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1.
Nanoscale ; 16(12): 6142-6150, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38444375

RESUMO

Two-dimensional (2D) materials have attracted significant attention owing to their distinctive electronic, thermal, and mechanical characteristics. Recent advancements in both theoretical understanding and experimental methods have greatly contributed to the understanding of thermoelectric properties in 2D materials. However, thermomagnetic properties of 2D materials have not yet received the same amount of attention. In this work, we select promising 2D materials guided by the physics of the Nernst effect and present a thorough first-principles study of their electronic structures, carrier mobilities, and Nernst coefficients as a function of carrier concentration. Specifically, we reveal that trilayer graphene with an ABA stacking exhibits an exceptionally large Nernst coefficient of 112 µV (KT)-1 at room temperature. We further demonstrate that monolayer graphene, ABC-stacked trilayer graphene, and trilayer phosphorene (AAA stacking) have large Nernst coefficients at room temperature. This study establishes an ab initio framework for the quantitative study of the thermomagnetic effects in 2D materials and demonstrates high fidelity with previous experimental data.

2.
Clin Ter ; 173(4): 362-368, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35857055

RESUMO

Background: The aim of this study is to investigate the effect of of 12 weeks of water aerobic exercise and atrovastain drug on apolipoproteins changes A1, ANP, BNP and CRP in older men with cardiovascular disesaes. Methods: In this study, we chose 40 patients with cardiovascular disease that were divideded in to four groups. Experimental groups selected exercise 3 times per weeks during 3 months with the method ofwalking on the water and carnal swimming. Results: The results were expressed as the mean ± sd, and all statistical comparisons were made by means of a one-way ANOVA test, followed by Tukey'sPost-Hoc analysis. Conclusion: The effect of exercise and intervention taking Atorvastatin increased Apolipoproteins A1changes, but reducedANP, BNP, and CRP, followed by the reduction of disease cardiovascular and improve cardiovascular function.


Assuntos
Fator Natriurético Atrial , Peptídeo Natriurético Encefálico , Idoso , Apolipoproteína A-I/metabolismo , Exercício Físico , Teste de Esforço , Humanos , Masculino , Receptores Imunológicos/análise , Água
3.
Clin Ter ; 173(3): 228-234, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35612337

RESUMO

Introduction: Endothelial progenitor cells (EPCs) play a role in preventing endothelial dysfunction and increasing the angiogenesis process. Regular training increases these cells. Turmeric Curcumin has anti-inflammatory and anti-atherosclerotic properties. Animal, Materials and Methods: 49 Wistar rats were randomly assigned to control (C), Saline (S), curcumin (cur), moderate interval training (MIT), high interval training (HIT), MIT+curAndHIT+cur. The training groups trained 8 weeks,3 sessions per week and 40 minutes each session at 28 and 34 m / min. 48 hours after the last training, The gene expression of the CD34 and KDR was measured by Real-time PCR and CRP usesthe ELISA method. Findings: CD34 and KDR mRNA in cur, MIT and HIT groups showed a significant increase compared to C and Sgroups.The highest levels of CD34 and KDR mRNA were observed in HIT+curgroup. While the increase of CD3 mRNA in HIT group was greater than the cur and MIT groups(P = 0.0001). KDR showed a significant increase in MIT and HIT groups compared to C, S, cur and MIT+cur groups. Serum CRP means significantly decreased in all experimental groups compared to C and S groups. Discussion and Conclusion: The rate of increase in EPCs mRNA in response to aerobic training is dependent on training intensity. HIT training is likely to be more effective in the repair and development of coronary arteries. These findings can be useful for cell therapy and improve cardiovascular regeneration after injury and myocardial disor-der, especially in elderly conditions.


Assuntos
Curcumina , Células Progenitoras Endoteliais , Idoso , Animais , Proteína C-Reativa/genética , Proteína C-Reativa/metabolismo , Curcumina/metabolismo , Curcumina/farmacologia , Células Progenitoras Endoteliais/metabolismo , Humanos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
4.
Phys Rev Mater ; 5(1)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34250434

RESUMO

Magneto-thermoelectric transport provides an understanding of coupled electron-hole-phonon current in topological materials and has applications in energy conversion and cooling. In this work, we study the Nernst coefficient, the magneto-Seebeck coefficient, and the magnetoresistance of single-crystalline Bi2Te3 under external magnetic field in the range of -3 T to 3 T and in the temperature range of 55 K to 380 K. Moreau's relation is employed to justify both the overall trend of the Nernst coefficient and the temperature at which the Nernst coefficient changes sign. We observe a non-linear relationship between the Nernst coefficient and the applied magnetic field in the temperature range of 55 K to 255 K. An increase in both the Nernst coefficient and the magneto-Seebeck coefficient is observed as the temperature is reduced which can be attributed to the increased mobility of the carriers at lower temperatures. First-principles density functional theory calculations were carried out to physically model the experimental data including electronic and transport properties. Simulation findings agreed with the experiments and provide a theoretical insight to justify the measurements.

5.
Domest Anim Endocrinol ; 77: 106647, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34311283

RESUMO

This study investigated the effects of dietary supplements of Zinc-Methionine (Zn-Met) on the zinc concentration of the blood and indices such as insulin resistance and glucose tolerance in late-pregnancy ewes to provide a practical solution to prevent metabolic diseases associated with energy status. In this research, 18 Makouei pregnant ewes were selected and randomized into 3 experimental groups: Group 1: Basal diet containing 10.3 mg Zn/kgDM and no zinc supplementation = CTR (Control); Group 2: Basal diet supplemented with low-dose zinc equivalent to the pregnancy requirements (30 mg Zn/kgDM) = LZN; Group 3: Basal diet supplemented with high-dose zinc (300 mg Zn/kgDM) = HZN. Blood samples for insulin resistance and glucose tolerance indices were collected according to standard methods. The results of this study indicated that supplementation of high-dose Zn-Met decreased (P < 0.05) blood glucose and tended (P < 0.1) to reduce the beta-hydroxybutyrate (BHB) concentrations. After intravenous injection of glucose and insulin, none of the glucose tolerance and insulin resistance indices were significant among groups (P > 0.05). However, the intravenous glucose tolerance test (IGTT) showed that the area under the curve (AUC) of serum glucose in the HZN group was numerically lower than that of the LZN and CTR groups. Furthermore, the numerically higher clearance rate (CR) of glucose and more negative glucose AUC following intravenous administration of insulin in Zinc-supplemented groups suggested that the ewes had greater insulin response than control group. The results showed a decrease in blood glucose concentration due to higher zinc intake after insulin injection and supported the evidence for improving insulin sensitivity. In addition, our results showed that ewes receiving zinc supplementation experienced a more favorable state of BHB or NEFA values. In conclusion, Zn-Met supplementation was found to have promising effects in improving energy metabolism in late pregnant ewes. However, further studies are needed to understand the mechanisms involved in regulating lipolysis and energy metabolism.


Assuntos
Resistência à Insulina , Animais , Glicemia , Suplementos Nutricionais , Ácidos Graxos não Esterificados , Feminino , Glucose , Insulina , Lactação/fisiologia , Metionina/farmacologia , Gravidez , Ovinos , Zinco/farmacologia
6.
Eur J Prosthodont Restor Dent ; 29(4): 218-222, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-33934578

RESUMO

PURPOSE: To evaluate the effects of arch size and implant angulation on the accuracy of implant impressions. MATERIALS AND METHODS: Four different resin models (small and large) of edentulous maxilla were fabricated and four implants were inserted (Blossom®, ø 4.75 × 10 mm) in each model. Implants were either parallel or angled 25° buccally. Forty working casts (small parallel, small angled, large parallel, and large angled) were fabricated in dental stone (n=10). For each implant, linear and angular displacements were measured using a coordinate-measuring machine (CMM) and mean values were analyzed by univariate analysis (α = 0.05). RESULTS: Arch size did not affect the linear or angular displacement (P ⟩ .05). However, the implant angulation had a marked influence on the linear displacement (P ⟨ .05). The largest linear displacement occurred in implant no. 4 of angled small groups. CONCLUSION: Regardless of arch size, linear and angular accuracy of implant impression varied with the implant angulation.


Assuntos
Implantes Dentários , Boca Edêntula , Materiais para Moldagem Odontológica , Técnica de Moldagem Odontológica , Humanos , Modelos Dentários
7.
J Helminthol ; 94: e115, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31931890

RESUMO

Drug resistance to helminth parasites is one of the most serious problems to threaten the livestock industry. The problem also poses a major threat to public health. Therefore, novel and safe agents should urgently be investigated to control parasitic infections. The current study was conducted to evaluate the possible antiparasitic effects of zinc oxide nanoparticles (ZnO-NPs) on one of the most prevalent gastrointestinal nematodes, Teladorsagia circumcincta. The worms were incubated with various concentrations of ZnO-NPs: 1, 4, 8, 12 and 16 ppm for 24 hours. Mobility and mortality of the parasites were recorded at four-hour intervals. At the endpoint, several biomarkers of oxidative/nitrosative stress, including superoxide dismutase, glutathione peroxidase and catalase, as well as lipid peroxidation, protein carbonylation, total antioxidant status, nitric oxide contents and DNA damage, were measured in the homogenized samples. ZnO-NPs showed significant anthelminthic effects, depending on time and concentration. Furthermore, the nanoparticle induced severe oxidative/nitrosative stress and DNA damage. ZnO-NPs could be considered as a novel and potent anthelminthic agent.


Assuntos
Anti-Helmínticos/farmacologia , Infecções por Nematoides/veterinária , Óxido de Zinco/farmacologia , Animais , Biomarcadores Farmacológicos , Dano ao DNA , Gado/parasitologia , Nanopartículas/parasitologia , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/parasitologia , Estresse Oxidativo
8.
PLoS One ; 14(7): e0220258, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339963

RESUMO

Implantable neural probes are widely used to record and stimulate neural activities. These probes should be stiff enough for insertion. However, it should also be flexible to minimize tissue damage after insertion. Therefore, having dynamic control of the neural probe shank flexibility will be useful. For the first time, we have successfully fabricated flexible neural probes with embedded microfluidic channels for dynamic control of neural probe stiffness by controlling fluidic pressure in the channels. The present hybrid neural probes consisted of polydimethylsiloxane (PDMS) and polyimide (PI) layers could provide the required stiffness for insertion and flexibility during operation. The PDMS channels were fabricated by reversal imprint using a silicon mold and bonded to a PI layer to form the embedded channels in the neural probe. The probe shape was patterned using an oxygen plasma generated by an inductively coupled plasma etching system. The critical buckling force of PDMS/PI neural probes could be tuned from 0.25-1.25 mN depending on the applied fluidic pressure in the microchannels and these probes were successfully inserted into a 0.6% agarose gel that mimicked the stiffness of the brain tissue. Polymer-based neural probes are typically more flexible than conventional metal wire-based probes, and they could potentially provide less tissue damage after implantation.


Assuntos
Dimetilpolisiloxanos/química , Eletrodos Implantados , Microfluídica/instrumentação , Neurônios/fisiologia , Resinas Sintéticas/química , Fenômenos Biomecânicos , Técnicas de Diagnóstico Neurológico/instrumentação , Desenho de Equipamento , Humanos , Teste de Materiais , Microtecnologia/métodos , Neurônios/efeitos dos fármacos , Maleabilidade , Polímeros/síntese química , Polímeros/química , Pressão
9.
ISA Trans ; 80: 503-512, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29891087

RESUMO

This paper presents a study on electro-hydraulic servo system for the purpose of position control using a compatible linear model. The system has high level of nonlinearity and linearization introduces extra error in system model. In order to reduce this error several methods of linearization uncertainty are discussed. In spite of applying Taylor's series for all methods, several procedures are used for considering uncertainty on linearization constants. In the first procedure, a simple bound is considered for each linearization constant. In the second procedure, a polytope is extracted for the uncertainty by a graphical method. Finally, a procedure with less conservativeness and less restriction is proposed. This procedure is used to extract the linear model of the electro-hydraulic servo system for the task of position control. The resulting model is used to synthesize an output-feedback H∞ controller for the EHSS using a Linear Matrix Inequality (LMI)-based approach. The effectiveness of the proposed method is demonstrated by simulation and experimental results. The results showed that the procedure is less conservative and has the fastest operation without any overshoot.

11.
Int Nurs Rev ; 65(3): 361-369, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29380381

RESUMO

AIM: This study aimed to summarize the available information in the literature to make an accurate estimate of the prevalence of burnout among Iranian nurses. BACKGROUND AND INTRODUCTION: Burnout is a work-related stress syndrome that has negative impact on healthcare providers, patients and healthcare delivery systems. METHOD: A comprehensive search of literature using international [PubMed, Scopus and the Institute for Scientific Information (ISI)] and Iranian scientific data bases [Scientific Information Database (SID), IranMedex and Magiran] was conducted to identify English and Persian language studies, published between 2000 and 2016, that examined the prevalence of burnout among nurses in Iran. The I-squared test and Chi-squared-based Q-test suggested heterogeneity of reported prevalence among the qualified studies; thus, a random-effects model was applied to estimate the overall prevalence of burnout among nurses in Iran. RESULTS: Based on 21 selected articles with 4180 participants, the overall prevalence of burnout among Iranian nurses was estimated to be 36% [95% confidence interval (CI), 20-53%] in Iran. Meta-regression indicated that sample size and year of data collection, mean age of samples, female to male ratio and geographic regions were not statistically significantly associated with the prevalence of burnout. Also, based on Egger's test and funnel plot, there is no publication bias among studies included in the analysis. CONCLUSION: Professional burnout affects more than one-third of nursing staff in Iran; thus, effective interventions and strategies are required to reduce and prevent burnout among nurses. IMPLICATION FOR NURSING AND HEALTH POLICY: Due to the negative consequences of burnout on patients, nurses and organizations, nursing and healthcare managers should intervene to prevent and reduce burnout among nurses in Iran. Policy attention should focus on developing effective interventions to prevent and minimize the burden of burnout among nurses in Iran. Nurses' involvement in the policy-making process is crucial in the implementation of effective programs and initiatives tailored to address the higher prevalence of burnout among Iranian nurses.


Assuntos
Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Esgotamento Psicológico/epidemiologia , Esgotamento Psicológico/psicologia , Recursos Humanos de Enfermagem/psicologia , Recursos Humanos de Enfermagem/estatística & dados numéricos , Adulto , Feminino , Humanos , Irã (Geográfico)/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência
12.
ISA Trans ; 73: 154-164, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30686294

RESUMO

Electro-Hydraulic Servo Systems (EHSS) are employed as actuators to track the desired trajectory and exert force in heavy-duty industrial applications. The EHSS is often prone to problems such as leakage and actuator seal damage during the course of its utilization. These faults which cannot be directly detected from current sensor values, can eventually result in complications and degrade control performance. The goal of this research is to use representation learning concepts to detect these faults with decreased complexity. The objective is to find a nonlinear mapping to transform raw data into another space in which classification becomes easier. The data are driven from the hydraulic supply pressure signal. To find the mapping, a custom-built optimization algorithm is proposed along with a suitable cost function to carry out the search for the new representation. The performance of the resulting transformation is tested in an experimental setting to show the merits of the proposed method.

13.
Curr Med Mycol ; 3(1): 20-24, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29302626

RESUMO

BACKGROUND AND PURPOSE: The epidemiological features of dermatophytoses have been characterized in many geographical locations of Iran, but not in Guilan, North of Iran. This study was carried out to determine the distribution pattern of dermatophytoses and their relevant agents in Guilan, North of Iran, over a period of one year, from April 2010 to April 2011. MATERIALS AND METHODS: The clinical samples of skin, hair, and nail from 889 outpatients (317 men vs. 572 women) were used for direct microscopy and culture. All the culture-positive samples were then subjected to amplification of the internal transcribed spacer (ITS) of the nuclear rDNA followed by a restriction fragment length polymorphism (RFLP) assay to verify the causative agents. RESULTS: The infection was confirmed in 90 (44.3%) males and 113 (55.7%) females. The most common type of dermatophytoses was tinea cruris (42.9%), followed by tinea pedis (20.2%), tinea corporis (11.3%), tinea unguium (7.4%), tinea faciei (6.9%), tinea manuum (6.4%), and tinea capitis (4.9%). ITS-RFLP based of the identification of isolates, showed that the infections were significantly associated with anthropophilic species, of Trichophyton rubrum (41.9%), Epidermophyton floccosum (19.7%), T. tonsurans (5.4%), and T.violaceum (2%). Other causative agents were T. interdigitale (22.6%), Microsporum canis (4.9%), T. verrucosum (2.5%), and M. gypseum (1%). CONCLUSION: The higher prevalence of T. rubrum, as the agent of dermatophytoses, than other species has never been reported from Iran and is of public health concern because of the chronic nature of infections with anthropophilic species. To thoroughly investigate the epidemiological trend of dermatophytoses in Iran, further periodical and molecular-based studies are necessary.

14.
East Mediterr Health J ; 22(1): 19-26, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27117646

RESUMO

This study aimed to evaluate inequalities in the geographical distribution of human and physical resources in the health sector of Kermanshah province, Islamic Republic of Iran. In a retrospective, cross-sectional study, data from the Statistical Centre of Iran were used to calculate inequality measures (Gini coefficient and index of dissimilarity) over the years 2005-11. The highest Gini coefficient for human resources was observed for pharmacists in 2005 (0.75) and the lowest for paramedics in 2010 and 2011 (0.10). The highest indices of dissimilarity were also for pharmacists in 2005 (29%) and paramedics in 2011 (3%). For physical resources, the highest and lowest Gini coefficients were for rehabilitation centres in 2010 (0.59) and health houses in 2011 (0.12) respectively. Generally, inequalities in the distribution of health care resources were lower at the end of the study period, although there was potential for more equitable distribution of pharmacists, specialists, health houses and beds.


Assuntos
Recursos em Saúde/provisão & distribuição , Disparidades em Assistência à Saúde , Estudos Transversais , Humanos , Irã (Geográfico) , Estudos Retrospectivos
15.
Br Poult Sci ; 57(1): 71-83, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26654967

RESUMO

A 42-d trial was conducted to investigate the effect of adding a synbiotic supplement to diets containing two different types of fat on performance, blood lipids and fatty acid (FA) composition and oxidative stability of breast and thigh meat in broilers. A total of 800 one-d-old male broiler chickens were randomly assigned into 1 of 8 treatments with 4 replicates of 25 birds per treatment. The experiment consisted of a 4 × 2 factorial arrangement of treatments including 4 concentrations of synbiotic (0, 0.5, 1 or 1.5 g/kg diet) and 2 types of fat [sunflower oil (SO) or canola oil (CO)] at an inclusion rate of 50 g/kg diet. Dietary fat type did not affect body weight gain (BWG) or feed conversion ratio (FCR) during the overall experimental period (0-42 d). However, fat type modified serum lipid profile and FA composition and 2-thiobarbituric acid-reactive substances (TBARS) content in breast and thigh meat. The addition of synbiotic to the diet linearly improved overall BWG and FCR and also decreased serum cholesterol and low-density lipoprotein cholesterol concentrations. The TBARS value in thigh meat after 30 d of storage at 4°C was linearly decreased as the synbiotic inclusion concentrations in the diets increased. Dietary synbiotic also decreased the proportion of monounsaturated fatty acids and increased n-6 polyunsaturated fatty acid (PUFA) concentration in thigh meat, whereas the FA profile of breast meat was not affected by synbiotic supplementation. Moreover, the PUFA/SFA ratio in the breast meat was linearly increased when synbiotic was included in the CO-containing diets. In conclusion, the addition of synbiotic to broiler diets had a positive effect on growth performance, blood lipid profile and meat quality. The results also support the use of synbiotic to increase the capacity of canola oil for enhancing PUFA/SFA ratio of breast meat in broilers.


Assuntos
Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Enterococcus faecium/classificação , Inulina/metabolismo , Carne/análise , Músculos Peitorais/efeitos dos fármacos , Simbióticos/análise , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Análise Química do Sangue/veterinária , Dieta/veterinária , Relação Dose-Resposta a Droga , Ácidos Graxos Ômega-3/metabolismo , Ácidos Graxos Ômega-6/metabolismo , Inulina/administração & dosagem , Masculino , Músculos Peitorais/fisiologia , Distribuição Aleatória , Simbióticos/administração & dosagem
16.
Domest Anim Endocrinol ; 53: 95-102, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26201762

RESUMO

This study aimed to evaluate the effects of intravenous infusion of a soybean-based lipid emulsion on some blood energy-related metabolites and insulin sensitivity indexes in sheep. Four clinically healthy ewes were assigned into a 2-treatment, 2-period cross-over design. Either normal saline (NS) or lipid emulsion (LE) was intravenously introduced at a rate of 0.025 mL·kg(-1) min(-1) for 6 h. The concentrations of blood nonesterified fatty acid (NEFA), beta-hydroxybutyrate, triglyceride, cholesterol, urea, creatinine, cortisol, glucose, and insulin were measured at different time points. After 6 h, intravenous glucose tolerance test was performed. Lipid infusion elicited an increase (P < 0.05) in the NEFA, beta-hydroxybutyrate, and triglyceride concentrations compared with the baseline value and NS infusion. Infusion of NS did not influence blood glucose concentration; however, LE infusion increased plasma glucose concentration (P < 0.05). At time point 12 h, serum insulin concentrations were increased (P < 0.05) in NS treatment; however, such an increase was not observed in the LE treatment. Insulin sensitivity index for the LE infusion was lower (P < 0.05) than that for the NS treatment. The glucose effectiveness was not (P > 0.05) different among treatments. In the LE treatment, acute-phase insulin responses increased (P < 0.05) and disposition index decreased (P < 0.001) compared with NS treatment. The results showed that experimentally induced NEFA in blood could cause insulin resistance in sheep. The current model could be used to evaluate the pathogenesis of conditions associated with increased lipid mobilization and insulin resistance.


Assuntos
Emulsões Gordurosas Intravenosas/efeitos adversos , Hiperlipidemias/veterinária , Resistência à Insulina/fisiologia , Doenças dos Ovinos/induzido quimicamente , Animais , Teste de Tolerância a Glucose/veterinária , Hiperlipidemias/induzido quimicamente , Ovinos
17.
ISA Trans ; 53(6): 1873-80, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25160870

RESUMO

Electro-hydraulic servo systems (EHSS) are used in many industrial applications for position and force control. Force control with a hydraulic actuator is challenging and requires complicated control algorithms used along with high crossover frequency electro-hydraulic valves, even for simple force control tasks. In this paper, a different hydraulic structure is proposed to improve the force tracking quality and increase efficiency in the EHSS. This comes at the cost of a new model with linearization and uncertainty challenges. To address these challenges, a robust H∞ control design approach is followed to control the proposed EHSS. Model linearization uncertainties are approximated by a polytope and a robust controller is designed to keep the system stable and satisfy the H∞ performance conditions within this polytope. Experimental results verify that the objectives of the paper are satisfied after using the proposed system.

18.
ISA Trans ; 53(4): 1297-306, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24882668

RESUMO

The electro-hydraulic servo system (EHSS) demonstrates a relatively low level of efficiency compared to other available actuation methods. The objective of this paper is to increase this efficiency by introducing a variable supply pressure into the system and controlling this pressure during the task of position tracking. For this purpose, an EHSS structure with controllable supply pressure is proposed and its dynamic model is derived from the basic laws of physics. A switching control structure is then proposed to control both the supply pressure and the cylinder position at the same time, in a way that reduces the overall energy consumption of the system. The stability of the proposed switching control system is guaranteed by proof, and its performance is verified by experimental testing.

19.
J Helminthol ; 88(4): 385-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23656910

RESUMO

Trichinellosis is an important helminthic food-borne zoonosis, which is caused by nematodes of the genus Trichinella. Although, Trichinella spp. has been detected frequently in Iranian wildlife, this parasitic infection is not considered a major public health problem. This is largely because Islamic codes forbid consumption of pork meat in this country. However, knowledge about this zoonotic pathogen is important because human trichinellosis has been documented in countries where most of the population is Muslim. The aims of the present work were to investigate whether Trichinella spp. was still circulating in wildlife of the Khuzestan Province (south-west Iran) about 30 years after the first investigation, to identify the aetiological agent at the species level by molecular analyses, and to review the literature on Trichinella spp. in animals of Iran. During the winter 2009-2010, muscle samples from 32 road-killed animals (14 dogs and 18 jackals, Canis aureus) were collected. Muscle samples were digested and Trichinella sp. larvae were isolated from two jackals. The Trichinella sp. larvae have been identified as Trichinella britovi by molecular analyses. These results confirm that T. britovi is the prevalent species circulating in wild animals of Iran.


Assuntos
Chacais , Trichinella/isolamento & purificação , Triquinelose/veterinária , Animais , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Irã (Geográfico)/epidemiologia , Trichinella/classificação , Trichinella/genética , Triquinelose/epidemiologia , Triquinelose/parasitologia
20.
Andrology ; 1(4): 607-14, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23785021

RESUMO

The purpose of this study was to evaluate the seminal 8-Isoprostane, reactive oxygen species (ROS), malondialdehyde (MDA), superoxide dismutase (SOD), catalase, total antioxidant capacity (TAC) in subjects with different level of physical fitness. A total of 161 semen samples were obtained from three groups of healthy males, including elite athletes (23.8 ± 5.2 years, n = 56) who had regular training (4-5 days per week), recreationally active men (24.2 ± 4.9 years, n = 52) who participated in educational or recreational physical activities for 4-5 h per week and non-active men (23.9 ± 5.0 years, n = 53) who did not participate in any exercise programmes for at least 6 months prior to the study. The results showed significantly higher levels of SOD, catalase and TAC as well as lower levels of 8-Isoprostane, ROS and MDA in recreationally active men compared with either elite athletes or non-active men (p < 0.001). Also, elite athletes revealed significantly higher seminal 8-Isoprostane, ROS and MDA as well as lower SOD, catalase and TAC levels compared with recreationally active and non-active men (p < 0.001). In conclusion, the results of the present study indicate that there are differences in seminal oxidants and antioxidants of elite athletes, recreationally active and non-active men. These differences are more likely related to indices that favour decrement of oxidative stress-induced peroxidative damage in spermatozoa from recreationally active men. Hence, recreationally active men seem to have a healthier semen production. The physiological significance of this observation is worthy of further investigation.


Assuntos
Antioxidantes/análise , Oxidantes , Estresse Oxidativo , Aptidão Física , Sêmen/química , Adolescente , Adulto , Análise de Variância , Biomarcadores/análise , Catalase/análise , Dinoprosta/análogos & derivados , Dinoprosta/análise , Teste de Esforço , Humanos , Masculino , Malondialdeído/análise , Espécies Reativas de Oxigênio/análise , Análise do Sêmen , Superóxido Dismutase/análise , Adulto Jovem
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