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2.
Materials (Basel) ; 15(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36363352

RESUMO

Prior to the long-term utilization of solid oxide fuel cell (SOFC), one of the most remarkable electrochemical energy conversion devices, a variety of difficult experimental validation procedures is required, so it would be time-consuming and steep to predict the applicability of these devices in the future. For numerous years, extensive efforts have been made to develop mathematical models to predict the effects of various characteristics of solid oxide fuel cells (SOFCs) components on their performance (e.g., voltage). Taking advantage of the machine learning (ML) method, however, some issues caused by assumptions and calculation costs in mathematical modeling could be alleviated. This paper presents a machine learning approach to predict the anode-supported SOFCs performance as one of the most promising types of SOFCs based on architectural and operational variables. Accordingly, a dataset was collected from a study about the effects of cell parameters on the output voltage of a Ni-YSZ anode-supported cell. Convolutional machine learning models and multilayer perceptron neural networks were implemented to predict the current-voltage dependency. The resulting neural network model could properly predict, with more than 0.998 R2 score, a mean squared error of 9.6 × 10-5, and mean absolute error of 6 × 10-3 (V). Conventional models such as the Gaussian process as one of the most powerful models exhibits a prediction accuracy of 0.996 R2 score, 10-4 mean squared, and 6 × 10-3 (V) absolute error. The results showed that the built neural network could predict the effect of cell parameters on current-voltage dependency more accurately than previous mathematical and artificial neural network models. It is noteworthy that this procedure used in this study is general and can be easily applied to other materials datasets.

3.
J Parasit Dis ; 46(2): 502-510, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35692476

RESUMO

Zoonotic cutaneous leishmaniasis (ZCL) caused by Leishmania major is an important endemic disease and a major public health concern in Iran. Following an outbreak of leishmaniasis in 2013 in one of the important foci in Iran, the researchers were prompted to determine the underlying causes of the epidemic. Adult sand flies were collected using sticky traps and aspirating tubes and infection with Leishmania parasites was evaluated. Also, rodents were captured using Sherman live traps and stray dogs were hunted and were tested for the presence of leishmanial infection. Active case detection was also conducted and data related to each household were recorded using a researcher-designed form. Nested PCR and PCR-RLFP techniques were employed to determine Leishmania infection in the samples. Phlebotomus papatasi was the most dominant species among the 7 different species of sand flies collected in this study. Sergentomyia clydei, Sergentomyia theodori, and Sergentomyia grekovi were identified for the first time in the study area. 20% of collected Ph. papatasi species and one Meriones libycus were infected with Leishmania major. Stray dogs demonstrated no lesions on different parts of their body. The relative frequency of active lesions and scars on the dogs were respectively 5.49% and 1.23% in 2013 and 5.82% and 0.56% in 2014. The highest number of ZCL cases due to L. major was recorded in Ardestan city. Phlebotomus papatasi is the main vector and M. libycus seems to be the primary reservoir host of ZCL in the suburbs of this city. Furthermore, due to the low density of rodent reservoir hosts in the study area, we support the hypothesis that humans may have had a role in maintaining the parasite cycle in the population.

4.
Iran J Public Health ; 50(2): 350-359, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33747999

RESUMO

BACKGROUND: Leishmaniasis is an expanding neglected tropical disease in the world reporting from 98 countries including Iran. This study focused on eco-epidemiological determinants of the disease following a rapid and unexpected increase of leishmaniasis incidence in a strategic residential district in North-East of Isfahan County, Iran. METHODS: This study was accomplished from Apr 2012 to Jan 2014 in a strategic residential zone in North-East of Isfahan County, Esfahan, Iran. Monthly activity, parity, Leishmania infection and susceptibility tests, were determined on sand flies. Some portion of inhabitants and school children were surveyed to find active or passive cases of leishmaniasis and also wild rodents were collected to determine reservoir host. RESULTS: Totally 5223 sand flies belonging to Phlebotomus and Sergentomyia genus were collected and identified; Ph. papa-tasi was the dominant species and started to appear in May and disappeared in Oct. The majority of living dissected sand flies were unfed and parous. Ph. papatasi showed 4.6% Leishmania infection through direct examination and 39.54% by nested-PCR respectively. Phlebotomus papatasi was susceptible against deltametrin 0.05%. Totally 2149 people were surveyed and incidence and prevalence of zoonotic cutaneous leishmaniasis estimated as 45.39 and 314.40 per 1000 population. Rodents showed 73.91% and 80% Leishmania infection by direct examination and nested-PCR respectively. CONCLUSION: Cutaneous leishmaniasis due to L. major has been established in this area. Rodent control operation and personal protection are highly recommended to control the disease in this focus.

5.
J Arthropod Borne Dis ; 14(2): 134-143, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33365341

RESUMO

BACKGROUND: Esfahan Province is considered as one of the main focus of zoonotic cutaneous leishmaniasis (ZCL) in Iran. Recently, ZCL distribution is expanding through this province leading to report of new cases in non-endemic areas. In the current study epidemiological aspects of ZCL has been investigated in Naein County in Esfahan Province. METHODS: Adult sand flies were collected from beginning to the end of their seasonal activity. Rodents were caught by Sherman live traps once a month for one year. To active case detection, a hundred households in each selected village were visited in November and December 2016. Nested-PCR was employed to detect Leishmania parasite in the vector, reservoir and human. RESULTS: Totally 1562 sand flies including Phlebotomus sergenti, Phlebotomus papatasi, Sergentomyia sintoni and Sergentomyia mervinae were collected and identified. No Leishmania infection was detected in the collected sand flies. All of the 30 collected rodents were identified as Rhombomys opimus, and of these 3.3% and 26.7% were infected by Leishmania major using microscopic and molecular technique respectively. Totally, 914 individuals were investigated and the ulcer and scar rates of ZCL calculated to be at 1.1 and 15.3 per 1000 population, respectively. Molecular results confirmed L. major infection in human and reservoir samples. CONCLUSION: It is concluded that ZCL is established in the area in low endemicity, and it is extrapolated the disease will not be a serious increasing health problem in the near future in this region.

6.
J Arthropod Borne Dis ; 7(1): 1-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23785689

RESUMO

BACKGROUND: Sand flies of subgenus Adlerius has a wide geographical distribution in Iran and are mostly found in wild form in mountainous areas. They are always considered as probable vectors of visceral leishmaniasis. The objective of this study was to determine the Adlerius species and its composition in an endemic focus of zoonotic visceral leishmaniasis in northwest of the country. METHODS: Sand flies were collected from 6 different areas of Azarbaijan-e-Sharqi Province using sticky paper traps from August to September which is active season for sand flies in this area, in 2009. The flies were mounted and identified. The length of third antennal segments, ascoid, labrum, coxite, surstyle, style, aedeagus, genital filament, genital pump, width of style, and the end of aedeagus were measured and the number of costal hairs group was also counted as the morphological characters. RESULTS: A total of 30 adult sand flies, (26 males and 4 females) including Phlebotomus halepensis (46.8%), P. longiductus (13.3%), P. balcanicus (23.3%), P. comatus (3.3%), and Adlerius spp. (13.3%) belong to subgenus Adlerius were identified respectively in 6 counties. One P. comatus male was captured in front of a cave located in the hillside of a mountain covered with the vegetation in Varzeqan area. CONCLUSION: The presence of at least 5 species of the subgenus Adlerius in Azarbaijan-e-Sharqi Province, an endemic focus of zoonotic visceral leishmaniasis in Iran, shows that the risk of parasite transmission among man and reservoir animals is high during the active season of sand flies. P. comatus is a new record for Iran and needs to be added to the list of Iranian phlebotomines of subgenus Adlerius.

7.
Exp Parasitol ; 126(4): 552-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20566364

RESUMO

Many rodent species act as reservoir hosts of zoonotic cutaneous leishmaniasis in endemic areas. In the present study a simple and reliable assay based on nested PCR was developed for the detection and identification of Leishmania parasites from rodent skin samples. We designed Leishmania-specific primers that successfully amplified ITS regions of Leishmania major, Leishmania gerbilli and Leishmania turanica using nested PCR. Out of 95 field collected Rhombomys opimus, 21 were positive by microscopic examination and 48 by nested PCR. The percentage of gerbils infected with L. major, L. gerbilli and L. turanica was 3.2%, 1.1% and 27.4%, respectively. In 15.8% of the rodents, we found mixed natural infections by L. major and L. turanica, 1.1% by L. major and L. gerbilli, and 2.1% by the three species. We concluded that this method is simple and reliable for detecting and identifying Leishmania species circulating in rodent populations.


Assuntos
Reservatórios de Doenças/parasitologia , Gerbillinae/parasitologia , Leishmania/isolamento & purificação , Leishmaniose Cutânea/veterinária , Doenças dos Roedores/parasitologia , Pele/parasitologia , Animais , Primers do DNA/química , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Eletroforese em Gel de Ágar/veterinária , Irã (Geográfico)/epidemiologia , Leishmania/classificação , Leishmania/genética , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/parasitologia , Reação em Cadeia da Polimerase/veterinária , Doenças dos Roedores/epidemiologia
8.
Exp Parasitol ; 124(2): 209-13, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19769969

RESUMO

Accurate morphological differentiation between the liver fluke species Fasciola hepatica and Fasciola gigantica is difficult. We evaluated PCR-restriction enzyme profiles of internal transcribed spacer 1 (ITS1) that could aid in their identification. Fifty F. hepatica and 30 F. gigantica specimens were collected from different hosts in three provinces of Iran. For DNA extraction, we crushed fragments of the worms between two glass slides as a new method to break down the cells. DNA from the crushed materials was then extracted with a conventional phenol-chloroform method and with the newly developed technique, commercial FTA cards. A primer pair was selected to amplify a 463-bp region of the ITS1 sequence. After sequencing 14 samples and in silico analysis, cutting sites of all known enzymes were predicted and TasI was selected as the enzyme that yielded the most informative profile. Crushing produced enough DNA for PCR amplification with both the phenol-chloroform and commercial FTA card method. The DNA extracted from all samples was successfully amplified and yielded a single sharp band of the expected size. Digestion of PCR products with TasI allowed us to distinguish the two species. In all samples, molecular identification was consistent with morphological identification. Our PCR-restriction enzyme profile is a simple, rapid and reliable method for differentiating F. hepatica and F. gigantica, and can be used for diagnostic and epidemiological purposes.


Assuntos
DNA de Helmintos/isolamento & purificação , Fasciola hepatica/isolamento & purificação , Fasciola/isolamento & purificação , Fasciolíase/parasitologia , Reação em Cadeia da Polimerase/métodos , Matadouros , Animais , Sequência de Bases , Búfalos , Bovinos , Primers do DNA , Enzimas de Restrição do DNA , DNA de Helmintos/química , Diagnóstico Diferencial , Eletroforese em Gel de Ágar , Fasciola/classificação , Fasciola/genética , Fasciola hepatica/classificação , Fasciola hepatica/genética , Fasciolíase/diagnóstico , Cabras , Irã (Geográfico) , Fígado/parasitologia , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Mapeamento por Restrição , Alinhamento de Sequência , Ovinos
9.
Ann Saudi Med ; 27(1): 6-12, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17277492

RESUMO

BACKGROUND: Anthroponotic cutaneous leishmaniasis (ACL) has long been a significant public health problem in northeastern Iran. The objective of this study was to determine the efficacy of deltamethrin-impregnated vs. nonimpregnated bed nets (NIBs) and curtains (NICs) in ACL control. PATIENTS: Deltamethrin-impregnated bed nets (IBs) and curtains (ICs) with 25 mg ai/m2 were distributed among 160 households in one district and NIBs and NICs were distributed among the same number of households in another district. A third district with a similar numbers of households served as a control. Health education mes- sages were disseminated to ensure the populationâs complicance with the proper use of bed nets and curtains. Sticky paper traps were used to assess the effect of insecticide-impregnated bed nets and curtains on the density of Phlebotomus sergenti. Deltamethrin susceptibility and also bioassay tests were carried out on the species by WHO standard method. Case findings were done by house-to-house visits once a season and all the inhabitants of the selected households in each district were examined. RESULTS: IBs and ICs provided good protection against sandfly bites and reduced the transmission of ACL in the intervention district, while NIBs and NICs provided no protection. There was no significant difference in monthly density of P. sergenti indoors and outdoors among the districts (P>0.05). This species was susceptible to delta- methrin in the field population in the area. Bioassays confirmed that the nets treated with deltamethrin remained effective for more than 3 months. CONCLUSION: Personal protection is an effective and sustainable means of preventing and controlling ACL and can reduce dependence on insecticides. We encourage the use of IBs and ICs to control ACL in other high-risk areas of Iran and Afghanistan during the active season of sandflies.


Assuntos
Roupas de Cama, Mesa e Banho , Doenças Endêmicas , Inseticidas , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/prevenção & controle , Phlebotomus , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Irã (Geográfico)/epidemiologia , Masculino , Nitrilas , Piretrinas , Saúde da População Rural , Zoonoses
10.
Ann Saudi Med ; 25(4): 309-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16212124

RESUMO

BACKGROUND: Zoonotic cutaneous leishmaniasis (ZCL) is a serious and increasing public health problem in many rural areas of Iran. Previous studies showed that rodent control operations are effective in destroying rodents and reducing the incidence of ZCL on a small scale and in special circumstances. The objective of this study was to determine suitable timing for rodent control operations in reducing the incidence of ZCL in an endemic area in Badrood, Iran. METHODS: We conducted rodent control operations by baiting rodent holes using zinc phosphide once a month in May, June, July and September in 1997 within a 500-meter circle of houses in the intervention area. From 1999 to 2002, the numbers of active rodent holes were counted in May and October in the intervention and control areas. When the numbers of rodent holes increased to 30% or more of the number before the first baiting in May 1997, holes in the intervention area were baited again with zinc phosphide in the intervention area; no baiting was done in the control village. Case findings were done by house-to-house visits once every season during 2000 to 2002. RESULTS: Changes in the number of rodent holes over time in the intervention and control villages were statistically significant (P<0.000001). There were also significant differences in the incidence of ZCL between the intervention and control villages (P<0.005) during 2000 to 2002. The incidence of ZCLwas unchanged in the years 2000 and 2001, but increased in one village in 2002 after an increase in the number of rodent holes. CONCLUSION: We suggest that rodent control operations using zinc phosphide be done within a 500-meter circle of houses once every two years before the beginning of the active season of sandflies, which begins in late April.


Assuntos
Leishmaniose Cutânea/prevenção & controle , Controle de Roedores , Zoonoses , Animais , Humanos , Incidência , Irã (Geográfico)/epidemiologia , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/microbiologia , Saúde da População Rural
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