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1.
Acta Psychol (Amst) ; 248: 104367, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38905950

RESUMO

As various contextual and individual difference factors determine how and when mindsets may influence learning outcomes, burgeoning L2 research has recently addressed the role of growth language mindset (GLM) in different learning outcomes such as L2 Willingness to Communicate (WTC). Since little is known about the underlying mechanism through which GLM may contribute to WTC, a highly desirable goal of L2 education and an important criterion for assessing its efficiency and success, the present study addresses this gap by investigating the possible mediating and moderating roles of linguistic risk taking and L2 learning experience, respectively. The participants were 392 Iranian L2 students chosen by multi-stage cluster sampling. Findings showed that GLM predicted WTC directly and positively, and their association was mediated and moderated by linguistic risk taking (an important affective factor) and L2 learning experience (an essential motivational factor), respectively. Suggestions for future studies and implications for promoting learners' GLM, linguistic risk taking, and L2 learning experience are presented.

2.
Acta Psychol (Amst) ; 247: 104315, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38749273

RESUMO

Are teachers with better quality of work life (QWL) more innovative, and why? This study examined the relationship between teachers' QWL and their innovative behaviours, alongside the potential underlying mechanisms through psychological empowerment and teaching mindsets. A total of 321 elementary teachers completed a questionnaire. Path analysis demonstrated a significant positive association between QWL and innovative teaching behaviours. Moreover, both psychological empowerment and teaching mindsets significantly mediated this relationship. Specifically, teachers with higher QWL showed greater psychological empowerment and embraced stronger growth mindsets about their teaching abilities, which enables them to become more innovative in their teaching approaches. These findings suggest that quality of work life is not just a matter of teachers' well-being, but it also plays an important role in their teaching quality, which can ultimately benefit the institutions and the students.


Assuntos
Qualidade de Vida , Professores Escolares , Ensino , Humanos , Feminino , Masculino , Adulto , Qualidade de Vida/psicologia , Inquéritos e Questionários , Pessoa de Meia-Idade , Criatividade , Poder Psicológico
3.
Nanoscale ; 16(23): 11296-11309, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38787737

RESUMO

The study of titanium dioxide (TiO2) in the brookite phase is gaining popularity as evidence has shown the efficient photocatalytic performance of this less investigated polymorph. It has been recently reported that defective anisotropic brookite TiO2 nanorods display remarkable substrate-specific reactivity towards alcohol photoreforming, with rates of hydrogen production significantly (18-fold) higher than those exhibited by anatase TiO2 nanoparticles. To elucidate the basic photo-physical mechanisms and peculiarities leading to such an improvement in the photoactive efficiency, we investigated the recombination processes of photoexcited charge carriers in both stoichiometric and reduced brookite nanorods via photoluminescence excitation spectroscopy in controlled environment. Through an investigation procedure employing both supragap and subgap excitation during successive exposure to oxidizing and reducing gaseous agents, we firstly obtained an interpretation scheme describing the main photoluminescence and charge recombination pathways in stoichiometric and reduced brookite, which includes information about the spatial and energetic position of the intragap states involved in photoluminescence mechanisms, and secondly identified a specific photoluminescence enhancement process occurring in only reduced brookite nanorods, which indicates the injection of a conduction band electron during ethanol photo-oxidation. The latter finding may shed light on the empirical evidence about the exceptional reactivity of reduced brookite nanorods toward the photo-oxidation of alcohols and the concomitant efficiency of photocatalytic hydrogen generation.

4.
Comput Methods Biomech Biomed Engin ; 27(5): 651-679, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37068041

RESUMO

The purpose of this article is to investigate the optimal control of nonlinear fractional order chaotic models of diabetes mellitus, human immunodeficiency virus, migraine and Parkinson's diseases using genetic algorithms and particle swarm optimization. Mathematical chaotic models of nonlinear fractional order type of the above diseases were presented. Then optimal control for each of the models and numerical simulation was done using genetic algorithm and particle swarm optimization algorithm. The results of the genetic algorithm method are excellent. All the results obtained for the particle swarm optimization method show that this method is also very successful and the results are very close to the genetic algorithm method. Very low values of MSE and RMSE errors indicate that the simulation is effective and efficient. Also, Lie symmetry was calculated for the proposed models and the results were presented.


Assuntos
Diabetes Mellitus , Doença de Parkinson , Humanos , HIV , Algoritmos , Modelos Teóricos , Simulação por Computador
5.
J Psycholinguist Res ; 52(6): 2955-2978, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37935808

RESUMO

The important role of willingness to communicate (WTC) in facilitating second language (L2) learning and use has been widely endorsed. However, few studies have examined how teacher support in an L2 class may predict students' L2 WTC. Such a relationship may also be mediated by learners' L2 anxiety, a typical predictor of L2 WTC, and moderated by learners' beliefs about the malleability of their language learning ability, a construct known as growth language mindset. Framed from the Control-Value Theory (Pekrun, in Educ Psychol Rev 18(4):315-341, 2006) and the Language-Mindset Meaning System (Lou and Noels, in: Lamb, Csizér, Henry, Ryan (eds) The Palgrave handbook of motivation for language learning, Palgrave Macmillan, 2019a, System 86:102126, 2019b), this study aimed to investigate the relationships between teacher support, L2 anxiety, growth language mindset, and L2 WTC. The data were collected from 551 English-as-a-Foreign-Language (EFL) learners in Iran and analyzed using structural equation modeling (SEM). The results showed that teacher support was directly and positively associated with L2 WTC, and this relationship was significantly mediated by L2 anxiety. The relationship between teacher support and L2 WTC, however, was only significant among learners with medium and high levels of growth language mindset. In addition, growth language mindset also moderated the negative relationship between L2 anxiety and L2 WTC, with this relationship being weaker among learners with higher levels of growth language mindset. Finally, theoretical and pedagogical implications and directions for future research are presented.


Assuntos
Ansiedade , Idioma , Humanos , Cognição , Desenvolvimento da Linguagem , Aprendizagem
6.
ACS Photonics ; 10(9): 3291-3301, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37743938

RESUMO

We report a quasi-unitary broadband absorption over the ultraviolet-visible-near-infrared range in spaced high aspect ratio, nanoporous titanium oxynitride nanotubes, an ideal platform for several photothermal applications. We explain such an efficient light-heat conversion in terms of localized field distribution and heat dissipation within the nanopores, whose sparsity can be controlled during fabrication. The extremely large heat dissipation could not be explained in terms of effective medium theories, which are typically used to describe small geometrical features associated with relatively large optical structures. A fabrication-process-inspired numerical model was developed to describe a realistic space-dependent electric permittivity distribution within the nanotubes. The resulting abrupt optical discontinuities favor electromagnetic dissipation in the deep sub-wavelength domains generated and can explain the large broadband absorption measured in samples with different porosities. The potential application of porous titanium oxynitride nanotubes as solar absorbers was explored by photothermal experiments under moderately concentrated white light (1-12 Suns). These findings suggest potential interest in realizing solar-thermal devices based on such simple and scalable metamaterials.

7.
ACS Appl Mater Interfaces ; 15(31): 37976-37985, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37490013

RESUMO

Single-atom catalysts (SACs) have demonstrated superior catalytic activity and selectivity compared to nanoparticle catalysts due to their high reactivity and atom efficiency. However, stabilizing SACs within hosting substrates and their controllable loading preventing single atom clustering remain the key challenges in this field. Moreover, the direct comparison of (co-) catalytic effect of single atoms vs nanoparticles is still highly challenging. Here, we present a novel ultrasound-driven strategy for stabilizing Pt single-atomic sites over highly ordered TiO2 nanotubes. This controllable low-temperature defect engineering enables entrapment of platinum single atoms and controlling their content through the reaction time of consequent chemical impregnation. The novel methodology enables achieving nearly 50 times higher normalized hydrogen evolution compared to pristine titania nanotubes. Moreover, the developed procedure allows the decoration of titania also with ultrasmall nanoparticles through a longer impregnation time of the substrate in a very dilute hexachloroplatinic acid solution. The comparison shows a 10 times higher normalized hydrogen production of platinum single atoms compared to nanoparticles. The mechanistic study shows that the novel approach creates homogeneously distributed defects, such as oxygen vacancies and Ti3+ species, which effectively trap and stabilize Pt2+ and Pt4+ single atoms. The optimized platinum single-atom photocatalyst shows excellent performance of photocatalytic water splitting and hydrogen evolution under one sun solar-simulated light, with TOF values being one order of magnitude higher compared to those of traditional thermal reduction-based methods. The single-atom engineering based on the creation of ultrasound-triggered chemical traps provides a pathway for controllable assembling stable and highly active single-atomic site catalysts on metal oxide support layers.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37145154

RESUMO

Recent advances in optimal diabetes control have made it possible for diabetic patients to live longer, healthier, and happier lives. In this research, particle swarm optimization and genetic algorithm are applied in order to control the non-linear fractional order chaotic system of glucose-insulin optimally. A fractional system of differential equations discussed the chaotic behavior of the growth of the blood glucose system. Particle swarm optimization and genetic algorithm were used to solve the presented optimal control problem. The results showed that when the controller is applied from the beginning, the results of the genetic algorithm method are excellent. All the results obtained for the particle swarm optimization method show that this method is also very successful and the results are very close to the genetic algorithm method.

9.
Adv Biomed Res ; 12: 67, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37200741

RESUMO

Background: Cutaneous leishmaniasis (CL) is an ulcerative skin disease caused by some species of the genus Leishmania. Evidence shows that Perovskia abrotanoides is an important herbal medicine against Leishmania. This study was conducted to investigate the killing effect of terpenoid-rich fractions on promastigotes of L. major (MRHO/IR/75/ER). Material and Method: The eluates of reverse phased medium pressure liquid chromatography (RP-MPLC) of the extract were subjected to thin-layer chromatography (TLC) and categorized into six final fractions. Primary proton nuclear magnetic resonance (H-NMR) spectroscopy confirmed fractions' nature. Fractions 4, 5, and 6 (F4, F5, F6) were identified as terpenoid-rich content. Two concentrations of 50 and 100 µg/ml were prepared to test leishmanicidal activity. Followed by treating promastigotes of L. major by the fractions in incubation times of 12, 24, and 48 hours, their viability was determined using a cell proliferation MTS ((3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. Result: F4, F5, and F6 showed significant killing activity on promastigotes of L. major in a concentration-dependent manner. The viability of promastigotes was significantly reduced at a concentration of 100 µg/ml compared to 50 µg/ml (P-value <0.05). Also, over time a significant decreasing trend in the viability of promastigotes confirmed the time-dependent manner of the fractions (P-value <0.01). Furthermore, F5 had the highest leishmanicidal activity at the first incubation time compared with other fractions. Conclusion: Terpenoid-rich fractions of the P. abrotanoides have a leishmanicidal activity that depends on time and concentration. Among them, F5 has the highest potency that may contain potent terpenoid constituents.

10.
Phys Rev Lett ; 130(3): 034001, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36763387

RESUMO

The presence of submicrometer structures at liquid-fluid interfaces modifies the properties of many science and technological systems by lowering the interfacial tension, creating tangential Marangoni stresses, and/or inducing surface viscoelasticity. Here we experimentally study the break-up of a liquid filament of a silica nanoparticle dispersion in a background oil phase that contains surfactant assemblies. Although self-similar power-law pinch-off is well documented for threads of Newtonian fluids, we report that when a viscoelastic layer is formed in situ at the interface, the pinch-off dynamics follows an exponential decay. Recently, such exponential neck thinning was found theoretically when surface viscous effects were taken into account. We introduce a simple approach to calculate the effective relaxation time of viscoelastic interfaces and estimate the thickness of the interfacial layer and the viscoelastic properties of liquid-fluid interfaces, where the direct measurement of interfacial rheology is not possible.

11.
Nat Commun ; 13(1): 4162, 2022 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851272

RESUMO

Printing a structured network of functionalized droplets in a liquid medium enables engineering collectives of living cells for functional purposes and promises enormous applications in processes ranging from energy storage to tissue engineering. Current approaches are limited to drop-by-drop printing or face limitations in reproducing the sophisticated internal features of a structured material and its interactions with the surrounding media. Here, we report a simple approach for creating stable liquid filaments of silica nanoparticle dispersions and use them as inks to print all-in-liquid materials that consist of a network of droplets. Silica nanoparticles stabilize liquid filaments at Weber numbers two orders of magnitude smaller than previously reported in liquid-liquid systems by rapidly producing a concentrated emulsion zone at the oil-water interface. We experimentally demonstrate the printed aqueous phase is emulsified in-situ; consequently, a 3D structure is achieved with flexible walls consisting of layered emulsions. The tube-like printed features have a spongy texture resembling miniaturized versions of "tube sponges" found in the oceans. A scaling analysis based on the interplay between hydrodynamics and emulsification kinetics reveals that filaments are formed when emulsions are generated and remain at the interface during the printing period. Stabilized filaments are utilized for printing liquid-based fluidic channels.


Assuntos
Nanopartículas , Dióxido de Silício , Emulsões/química , Tinta , Nanopartículas/química , Água/química
12.
Nat Commun ; 13(1): 3085, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35654770

RESUMO

The evaporation of particle-laden sessile droplets is associated with capillary-driven outward flow and leaves nonuniform coffee-ring-like particle patterns due to far-from-equilibrium effects. Traditionally, the surface energies of the drop and solid phases are tuned, or external forces are applied to suppress the coffee-ring; however, achieving a uniform and repeatable particle deposition is extremely challenging. Here, we report a simple, scalable, and noninvasive technique that yields uniform and exceptionally ordered particle deposits on a microscale surface area by placing the droplet on a near neutral-wet shadow mold attached to a hydrophilic substrate. The simplicity of the method, no external forces, and no tuning materials' physiochemical properties make the present generic approach an excellent candidate for a wide range of sensitive applications. We demonstrate the utility of this method for fabricating ordered mono- and multilayer patternable coatings, producing nanofilters with controlled pore size, and creating reproducible functionalized nanosensors.

13.
Sci Rep ; 11(1): 15404, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34321592

RESUMO

This work develops a robust classifier for a COVID-19 pre-screening model from crowdsourced cough sound data. The crowdsourced cough recordings contain a variable number of coughs, with some input sound files more informative than the others. Accurate detection of COVID-19 from the sound datasets requires overcoming two main challenges (i) the variable number of coughs in each recording and (ii) the low number of COVID-positive cases compared to healthy coughs in the data. We use two open datasets of crowdsourced cough recordings and segment each cough recording into non-overlapping coughs. The segmentation enriches the original data without oversampling by splitting the original cough sound files into non-overlapping segments. Splitting the sound files enables us to increase the samples of the minority class (COVID-19) without changing the feature distribution of the COVID-19 samples resulted from applying oversampling techniques. Each cough sound segment is transformed into six image representations for further analyses. We conduct extensive experiments with shallow machine learning, Convolutional Neural Network (CNN), and pre-trained CNN models. The results of our models were compared to other recently published papers that apply machine learning to cough sound data for COVID-19 detection. Our method demonstrated a high performance using an ensemble model on the testing dataset with area under receiver operating characteristics curve = 0.77, precision = 0.80, recall = 0.71, F1 measure = 0.75, and Kappa = 0.53. The results show an improvement in the prediction accuracy of our COVID-19 pre-screening model compared to the other models.


Assuntos
COVID-19/diagnóstico , Tosse/classificação , COVID-19/epidemiologia , Tosse/virologia , Aprendizado Profundo , Humanos , Aprendizado de Máquina , Programas de Rastreamento/métodos , Redes Neurais de Computação , Curva ROC , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade , Som , Espectrografia do Som/métodos , Tomografia Computadorizada por Raios X/métodos
14.
J Colloid Interface Sci ; 587: 510-521, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33406465

RESUMO

HYPOTHESIS: Traditionally, double emulsions are produced in the presence of both oil-soluble and water-soluble surfactants in sequential droplet formation settings or unique fluidic designs. Micelles, assemblies of surfactants in liquid mediums, can generate single emulsion droplets without requiring input energy. We hypothesize that the synergy between nanoparticles in one phase, and micelles in the other phase can spontaneously generate double emulsions. Nanoparticles can become surface-activated by adsorbing surfactants and form the second type of emulsions from the initially emulsified phase by micelles. EXPERIMENTS: We design a thermodynamically-driven emulsification platform where double emulsions are spontaneously formed as soon an aqueous nanoparticle dispersion is placed in contact with an oleic micellar solution. Confocal and cryogenic-scanning electron microscopies are utilized to characterize structure and intensity of emulsions at various concentrations of silica nanoparticle and Span micelles. The rate of particle surface activation and emulsification and the amount of water intake are quantified using dynamic light scattering, dynamic interfacial tension, and density measurements. FINDINGS: Nanoscale water droplets nucleate in the oil in form of swollen micelles. Over time, nanoparticles form a water-shell encapsulating the swollen-micelle rich oil phase. The gradual surfaceactivation of nanoparticles is key in self-double emulsification and controlling the emulsion intensity. We build on this new discovery and design a novel system for double emulsification. Incorporating nanoparticles into spontaneous emulsification systems opens novel routes for designing emulsion-based materials.

15.
Water Res ; 175: 115676, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32193027

RESUMO

The fluid flow, species transport, and chemical reactions in geological formations are the chief mechanisms in engineering the exploitation of fossil fuels and geothermal energy, the geological storage of carbon dioxide (CO2), and the disposal of hazardous materials. Porous rock is characterized by a wide surface area, where the physicochemical fluid-solid interactions dominate the multiphase flow behavior. A variety of visual models with differences in dimensions, patterns, surface properties, and fabrication techniques have been widely utilized to simulate and directly visualize such interactions in porous media. This review discusses the six categories of visual models used in geological flow applications, including packed beds, Hele-Shaw cells, synthesized microchips (also known as microfluidic chips or micromodels), geomaterial-dominated microchips, three-dimensional (3D) microchips, and nanofluidics. For each category, critical technical points (such as surface chemistry and geometry) and practical applications are summarized. Finally, we discuss opportunities and provide a framework for the development of custom-built visual models.


Assuntos
Dióxido de Carbono , Geologia , Física , Porosidade , Propriedades de Superfície
16.
Curr Oncol ; 26(4): 234-239, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31548802

RESUMO

Background: Expert groups have recommended incorporation of a geriatric assessment into clinical practice for older patients starting oncologic therapy. However, that practice is not standard primarily because of resource limitations. In the present study, we evaluated the effect on treatment decisions by oncologists in the community oncology setting of a brief geriatric assessment tool that estimates risk of toxicity. Methods: This prospective longitudinal study in 5 community oncology practices in British Columbia involved patients 70 years of age and older starting a new cytotoxic chemotherapy regimen. Clinical personnel completed a brief validated geriatric assessment tool-the Cancer and Aging Research Group chemotherapy toxicity tool (carg-tt)-that estimates the risk of grade 3 or greater toxicity in older patients. Physicians were asked if the carg-tt changed their treatment plan or prompted extra supports. Patients were followed to assess the incidence of toxicity during treatment. Results: The study enrolled 199 patients between July 2016 and February 2018. Mean age was 77 years. Treatment was palliative in 61.4% of the group. Compared with physician judgment, the carg-tt predicted higher rates of toxicity. In 5 patients, treatment was changed based on the carg-tt. In 38.5% of the patients, data from the tool prompted extra supports. Within the first 3 cycles of treatment, 21.3% of patients had experienced grade 3 or greater toxicity. Conclusions: This study demonstrates that use of a brief geriatric assessment tool is possible in a broad community oncology practice. The tool modified the oncologist's supportive care plan for a significant number of older patients undertaking cytotoxic chemotherapy.


Assuntos
Antineoplásicos/efeitos adversos , Avaliação Geriátrica/métodos , Neoplasias/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Colúmbia Britânica , Tomada de Decisão Clínica , Feminino , Humanos , Estudos Longitudinais , Masculino , Cuidados Paliativos/estatística & dados numéricos , Estudos Prospectivos , Medição de Risco
17.
Phys Rev E ; 97(6-1): 063104, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30011490

RESUMO

This paper reports the experimental results of a water droplet spreading on a glass substrate submerged in an oil phase. The radius of the wetted area grows exponentially over time forming two distinct regimes. The early time dynamics of wetting is characterized with the time exponent of 1, referred to as the viscous regime, which is ultimately transitioned to the Tanner's regime with the time exponent of 0.1. It is revealed that an increase in the ambient phase viscosity over three decades considerably slows down the rate of three-phase contact line movement. A scaling law is developed where the three-phase contact line velocity is a function of both spreading radius and mean viscosity, close to the geometric mean of the droplet and ambient fluids' viscosities. Using the proposed scaling and mean viscosity, all plots of spreading radius for different viscosity ratios collapse to a master curve. Furthermore, several cases with multiple rupture and spreading points, i.e., wetting in a nonideal system, are considered. The growth of an equivalent wetting radius in a multiple point spreading system is predicted by the developed scaling law.

18.
Sci Rep ; 8(1): 139, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29317767

RESUMO

A novel flow sensor is presented to measure the flow rate within microchannels in a real-time, noncontact and nonintrusive manner. The microfluidic device is made of a fluidic microchannel sealed with a thin polymer layer interfacing the fluidics and microwave electronics. Deformation of the thin circular membrane alters the permittivity and conductivity over the sensitive zone of the microwave resonator device and enables high-resolution detection of flow rate in microfluidic channels using non-contact microwave as a standalone system. The flow sensor has the linear response in the range of 0-150 µl/min for the optimal sensor performance. The highest sensitivity is detected to be 0.5 µl/min for the membrane with the diameter of 3 mm and the thickness of 100 µm. The sensor is reproducible with the error of 0.1% for the flow rate of 10 µl/min. Furthermore, the sensor functioned very stable for 20 hrs performance within the cell culture incubator in 37 °C and 5% CO2 environment for detecting the flow rate of the culture medium. This sensor does not need any contact with the liquid and is highly compatible with several applications in energy and biomedical engineering, and particularly for microfluidic-based lab-on-chips, micro-bioreactors and organ-on-chips platforms.

19.
Trop Biomed ; 35(1): 82-90, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33601780

RESUMO

Dogs can act as reservoirs, carriers, and transmitters of several zoonotic intestinal parasites that can cause serious health problems for humans. The aim of this study was to determine the prevalence of intestinal parasites in dogs in Kermanshah Province, west of Iran. Faecal samples were collected from domestic and stray dogs from 30 rural areas of Kermanshah province from August 2014 to April 2015 and were analyzed by formalin-ether sedimentation, sucrose otation technique and the modied Ziehl-Neelsen method. Out of 301 dogs examined, 230 (76.4%) were infected with at least one parasite. The incidence on the different types of intestinal parasitic species recovered from domestic and stray dogs are as follows: Toxocara leonina (20.8% and 27.6%), T. canis (7.5% and 9.4%), Taenia spp. (9.2% and 9.4%), hookworm spp. (18.3% and 33.7%), Capillaria spp. (0.8 and 1.7%), Dicrocoelium dendriticum (0.8% and 3.3%), Fasciola spp. (0.8% and 2.2%), Acanthocephal spp. (3.3% and 5.5%), Trichuris vulpis (0.8% and 1.7%), Dipylidium caninum (4.2% and 3.3%), Physaloptera spp. (6.7% and 6.6%), Cryptosporidium spp.(21.7% and 25.4%), Eimeria spp. (35.0% and 34.3%), Giardia spp. (6.7% and 12.7%), Cystoisospora spp. (7.5% and 5.5%), Blastocystis spp. (18.3% and 20.4%) and Sarcocystis spp. (6.7% and 7.2%), respectively. Signicant difference in infection rates was observed between domestic and stray dogs (P>0.05). Hookworm and Eimeria spp. were the most common intestinal helminth and protozoa detected with 83 (27.6%) out of 301 and 104 (34.6%), out of 301, respectively. There was no significant difference in prevalence and distribution of intestinal parasites between male and female dogs (P>0.05). The wide range of zoonotic parasites indicated that people residing in rural areas in Kermanshah province are at risk of exposure to these pathogens. In this respect, appropriate implementation of control programs by public health authorities and veterinarians should be taken into account.

20.
Trop Biomed ; 35(1): 91-99, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33601781

RESUMO

Echinococcus granulosus, the etiologic agent of echinococcosis, is one of the most important zoonotic helminthes worldwide. Knowledge of E. granulosus species and genotypes has important implications for epidemiology, control, and prevention of diseases as well as future vaccine and drug designs. There are many molecular methods developed to define genotypes of E. granulosus, among them high resolution melting (HRM) analysis, as a new approach, is a single step and closed tube method. It is appropriate for fast screening of large number of isolates. This technique is an accurate, user friendly, cost-effective, fast and simple method, which does not need post-PCR processes. Between March and lst august 2016, of 726 sheep examined in abattoirs in Razavi Khorasan province, Northeast Iran, 109 harboured cystic echincoccosis lesions (liver samples= 65 and lung samples= 44) which were collected for analysis. Total genomic DNA was extracted from each sample and amplified for the presence of polymorphism in the mitochondrial cox1 gene of Echinococcus granulosus using a high resolution melting curve (HRM) method. A total of 109 hydatid cyst samples analyzed by PCR high-resolution melting (qPCR-HRM) curve of the cox1 gene, all isolates were identified as G1 genotype (sheep strain). G1 is the predominant genotype in sheep in northeast of Iran. The high incidence of the G1 genotype (known to be the predominant E. granulosus genotype infecting humans globally) in sheep has considerable implications for hydatid disease control programs in this area.

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