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1.
Environ Monit Assess ; 196(11): 1043, 2024 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-39390120

RESUMO

Water pollution originating from land use and land cover (LULC) can disrupt river ecosystems, posing a threat to public health, safety, and socioeconomic sustainability. Although the interactions between terrestrial and aquatic systems have been investigated for decades, the scale at which land use practices, whether in the entire basin or separately in parts, significantly impact water quality still needs to be determined. In this research, we used multitemporal data (field measurements, Sentinel 2 images, and elevation data) to investigate how the LULC composition in the catchment area (CA) of each water pollution measurement station located in the river course of the Los Perros Basin affects water pollution indicators (WPIs). We examined whether the CAs form a sequential runoff aggregation system for certain pollutants from the highest to the lowest part of the basin. Our research applied statistical (correlation, time series analysis, and canonical correspondence analysis) and geo-visual analyses to identify relationships at the CA level between satellite-based LULC composition and WPI concentrations. We observed that pollutants such as nitrogen, phosphorus, coliforms, and water temperature form a sequential runoff aggregation system from the highest to the lowest part of the basin. We concluded that the observed decrease in natural cover and increase in built-up and agricultural cover in the upper CAs of the study basin between the study period (2016 to 2020) are related to elevated WPI values for suspended solids and coliforms, which exceeded the allowed limits on all CAs and measured dates.


Assuntos
Monitoramento Ambiental , Fósforo , Rios , Poluentes Químicos da Água , México , Rios/química , Poluentes Químicos da Água/análise , Fósforo/análise , Agricultura , Nitrogênio/análise , Poluição da Água/estatística & dados numéricos
2.
Sensors (Basel) ; 22(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36366095

RESUMO

The rise of digitalization, sensory devices, cloud computing and internet of things (IoT) technologies enables the design of novel digital product lifecycle management (DPLM) applications for use cases such as manufacturing and delivery of digital products. The verification of the accomplishment/violations of agreements defined in digital contracts is a key task in digital business transactions. However, this verification represents a challenge when validating both the integrity of digital product content and the transactions performed during multiple stages of the DPLM. This paper presents a traceability method for DPLM based on the integration of online and offline verification mechanisms based on blockchain and fingerprinting, respectively. A blockchain lifecycle registration model is used for organizations to register the exchange of digital products in the cloud with partners and/or consumers throughout the DPLM stages as well as to verify the accomplishment of agreements at each DPLM stage. The fingerprinting scheme is used for offline verification of digital product integrity and to register the DPLM logs within digital products, which is useful in either dispute or violation of agreements scenarios. We built a DPLM service prototype based on this method, which was implemented as a cloud computing service. A case study based on the DPLM of audios was conducted to evaluate this prototype. The experimental evaluation revealed the ability of this method to be applied to DPLM in real scenarios in an efficient manner.


Assuntos
Blockchain , Internet das Coisas , Segurança Computacional , Computação em Nuvem , Tecnologia
3.
In. Vicente Peña, Ernesto. Medicina interna. Diagnóstico y tratamiento. 3ra ed. La Habana, Editorial Ciencias Médicas, 3 ed; 2022. .
Monografia em Espanhol | CUMED | ID: cum-79062
4.
In. Vicente Peña, Ernesto. Medicina interna. Diagnóstico y tratamiento. 3ra ed. La Habana, Editorial Ciencias Médicas, 3 ed; 2022. , tab, ilus.
Monografia em Espanhol | CUMED | ID: cum-79057
5.
In. Vicente Peña, Ernesto. Medicina interna. Diagnóstico y tratamiento. 3ra ed. La Habana, Editorial Ciencias Médicas, 3 ed; 2022. , tab, ilus.
Monografia em Espanhol | CUMED | ID: cum-78990
6.
JMIR Res Protoc ; 9(11): e23117, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33196449

RESUMO

BACKGROUND: The COVID-19 pandemic has become a public health emergency of international concern; it has not only threatened people's physical health but has also affected their mental health and psychological well-being. It is necessary to develop and offer strategies to reduce the psychological impact of the outbreak and promote adaptive coping. OBJECTIVE: This study protocol aims to describe a self-administered web-based intervention (Mental Health COVID-19) based on the principles of positive psychology supported by elements of cognitive behavioral therapy and behavioral activation therapy to reduce the symptoms of anxiety and depression and increase positive emotions and sleep quality during and after the COVID-19 outbreak through a telepsychology system. METHODS: A randomized controlled clinical superiority trial with two independent groups will be performed, with intrasubject measures at four evaluation periods: pretest, posttest, 3-month follow-up, and 6-month follow-up. Participants will be randomly assigned to one of two groups: self-administered intervention with assistance via chat or self-administered intervention without assistance via chat. The total required sample size will be 166 participants (83 per group). RESULTS: The clinical trial is ongoing. This protocol was approved by the Research Ethics Board of the Free School of Psychology-University of Behavioral Sciences (Escuela libre de Psicología-Universidad de Ciencias del Comportamiento). The aim is to publish the preliminary results in December 2020. A conservative approach will be adopted, and the size effect will be estimated using the Cohen d index with a significance level (α) of .05 (95% reliability) and a conventional 80% power statistic. CONCLUSIONS: The central mechanism of action will be to investigate the effectiveness of an intervention based on positive psychology through a web platform that can be delivered through computers and tablets, with content that has been rigorously contextualized to the Mexican culture to provide functional strategies to help the target users cope with the COVID-19 pandemic. TRIAL REGISTRATION: ClinicalTrials.gov NCT04468893; https://clinicaltrials.gov/ct2/show/NCT04468893. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/23117.

7.
Plants (Basel) ; 9(4)2020 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-32252324

RESUMO

K and N are the nutrients with the highest influence on yield and fruit quality. From this perspective, the aim of this study was to determine the effect of N as NO3-, K+ and their interactions on the yield and quality of strawberries grown under soilless conditions. A solution comprised of micronutrients based on an amended Steiner's Universal Nutrient Solution was mixed with 4 levels of K+ (5, 7, 9 and 11 mol m-3) and 3 levels of NO3- (9, 12, and 15 mol m-3) to obtain 12 treatments. The results suggest that 15 mol m-3 of NO3- in the nutrient solution produced the highest yield, but fruit with low nutraceutical quality. On the other hand, 11 mol m-3 of K+ in the nutrient solution produced the highest yield and fruit with the best nutraceutical quality. The ionic concentration of the Universal Steiner's Nutrient Solution proved to be the best nutritional option to maximize the yield and nutraceutical quality of strawberry fruit. The increase in NO3- concentration in the nutrient solution produced a higher yield of strawberries, while a higher concentration of K+ improved fruit quality, thus reaffirming the significance of nutrients within the plant functioning of this crop.

8.
PLoS One ; 13(9): e0204442, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30265725

RESUMO

Self-recovery schemes identify and restore tampering, using as a reference a compressed representation of a signal embedded into itself. In addition, audio self-recovery must comply with a transparency threshold, adequate for applications such as on-line music distribution or speech transmission. In this manuscript, an audio self-recovery scheme is proposed. Auditory masking properties of the signals are used to determine the frequencies that better mask the embedding distortion. Frequencies in the Fourier domain are mapped to the intDCT domain for embedding and extraction of reference bits for signal restoration. The contribution of this work is the use of auditory masking properties for the frequency selection and the mapping to the intDCT domain. Experimental results demonstrate that the proposed scheme satisfies a threshold of -2 ODG, suitable for audio applications. The efficacy of the scheme, in terms of its restoration capabilities, is also shown.


Assuntos
Percepção Auditiva/fisiologia , Música , Estimulação Acústica , Análise de Fourier , Humanos
9.
In. Vicente Peña, Ernesto. Medicina Interna. Diagnóstico y tratamiento. La Habana, ECIMED, 2. ed; 2016. .
Monografia em Espanhol | CUMED | ID: cum-63174
10.
In. Vicente Peña, Ernesto. Medicina Interna. Diagnóstico y tratamiento. La Habana, ECIMED, 2. ed; 2016. , tab, ilus.
Monografia em Espanhol | CUMED | ID: cum-63170
11.
In. Vicente Peña, Ernesto. Medicina Interna. Diagnóstico y tratamiento. La Habana, ECIMED, 2. ed; 2016. , tab, ilus.
Monografia em Espanhol | CUMED | ID: cum-63108
12.
PLoS One ; 8(12): e81976, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24349165

RESUMO

Digital fingerprinting is a technique that consists of inserting the ID of an authorized user in the digital content that he requests. This technique has been mainly used to trace back pirate copies of multimedia content such as images, audio, and video. This study proposes the use of state-of-the-art digital fingerprinting techniques in the context of restricted distribution of digital documents. In particular, the system proposed by Kuribayashi for multimedia content is investigated. Extensive simulations show the robustness of the proposed system against average collusion attack. Perceptual transparency of the fingerprinted documents is also studied. Moreover, by using an efficient Fast Fourier Transform core and standard computer machines it is shown that the proposed system is suitable for real-world scenarios.


Assuntos
Algoritmos , Segurança Computacional , Compressão de Dados/métodos , Reconhecimento Automatizado de Padrão , Análise de Fourier , Humanos , Processamento de Sinais Assistido por Computador
13.
Molecules ; 18(11): 13471-86, 2013 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-24184818

RESUMO

The chili pepper is a very important plant used worldwide as a vegetable, as a spice, and as an external medicine. In this work, eight different varieties of Capsicum annuum L. have been characterized by their capsaicinoids content. The chili pepper fruits were cultivated in the Comarca Lagunera region in North of Mexico. The qualitative and quantitative determination of the major and minor capsaicinoids; alkaloids responsible for the pungency level, has been performed by a validated chromatographic procedure (HPLC-DAD) after a preliminary drying step and an opportune extraction procedure. Concentrations of total capsaicinoids varied from a not detectable value for Bell pepper to 31.84 mg g(-1) dried weight for Chiltepín. Samples were obtained from plants grown in experimental field and in greenhouse without temperature control, in order to evaluate temperature effect. Analysis of the two principal capsaicinoids in fruits showed that the amount of dihydrocapsaicin was always higher than capsaicin. In addition, our results showed that the content of total capsaicinoids for the varieties Serrano, Puya, Ancho, Guajillo and Bell pepper were increased with high temperature, while the content of total capsaicinoids and Scoville heat units (SHU) for the varieties De árbol and Jalapeño decreased. However, the pungency values found in this study were higher for all varieties analyzed than in other studies.


Assuntos
Capsicum/química , Cromatografia Líquida de Alta Pressão/métodos , Capsaicina/análogos & derivados , Capsaicina/química , Estrutura Molecular , Temperatura
14.
PLoS One ; 8(6): e65985, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762455

RESUMO

Collusion-resistant fingerprinting paradigm seems to be a practical solution to the piracy problem as it allows media owners to detect any unauthorized copy and trace it back to the dishonest users. Despite the billionaire losses in the music industry, most of the collusion-resistant fingerprinting systems are devoted to digital images and very few to audio signals. In this paper, state-of-the-art collusion-resistant fingerprinting ideas are extended to audio signals and the corresponding parameters and operation conditions are proposed. Moreover, in order to carry out fingerprint detection using just a fraction of the pirate audio clip, block-based embedding and its corresponding detector is proposed. Extensive simulations show the robustness of the proposed system against average collusion attack. Moreover, by using an efficient Fast Fourier Transform core and standard computer machines it is shown that the proposed system is suitable for real-world scenarios.


Assuntos
Direitos Autorais/legislação & jurisprudência , Multimídia , Reconhecimento Automatizado de Padrão/métodos , Processamento de Sinais Assistido por Computador/instrumentação , Algoritmos , Análise de Fourier , Humanos
15.
Autoimmunity ; 44(7): 576-84, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21875377

RESUMO

Systemic sclerosis (SSc) shows variable clinical expression among different ethnic groups. Herein, we describe the clinical features, prevalence of organ involvement, and autoantibody profile in Mexican Mestizo SSc patients and we compare them with patients from other ethnic groups.We included 139 SSc patients. They underwent clinical evaluation and were tested for antinuclear antibodies (ANA), anticentromere antibodies (ACA), anti-topoisomerase I, anti-RNA polymerase III, anti-U1 RNP, anti-U3 RNP, anti-U11/U12 RNP, anti-Th/To, anti-PM-Scl, anti-Ku, antinucleosome, anti-double-stranded DNA (dsDNA), anti-Sm, anti-SSA, and anti-SSB antibodies. Female predominance (93.5%) was noted; 56.8% of patients had limited cutaneous SSc; 91% had peripheral vascular involvement; 70% had joint involvement; 27% had musculoskeletal damage; 66% had gastrointestinal involvement; 41% had interstitial lung disease; 32% had pulmonary arterial hypertension (PAH); 11% had cardiac involvement; and in 1.4% renal involvement was observed. Our patients showed lower frequency of renal crisis and higher frequency of PAH than patients from other ethnic groups; also they showed higher frequency of ACA than Japanese and African American patients, higher frequency of anti-topoisomerase I than Caucasian and African American patients, higher frequency of anti-PM-Scl and anti-Ku and lower frequency of anti-RNA Pol III than the other ethnic groups. High frequencies of antinucleosome (41%) and anti-dsDNA (63%) were identified. SSc-specific autoantibody frequencies are different in our patients and in those from other ethnic groups; associations of autoantibodies with clinical manifestations are confirmed in our patients. Ethnicity and the interaction of gene and environmental factors may influence the clinical picture and autoantibody profile in SSc patients.


Assuntos
Autoanticorpos/imunologia , Escleroderma Sistêmico/imunologia , Adulto , Autoanticorpos/sangue , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Hispânico ou Latino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Prevalência , Escleroderma Sistêmico/epidemiologia
16.
Rev. colomb. obstet. ginecol ; 61(3): 262-266, jul.-sept. 2010.
Artigo em Espanhol | LILACS | ID: lil-563689

RESUMO

Introducción: la traquelectomía radical (TR) es una técnica quirúrgica utilizada en estadios precoces del cáncer de cérvix en aquellas mujeres que desean conservar la capacidad reproductiva. Los embarazos posteriores a esta técnica quirúrgica pueden desencadenar complicaciones obstétricas. El presente artículo tiene como objetivo hacer una revisión de la literatura en relación al pronóstico obstétrico de estas pacientes. Metodología: en este estudio se presenta un caso clínico. Posteriormente, se realiza una búsqueda en las bases de datos MEDLInE, vía PubMed, y Cochrane con las palabras clave “cáncer de cérvix”, “traquelectomía radical”, “embarazo” y “complicaciones obstétricas”. Resultados: se evaluó un total de 17 artículos que comprendieron revisiones, artículos de opinión y casos clínicos. Conclusión: la preservación de la fertilidad en estadios precoces del cáncer de cérvix mediante la traquelectomía radical está adquiriendo cada vez mayor aceptación a medida que se publican más casos en la literatura. Los resultados obstétricos parecen ser cada vez más favorables aunque son más numerosas las complicaciones en comparación con la población general.


Introduction: radical trachelectomy (TR) is a surgical technique which is used in the early stages of cervical cancer in females wishing to conserve their reproductive ability. Pregnancies following this surgical technique having been applied could trigger obstetric complications. This article was thus aimed at reviewing the literature related to these patients’ obstetric prognosis. Methodology: a clinical case is presented. A literature search was made in MEDLInE databases, via PubMed and Cochrane, using the following key words: “cervical cancer”, “radical trachelectomy”, “pregnancy”, “obstetric complications”. Results: 17 articles were evaluated, covering review articles, articles expressing opinion and clinical cases. Conclusion: preserving fertility in early stages of cervical cancer by radical trachelectomy is increasingly acquiring more acceptance as more cases are published in the literature. Obstetric results seem to be becoming more favorable even though complications are becoming more numerous compared to incidence in the general population.


Assuntos
Humanos , Adulto , Feminino , Gravidez , Neoplasias do Colo do Útero
17.
Plant Physiol Biochem ; 48(8): 724-30, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20447830

RESUMO

Capsicum annuum var. aviculare to Tarahumara and Papago Indians and farmers of Sonora desert is a promising biological and commercial value as a natural resource from arid and semiarid coastal zones. Traditionally, apply synthetic fertilizers to compensate for soil nitrogen deficiency. However, indiscriminate use of these fertilizers might increase salinity. The inoculation by plant growth promoting bacteria (PGPB) and arbuscular mycorrhizal fungi (AMF) represents an alternative as potential bio fertilizer resources for salty areas. Seeds ecotypes from four areas of Sonora desert (Mazocahui, Baviacora, Arizpe, La Tortuga), in order to inoculate them with one species of PGPB and AMF. Two germination tests were carried out to study the effect of salinity, temperature regime (night/day) and inoculation with PGPB and AMF growth factors measured on germination (percentage and rate), plant height, root length, and produced biomass (fresh and dry matter). The results indicated that from four studied ecotypes, Mazocahui was the most outstanding of all, showing the highest germination under saline and non-saline conditions. However, the PGPB and AMF influenced the others variables evaluated. This study is the first step to obtain an ideal ecotype of C. a. var. aviculare, which grows in the northwest of México and promoting this type of microorganisms as an efficient and reliable biological product. Studies of the association of PGPB and AMF with the C. a. var. aviculare-Mazocahui ecotype are recommended to determine the extent to which these observations can be reproduced under field conditions.


Assuntos
Bactérias/crescimento & desenvolvimento , Capsicum/crescimento & desenvolvimento , Micorrizas/crescimento & desenvolvimento , Raízes de Plantas/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Adaptação Fisiológica/efeitos dos fármacos , Biomassa , Capsicum/classificação , Capsicum/microbiologia , Germinação/efeitos dos fármacos , Klebsiella pneumoniae/crescimento & desenvolvimento , México , Raízes de Plantas/microbiologia , Salinidade , Cloreto de Sódio/farmacologia , Especificidade da Espécie , Temperatura
18.
Interciencia ; Interciencia;31(3): 226-230, mar. 2006. tab, graf
Artigo em Espanhol | LILACS | ID: lil-449248

RESUMO

La adopción de sistemas de labranza reducida y utilización de abonos verdes en áreas de riego en México ha sido muy limitada, a pesar de múltiples reportes sobre los beneficios de tales prácticas. La preparación convencional de suelos, con un paso de arado, uno o dos rastreos y escasa incorporación de residuos orgánicos, ha propiciado una severa degradación del suelo, sobre todo en zonas áridas de baja fertilidad natural y principalmente en el contenido de materia orgánica (MO). Se evaluó el efecto de labranza convencional, reducida y mínima, y del uso de abono verde, en la recuperación de fertilidad en un suelo árido con pobres características nutrimentales y contenido de MO del 0,54 por ciento. Como abono verde se utilizó el frijol dolichos Lablab purpureus en dos condiciones (con o sin incorporación) y se consideraron dos fechas de muestreo. Las muestras de suelo a 0-30cm mostraron incrementos (promedio) de MO (0,12 por ciento), K (12,64mgúkg-¹) y actividad microbiana (36,6 por ciento) en el segundo muestreo con respecto al primero, previo a la incorporación del abono verde. Las parcelas con incorporación de abono tuvieron incrementos de MO (0,17 por ciento), K (12,46mgúkg-¹) y tasa de respiración (48,3 por ciento) en los primeros 10cm de suelo, respecto a las parcelas sin incorporación. Las variables estudiadas fueron analizadas en conjunto por correlación canónica (ACC) utilizando el programa CANOCO, cuyos resultados muestran un incremento significativo tras la incorporación del abono verde con respecto al contenido de carbón mineralizado, macronutrientes (N, P y K) y MO


Assuntos
Fármacos para a Fertilidade , Respiração , Solo , Biologia
19.
Interciencia ; Interciencia;28(7): 415-420, jul. 2003. tab
Artigo em Espanhol | LILACS | ID: lil-356813

RESUMO

Se evaluó el impacto de cultivos intercalados con algodonero (Gossypium hirsutum) en la densidad de insectos hemípteros depredadores. Además se pretendió encontrar evidencias de interdepredación. Los cultivos intercaladados con algodonero fueron canola (Brassica napus), alfalfa (medicago sativa), veza (Vicia villosa) y esparceta (Onobrychis viciifolia). La densidad fue presentada como promedio de individuos en 30m lineales (i/30m). Se establecieron también parcelas de algodonero, sin cultivos intercalados, bajo tratamientos con productos para control de gusano rosado (Pectinophora gossypiella) y un testigo sin ningún tipo de control. Los cultivos intercalados al algodonero promovieron densidades altas de depredadores, existiendo migración significativa de éstos al algodonero intercalado al final de la temporada. Geocoris spp. mostró sumayor densidad en veza, con un aumento gradual hasta el muestreo final en sus estados de ninfa y adulto. Nabis spp. también fue más abundante en veza, como ninfa al principio y como adulto a la mitad de la temporada, y disminuyó posteriormente su densidad en todos los cultivos, siendo en la segunda mitad del ciclo superior en alfalfa y esparceta. Orius spp. mantuvo su mayor densidad en alfalfa, excepto en el último muestreo, cuando fue mayor en el algodonero intercalado. Una significativa reducción de Orius spp. en proporción al incremento de Geocoris spp., así como otros resultados, proporcionaron indicios de interdepredación de Geocoris spp. hacia Orius spp. e incluso hacia Nabis spp. El tratamiento insecticida químico presentó los valores más bajos para todas las especies evaluadas.


Assuntos
Produção Agrícola
20.
Interciencia ; Interciencia;27(8): 417-421, ago. 2002. tab, graf
Artigo em Espanhol | LILACS | ID: lil-338643

RESUMO

El Chile (Capsicum annuum L.) es una de las especies cultivadas más importantes en México y muchos otros países. Uno de los problemas más importantes que actualmente enfrenta no sólo este cultivo, sino la agricultura en general, es la pérdida de la fertilidad del suelo. Conociendo la importancia de la materia orgánica en el suelo, se realizó un experimento con la variedad de chile Anaheim TMR 23 en un suelo yermosol háplico. Como tratamiento, se aplicaron tres dosis de composta (25, 50 y 100t-ha-1). Estos tratamientos se compararon con una parcela testigo sin la aplicación de composta, con el fin de determinar la dosis para obtener una mejor producción. Se evaluó en el suelo la humedad del suelo, capacidad de campo, humedad aprovechable, porosidad total, densidad aparente, densidad real y punto de marchitamiento permanente. Los resultados mostraron que las dosis mayores mejoraron todas estas variables físicas del suelo. No se encontraron diferencias significativas (P=0,05) en lo que respecta al rendimiento, sin embargo, se muestra una tendencia de mayor rendimiento en la dosis de 25t-ha-1. La mayor producción de frutos sí presentó diferencias significativas (P=0,05) y correspondió a la dosis de 25t-ha-1. Con base en estos resultados se recomienda la aplicación de dicha dosis para este tipo de suelos yermosol háplico para el cultivo del chile, mientras que las dosis mayores (50 y 100t-ha-1) se recomiendan para mejorar las características físicas del suelo en condiciones áridas en plazos cortos de tiempo


Assuntos
Produção Agrícola , Zona Árida , Capsicum , Solo , Umidade do Solo , Poluição Ambiental , Tratamento do Solo , Fármacos para a Fertilidade , México , Ciência
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