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1.
Sci Rep ; 14(1): 3467, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38342938

RESUMEN

Tetragonal graphene nano-capsule (TGC), a novel stable carbon allotrope of sp2 hybridization is designed and doped with phosphorus (P) to study the O3 and SO2 gas sensitivity via density functional theory calculation. Real frequencies verified the natural existence of both TGC and P-doped TGC (PTGC). Both TGC and PTGC suffer structural deformations due to interaction with O3 and SO2 gases. The amount of charge transfer from the adsorbent to the gas molecule is significantly greater for O3 adsorption than SO2 adsorption. The adsorption energies for TGC + O3 and PTGC + O3 complexes are - 3.46 and - 4.34 eV respectively, whereas for TGC + SO2 and PTGC + SO2 complexes the value decreased to - 0.29 and - 0.30 eV respectively. The dissociation of O3 is observed via interaction with PTGC. A significant variation in electronic energy gap and conductivity results from gas adsorption which can provide efficient electrical responses via gas adsorption. The blue/red shift in the optical response proved to be a way of detecting the types of adsorbed gases. The adsorption of O3 is exothermic and spontaneous whereas the adsorption of SO2 is endothermic and non-spontaneous. The negative change in entropy verifies the thermodynamic stability of all the complexes. QTAIM analysis reveals strong covalent or partial covalent interactions between absorbent and adsorbate. The significant variation in electrical and optical response with optimal adsorbent-gas interaction strength makes both TGC and PTGC promising candidates for O3 and SO2 sensing.

2.
Nanoscale Adv ; 6(4): 1218-1226, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38356625

RESUMEN

The sensitivity of a RbSnCl3 perovskite 2D layer toward NH3, SO2, and NO toxic gases has been studied via DFT analysis. The tri-atomic layer of RbSnCl3 possessed a tetragonal symmetry with a band gap of 1.433 eV. The adsorption energies of RbSnCl3 for NH3, SO2 and NO are -0.09, -0.43, and -0.56 eV respectively with a recovery time ranging from 3.4 × 10-8 to 3.5 ms. RbSnCl3 is highly sensitive toward SO2 and NO compared to NH3. The adsorption of SO2 and NO results in a significant structural deformation and a semiconductor-to-metal transition of RbSnCl3 perovskite. A high absorption coefficient (>103 cm-1), excessive optical conductivity (>1014 s-1), and a very low reflectivity (<3%) make RbSnCl3 a potential candidate for numerous optoelectronic applications. A significant shift in optical responses is observed through SO2 and NO adsorption, which can enable identification of the adsorbed gases. The studied characteristics signify that RbSnCl3 can be a potential candidate for SO2 and NO detection.

3.
PLoS One ; 18(11): e0293553, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37910451

RESUMEN

Guavas (Psidium guajava) are regarded as one of the most perishable commodities, primarily owing to their climacteric characteristics and heightened metabolic processes, resulting in a faster rate of softening. Edible coating is a natural ingredient that is employed as an alternative to extend the shelf life of fruits while also providing bioactive and functional compounds. Aloe vera gel is predominantly used for this purpose due to its widespread availability. Various concentrations of aloe vera-based coating formulation (25%, 50%, 75%, and 100%) were applied on fresh whole guava by dipping method. The guava was stored at a refrigerated condition (4°C) and weight loss, color, firmness, vitamin C, total phenol, and pH change were observed in this research. A significant effect of aloe vera coating was found over the storage period. Aloe vera treatment lowered the weight loss, and retarded the texture and color compared to the control sample throughout the 28 days of storage. Vitamin C and total phenol content remined high at 141.4 mg/100g and 219.6 mg GAE/100g respectively in a 100% aloe vera coated sample after 28 days of storage compared to the control. Among 25%, 50%, 75%, and 100% aloe vera coated sample, 100% aloe vera was found to be the best coating material to prevent physical changes in fresh guava.


Asunto(s)
Aloe , Psidium , Frutas/metabolismo , Psidium/química , Conservación de Alimentos/métodos , Ácido Ascórbico/metabolismo , Fenoles/farmacología , Vitaminas/análisis , Pérdida de Peso
4.
Phys Chem Chem Phys ; 25(46): 32261-32272, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37988166

RESUMEN

Heavy metal removal from polluted environments is one of the vital research areas for better and healthier living. In this research, C8 and B4N4 nanocage-like quantum dots are investigated for heavy metal (Cr) removal applications via density functional theory calculations. The adsorption of up to two Cr atoms has been studied in both air and a water medium. The adsorption of Cr atoms results in significant structural deformation of the adsorbents with a high adsorption energy of -8.74 and -5.77 eV for C8 and B4N4 nanostructures, respectively, which is further increased with an increasing number of Cr atoms. All adsorbents and complex structures showed real vibrational frequencies. Mulliken charge and electrostatic potential analysis reveal a significant charge transfer between adsorbate-adsorbent. The adsorption process causes a decrease in the energy gap of the adsorbents. All the reactions in this study were spontaneous and thermodynamically ordered. QTAIM analysis verifies that the interactions of the adsorbents with Cr atoms are strong partial covalent. The study's findings make C8 and B4N4 nanostructures potential candidates for Cr-detection and removal applications.

5.
Heliyon ; 9(9): e19407, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37809619

RESUMEN

In this industrial era, the use of low-dimensional nanomaterials as gas sensors for environmental monitoring has received enormous interest. To develop an effective sensing method for ethylene oxide (EO), DFT computations are conducted using method ωB97X-D and B3LYP with 6-31G(d,p) basis set to evaluate the adsorption behavior of ethylene oxide gas on the surfaces of pristine, as well as Scandium and Titanium decorated B12N12, Al12N12, and Al12P12 nanocages. Several properties like structural, physical, and electronic are studied methodically to better understand the sensing behavior. Scandium-decorated aluminum phosphate and boron nitride nanocages were shown to perform better in terms of adsorption properties. The short recovery time observed in this study is beneficial for the repetitive use of the gas sensor. The Natural Bond Orbital and molecular electrostatic potential analysis demonstrated a substantial quantity of charge transfer from adsorbate to adsorbents. The bandgap alternation after adsorption shows an influence of adsorption on electronic properties. The interactions of adsorbate and adsorbents are further studied using the ultraviolet-visible predicted spectrum, and quantum theory of atoms in molecules all of which yielded promising findings.

6.
Heliyon ; 9(7): e17886, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37539100

RESUMEN

First Principle DFT calculations employing the B3LYP/LanL2DZ/SDD level of theory were used to analyze the various characteristics of boron nanoclusters (B6, B8, and B10). These pure structures were further doped with four transition metals (Ta, Ti, Tc, and V) to examine the enhancement of the pure structures' structural, electrical, and optical features. To study structural stability, we have estimated cohesion energy and imaginary frequencies. Cohesion energies were entirely negative, with a range of -3.37 eV to -8.07 eV, and most constructions had no imaginary frequencies, indicating their structural occurrences. The calculated adsorption energy suggests that the order of stability of the pristine boron nanoclusters is B10>B8>B6, and TcB10 and Tc2B10 are the more stable structures. Mulliken charge, DOS, HOMO-LUMO, and the HOMO-LUMO gap have all been examined in-depth to provide insight into electrical characteristics. UV-Vis and CD measurements show the doped boron nanoclusters have excellent optical properties. Aside from calculating thermodynamic functions, we have also calculated the global DFT parameters, which give us a deep quantum mechanical understanding of the optimized structure for further research and applications in the field of science and technology.

7.
J Family Med Prim Care ; 12(1): 21-26, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37025210

RESUMEN

Introduction: Obesity had been the most neglected public health problem increasing at an alarming rate affecting both the developed and developing countries. Periodontitis is a chronic inflammatory disease which is highly prevalent worldwide affecting 20-50% of the global population. Thus, a research was conducted to evaluate the relationship between obesity and periodontal disease among 35-44-year-old patients who were visiting the Oral Medicine and Radiology Department (OMDR) in TMDCRC, Moradabad. Objective: To know the prevalence of obesity and periodontal health. To record the body mass index (BMI) and to co-relate with periodontal disease. To recommend preventive measures for periodontitis and the obese population. Materials and Method: A cross-sectional study was conducted in the Department of OMDR, TMDCRC, Moradabad. A total of 566 subjects were examined aged 35-44 years visiting the out patient department (OPD) of the OMDR Department. Informed consent was obtained from the participants. Questionnaire-based proforma was used comprising information regarding oral hygiene practices, frequency of toothbrushing, and method of brushing. A World Health Organization (WHO)-modified 2013 assessment form was used to record the periodontal status of the participants. Results: The examination of 550 subjects was done. It was found that there is a significant association of periodontal disease in factors like BMI, age, gender, smoking status, and loss of attachment (LOA) is found in BMI, gender, smoking status, and smoking frequency. It was also found that there is a significant association of the community periodontal index (CPI) scores in obese individuals. Conclusion: The main aim is to find and control the risk factor and eliminate it. Our study confirms that obesity is one of the risk indicators of periodontitis. With the scope and limitations of the study, it has been concluded that obesity and periodontitis have a significant relationship with each other. This study states the importance of good oral hygiene maintenance in obese and normal patients.

8.
Toxics ; 11(4)2023 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-37112534

RESUMEN

The fall armyworm (FAW), Spodoptera frugiperda, is one of the most devastating invasive polyphagous pests, which has attracted recent global attention by developing resistance to various insecticidal active ingredients with independent mode of action. Fluxametamide, a newly commercialized isoxazoline insecticide, is exceptionally selective towards several lepidopteran pests. The present study aimed to evaluate resistance risk in FAW to fluxametamide and the fitness costs associated with fluxametamide resistance. A field-collected and genetically mixed population of FAW was artificially selected through continuous exposure to fluxametamide. After successive selection of 10 generations, there was no obvious increase in the LC50 (RF: 2.63-fold). The realized heritability (h2) of fluxametamide resistance was estimated as h2 = 0.084 using a quantitative genetic approach. Compared with the susceptible F0 strain, the Flux-SEL (F10) strain of FAW displayed no significant cross-resistance to broflanilide, chlorantraniliprole, fipronil, indoxacarb, lambda cyhalothrin, spinetoram, and tetraniliprole, except emamectin benzoate (RF: 2.08-fold). Increased activity of glutathione S-transferase (ratio 1.94) was observed in the Flux-SEL (F10) strain of FAW, while the cytochrome P450 and carboxylesterase activities were not altered. The fluxametamide-selection significantly affected the development and reproductive traits of FAW with a lower R0, T and relative fitness (Rf = 0.353). The results alluded that the risk of fluxametamide resistance evolution in FAW is relatively lower; however, proactive implementation of resistance management approaches should be done to maintain the field efficacy of fluxametamide against FAW.

9.
Electrophoresis ; 44(7-8): 711-724, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36720044

RESUMEN

A number of microfluidic systems of interest essentially consist of micro-scaled channels/tubes, whose walls are inherently rough. The novelty of the current study lies in exploring the impact of the wall roughness on mass transfer in the case of flow through a microtube with porous wall. The current investigation is possibly the first attempt at exploring the effect of mass transfer for a porous-walled, rough microtube, as earlier studies were limited to the analysis of hydrodynamic and thermal effects only in an impervious microtube. In particular, the effects of the corrugation amplitude and the wavenumber on the mass transport have been assessed in detail in this work, via a combination of perturbation approximations and numerical analysis. Several interesting revelations are elicited regarding the effects of these pertinent parameters on the mass transfer coefficient, permeation flux, wall surface concentration, and delivery flux of the neutral solute. It has been unveiled that it is possible to enhance the solute mass flux by 10% via appropriate tuning of corrugation amplitude. The findings of the study can help in better understanding of mass transport for a porous-walled, rough microtube, which has critical relevance in several important applications such as micromixers, targeted drug delivery, and so on.


Asunto(s)
Electroósmosis , Modelos Teóricos , Porosidad , Microfluídica , Soluciones
10.
PeerJ ; 10: e14360, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36353600

RESUMEN

Evaluation and identification of resistant donors for brown planthopper (BPH) Nilaparvata lugens (Stål.), an economically important insect pest of rice, is a continuous process to develop new resistant rice varieties. However, several rice landraces of north-eastern India are not yet characterized for BPH resistance. In the present study, a set of 218 rice landraces were screened in both greenhouse and open-field conditions for three consecutive years, and thereafter forty selected promising entries were explored to evaluate their phenotypic and genotypic reactions against BPH biotype 4. Based on phenotypic evaluations, five landraces were identified as resistant, while 31 were moderately resistant, and grouped under the major cluster I and II, respectively, in a circular dendrogram. Antixenosis and antibiosis studies of these landraces divulged that, compared to the susceptible check variety, resistant landraces exhibited the lowest feeding rate, survival, and nymphal and adult settling, but higher frequency of unhatched eggs of BPH. Un-infested resistant landraces registered higher levels of ascorbic acid, oxalic acid and crude silica, however, elevated levels of total free amino acid, potassium and crude silica were observed under BPH herbivory. The present study focuses on identifying new donors having BPH resistance resources which could be useful in genomic studies for the development of BPH biotype 4 resistant rice varieties.


Asunto(s)
Hemípteros , Oryza , Animales , Hemípteros/genética , Herbivoria , India , Oryza/genética
11.
Environ Sci Pollut Res Int ; 29(33): 50566-50583, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35235117

RESUMEN

Graphitic carbon nitride (g-C3N4) was employed as a sacrificial substructure and two-dimensional support to develop magnetic cobalt ferrite-carbon nitride (CoFe2O4/g-CN) composite via a one-step solid combustion method. The catalyst activated peroxymonosulphate (PMS), through the interconversion of Co2 + /3+|surf. and Fe2 + /3+|surf. on its surface for degradation of reactive dyes (RDs). Excellent ferromagnetic nature (44.15 emu g-1) of the catalyst led to its efficient magnetic separation. With an optimum catalyst and PMS dose of 0.4 g L-1 and 1.5 g L-1, 99% RD removal was achieved for textile effluent (pH 9.5-10), under UV irradiation (48 W). In-depth radical scavenging experiments and EPR analysis confirmed the dominance of radical-based degradation process. Plausible degradation and mineralization pathways of RDs were proposed through identification of intermediates by LCMS/MS analysis. In brief, this study elucidates an exclusive strategy towards the use of g-C3N4 as fuel for facile synthesis of magnetic CoFe2O4/g-CN as a remarkable photocatalyst for activation of PMS towards mineralization of various industrially relevant RDs.


Asunto(s)
Colorantes , Peróxidos , Peróxidos/química , Fotólisis , Textiles
12.
Biol Trace Elem Res ; 200(12): 5052-5063, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35061144

RESUMEN

This study was aimed to explore the effect of astaxanthin (ASTX) and copper (Cu) supplementation on the growth, immunity, antioxidant, and blood biochemical status of growing Murrah buffalo heifers. Twenty-eight Murrah buffalo heifers were selected and randomly divided into 4 groups (n = 7) after blocking by body weight (BW) (129.86 ± 5.37 kg) and age (9.05 ± 1.02 months). The heifers were fed basal total mixed ration diet without supplementation (CON) or with ASTX (0.20 mg/kg BW; AX), Cu (10 mg/kg DM; CU), or ASTX + Cu (0.20 mg/kg BW + 10 mg/kg DM; AX + CU) for 90 days of study period. The result showed that BW and dry matter intake (DMI) were significantly higher (P < 0.05) in AX + CU than that in other groups. The average daily gain (ADG) and feed conversion efficiency (FCE) were statistically higher (P < 0.05) in treatments than the values observed in CON. The feed conversion ratio (FCR) was reported significantly lower (P < 0.05) in the AX + CU group followed by AX, CU, and CON groups. The total leukocytes count (TLC), lymphocytes, and total immunoglobulin (TIG) were statistically higher (P < 0.05) in AX + CU groups than that found in other groups. However, neutrophil % decreased (P < 0.05) in the AX + CU group than its level in other groups. Superoxide dismutase (SOD), catalase (CAT), and total antioxidant (TAA) levels were observed higher (P < 0.05) in treatments supplemented with ASTX, Cu, or both than CON group. Thiobarbituric acid reactive substance (TBARS) concentration was lower (P < 0.05) in treatments than its level found in the CON group. Glucose level was higher (P < 0.05); however, non-esterifies fatty acid (NEFA) was lower (P < 0.05) in AX + CU than that in others groups. The level of cholesterol (CH), HDL cholesterol (HDL-CH), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were reported lower (P < 0.05) in the AX + CU group followed by CU, AX, and CON groups. The copper (Cu) level was higher (P < 0.05) in CU and AX + CU than AX and CON groups. The result of the present study indicated that the supplementation of ASTX, Cu alone, or their combination improved the growth, immunity, antioxidant status, and liver function of growing heifers.


Asunto(s)
Antioxidantes , Búfalos , Alanina Transaminasa , Fosfatasa Alcalina , Alimentación Animal/análisis , Animales , Antioxidantes/metabolismo , Aspartato Aminotransferasas , Peso Corporal , Catalasa , Bovinos , HDL-Colesterol , Cobre/metabolismo , Cobre/farmacología , Dieta/veterinaria , Suplementos Dietéticos , Ácidos Grasos no Esterificados , Femenino , Glucosa , Inmunoglobulinas , Superóxido Dismutasa , Sustancias Reactivas al Ácido Tiobarbitúrico , Xantófilas
13.
Ecol Food Nutr ; 61(4): 460-483, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35023791

RESUMEN

Despite Bangladesh's remarkable progress in agricultural production over the past few decades, household food and nutrition insecurity persist, especially in rural areas. The nutrition security and dietary diversity are even more critical for women of reproductive age among smallholders. This study examined household food insecurity and dietary diversity of women of reproductive age in the rural areas of northwest Bangladesh. Using cross-sectional data collected from 252 smallholder households, we measured household food insecurity and dietary diversity of women of reproductive age by the Household Food Insecurity Access Scale and the Minimum Dietary Diversity for Women, respectively. Determinants of household food insecurity were examined, and associations between household food insecurity and low dietary diversity were determined. The majority of the households were mildly insecure (51.2%) followed by moderately insecure (27.4%). The households felt anxiety of food insecurity for more than six months a year (Food Security Index = 2.10 out of 4.00). The mean food group consumed by women was 4.63 indicating low dietary diversity and dominance of diets by grains and dark green leafy vegetables. The findings also indicate a significant and positive association between household food insecurity and low dietary diversity of women. Education of household heads, household size, access to information sources, access to credit support, and perceived impacts of climate change on crop production were identified as determinants of household food insecurity. The study recommends that appropriate interventions be formulated to improve the food and nutrition security in the study areas.


Asunto(s)
Dieta , Abastecimiento de Alimentos , Agricultura , Bangladesh , Estudios Transversales , Femenino , Inseguridad Alimentaria , Humanos , Población Rural , Verduras
14.
Environ Sci Pollut Res Int ; 28(32): 43483-43506, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33835343

RESUMEN

Novel functionalized polymeric beads have been prepared by a simple phase inversion technique and its potential as an effective sorbent for reactive dyes is studied. Polyacrylonitrile was used as the base polymer for the beads that were further functionalized using diethylenetriamine. Scanning electron microscopy, FTIR spectroscopy, BET technique, TGA analysis, and zeta potential measurement were used for characterization of the functionalized beads. The adsorption characteristics of the beads were analyzed through adsorption isotherms. A first-principle-based pore diffusion-adsorption model was employed to study adsorption process of the functionalized beads and to determine various mass transfer parameters, i.e., mass transfer coefficient and effective pore diffusivity, in both single and multicomponent cases. For different reactive dyes, the beads have adsorption capacities in the range of 170-230 mg/g. Effects of different operating parameters, i.e., inlet concentration of solute, influent rate, and bed depth were studied to determine the breakthrough performance of the columns prepared with the beads. Industrial dye effluent, containing four reactive dyes at different initial concentrations, was used to study multicomponent adsorption in the columns. The regeneration efficiency of the beads was determined using aqueous cationic surfactant solution. Finally, scaling up of the fixed bed columns was carried out using a first principle-based transport model based on pore diffusion-adsorption processes.


Asunto(s)
Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Colorantes , Cinética , Textiles
15.
J Hazard Mater ; 403: 123624, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33264856

RESUMEN

In this study, the metal organic framework (MOF) ZIF-8 was investigated as potential adsorbent for heavy metal ions. The MOF powder was used further to prepare mixed matrix beads (MMBs) using polysulfone as the base material. Both the MOF powder and the MMBs were characterized using Field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller (BET) analyzer and zetasizer. Adsorption capacity of the MMBs were 164-220 mg/g for Pb and 92-161 mg/g for Cd. A fundamental pore diffusion-adsorption model was used to predict the batch kinetics for both single and multicomponent cases and effective pore diffusivities and mass transfer coefficients were determined. Mutual interactions among heavy metals were quantified using interaction parameters. ZIF-8, incorporated in the PSF matrix, plays the predominant role in capturing the metal ions through surface complexation with the NH and metal-OH groups. A first principle-based model involving convection, diffusion and adsorption was used to quantify the breakthrough behavior for the continuous fixed bed column using the MMBs. The column performance was tested with battery industry effluent. The saturated beads were suitably regenerated using 0.1(M) HCl solution. Finally, the model parameters were used for scaling up of the columns.

16.
Biol Trace Elem Res ; 194(2): 379-389, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31273682

RESUMEN

This study was conducted to investigate the effect of vanadium (V) supplementation on growth, metabolism, antioxidant, and immunological and endocrine variables in Hariana heifers. Eighteen indigenous Hariana heifers (body weight 130.0 ± 3.0 kg; age 10.0 ± 2.0 months) were randomly blocked into three groups, each comprising of six animals. All the animals were on same dietary plan except that the respective groups were additionally supplemented with 0.0, 2.5, and 5.0 mg of V/kg dry matter (DM), during the experimental period of 90 days. There was a linear increase (p < 0.05) in mean DMI and ADG in 5.0 mg of V/kg DM-supplemented group. However, the feed efficiency remained unaffected. Although no effects (p > 0.05) of V supplementation were observed on hemato-biochemical attributes, the mean plasma V concentration showed dose-dependent increase (p < 0.001) on V supplementation. The activity of SOD was significantly higher (p < 0.001), whereas mean values of LPO decreased linearly (p < 0.05) in V-supplemented groups. Plasma total antioxidant status (TAS) also increased linearly (p < 0.05) in V-supplemented groups. Plasma IgG levels increased linearly (p < 0.05). Plasma IGF-1 concentrations showed significant effect (p < 0.05) of V supplementation. Plasma T4 concentration increased linearly (p < 0.05). The results suggest that V supplementation may play a role in modulating the immunity and antioxidant status of growing Hariana heifers. Graphical Abstract.


Asunto(s)
Alimentación Animal , Antioxidantes , Alimentación Animal/análisis , Animales , Bovinos , Suplementos Dietéticos , Femenino , Inmunidad , Vanadio/farmacología
17.
Electrophoresis ; 41(7-8): 578-587, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31743466

RESUMEN

A soft nanochannel involves a soft interface that contains a polyelectrolyte layer (PEL) sandwiched between a rigid surface and a bulk electrolyte solution. Mass transfer of a neutral solute in a combined electroosmotic and pressure driven flow through a polyelectrolyte grafted charged nanochannel with porous wall is presented in this work. Assuming the PEL as fixed charged layer and PEL-electrolyte interface as a semi-penetrable membrane, analytical solutions were obtained for potential distributions (for small wall potential). Velocity profiles were also derived in the same domains, for both inside and outside the PEL. Convective-diffusive species balance equation was semi-analytically solved inside the PEL. Expression of length averaged Sherwood number was also obtained and effects of different parameters, namely, drag parameter (α), Debye parameter (κ¯) , and PEL thickness were studied in detail. The variation of permeate concentration and permeation flux across the porous wall was obtained.


Asunto(s)
Electroósmosis/métodos , Nanotecnología/instrumentación , Polielectrolitos/química , Porosidad , Soluciones , Electricidad Estática
18.
Biol Trace Elem Res ; 190(1): 65-75, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30238420

RESUMEN

Nickel (Ni) has not been elucidated as an essential mineral in dairy animals, though in plants and lower organisms, its role in activation of urease enzyme is well known. This study was conducted to evaluate the effect of Ni supplementation on intake, growth performance, urease activity, antioxidant and immune status, and energy and lipid metabolism in growing cattle. Eighteen growing Hariana heifers were randomly allocated into three groups on body weight (125 ± 3.0 kg) and age basis (10 ± 2.0 months). Feeding regimen was similar in all the groups except that treatment groups were supplemented with 0.0 (Ni0.0), 1.5 (Ni1.5), and 3.0 (Ni3.0) mg of Ni/kg dry matter (DM) in three respective groups. DM intake (DMI), average daily gain (ADG), feed efficiency, plasma urease activity, biomarkers of antioxidant and immune status, energy and lipid metabolism, and plasma Ni levels were observed during the 90-day experimental period. There was linear increase (p < 0.05) in mean DMI and ADG without affecting feed efficiency was observed in 3.0 mg of Ni/kg DM supplemented heifers. Dietary Ni supplementation showed linear increase (p < 0.05) in mean plasma urease activity. No effects of (p > 0.05) of Ni supplementation were observed on superoxide dismutase (SOD) and catalase (CAT) activity and plasma lipid peroxide (LPO) concentration; whereas, mean plasma total antioxidant status (TAS) showed linear decrease (p < 0.001) in Ni-supplemented groups. Adding Ni up to 3.0 mg of Ni/kg DM did not exert (p > 0.05) any effect on plasma total immunoglobulin and immunoglobulin G (IgG) concentrations. Mean plasma cortisol level showed negative association with supplemental Ni levels and concentration was found lowest (p < 0.05) in 3.0 mg of Ni/kg DM-added group. Dietary Ni supplementation did not affect mean plasma concentrations of glucose, cholesterol, triglyceride, and non-esterified fatty acids (NEFA). There was a linear increase (p < 0.001) in plasma Ni concentrations as the Ni concentrations increased in the diet. The results of present study indicated that dietary supplementation of 3.0 mg of Ni/kg DM improved performance of growing cattle by increasing urease activity.


Asunto(s)
Antioxidantes/metabolismo , Metabolismo de los Lípidos/efectos de los fármacos , Níquel/farmacología , Alimentación Animal , Animales , Peso Corporal/efectos de los fármacos , Bovinos , Suplementos Dietéticos , Metabolismo Energético/efectos de los fármacos , Femenino
19.
Electrophoresis ; 40(5): 720-729, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30362567

RESUMEN

Transport of salt through the wall of porous microtube is relevant in various physiological microcirculation systems. Transport phenomena based modeling of such system is undertaken in the present study considering a combined driving force consisting of pressure gradient and external electric field. Transport of salt is modeled in two domains, in the flow conduit and in the pores of porous wall of the microtube. The solute transport in the microtube is presented by convective-diffusive mass balance and it is solved using integral method under the framework of boundary layer analysis. The wall of the microtube is considered to be consisting of series of straight parallel cylindrical pores with charged inner surface. The solute transport through the pores is considered to be composed of diffusive, convective and electric potential gradient governed by Nernst-Planck equation. Transport in the microtube and pores is coupled through the osmotic pressure model for the solvent and Donnan equilibrium distribution for the solute. The simulated results agree remarkably well with the experimental data conducted by in-house experimental set up. The charge density of the porous wall is estimated through the minimization of errors involved between the experimental and simulated data for different operating conditions.


Asunto(s)
Electrólitos/química , Electroósmosis , Microfluídica , Simulación por Computador , Microfluídica/instrumentación , Microfluídica/métodos , Modelos Químicos , Porosidad , Cloruro de Sodio/química
20.
Vet World ; 11(4): 459-463, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29805210

RESUMEN

BACKGROUND AND AIM: In the recent past,few studies have been carried out in chicken to assess the effect of Azolla meal and raw Azolla feeding on the performance of chicken. If turkeys effectively use unconventional feedstuffs like Azolla without reducing the performance, it will increase the profitability of turkey business. Hence, a study was carried out to evaluate the effect of dried Azolla pinnata vis-a-vis raw Azolla as choice feeding on the growth, feed conversion ratio (FCR), blood biochemical attributes, and immune competence traits of growing turkeys under intensive system. MATERIALS AND METHODS: A total of 72, 8-week-old grower turkey poults of black variety were randomly distributed into three dietary treatments having three replicates each with eight birds. The birds of the control group (T1) were fed a basal diet (CP - 19.71% and ME - 2789.79 Kcal/kg), while the other group (T2) and choice-feeding group (T3) were fed 5% of basal diet replaced by dry Azolla powder on DM basis and ad libitumAzolla along with basal diet, respectively. RESULTS: There was no significant difference among the different groups in the average weekly weight gain during the entire experiment. FCR was significantly better (p<0.05) in the choice-feeding group compared to the other two experimental groups during 8-16 weeks of age. There was no significant difference among the treatment groups in any of the blood biochemical indices except plasma uric acid, which was significantly decreased (p<0.01) in T2 compared to T1 at 16 weeks of age. HA and IgM response to 1% sheep red blood cells (log2 titer) were numerically better in T2 and T3 compared to the T1. CONCLUSION: Thus, it may be inferred that choice feeding with Azolla, and basal diet may improve FCR without any adverse effect on blood biochemical attributes and immune competence traits.

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