期刊文献+
共找到153篇文章
< 1 2 8 >
每页显示 20 50 100
Narrow-band imaging optical chromocolonoscopy: Advantages and limitations 被引量:25
1
作者 Fabian Emura Yutaka Saito Hiroaki Ikematsu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第31期4867-4872,共6页
Narrow-band imaging (NBI) is an innovative optical technology that modifies the center wavelength and bandwidth of an endoscope's light into narrow-band illumination of 415 :1: 30 nm. NBI markedly improves capill... Narrow-band imaging (NBI) is an innovative optical technology that modifies the center wavelength and bandwidth of an endoscope's light into narrow-band illumination of 415 :1: 30 nm. NBI markedly improves capillary pattern contrast and is an in vivo method for visualizing microvessel morphological changes in superficial neoplastic lesions. The scientific basis for NBI is that short wavelength light falls within the hemoglobin absorption band, thereby facilitating clearer visualization of vascular structures. Several studies have reported advantages and limitations of NBI colonoscopy in the colorectum. One difficulty in evaluating results, however, has been nonstandardization of NBI systems (Sequential and nonsequential). Utilization of NBI technology has been increasing worldwide, but accurate pit pattern analysis and sufficient skill in magnifying colonoscopy are basic fundamentals required for proficiency in NBI diagnosis of colorectal lesions. Modern optical technology without proper image interpretation wastes resources, confuses untrained endoscopists and delays interinstitutional validation studies. Training in the principles of "optical image-enhanced endoscopy" is needed to close the gap between technological advancements and their clinical usefulness. Currently available evidence indicates that NBI constitutes an effective and reliable alternative to chromocolonoscopy for in vivo visualization of vascular structures, but further study assessing reproducibility and effectiveness in the colorectum is ongoing at various medical centers. 展开更多
关键词 Narrow-band imaging COLONOSCOPY Sequential system Non-sequential system POLYPS CHROMOENDOSCOPY
下载PDF
Fungal diversity notes 111-252-taxonomic and phylogenetic contributions to fungal taxa 被引量:10
2
作者 Hiran A.Ariyawansa Kevin D.Hyde +98 位作者 Subashini C.Jayasiri Bart Buyck K.W.Thilini Chethana Dong Qin Dai Yu Cheng Dai Dinushani A.Daranagama Ruvishika S.Jayawardena Robert Lücking Masoomeh Ghobad-Nejhad Tuula Niskanen Kasun M.Thambugala Kerstin Voigt Rui Lin Zhao Guo-Jie Li Mingkwan Doilom Saranyaphat Boonmee Zhu L.Yang Qing Cai Yang-Yang Cui Ali H.Bahkali Jie Chen Bao Kai Cui Jia Jia Chen Monika C.Dayarathne Asha J.Dissanayake Anusha H.Ekanayaka Akira Hashimoto Sinang Hongsanan E.B.Gareth Jones Ellen Larsson Wen Jing Li Qi-Rui Li Jian Kui Liu Zong Long Luo Sajeewa S.N.Maharachchikumbura Ausana Mapook Eric H.C.McKenzie Chada Norphanphoun Sirinapa Konta Ka Lai Pang Rekhani H.Perera Rungtiwa Phookamsak Chayanard Phukhamsakda Umpava Pinruan Emile Randrianjohany Chonticha Singtripop Kazuaki Tanaka Cheng Ming Tian Saowaluck Tibpromma Mohamed A.Abdel-Wahab Dhanushka N.Wanasinghe Nalin N.Wijayawardene Jin-Feng Zhang Huang Zhang Faten A.Abdel-Aziz Mats Wedin Martin Westberg Joseph F.Ammirati Timur S.Bulgakov Diogo X.Lima Tony M.Callaghan Philipp Callac Cheng-Hao Chang Luis F.Coca Manuela Dal-Forno Veronika Dollhofer Kateřina Fliegerová Katrin Greiner Gareth W.Griffith Hsiao-Man Ho Valerie Hofstetter Rajesh Jeewon Ji Chuan Kang Ting-Chi Wen Paul M.Kirk Ilkka Kytövuori James D.Lawrey Jia Xing Hong Li Zou Yi Liu Xing Zhong Liu Kare Liimatainen H.Thorsten Lumbsch Misato Matsumura Bibiana Moncada Salilaporn Nuankaew Sittiporn Parnmen AndréL.C.M.de Azevedo Santiago Sujinda Sommai Yu Song Carlos A.F.de Souza Cristina M.de Souza-Motta Hong Yan Su Satinee Suetrong Yong Wang Syuan-Fong Wei Ting Chi Wen Hai Sheng Yuan Li Wei Z 《Fungal Diversity》 SCIE 2015年第6期27-274,共248页
This paper is a compilation of notes on 142 fungal taxa,including five new families,20 new genera,and 100 new species,representing a wide taxonomic and geographic range.The new families,Ascocylindricaceae,Caryosporace... This paper is a compilation of notes on 142 fungal taxa,including five new families,20 new genera,and 100 new species,representing a wide taxonomic and geographic range.The new families,Ascocylindricaceae,Caryosporaceae and Wicklowiaceae(Ascomycota)are introduced based on their distinct lineages and unique morphology.The new Dothideomycete genera Pseudomassariosphaeria(Amniculicolaceae),Heracleicola,Neodidymella and Pseudomicrosphaeriopsis(Didymellaceae),Pseudopithomyces(Didymosphaeriaceae),Brunneoclavispora,Neolophiostoma and Sulcosporium(Halotthiaceae),Lophiohelichrysum(Lophiostomataceae),Galliicola,Populocrescentia and Vagicola(Phaeosphaeriaceae),Ascocylindrica(Ascocylindricaceae),Elongatopedicellata(Roussoellaceae),Pseudoasteromassaria(Latoruaceae)and Pseudomonodictys(Macrodiplodiopsidaceae)are introduced.The newly described species of Dothideomycetes(Ascomycota)are Pseudomassariosphaeria bromicola(Amniculicolaceae),Flammeascoma lignicola(Anteagloniaceae),Ascocylindrica marina(Ascocylindricaceae),Lembosia xyliae(Asterinaceae),Diplodia crataegicola and Diplodia galiicola(Botryosphaeriaceae),Caryospora aquatica(Caryosporaceae),Heracleicola premilcurensis and Neodidymella thailandicum(Didymellaceae),Pseudopithomyces palmicola(Didymosphaeriaceae),Floricola viticola(Floricolaceae),Brunneoclavispora bambusae,Neolophiostoma pigmentatum and Sulcosporium thailandica(Halotthiaceae),Pseudoasteromassaria fagi(Latoruaceae),Keissleriella dactylidicola(Lentitheciaceae),Lophiohelichrysum helichrysi(Lophiostomataceae),Aquasubmersa japonica(Lophiotremataceae),Pseudomonodictys tectonae(Macrodiplodiopsidaceae),Microthyrium buxicola and Tumidispora shoreae(Microthyriaceae),Alloleptosphaeria clematidis,Allophaeosphaeria cytisi,Allophaeosphaeria subcylindrospora,Dematiopleospora luzulae,Entodesmium artemisiae,Galiicola pseudophaeosphaeria,Loratospora luzulae,Nodulosphaeria senecionis,Ophiosphaerella aquaticus,Populocrescentia forlicesenensis and Vagicola vagans(Phaeosphaeriaceae),Elongatopedicellata lignicola,Roussoella magnatum an 展开更多
关键词 Fungi Taxonomy New genus New species PHYLOGENY
原文传递
Gastric mucosa-associated lymphoid tissue lymphomas and Helicobacter pylori infection:A Colombian perspective 被引量:7
3
作者 Sally Yepes Maria Mercedes Torres +1 位作者 Carlos Saavedra Rafael Andrade 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第7期685-691,共7页
AIM: To assess the significance of chromosome translo- cation t(11;18)(q21;q21), B-cell lymphoma 10 (BCL-10) protein and He/icobacter py/ori (H. py/on) infection in gastric mucosa-associated lymphoid tissue ... AIM: To assess the significance of chromosome translo- cation t(11;18)(q21;q21), B-cell lymphoma 10 (BCL-10) protein and He/icobacter py/ori (H. py/on) infection in gastric mucosa-associated lymphoid tissue (MALT) lymphoma in Colombia. 展开更多
关键词 Mucosa-associated lymphoid tissue lympho-ma Helicobacter pylori TREATMENT t(11 18)(q21 q21 B-cell lymphoma 10
下载PDF
Effect of music therapy on short-term psychological and physiological outcomes in mechanically ventilated patients:A randomized clinical pilot study
4
作者 Mark Ettenberger Rosangela Casanova-Libreros +7 位作者 Josefina Chávez-Chávez Jose Gabriel Cordoba-Silva William Betancourt-Zapata Rafael Maya Lizeth Alexa Fandino-Vergara Mario Valderrama Ingrid Silva-Fajardo Sandra Milena Hernández-Zambrano 《Journal of Intensive Medicine》 CSCD 2024年第4期515-525,共11页
Background:Elevated anxiety levels are common in patients on mechanical ventilation(MV)and may challenge recovery.Research suggests music-based interventions may reduce anxiety during MV.However,studies inves-tigating... Background:Elevated anxiety levels are common in patients on mechanical ventilation(MV)and may challenge recovery.Research suggests music-based interventions may reduce anxiety during MV.However,studies inves-tigating specific music therapy techniques,addressing psychological and physiological well-being in patients on MV,are scarce.Methods:This three-arm randomized clinical pilot study was conducted with MV patients admitted to the intensive care unit(ICU)of Hospital San Joséin Bogotá,Colombia between March 7,2022,and July 11,2022.Patients were divided into three groups:intervention group 1(IG1),music-assisted relaxation;intervention group 2(IG2),patient-preferred therapeutic music listening;and control group(CG),standard care.The main outcome measure was the 6-item State-Anxiety Inventory.Secondary outcomes were:pain(measured with a visual analog scale),resilience(measured with the Brief Resilience Scale),agitation/sedation(measured with the Richmond Agitation-Sedation Scale),vital signs(including heart rate,blood pressure,oxygen saturation,and respiratory rate),days of MV,extubation success,and days in the ICU.Additionally,three patients underwent electroencephalography during the interventions.Results:Data from 23 patients were analyzed in this study.The age range of the patients was 24.0-84.0 years,with a median age of 66.0 years(interquartile range:57.0-74.0).Of the 23 patients,19 were female(82.6%).No statistically significant differences between the groups were observed for anxiety(P=0.330),pain(P=0.624),resilience(P=0.916),agitation/sedation(P=0.273),length of ICU stay(P=0.785),or vital signs.A statistically significant difference between the groups was found for days of MV(P=0.019).Electroencephalography mea-surements showed a trend toward delta and theta band power decrease for two patients and a power increase on both beta frequencies(slow and fast)in the frontal areas of the brain for one patient.Conclusions:In this pilot study,music therapy did not significantly affect the anxiety levels in patien 展开更多
关键词 Music therapy Mechanical ventilation Intensive care unit ANXIETY PAIN
原文传递
Neuropsychological Profile of a Patient with Acquired Brain Damage Following Vascular Lesion of the Left Anterior Cingulate Cortex
5
作者 Jimmy Zúñiga-Márquez Lina Borda-Camargo +4 位作者 Diego Buitrago-Mora Lorely Guerra-Valdés Laura González Patricia Quintero-Cusgüen Nataly Gutierrez-Ávila 《Neuroscience & Medicine》 2024年第1期66-75,共10页
Stroke is a physiological alteration associated with changes in blood flow that can result in sudden-onset cognitive impairment. It has a heterogenous clinical presentation with varying degrees of severity correlated ... Stroke is a physiological alteration associated with changes in blood flow that can result in sudden-onset cognitive impairment. It has a heterogenous clinical presentation with varying degrees of severity correlated with specific central nervous system zones or areas, and its prognosis is uncertain. This case study describes a 62-year-old male patient with acquired brain damage of the anterior cingulate cortex as a result of an ischemic event in the territory of the left anterior cerebral artery. Cognitive function was assessed using the neuropsychological executive function and frontal lobe test battery (BANFE-2) as well as other neuropsychological tests. The results show a profile of higher mental functions characterized by the presence of dysexecutive syndrome with marked behavioral alteration and diencephalic amnesia. . 展开更多
关键词 Ischemic Stroke Anterior Cingulate Cortex NEUROPSYCHOLOGY Acquired Brain Damage
下载PDF
Efficiency and sustainability of the tourism industry in Latin America
6
作者 Clara Inés PARDO MARTÍNEZ Alexander COTTE POVEDA 《Regional Sustainability》 2024年第4期57-70,共14页
The tourism industry is economically very important.According to the World Travel Tourism Council,in 2019,the tourism industry accounted for a quarter of all new jobs created worldwide,10.3%of all jobs,and 9.6×10... The tourism industry is economically very important.According to the World Travel Tourism Council,in 2019,the tourism industry accounted for a quarter of all new jobs created worldwide,10.3%of all jobs,and 9.6×1012 USD of the global gross domestic product.This study aimed to calculate the tourism efficiency index for different Latin American countries from 2010 to 2021 using data envelopment analysis,which analyzes the relationships between input variables(including the number of employees in the tourism industry and the number of hotel-type establishments)and output variables(including tourism expenditures in other countries and public social expenditures in recreation and culture per capita).Additionally,this study aimed to identify the countries with greater tourism development and the factors that may affect the development of the tourism industry through the stochastic frontier production function.The results of the tourism efficiency index for Central America(including Costa Rica,Dominica,El Salvador,Honduras,Mexico,and Panama)and South America(including Argentina,Brazil,Chile,Colombia,Ecuador,Paraguay,Peru,and Uruguay)exhibited different trends.However,after the global health crisis,the tourism industry recovered,showing new opportunities to promote sustainability.The results of the stochastic frontier production function demonstrated that countries with higher levels of inbound and outbound tourism,contribution of tourism to the economy,natural resources,and literacy rate exhibited more efficient tourism industry,whereas countries with higher pollution levels exhibited less efficient tourism industry.The findings of this study could allow us to formulate suitable public policies to promote tourism,maintain natural resources,and diversify these sectors with more inclusive programmes that can facilitate growth and benefit vulnerable communities. 展开更多
关键词 Tourism industry Tourism efficiency index Stochastic frontier production function Data envelopment analysis(DEA) Latin America
下载PDF
Mesial temporal sclerosis and epilepsy:a narrative review
7
作者 Daniel Villamizar-Torres Andrea Carolina Cepeda Trillos Alejandro Vargas-Moreno 《Acta Epileptologica》 2024年第3期178-188,共11页
Mesial temporal sclerosis(MTS)stands out as a prevalent etiology of medically intractable temporal lobe epilepsy.Understanding the pathological alterations,clinical manifestations and risk factors of MTS is crucial fo... Mesial temporal sclerosis(MTS)stands out as a prevalent etiology of medically intractable temporal lobe epilepsy.Understanding the pathological alterations,clinical manifestations and risk factors of MTS is crucial for the recognition and suspicion of this condition.In this paper,we provide a comprehensive narrative review on the pathophysiology,clinical manifestations,and treatment options for MTS.By doing so,we aim to provide an up-to-date understanding of this condition. 展开更多
关键词 Hippocampal sclerosis EPILEPSY Temporal lobe HIPPOCAMPUS
原文传递
Science,technology,and innovation in health for the next twenty years:A survey analysis in Colombia
8
作者 Oscar Espinosa Gabriela Puentes +2 位作者 Jhonathan Rodríguez Adriana Robayo Juan-Manual Anaya 《Health Care Science》 2024年第2期78-87,共10页
Background:Colombia is a Latin American country with a very complex social and political context that has not allowed the allocation of sufficient resources to the fields of science,technology,and innovation(STI).This... Background:Colombia is a Latin American country with a very complex social and political context that has not allowed the allocation of sufficient resources to the fields of science,technology,and innovation(STI).This is particularly worrying for the area of health since not enough resources are allocated for public health,research,or education.Methods:The so-called“Great Survey in Health 2019”was administered online through the SurveyMonkey platform to 5298 people in different regions of the country,representing the public,private,and academic sectors.The questionnaire consisted of 46 open and closed questions,including demographic inquiries.Data analysis involved textual analytics and sentiment analysis.Results:Overall,56%of those surveyed were women within the adult life cycle.Most respondents had a postgraduate education.Greater participation was observed in the Oriental,Bogotá,and Antioquia regions,which also concentrate the largest number of resources for STI.Among the main recommendations derived from the results,priorities include investing in research,personalised medicine,promoting the social appropriation of knowledge,addressing mental health,regulating research through a statute,promoting undergraduate research,and establishing recertification exams to pursue excellence.Conclusion:The results of this original study serve as a fundamental input to promote and strengthen the STI processes in life sciences and health.They serve as a guide to generate public policies and actions that guarantee better health and well-being for the Colombian population,strategically proposing a clear roadmap for the next 20 years. 展开更多
关键词 HEALTH SURVEY SCIENCE TECHNOLOGY innovation Colombia public health text analytics
下载PDF
A systematic review of real-time detection and classification of power quality disturbances 被引量:3
9
作者 Joaquín E.Caicedo Daniel Agudelo-Martínez +1 位作者 Edwin Rivas-Trujillo Jan Meyer 《Protection and Control of Modern Power Systems》 SCIE EI 2023年第1期30-66,共37页
This paper offers a systematic literature review of real-time detection and classification of Power Quality Disturbances(PQDs).A particular focus is given to voltage sags and notches,as voltage sags cause huge economi... This paper offers a systematic literature review of real-time detection and classification of Power Quality Disturbances(PQDs).A particular focus is given to voltage sags and notches,as voltage sags cause huge economic losses while research on voltage notches is still very incipient.A systematic method based on scientometrics,text similarity and the analytic hierarchy process is proposed to structure the review and select the most relevant literature.A biblio-metric analysis is then performed on the bibliographic data of the literature to identify relevant statistics such as the evolution of publications over time,top publishing countries,and the distribution by relevant topics.A set of articles is subsequently selected to be critically analyzed.The critical review is structured in steps for real-time detection and classification of PQDs,namely,input data preparation,preprocessing,transformation,feature extraction,feature selec-tion,detection,classification,and characterization.Aspects associated with the type of disturbance(s)addressed in the literature are also explored throughout the review,including the perspectives of those studies aimed at multiple PQDs,or specifically focused on voltage sags or voltage notches.The real-time performance of the reviewed tools is also examined.Finally,unsolved issues are discussed,and prospects are highlighted. 展开更多
关键词 Bibliometric analysis CLASSIFICATION Detection Power quality(PQ) REAL-TIME Systematic review Voltage sag Voltage notch
原文传递
Alkali and Plasma-Treated Guadua angustifolia Bamboo Fibers:A Study on Reinforcement Potential for Polymeric Matrices
10
作者 Patricia Luna Juan Lizarazo-Marriaga Alvaro Mariño 《Journal of Renewable Materials》 EI CAS 2024年第8期1399-1416,共18页
This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite materials.Chemical(alkali)and physical(dry etching plasma)treatments were used s... This study focuses on treating Guadua angustifolia bamboo fibers to enhance their properties for reinforcement applications in composite materials.Chemical(alkali)and physical(dry etching plasma)treatments were used separately to augment compatibility of Guadua angustifolia fibers with various composite matrices.The influence of these treatments on the fibers’performance,chemical composition,and surface morphology were analyzed.Statistical analysis indicated that alkali treatments reduced the tensile modulus of elasticity and strength of fibers by up to 40%and 20%,respectively,whereas plasma treatments maintain the fibers’mechanical performance.FTIR spectroscopy revealed significant alterations in chemical composition due to alkali treatments,while plasma-treated fibers showed minimal changes.Surface examination through Scanning Electron Microscopy(SEM)revealed post-treatment modifications in both cases;alkali treatments served as a cleanser,eliminating lignin and hemicellulose from the fiber surface,whereas plasma treatments also produce rough surfaces.These results validate the impact of the treatments on the fiber mechanical performance,which opens up possibilities for using Guadua angustifolia fibers as an alternative reinforcement in composite manufacturing. 展开更多
关键词 Bamboo fibers Guadua angustifolia alkali treatment dry etching plasma treatment composite reinforcement
下载PDF
Mechanical Behavior of Panels Reinforced with Orthogonal Plant Fabrics: Experimental and Numerical Assessment
11
作者 Martha L.Sánchez G.Capote 《Journal of Renewable Materials》 EI CAS 2024年第10期1791-1810,共20页
The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional materials.The production of cement,steel,a... The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional materials.The production of cement,steel,and other conventional materials impacts both ecosystems and human health,increasing the demand for ecological and biodegradable alternatives.In this paper,we analyze the properties of panels made from a combination of plant fibers and castor oil resin,analyzing the viability of their use as construction material.For the research,orthogonal fabrics made with waste plant fibers supplied by a company that deals with the manufacture of furniture and craft products were used.These fabrics were made with strips of plant fibers of the Calamus rotang,Bambusa vulgaris,Heteropsis flexuosa,and Salix viminalis species.To improve their compatibility with the castor oil resin,a cold argon plasma treatment was applied.The effect of the treatment on the properties of the fibers and the panels was analyzed.The density,water absorption capacity,and swelling percentage were evaluated.Tensile,compression,static bending,and linear buckling tests were carried out.The study found that panels made with treated fiber fabrics exhibited a reduction of approximately 10%in absorption capacity and up to 35%in swelling percentage values.Panels made with Bambusa vulgaris fabrics exhibited the highest strength and stiffness values.Numerical models were constructed using commercial finite element software.When comparing the numerical results with the experimental ones,differences of less than 15%were seen,demonstrating that the models allow adequately predicting the analyzed properties.On comparing the values obtained with the characteristic values of oriented strand board,the results suggest that panels made with unconventional materials could replace commercial panels traditionally made with wood-based fibers and particles and other composite materials in several applications in the construction industry. 展开更多
关键词 Unconventional materials nonstructural panels plantfibers surface treatment physical properties mechanical properties
下载PDF
Depth to the bottom of magnetic layer in South America and its relationship to Curie isotherm,Moho depth and seismicity behavior 被引量:6
12
作者 Javier Idárraga-García Carlos A.Vargas 《Geodesy and Geodynamics》 2018年第1期93-107,共15页
We have estimated the DBML(depth to the bottom of the magnetic layer) in South America from the inversion of magnetic anomaly data extracted from the EMAG2 grid. The results show that the DBML values, interpreted as... We have estimated the DBML(depth to the bottom of the magnetic layer) in South America from the inversion of magnetic anomaly data extracted from the EMAG2 grid. The results show that the DBML values, interpreted as the Curie isotherm, vary between -10 and -60 km. The deepest values(〉-45) are mainly observed forming two anomalous zones in the central part of the Andes Cordillera. To the east of the Andes, in most of the stable cratonic area of South America, intermediate values(between -25 and-45 km) are predominant. The shallowest values(〈-25 km) are present in northwestern corner of South America, southern Patagonia, and in a few sectors to the east of the Andes Cordillera. Based on these results, we estimated the heat flow variations along the study area and found a very good correlation with the DBML. Also striking is the observation that the thermal anomalies of low heat flow are closely related to segments of flat subduction, where the presence of a cold and thick subducting oceanic slab beneath the continent, with a virtual absence of hot mantle wedge, leads to a decrease in the heat transfer from the deeper parts of the system.After comparing our results with the Moho depths reported by other authors, we have found that the Curie isotherm is deeper than Moho in most of the South American Platform(northward to -20°S), which is located in the stable cratonic area at the east of the Andes. This is evidence that the lithospheric mantle here is magnetic and contributes to the long wavelength magnetic signal. Also, our results support the hypothesis that the Curie isotherm may be acting as a boundary above which most of the crustal seismicity is concentrated. Below this boundary the occurrence of seismic events decreases dramatically. 展开更多
关键词 Magnetic layer depth Curie isotherm Heat flow Crustal seismicity Flat subduction South America
下载PDF
Behavior of diatomaceous soil in lacustrine deposits of Bogota, Colombia 被引量:6
13
作者 Bernardo Caicedo Cristhian Mendoza +1 位作者 Fernando López Arcesio Lizcano 《Journal of Rock Mechanics and Geotechnical Engineering》 CSCD 2018年第2期367-379,共13页
This work presents a study on the behaviors of diatomaceous soils. Although studies are rarely reported on these soils, they have been identified in Mexico City, the Sea of Japan, the northeast coast of Australia,the ... This work presents a study on the behaviors of diatomaceous soils. Although studies are rarely reported on these soils, they have been identified in Mexico City, the Sea of Japan, the northeast coast of Australia,the equatorial Pacific, and the lacustrine deposit of Bogota(Colombia), among other locations. Features of this kind of soil include high friction angle, high initial void ratio, high compressibility index, high liquid limit, and low density. Some of these features are counterintuitive from a classical soil mechanics viewpoint. To understand the geotechnical properties of the diatomaceous soil, a comprehensive experimental plan consisting of more than 2400 tests was performed, including physical tests such as grain size distribution, Atterberg limits, density of solid particles, and organic matter content; and mechanical tests such as oedometric compression tests, unconfined compression tests, and triaxial tests.Laboratory tests were complemented with scanning electron microscope(SEM) observations to evaluate the microstructure of the soil. The test results show that there is an increase in liquid limit with increasing diatomaceous content, and the friction angle also increases with increasing diatomaceous content. In addition, several practical correlations were proposed for this soil type for shear strength mobilization and intrinsic compression line. Finally, useful correlations were presented, such as the relationship between the state consistency and the undrained shear strength, the friction angle and the liquid limit, the void ratio at 100 kPa and the liquid limit, the plasticity index and the diatomaceous content, among others. 展开更多
关键词 Diatomaceous soil Soft soils COMPRESSIBILITY Friction angle Natural soil
下载PDF
Metabolic Syndrome and Perioperative Complications during Scheduled Surgeries with Spinal Anesthesia 被引量:6
14
作者 José Pomares Gustavo Mora-García +3 位作者 Roberto Palomino Yéssika De León Claudio Gómez-Alegría Doris Gómez-Camargo 《Open Journal of Anesthesiology》 2014年第7期167-176,共10页
Background: Metabolic syndrome (MS) is a constellation of factors associated with increased risk of developing cardiovascular diseases and Diabetes Mellitus. Despite of the many studies related to MS, little is known ... Background: Metabolic syndrome (MS) is a constellation of factors associated with increased risk of developing cardiovascular diseases and Diabetes Mellitus. Despite of the many studies related to MS, little is known about its impact on scenarios such as surgical anesthesia. Objective: To examine the correlation between demographic and metabolic variables with the occurrence of perioperative complications in patients with MS undergoing scheduled surgeries using a spinal anesthesia technique in the surgery department at the University Clinic San Juan de Dios in Cartagena de Indias, Colombia. Methods: Observational, analytical, cross-sectional, single-center study of 150 subjects with MS and 150 control subjects. Perioperative complications, socio-demographic, hemodynamic and respiratory variables were registered. Groups were compared using t test, Fisher’s exact test or Chi-square, as appropriate. We applied a logistic multiple regression model, adjusted by backward stepwise at 0.25 and forward at 0.05, to find possible incompatible associations. p value < 0.05 was considered significant. Results: There were significant differences between groups in age, American Society of Anesthesiologists physical status classification, frequency of diseases associated to MS and perioperative complications. There were no cases of mortality among patients. There was statistically significant difference between the two groups for intraoperative hypotension and hypertension with p values of <0.0001 and 0.034. Among postoperative complications there was statistically significant difference in pain (13.3% vs 5.3% in patients without MS) and nausea and/or postoperative vomiting (8% vs 2% in patients without MS) with a p value of 0.027 and 0.015 (by Fisher) respectively. Conclusions: Metabolic abnormalities in MS are a risk factor for developing complications in the perioperative period of patients scheduled for surgeries using the subarachnoid anesthesia technique. Accordingly, it is appropriate to implement health intervention str 展开更多
关键词 Metabolic Syndrome X INSULIN Resistance SPINAL ANESTHESIA ABDOMINAL Obesity PERIOPERATIVE Period
下载PDF
Robust Disturbance Rejection Based Control with Extended-state Resonant Observer for Sway Reduction in Uncertain Tower-cranes 被引量:2
15
作者 Horacio Coral-Enriquez Santiago Pulido-Guerrero John Cortés-Romero 《International Journal of Automation and computing》 EI CSCD 2019年第6期812-827,共16页
In this paper, the problem of load transportation and robust mitigation of payload oscillations in uncertain tower-cranes is addressed. This problem is tackled through a control scheme based on the philosophy of activ... In this paper, the problem of load transportation and robust mitigation of payload oscillations in uncertain tower-cranes is addressed. This problem is tackled through a control scheme based on the philosophy of active-disturbance-rejection. Here, a general disturbance model built with two dominant components: polynomial and harmonic, is stated. Then, a disturbance observer is formulated through state-vector augmentation of the tower-crane model. Thus, better performance of estimations for system states and disturbances is achieved. The control law is then formulated to actively reject the disturbances but also to accommodate the closed-loop system dynamics even under system uncertainty. The proposed control schema is validated via experimentation using a small-scale tower-crane,and compared with other relevant active disturbance rejection control(ADRC)-based techniques. The experimental results show that the proposed control scheme is robust under parametric uncertainty of the system, and provides improved attenuation of payload oscillations even under system uncertainty. 展开更多
关键词 Active DISTURBANCE rejection control(ADRC) EXTENDED state observer(ESO) tower-crane CONTROL RESONANT OBSERVER DISTURBANCE OBSERVER linear matrix inequality
原文传递
An Algorithm for Optimal Firewall Placement in IEC61850 Substations 被引量:3
16
作者 Hermes Eslava Luis Alejandro Rojas Danny Pineda 《Journal of Power and Energy Engineering》 2015年第4期16-22,共7页
Recently, most electric power substations have adopted production control systems, such as SCADA systems, which communicate with field devices and remotely control processes from a computer screen. However, these syst... Recently, most electric power substations have adopted production control systems, such as SCADA systems, which communicate with field devices and remotely control processes from a computer screen. However, these systems together with protection measures and additional control actions (using protocol IEC61850) seem not to be enough to free substations of security attacks (e.g. virus, intruders, forgery or unauthorized data manipulation). This paper analyzes the main features of an electric power substation together with the aspects that might be significantly affected by cyber-attacks. The paper also presents the implementation of a specific security system (i.e. firewall-wise system) intended to protect a target distribution network. 展开更多
关键词 FIREWALL SECURITY SUBSTATIONS ELECTRIC Power IEC61850
下载PDF
Academic Stress Assessment Using Virtual Reality as an Educational Tool in Spine Surgery
17
作者 Diana Chávez Lizárraga Jesús Alberto Pérez Contreras +4 位作者 Fernando Alvarado Gómez Evelyn Quintero Medina Emmanuel Cantú Chávez Iván Ulises Sámano López Ana Sofía Peña Blesa 《Open Journal of Modern Neurosurgery》 2024年第2期114-123,共10页
Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching... Introduction: The evaluation of academic stress in medical students and residents is a topic of significant interest, given the considerable challenges they face during their learning process with traditional teaching methods. The use of technologies like virtual reality presents an opportunity to enhance their skills through simulations and training. The main objective of this study is to qualitatively assess the stress levels experienced by medical students and residents by integrating virtual reality into their current learning methods, aiming to improve their ability to manage stressors in their practice. Material and Methods: A questionnaire was conducted with 12 medical students and 12 Traumatology and orthopedics residents. The purpose of the questionnaire was to evaluate the levels of academic stress using the SISCO inventory. The stress levels were calculated by transforming average values into percentages, and the following criteria were assigned: 0 to 33% for Mild Stress, 34 to 66% for Moderate Stress, and 67 to 100% for Deep Stress. Then, a virtual reality class focused on spine surgery was provided. Both medical students and residents were trained using the Non Nocere SharpSurgeon software platform and Oculus Quest 2 virtual reality glasses. At the end of the session, a second questionnaire related to the practice with virtual reality was conducted with the same evaluation criteria and a comparative analysis was carried out. Results: 12 undergraduate students from Hospital Angeles Mexico, CDMX and 12 traumatology and orthopedics residents at Hospital Santa Fe, Bogota were evaluated. The students in CDMX reported an average qualitative stress of 28.50% during habitual practices, which decreased to an average of 14.67% after virtual reality practice. Residents in Bogotá experienced an average qualitative stress of 30.50% with their current learning methods but this reduced to an average of 13.92% after using virtual reality. These findings indicate that the use of virtual reality has a positive impact 展开更多
关键词 Virtual Reality Academic Stress Learning Strategies Spine Surgery Training
下载PDF
Depression Intensity Classification from Tweets Using Fast Text Based Weighted Soft Voting Ensemble
18
作者 Muhammad Rizwan Muhammad Faheem Mushtaq +5 位作者 Maryam Rafiq Arif Mehmood Isabel de la Torre Diez Monica Gracia Villar Helena Garay Imran Ashraf 《Computers, Materials & Continua》 SCIE EI 2024年第2期2047-2066,共20页
Predicting depression intensity from microblogs and social media posts has numerous benefits and applications,including predicting early psychological disorders and stress in individuals or the general public.A major ... Predicting depression intensity from microblogs and social media posts has numerous benefits and applications,including predicting early psychological disorders and stress in individuals or the general public.A major challenge in predicting depression using social media posts is that the existing studies do not focus on predicting the intensity of depression in social media texts but rather only perform the binary classification of depression and moreover noisy data makes it difficult to predict the true depression in the social media text.This study intends to begin by collecting relevant Tweets and generating a corpus of 210000 public tweets using Twitter public application programming interfaces(APIs).A strategy is devised to filter out only depression-related tweets by creating a list of relevant hashtags to reduce noise in the corpus.Furthermore,an algorithm is developed to annotate the data into three depression classes:‘Mild,’‘Moderate,’and‘Severe,’based on International Classification of Diseases-10(ICD-10)depression diagnostic criteria.Different baseline classifiers are applied to the annotated dataset to get a preliminary idea of classification performance on the corpus.Further FastText-based model is applied and fine-tuned with different preprocessing techniques and hyperparameter tuning to produce the tuned model,which significantly increases the depression classification performance to an 84%F1 score and 90%accuracy compared to baselines.Finally,a FastText-based weighted soft voting ensemble(WSVE)is proposed to boost the model’s performance by combining several other classifiers and assigning weights to individual models according to their individual performances.The proposed WSVE outperformed all baselines as well as FastText alone,with an F1 of 89%,5%higher than FastText alone,and an accuracy of 93%,3%higher than FastText alone.The proposed model better captures the contextual features of the relatively small sample class and aids in the detection of early depression intensity predict 展开更多
关键词 Depression classification deep learning FastText machine learning
下载PDF
Effect of full-fat sunflower or flaxseed seeds dietary inclusion on performance,egg yolk fatty acid profile and egg quality in laying hens 被引量:4
19
作者 Yandy J.Aguillón-Páez Laura A.Romero Gonzalo J.Diaz 《Animal Nutrition》 SCIE 2020年第2期179-184,共6页
A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed of full-fat sunflower seeds on performance parameters,egg quality parameters and egg yolk fatty acid profile in laying hens.A ... A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed of full-fat sunflower seeds on performance parameters,egg quality parameters and egg yolk fatty acid profile in laying hens.A total of 150 Babcock Brown hens at 27 weeks of age were distributed in 3 experimental treatments,as follows:T1,control;T2,diet containing 13.5% full-fat whole flaxseed seeds;and T3,diet containing 13.5% full-fat ground sunflower seeds.Feed and water were provided ad libitum and the experiment lasted for 8 weeks.No significant differences were found on egg quality parameters,but total egg production and rate of lay were significantly(P <0.05) lower in the group receiving sunflower seeds compared with the control,and significant differences(P <0.05) in egg yolk saturated,monounsaturated,polyunsaturated,omega-6(n-6) and omega-3(n-3) fatty acids were observed,as well as in the n-6:n-3 ratio.The results show that the dietary inclusion of 13.5% flaxseed full-fat seeds significantly increases the n-3 polyunsaturated fatty acid(PUFA) content in the eggs and lowers the n-6:n-3 ratio without affecting performance parameters.Inclusion of full-fat sunflower seeds increases the n-6 PUFA content but affects total egg production and rate of lay.Further studies are needed to determine the level of inclusion of full-fat sunflower seeds that does not affect performance. 展开更多
关键词 FLAXSEED SUNFLOWER Polyunsaturated fatty acid Laying hens Egg quality PERFORMANCE
原文传递
Hepatic angiosarcoma presenting as acute liver failure in young adults. Report of two cases and review of literature 被引量:1
20
作者 Rocío López Diana Castro-Villabón +2 位作者 Johanna álvarez Alonso Vera Rafael Andrade 《Case Reports in Clinical Medicine》 2013年第8期439-444,共6页
Background: Hepatic angiosarcoma is a rare tumor of endothelial origin that accounts for up to 2% of all primary neoplasms of the liver. It is uncommon in young adults and acute liver failure is a very unusual present... Background: Hepatic angiosarcoma is a rare tumor of endothelial origin that accounts for up to 2% of all primary neoplasms of the liver. It is uncommon in young adults and acute liver failure is a very unusual presentation of this disease. Case Presentation: We report the cases of two young male adults who presented with acute liver failure. One of them was diagnosed with primary hepatic angiosarcoma after transplantation based on the complete evaluation of the heaptectomy specimen;while the other was diagnosed through a liver biopsy which was done as part of the work-up for transplantation. Both patients had a rapidly worsening clinical course and died within 2 months of diagnosis. Conclusion: Hepatic angiosarcoma is a poor prognosis disease with high and early mortality. Therefore, a high level of suspicion should be present to promptly diagnose it, especially when dealing with patients with a rapidly worsening liver disease. 展开更多
关键词 LIVER HEPATIC ANGIOSARCOMA ACUTE LIVER Failure
下载PDF
上一页 1 2 8 下一页 到第
使用帮助 返回顶部