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1.
J Mol Graph Model ; 131: 108808, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38852428

RESUMO

Hydrogen energy has attracted a lot of interest from researchers as a sustainable and renewable energy source, but there are some technical challenges related to its storage. Hydride materials demonstrate the ability to store hydrogen adequately and safely. In the current study, we have investigated the structural and optoelectronic properties of the XCuH3 (where X = Li, Na and K) perovskite-type hydride using LDA and GGA formalisms for hydrogen storage application. Electronic properties such as band structure, density of states reveal the metallic character of the studied XCuH3 hydrides. Various optical parameters such as the complex dielectric function, refractive index, extinction coefficient, absorption coefficient, reflectivity, optical conductivity, energy loss function, and joint density of states have been computed and compared. The gravimetric hydrogen storage capacity for LiCuH3, NaCuH3 and KCuH3 are found to be 4.11, 3.37 and 2.86 wt%, respectively. The computed values of the gravimetric ratio manifest that XCuH3 hydrides are potential candidates for hydrogen storage applications. These calculations are made for the first time for XCuH3 hydrides and will be inspirational in the future for comparison and for hydrogen storage purposes.


Assuntos
Compostos de Cálcio , Hidrogênio , Óxidos , Titânio , Hidrogênio/química , Compostos de Cálcio/química , Titânio/química , Óxidos/química , Sódio/química , Lítio/química , Potássio/química , Modelos Moleculares
2.
Environ Sci Pollut Res Int ; 31(20): 29033-29047, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38564131

RESUMO

The primary goal of this research is to look into the impact of digital campaigns for environmental and economic incentives on environmental performance, with indoor and outdoor activities of households taken as mediating variables. PLS-SEM was used to evaluate and quantify the novel and complex model to meet the study's goals. Furthermore, data were gathered from 1542 Pakistani households using convenient sampling techniques. The study's findings show that digital campaigns and economic incentives significantly increase household's participation in indoor and outdoor activities, which improves environmental performance. This study contributes to the literature on environmental performance by examining digital campaigns and economic incentives as resilient influencers. Furthermore, this study assists authorities in developing an effective and efficient policy that promotes environmental savaging information while providing economic incentives to encourage the activities. At the same time, it emphasizes environmental concerns and how they can be addressed.


Assuntos
Características da Família , Motivação , Humanos , Paquistão , Meio Ambiente
3.
Environ Monit Assess ; 196(5): 458, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635016

RESUMO

The poultry industry is a significant source of animal protein, vitamins, and minerals, particularly through the consumption of chicken meat. In order to conduct the study, 100 samples of liver, chicken feed, and drinking water were collected in nearby areas of Lahore. The investigation aims to detect the presence of specific heavy metals in the collected samples. For this purpose, atomic absorption spectroscopy (AAS) was used to detect heavy metals after proper preparation of the samples. The experimentally observed data were analyzed through a novel statistical approach known as neutrosophic statistics. It was observed that copper (Cu), zinc (Zn), and cadmium (Cd) were the most prominent metals detected with contamination above the safe limits (for chicken drinking water (Zn = 23.09±13.67 mg/L, Cu = 3.84±3.04 mg/L, Cd = 0.805±0.645 mg/L, Pb = 0.275±0.095 mg/L, As = 0.982±0.978 mg/L), for chicken feed (Zn = 2.705±0.715 mg/kg, Cu = 1.85±0.53 mg/kg, Cd = 3.065±1.185 mg/kg, Pb = 0.215±0.175 mg/kg, As = 0.68±0.22 mg/kg), and chicken's liver (Zn = 3.93±0.66 mg/kg, Cu = 1.2±0.52 mg/kg, Cd = 0.07±0.05 mg/kg, Pb = 0.805±0.775 mg/kg, As = 1.05±0.8 mg/kg)). Similarly, the statistical analysis leads that the findings emphasize the importance of monitoring and mitigating heavy metal contamination in the poultry industry to ensure the safety and quality of poultry products.


Assuntos
Água Potável , Metais Pesados , Animais , Galinhas , Cádmio , Paquistão , Chumbo , Monitoramento Ambiental , Zinco
4.
J Mol Graph Model ; 126: 108638, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37757650

RESUMO

Dynamical variation of physical properties in a controllable fashion provides exciting possibilities to obtain multifunctional materials. In this work, layer-sliding is employed to modify the structural, interfacial electronic and optical properties of unintercalated and Mg-intercalated two-dimensional (2D) van der Waals heterostructure (vdW-HS) consisting of buckled silicene and hexagonal boron nitride (hBN). The most stable stacking configuration of silicene over hBN is screened out and then intercalated with Mg at the interface. Dynamical-dependent changes in the properties of vdW-HS are performed by sliding silicene over hBN monolayer in the absence and presence of the intercalant. Layer-sliding is carried out in equal length intervals, and various parametric quantities related to the physical characteristics of the vdW-HS are repeatedly calculated and compared. Apart from various parametric quantities, stability of unintercalated and Mg-intercalated vdW-HS is also checked by means of relative total energies, binding energies and vdW gaps along the sliding pathway. Comparison of binding energies shows that the un-slided, half-slided, and fully-slided Mg-intercalated vdW-HS are 1.52, 1.44 and 1.42 eV more stable than the unintercalated vdW-HS. Opening of a small band gap of 12, 31 and 28 meV for un-slided, half-slided and fully-slided unintercalated vdW-HS, respectively, is worth mentioning. To study the interfacial electronic behavior, planar average charge density difference (Δρ) and charge transfer (ΔQ) are also calculated and varied via layer-sliding. Further, we calculated diverse optical spectra such as the complex dielectric function (DF), electron energy loss function [L(ω)], diagonal components of dielectric tensor [ε(iω)], refractive index [n(ω)], extinction coefficient [k(ω)], absorption coefficient [α(ω)], and reflectivity [R(ω)] for un-slided, half-slided and fully-slided unintercalated and Mg-intercalated vdW-HS. Interestingly, the polarization and energy losses have been reduced in the case of Mg-intercalated vdW-HS. The suggested layer-sliding method can be established as a general scheme for bringing multifunctionality into a layered material.


Assuntos
Eletrônica , Elétrons , Fatores de Transcrição
5.
J Mol Graph Model ; 127: 108694, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38103400

RESUMO

Efficient strategies for modifying the characteristics of van der Waals (vdW) layered materials in a precise and reversible mode remain challenging. Our suggested method for customization entails the implementation of layer-sliding and intercalation. In this work, a norm-conserving approach within the context of density functional theory has been used to examine the electronic and optical properties of two-dimensional (2D) van der Waals heterostructure (vdWHS), which is modeled by using 2D zirconium dioxide (1T-ZrO2) and molybdenum disulfide (1T-MoS2) monolayers of similar phase. Both contributing monolayers have similar lattice structures, with a minimum lattice mismatch of 0.83 %, and have corrugation on both sides that can successfully retain foreign species at the vdW-gap. In the next step, interfacial engineering through Li-intercalation and layer-sliding was employed to modify physical properties of the vdWHS. It is the worth mentioning that a narrow bandgap of 0.102 eV (0.22 eV) has been observed in the unintercalated ZrO2/MoS2 vdWHS when employing PW-LDA (hybrid-functional). Li-intercalation and sliding process significantly influenced the electronic properties of the studied vdWHS. Furthermore, un-slided and fully-slided Li-intercalated vdWHS exhibit an increase in the vdW-gap by 3.78 % and 27.14 %, respectively, as compared to unintercalated vdWHS. To further understand the electrical behaviour at the interface of contributing monolayers, a comparative study has also been made for the variation in the planar average charge density difference, charge transfer, and interface dipole moment for unintercalated and intercalated vdWHS. In the unintercalated vdWHS, the calculated values of ΔQ and µ(z) provide evidence of significant charge transfer from 1T-ZrO2 to 1T-MoS2 before sliding, whereas in the fully-slided vdWHS, there is 80.11 % more charge transfer from 1T-MoS2 to 1T-ZrO2. Li-intercalation increases the magnitude of ΔQ (by 90.27 %) near 1T-MoS2, indicating a sufficient quantity of charge transfer from the 1T-MoS2 monolayer. The results of the anisotropic analysis show that the calculated in-plane and out-of-plane components of the real and imaginary parts of the dielectric function differ significantly. The optical absorption and energy losses of Li-intercalated vdWHS experience a substantial decrease of about 90 % and 50 %, respectively, as compared to unintercalated vdWHS. Our employed method promotes the notion that interfacial engineering through simultaneous layer-sliding and intercalation approach can be used to regulate and modify the physical properties of 2D insulator/metal based vdWHS.


Assuntos
Lítio , Molibdênio , Anisotropia , Eletricidade , Eletrônica , Fatores de Transcrição
6.
Trop Anim Health Prod ; 55(4): 283, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37535251

RESUMO

An experimental work was conducted to evaluate the effects of Saccharomyces cerevisiae live cells and its culture on dry matter intake (DMI), milk yield, milk composition, body condition score, selected blood metabolites, feed conversion efficiency (FCE), nutrient digestibility, body weight gain, and economics of milk production in lactating multiparous Nili-Ravi buffaloes. In total, 20 buffaloes of age 5 years ± 6 months and weighing 550 ± 20 kg were selected and assigned to four dietary treatments (n=5 buffalo/treatment) under completely randomized design. The dietary treatments include treatment 1 (T1) control, treatment 2 (T2) 5g/head live yeast, treatment 3 (T3) 5g/head yeast culture, and treatment 4 (T4) 10 g/head yeast culture per day for 60 days excluding 14 days as an adjustment period. The results indicated that T4 showed significant (p<0.05) improvement in DMI, milk yield and components, blood glucose level, digestibility of nutrients, and body weight gain while significant decrease in blood urea nitrogen as compared to other treatment groups. Body condition score was not affected among treatments. In conclusion, yeast culture supplementation significantly improved (p <0.05) milk yield, milk composition, DMI, body weight gain, blood glucose level, and digestibility while significantly decreased blood urea level as compare to control. Economic return was also improved. BCS was not improved. Comparatively, yeast culture showed significant improvement in growth and productive performance as compare to live yeast. Meanwhile, 10-g yeast culture showed better results as compare to 5-g yeast culture.


Assuntos
Bison , Búfalos , Animais , Feminino , Ração Animal/análise , Glicemia/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Digestão , Lactação , Leite/metabolismo , Saccharomyces cerevisiae , Aumento de Peso
7.
Anim Biosci ; 36(6): 869-878, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36397692

RESUMO

OBJECTIVE: Hyperketonemia remains a major metabolic issue of serious milk production and a major health concern in early lactation cows. Oral supplementation of glucose precursors (GP) can be used to prevent hyperketonemia in dairy cows. The objective of this study was to compare the beneficial effects of orally supplementing a mixture of GP on metabolic health indicators and milk production status of primiparous (PP) and multiparous (MP) dairy cows. METHODS: Twenty-eight Holstein cows were blocked by expected date of parturition, previous lactation yield, and parity. The cows were randomly allocated to one of the four treatment groups (n = 7 cows/group) based on their parity and GP supplementation: i) PP cows fed basal diet only (PP-CON), ii) PP cows with oral supplementation of GP (PP-GP), iii) MP cows fed basal diet only (MP-CON), and iv) MP cows with oral supplementation of GP (MP-GP). Glucose precursor (glycoline liquid) was orally drenched (300 mL/d) in GP cows from 7 days prepartum through 7 days postpartum. Other than GP supplementation, all cows were fed similar pre- and postpartum basal diets. RESULTS: In both pre- and postpartum periods, serum glucose concentration was increased, whereas ß-hydroxybutyrate and free fatty acids were decreased in GP cows compared with the CON cows. Milk yield and milk components were statistically not different between GP and CON cows over the first 9 week of lactation. The yield of actual milk, energy-corrected milk, 63-days cumulative milk, colostrum yield, and calf birth weight remained higher in MP cows compared with PP cows. CONCLUSION: Oral drenching of GP around calving can be recommended to successfully improve the metabolic health and reduce the negative effects of hyperketonemia not only in MP but also in PP dairy cows.

8.
Biomicrofluidics ; 16(6): 064106, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36536792

RESUMO

Paper has attracted significant attention recently as a microfluidic component and platform, especially in passive pumping devices due to its porous and uniform absorbing nature. Many investigations on 1D and 2D fluid flows were carried out. However, no experimental work has been reported on the three-dimensional effect in porous geometry to improve pumping characteristics in microchannels. Therefore, in this study, the fluid flow in 3D paper-based passive pumps was investigated in microchannels using cylindrical pumps. The effect of pump diameter, porosity, and programmability was investigated to achieve desired flow variations. The results indicated that the flow rate of water increased with an increase in the diameter and porosity of paper pumps. Maximum flow rates achieved for 14 mm diameter pumps of 0.5 and 0.7 porosities were 5.29 mm3/s (317.4 µl/min) and 6.97 mm3/s (418.2 µl/min), respectively. The total volume of fluid imbibition ranged between 266 and 567 µl for 8 and 14 mm diameter pumps, respectively. Moreover, 3D passive pumps can transport larger volumes of liquid with an improved flow rate, programmability, and control, in addition to being inexpensive and simple to design and fabricate. Most importantly, a single 3D paper pump showed an increasing, decreasing, and constant flow rate all in a single microchannel. With these benefits, the passive pumps can further improve the pumping characteristics of microfluidic platforms enabling a cost effective and programmable point-of-care diagnostic device.

9.
Rev Med Virol ; 32(3): e2287, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34428335

RESUMO

Chikungunya virus (CHIKV) is one of the emerging viruses around the globe. It belongs to the family Togaviridae and genus Alphavirus and is an arthropod borne virus that transmits by the bite of an infected mosquito, mainly through Aedes aegypti and Aedes albopcitus. It is a spherical, enveloped virus with positive single stranded RNA genome. It was first discovered during 1952-53 in Tanganyika, after which outbreaks were documented in many regions of the world. CHIKV has two transmission cycles; an enzootic sylvatic cycle and an urban cycle. CHIKV genome contains 11,900 nucleotides and two open reading frames and shows great sequence variability. Molecular mechanisms of virus host-cell interactions and the pathogenesis of disease are not fully understood. The disease involves three phases; acute, post-acute and chronic with symptoms including high-grade fever, arthralgia, macupapular rashes and headache. There is no licensed vaccine or specific treatment for CHIKV infection. This lack of specific interventions combined with difficulties in making a precise diagnosis together make the disease difficult to manage. In this review we aim to present the current knowledge of global epidemiology, transmission, structure, various aspects of diagnosis as well as highlight potential antiviral drugs and vaccines against CHIKV.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Animais , Antivirais , Febre de Chikungunya/patologia , Vírus Chikungunya/genética , Surtos de Doenças , Humanos
10.
J Basic Microbiol ; 58(1): 3-16, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29131357

RESUMO

Zika virus is one of the emerging viruses and is of significant threat to human health globally. It is a mosquito borne flavivirus similar to dengue, yellow fever, and West Nile viruses. It was reported about 5 decades ago and then it spreads to different parts of the world. Large outbreaks were reported on Yap Islands in 2007. Now it has gained wide attention globally by health communities. Major vector for virus transmission is Aedes aegypti mosquito. ZIKV infection is mostly asymptomatic but it is also responsible to cause mild influenza like illness to serious manifestations. There is no specific anti-viral treatment is available for ZIKV infection. The virus disseminates very fast due to which it possesses a serious threat especially in those areas where there is lack of specific immunity against virus. Little knowledge is available on its transmission and pathogenicity. Although virus was discovered years ago but its genomic structure is not clearly understood yet. In this review we focus on the current knowledge of epidemiology of ZIKV, its transmission, its structural biology, different aspects of diagnosis and diagnostic challenges as well as highlighted appropriates antiviral drugs and vaccines regarding treatment.


Assuntos
Aedes/virologia , Mosquitos Vetores/virologia , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/transmissão , Zika virus/genética , África/epidemiologia , América/epidemiologia , Animais , Ásia/epidemiologia , Surtos de Doenças , Variação Genética , Humanos , Filogenia , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/genética , Vacinas Virais/administração & dosagem , Zika virus/química , Zika virus/imunologia , Zika virus/patogenicidade , Infecção por Zika virus/diagnóstico , Infecção por Zika virus/tratamento farmacológico
11.
Braz. arch. biol. technol ; 59: e16160282, 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951304

RESUMO

ABSTRACT The presence of geneticdiversity is of great importance in improving wheat traits and developing strategies for optimal conservation of germplasm. Genetic diversity was assessed among common wheat cultivars using RAPD (Random Amplified Polymorphic DNA) markers at the Center of Agriculture, Biochemistry and Biotechnology (CABB), University of Agriculture, Faisalabad. RAPD primers were used among 14 Pakistani wheat cultivars, to screen the progenies and for the identification of the genes of interest. The polymorphic information content (PIC), was measured as the percentage of polymorphic fragments for all primers. A total of 583 bands(84% polymorphic) in all 14 wheat cultivars was amplified and discriminated all the wheat genotypes. The number of fragments amplified per primer ranged from 35 to 69 with an average of 48.52 fragments per primer averagely was observed. Population structure analysis anddandrogram showed distinct clustering among different wheat genotypes. Millat-11, Punjab-11, PBW-222 generated the maximum level of polymorphism, standing alone in the cluster while others are scatteredin different group.As a result, genetically numerous progenies are known, increasing the quality of sorts collections by broadening the genetic base of wheat cultivars. This study additionally indicates that RAPD markers allow quicker response and provide high throughputprocedure of accessions from a variety assortment to assess genetic diversity among wheat genotypes.

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