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1.
Artículo en Inglés | MEDLINE | ID: mdl-38666361

RESUMEN

BACKGROUND: Physical decline due to aging has been associated with the risk of falls. Minimum toe clearance (MTC) is a gait parameter that might play a role in the mechanism of tripping and falling. However, it is unclear if there are any sex-related effects regarding MTC as people age. The present study investigated if there are sex-related differences in MTC in older active adults. METHODS: Twenty-three females and 23 males (F: 65.5 ± 4.8 yrs; M: 61.9 ± 5.2 yrs) walked on a treadmill at a preferred walking speed, while kinematic data were obtained at a sampling frequency of 100 Hz and up-sampled to 120 and 240Hz. MTC was calculated from the kinematics data and evaluated concerning its magnitude (i.e., MTC and MTC/leg length), the time between left/right MTC (i.e., T-MTC), amount of variability (i.e., CV and CVm), and temporal structure of variability i.e., the complexity of the time series (i.e., MTC α, T-MTC α). RESULTS: No sex effects were found for MTC/leg length, for the amount of variability (i.e., CV and CVm), and for the complexity of the time series (MTC α, T-MTC α). However, females exhibited significantly lower MTC and T-MTC after adjusting for walking speed, mass, and age as covariates. CONCLUSIONS: The reduced MTC in females suggests a potential sex-related disparity in the risk of tripping and falling among active older adults.

2.
Int J Mol Sci ; 24(24)2023 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-38139377

RESUMEN

Bladder cancer (BC) stands as one of the most prevalent urological malignancies, with over 500 thousand newly diagnosed cases annually. Treatment decisions in BC depend on factors like the risk of recurrence, the type of tumor, and the stage of the disease. While standard therapeutic approaches encompass transurethral resection of the bladder tumor, radical cystectomy, and chemo- or immunotherapy, these methods exhibit limited efficacy in mitigating the aggressive and recurrent nature of bladder tumors. To overcome this challenge, it is crucial to develop innovative methods for monitoring and predicting treatment responses among patients with BC. Metabolomics is gaining recognition as a promising approach for discovering biomarkers. It has the potential to reveal metabolic disruptions that precisely reflect how BC patients respond to particular treatments, providing a revolutionary method to improve accuracy in monitoring and predicting outcomes. In this article, we present a comprehensive review of studies employing metabolomics approaches to investigate the metabolic responses associated with different treatment modalities for BC. The review encompasses an exploration of various models, samples, and analytical techniques applied in this context. Special emphasis is placed on the reported changes in metabolite levels derived from these studies, highlighting their potential as biomarkers for personalized medicine in BC.


Asunto(s)
Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/patología , Vejiga Urinaria/patología , Cistectomía , Metabolómica/métodos , Biomarcadores
3.
Biomedicines ; 11(9)2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37760774

RESUMEN

Alzheimer's disease is the most prevalent neurodegenerative disorder and affects the lives not only of those who are diagnosed but also of their caregivers. Despite the enormous social, economic and political burden, AD remains a disease without an effective treatment and with several failed attempts to modify the disease course. The fact that AD clinical diagnosis is most often performed at a stage at which the underlying pathological events are in an advanced and conceivably irremediable state strongly hampers treatment attempts. This raises the awareness of the need to identify and characterize the early brain changes in AD, in order to identify possible novel therapeutic targets to circumvent AD's cascade of events. One of the most auspicious targets is mitochondria, powerful organelles found in nearly all cells of the body. A vast body of literature has shown that mitochondria from AD patients and model organisms of the disease differ from their non-AD counterparts. In view of this evidence, preserving and/or restoring mitochondria's health and function can represent the primary means to achieve advances to tackle AD. In this review, we will briefly assess and summarize the previous and latest evidence of mitochondria dysfunction in AD. A particular focus will be given to the recent updates and advances in the strategy options aimed to target faulty mitochondria in AD.

4.
J Thorac Imaging ; 38(2): 104-112, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36162074

RESUMEN

PURPOSE: To assess if dual-energy computed tomographic pulmonary angiography (DECTPA) derived lobar iodine quantification can provide an accurate estimate of lobar perfusion in patients with severe emphysema, and offer an adjunct to single-photon emission CT perfusion scintigraphy (SPECT-PS) in assessing suitability for lung volume reduction (LVR). MATERIALS AND METHODS: Patients with severe emphysema (forced expiratory volume in 1 s <49% predicted) undergoing evaluation for LVR between May 2018 and April 2020 imaged with both SPECT-PS and DECTPA were included in this retrospective study. DECTPA perfused blood volume maps were automatically segmented and lobar iodine mass was estimated and compared with lobar technetium (Tc99m) distribution acquired with SPECT-PS. Pearson correlation and Bland-Altman analysis were used for intermodality comparison between DECTPA and SPECT-PS. Univariate and adjusted multivariate linear regression were modelled to ascertain the effect sizes of possible confounders of disease severity, sex, age, and body mass index on the relationship between lobar iodine and Tc99m values. Effective radiation dose and adverse reactions were recorded. RESULTS: In all, 123 patients (64.5±8.8 y, 71 men; mean predicted forced expiratory volume in 1 s 32.1 ±12.7%,) were eligible for inclusion. There was a linear relationship between lobar perfusion values acquired using DECTPA and SPECT-PS with statistical significance ( P <0.001). Lobar relative perfusion values acquired using DECTPA and SPECT-PS had a consistent relationship both by linear regression and Bland-Altman analysis (mean bias, -0.01, mean r2 0.64; P <0.0001). Individual lobar comparisons demonstrated moderate correlation ( r =0.79, 0.78, 0.84, 0.78, 0.8 for the right upper, middle, lower, left upper, and lower lobes, respectively, P <0.0001). The relationship between lobar iodine and Tc99m values was not significantly altered after controlling for confounders including symptom and disease severity, age, sex, and body mass index. CONCLUSIONS: DECTPA provides an accurate estimation of lobar perfusion, showing good agreement with SPECT-PS and could potentially streamline preoperative assessment for LVR.


Asunto(s)
Enfisema , Enfisema Pulmonar , Masculino , Humanos , Neumonectomía , Estudios Retrospectivos , Enfisema Pulmonar/cirugía , Pulmón/cirugía , Enfisema/cirugía , Perfusión , Angiografía
5.
Sci Rep ; 12(1): 12886, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35902719

RESUMEN

In this paper, we present the results of a 6-year experiment in space that studied the effects of radiation in Gallium Nitride (GaN) electronics in geostationary orbit. Four GaN transistors in a Colpitts oscillator configuration were flown in the Component Technology Test-Bed aboard the Alphasat telecommunication satellite. A heuristic analysis was performed by observing the variation in the power output of the oscillators with the total ionizing dose gathered during the mission. The total ionizing dose was measured with a Radiation Sensing Field Effect Transistors (RadFET) placed close to the GaN devices. The experiment showed that GaN is a robust technology that can be used in the space radiation environment of a geostationary orbit. The work presented here starts with a brief introduction of the subject, the motivation, and the main goal. This is followed by the description of the experimental setup, including the details of the oscillator design and simulations, as well as the implementation of the test-bed and the Components Technology Test-Bed. Finally, the results obtained during the 6 years of experience in space are discussed.

6.
Front Psychol ; 13: 861263, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35783727

RESUMEN

The main objective of this study was to analyze the influence of tactical and situational variables on offensive sequences during elite European handball matches. A sample of 55 games and 5.857 offensive sequences from the European Handball Federation Champions League, the selected teams were classified as the top eight teams in the league, were analyzed using X 2 and logistic regression analyses. Results indicated that positional attacks [odds ratio (OR) = 0.34; 95% CI: 0.28-0.42; p < 0.001] and fast attacks (OR = 0.46; 95% CI: 0.36-0.57; p < 0.001) decreased the probability of success for an offensive sequence by 66% and 54% when compared with counterattacks. Offensive sequences that start in the attacking zone seem to be less effective (~78%) than those that start from a situation of "ball in center." Additionally, offensive sequences that finished in the defensive zone of the observed team were 3.19 times more effective than those that ended before the 9 m zone. We concluded that compared with offensive sequences where the shot is performed from the 9 m zone, the chances of an offensive sequence ending successfully are 3.65, 3.60, and 2.21 times higher, for offensive sequences where the shot is performed from 9 m, 6 m, and the defensive zone, respectively. On the other hand, many variables seem to impact the performance of handball teams. Nevertheless, a significant challenge remains, and more research needs to be conducted to analyze the obstacles that teams need to overcome while attacking in the most effective way possible.

7.
Rev. andal. med. deporte ; 15(2): 38-42, Jun. 2022. tab, graf
Artículo en Inglés | IBECS | ID: ibc-209900

RESUMEN

Objective: Evaluate the anthropometric characteristics of male rink hockey goalkeepers, and to compare the variation according to their competitive level (international vs. non-international). Methods: Body mass, stature, sitting height, arm span, waist and hip circumferences and four skinfold measurements (triceps, medial calf, subscapular and supraspinale) of international (n = 12) and non-international (n = 23) goalkeepers were taken. Body mass index (BMI, weight/height 2), the sum of four skinfolds, the sitting height/stature ratio, waist/hip ratio and the relative arm span were also calculated. Results: International rink hockey goalkeepers have lower values of subcutaneous adiposity for the sum of the four skinfolds (P = 0.042; d= 0.76) particularly in the triceps (P = 0.016; d = 0.87) and are taller than non-international goalkeepers (+3.8 cm [2.2%]; 180.5 ± 7.0 vs. 176.6 ± 4.8 cm; t =1.920; P = 0.064; d = 0.65). Conclusion: The findings could indicate that stature and body fat may have important implications for scouts regarding the selection process and coaches that work with players on developing performance. Future research should investigate the extent to which different anthropometric measures influence performance in rink hockey goalkeepers.(AU)


Objetivo: Evaluar las características antropométricas de los porteros masculinos de hockey sobre patines y comparar las diferencias según su nivel competitivo (internacional vs. no internacional). Métodos: Se midieron la masa corporal, altura, altura sentada, envergadura, circunferencia de cintura y cadera y cuatro pliegues cutáneos (tríceps, pantorrilla medial, subescapular y suprailíaco) de porteros internacionales (n = 12) y no internacionales (n = 23). También se calculó el índice de masa corporal (IMC, peso/altura 2), la suma de los cuatro pliegues de grasa subcutánea, la relación altura/sentado, la relación cintura/cadera y la envergadurarelativa. Resultados: Los porteros de hockey sobre patines internacionales presentan valores más bajos de adiposidad subcutánea para la suma de los cuatropliegues de grasa subcutánea (P = 0.042; d = 0.76) principalmente en el pliegue del tríceps (P = 0.016; d = 0.87) y son más altos do que los porteros no internacionales (+3.8 cm [2.2%]; 180.5 ± 7.0 vs. 176.6 ± 4.8 cm; t = 1.920; P = 0.064; d = 0.65).Conclusión: Los resultados de este estudio pueden indicar que la altura y la grasa corporal pueden tener implicaciones importantes con respecto al proceso de selección tanto para los scouts como para los entrenadores que trabajan con los jugadores en el desarrollo del rendimiento. Estudios futuros deberían centrarse en investigar hasta qué punto las diferentes medidas antropométricas influyen en el rendimiento de los porteros de hockey sobre patines.(AU)


Objetivo: Avaliar as características antropométricas dos guarda-redes masculinos de hóquei em patins e comparar as diferenças de acordo com seu nível competitivo (internacional vs. não internacional). Métodos: Foi medida a Massa corporal, estatura, altura sentada, envergadura, circunferências da cintura e quadril e quatro pregas de gordura subcutânea (trícipital, geminal média, subescapular e suprailíaca) de guarda-redes internacionais (n = 12) e não internacionais (n = 23). O índice de massa corporal (IMC, peso/altura 2 ), a soma das quatro pregas de gordura subcutânea, a relação altura/estatura sentada, relação cintura/quadril e a envergadura relativa também foram calculadas. Resultados: Os guarda-redes internacionais apresentam menores valores de adiposidade subcutânea para a soma das quatro pregas de gordura subcutânea (P = 0,042; d = 0,76) principalmente na prega tricípital (P = 0.016; d= 0.87) e são mais altos do que os guarda-redes não internacionais (+3.8 cm [2.2%]; 180.5 ± 7.0 vs. 176.6 ± 4.8 cm; t = 1.920; P = 0.064; d = 0. 65). Conclusão: Os resultados deste estudo podem indicar que estatura e a gordura corporal podem ter implicações importantes no que diz respeito ao processo de seleção tanto para olheiros e treinadores que trabalham com jogadores no desenvolvimento de desempenho. Futuros estudos devem centrar-se em investigar até que ponto diferentes medidas antropométricas influenciam o desempenho dos guarda-redes de hóquei em patins.(AU)


Asunto(s)
Humanos , Masculino , Hockey , Antropometría , Adiposidad , Conducta Competitiva , Índice de Masa Corporal , Grosor de los Pliegues Cutáneos , Medicina Deportiva , Deportes
8.
PLoS One ; 16(12): e0260997, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34965248

RESUMEN

Breeding programs of the species Coffea canephora rely heavily on the significant genetic variability between and within its two varietal groups (conilon and robusta). The use of hybrid families and individuals has been less common. The objectives of this study were to evaluate parents and families from the populations of conilon, robusta, and its hybrids and to define the best breeding and selection strategies for productivity and disease resistance traits. As such, 71 conilon clones, 56 robusta clones, and 20 hybrid families were evaluated over several years for the following traits: vegetative vigor, incidence of rust and cercosporiosis, fruit ripening time, fruit size, plant height, canopy diameter, and yield per plant. Components of variance and genetic parameters were estimated via residual maximum likelihood (REML) and genotypic values were predicted via best linear unbiased prediction (BLUP). Genetic variability among parents (clones) and hybrid families was detected for most of the evaluated traits. The Mulamba-Rank index suggests potential gains up to 17% for the genotypic aggregate of traits in the hybrid population. An intrapopulation recurrent selection within the hybrid population would be the best breeding strategy because the genetic variability, narrow and broad senses heritabilities and selective accuracies for important traits were maximized in the crossed population. Besides, such strategy is simple, low cost and quicker than the concurrent reciprocal recurrent selection in the two parental populations, and this maximizes the genetic gain for unit of time.


Asunto(s)
Coffea/genética , Resistencia a la Enfermedad/genética , Hibridación Genética , Fitomejoramiento , Enfermedades de las Plantas/genética , Carácter Cuantitativo Heredable , Ambiente , Genotipo , Funciones de Verosimilitud
9.
J Chem Inf Model ; 61(11): 5343-5361, 2021 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-34699719

RESUMEN

In the past few years, de novo molecular design has increasingly been using generative models from the emergent field of Deep Learning, proposing novel compounds that are likely to possess desired properties or activities. De novo molecular design finds applications in different fields ranging from drug discovery and materials sciences to biotechnology. A panoply of deep generative models, including architectures as Recurrent Neural Networks, Autoencoders, and Generative Adversarial Networks, can be trained on existing data sets and provide for the generation of novel compounds. Typically, the new compounds follow the same underlying statistical distributions of properties exhibited on the training data set Additionally, different optimization strategies, including transfer learning, Bayesian optimization, reinforcement learning, and conditional generation, can direct the generation process toward desired aims, regarding their biological activities, synthesis processes or chemical features. Given the recent emergence of these technologies and their relevance, this work presents a systematic and critical review on deep generative models and related optimization methods for targeted compound design, and their applications.


Asunto(s)
Aprendizaje Profundo , Teorema de Bayes , Diseño de Fármacos , Descubrimiento de Drogas , Redes Neurales de la Computación
10.
Rev. Enferm. Atual In Derme ; 95(36): 1-9, Out-Dez. 2021.
Artículo en Inglés, Portugués | BDENF - Enfermería | ID: biblio-1373694

RESUMEN

Objetivo: analisar, conhecer sobre o acolhimento de Travestis e Transexuais na Atenção Primária à Saúde. Métodos: trata-se de uma pesquisa bibliográfica de caráter exploratório com abordagem qualitativa, na qual realizou-se uma busca no período de março a junho de 2020 em base de dados confiáveis, em português, dentre os quais Scientifc Electronic Library Online Brasil (SciELO), Google Scholar e o site do Ministério da Saúde podem ser citados, dentre outros periódicos de referência na área.Resultados:após análise detalhada das publicações, verificou-se 16 publicações exploravam realmente o tema em questão, sendo utilizados para a construção da pesquisa. Considerações Finais: há um método principal para que o acolhimento seja qualificado e holístico, que é acapacitação do enfermeiro juntamente com a educação continuada para que ele ajude a mudar a realidade da vida do público Transno âmbito de saúde.


Objective: to analyze and learn about the reception of Transvestites and Transsexuals in Primary Health Care. Methods: this is an exploratory bibliographic research with a qualitative approach, in which a search was carried out from March to June 2020 in reliable database, in Portuguese, among which Scientifc Electronic Library Online Brazil (SciELO), Google Scholar and the Ministry of Health website can be cited, among other reference periodicals in the area. Results: after detailed analysis of the publications, it was found that 16 publications actually explored the topic in question, being used for the construction of the research. Final Considerations: there is a main method for the reception to be qualified and holistic, which is the training of nurses along with continuing education so that they help change the reality of life for the Trans public in the health field.


Asunto(s)
Humanos , Masculino , Femenino , Grupo de Atención al Paciente , Atención Primaria de Salud , Enfermería , Acogimiento , Personas Transgénero
11.
Front Psychol ; 11: 547110, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33071863

RESUMEN

The purpose of this study was to determine differences related to the offensive process between winning and losing teams among teams participating in the European Handball Federation Champions League (EHFCL) in 55 matches across five seasons. The key indicators used in this study are the offensive actions, team possession type and the zones of the field, goals, and shooting effectiveness. A total of 34 indicators were analyzed and compared using Mann-Whitney U tests. Sixteen key indicators are identified to confirm differences both from the aspect of the collective game in terms of assists (9.10 ± 2.75 vs. 7.29 ± 2.65), goals of positional attack (21.38 ± 4.60 vs. 18.20 ± 3.62) and from the aspect of individual goals from 6 m (16.67 ± 3.98 vs. 13.64 ± 3.70), and the effectiveness of shots (68.19 ± 6.83 vs. 59.41 ± 6.33). Winning teams performed better regarding the variables that defined the effectiveness of offensive shots, especially successful positioned attacks and fast attacks. They also had a greater number of assists. The profiles of the most successful teams can help coaches and practitioners to achieve better performances adjusting the training process according the performance indicators that seem to lead more often to success.

12.
Vaccines (Basel) ; 8(3)2020 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-32933148

RESUMEN

The effects of the abiotic inducers ß-glucan, extracted from Shiitake (Lentinula edodes), BFIICaB® (Kappaphycus alvarezii) and BKPSGII® (K. alvarezii X Sargassum sp.) on tomato plants infected with Fusarium oxysporum f. sp. lycopersici (FOL) were evaluated through the activity of enzymes related to the induction of resistance at 5 and 10 days after inoculation (DAI). Tomato plants (21 days old, after germination) were inoculated with the pathogen conidia suspension and sprayed with 0.3% aqueous solutions of the inducers. The activities of the enzymes ß-1,3-glucanase, peroxidase and phenylalanine ammonia lyase (PAL) were evaluated in fresh tomato leaves collected at 5 and 10 DAI. In all treatments, peroxidase showed the highest enzymatic activity, followed by ß-1,3-glucanase and PAL. Between the seaweeds, the inducers extracted from the red alga Kappaphycus alvarezii (BFIICaB®) promoted the highest enzymatic activity. The exception was BKPSGII® (K. alvarezii X Sargassum sp.) where the influence of Sargassum sp. resulted in higher peroxidase activity (4.48 Δab600 mg P-1 min-1) in the leaves, 10 DAI. Both the red seaweed K. alvarezii and the brown alga Sargassum sp. promoted activities of ß-1,3-glucanase, peroxidase and PAL.

14.
J Surg Oncol ; 121(5): 730-742, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31845348

RESUMEN

BACKGROUND: Approximately 70% of cancer-related deaths occur in low- and middle-income countries. In addition to social and racial inequalities, treatment options in these countries are usually limited because of the lack of trained staff and equipment, limited patient access to health services, and a small number of clinical guidelines. OBJECTIVES: The Brazilian Society of Surgical Oncology developed this guideline to address these barriers and guide physicians treating patients with endometrial cancer (EC) in regions with limited resources and few specialized centers. METHODS: The guideline was prepared from 10 January to 25 October 20192019 by a multidisciplinary team of 56 experts to discuss the main obstacles faced by EC patients in Brazil. Thirteen questions considered critical to the surgical treatment of these patients were defined. The questions were assigned to groups that reviewed the literature and drafted preliminary recommendations. Following a review by the coordinators and a second review by all participants, the groups made final adjustments for presentations in meetings, classified the level of evidence, and voted on the recommendations. RESULTS: For all questions including staging, fertility spearing treatment, genetic testing, sentinel lymph node use, surgical treatment, and other clinical relevant questions, major agreement was achieved by the participants, always using accessible alternatives. CONCLUSIONS: It is possible to provide adequate treatment for most EC patients in resource-limited areas, but the first option should be referral to specialized centers with more resources.


Asunto(s)
Países en Desarrollo , Neoplasias Endometriales/cirugía , Accesibilidad a los Servicios de Salud , Brasil , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Continuidad de la Atención al Paciente , Diagnóstico por Imagen , Neoplasias Endometriales/patología , Femenino , Preservación de la Fertilidad , Humanos , Histerectomía , Escisión del Ganglio Linfático , Recurrencia Local de Neoplasia/terapia , Estadificación de Neoplasias , Neoplasias Peritoneales/secundario , Neoplasias Peritoneales/terapia , Examen Físico , Derivación y Consulta , Biopsia del Ganglio Linfático Centinela , Sociedades Médicas
15.
Arch. Clin. Psychiatry (Impr.) ; 46(1): 1-4, Jan.-Feb. 2019. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-991618

RESUMEN

Abstract Objective To describe the development of weCope, a Portuguese mobile app for people with schizophrenia. Methods The development of weCope followed 4 stages: I-102 people with psychotic disorders completed an online questionnaire; II-a multidisciplinary focus group was conducted among five mental health professionals; III-we developed the app; IV-9 participants used weCope during 8 weeks to assess its efficiency. Results weCope targets coping with voices, problem solving, goals setting and stress management, and results indicated that: weCope improved symptoms, sense of recovery and personal and social functioning; 59% of the participants were willing to download an application for illness self-management; professionals revealed some concerns about mHealth but enhanced the high importance to develop these apps; usability testing revealed that 89% considered weCope useful for illness self-management. However, the more years with mental illness, the less importance is given to a mobile application for this purpose. Discussion weCope was developed through a comprehensive development process and may contribute to a subjective perception of the patient's better well-being and health condition.

16.
Opt Express ; 26(23): 30837-30850, 2018 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-30469976

RESUMEN

This article aims to present, analyze and evaluate a new equalizer architecture, inspired by the butterfly equalizer used in optical communication, based on Artificial Neural Networks (ANN) of the Multi-Layer Perceptron (MLP) type for nonlinear systems with two-dimensional modulation named the Butterfly Neural Equalizer (NE-Butterfly). The NE-Butterfly is intended to equalize any channel that has real or complex taps, whether linear or nonlinear. Simulation results are presented for different types of nonlinear fiber optic channels with complex and real taps, also containing inter symbolic interference and additive noise. The results are compared with other neural equalizers in the literature with the objective of validating the performance of the NE-Butterfly, which stands out as having the overall best performance against the ones it was compared to.

17.
Sensors (Basel) ; 18(10)2018 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-30347826

RESUMEN

This work proposes an adaptive beamforming scheme applied to time domain, pre-FFT (Fast Fourier Transformation), Orthogonal Frequency-Division Multiplexing (OFDM) systems. This scheme improves the performance and the capacity of OFDM systems, using a supervised adaptive algorithm, with frequency domain multiplexed pilots of the OFDM system as a reference. The simplicity of the proposed structure, as well as the method used to obtain reference signals for the adaptive beamforming, are essential aspects that distinguish this paper from other publications. Details on the operation of the proposed scheme, as well as the performance curves, are presented in this manuscript. The proposal investigated here allows a significant reduction in the guard interval of the OFDM system, thereby increasing its robustness or transmission capacity.

18.
Appl Opt ; 57(24): 6866-6875, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30129571

RESUMEN

A numerical simulation tool is reported for nanometer thin and inhomogeneous immobilized protein films on gold in aqueous solution. It allows for the first time, to the best of our knowledge, the simultaneous assessment of refractive index, film thickness, and surface coverage. The model relies on and combines the convective diffusion equation, the Langmuir adsorption isotherm, and the Helmholtz equation, with appropriate boundary conditions. These three differential equations were jointly solved using a multiphysics software. The physical film parameters were extracted employing an optimization procedure for immobilized bovine serum albumin, hemoglobin, and neutravidin films. The relatively good agreement between the extracted values for the refractive index, film thickness, and surface coverage and the corresponding values reported in the open literature show the correctness of the proposed methodology.


Asunto(s)
Oro/química , Modelos Teóricos , Nanopartículas/química , Proteínas/química , Electricidad Estática , Adsorción , Microscopía/métodos
19.
Front Plant Sci ; 9: 1934, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30671077

RESUMEN

Genomic Selection (GS) has allowed the maximization of genetic gains per unit time in several annual and perennial plant species. However, no GS studies have addressed Coffea arabica, the most economically important species of the genus Coffea. Therefore, this study aimed (i) to evaluate the applicability and accuracy of GS in the prediction of the genomic estimated breeding value (GEBV); (ii) to estimate the genetic parameters; and (iii) to evaluate the time reduction of the selection cycle by GS in Arabica coffee breeding. A total of 195 Arabica coffee individuals, belonging to 13 families in generation of F2, susceptible backcross and resistant backcross, were phenotyped for 18 agronomic traits, and genotyped with 21,211 SNP molecular markers. Phenotypic data, measured in 2014, 2015, and 2016, were analyzed by mixed models. GS analyses were performed by the G-BLUP method, using the RKHS (Reproducing Kernel Hilbert Spaces) procedure, with a Bayesian algorithm. Heritabilities and selective accuracies were estimated, revealing moderate to high magnitude for most of the traits evaluated. Results of GS analyses showed the possibility of reducing the cycle time by 50%, maximizing selection gains per unit time. The effect of marker density on GS analyses was evaluated. Genomic selection proved to be promising for C. arabica breeding. The agronomic traits presented high complexity for they are controlled by several QTL and showed low genomic heritabilities, evidencing the need to incorporate genomic selection methodologies to the breeding programs of this species.

20.
Biosci. j. (Online) ; 33(5): 1295-1304, sept./oct. 2017. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-966332

RESUMEN

The latex obtained from Jatropha curcas (physic nut) is used in traditional medicine to treat a variety of disturbs, including burns, hemorrhoids, ringworm and ulcers. Phytochemical analyses have shown that J. curcas latex contains natural compounds with therapeutic potential. In this study, the toxicity, cytotoxicity and genotoxicity effects of J. curcas latex on the root cells of Allium cepa were examined. Onion seeds and bulbs were exposed to seven different concentrations of latex and then the roots were submitted to macro and microscopic analyses. Water and sodium azide were used as negative and positive controls, respectively. The analysis of root growth showed that J. curcas crude latex or 50% diluted is highly toxic. Cytogenetic results showed that the mitotic index of the onion roots submitted to latex treatment decreased significantly compared to the negative control, which suggests that the latex is cytotoxic. High incidence of chromosome aberrations in the cells treated with J. curcas latex was observed too, indicating that the latex also presents genotoxic effect. The analyses presented in this report suggest the toxic, cytotoxic and genotoxic effects of J. curcas latex. Then, the indiscriminate use of J. curcas latex in folk medicine could bring risk to human health.


O látex obtido de Jatropha curcas (pinhão manso) é usado na medicina tradicional para tratamento de diversos distúrbios, como queimaduras, hemorroida, micose e úlcera. Análises fitoquímicas apontaram que o látex de J. curcas contém compostos naturais com potencial terapêutico. Este estudo avaliou a toxicidade, citotoxicidade e genotoxicidade do látex de J. curcas em células da raiz de Allium cepa. Sementes e bulbos de cebola foram expostos á sete diferentes concentrações de látex e, então, as raízes foram submetidas a análises macro e microscópica. Água e azida sódica foram utilizadas como controle negativo e positivo, respectivamente. A análise do comprimento das raízes mostrou que o látex de J. curcas puro e diluído a 50% é altamente tóxico. O índice mitótico das raízes de cebola submetidas ao tratamento com o látex diminuiu significativamente comparado com o controle negativo, o que sugere que o látex é citotóxico. Uma alta incidência de aberrações cromossômicas em células tratadas com o látex de J. curcas também foi observada, indicando que o látex apresenta efeito genotóxico. Essa análise sugere que o látex de J. curcas possui efeitos tóxico, citotóxico e genotóxico, sendo que o uso indiscriminado do látex de J. curcas na medicina popular pode trazer risco à saúde humana.


Asunto(s)
Plantas Medicinales , Jatropha , Genotoxicidad , Látex/toxicidad
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