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1.
J Neural Eng ; 21(2)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38579696

RESUMO

Objective.Artificial neural networks (ANNs) are state-of-the-art tools for modeling and decoding neural activity, but deploying them in closed-loop experiments with tight timing constraints is challenging due to their limited support in existing real-time frameworks. Researchers need a platform that fully supports high-level languages for running ANNs (e.g. Python and Julia) while maintaining support for languages that are critical for low-latency data acquisition and processing (e.g. C and C++).Approach.To address these needs, we introduce the Backend for Realtime Asynchronous Neural Decoding (BRAND). BRAND comprises Linux processes, termednodes, which communicate with each other in agraphvia streams of data. Its asynchronous design allows for acquisition, control, and analysis to be executed in parallel on streams of data that may operate at different timescales. BRAND uses Redis, an in-memory database, to send data between nodes, which enables fast inter-process communication and supports 54 different programming languages. Thus, developers can easily deploy existing ANN models in BRAND with minimal implementation changes.Main results.In our tests, BRAND achieved <600 microsecond latency between processes when sending large quantities of data (1024 channels of 30 kHz neural data in 1 ms chunks). BRAND runs a brain-computer interface with a recurrent neural network (RNN) decoder with less than 8 ms of latency from neural data input to decoder prediction. In a real-world demonstration of the system, participant T11 in the BrainGate2 clinical trial (ClinicalTrials.gov Identifier: NCT00912041) performed a standard cursor control task, in which 30 kHz signal processing, RNN decoding, task control, and graphics were all executed in BRAND. This system also supports real-time inference with complex latent variable models like Latent Factor Analysis via Dynamical Systems.Significance.By providing a framework that is fast, modular, and language-agnostic, BRAND lowers the barriers to integrating the latest tools in neuroscience and machine learning into closed-loop experiments.


Assuntos
Interfaces Cérebro-Computador , Neurociências , Humanos , Redes Neurais de Computação
2.
bioRxiv ; 2023 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-37609167

RESUMO

Artificial neural networks (ANNs) are state-of-the-art tools for modeling and decoding neural activity, but deploying them in closed-loop experiments with tight timing constraints is challenging due to their limited support in existing real-time frameworks. Researchers need a platform that fully supports high-level languages for running ANNs (e.g., Python and Julia) while maintaining support for languages that are critical for low-latency data acquisition and processing (e.g., C and C++). To address these needs, we introduce the Backend for Realtime Asynchronous Neural Decoding (BRAND). BRAND comprises Linux processes, termed nodes , which communicate with each other in a graph via streams of data. Its asynchronous design allows for acquisition, control, and analysis to be executed in parallel on streams of data that may operate at different timescales. BRAND uses Redis to send data between nodes, which enables fast inter-process communication and supports 54 different programming languages. Thus, developers can easily deploy existing ANN models in BRAND with minimal implementation changes. In our tests, BRAND achieved <600 microsecond latency between processes when sending large quantities of data (1024 channels of 30 kHz neural data in 1-millisecond chunks). BRAND runs a brain-computer interface with a recurrent neural network (RNN) decoder with less than 8 milliseconds of latency from neural data input to decoder prediction. In a real-world demonstration of the system, participant T11 in the BrainGate2 clinical trial performed a standard cursor control task, in which 30 kHz signal processing, RNN decoding, task control, and graphics were all executed in BRAND. This system also supports real-time inference with complex latent variable models like Latent Factor Analysis via Dynamical Systems. By providing a framework that is fast, modular, and language-agnostic, BRAND lowers the barriers to integrating the latest tools in neuroscience and machine learning into closed-loop experiments.

3.
Nature ; 568(7753): 466-467, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31019323

Assuntos
Idioma , Fala , Encéfalo
4.
Onderstepoort J Vet Res ; 82(1): E1-4, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26304168

RESUMO

Eight outbreaks of peste des petits ruminants in sheep and goats were reported in White Nile State, Sudan, between 2008 and 2009. A mortality rate of 4.2% was reported across the different outbreaks. Clinically the disease was characterised by high fever, ocular and nasal discharge, pneumonia, ulceration of the mucous membranes, diarrhoea and death. The postmortem findings included necrotic lesions in the mouth and gastrointestinal tract, and swollen, oedematous lymph nodes associated with the lungs and intestine. Of the 209 serum samples tested by competitive enzyme-linked immunosorbent assay, 113 (54%) were found positive. Peste des petits ruminants virus was confirmed in tissues, nasal swabs and blood samples by immunocapture enzyme-linked immunosorbent assay, reverse-transcription polymerase chain reaction and isolation of the virus in culture of lamb testicle cells.


Assuntos
Surtos de Doenças/veterinária , Doenças das Cabras/epidemiologia , Peste dos Pequenos Ruminantes/epidemiologia , Vírus da Peste dos Pequenos Ruminantes/isolamento & purificação , Doenças dos Ovinos/epidemiologia , Animais , Doenças das Cabras/mortalidade , Doenças das Cabras/virologia , Cabras , Peste dos Pequenos Ruminantes/mortalidade , Peste dos Pequenos Ruminantes/virologia , Ovinos , Doenças dos Ovinos/mortalidade , Doenças dos Ovinos/virologia , Sudão/epidemiologia
5.
Virol J ; 12: 124, 2015 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-26260127

RESUMO

BACKGROUND: Camel contagious ecthyma (CCE) is an important viral disease of camelids caused by a poxvirus of the genus parapoxvirus (PPV) of the family Poxviridae. The disease has been reported in west and east of the Sudan causing economical losses. However, the PPVs that cause the disease in camels of the Sudan have not yet subjected to genetic characterization. At present, the PPV that cause CCE cannot be properly classified because only few isolates that have been genetically analyzed. METHODS AND RESULTS: PCR was used to amplify the B2L gene of the PPV directly from clinical specimens collected from dromedary camels affected with contagious ecthyma in the Sudan between 1993 and 2013. PCR products were sequenced and subjected to genetic analysis. The results provided evidence for close relationships and genetic variation of the camel PPV (CPPV) represented by the circulation of both Pseudocowpox virus (PCPV) and Orf virus (ORFV) strains among dromedary camels in the Sudan. Based on the B2L gene sequence the available CPPV isolates can be divided into two genetic clades or lineages; the Asian lineage represented by isolates from Saudi Arabia, Bahrain and India and the African lineage comprising isolates from the Sudan. CONCLUSION: The camel parapoxvirus is genetically diverse involving predominantly viruses close to PCPV in addition to ORFVs, and can be divided into two genetically distant lineages. Based on sequences of the B2L gene it is not possible to suggest that the viruses that cause CCE form a monophylogenetic group or species within the PPV phylogeny.


Assuntos
Ectima Contagioso/virologia , Genes Virais , Parapoxvirus/classificação , Parapoxvirus/genética , Sequência de Aminoácidos , Animais , Composição de Bases , Camelus , Análise por Conglomerados , DNA Viral , Fases de Leitura Aberta
6.
Infect Genet Evol ; 21: 58-66, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24184096

RESUMO

Animal-human interspecies transmission is thought to play a significant role in influencing rotavirus strain diversity in humans. Proving this concept requires a better understanding of the complete genetic constellation of rotaviruses circulating in various animal species. However, very few whole genomes of animal rotaviruses, especially in developing countries, are available. In this study, complete genetic configuration of the first African camel rotavirus strain (RVA/Camel-wt/SDN/MRC-DPRU447/2002/G8P[11]) was assigned a unique G8-P[11]-I2-R2-C2-M2-A18-N2-T6-E2-H3 genotype constellation that has not been reported in other ruminants. It contained a novel NSP1 genotype (genotype A18). The evolutionary dynamics of the genome segments of strain MRC-DPRU447 were rather complex compared to those found in other camelids. Its genome segments 1, 3, 7-10 were closely related (>93% nucleotide identity) to those of human-animal reassortant strains like RVA/Human-tc/ITA/PA169/1988/G6P[14] and RVA/Human-wt/HUN/Hun5/1997/G6P[14], segments 4, 6 and 11 shared common ancestry (>95% nucleotide identity) with bovine rotaviruses like strains RVA/Cow-wt/CHN/DQ-75/2008/G10P[11] and RVA/Cow-wt/KOR/KJ19-2/XXXX/G6P[7], whereas segment 2 was closely related (94% nucleotide identity) to guanaco rotavirus strain RVA/Guanaco-wt/ARG/Rio_Negro/1998/G8P[1]. Its genetic backbone consisted of DS-1-like, AU-1-like, artiodactyl-like and a novel A18 genotype. This suggests that strain MRC-DPRU447 potentially emerged through multiple reassortment events between several mammalian rotaviruses of at least two genogroups or simply strain MRC-DPRU447 display a unique progenitor genotypes. Close relationship between some of the genome segments of strain MRC-DPRU447 to human rotaviruses suggests previous occurrence of reassortment processes combined with interspecies transmission between humans and camels. The whole genome data for strain MRC-DPRU447 adds to the much needed animal rotavirus data from Africa which is limited at the moment.


Assuntos
Camelus , Infecções por Rotavirus/veterinária , Rotavirus/classificação , Rotavirus/genética , África , Animais , Bovinos , Evolução Molecular , Genoma Viral , Genótipo , Humanos , Filogenia , Rotavirus/isolamento & purificação , Infecções por Rotavirus/virologia
7.
Acta Trop ; 116(2): 161-5, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20707980

RESUMO

In mid-August 2004, an outbreak of a previously unknown fatal disease of camels was reported to Kassala State veterinary authorities. Several areas in the state were visited during August-October 2004 to collect epidemiological data and specimens for diagnosis. Clinically the disease was characterized by sudden death of apparently healthy animals and yellowish and later bloody diarrhea and abortion. The disease outbreaks coincided with the seasonal movement of animals towards autumn green pasture. Death was always sudden and proceeded with colic and difficulty in respiration. Mortality rate ranged between 0% and 50% and vary in accordance with the area with a mean of 7.4%. More than 80% of deaths were in pregnant and recently-delivered she-camels. All age, sex and breed groups were affected but more than 50% of deaths were reported in adult animals in comparison to calves and young camels. The main post-mortem findings include lung congestion and consolidation, paleness and fragility of liver, enlarged lymph nodes and congestion and hemorrhage of small intestine and stomach. Agar gel diffusion test (AGDT), RT-PCR and virus isolation in cell culture gave positive results for peste des petits ruminants virus (PPRV), a virus belonging to the Morbillivirus, Genus, member of the family Paramyxoviridae. The effect of this new devastating disease on camel production in the affected area was discussed as well as proposals for future research.


Assuntos
Camelus/virologia , Surtos de Doenças/veterinária , Peste dos Pequenos Ruminantes/veterinária , Distribuição por Idade , Animais , Autopsia/veterinária , Feminino , Entrevistas como Assunto , Masculino , Peste dos Pequenos Ruminantes/epidemiologia , Peste dos Pequenos Ruminantes/patologia , Vírus da Peste dos Pequenos Ruminantes/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Sudão/epidemiologia
8.
Trop Anim Health Prod ; 42(6): 1203-7, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20376559

RESUMO

The role of pestivirus particularly bovine viral diarrhea virus (BVDV) in causing respiratory infections in camels was studied in four different localities in Sudan. The evaluation was carried out using ELISA, and positive specimens were further tested using direct fluorescent antibody technique (FAT) and reverse transcriptase polymerase chain reaction (RT-PCR) for confirmation. The overall detected seroprevalence of BVD in camel sera was 84.6% with the highest prevalence in Western Sudan (92.5%) and with most of positives showing 2+ and 3+ titer. Out of 186 lung specimens examined for BVDV antigen, 13 were found positive (7%) with the highest prevalence in Central Sudan. All ELISA-positive specimens were positive using FAT and RT-PCR. To our knowledge, this is the first report for the detection of BVDV antigen and antibodies in camels in Sudan.


Assuntos
Camelus/virologia , Vírus da Diarreia Viral Bovina , Surtos de Doenças/veterinária , Infecções por Pestivirus/epidemiologia , Infecções por Pestivirus/veterinária , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/veterinária , Animais , Primers do DNA/genética , Demografia , Ensaio de Imunoadsorção Enzimática , Imunofluorescência , Pulmão/virologia , Infecções Respiratórias/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estudos Soroepidemiológicos , Sudão/epidemiologia
9.
Trop Anim Health Prod ; 42(1): 89-93, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19548103

RESUMO

The current situation of PPR in Sudan was investigated. A total of 61 tissue samples were collected from various PPR suspected outbreaks in sheep in Sudan during 2008. Collected tissue samples were tested for PPR antigen using IcELISA, PPR antigen was detected in 26 out of 61 samples (42.6%). Highest antigen detection rate was in specimens collected from western Sudan. A total of 1198 serum samples were collected from sheep (n = 500), camels (n = 392), and goats (n = 306) from different areas in Sudan (Khartoum, Gezira, Tambool, River Nile, Kordofan, White Nile, Blue Nile, Gedarif, Kassala, Halfa ElGadida, Port Sudan). Collected sera were examined for PPR antibodies using cELISA, a total of 336 (67.2%) sheep, 170 (55.6%) goat and 1 (0.3%) camel samples were found to be positive.


Assuntos
Camelus/virologia , Surtos de Doenças/veterinária , Doenças das Cabras/virologia , Peste dos Pequenos Ruminantes/veterinária , Vírus da Peste dos Pequenos Ruminantes/isolamento & purificação , Doenças dos Ovinos/virologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/análise , Camelus/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Cabras/epidemiologia , Doenças das Cabras/imunologia , Cabras , Peste dos Pequenos Ruminantes/epidemiologia , Peste dos Pequenos Ruminantes/imunologia , Peste dos Pequenos Ruminantes/virologia , Vírus da Peste dos Pequenos Ruminantes/imunologia , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/imunologia , Sudão/epidemiologia
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