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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

Role of dup A in virulence of Helicobacter pylori

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World Journal of Gastroenterology 2016年第46期22卷 10118-10123页

作者： Amin Talebi Bezmin Abadi guillermo perez-perez Department of Bacteriology Faculty of Medical Sciences Tarbiat Modares University Departments of Medicine and Microbiology New York University School of Medicine and VA Medical Center

Helicobacter pylori(H. pylori) is a gastric human pathogen associated with acute and chronic gastritis, 70% of all gastric ulcers, 85% of all duodenal ulcers, and both forms of stomach cancer, mucosal-associated lymphoid tissue(MALT) lymphoma and adenocarcinoma. Recently, attention has focused on possible relationship between presence of certain virulence factor and H. pylori-associated diseases. Some contradictory data between this bacterium and related disorders has been observed since not all the colonized individuals develop to severe disease. The reported diseases plausibility related to H. pylori specific virulence factors became an interesting story about this organism. Although a number of putative virulence factors have been identified including cytotoxin-associated gene a(cag A) and vac A, there are conflicting data about their actual participation as specific risk factor for H. pylori-related diseases. Duodenal ulcer promoting gene a(dup A) is a virulence factor of H. pylori that is highly associated with duodenal ulcer development and reduced risk of gastric cancer. The prevalence of dup A in H. pylori strains isolated from western countries is relatively higher than in H. pylori strains from Asian countries. Current confusing epidemiological reports will continue unless future sophisticated and molecular studies provide data on functional and complete dup A cluster in H. pylori infected individuals. This paper elucidates available knowledge concerning role of dup A in virulence of H. pylori after a decade of its discovery.

关键词： Helicobacter pylori dupA 细菌的毒力感染临床的结果

Memory for location and visual cues in white-eared hummingbirds Hylocharis leucotis

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Current Zoology 2011年第4期57卷 468-476页

作者： guillermo perez Carlos LARA Jose VICCON-PALE Martha SIGNORET-POILLON Doctorado en Ciencias Biologicas Universidad Autonoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 Moxico D.F. Moxico Laboratorio de Ecologfa de la Conducta Centro Tlaxcala de Biologfa de la Conducta UAT-UNAM Km 1.5 carretera Tlaxcala- Puebla s/n Colonia Xicohtoncatl Apdo. Postal 262 Tlaxcala Tlaxcala 90070 Moxico. Departamento el Hombre y su Ambiente. Universidad Autdnoma Metropolitana. Unidad Xochimilco. Calzada del Hueso 1100 Col. Villa Quietud 04960 MExico D.F. Mexico

In nature hummingbirds face floral resources whose availability, quality and quantity can vary spatially and temporally. Thus, they must constantly make foraging decisions about which patches, plants and flowers to visit, partly as a function of the nectar reward. The uncertainty of these decisions would possibly be reduced if an individual could remember locations or use visual cues to avoid revisiting recently depleted flowers. In the present study, we carried out field experiments with white-eared hummingbirds Hylocharis leucotis, to evaluate their use of locations or visual cues when foraging on natural flowers Penstemon roseus. We evaluated the use of spatial memory by observing birds while they were foraging between two plants and within a single plant. Our results showed that hummingbirds prefer to use location when foraging in two plants, but they also use visual cues to efficiently locate unvisited rewarded flowers when they feed on a single plant. However, in absence of visual cues, in both experiments birds mainly used the location of previously visited flowers to make subsequent visits. Our data suggest that hummingbirds are capable of learning and employing this flexibility depending on the faced environmental conditions and the information acquired in previous visits [Current Zoology 57 (4): 468–476, 2011].

关键词：视觉蜂鸟位置内存植物饲料花卉资源不确定性田间试验

Neurological manifestations with jugular vein thrombosis linked to an inflammatory profile may be a sequela of long COVID

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Neuroprotection 2023年第2期1卷 170-175页

作者： Elizabeth Mendoza-portillo Estefania Aleman-Navarro G.Aleph Prieto Yvonne Rosenstein Jose J.Lozano-Nuevo Araceli perez-Lopez Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suarez Ciudad de MéxicoMéxico Instituto de Biotecnología Universidad Nacional Autónoma de México(UNAM)CuernavacaMorelosMéxico Instituto de Neurobiología UNAM-JuriquillaQuerétaroMéxico Institute for Memory Impairments and Neurological Disorders University of California-IrvineIrvineCaliforniaUSA Hospital General de Ticomán Secretaría de Salud de la Ciudad de MéxicoCiudad de MéxicoMéxico Unidad de Investigación en Biomedicina Facultad de Estudios Superiores IztacalaUNAMTlalneplantlaEstado de MéxicoMéxico

More than 670 million cases of coronavirus disease 2019(COVID-19)have been recorded worldwide in the 3 years since the start of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)*** 45%of survivors of COVID-19 develop a syndrome known as long-term COVID,in which symptoms persist even months after the acute *** 76%of patients with long COVID experience neurological ***,patients who have survived COVID-19 have an increased risk of cerebral venous *** case report describes a 41-year-old woman who developed neurological manifestations associated with jugular vein thrombosis 24 h after administration of the Oxford–AstraZeneca(ChAdOx1 nCoV-19)vaccine(AstraZeneca-Serum Institute of India).She had been infected with SARS-CoV-2 three months before *** initially suspected to be a case of vaccine-induced immune thrombotic thrombocytopenia(VITT)in view of her recent vaccination,the patient did not have any hallmarks of VITT,such as thrombocytopenia,an increased D-dimer level,or antibodies against platelet ***,the neurological manifestations were associated with a high concentration of inflammatory cytokines,including interleukin(IL)-6,IL-17A,and IL-21,and elevated neutrophil levels in cerebrospinal fluid,suggesting that inflammatory immune components had a role in the development of thrombotic events and pointing to an alternative *** this case,the laboratory results indicated that the neurological manifestations associated with jugular vein thrombosis were not associated with ***,we propose that the thrombosis of the left jugular vein was a sequela of SARS-CoV-2 infection.

关键词： cerebral venous thrombosis long COVID vaccine

Factors associated with H pylori epidemiology in symptomatic children in Buenos Aires,Argentina

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World Journal of Gastroenterology 2006年第33期12卷 5384-5388页

作者： Cinthia Goldman Andrés Barrado Mariana Janjetic Norma Balcarce Eduardo Cueto Rua Masaru Oshiro María L Calcagno Margarita Martinez Sarrasague Julián Fuda Ricardo Weill Marcela Zubillaga guillermo I perez-perez José Boccio Radioisotopes Laboratory and Laboratory of Stable Isotopes Applied to Biology and Medicine Physics Department School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina Laboratory of Stable Isotopes Applied to Biology and Medicine Physics Department School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina Gastroenterology Unit Hospital de nios "Superiora Sor María Ludovica" La Plata Argentina Health Center Di Matteo San Fernando Buenos Aires Argentina Mathematics Department School of Pharmacy and Biochemistry University of Buenos Aires Buenos Aires Argentina Agrarian Industries Department School of Agronomy University of Morón Buenos Aires Argentina Departments of Medicine and Microbiology New York University School of Medicine New York United States

AIM: To determine prevalence of H pylori infection in symptomatic children in Buenos Aires, Argentina, and to investigate factors associated with H pylori positivity. METHODS: A total of 395 children with upper gastrointestinal symptoms referred to the Gastroente-rology Unit of the Children Hospital “Sor Maria Ludovica” were evaluated for the presence of H pylori by the 13C-Urea Breath Test (13C-UBT). A questionnaire was applied to the recruited ***: Prevalence of H pylori infection was 40.0%in this population (mean age 9.97 ± 3.1 years). The factors associated with H pylori positivity were number of siblings (P < 0.001), presence of pet cats (P = 0.03) and birds (P = 0.04) in the household, and antecedents of gastritis among family members (P = 0.01). After multivariate analysis, number of siblings [Odds ratio (OR) = 1.39; 95% CI, 1.20-1.61] and contact with pet cats (OR = 1.76; 95% CI, 1.00-3.09) remained as variables associated with H pylori infection. CONCLUSION: The prevalence of H pylori infection in children with upper gastrointestinal symptoms in Argentina was similar to that reported in developed countries. Children from families with a higher crowding index and presence of pet cats have a higher risk of being colonized with H pylori.

关键词：流行病学幽门螺杆菌甲酮-钠除草剂阿根庭

Progress in Use of Natural Products and Their Active Components against Helicobacter pylori

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Advances in Microbiology 2016年第14期6卷 1091-1129页

作者： Alejandro Venegas Jorge Hantar Touma Jessica Bravo guillermo perez-perez Centro de Investigación Biomédica Facultad de Medicina Universidad Diego Portales Santiago Chile Departments of Medicine and Microbiology New York Langone Medical Center NYU New York USA

Helicobacter pylori is considered the main etiological agent of gastritis, ulcers, and gastric carcinoma. It colonizes human gastric mucosa quite efficiently. Fifty % of the world population is actually infected. Since H. pylori discovery in 1982, it is well known the sensitivity of several H. pylori strains to a number of antibiotics when these are assayed in vitro. However, eradication therapies with a single antibacterial agent have failed. Recently, triple, quadruple, sequential, concomitant and hybrid therapies which include antibiotics and a proton pump inhibitor show improved eradication rate and low side effects. However, new problems have emerged. Antimicrobial resistance to the common antibiotics used has become a problem in both developed and developing countries. In particular, H. pylori clarithromycin- and metronidazole-resistant strains are a major problem in countries where H. pylori is highly prevalent. Thus, the widespread use of antibiotics is not economically feasible and might increase difficulties in the treatment of H. pylori. At present, there are no vaccines available in the market. As an alternative, effective non-antibiotic compounds should be highly desirable since their use may be safer and suitable to eradicate H. pylori. The first step in this direction has been to study the effect of medicinal herbs and natural products, such as green tea, ginseng, garlic, propolis, and probiotics, then identify their active components such as polyphenols, antioxidants, purify them, and finally test them using in vitro and in vivo H. pylori growth assays. Some of them have been quite effective. The topics related to alternative therapies for H. pylori infections and current status of their use will be discussed in the present review.

关键词： H. pylori Growth Inhibition Natural Products Herb Infusions Phytochemicals

Analysis of the postoperative hemostatic profile of colorectal cancer patients subjected to liver metastasis resection surgery

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World Journal of Clinical Cases 2019年第17期7卷 2477-2486页

作者： guillermo perez Navarro Ana Maria Pascual Bellosta Sonia María Ortega Lucea Mario Serradilla Martín Jose Manuel Ramirez Rodriguez Javier Martinez Ubieto Department of Anesthesiology University Hospital Miguel ServetZaragoza 50009Spain Department of General Surgery University Hospital Miguel ServetZaragoza 50009Spain Department of General Surgery University Hospital Lozano BlesaZaragoza 50009Spain

BACKGROUND Liver resection surgery has advanced greatly in recent years,and the adoption of fasttrack programs has yielded good *** anesthesia (general anesthesia associated to epidural analgesia) is an anesthetic-analgesic strategy commonly used for the perioperative management of patients undergoing surgery of this kind,though there is controversy regarding the coagulation alterations it may cause and which can favor the development of spinal *** To study the postoperative course of liver resection surgery,an analysis was made of the outcomes of liver resection surgery due to colorectal cancer metastases in our centre in terms of morbiditymortality and hospital stay according to the anesthetic technique used (general vs combination anesthesia).METHODS A prospective study was made of 61 colorectal cancer patients undergoing surgery due to liver metastases under general and combination anesthesia between January 2014 and October *** patient characteristics,intraoperative variables,postoperative complications,evolution of hemostatic parameters,and stay in intensive care and in hospital were *** A total of 61 patients were included in two homogeneous groups: general anesthesia (n = 30) and combination anesthesia (general anesthesia associated to epidural analgesia)(n = 31).All patients had normal coagulation values before *** international normalized ratio (INR) in both the general and combination anesthesia groups reached maximum values at 2448 h (mean 1.37 and 1.45 vs 1.39 and 1.41,respectively),followed by a gradual *** was less intraoperative bleeding in the combination anesthesia group (769 mL) than in the general anesthesia group (1200 mL)(P < 0.05).Of the 61 patients,38.8% in the general anesthesia group experienced some respiratory complication vs 6.6% in the combination anesthesia group (P < 0.001).The time to gastrointestinal tolerance was significantly correlated to the type of anesthesia,though

关键词： Hepatectomy Epidural analgesia Perioperative complications Epidural hematoma Multimodal rehabilitation Outcomes

Design and Implementation of a Rehabilitation Upper-limb Exoskeleton Robot Controlled by Cognitive and Physical Interfaces

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Journal of Bionic Engineering 2022年第5期19卷 1374-1391页

作者： Arturo Gonzalez‑Mendoza Ivett Quinones‑Uriostegui Sergio Salazar‑Cruz Alberto‑Isaac perez‑Sanpablo Ricardo Lopez‑Gutierrez Rogelio Lozano LAFMIA UMI Center for Research and AdvancedStudies of National Polytechnic InstituteAv.Instituto Politecnico Nacional No.250807360 Mexico CityMexico Motion Analysis Lab National Institute of Rehabilitation Luis Guillermo Ibarra IbarraCalz.Mexico Xochimilco No.28914389 Mexico CityMexico CONACYT-CINVESTAV Av.Instituto Politecnico Nacional 250807360 Mexico CityMexico UTC-CNRS UMR Sorbonne UniversitesUTC-CNRS UMR7253 HeudiasycCompiegneFrance

This paper presents an upper limb exoskeleton that allows cognitive(through electromyography signals)and physical user interaction(through load cells sensors)for passive and active exercises that can activate neuroplasticity in the rehabilitation process of people who suffer from a neurological *** the exoskeleton to be easily accepted by patients who suffer from a neurological injury,we used the ISO9241-210:2010 as a methodology design *** the first steps of the design process,design requirements were collected from previous usability tests and ***,as a second step,a technological solution is proposed,and as a third step,the system was evaluated through performance and user *** part of the technological solution and to allow patient participation during the rehabilitation process,we have proposed a hybrid admittance control whose input is load cell or electromyography *** hybrid admittance control is intended for active therapy exercises,is easily implemented,and does not need musculoskeletal modeling to ***,electromyography signals classification models and features were evaluated to identify the best settings for the cognitive human–robot interaction.

关键词： Human Robot interaction Hybrid admittance control Surface electromyography Upper-limb exoskeletal robot

Identifcation of Immunity-related Genes in Arabidopsis and Cassava Using Genomic Data

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Genomics, Proteomics & Bioinformatics 2013年第6期11卷 345-353页

作者： Luis guillermo Leal A'lvaro perez Andre's Quintero A'ngela Bayona Juan Felipe Ortiz Anju Gangadharan David Mackey Camilo Lo'pez Liliana Lo'pez-Kleine Department of Statistics Universidad Nacional de Colombia Department of Biology Universidad Nacional de Colombia Department of Molecular Genetics The Ohio State University

Recent advances in genomic and post-genomic technologies have provided the opportu- nity to generate a previously unimaginable amount of information. However, biological knowledge is still needed to improve the understanding of complex mechanisms such as plant immune responses. Better knowledge of this process could improve crop production and management. Here, we used holistic analysis to combine our own microarray and RNA-seq data with public genomic data from Arabidopsis and cassava in order to acquire biological knowledge about the relationships between proteins encoded by immunity-related genes （IRGs） and other genes. This approach was based on a kernel method adapted for the construction of gene networks. The obtained results allowed us to propose a list of new IRGs. A putative function in the immunity pathway was predicted for the new IRGs. The analysis of networks revealed that our predicted IRGs are either well documented or recognized in previous co-expression studies. In addition to robust relationships between IRGs, there is evidence suggesting that other cellular processes may be also strongly related to immunity.

关键词： Arabidopsis Cassava Functional gene prediction Genomic data Kernel canonical correlation ajalysi Plant immunity