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1.
Comp Immunol Microbiol Infect Dis ; 109: 102184, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38691874

RESUMO

BACKGROUND: Toxoplasma gondii is an apicomplexan protozoan parasite that infects one-third of the population of the world, including humans, animals, birds, and other vertebrates. The present investigation is the first molecular attempt in the Malakand Division of Pakistan to determine the epidemiology and phylogenetic study of Toxoplasma gondii infecting small ruminants. METHODOLOGY: A total of (N = 450) blood samples of sheep were randomly collected during the study period (December 2020 to November 2021), and DNA detection was done using PCR by amplifying ITS-1 genes. SPSS.20 and MEGA-11 software were used for statistical significance and phylogenetic analysis. RESULTS: The overall prevalence of T. gondii infection among sheep was 14.44 % (65/450). A high infection rate was found in more than five-year-olds at 18.33 % (11/60). Sequencing and BLAST analysis of PCR-positive samples confirmed the presence of T. gondii. Randomly, three isolates were sequenced and submitted to GenBank under accession numbers (PP028089-PP028091), respectively. The BLAST analysis of the obtained sequences based on the ITS-1 gene showed 99 % similarities with reported genotypes found in goats of Malakand, Pakistan (PP028089) and dogs of Brazil (MF766454). The study concludes that T. gondii is notably prevalent among the sheep population in the region, emphasizing the significant role of risk factors in disease transmission across animals and potentially to humans. Further research, zoonotic potential analysis, and targeted control measures are warranted to address and manage this parasitic infection effectively.


Assuntos
DNA de Protozoário , Filogenia , Doenças dos Ovinos , Toxoplasma , Toxoplasmose Animal , Animais , Toxoplasma/genética , Toxoplasma/isolamento & purificação , Toxoplasma/classificação , Paquistão/epidemiologia , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologia , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/parasitologia , Prevalência , DNA de Protozoário/genética , Genótipo , Reação em Cadeia da Polimerase
2.
Anal Methods ; 16(8): 1261-1271, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38323472

RESUMO

A fluorescence probe based on iron oxide quantum dots (IO-QDs) was synthesized using the hydrothermal method for the determination of tetracycline (TCy) and ciprofloxacin (CPx) in aqueous solution. The IO-QDs were characterized using high-resolution transmission electron microscopy (HR-TEM), powder X-ray diffraction (P-XRD), vibrating sample magnetometry (VSM), and Fourier-transform infrared spectroscopy (FTIR). The as-prepared IO-QDs are fluorescent, stable, and with a fluorescence quantum yield (QY) of 9.8 ± 0.12%. The fluorescence of IO-QDs was observed to be quenched and enhanced in the presence of TCy and CPx, respectively. The fluorescence intensity ratio shows linearity at concentrations from 1-100 µM and 5-100 µM for TCy and CPx, respectively; the detection limit for TCy and CPx was estimated to be 0.71 µM and 1.56 µM, respectively. The proposed method was also successfully utilized in the spiked samples of drinking water and honey with good recoveries. The method offered convenience, rapid detection, high sensitivity, selectivity, and cost-efficient alternative options for the determination of TCy and CPx in real samples.


Assuntos
Antibacterianos , Compostos Férricos , Pontos Quânticos , Ciprofloxacina , Pontos Quânticos/química , Tetraciclina
3.
Sci Rep ; 14(1): 12791, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38834768

RESUMO

In the conventional finite control set model predictive torque control, the cost function consists of different control objectives with varying units of measurements. Due to presence of diverse variables in cost function, weighting factors are used to set the relative importance of these objectives. However, selection of these weighting factors in predictive control of electric drives and power converters still remains an open research challenge. Improper selection of weighting factors can lead to deterioration of the controller performance. This work proposes a novel weighting factor tuning method based on the Multi-Criteria-Decision-Making (MCDM) technique called the Entropy method. This technique has several advantages for multi-objective problem optimization. It provides a quantitive approach and incorporates uncertainties and adaptability to assess the relative importance of different criteria or objectives. This technique performs the online tuning of the weighting factor by forming a data set of the control objectives, i.e., electromagnetic torque and stator flux magnitude. After obtaining the error set of control variables, the objective matrix is normalized, and the entropy technique is applied to design the corresponding weights. An experimental setup based on the dSpace dS1104 controller is used to validate the effectiveness of the proposed method for a two-level, three-phase voltage source inverter (2L-3P) fed induction motor drive. The dynamic response of the proposed technique is compared with the previously proposed MCDM-based weighting factor tuning technique and conventional MPTC. The results reveal that the proposed method provides an improved dynamic response of the drive under changing operating conditions with a reduction of 28% in computational burden and 38% in total harmonic distortion, respectively.

4.
ACS Omega ; 9(16): 18148-18159, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680354

RESUMO

Herein, we present a detailed comparative study of the structural, elastic, electronic, and magnetic properties of a series of new halide perovskite AgCrX3 (X: F, Cl, Br, I) crystal structures using density functional theory, mean-field theory (MFT), and quantum Monte Carlo (MC) simulations. As demonstrated by the negative formation energy and Born-Huang stability criteria, the suggested perovskite compounds show potential stability in the cubic crystal structure. The materials are ductile because the Pugh's ratio is greater than 1.75, and the Cauchy pressure (C12-C44) is positive. The ground state magnetic moments of the compound were calculated as 3.70, 3.91, 3.92, and 3.91 µB for AgCrF3, AgCrCl3, AgCrBr3, and AgCrI3, respectively. The GGA + SOC computed spin-polarized electronic structures reveal ferromagnetism and confirm the metallic character in all of these compounds under consideration. These characteristics are robust under a ±3% strained lattice constant. Using relativistic pseudopotentials, the total energy is calculated, which yields that the single ion anisotropy is 0.004 meV and the z-axis is the hard-axis in the series of AgCrX3 (X: F, Cl, Br, and I) compounds. Further, to explore room-temperature intrinsic ferromagnetism, we considered ferromagnetic and antiferromagnetic interactions of the magnetic ions in the compounds by considering a supercell with 2 × 2 × 2 dimensions. The transition temperature is estimated by two models, namely, MFT and MC simulations. The calculated Curie temperatures using MC simulations are 518.35, 624.30, 517.94, and 497.28 K, with ±5% error for AgCrF3, AgCrCl3, AgCrBr3, and AgCrI3 compounds, respectively. Our results suggest that halide perovskite AgCrX3 compounds are promising materials for spintronic nanodevices at room temperature and provide new recommendations. For the first time, we report results for novel halide perovskite compounds based on Ag and Cr atoms.

5.
Sci Rep ; 14(1): 3962, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368469

RESUMO

This work presents an energy management scheme (EMS) based on a rule-based grasshopper optimization algorithm (RB-GOA) for a solar-powered battery-ultracapacitor hybrid system. The main objective is to efficiently meet pulsed load (PL) demands and extract maximum energy from the photovoltaic (PV) array. The proposed approach establishes a simple IF-THEN set of rules to define the search space, including PV, battery bank (BB), and ultracapacitor (UC) constraints. GOA then dynamically allocates power shares among PV, BB, and UC to meet PL demand based on these rules and search space. A comprehensive study is conducted to evaluate and compare the performance of the proposed technique with other well-known swarm intelligence techniques (SITs) such as the cuckoo search algorithm (CSA), gray wolf optimization (GWO), and salp swarm algorithm (SSA). Evaluation is carried out for various cases, including PV alone without any energy storage device, variable PV with a constant load, variable PV with PL cases, and PV with maximum power point tracking (MPPT). Comparative analysis shows that the proposed technique outperforms the other SITs in terms of reducing power surges caused by PV power or load transition, oscillation mitigation, and MPP tracking. Specifically, for the variable PV with constant load case, it reduces the power surge by 26%, 22%, and 8% compared to CSA, GWO, and SSA, respectively. It also mitigates oscillations twice as fast as CSA and GWO and more than three times as fast as SSA. Moreover, it reduces the power surge by 9 times compared to CSA and GWO and by 6 times compared to SSA in variable PV with the PL case. Furthermore, its MPP tracking speed is approximately 29% to 61% faster than its counterparts, regardless of weather conditions. The results demonstrate that the proposed EMS is superior to other SITs in keeping a stable output across PL demand, reducing power surges, and minimizing oscillations while maximizing the usage of PV energy.

6.
Heliyon ; 10(13): e33443, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39035548

RESUMO

In this study, band structure and optical properties of Manganese (Mn) doped ZnO are investigated adopting first-principles study calculations. It is observed that, by addition of Mn in ZnO crystal, the electrical properties like conductivity and dielectric function of material have been improved. The elastic constants for the elements are also calculated which shows that the element is stable after addition of dopant. The computational study is done on CASTEP and Material Studio. The ZnO system is simulated and atoms of Mn has been added replacing Zn atoms. The properties that studied are band structure and optics including conductivity, reflectivity, dielectric function, absorption and refractive index. Furthermore, this study also includes calculation of Elastic constants, XRD Spectra, Phonon dispersion and Temperature profile of doped ZnO systems. The computational study produced promising results and experimental approach can be adopted to reinforce the outcomes of this study.

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