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1.
QJM ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38851872

RESUMO

This review outlines diverse strategies for neutralizing bacterial toxins which are a significant threat to human health. Effective toxin neutralization is crucial in preventing and treating bacterial infections, especially those caused by antibiotic-resistant strains. Promising approaches include using monoclonal antibodies that target toxins and combining them with agents that directly target bacteria. Aptamers, synthetic molecules that bind to specific targets, provide a rapid and tailored method for inhibiting toxin activity and detecting pathogens. Cell membrane-coated nanoparticles mimic host cells and effectively neutralize toxins by diverting them and stimulating immune responses. These advancements have the potential to combat bacterial infections and alleviate the associated public health burden.

2.
Work ; 79(1): 267-275, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517832

RESUMO

BACKGROUND: Vibration is one of the harmful factors for forklift drivers. The use of non- standard seats and not paying attention to how the seats are maintained can be affected by the amount of vibration transmitted to the person. OBJECTIVE: This study investigates the amount of vibration transmitted from the forklift and the effect of different types of polyurethane foam in reducing the vibration transmitted from the forklift seat. METHODS: This descriptive-analytical study was performed on 38 forklifts in 4 diesel models with the same weight class. The amount of vibration transmitted from forklift seats according to ISO2631 standard, taking into account the effect of various factors such as foam type (hot and cold), thickness (6-12 cm), load and year Function was measured. The amount of vibration caused by the forklift on the seat and under the seat was evaluated using ISO7096 standard. RESULTS: The average total vibration of the whole body in all foams in no-load mode is more than with load. The transmission vibration of cold polyurethane foam is less than that of hot polyurethane foam. With increasing thickness, the efficiency of cold polyurethane foam increases by 12 cm and in the loaded state 40.63% and in the unloaded state 49.58% in reducing the vibration transmitted to drivers. CONCLUSION: The results of this study show that cold foam has better effectiveness and efficiency than hot polyurethane foam. Also, the thicker the foam, the less vibration is transmitted to the driver.


Assuntos
Poliuretanos , Vibração , Vibração/efeitos adversos , Humanos , Desenho de Equipamento/normas , Desenho de Equipamento/métodos , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/efeitos adversos , Veículos Automotores , Ergonomia/métodos
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2580-2583, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891781

RESUMO

Analyzing human gait from plantar pressure is critical for human health. The majority of works focus on classifying the healthy plantar pattern from unhealthy ones. Different from previous works, we adopt a generative adversarial network to produce healthy plantar pressure image for individual patients. In this work, we do not have pairs of images for training thus we cast the problem as an unsupervised generative adversarial learning task. Our network benefits from multiple components: an encoder-decoder generator, a convolution-based discriminator, a convolution-based evaluation network, and a new term in the loss function to preserve the person's gait style. Our method achieves high performance (99.8%) on the CAD WALK databases which have patients with hallux valgus disease.


Assuntos
Processamento de Imagem Assistida por Computador , Humanos
4.
Health Promot Perspect ; 8(4): 268-274, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30479980

RESUMO

Background: The purpose of this study was to assess the contrast perception of obstacles in a tunnel entrance which was placed in Ilam Province, Iran. Methods: An obstacle with the reflection coefficient of 20% was mounted at the entrance of thetunnel and then, the car was placed near the tunnel entrance and the intrinsic luminance of the road (Lr,intrinsic) and obstacle (Lo,intrinsic) were measured inside the car using the luminance meter. Results: Intrinsic luminance of obstacle and road at the entrance of the tunnel were measured as 41 and 17 cd/m2, respectively. The contrast perception of obstacle in deriver's eyes and in the safe stopping distance (SSD) from the tunnel entrance was determined as 2.79 cd/m2. At the entrance of the studied tunnel, the contrast perception of obstacles with the reflection coefficient of 20% was lower than the minimum contrast perception (28%) recommended by International Commission on Illumination. Conclusion: The main conclusion that can be drawn from it, is that this obstacle in the SSD from the tunnel entrance cannot be conceived by the drivers, which may lead to higher rate of road traffic crashes.

5.
Microelectron Eng ; 195: 50-56, 2018 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-30270957

RESUMO

Heterogeneous substrates with moderate and extreme wettability contrasts were fabricated by comprising of superhydrophobic/hydrophilic and superhydrophobic/extremely hydrophilic surfaces, respectively. The interactions of water droplets impinging on the surfaces with sharp wettability contrasts were investigated experimentally. The impinging droplets that slightly touch the hydrophilic or extremely hydrophilic areas on each substrate exhibit a directional rebounding towards the more wetting surfaces, i.e., hydrophilic or extremely hydrophilic surface. The trajectory and landing distance of the rebounded droplets were tailored by controlling the releasing height of the droplet, wetting contrast across the border, and portion of the droplet touching the more wetting surface of the substrates with wettability contrasts. The landing distance of the droplet increases with the increased releasing height and higher wettability contrast across the border. Increasing the portion of the impinging droplet touching the more wetting surface of the heterogeneous substrates leads to the shorter landing distance of rebounded droplets.

6.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 3194-3197, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29060577

RESUMO

Multiple-Choice Decision-Making Tasks are widely used to analyze behavior and infer underlying cognitive states that shape the decision and learning processes. The behavioral signals recorded in these tasks are dynamic and often non-Gaussian - for instance, when learning a multiple choice association task. Previously developed estimation algorithms for latent behavioral variables do not address multiple-choice responses. In this research, we use a state-space modeling framework to predict a cognitive learning state related to multiple choice decisions, which are best described by a multinomial distribution. The proposed algorithm combines a multinomial filter/smoother and a variational Bayes technique to estimate the dynamics of a learning state vector. The algorithm is applied to decision response data recorded from non-human primates (NHPs) performing a Multiple-Choice Decision Task.


Assuntos
Tomada de Decisões , Algoritmos , Animais , Teorema de Bayes , Comportamento de Escolha , Aprendizagem
7.
J Res Health Sci ; 16(2): 90-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27497777

RESUMO

BACKGROUND: Necessity of evaluating heat stress in the workplace, require validation of indices and selection optimal index. The present study aimed to assess the precision and validity of some heat stress indices and select the optimum index for using in heavy work activities in hot and dry climates. METHODS: It carried out on 184 workers from 40 brick kilns workshops in the city of Qom, central Iran (as representative hot and dry climates). After reviewing the working process and evaluation the activity of workers and the type of work, environmental and physiological parameters according to standards recommended by International Organization for Standardization (ISO) including ISO 7243 and ISO 9886 were measured and indices were calculated. RESULTS: Workers engaged in indoor kiln experienced the highest values of natural wet temperature, dry temperature, globe temperature and relative humidity among studied sections (P<0.05). Indoor workplaces had the higher levels of all environmental parameters than outdoors (P=0.0001), except for air velocity. The wet-bulb globe temperature (WBGT) and heat stress index (HSI) indices had the highest correlation with other physiological parameters among the other heat stress indices. Relationship between WBGT index and carotid artery temperature (r=0.49), skin temperature (r=0.319), and oral temperature (r=0.203) was statistically significant (P=0.006). CONCLUSIONS: Since WBGT index, as the most applicable index for evaluating heat stress in workplaces is approved by ISO, and due to the positive features of WBGT such as ease of measurement and calculation, and with respect to some limitation in application of HSI; WBGT can be introduced as the most valid empirical index of heat stress in the brick workshops.


Assuntos
Temperatura Corporal , Monitoramento Ambiental/métodos , Transtornos de Estresse por Calor/etiologia , Temperatura Alta , Umidade , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Ar , Artérias Carótidas , Clima , Humanos , Irã (Geográfico) , Boca , Reprodutibilidade dos Testes , Pele , Trabalho
8.
Biol Trace Elem Res ; 146(1): 42-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21965109

RESUMO

The current study aimed to investigate if different sources of supplemental zinc (Zn), manganese (Mn), copper (Cu), and selenium (Se) fed to dry and lactating dairy cows affect reproductive performance, lameness status, and colostrum production. The experiment was carried out on 60 multiparous non-lactating Holstein cows in a commercial dairy herd. The cows received randomly mineral mixtures in three treatment groups containing inorganic, 25% organic-75% inorganic, or 50% organic-50% inorganic forms of Zn, Mn, Cu, and Se starting from approximately 3 weeks prior to calving up to 90 days postpartum. Supplements were included in rations and fed twice a day. Reproductive parameters including days to first service, days to first estrus, service per conception, and conception rate were investigated. After parturition, colostrum production, composition, and immunoglobulin G(1) concentration were determined. Lameness, as an indicator of trace minerals deficiency, was evaluated in a five-score scale. The source of mineral supplement only numerically improved the assessed parameters excluding colostrum fat, protein, and ash percent. The organic form of supplements did not significantly affect reproductive performance, lameness score, or colostrum production.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Doenças dos Bovinos/fisiopatologia , Bovinos/fisiologia , Colostro/metabolismo , Coxeadura Animal/fisiopatologia , Reprodução , Animais , Quelantes/farmacologia , Cobre/administração & dosagem , Suplementos Nutricionais , Feminino , Manganês/administração & dosagem , Selênio/administração & dosagem , Zinco/administração & dosagem
9.
Chaos ; 21(3): 033121, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21974656

RESUMO

Synchronization between two coupled complex networks with fractional-order dynamics, hereafter referred to as outer synchronization, is investigated in this work. In particular, we consider two systems consisting of interconnected nodes. The state variables of each node evolve with time according to a set of (possibly nonlinear and chaotic) fractional-order differential equations. One of the networks plays the role of a master system and drives the second network by way of an open-plus-closed-loop (OPCL) scheme. Starting from a simple analysis of the synchronization error and a basic lemma on the eigenvalues of matrices resulting from Kronecker products, we establish various sets of conditions for outer synchronization, i.e., for ensuring that the errors between the state variables of the master and response systems can asymptotically vanish with time. Then, we address the problem of robust outer synchronization, i.e., how to guarantee that the states of the nodes converge to common values when the parameters of the master and response networks are not identical, but present some perturbations. Assuming that these perturbations are bounded, we also find conditions for outer synchronization, this time given in terms of sets of linear matrix inequalities (LMIs). Most of the analytical results in this paper are valid both for fractional-order and integer-order dynamics. The assumptions on the inner (coupling) structure of the networks are mild, involving, at most, symmetry and diffusivity. The analytical results are complemented with numerical examples. In particular, we show examples of generalized and robust outer synchronization for networks whose nodes are governed by fractional-order Lorenz dynamics.

10.
J Hum Evol ; 52(4): 380-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17188739

RESUMO

The cooperative French-Iranian Paleoanthropological Project (FIPP) discovered three Paleolithic localities in Central Alborz, Northern Iran during its 2005 field mission. In the northern foothills near Baliran in Mazandârân province, Garm Roud yielded an open-air site with an archaeological layer attributable to the last glacial period that dates from the end of OIS 3 (28,486+/-190 cal BP). These geochronological data and the typo-technical observations converge to place the Garm Roud 2 assemblage in the Upper Paleolithic. Garm Roud 2 is thus the first site of this kind discovered in the area. In the southern foothills near Damâvand in Tehran province, Moghanak and Otchounak represent two open-air surface localities with lithic assemblages of Mousterian to Ante-Mousterian affinity. Garm Roud, Moghanak, and Otchounak provide some of the first direct field evidence of early human settlements in this central area of the Middle East.


Assuntos
Arqueologia , Geografia , Humanos , Irã (Geográfico)
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