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1.
RSC Adv ; 13(6): 3552-3560, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36756589

RESUMO

In the present analysis, we study the energy transference through engine oil-based Prandtl-Eyring nanofluid flow through a heated stretching surface. The nanofluid is prepared by adding copper (Cu) and titanium dioxide (TiO2) nanoparticles (NPs) to the base fluid engine oil. The flow mechanism and thermal transmission are observed by exposing the nanofluid flow through the heated slippery surface. The influences of permeable surface, radiative flux and heat absorption/generation are also elaborated in this study. The flow of nanofluids has been designed using a PDEs system, which are then transformed into a set of ODEs via resemblance modification. The numerical technique "shooting method" is used to solve the acquired nonlinear set of non - dimensional ODEs. The results are physically exemplified through tables and plots. It has been detected that the accumulation of nanomaterials in the engine oil, reduces the skin friction while accelerating the energy transfer rate. The velocity field significantly decelerates with the encouragement of the porosity factor, and volume fraction of NPs. However, the temperature profile significantly escalates with the encouragement of the porosity factor, and volume fraction of NPs.

2.
Sci Rep ; 12(1): 21126, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36477598

RESUMO

The attention of the current study is on the flow of a non-Newtonian incompressible Cu-Water nanofluid flow. The water is assumed as base fluid, while copper is used as nanoparticles. The Ree-Eyring prototype describes the performance of non-Newtonian nanofluids. There is a conical gap that nanofluid flow fills among the plane disc and the cone's stationary/rotational porous faces. Additionally taken into account are heat, mass transfer, and entropy production. The given mathematical model is unique due to the effects of a vertically applied Hall Effect, Ohmic dissipation, viscous dissipation, and chemical processes. The Ree-Eyring fluid constitutive equations, as well as the cylindrical coordinates, have been interpreted. The model equations for motion, heat, and concentration can be changed in the collection of non-linear ODEs by employing the applicable similarity transform. This method allocates a couple of nonlinear ODEs relating to velocity, temperature, and concentration distributions. The shooting scheme (bvp4c technique) is used to solve these equations numerically. Statistical analysis like probable error, correlation, and regression are exploited. The probable error is estimated to compute the consistency of the calculated correlation features. The theoretical data is analyzed in both graphical and tabular forms. The modeled parameters like, magnetic number, porosity parameter, Eckert number, chemical reaction parameter, Brownian motion parameter, thermophoretic parameter, Schmidt number, Hall recent parameter, radiation parameter, and volume fraction are discussed in details graphically and theoretically. The outcomes indicate that the velocity components are greater for greater values of nanoparticle volume fraction and Weissenberg number, whereas for enormous values of magnetic and porosity parameters, the velocity components fall.

3.
ACS Omega ; 7(41): 36611-36622, 2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36278065

RESUMO

The purpose of this study is to evaluate the augmentation of thermal energy transfer in trihybrid Ellis nanofluid flow in the occurrence of magnetic dipole passes over a vertical surface. The ternary hybrid nanofluid is prepared by the dispersion of ternary nanoparticles (Al2O3, SiO2, and TiO2) in the Carreau Yasuda fluid. The velocity and heat transportation has been examined in the existence of the Darcy Forchhemier influence and heat source/sink. The phenomena of fluid flow have been mathematically designed for energy and fluid velocity in the form of a nonlinear partial differential equation (PDE)-based system. The system of PDEs is further refined to the set of ordinary differential equations via suitable similarity substitutions. The acquired dimensionless equations are numerically solved with the help of the HAM. It has been noticed that the energy contour is enhanced versus the variation of viscous dissipation and heat generation. A significant contribution of a magnetic dipole is observed to elevate the production of the thermal energy field, and an opposite trend is noticed versus the flow profile. The accumulation of Al2O3, SiO2, and TiO2 nanomaterials in the base fluid "engine oil" improves the velocity and energy profiles.

4.
ACS Omega ; 7(31): 27436-27449, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35967050

RESUMO

Stratification is used in a wide range of energy storage fields, including solar thermal energy systems. This paper investigates entropy optimization and the effects of heat production, magnetic field, and various fluid parameters on the flow of second-grade fluid through unstratified and stably stratified paraboloids of revolution. In the heat transfer equation, stratification, linear thermal radiation, and Joule dissipation have all been explored. The similarity transformation is used to convert the governing PDEs into nonlinear ODEs. The HAM (homotopy analysis method) is used to solve dimensionless nonlinear ODEs. The impact of significant elements on various profiles is exposed and explored. Graphical results are used to examine the influence of the velocity profile, temperature, concentration, and entropy formation rate using tables to indicate the characteristics of skin friction, Nusselt number, and Sherwood number for numerous parameters. It is noticed that the velocity is enhanced by raising the stratification parameter, while the opposite behavior is observed for temperature distribution. The concentration profile declined as the solute stratification parameter was enhanced. For both the unstratified and stratified regions, incremental values of the Brinkman number and magnetic parameter depict augmentation in entropy production, while entropy production drops for a large value of the temperature ratio parameter.

5.
Micromachines (Basel) ; 13(8)2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-36014225

RESUMO

Nanofluids are extremely useful to investigators due to their greater heat transfer rates, which have significant applications in multiple industries. The primary objective of this article is to look into the effect of viscous dissipation in Sisko nano liquid flow with gold Au nanoparticles on a porous stenosis artery. Heat transfer properties were explored. Blood was utilized as a base fluid for nanoparticles. To renovate the governing nonlinear PDEs into nonlinear ODEs, appropriate transformations were used. The bvp4c-based shooting method, via MATLAB, was used to determine the numerical results of the nonlinear ODEs. Furthermore, flow forecasts for each physical quantity were explored. To demonstrate the physical influences of flow constraints versus presumed flow fields, physical explanations were used. The findings demonstrated that the velocity contour improved as the volume fraction, curvature, power law index, and material parameter upsurged. For the Prandtl number, the volume fraction of nanoparticles, the index of the power law, and the temperature profile of the nanofluid declined. Furthermore, the drag force and transfer of the heat were also investigated as explanations for influences on blood flow. Further, the Nusselt number reduced and the drag force enhanced as the curvature parameter values increased. The modeling and numerical solutions play an impressive role in predicting the cause of atherosclerosis.

6.
Front Genet ; 12: 751552, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34868223

RESUMO

Background: Understanding the genetic diversity of Plasmodium species through polymorphic studies can assist in designing more effective control strategies of malaria like new drug formulation and development of a vaccine. Pakistan is moderate endemic for Plasmodium falciparum, but little is known about the genetic diversity of this parasite. This study aimed to investigate the molecular diversity of P. falciparum based on msp-1 and msp-2 genes in the malaria-endemic regions of Khyber Pakhtunkhwa, Pakistan. Methods: A total of 199/723 blood samples, tested positive by microscopy for falciparum malaria, were collected from four districts (Dera Ismail Khan, Karak, Mardan, and Peshawar) of Khyber Pakhtunkhwa. Nested PCR amplification technique was employed to target block 2 of msp-1 and the central domain of msp-2 genes, including their respective allelic families K1, MAD20, RO33, FC27, and 3D7/IC, and to detect the extent of genetic diversity of P. falciparum clinical isolates. Results: Among the 199 microscopy-positive P. falciparum samples, a total of 192 were confirmed using PCR. Ninety-seven amplicons were observed for msp-1 and 95 for msp-2. A total of 33 genotypes, 17 for msp-1 (eight K1, six MAD20, and three RO33) and 16 for msp-2 (nine FC27 and seven 3D7/IC), were identified. The specific allelic frequency of the K1 family was higher (44.3%) than that of MAD20 (33.0%) and RO33 (23.0%) for msp-1, while the FC27 allelic family was dominant (60.0%) compared with 3D7/IC (40.0%) for msp-2. No polyclonal infection was observed in msp-1 and msp-2. The expected heterozygosity was 0.98 and 0.97 for msp-1 and msp-2, respectively. Conclusion: It was concluded that the P. falciparum populations are highly polymorphic, and diverse allelic variants of msp-1 and msp-2 are present in Khyber Pakhtunkhwa, Pakistan.

7.
Sci Rep ; 11(1): 18386, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526593

RESUMO

The entropy generation for a reactive Williamson nanofluid flow past a vertical Riga system is the subject of this article. The effects of MHD, thermophoresis, nonlinear heat radiation and varying heat conductivity are modeled into the heat equation in the established model. Suitable similarity transformations are examined to bring down the partial differential equations into ordinary differential equations. The Homotopy analysis approach is used to solve the dimensionless transport equations analytically. The graphic information of the various parameters that emerged from the model is effectively collected and deliberated. The temperature field expands with thermophoresis, Brownian motion and temperature ratio parameters as the modified Hartmann number forces an increase in velocity, according to the findings of this analysis. With the increase in the fluid material terms, the entropy generation and Bejan number increase. Riga plate has numerous applications in improving the thermo-physics features of a fluid, the value of magnetic field embraces an important role in fluid mechanics. An external electric field can be used to control flow in weak electrically conductive fluids. The Riga plate is one of the devices used in this regard. It's a device that creates electromagnetic fields. They produce the Lorentz force which is a force that directs fluid flow. The authors have discussed the entropy optimization for a reactive Williamson nanofluid flow past a vertical Riga plate is addressed. This is the first investigation on mass and heat transfer flow that the authors are aware of, and no similar work has yet been published in the literature. A thorough mathematical examination is also required to demonstrate the model's regularity. The authors believe that the results acquired are novel and have not been plagiarized from any other sources.

8.
PLoS One ; 16(8): e0255138, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34351948

RESUMO

BACKGROUND: In tropical and subtropical countries, tick infestation causes major public health problems and considerable financial losses to the livestock industry. This study was aimed to assess the species composition of richness and analyze the phylogeny of Rhipicephalus microplus in the District Bannu of Khyber Pakhtunkhwa, Pakistan. METHODS: Collected ticks were identified morphologically and DNA extracted from R. microplus was amplified and subjected to sequencing. RESULTS: A total of 3,600 animals were examined among them 1,494 animals were found to be infested with ticks, including 669 cows, 476 buffaloes, 163 goats, and 186 sheep (p = 0.001). Tick infestation was significantly high (43.58%) in animals of age group (<1 year) (p-value = 0.027). Female animals were more (44.05%) infested with ticks than males (34.43%) (p = 0.001). The intensity of infestation was significantly higher in summer (77.49%) (p = 0.001). A total of 5,557 ticks were collected comprising three genera and six species. R. microplus was predominantly prevalent (n = 1,474; 26.52%), followed by Rhipicephalus annulatus (n = 1,215; 21.86%), Hyalomma anatolicum (n = 1,139; 20.49%), Hyalomma marginatum (n = 1,086; 19.54%), and Rhipicephalus turanicus (n = 761; 13.69%), while the least common was Haemaphysalis aciculifer (n = 80; 1.43%) (p = 0.001). Morphologically identified R. microplus species were also analyzed genetically by using two genetic markers 16S ribosomal RNA (16S rRNA) and internal transcribed spacer 2 (ITS2) genes. The phylogenetic study revealed that R. microplus is genetically diversified and clustered in clade B with R. microplus species from China, India, and Pakistan. CONCLUSION: Ticks infestation was significantly correlated with various factors including age, sex, season, and animal type. R. microplus genetically resembled species reported from India and China. However, major knowledge gaps concerning various species of ticks exist and many areas are still unexplored in Pakistan. Therefore, it is necessary to explore the epidemiological and molecular aspects of various tick species in other regions of southern Khyber Pakhtunkhwa.


Assuntos
Animais Domésticos/parasitologia , Parasitos/genética , Rhipicephalus/genética , Inquéritos e Questionários , Animais , Estudos Transversais , DNA Intergênico/genética , Geografia , Paquistão , Filogenia , RNA Ribossômico 16S/genética , Estações do Ano , Especificidade da Espécie
9.
Front Pharmacol ; 12: 644027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34040520

RESUMO

Background: Haemonchus contortus is an important pathogenic nematode parasite and major economic constraint of small ruminants in tropics and subtropics regions. This review is an attempt to systematically address the; (a) efficacy of different plants against H. contortus by in vitro and in vivo proof; (b) toxicology, mechanism of action, and active phyto-compounds involve in anti-haemonchiasis activity; (c) and comparative analysis of plant species evaluated both in vitro and in vivo. Methods: Online databases (Google Scholar, PubMed, Scopus, and ScienceDirect) were searched and published research articles (1980-2020) were gathered and reviewed. Results: A total of 187 plant species were reported belonging to 59 families and 145 genera with Asteraceae and Fabaceae being frequently used. Out of the total plant species, 171 species were found to be evaluated in vitro and only 40 species in vivo. Twenty-four species were commonly evaluated for in vitro and in vivo anti-haemonchiasis activity. Among the reported assays, egg hatching test (EHT) and fecal egg count reduction (FECR) were the most widely used assays in vitro and in vivo, respectively. Moreover, sheep were the frequently used experimental model in vivo. After comparative analysis, Lachesiodendron viridiflorum, Corymbia citriodora, Calotropis procera, and Artemisia herba-alba were found highly effective both in vitro and in vivo. L. viridiflorum inhibited enzymatic activities and metabolic processes of the parasite and was found to be safe without toxic effects. C. citriodora was moderately toxic in vivo, however, the plant extract produced promising nematicidal effects by causing muscular disorganization and changes in the mitochondrial profile. Additionally, C. procera and A. herba -alba despite of their high anti-haemonchiasis activity were found to be highly toxic at the tested concentrations. C. procera caused perforation and tegumental disorganization along with adult worm paralysis. Nineteen compounds were reported, among which anethole and carvone completely inhibited egg hatching in vitro and significantly reduced fecal egg count, decreased male length, and reproductive capacity of female in vivo. Conclusion: This review summarized different medicinal plants owing to nematicidal activities against H. contortus eggs, larvae, and adult worms. Plants like L. viridiflorum, C. citriodora, C. procera, and A. herba-alba, while compounds anethole and carvone having promising nematicidal activities and could be an alternative source for developing novel drugs after further investigation.

10.
BMC Vet Res ; 17(1): 139, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794898

RESUMO

BACKGROUND: Cystic echinococcosis (CE) is one of the principal causes of economic loss to the livestock industry because of its morbidity and mortality of food-producing animals and condemnation of important visceral organs. Pakistan being an agricultural country having an extensive livestock sector, is mostly practiced by poor people, which has a fundamental role in the economy. The present study was aimed to conduct a cross-sectional survey and PCR based confirmation of Echinococcus granulosus in sheep, goats, cows, and buffaloes from southern regions (three districts: Lakki Marwat, Bannu, and Karak) of Khyber Pakhtunkhwa, Pakistan. During the study, a total of 2833 animals were examined randomly including; sheep (n = 529), goats (n = 428), cows (n = 1693), and buffaloes (n = 183). Hydatid cysts were collected and examined for the presence of protoscoleces using microscopy. Detection of DNA was performed by using PCR and two mitochondrial genetic markers namely; NAD-1 and COX-1 were amplified. RESULTS: The overall prevalence of CE was found to be (9%) among the examined animals. The hydatid cyst infection was highly prevalent in buffaloes (12%), followed by sheep (10%), cows (9%), and goats (5.1%). Cystic echinococcosis was more prevalent (10%; 96/992) in district Lakki Marwat followed by district Bannu (9%; 112/1246) and Karak (7%; 39/595). Female animals were more likely to be infected with CE (11.6%) than male animals (5.3%) (p = 0.001). Similarly, the infection was higher in the older group of animals as compared to younger (p = 0.001). Mostly (52.2%; n = 129) of hydatid cysts were found in the liver, while (64.4%; n = 159) cysts of the infected animals were infertile. PCR based identification confirmed the presence of E. granulosus sensu stricto (s.s) in the study area. CONCLUSION: Cystic echinococcosis was found to be highly prevalent in southern regions of Khyber Pakhtunkhwa and could be a potential threat to human health. Moreover, molecular sequencing and phylogenetic analyses should be carried out in future to identify the prevailing genotype (s) of E. granulosus s.s.


Assuntos
Doenças dos Animais/epidemiologia , Equinococose/veterinária , Echinococcus granulosus/isolamento & purificação , Doenças dos Animais/parasitologia , Animais , Búfalos , Bovinos , Estudos Transversais , Equinococose/epidemiologia , Echinococcus granulosus/genética , Feminino , Cabras , Masculino , Paquistão/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Prevalência , Ovinos , Zoonoses/epidemiologia
11.
PLoS One ; 15(10): e0240456, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33048959

RESUMO

Cystic echinococcosis (CE) is a zoonotic helminthiasis caused by different species of the genus Echinococcus, and is a major economic and public health concern worldwide. Synthetic anthelmintics are most commonly used to control CE, however, prolonged use of these drugs may result in many adverse effects. This study aims to discuss the in vitro/in vivo scolicidal efficacy of different medicinal plants and their components used against Echinococcus granulosus. Google Scholar, ScienceDirect, PubMed and Scopus were used to retrieve the published literature from 2000-2020. A total of 62 published articles met the eligibility criteria and were reviewed. A total of 52 plant species belonging to 22 families have been reported to be evaluated as scolicidal agents against E. granulosus worldwide. Most extensively used medicinal plants against E. granulosus belong to the family Lamiaceae (25.0%) followed by Apiaceae (11.3%). Among various plant parts, leaves (36.0%) were most commonly used. Essential oils of Zataria multiflora and Ferula asafetida at a concentration of 0.02, and 0.06 mg/ml showed 100% in vitro scolicidal activity after 10 min post application, respectively. Z. multiflora also depicted high in vivo efficacy by decreasing weight and size while also causing extensive damage to the germinal layer of the cysts. Plant-based compounds like berberine, thymol, and thymoquinone have shown high efficacy against E. granulosus. These plant species and compounds could be potentially used for the development of an effective drug against E. granulosus, if further investigated for in vivo efficacy, toxicity, and mechanism of drug action in future research.


Assuntos
Anti-Helmínticos/uso terapêutico , Equinococose/tratamento farmacológico , Echinococcus granulosus/efeitos dos fármacos , Plantas Medicinais/metabolismo , Animais , Equinococose/parasitologia
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