Nanomaterials have significantly contributed in the field of nanomedicine as this subject matter has combined the usefulness of natural macromolecules with organic and inorganic nanomaterials. In ...this respect, various types of nanocomposites are increasingly being explored in order to discover an effective approach in controlling high morbidity and mortality rate that had triggered by the evolution and emergence of multidrug resistant microorganisms. Current research is focused towards the production of biogenic silver nanoparticles for the fabrication of antimicrobial metallic-polymer-based non-cytotoxic nanocomposite system. An ecofriendly approach was adapted for the production of silver nanoparticles using fungal biomass (Aspergillus fumigatus KIBGE-IB33). The biologically synthesized nanoparticles were further layered with a biodegradable macromolecule (chitosan) to improve and augment the properties of the developed nanocomposite system. Both nanostructures were characterized using different spectrographic analyses including UV-visible and scanning electron microscopy, energy dispersive X-ray analysis, dynamic light scattering, and Fourier transform infrared spectroscopic technique. The biologically mediated approach adapted in this study resulted in the formation of highly dispersed silver nanoparticles that exhibited an average nano size and zeta potential value of 05 nm (77.0%) and - 22.1 mV, respectively with a polydispersity index of 0.4. Correspondingly, fabricated silver-chitosan nanocomposites revealed a size of 941 nm with a zeta potential and polydispersity index of + 63.2 mV and 0.57, respectively. The successful capping of chitosan on silver nanoparticles prevented the agglomeration of nanomaterial and also facilitated the stabilization of the nano system. Both nanoscopic entities exhibited antimicrobial potential against some pathogenic bacterial species but did not displayed any antifungal activity. The lowest minimal inhibitory concentration of nanocomposite system (1.56 µg ml
) was noticed against Enterococcus faecalis ATCC 29212. Fractional inhibitory concentration index of the developed nanocomposite system confirmed its improved synergistic behavior against various bacterial species with no cytotoxic effect on NIH/3T3 cell lines. Both nanostructures, developed in the present study, could be utilized in the form of nanomedicines or nanocarrier system after some quantifiable trials as both of them are nonhazardous and have substantial antibacterial properties.
Adequate sleep is integral to better mental health and facilitates students' learning. We aimed to assess sleep quality among medical students and to see whether it was associated with their mental ...health (e.g., depression, anxiety, and stress) and academic performance.
A total of 206 responded, and 95 of them had complete data on demography, lifestyle, academic performance, sleep quality (Pittsburgh Sleep Quality Index), and mental health (Depression Anxiety Stress Scales). The prevalence of poor sleep was 63.2%; it was higher among students who were physically inactive and had more screen time. Poor sleepers demonstrated higher academic performance than sufficient sleepers (p = 0.04). The prevalence of depression, anxiety, and stress were 42%, 53%, and 31% respectively. Sleep quality was significantly associated with depression (p = 0. 03), anxiety (p = 0.007), and stress (p = 0.01).
There is little available evidence of associations between the various dimensions of women's empowerment and contraceptive use having been examined--and of how these associations are mediated by ...women's socio-economic and demographic statuses. We assessed these phenomena in Pakistan using a structured-framework approach.
We analyzed data on 2,133 women who were either using any form of contraceptive or living with unmet need for contraception. The survey was conducted during May - June 2012, with married women of reproductive age (15-49 years) in three districts of Punjab. The dimensions of empowerment were categorized broadly into: economic decision-making, household decision-making, and women's mobility. Two measures were created for each dimension, and for the overall empowerment: women's independent decisions, and those taken jointly by couples. Contraceptive use was categorized as either female-only or couple methods on the basis of whether a method requires the awareness of, or some support and cooperation from, the husband. Multinomial regression was used, by means of Odds Ratios (OR), to assess associations between empowerment dimensions and female-only and couple contraceptive methods.
Overall, women tend to get higher decision-making power with increased age, higher literacy, a greater number of children, or being in a household that has superior socio-economic status. The measures for couples' decision-making for overall empowerment and for each dimension of it showed positive associations with couple methods as well as with female-only methods. The only exception was the measure of economic empowerment, which was associated only with the couple method.
Couples' joint decision-making is a stronger determinant of the use of contraceptive methods than women-only decision-making. This is the case over and above the contribution of women's socio-demographic and economic statuses. Effort needs to be made to educate women and their husbands equally, with particular focus on highly effective contraceptive methods.
Synergistic integration based on some transition-metal (TM) derived compounds is a unique and appealing technique, especially toward oxygen evolution reaction (OER) under alkaline circumstances. ...Herein, we present a cobalt-selenide (CoSe2) and cobalt-oxide (Co3O4) based composite (CSCO-2) material through a wet chemical method. As-prepared catalyst has been analyzed for various physicochemical characterizations. CSCO-2 offers efficient OER performance in 1.0 M KOH with an overpotential of 252 mV at current density of 20 mA/cm2, with a low Tafel slope value of 69 mV/dec. Importantly, as-prepared catalyst shows stability of 48 h for longer electrochemical performance as a potential candidate for OER.
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•Robust CoSe2 and Co3O4 based electrocatalyst for OER in the alkaline media.•Electrochemical efficiency with lower overpotential of 252 mV and Tafel slope of 69 mV/dec.•Having an electrochemical surface area of 367.5 cm2.•Stability for 48 h as longer performance.
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•Potential of GrOAgNPs embedded in CA nanofibers for wound dressings was studied.•GrO and nanofibers can adsorb and transport wound fluid keeping moist environment.•GrO and nanofibers ...promote tissue and vascular regeneration and accelerate healing.•The AgNPs protect from microbial contaminations and infections.•Anchored AgNPs on GrO and embedded in nanofibers protect from silver’s toxicity.
Effective and accelerated wound healing requires extensive care and robust wound management. Biomedical merits of GrO, antimicrobial properties of AgNPs and potential of CA nanofibers form highly desirable combination for a wound dressing construct. The AgNPs anchored on GrO and embedded in CA nanofiber matrix help avoid harmful side-effects of prolonged and excessive silver use. The GrOAgNPs were synthesized by hydrothermal process, added into CA solution and electrospun to fabricate the wound dressing construct. Three different concentrations of GrOAgNPs (2%, 4% and 6%) were used in the fabrication of nanofibers. The disk diffusion and relative viable cells (%) results confirmed effective bacteriostatic and bactericidal characteristics of CA/GrOAgNPs against E. coli and S. aureus bacteria which increased with successive addition of the GrOAgNPs. The research findings confirmed CA/GrOAgNP as potential candidate for wound healing applications.
Traditional uses of plants are one of the important starting points in search of newer and more effective bioactive drug.
Rosa brunonii
(plant’s family; Rosaceae) is an ethnomedicinal shrub found in ...lesser Himalaya region. In traditional medicines, it is used as “blood purifier, to stimulate wound healing, to treat infectious diseases”. So, by considering the medicinal potential of
Rosa brunonii
, the methanolic fruit’s extract was tested against two gram positive and three gram negative bacteria by agar well diffusion method. The maximum antibacterial potential was noticed against
Klebsiella pneumoniae
(94 ± 0.3 mm inhibition zone, MIC = 62.5 ± 1.1 µg/mL), while minimum antibacterial activity was shown by the plant extract against
Bacillus subtilis
(MIC = 250 ± 7.2 µg/mL). The cytotoxic properties of crude methanolic extract were determined by brine shrimp lethality test. A dose-dependent cytotoxic effect was observed for the plant extract at
p
< 0.05, F (3,8) = 1.58 with LD
50
220.95 ± 1.03 µg/mL. Antitumor potential was evaluated by potato disk antitumor bioassay. Fruit’s extract of
R. brunonii
showed maximum tumor inhibition at 1000 µg/mL by 72.73% with IC
50
= 655.65 ± 0.03 µg/mL. Preliminary phytochemical analysis revealed that extract is devoid of alkaloid but rich in phenolics. Total phenolic and flavonoid contents were determined as 66.73 ± 3.89 µg/mg GAE and 46.51 ± 0.96 µg/mg QE, respectively, in
R. brunonii
. The present study underlined the ethnomedicinal importance of
R. brunonii
and promised useful candidate for the search of newer and effective bioactive constituents.
The long history of using plant species as medicines worldwide provides clues for the search for bioactive phytochemicals. One of the important traditional medicinal plant species of Pakistan is
...Dryopteris ramosa
(Dryopteridaceae). The fronds of
Dryopteris ramosa
are traditionally used for the treatment of gastric ulcer and constipation. The crude methanol extract and aqueous fraction of
Dryopteris ramosa
exhibited strong free radical scavenging potential. Two xanthonoid compounds, mangiferin and isomangiferin, were isolated from the aqueous fraction of
Dryopteris ramosa
by chromatographic techniques (CC Sephadex LH20, followed by MPLC and purified by preparative TLC). Their structures were confirmed by spectroscopic analysis MS, NMR (1H, 13C, HSQC and HMBC). This is the first report on isolation of mangiferin and isomangiferin from Dryopteris genus though previously reported in other fern genera, e.g.,
Cystopteris
,
Acystopteris
,
Gymnocarpium
and
Asplenium
. The antioxidant potential of mangiferin (60.34 ± 0.14 μg/mL) and isomangiferin (55.98 ± 0.39 μg/mL) was comparable to ascorbic acid (57.97 ± 0.93 μg/mL), thus representing promising antioxidant agents against oxidative stress. The investigation of the mechanism of free radical scavenging by mangiferin and isomangiferin showed that the catechol moiety was involved in quenching of free radicals. This study justified the traditional use of
Dryopteris ramosa
confirming the pharmacological properties of isolated compounds. Further phytochemical studies on
Dryopteris ramosa
are needed for identification of new bioactive phytochemicals in this plant of ethnobotanical relevance.
In this article, ZnO:NiO:CuO nanocomposites (NCPs) were synthesized using a hydrothermal method, with different Zn : Ni : Cu molar ratios (1 : 1 : 1, 2 : 1 : 1, 1 : 2 : 1, and 1 : 1 : 1). The PXRD ...confirmed the formation of a NCP consisting of ZnO (hexagonal), NiO (cubic), and CuO (monoclinic) structures. The crystallite sizes of NCPs were calculated using Debye Scherrer and Williamson-Hall methods. The calculated crystalline sizes (Scherrer method) of the NCPs were determined to be 21, 27, 23, and 20 nm for the molar ratios 1 : 1 : 1, 2 : 1 : 1, 1 : 2 : 1, and 1 : 1 : 2, respectively. FTIR spectra confirmed the successful formation of heterojunction NCPs
via
the presence of metal-oxygen bonds. The UV-vis spectroscopy was used to calculate the bandgap of synthesized samples and was found in the range of 2.99-2.17 eV. SEM images showed the mixed morphology of NCPs
i.e.
, irregular spherical and rod-like structures. The dielectric properties, including AC conductivity, dielectric constant, impedance, and dielectric loss parameters were measured using an LCR meter. The DC electrical measurements revealed that NCPs have a high electrical conductivity. All the NCPs were evaluated for the photocatalytic degradation of Methylene blue (MB), methyl orange (MO), and a mixture of both of these dyes. The NCPs with a molar ratio 1 : 1 : 2 (Zn : Ni : Cu) displayed outstanding photocatalytic activity under sunlight, achieving the degradation efficiency of 98% for methylene blue (MB), 92% for methyl orange (MO) and more than 87% in the case of a mixture of dyes within just 90 minutes of illumination. The antibacterial activity results showed the more noxious nature of NCPs against Gram-negative bacteria with a maximum zone of inhibition revealed by the NCPs of molar ratio 1 : 2 : 1 (Zn : Ni : Cu). On the basis of these observations, it can be anticipated that the NCPs can be successfully employed for the purification of contaminated water by the degradation of hazardous organic compounds and in antibacterial ointments.
In this article, ZnO:NiO:CuO nanocomposites (NCPs) were synthesized using a hydrothermal method, with different Zn : Ni : Cu molar ratios (1 : 1 : 1, 2 : 1 : 1, 1 : 2 : 1, and 1 : 1 : 1).
Metallic nanoparticles have a substantial scientific interest because of their distinctive physicochemical and antimicrobial properties and the emergence of multidrug resistant pathogens could unlock ...the potential of nanoparticles to combat infectious diseases. The aim of the current study is to enhance the antibacterial potential of purified bacteriocin by combining bacteriocin and antibacterial silver nanoparticles (AgNPs). Hence, the interaction of natural antimicrobial compounds and antibacterial nanoparticles can be used as a potential tool for combating infectious diseases. In this study, a green, simple and effective approach is used to synthesize antibacterial AgNPs using fungal exopolysaccharide as both a reducing and stabilizing agent. The AgNPs were characterized by spectroscopic analysis, Scanning Electron Microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX) and Dynamic Light Scattering (DLS). Furthermore, the synergistic effect of bacteriocin-AgNPs was determined against pathogenic strains. The histogram of AgNPs indicated well-dispersed, stabilized and negatively charged particles with variable size distribution. The combination of bacteriocin with nanoparticles found to be more effective due to broad antibacterial potential with possibly lower doses. The current study is imperative to provide an alternative for the chemical synthesis of silver nanoparticles. It showed environmental friendly and cost effective green synthesis of antibacterial nanoparticles.
The employees' innovative behavior is a novel domain that has remained a topic of interest for many decades. Many researchers have found that a particular leadership style boosts the innovative ...behavior of employees in various contexts. However, prior research on the association between the dark side of leadership known as abusive supervision and innovative behavior revealed conflicting results. IT sector requires highly innovative employees, but the major problem faced by this sector is escalating competition and high workload, which may lead supervisors towards abusive supervision. Many theoretical models have been developed and tested, but the association of abusive supervision with employees' innovative behavior with intrinsic motivation and psychological safety as mediators has not been fully grasped in the IT sector of Pakistan. This study filled this gap and developed an explanatory model and tested the model by taking sample data from 98 respondents from IT organizations in Pakistan and applying PLS-based SEM for data analysis. The results revealed that abusive supervision is negatively associated with innovative behavior in this context. Moreover, abusive supervision is negatively associated with intrinsic motivation and psychological safety. Furthermore, intrinsic motivation and psychological safety are positively associated with innovative behavior. The results also demonstrated that the negative association of abusive supervision with innovative behavior is partially mediated by intrinsic motivation. However, psychological safety showed no mediating effect in this relationship. The results provide many theoretical and managerial implications.
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