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1.
Heliyon ; 10(2): e24183, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38298679

RESUMO

Electric load forecasting is a vital task for energy management and policy-making. However, it is also a challenging problem due to the complex and dynamic nature of electric load data. In this paper, a novel technique, called LSV/MOPA, has been proposed for electric load forecasting. The technique is a hybrid model that combines the advantages of Long Short-Term Memory (LSTM) and Support Vector Regression (SVR), two powerful artificial intelligence algorithms. The hybrid model is further optimized by a newly Modified Orca Predation Algorithm (MOPA), which enhances the forecasting accuracy and efficiency. The LSV/MOPA model has been applied to historical electric load data from South Korea, covering four regions and 20 years. The LSV/MOPA model has been compared with other state-of-the-art forecasting techniques, including SVR/FFA, LSTM/BO, LSTM-SVR, and CNN-LSTM. The results show that the LSV/MOPA model with minimum average mean absolute percentage deviation error, including 365 in northern region, 12.8 in southern region, 8.6 in central region, and 30.8 in eastern region, provides the best fitting and outperforms the other techniques in terms of the Mean Absolute Percentage Deviation (MAPD) index, achieving lower values for all regions and years. The LSV/MOPA model also exhibits faster convergence and better generalization than the other techniques. This study demonstrates the effectiveness and superiority of the LSV/MOPA model for electric load forecasting and suggests its potential applications in other sectors where accurate forecasting is crucial.

2.
Heliyon ; 9(6): e16593, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37274681

RESUMO

Today, an important problem of the building energy performance area is carrying out multi-criteria optimizations of real building designs. To solve this problem, a new method based on a meta-model is proposed in this study. Hence, the EnergyPlus™ is used as the simulation tool for the performance simulation of the building, then a couple of the multi-criteria Modified Coot Optimization Algorithm (MCOA) dynamically combined with the artificial neural network meta-models (ANN-MM) are employed. For the sample generation applied for training and validation of ANN meta-models, an optimum way is presented by this method to minimize the whole building energy simulations needed for their training, and validate precise results of optimization. Moreover, the method is used for the thermal comfort and energy efficiency optimization of a real house to achieve the optimum balance between the heating and cooling behavior of the case building. 12 effective design variables of this case study are selected. Also, the achieved results are put in comparison with the "true" Pareto front found through an optimization method based on simulation performed for more validation. It is assumed that 1280 points are adequate in this case study to obtain precise results on the Pareto set. Thus, 75% of the required simulations' number based on physics has been saved by this size of sample considering the 5120 applied in the method based on simulation. Consequently, the optimum Pareto set of a real multi-criteria building efficiency optimization problem is achieved by the proposed method and accurate results are achieved.

3.
RSC Adv ; 9(28): 15966-15975, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35521369

RESUMO

An effective process for the green and rapid synthesis of biologically active polysubstituted pyrroles and 1,2,4,5-tetrasubstituted imidazoles derivatives using Cu@imine/Fe3O4 MNPs catalyst under solvent-free conditions is explained. This catalyst showed high reactivity for the synthesis of a set of different derivatives of polysubstituted pyrroles and 1,2,4,5-tetrasubstituted imidazole derivatives under appropriate reaction conditions and short times. Moreover, the catalyst was also recycled and reused for six runs with no considerable reduction in reactivity and yields. Compared to the reported procedures, this method consistently demonstrates the advantages of low catalyst loading, short reaction times, easy separation and purification of the products, high yields, and high recoverability and recoverability of the catalyst.

4.
Neuron ; 68(3): 428-41, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21040845

RESUMO

The entorhinal cortex (EC) is one of the earliest affected, most vulnerable brain regions in Alzheimer's disease (AD), which is associated with amyloid-ß (Aß) accumulation in many brain areas. Selective overexpression of mutant amyloid precursor protein (APP) predominantly in layer II/III neurons of the EC caused cognitive and behavioral abnormalities characteristic of mouse models with widespread neuronal APP overexpression, including hyperactivity, disinhibition, and spatial learning and memory deficits. APP/Aß overexpression in the EC elicited abnormalities in synaptic functions and activity-related molecules in the dentate gyrus and CA1 and epileptiform activity in parietal cortex. Soluble Aß was observed in the dentate gyrus, and Aß deposits in the hippocampus were localized to perforant pathway terminal fields. Thus, APP/Aß expression in EC neurons causes transsynaptic deficits that could initiate the cortical-hippocampal network dysfunction in mouse models and human patients with AD.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Córtex Entorrinal/patologia , Hipocampo/patologia , Rede Nervosa/patologia , Neurônios/efeitos dos fármacos , Sinapses/patologia , Doença de Alzheimer/psicologia , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/fisiologia , Animais , Comportamento Animal/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Transtornos Cognitivos/psicologia , Progressão da Doença , Eletroencefalografia , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Placa Amiloide/patologia
5.
Proc Natl Acad Sci U S A ; 107(42): 18173-8, 2010 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-20921410

RESUMO

Long-term memory relies on modulation of synaptic connections in response to experience. This plasticity involves trafficking of AMPA receptors (AMPAR) and alteration of spine morphology. Arc, a gene induced by synaptic activity, mediates the endocytosis of AMPA receptors and is required for both long-term and homeostatic plasticity. We found that Arc increases spine density and regulates spine morphology by increasing the proportion of thin spines. Furthermore, Arc specifically reduces surface GluR1 internalization at thin spines, and Arc mutants that fail to facilitate AMPAR endocytosis do not increase the proportion of thin spines, suggesting that Arc-mediated AMPAR endocytosis facilitates alterations in spine morphology. Thus, by linking spine morphology with AMPAR endocytosis, Arc balances synaptic downscaling with increased structural plasticity. Supporting this, loss of Arc in vivo leads to a significant decrease in the proportion of thin spines and an epileptic-like network hyperexcitability.


Assuntos
Proteínas do Citoesqueleto/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Sinapses/fisiologia , Animais , Proteínas do Citoesqueleto/genética , Memória , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Neuropeptídeo Y/metabolismo , Receptores de AMPA/metabolismo , Receptores de AMPA/fisiologia , Sinapses/metabolismo
6.
Nature ; 466(7306): 622-6, 2010 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-20613723

RESUMO

Neural circuits of the basal ganglia are critical for motor planning and action selection. Two parallel basal ganglia pathways have been described, and have been proposed to exert opposing influences on motor function. According to this classical model, activation of the 'direct' pathway facilitates movement and activation of the 'indirect' pathway inhibits movement. However, more recent anatomical and functional evidence has called into question the validity of this hypothesis. Because this model has never been empirically tested, the specific function of these circuits in behaving animals remains unknown. Here we report direct activation of basal ganglia circuitry in vivo, using optogenetic control of direct- and indirect-pathway medium spiny projection neurons (MSNs), achieved through Cre-dependent viral expression of channelrhodopsin-2 in the striatum of bacterial artificial chromosome transgenic mice expressing Cre recombinase under control of regulatory elements for the dopamine D1 or D2 receptor. Bilateral excitation of indirect-pathway MSNs elicited a parkinsonian state, distinguished by increased freezing, bradykinesia and decreased locomotor initiations. In contrast, activation of direct-pathway MSNs reduced freezing and increased locomotion. In a mouse model of Parkinson's disease, direct-pathway activation completely rescued deficits in freezing, bradykinesia and locomotor initiation. Taken together, our findings establish a critical role for basal ganglia circuitry in the bidirectional regulation of motor behaviour and indicate that modulation of direct-pathway circuitry may represent an effective therapeutic strategy for ameliorating parkinsonian motor deficits.


Assuntos
Gânglios da Base/citologia , Gânglios da Base/fisiopatologia , Modelos Neurológicos , Vias Neurais/fisiopatologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Animais , Gânglios da Base/patologia , Gânglios da Base/fisiologia , Channelrhodopsins , Cromossomos Artificiais Bacterianos/genética , Modelos Animais de Doenças , Marcha , Hipocinesia/complicações , Hipocinesia/genética , Hipocinesia/fisiopatologia , Integrases/genética , Integrases/metabolismo , Camundongos , Camundongos Transgênicos , Atividade Motora/fisiologia , Neostriado/citologia , Neostriado/patologia , Neostriado/fisiologia , Neostriado/fisiopatologia , Vias Neurais/citologia , Vias Neurais/patologia , Vias Neurais/fisiologia , Neurônios/citologia , Neurônios/patologia , Neurônios/fisiologia , Oxidopamina , Doença de Parkinson/complicações , Doença de Parkinson/genética , Desempenho Psicomotor , Receptores Dopaminérgicos/genética
7.
J Neurosci ; 30(6): 2223-34, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20147549

RESUMO

Striatal GABAergic microcircuits are critical for motor function, yet their properties remain enigmatic due to difficulties in targeting striatal interneurons for electrophysiological analysis. Here, we use Lhx6-GFP transgenic mice to identify GABAergic interneurons and investigate their regulation of striatal direct- and indirect-pathway medium spiny neurons (MSNs). We find that the two major interneuron populations, persistent low-threshold spiking (PLTS) and fast spiking (FS) interneurons, differ substantially in their excitatory inputs and inhibitory outputs. Excitatory synaptic currents recorded from PLTS interneurons are characterized by a small, nonrectifying AMPA receptor-mediated component and a NMDA receptor-mediated component. In contrast, glutamatergic synaptic currents in FS interneurons have a large, strongly rectifying AMPA receptor-mediated component, but no detectable NMDA receptor-mediated responses. Consistent with their axonal morphology, the output of individual PLTS interneurons is relatively weak and sparse, whereas FS interneurons are robustly connected to MSNs and other FS interneurons and appear to mediate the bulk of feedforward inhibition. Synaptic depression of FS outputs is relatively insensitive to firing frequency, and dynamic-clamp experiments reveal that these short-term dynamics enable feedforward inhibition to remain efficacious across a broad frequency range. Surprisingly, we find that FS interneurons preferentially target direct-pathway MSNs over indirect-pathway MSNs, suggesting a potential mechanism for rapid pathway-specific regulation of striatal output pathways.


Assuntos
Corpo Estriado/fisiologia , Interneurônios/fisiologia , Ácido gama-Aminobutírico/metabolismo , Potenciais de Ação , Animais , Camundongos , Camundongos Transgênicos , Inibição Neural , Vias Neurais , Técnicas de Patch-Clamp , Receptores de AMPA/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Sinapses/fisiologia
8.
Dev Biol ; 340(1): 41-53, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20096683

RESUMO

Precise control of neuronal migration is essential for proper function of the brain. Taking a forward genetic screen, we isolated a mutant mouse with defects in interneuron migration. By genetic mapping, we identified a frame shift mutation in the pericentrin (Pcnt) gene. The Pcnt gene encodes a large centrosomal coiled-coil protein that has been implicated in schizophrenia. Recently, frame shift and premature termination mutations in the pericentrin (PCNT) gene were identified in individuals with Seckel syndrome and microcephalic osteodysplastic primordial dwarfism (MOPD II), both of which are characterized by greatly reduced body and brain sizes. The mouse Pcnt mutant shares features with the human syndromes in its overall growth retardation and reduced brain size. We found that dorsal lateral ganglionic eminence (dLGE)-derived olfactory bulb interneurons are severely affected and distributed abnormally in the rostral forebrain in the mutant. Furthermore, mutant interneurons exhibit abnormal migration behavior and RNA interference knockdown of Pcnt impairs cell migration along the rostal migratory stream (RMS) into the olfactory bulb. These findings indicate that pericentrin is required for proper migration of olfactory bulb interneurons and provide a developmental basis for association of pericentrin function with interneuron defects in human schizophrenia.


Assuntos
Antígenos/genética , Movimento Celular/fisiologia , Interneurônios/citologia , Mutação , Bulbo Olfatório/metabolismo , Animais , Centrossomo/metabolismo , Interneurônios/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
J Neurosci ; 30(1): 372-81, 2010 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-20053918

RESUMO

Previous studies suggested that cleavage of the amyloid precursor protein (APP) at aspartate residue 664 by caspases may play a key role in the pathogenesis of Alzheimer's disease. Mutation of this site (D664A) prevents caspase cleavage and the generation of the C-terminal APP fragments C31 and Jcasp, which have been proposed to mediate amyloid-beta (Abeta) neurotoxicity. Here we compared human APP transgenic mice with (B254) and without (J20) the D664A mutation in a battery of tests. Before Abeta deposition, hAPP-B254 and hAPP-J20 mice had comparable hippocampal levels of Abeta(1-42). At 2-3 or 5-7 months of age, hAPP-B254 and hAPP-J20 mice had similar abnormalities relative to nontransgenic mice in spatial and nonspatial learning and memory, elevated plus maze performance, electrophysiological measures of synaptic transmission and plasticity, and levels of synaptic activity-related proteins. Thus, caspase cleavage of APP at position D664 and generation of C31 do not play a critical role in the development of these abnormalities.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Caspases/metabolismo , Modelos Animais de Doenças , Neurônios/metabolismo , Desempenho Psicomotor/fisiologia , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Humanos , Hidrólise , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Neurônios/patologia
10.
Neuron ; 55(5): 697-711, 2007 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-17785178

RESUMO

Neural network dysfunction may play an important role in Alzheimer's disease (AD). Neuronal circuits vulnerable to AD are also affected in human amyloid precursor protein (hAPP) transgenic mice. hAPP mice with high levels of amyloid-beta peptides in the brain develop AD-like abnormalities, including cognitive deficits and depletions of calcium-related proteins in the dentate gyrus, a region critically involved in learning and memory. Here, we report that hAPP mice have spontaneous nonconvulsive seizure activity in cortical and hippocampal networks, which is associated with GABAergic sprouting, enhanced synaptic inhibition, and synaptic plasticity deficits in the dentate gyrus. Many Abeta-induced neuronal alterations could be simulated in nontransgenic mice by excitotoxin challenge and prevented in hAPP mice by blocking overexcitation. Aberrant increases in network excitability and compensatory inhibitory mechanisms in the hippocampus may contribute to Abeta-induced neurological deficits in hAPP mice and, possibly, also in humans with AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Transtornos Cognitivos/fisiopatologia , Giro Denteado/fisiopatologia , Epilepsia/fisiopatologia , Inibição Neural/genética , Vias Neurais/fisiopatologia , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/metabolismo , Giro Denteado/metabolismo , Modelos Animais de Doenças , Epilepsia/etiologia , Epilepsia/metabolismo , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Neocórtex/metabolismo , Neocórtex/fisiopatologia , Vias Neurais/metabolismo , Plasticidade Neuronal/fisiologia , Neurotoxinas/farmacologia , Transmissão Sináptica/genética , Ácido gama-Aminobutírico/metabolismo
11.
J Neurosci ; 27(11): 2727-33, 2007 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-17360894

RESUMO

Reelin regulates nervous system development and modulates synaptic plasticity in the adult brain. Several findings suggest that alterations in Reelin signaling may contribute to neuronal dysfunction associated with Alzheimer's disease (AD). Cell surface receptors for Reelin, including integrins and very-low-density lipoprotein receptor/apolipoprotein E2 receptor, may be targets of amyloid-beta (Abeta) peptides presumed to play key roles in the pathogenesis of AD. Reelin also regulates the extent of tau phosphorylation. Finally, increased amounts of Reelin fragments have been found in CSF from AD patients, suggesting altered processing of Reelin. We therefore hypothesized that Reelin levels might be altered in the brains of human amyloid precursor protein (hAPP) transgenic mice, particularly in brain regions vulnerable to AD such as hippocampus and entorhinal cortex. Compared with nontransgenic controls, hAPP mice had significantly fewer Reelin-expressing pyramidal cells in the entorhinal cortex, the major population of glutamatergic neurons expressing Reelin in the brain. Western blot analysis of the hippocampus, which receives projections from the entorhinal cortex, revealed significant reductions in Reelin levels. In contrast, the number of Reelin-expressing GABAergic interneurons was not altered in either the entorhinal cortex or the hippocampus. Thus, neuronal expression of hAPP/Abeta is sufficient to reduce Reelin expression in a specific population of entorhinal cortical pyramidal neurons in vivo. Underscoring the relevance of these findings, we found qualitatively similar reductions of Reelin-expressing pyramidal neurons in the entorhinal cortex of AD brains. We conclude that alterations in Reelin processing or signaling may be involved in AD-related neuronal dysfunction.


Assuntos
Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Moléculas de Adesão Celular Neuronais/deficiência , Moléculas de Adesão Celular Neuronais/genética , Córtex Entorrinal/metabolismo , Proteínas da Matriz Extracelular/deficiência , Proteínas da Matriz Extracelular/genética , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Serina Endopeptidases/deficiência , Serina Endopeptidases/genética , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/biossíntese , Animais , Moléculas de Adesão Celular Neuronais/fisiologia , Córtex Entorrinal/patologia , Proteínas da Matriz Extracelular/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas do Tecido Nervoso/fisiologia , Neurônios/patologia , Processamento de Proteína Pós-Traducional/genética , Células Piramidais/metabolismo , Células Piramidais/patologia , Proteína Reelina , Serina Endopeptidases/fisiologia , Transdução de Sinais/genética
12.
Cereb Cortex ; 16 Suppl 1: i82-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16766712

RESUMO

Most gamma-aminobutyric acidergic interneurons in the neocortex and hippocampus are derived from subpallial progenitors in the medial ganglionic eminence and migrate tangentially to the pallium, where they differentiate into a diverse set of neuronal subtypes. Toward elucidating the mechanisms underlying the generation of interneuron diversity, we have studied in mice the expression patterns in differentiating and mature neocortical interneurons of 8 transcription factors, including 6 homeobox (Dlx1, Dlx2, Dlx5, Arx, Lhx6, Cux2), 1 basic helix-loop-helix, (NPAS1), and 1 bZIP (MafB). Their patterns of expression change during interneuron differentiation and show distinct distributions within interneuron subpopulations in adult neocortex. This study is a first step to define the combinatorial codes of transcription factors that participate in regulating the specification and function of cortical interneuron subtypes.


Assuntos
Envelhecimento/fisiologia , Padronização Corporal/fisiologia , Interneurônios/citologia , Interneurônios/fisiologia , Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Fatores de Transcrição/metabolismo , Envelhecimento/patologia , Animais , Agregação Celular , Diferenciação Celular , Movimento Celular , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Técnicas In Vitro , Camundongos , Camundongos Knockout , Neocórtex/embriologia , Rede Nervosa/citologia , Rede Nervosa/embriologia , Rede Nervosa/crescimento & desenvolvimento , Organogênese/fisiologia , Distribuição Tecidual
13.
Nat Neurosci ; 8(8): 1059-68, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16007083

RESUMO

Dlx homeodomain transcription factors are essential during embryonic development for the production of forebrain GABAergic interneurons. Here we show that Dlx1 is also required for regulating the functional longevity of cortical and hippocampal interneurons in the adult brain. We demonstrate preferential Dlx1 expression in a subset of cortical and hippocampal interneurons which, in postnatal Dlx1 mutants, show a time-dependent reduction in number. This reduction preferentially affects calretinin(+) (bipolar cells) and somatostatin(+) subtypes (for example, bitufted cells), whereas parvalbumin(+) subpopulations (basket cells and chandelier cells) seem to be unaffected. Cell transplantation analysis demonstrates that interneuron loss reflects cell-autonomous functions of Dlx1. The decrease in the number of interneurons was associated with a reduction of GABA-mediated inhibitory postsynaptic current in neocortex and hippocampus in vitro and cortical dysrhythmia in vivo. Dlx1 mutant mice show generalized electrographic seizures and histological evidence of seizure-induced reorganization, linking the Dlx1 mutation to delayed-onset epilepsy associated with interneuron loss.


Assuntos
Epilepsia/patologia , Epilepsia/fisiopatologia , Deleção de Genes , Proteínas de Homeodomínio/genética , Interneurônios/patologia , Inibição Neural , Envelhecimento/metabolismo , Animais , Apoptose , Comportamento Animal , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/fisiopatologia , Contagem de Células , Córtex Cerebral/fisiopatologia , Epilepsia/genética , Epilepsia/psicologia , Camundongos , Camundongos Knockout , Neurônios , Sinapses , Fatores de Transcrição , Ácido gama-Aminobutírico/metabolismo
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