者： Antoni Garcia-molina Victoria Pastor Centre for Research in Agricultural Genomics(CRAG)CSIC-IRTA-UAB-UB C/Vall MorontaEdifici CRAG08193 Bellaterra(Cerdanyola del Valles)BarcelonaSpain Department of Biology Biochemistryand Natural SciencesSchool of Technology and Experimental SciencesUniversitat Jaume I12006 Castellode la PlanaSpain

Understanding plant immune responses is complex because of the high interdependence among biological processes in homeostatic ***,the integration of environmental cues causes network rewiring that interferes with defense ***,plants retain molecular signatures configured under abiotic stress periods to rapidly respond to recurrent stress,and these can alter *** changes imposed by abiotic stressors are persistent,although their impact on defense remains to be *** this study,we profiled metabolomes of Arabidopsis plants under several abiotic stress treatments applied individually or simultaneously to capture temporal trajectories in metabolite composition during adverse conditions and *** systemic analysis was performed to address the relevance of me-tabolome changes and extract central features to be tested in *** results demonstrate irreversibility in major fractions of metabolome changes as a general pattern in response to abiotic stress ***-tionalanalysisofmetabolomesandco-abundancenetworkspoints toconvergence inthereconfigurationof organic acid and secondary metabolite *** mutant lines for components related to these metabolic pathways showed altered defense capacities against different ***,our data suggest that sustained metabolome changes configured in adverse environments can act as mod-ulators of immune responses and provide evidence for a new layer of regulation in plant defense.

关键词： abiotic stress Arabidopsis biotic stress combinatorial stress metabolomics systems biology

Grounded theory qualitative approach from Foucault's ethical perspective:Deconstruction of patient self-determination in the clinical setting

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World Journal of Clinical Cases 2021年第28期9卷 8312-8326页

作者： Jesús molina-Mula Nursing and Physiotherapy Department University of Balearics IslandPalma 07122Illes BalearsSpain

This paper aims to explain the construction of the autonomous subject from Foucault's ethical perspective for the qualitative analysis of interprofessional relationships,patient-professional relationships,and moral ethics *** tried to break loose from the self,which is merely the result of a biopol-itical subjectivation and constituted an interpersonal *** this,different elements involved in the decision-making capacity of patients in a clinical setting were ***,the context in which decision-making occurs has been explained,distinguishing between traditional practices involved in self-care and the more modern conceptions that make certain possible ***,an attempt is made to explain the formation of the medicalisation of society using the transformations of what Foucault called"techniques of the self".Finally,the ethical framework for a subject's"self-creation",insisting more on the exercises of self-subjectivation,reinforcing the ethics of the self by itself,the"care of the self",has been *** role of the patient is understood as an autonomous subject to the extent that the clinical institution and the professionals involved comprehend how the patient’s autonomy in the clinical environment is *** these elements could generate grounded theory on the qualitative methodology of this *** current ethical model based on universal principles is not useful to provide a capacity for patients decision-making,relegating to the background their opinions and ***,a new ethical perspective emerges that aims to return the patient to the fundamental axis of attention.

关键词： Decision making Personal autonomy Foucault Principle-based Ethics Bioethics,Qualitative methodology,Grounded theory