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1.
Neural Netw ; 78: 75-87, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26476936

RESUMO

Very large high dimensional data are common nowadays and they impose new challenges to data-driven and data-intensive algorithms. Computational Intelligence techniques have the potential to provide powerful tools for addressing these challenges, but the current literature focuses mainly on handling scalability issues related to data volume in terms of sample size for classification tasks. This work presents a systematic and comprehensive approach for optimally handling regression tasks with very large high dimensional data. The proposed approach is based on smart sampling techniques for minimizing the number of samples to be generated by using an iterative approach that creates new sample sets until the input and output space of the function to be approximated are optimally covered. Incremental function learning takes place in each sampling iteration, the new samples are used to fine tune the regression results of the function learning algorithm. The accuracy and confidence levels of the resulting approximation function are assessed using the probably approximately correct computation framework. The smart sampling and incremental function learning techniques can be easily used in practical applications and scale well in the case of extremely large data. The feasibility and good results of the proposed techniques are demonstrated using benchmark functions as well as functions from real-world problems.


Assuntos
Inteligência Artificial , Conjuntos de Dados como Assunto , Aprendizado de Máquina , Redes Neurais de Computação , Algoritmos , Inteligência Artificial/tendências , Conjuntos de Dados como Assunto/tendências , Aprendizado de Máquina/tendências
2.
Genet Mol Res ; 14(2): 6744-61, 2015 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-26125883

RESUMO

Biodiversity crises have led scientists to develop strategies for achieving conservation goals. The underlying principle of these strategies lies in systematic conservation planning (SCP), in which there are at least 2 conflicting objectives, making it a good candidate for multi-objective optimization. Although SCP is typically applied at the species level (or hierarchically higher), it can be used at lower hierarchical levels, such as using alleles as basic units for analysis, for conservation genetics. Here, we propose a method of SCP using a multi-objective approach. We used non-dominated sorting genetic algorithm II in order to identify the smallest set of local populations of Dipteryx alata (baru) (a Brazilian Cerrado species) for conservation, representing the known genetic diversity and using allele frequency information associated with heterozygosity and Hardy-Weinberg equilibrium. We worked in 3 variations for the problem. First, we reproduced a previous experiment, but using a multi-objective approach. We found that the smallest set of populations needed to represent all alleles under study was 7, corroborating the results of the previous study, but with more distinct solutions. In the 2nd and 3rd variations, we performed simultaneous optimization of 4 and 5 objectives, respectively. We found similar but refined results for 7 populations, and a larger portfolio considering intra-specific diversity and persistence with populations ranging from 8-22. This is the first study to apply multi-objective algorithms to an SCP problem using alleles at the population level as basic units for analysis.


Assuntos
Algoritmos , Alelos , Conservação dos Recursos Naturais/estatística & dados numéricos , Dipteryx/genética , Variação Genética , Brasil , Conservação dos Recursos Naturais/métodos , Frequência do Gene , Heterozigoto , Humanos , Repetições de Microssatélites
3.
Plant Biol (Stuttg) ; 15(6): 1013-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23627459

RESUMO

Calmodulin (CaM), a small acidic protein, is one of the best characterised Ca(2+) sensors in eukaryotes. This Ca(2+) -regulated protein plays a critical role in decoding and transducing environmental stress signals by activating specific targets. Many environmental stresses elicit changes in intracellular Ca(2+) activity that could initiate adaptive responses under adverse conditions. We report the first molecular cloning and characterisation of a calmodulin gene, VcCaM1 (Vaccinium corymbosum Calmodulin 1), in the woody shrub, highbush blueberry. VcCaM1 was first identified as VCAL19, a gene induced by aluminium stress in V. corymbosum L. A full-length cDNA of VcCaM1 containing a 766-bp open reading frame (ORF) encoding 149 amino acids was cloned from root RNA. The sequence encodes four Ca(2+) -binding motifs (EF-hands) and shows high similarity (99%) with the isoform CaM 201 of Daucus carota. Expression analyses showed that following Al treatment, VcCaM1 message level decreased in roots of Brigitta, an Al-resistant cultivar, and after 48 h, was lower than in Bluegold, an Al-sensitive cultivar. VcCAM1 message also decreased in leaves of both cultivars within 2 h of treatment. Message levels in leaves then increased by 24 h to control levels in Brigitta, but not in Bluegold, but then decreased again by 48 h. In conclusion, VcCaM1 does not appear to be directly involved in Al resistance, but may be involved in improved plant performance under Al toxicity conditions through regulation of Ca(2+) homeostasis and antioxidant systems in leaves.


Assuntos
Alumínio/toxicidade , Mirtilos Azuis (Planta)/genética , Calmodulina/genética , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Mirtilos Azuis (Planta)/efeitos dos fármacos , Mirtilos Azuis (Planta)/fisiologia , Calmodulina/metabolismo , DNA Complementar/genética , Especificidade de Órgãos , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/fisiologia , RNA de Plantas/genética , Alinhamento de Sequência , Análise de Sequência de DNA
5.
Rev. chil. cir ; 62(6): 631-634, dic. 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-577313

RESUMO

We report a 27 years old woman presenting with hematochezia. An upper endoscopy and colonoscopy did not reveal the bleeding site. Due to persistence of bleeding, the patient was operated, finding a fibrinous secretion surrounding bowel loops and a hyper vascularized concentric papular lesion. The involved bowel loop was excised. The pathological study of the surgical piece revealed intestinal tuberculosis. The patient started treatment for extra pulmonary tuberculosis.


Reportamos el caso de una paciente de 27 años con tuberculosis extrapulmonar gastrointestinal que se manifestó clínicamente como una hemorragia digestiva baja masiva exanguinante requiriendo cirugía de urgencia, donde se realizó laparotomía exploradora con entero y colonoscopía intraoperatoria localizando lesión a nivel de intestino delgado, resecando segmento comprometido con anastomosis primaria, evolución satisfactoria sin complicaciones postoperatorias.


Assuntos
Humanos , Feminino , Adulto , Colonoscopia/métodos , Hemorragia Gastrointestinal/etiologia , Tuberculose Gastrointestinal/cirurgia , Tuberculose Gastrointestinal/complicações , Anastomose Cirúrgica , Emergências , Hemorragia Gastrointestinal/cirurgia , Intestino Delgado/patologia , Tuberculose Gastrointestinal/patologia
6.
Int. j. morphol ; 27(4): 985-988, dic. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-582039

RESUMO

We examined the status of the first metacarpal bone whose shape, fetal and post-natal development correspond to those of the thumb proximal phalanx. Galen already described this, circa 170 CE. Our radiographic data confirm that the pre-axial (radial or anterior) side of the hand matures, later than the post-axial (ulnar or posterior) side, both, pre- and post-natally. A new perspective on thumb primate and human ontogeny is discussed and comparative observations on the Evolutionary Development (EvoDevo) of the thumb and the first toe are proposed along with a nomenclature honoring Galen's original roposition.


Se analiza el estado del primer metacarpiano cuya forma y desarrollo embrionario, fetal y postnatal corresponde a los de la primera falange del pulgar. Galeno notó que éste era la primera falange del pulgar cerca de 170 DC. Esto no es un simple cambio de nomenclatura, ya que da una nueva luz a los problemas evolutivos de ontogenia (EvoDevo). Nuestros datos radiográficos confirman que el lado radial (anterior o pre-axial) de la mano madura, pre y post-natalmente, mas tardíamente que el lado cubital (posterior o post-axial). Se discuten nuevas perspectivas sobre la ontogenia y filogenia humana y de primates, y se proponen estudios comparativos del desarrollo del pulgar y del ortejo mayor.


Assuntos
Humanos , Masculino , Adolescente , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Falanges dos Dedos da Mão/crescimento & desenvolvimento , Ossos Metacarpais/crescimento & desenvolvimento , Polegar/crescimento & desenvolvimento , Desenvolvimento Ósseo , Biologia do Desenvolvimento , Falanges dos Dedos da Mão , Ossos Metacarpais , Polegar
7.
Cranio ; 17(2): 132-42, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10425940

RESUMO

This study was conducted in order to determine the effects of body position on integrated electromyographic (IEMG) activity of anterior temporal and suprahyoid muscles. The study was performed on 15 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 15 healthy subjects. IEMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the anterior temporal and suprahyoid muscles in the following body positions: standing, seated, supine, and lateral decubitus position. Insignificant changes in IEMG activity of both muscles were observed upon variations in the body position. Insignificant differences in IEMG activity were observed between patients with myogenic CMD and healthy subjects. A pattern of higher IEMG at rest and during swallowing of saliva was observed in the suprahyoid muscles than in the anterior temporal muscles, whereas during maximal clenching activity, an opposite pattern was observed. Results of the present study seem to suggest that for the anterior temporal and suprahyoid muscles there is no specific body position that could be relevant to initiate and/or to perpetuate a craniomandibular dysfunction.


Assuntos
Músculos do Pescoço/fisiopatologia , Postura , Músculo Temporal/fisiopatologia , Síndrome da Disfunção da Articulação Temporomandibular/fisiopatologia , Adulto , Análise de Variância , Força de Mordida , Estudos de Casos e Controles , Deglutição/fisiologia , Eletromiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular , Valores de Referência
8.
Rev. ADM ; 53(6): 301-6, nov.-dic. 1996. ilus
Artigo em Espanhol | LILACS | ID: lil-195471

RESUMO

El presente artículo tiene como objetivo principal conocer a fondo el proceso de reabsorción radicular externa, un problema que en gran cantidad de ocasiones, tanto el dentista de práctica general así como el especialista llegan a enfrentar durante su práctica profesional, por lo que resulta de vital importancia conocer este proceso desde su etiología, etiopatogenia, clasificación, distintos métodos de medición y evaluación, así como los factores que se asocian a esta patología, con el fin de preveerla o evitarla al máximo. El presente artículo no abarcará los distintos tipos de tratamiento, debido a la gran controversia y cantidad de información existente, lo cual ameritaría una siguiente publicación


Assuntos
Reabsorção da Raiz/classificação , Reabsorção da Raiz/etiologia , Anquilose , Extração Dentária/efeitos adversos , Má Oclusão/complicações , Ortodontia Corretiva/efeitos adversos , Raiz Dentária/patologia , Tratamento do Canal Radicular/efeitos adversos , Traumatismos Dentários/complicações
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