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1.
J Med Syst ; 42(11): 206, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30238165

RESUMO

In recent days, intelligent biomedical sensors and wearable devices are changing the healthcare industry by providing various heterogeneous vital signs of patients to the hospitals, caregivers, and clinicals. This collective form of monitoring sensor devices forms a very short-range Wireless Body Area Network (WBAN) and plays a key role in the data gathering process. If any sensor node in the network detects abnormal values that should be transmitted promptly via wireless medium with less delay. A single medium allows one-way delivery of a data packet, and it may not be sufficient to satisfy the high volume of communication demand between the sensor nodes in the network. In the same way, the packet prioritization does not guarantee the packet will get there on time and sometime it may cause priority conflicts among the nodes. It is only mean that the flow of delivery service handles that critical data packet before handling other data packets. However, unexploited time slots and bandwidth wastage will occur due to inefficient backoff management and collisions. To minimize the aforementioned issues, various backoff procedures, adaptive slot allocation mechanisms, priority-based medium access control protocols have been developed but suffer limitations in the context of providing priority-based channel access with less backoff conflicts and dedicated allocation of time slots for critical nodes in all cases. Based on these deliberations, a more effective Traffic Priority-based Channel Access Technique (TP-CAT) is proposed using IEEE 802.15.6 in order to minimize the transmission delay of critical data packet and solve conflicts among other priority nodes during the backoff phases. Firstly, a Low Threshold Criticality-based Adaptive Time slot Allocation algorithm (LT-CATA) is presented to decrease the priority slot conflicts between the low threshold data traffic from the same and different type of user priority nodes. Secondly, a High Threshold Criticality-based Adaptive Time slot Allocation algorithm (HT-CATA) is developed to reduce the priority slot conflicts between the high threshold data traffic from the same and different types of user priority nodes. Additionally, a novel Random Overlapping Backoff value Avoidance (ROBA) technique is introduced to eliminate the overlapping issue during the selection of random backoff value among the sensor nodes. Since, the proposed technique greatly reduced the channel access delay and transmission delay of critical data packet as well as other types of priority data packet. The Simulation results are verified in the CASTALIA 3.2 framework using omnet++ network simulater to relatively evaluate the performance metrics of the TP-CAT technique with state-of-the-art protocols. From the analysis of the results, it is evident that the TP-CAT technique provides better performance in terms of delay, energy consumption, and throughput in healthcare monitoring environments.


Assuntos
Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Algoritmos , Redes de Comunicação de Computadores , Corpo Humano , Humanos
2.
J Med Syst ; 42(10): 196, 2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30215143

RESUMO

Internet of Things (IoT) provides the collection of devices in different applications in which Wireless Body Area Network (WBAN) is placed an crucial role. The WBAN is a wireless sensor network consisting of sensor nodes that is collected from IoT which is implanted in the human body to remotely monitor the patient's physiological signals without affecting their routine work. During emergency situations or life-threatening situations there is a need for a better performance to deliver the actual data with an efficient transmission and there is still a challenge in efficient remote monitoring. So, in this paper an application for cross layer protocol design architecture of Elliptic Curve Digital Signature Algorithm (ECDSA) has been proposed. It replaces the protocol architecture of WBAN (IEEE 802.15.6), WMAN (IEEE 802.16), and 3G, WLAN (IEEE 802.11) or wired networks. The lightweight secure system provides secure data transmission and access control mechanisms by using ECDA-based proxy signature algorithm. The efficiency of the system is implemented using simulation models that were developed using NS-2, and the results obtained shows an optimum solution in terms of delay, PDR, throughput, jitter, packet transmission time, dropping ratio and packet delivery. The viability of the methodology proposed is illustrated by the response.


Assuntos
Privacidade , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Redes de Comunicação de Computadores , Corpo Humano , Humanos , Internet
3.
Radiat Res ; 183(1): 1-26, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25564719

RESUMO

During space travel astronauts are exposed to a variety of radiations, including galactic cosmic rays composed of high-energy protons and high-energy charged (HZE) nuclei, and solar particle events containing low- to medium-energy protons. Risks from these exposures include carcinogenesis, central nervous system damage and degenerative tissue effects. Currently, career radiation limits are based on estimates of fatal cancer risks calculated using a model that incorporates human epidemiological data from exposed populations, estimates of relative biological effectiveness and dose-response data from relevant mammalian experimental models. A major goal of space radiation risk assessment is to link mechanistic data from biological studies at NASA Space Radiation Laboratory and other particle accelerators with risk models. Early phenotypes of HZE exposure, such as the induction of reactive oxygen species, DNA damage signaling and inflammation, are sensitive to HZE damage complexity. This review summarizes our current understanding of critical areas within the DNA damage and oxidative stress arena and provides insight into their mechanistic interdependence and their usefulness in accurately modeling cancer and other risks in astronauts exposed to space radiation. Our ultimate goals are to examine potential links and crosstalk between early response modules activated by charged particle exposure, to identify critical areas that require further research and to use these data to reduced uncertainties in modeling cancer risk for astronauts. A clearer understanding of the links between early mechanistic aspects of high-LET response and later surrogate cancer end points could reveal key nodes that can be therapeutically targeted to mitigate the health effects from charged particle exposures.


Assuntos
Carcinogênese , Radiação Cósmica/efeitos adversos , Dano ao DNA , Reparo do DNA/efeitos da radiação , Exposição Ambiental/efeitos adversos , Neoplasias Induzidas por Radiação/patologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/efeitos da radiação , Humanos , Inflamação/etiologia , Inflamação/genética , Inflamação/metabolismo , Neoplasias Induzidas por Radiação/etiologia , Neoplasias Induzidas por Radiação/genética , Neoplasias Induzidas por Radiação/metabolismo
4.
Bioelectrochemistry ; 82(2): 135-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21784716

RESUMO

Marine and freshwater biofilm usually shift the open circuit potential (OCP) of stainless steel towards the electropositive direction by +450 mV vs SCE. The nature of oxide film and bacterial metabolism were also correlated with ennoblement process by various investigators. Glassy carbon electrode (GCE) was used in the present study and a shifting of potential in the positive side (+450 mV) was noticed. It indicates that biofilm contributes to the ennoblement process without any n/p-type semiconducting oxide film. The nature of the cathodic curve for the biofilm covered GCE is compared with the previous literature on the electrochemical behavior of stainless steel. The present study explains the oxidation and reduction peaks of biofilm covered GCE by cyclic voltammetry. Electrochemical impedance result reveals the diffusion process within the manganese biofilm. The present study confirms the previous investigations that the manganese biofilm rules the electrochemical behavior of materials and suggests that oxide film is not necessary to assist the ennoblement process.


Assuntos
Fenômenos Fisiológicos Bacterianos , Biofilmes , Carbono/química , Técnicas Eletroquímicas/instrumentação , Vidro/química , Compostos de Manganês/metabolismo , Óxidos/metabolismo , Eletrodos , Desenho de Equipamento , Oxirredução
5.
Opt Express ; 19(6): 5398-409, 2011 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-21445179

RESUMO

We investigate strong coupling between a single quantum dot (QD) and photonic crystal cavity through transmission modification of an evanescently coupled waveguide. Strong coupling is observed through modification of both the cavity scattering spectrum and waveguide transmission. We achieve an overall Q of 5800 and an exciton-photon coupling strength of 21 GHz for this integrated cavity-waveguide structure. The transmission contrast for the bare cavity mode is measured to be 24%. These results represent important progress towards integrated cavity quantum electrodynamics using a planar photonic architecture.

6.
Int J Neural Syst ; 16(2): 111-24, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16688851

RESUMO

We present a computational model of basal ganglia as a key player in exploratory behavior. The model describes exploration of a virtual rat in a simulated water pool experiment. The virtual rat is trained using a reward-based or reinforcement learning paradigm which requires units with stochastic behavior for exploration of the system's state space. We model the Subthalamic Nucleus-Globus Pallidus externa (STN-GPe) segment of the basal ganglia as a pair of neuronal layers with oscillatory dynamics, exhibiting a variety of dynamic regimes such as chaos, traveling waves and clustering. Invoking the property of chaotic systems to explore state-space, we suggest that the complex exploratory dynamics of STN-GPe system in conjunction with dopamine-based reward signaling from the Substantia Nigra pars compacta (SNc) present the two key ingredients of a reinforcement learning system.


Assuntos
Gânglios da Base/fisiologia , Simulação por Computador , Comportamento Exploratório/fisiologia , Modelos Neurológicos , Animais , Condicionamento Psicológico , Dopamina/fisiologia , Dinâmica não Linear , Ratos , Reforço Psicológico , Recompensa , Processos Estocásticos , Interface Usuário-Computador
7.
Indian J Med Microbiol ; 21(2): 133-4, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-17643000

RESUMO

Injection abscess is an iatrogenic infection occurring as an isolated case or as cluster outbreak. These infections occur due to contaminated injectables or lapse in sterilisation protocol. While pathogens such as Pseudomonas, Klebsiella, E. coli, and S. aureus are the usual causative agents, unusual organisms such as mycobacteria, particularly the rapidly growing non-tuberculous mycobacteria (NTM) may cause the abscess. The chances of overlooking these organisms is high unless an acid fast bacilli (AFB) smear and culture is done on all aspirated pus specimens. We report a case of a three year old child who presented with a gluteal abscess following an intramuscular infection with an unknown preparation.

8.
Indian J Med Sci ; 56(10): 489-94, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12712759

RESUMO

This study sought to determine whether dip stick strip test containing antibody for Plasmodium falciparum histidine rich protein-II (PfHRP-II) antigen could be used for identification of P. falciparum and P. vivax malaria in man. The results obtained were also compared with the results of standard microscopic examination. A total of 150 cases were included for the study. Fifty cases were non-febrile cases with no history of malaria acting as control group and the rest 100 cases were having fever and formed the test group. All the cases in the control group was found to be negative for both microscopic examination and strip test. In the test group, all samples that showed positive for P. falciparum by microscopy was also found to be positive for strip test. Whereas, all those samples that were positive for P. vivax in microscopic examination was found to be negative for strip test indicating species specificity of the strip test. In addition, two other cases that were negative for microscopic examination were found to be positive for the strip test. Statistical analysis was done to compare the validity of the results of strip test with that of the results of microscopic examination.


Assuntos
Malária Falciparum/diagnóstico , Proteínas de Protozoários/sangue , Fitas Reagentes , Estudos de Avaliação como Assunto , Humanos , Índia , Malária Falciparum/sangue , Malária Falciparum/patologia , Sensibilidade e Especificidade , Especificidade da Espécie
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