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1.
An Acad Bras Cienc ; 90(1): 415-424, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29641765

RESUMO

Organic fertilizers are a viable alternative to increase oilseed productivity in family agriculture systems. The study aimed to evaluate the effects of timing and placement of cattle manure and/or gliricidia (Gliricidia sepium Jacq. Walp) prunings on cotton (Gossipium hirsutum L.) and sunflower (Helianthus annuus L.) nutrient accumulation and biomass productivity. Experiments were carried out in 2010 and 2011 in Taperoá, Paraíba, Brazil. The organic fertilization treatments were: GI - gliricidia incorporated before planting; GS - gliricidia applied on surface 45 days after planting (DAP); MI + GI - manure and gliricidia incorporated before planting; MI + GS - manure incorporated before planting and gliricídia applied on the surface 45 DAP; MI - manure incorporated before planting; and T - with no organic fertilization. In 2010, treatment MI + GS increased N, P, and K accumulation in cotton (12 and 7 kg ha-1) as well as in sunflower (20 and 29 kg ha-1). In 2011, GI and GS treatments resulted in higher N, P, K accumulations in both crops. The highest cotton productivity in 2010 was obtained with MI + GS treatment (198 kg ha-1) and in 2011 with GS treatment (594 kg ha-1). For sunflower, MI + GS treatment yielded the highest productivity in 2010 (466 kg ha-1) and GI treatment in 2011 (3542 kg ha-1). GI and MI + GS treatments increased total biomass productivity for cotton and sunflower. The treatment that combined both cattle manure incorporated into the soil before planting and gliricidia applied on the surface 45 days after planting was the most viable management strategy.


Assuntos
Fabaceae/química , Fertilizantes , Gossypium/crescimento & desenvolvimento , Helianthus/crescimento & desenvolvimento , Esterco , Absorção Fisiológica/fisiologia , Animais , Biomassa , Brasil , Bovinos , Produção Agrícola/métodos , Produção Agrícola/normas , Eficiência , Solo/química , Fatores de Tempo
2.
Sensors (Basel) ; 18(7)2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-30012990

RESUMO

Technological innovations in the hardware of RGB-D sensors have allowed the acquisition of 3D point clouds in real time. Consequently, various applications have arisen related to the 3D world, which are receiving increasing attention from researchers. Nevertheless, one of the main problems that remains is the demand for computationally intensive processing that required optimized approaches to deal with 3D vision modeling, especially when it is necessary to perform tasks in real time. A previously proposed multi-resolution 3D model known as foveated point clouds can be a possible solution to this problem. Nevertheless, this is a model limited to a single foveated structure with context dependent mobility. In this work, we propose a new solution for data reduction and feature detection using multifoveation in the point cloud. Nonetheless, the application of several foveated structures results in a considerable increase of processing since there are intersections between regions of distinct structures, which are processed multiple times. Towards solving this problem, the current proposal brings an approach that avoids the processing of redundant regions, which results in even more reduced processing time. Such approach can be used to identify objects in 3D point clouds, one of the key tasks for real-time applications as robotics vision, with efficient synchronization allowing the validation of the model and verification of its applicability in the context of computer vision. Experimental results demonstrate a performance gain of at least 27.21% in processing time while retaining the main features of the original, and maintaining the recognition quality rate in comparison with state-of-the-art 3D object recognition methods.

3.
J Biol Chem ; 287(10): 7436-45, 2012 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-22235132

RESUMO

Cognitive decline in Alzheimer disease (AD) is increasingly attributed to the neuronal impact of soluble oligomers of the amyloid-ß peptide (AßOs). Current knowledge on the molecular and cellular mechanisms underlying the toxicity of AßOs stems largely from rodent-derived cell/tissue culture experiments or from transgenic models of AD, which do not necessarily recapitulate the complexity of the human disease. Here, we used DNA microarray and RT-PCR to investigate changes in transcription in adult human cortical slices exposed to sublethal doses of AßOs. The results revealed a set of 27 genes that showed consistent differential expression upon exposure of slices from three different donors to AßOs. Functional classification of differentially expressed genes revealed that AßOs impact pathways important for neuronal physiology and known to be dysregulated in AD, including vesicle trafficking, cell adhesion, actin cytoskeleton dynamics, and insulin signaling. Most genes (70%) were down-regulated by AßO treatment, suggesting a predominantly inhibitory effect on the corresponding pathways. Significantly, AßOs induced down-regulation of synaptophysin, a presynaptic vesicle membrane protein, suggesting a mechanism by which oligomers cause synapse failure. The results provide insight into early mechanisms of pathogenesis of AD and suggest that the neuronal pathways affected by AßOs may be targets for the development of novel diagnostic or therapeutic approaches.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Regulação da Expressão Gênica , Proteínas do Tecido Nervoso/biossíntese , Adulto , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/patologia , Doença de Alzheimer/terapia , Encéfalo/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos
4.
PLoS One ; 17(6): e0254736, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35772072

RESUMO

In bioinformatics, alignment is an essential technique for finding similarities between biological sequences. Usually, the alignment is performed with the Smith-Waterman (SW) algorithm, a well-known sequence alignment technique of high-level precision based on dynamic programming. However, given the massive data volume in biological databases and their continuous exponential increase, high-speed data processing is necessary. Therefore, this work proposes a parallel hardware design for the SW algorithm with a systolic array structure to accelerate the forward and backtracking steps. For this purpose, the architecture calculates and stores the paths in the forward stage for pre-organizing the alignment, which reduces the complexity of the backtracking stage. The backtracking starts from the maximum score position in the matrix and generates the optimal SW sequence alignment path. The architecture was validated on Field-Programmable Gate Array (FPGA), and synthesis analyses have shown that the proposed design reaches up to 79.5 Giga Cell Updates per Second (GCPUS).


Assuntos
Algoritmos , Biologia Computacional , Biologia Computacional/métodos , Bases de Dados Factuais , Desenho de Equipamento , Alinhamento de Sequência , Software
5.
An. acad. bras. ciênc ; 90(1): 415-424, Mar. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-886910

RESUMO

ABSTRACT Organic fertilizers are a viable alternative to increase oilseed productivity in family agriculture systems. The study aimed to evaluate the effects of timing and placement of cattle manure and/or gliricidia (Gliricidia sepium Jacq. Walp) prunings on cotton (Gossipium hirsutum L.) and sunflower (Helianthus annuus L.) nutrient accumulation and biomass productivity. Experiments were carried out in 2010 and 2011 in Taperoá, Paraíba, Brazil. The organic fertilization treatments were: GI - gliricidia incorporated before planting; GS - gliricidia applied on surface 45 days after planting (DAP); MI + GI - manure and gliricidia incorporated before planting; MI + GS - manure incorporated before planting and gliricídia applied on the surface 45 DAP; MI - manure incorporated before planting; and T - with no organic fertilization. In 2010, treatment MI + GS increased N, P, and K accumulation in cotton (12 and 7 kg ha-1) as well as in sunflower (20 and 29 kg ha-1). In 2011, GI and GS treatments resulted in higher N, P, K accumulations in both crops. The highest cotton productivity in 2010 was obtained with MI + GS treatment (198 kg ha-1) and in 2011 with GS treatment (594 kg ha-1). For sunflower, MI + GS treatment yielded the highest productivity in 2010 (466 kg ha-1) and GI treatment in 2011 (3542 kg ha-1). GI and MI + GS treatments increased total biomass productivity for cotton and sunflower. The treatment that combined both cattle manure incorporated into the soil before planting and gliricidia applied on the surface 45 days after planting was the most viable management strategy.


Assuntos
Animais , Gossypium/crescimento & desenvolvimento , Fertilizantes , Helianthus/crescimento & desenvolvimento , Fabaceae/química , Esterco , Solo/química , Fatores de Tempo , Brasil , Bovinos , Biomassa , Eficiência , Absorção Fisiológica/fisiologia , Produção Agrícola/métodos , Produção Agrícola/tendências
6.
Neurotox Res ; 18(2): 112-23, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19949915

RESUMO

2,4-Dinitrophenol (DNP) is classically known as a mitochondrial uncoupler and, at high concentrations, is toxic to a variety of cells. However, it has recently been shown that, at subtoxic concentrations, DNP protects neurons against a variety of insults and promotes neuronal differentiation and neuritogenesis. The molecular and cellular mechanisms underlying the beneficial neuroactive properties of DNP are still largely unknown. We have now used DNA microarray analysis to investigate changes in gene expression in rat hippocampal neurons in culture treated with low micromolar concentrations of DNP. Under conditions that did not affect neuronal viability, high-energy phosphate levels or mitochondrial oxygen consumption, DNP induced up-regulation of 275 genes and down-regulation of 231 genes. Significantly, several up-regulated genes were linked to intracellular cAMP signaling, known to be involved in neurite outgrowth, synaptic plasticity, and neuronal survival. Differential expression of specific genes was validated by quantitative RT-PCR using independent samples. Results shed light on molecular mechanisms underlying neuroprotection by DNP and point to possible targets for development of novel therapeutics for neurodegenerative disorders.


Assuntos
2,4-Dinitrofenol/farmacologia , AMP Cíclico/genética , Hipocampo/metabolismo , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/genética , Regulação para Cima/efeitos dos fármacos , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Hipocampo/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Int J Biochem Cell Biol ; 41(6): 1361-70, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19130896

RESUMO

Aggregates of the amyloid-beta peptide (Abeta) play a central role in the pathogenesis of Alzheimer's disease (AD). Identification of proteins that physiologically bind Abeta and modulate its aggregation and neurotoxicity could lead to the development of novel disease-modifying approaches in AD. By screening a phage display peptide library for high affinity ligands of aggregated Abeta(1-42), we isolated a peptide homologous to a highly conserved amino acid sequence present in the N-terminus of apolipoprotein A-I (apoA-I). We show that purified human apoA-I and Abeta form non-covalent complexes and that interaction with apoA-I affects the morphology of amyloid aggregates formed by Abeta. Significantly, Abeta/apoA-I complexes were also detected in cerebrospinal fluid from AD patients. Interestingly, apoA-I and apoA-I-containing reconstituted high density lipoprotein particles protect hippocampal neuronal cultures from Abeta-induced oxidative stress and neurodegeneration. These results suggest that human apoA-I modulates Abeta aggregation and Abeta-induced neuronal damage and that the Abeta-binding domain in apoA-I may constitute a novel framework for the design of inhibitors of Abeta toxicity.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Apolipoproteína A-I/metabolismo , Fragmentos de Peptídeos/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Sequência de Aminoácidos , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/toxicidade , Animais , Apolipoproteína A-I/genética , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/toxicidade , Gravidez , Ratos , Ratos Sprague-Dawley
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