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1.
Artigo | IMSEAR | ID: sea-219462

RESUMO

This study evaluated the influence of organic fertilizers produced from spent lubricating oil (SLO) spiked aerobic composting technique on hydrocarbon degradation rate in soils. The compost windrows (Ft2 and Ft4), consisting of kitchen and agricultural wastes, were spiked with varying concentrations (2% and 4%) of SLO. The resultant organic fertilizers were employed as amendment in pollution simulated potted soils laid out in a complete randomized block design with three replications for 90 days. Results revealed higher counts of hydrocarbon utilizing microbes (HUB: 4.2±0.02×104cfu/g in Ft2, 3.0±0.02×104cfu/g in Ft4; HUF: 3.9±0.2×104cfu/g in Ft2, 2.5±0.02×104cfu/g in Ft4) in spiked compost compared to the control, Ft0 (HUB: 7.9±0.02×103cfu/g; HUF: 6.0±0.2×103cfu/g). Mean count in amended soils reflected a dose-dependent increase which followed the trend: Ft2 ? Ft0 ? Ft4 for the 5% (3.7×108 cfu/g), 10% (9.2×107 cfu/g) and 15% (6.9×107 cfu/g) levels of fertilizer treatments respectively. There was a significant (P<0.05) reduction in the TPH content of soils after 90days treatment with organic fertilizers. Generally, remediation efficiency followed the order: Ft2 ? Ft0 ? Ft4, with the highest (11.51%) achieved at 5% Ft2 application. Spiking technique was responsible for the higher counts of hydrocarbon utilizing microbes and enhanced bioremediation associated with the use of fertilizers Ft2.

2.
Journal of Biomedical Engineering ; (6): 692-699, 2023.
Artigo em Chinês | WPRIM | ID: wpr-1008889

RESUMO

With inherent sparse spike-based coding and asynchronous event-driven computation, spiking neural network (SNN) is naturally suitable for processing event stream data of event cameras. In order to improve the feature extraction and classification performance of bio-inspired hierarchical SNNs, in this paper an event camera object recognition system based on biological synaptic plasticity is proposed. In our system input event streams were firstly segmented adaptively using spiking neuron potential to improve computational efficiency of the system. Multi-layer feature learning and classification are implemented by our bio-inspired hierarchical SNN with synaptic plasticity. After Gabor filter-based event-driven convolution layer which extracted primary visual features of event streams, we used a feature learning layer with unsupervised spiking timing dependent plasticity (STDP) rule to help the network extract frequent salient features, and a feature learning layer with reward-modulated STDP rule to help the network learn diagnostic features. The classification accuracies of the network proposed in this paper on the four benchmark event stream datasets were better than the existing bio-inspired hierarchical SNNs. Moreover, our method showed good classification ability for short event stream input data, and was robust to input event stream noise. The results show that our method can improve the feature extraction and classification performance of this kind of SNNs for event camera object recognition.


Assuntos
Percepção Visual , Aprendizagem , Potenciais de Ação , Redes Neurais de Computação , Plasticidade Neuronal
3.
Journal of Biomedical Engineering ; (6): 986-994, 2021.
Artigo em Chinês | WPRIM | ID: wpr-921837

RESUMO

Under the current situation of the rapid development of brain-like artificial intelligence and the increasingly complex electromagnetic environment, the most bionic and anti-interference spiking neural network has shown great potential in computing speed, real-time information processing, and spatiotemporal data processing. Spiking neural network is the core part of brain-like artificial intelligence, which realizes brain-like computing by simulating the structure of biological neural network and the way of information transmission. This article first summarizes the advantages and disadvantages of the five models, and analyzes the characteristics of several network topologies. Then, it summarizes the spiking neural network algorithms. The unsupervised learning based on spike timing dependent plasticity (STDP) rules and four types of supervised learning algorithms are analyzed. Finally, the research on brain-like neuromorphic chips at home and abroad are reviewed. This paper aims to provide learning ideas and research directions for new colleagues in the field of spiking neural network.


Assuntos
Algoritmos , Inteligência Artificial , Encéfalo , Redes Neurais de Computação
4.
Artigo | IMSEAR | ID: sea-194435

RESUMO

Adult onset still’s disease is a rare systemic inflammatory disorder of unknown aetiology, characterized by clinical triad (high spiking fever, evanescent rash and arthritis) and biological triad with lack of serological markers as a true gold standard makes diagnosis difficulty. Here is a case of 32year old male presented with high grade fever for 2 months, joint pains and swelling for 1month rash for 3 days. O/E: pallor and B/L tender, swollen ankle and knee joints, and P/A: splenomegaly. Investigations showed-Hb%. 8 gms, neutrophilic leucocytosis with thrombocytosis, ESR:72 mm/1h, CRP elevated. ASO-titre, RA factor and Anti CCP antibodies are negative. Adult onset still’s disease is a heterogenous and rare systemic inflammatory disorder of unknown aetiology with lack of serological diagnostic modalities.

5.
Journal of Biomedical Engineering ; (6): 902-910, 2019.
Artigo em Chinês | WPRIM | ID: wpr-781848

RESUMO

Biological neural networks have dual properties of small-world attributes and scale-free attributes. Most of the current researches on neural networks are based on small-world networks or scale-free networks with lower clustering coefficient, however, the real brain network is a scale-free network with small-world attributes. In this paper, a scale-free spiking neural network with high clustering coefficient and small-world attribute was constructed. The dynamic evolution process was analyzed from three aspects: synaptic regulation process, firing characteristics and complex network characteristics. The experimental results show that, as time goes by, the synaptic strength gradually decreases and tends to be stable. As a result, the connection strength of the network decreases and tends to be stable; the firing rate of neurons gradually decreases and tends to be stable, and the synchronization becomes worse; the local information transmission efficiency is stable, the global information transmission efficiency is reduced and tends to be stable, and the small-world attributes are relatively stable. The dynamic characteristics vary with time and interact with each other. The regulation of synapses is based on the firing time of neurons, and the regulation of synapses will affect the firing of neurons and complex characteristics of networks. In this paper, a scale-free spiking neural network was constructed, which has biological authenticity. It lays a foundation for the research of artificial neural network and its engineering application.


Assuntos
Potenciais de Ação , Modelos Neurológicos , Redes Neurais de Computação , Plasticidade Neuronal , Sinapses
6.
Journal of Biomedical Engineering ; (6): 475-480, 2018.
Artigo em Chinês | WPRIM | ID: wpr-687606

RESUMO

The rapid development of artificial intelligence put forward higher requirements for the computational speed, resource consumption and the biological interpretation of computational neuroscience. Spiking neuron networks can carry a large amount of information, and realize the imitation of brain information processing. However, its hardware is an important way to realize its powerful computing ability, and it is also a challenging technical problem. The memristor currently is the electronic devices that functions closest to the neuron synapse, and able to respond to spike voltage in a highly similar spike timing dependent plasticity (STDP) mechanism with a biological brain, and has become a research hotspot to construct spiking neuron networks hardware circuit in recent years. Through consulting the relevant literature at home and abroad, this paper has made a thorough understanding and introduction to the research work of the spiking neuron networks based on the memristor in recent years.

7.
Res. Biomed. Eng. (Online) ; 33(4): 331-343, Oct.-Dec. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-896193

RESUMO

AbstractIntroduction: Since it was introduced in 2012, the Neuroid has been used to aid in understanding how functionally different neural populations contribute to sensory information processing. However, insights about whether this neuron-model could perform better than others or about when its utilization should be considered have not been provided yet. Methods In an attempt to address this issue, a comparison between the Neuroid and the leaky-integrate-and-fire (LIF) model in terms of accuracy and computational cost was performed. Both models were tested for different stimulation amplitudes and stimulation periods, with time step sizes ranging from 10-4 to 1 ms. Results It was found that, although the Neuroid was able to produce more accurate results than its original version, its accuracy was lower than the achieved with the LIF model solved by the forward Euler method. On the other hand, the Neuroid performed its calculations in an amount of time significantly lower (Mulfactorial ANOVA test, p < 0.05) than that required by the LIF model when it was solved by using the forward Euler method. Moreover, it was possible to use Neuroid-based networks to replicate biologically relevant firing patterns produced by low-scale networks composed of more detailed neuron-models. Conclusion Results suggest that the Neuroid could be an interesting choice when computational resources are limited, although its use might be restricted to a narrow band of applications.

8.
Braz. j. microbiol ; 45(2): 667-676, Apr.-June 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-723111

RESUMO

Salmonella enterica and Shigella species are commonly associated with food and water borne infections leading to gastrointestinal diseases. The present work was undertaken to develop a sensitive and reliable PCR based detection system for simultaneous detection of Salmonella enterica and Shigella at species level. For this the conserved regions of specific genes namely ipaH1, ipaH, wbgZ, wzy and invA were targeted for detection of Shigella genus, S. flexneri, S. sonnei, S. boydii and Salmonella enterica respectively along with an internal amplification control (IAC). The results showed that twenty Salmonella and eleven Shigella spp., were accurately identified by the assay without showing non-specificity against closely related other Enterobacteriaceae organisms and also against other pathogens. Further evaluation of multiplex PCR was undertaken on 50 natural samples of chicken, eggs and poultry litter and results compared with conventional culture isolation and identification procedure. The multiplex PCR identified the presence of Salmonella and Shigella strains with a short pre-enrichment step of 5 h in peptone water and the same samples were processed by conventional procedures for comparison. Therefore, this reported multiplex PCR can serve as an alternative to the tedious time-consuming procedure of culture and identification in food safety laboratories.


Assuntos
Animais , Humanos , Técnicas Bacteriológicas/métodos , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Salmonella enterica/isolamento & purificação , Shigella/isolamento & purificação , Galinhas , Microbiologia Ambiental , Microbiologia de Alimentos , Sensibilidade e Especificidade , Salmonelose Animal/microbiologia , Infecções por Salmonella/microbiologia
9.
Artigo em Inglês | IMSEAR | ID: sea-149463

RESUMO

Background & objectives: Bacillus anthracis, Yersinia pestis, Burkholderia pseudomallei and Brucella species are potential biowarfare agents. Classical bacteriological methods for their identification are cumbersome, time consuming and of potential risk to the handler. Methods: We describe a sensitive and specific multiplex polymerase chain reaction (mPCR) assay involving novel primers sets for the simultaneous detection of B. anthracis, Y. pestis, B. pseudomallei and Brucella species. An additional non-competitive internal amplification control (IAC) was also included. Results: The mPCR was found to be specific when tested against closely related organisms. The sensitivity of the assay in spiked blood samples was 50 colony forming units (cfus)/25 μl reaction, for the detection of B. anthracis, Y. pestis and Brucella species; and 150 cfus/25 μl reaction, for B. pseudomallei. The assay proved useful in correctly and promptly identifing the clinical isolates of the targeted agents recovered from patients, compared to the gold standard culture methods. Interpretation & conclusion: The assay described in this study showed promise to be useful in application as a routine detection cum diagnostic method for these pathogens.

10.
J Biosci ; 2011 Jun; 36(2): 309-328
Artigo em Inglês | IMSEAR | ID: sea-161552

RESUMO

The nucleus accumbens (NAc), a critical structure of the brain reward circuit, is implicated in normal goal-directed behaviour and learning as well as pathological conditions like schizophrenia and addiction. Its major cellular substrates, the medium spiny (MS) neurons, possess a wide variety of dendritic active conductances that may modulate the excitatory post synaptic potentials (EPSPs) and cell excitability. We examine this issue using a biophysically detailed 189-compartment stylized model of the NAc MS neuron, incorporating all the known active conductances. We find that, of all the active channels, inward rectifying K+ (KIR) channels play the primary role in modulating the resting membrane potential (RMP) and EPSPs in the down-state of the neuron. Reduction in the conductance of KIR channels evokes facilitatory effects on EPSPs accompanied by rises in local input resistance and membrane time constant. At depolarized membrane potentials closer to up-state levels, the slowly inactivating A-type potassium channel (KAs) conductance also plays a strong role in determining synaptic potential parameters and cell excitability. We discuss the implications of our results for the regulation of accumbal MS neuron biophysics and synaptic integration by intrinsic factors and extrinsic agents such as dopamine.

11.
Braz. j. microbiol ; 42(1): 181-186, Jan.-Mar. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-571388

RESUMO

In the present study, the efficacy of polymerase chain reaction (PCR) based on mapA gene of C. jejuni was tested for detection of Campylobacter jejuni in naturally infected as well as spiked faecal and food samples of human and animal origin. Simultaneously, all the samples were subjected to the cultural isolation of organism and biochemical characterization. The positive samples resulted in the amplification of a DNA fragment of size ~589 bp in PCR assay whereas the absence of such amplicon in DNA extracted from E. coli, Listeria, Salmonella and Staphylococcus confirmed the specificity of the primers. Of randomly collected 143 faecal samples comprising human diarrheic stools (43), cattle diarrheic faeces (48) and poultry faecal swabs (52) only 4, 3 and 8, respectively, could be detected by isolation whereas 6, 3 and 10, respectively, were found positive by PCR. However, among food samples viz. beef (30), milk (35), cheese (30), only one beef sample was detected both by culture as well as PCR. Additionally, PCR was found to be more sensitive for C. jejuni detection in spiked faecal and food samples (96.1 percent each) as relative to culture isolation which could detect the organism in 86.7 percent and 80 percent samples, respectively. The results depicted the superior efficacy of PCR for rapid screening of samples owing to its high sensitivity, specificity and automation potential.


Assuntos
Humanos , Animais , Infecções por Campylobacter , Campylobacter jejuni/genética , Campylobacter jejuni/isolamento & purificação , Eficácia , Infecções por Enterobacteriaceae , Fezes , Amplificação de Genes , Técnicas In Vitro , Reação em Cadeia da Polimerase/métodos , Fenômenos Químicos , Métodos , Métodos
12.
International Journal of Biomedical Engineering ; (6): 86-90, 2011.
Artigo em Chinês | WPRIM | ID: wpr-417227

RESUMO

Objective To analyse the variability of spontaneous firing frequencies and firing patterns of a Hippocampal CA1 neuron with the changes of extracellular potassium concentration[K+]0 and ion channel conductance.Methods A 16-compartment cable model of a Hippocampal CA1 neuron was developed based on the Warman model with computer software MATLAB.The dendrites contained no active channels,while five active channels (INa,INap,IDR,IA,IM)were contained in soma.In the model,the calcium currents and potassium currents(ICm,,ICT and IAHP) regulated by calcium concentration were not included.ResultsSimulation results showed that the neuron could generate periodicspontaneous firing activity.The spiking frequency increased with the increasing of[K+]0 and sodium conductance and decreasing of potassium conductance.Spontaneous single neuron activity appeared in singlet or in grouped bursts of two or three spikes.Conclusion The variability of spontaneous firing frequencies and firing patterns of single neuron are relevant to[K+]0 and ion channel conductance.

13.
Korean Journal of Clinical Microbiology ; : 150-153, 2007.
Artigo em Coreano | WPRIM | ID: wpr-110608

RESUMO

BACKGROUND: Colonial morphology of Candida albicans known as 'spiking' on a primary isolation blood agar plate (BAP) allows rapid and presumptive identification of C. albicans. We evaluated the 'spiking' appearance to identify C. albicans. METHODS: A total of 144 fully identified clinical isolates of yeasts and 10 type strains of yeasts were tested. All isolates obtained from the 5% CO2 incubation on BAP and chocolate agar plate (CHOC) were macroscopically examined for the presence of an irregular margin (spiking). The germ tube test was performed by incubating test organisms in 0.5 mL of pooled human sera. RESULTS: The sensitivity for BAP-spiking, CHOC-spiking and germ tube test were 93.7%, 91.1%, and 98.7%, respectively. The specificity for three methods was 100%. CONCLUSION: Use of the spiking identification on BAP can be useful for the economic and rapid presumptive identification of C. albicans in routine laboratories.


Assuntos
Humanos , Ágar , Cacau , Candida albicans , Candida , Sensibilidade e Especificidade , Leveduras
14.
Tuberculosis and Respiratory Diseases ; : 299-302, 1994.
Artigo em Coreano | WPRIM | ID: wpr-226827

RESUMO

A 33-year old male was admitted due to continuous high spiking fever for 2 months via local clinic. He had been diagnosed pulmonary tuberculosis at local clinic. However, spiking fever had not been controlled by anti-tuberculous medications. Chest PA showed confluent consolidation on right upper & mid-lung field. 5 anti-tuberculous regimens (Streptomycin, Isoniazid, Rifampin, Ethambutol, Pyrazinamaide) were administered initially and steroid therapy was followed for relieving toxic symptoms Very slowly resolved chest X-ray lesion and continuous fever suggested the possibility of misdiagnosis. After 60th hospital day, the chest X-ray lesion was resolved gradually and fever subsided almost completely. He was discharged on 76th hospital day with anti-tuberculous drugs and steroid(prednisolon), without any other problems except sustained mild fever.


Assuntos
Humanos , Masculino , Erros de Diagnóstico , Etambutol , Febre , Isoniazida , Pneumonia , Rifampina , Tórax , Tuberculose Pulmonar
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