Copper oxide and Zinc (Zn)-doped Copper oxide nanostructures (CuO-NSs) are successfully synthesized by using a hydrothermal technique. The as-obtained pure and Zn-doped CuO-NSs were tested to study ...the effect of doping in CuO on structural, optical, and antibacterial properties. The band gap of the nanostructures is calculated by using the Tauc plot. Our results have shown that the band gap of CuO reduces with the addition of Zinc. Optimization of processing conditions and concentration of precursors leads to the formation of pine needles and sea urchin-like nanostructures. The antibacterial properties of obtained Zn-doped CuO-NSs are observed against Gram-negative
and Gram-positive
bacteria via the agar well diffusion method. Zn doped s are found to have more effective bacterial resistance than pure CuO. The improved antibacterial activity is attributed to the reactive oxygen species (ROS) generation.
In this work, we report the preparation of TiO2 and Co-S doped TiO2 nanostructures by sol–gel and wet impregnation method for their potential applications in photocatalytic processes for ...environmental applications in water purification to degrade pollutant dyes. The crystalline phase, morphology, optical properties, and chemical composition of the synthesized nanoparticles (NPs) are studied by using X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), UV–Visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR). The photocatalytic accomplishment of synthesized nanostructures is observed for the degradation of brilliant green (BG). All the synthesized nanostructures exhibited excellent photodegradation activity. The observed rate of degradation of dye is higher with the Co-S doped TiO2 nanostructures than pure TiO2.
Due to increase in infectious diseases, researchers are trying to synthesize effective, less toxic and inexpensive antimicrobial agents. For this, silver nanoparticles have been proved as potential ...antimicrobial agents. Therefore, in the present study, a supramolecular compound (calix4arene)-based silver nanoparticles (Calix–AgNPs (
4
)) were synthesized and applied as an efferent antimicrobial agent. The characterization of Calix–AgNPs was performed by UV–Vis, FTIR, SEM, XRD and Zetasizer techniques. Relative antimicrobial activity for synthesized calix4arene derivative (
3
) and Calix-AgNPs was explored against two types of bacteria (G + ve
S. areus, and
G – ve
E.coli)
and a fungal strain
(R. stolonifer
) using solution of silver nitrate salt as a reference. For antimicrobial study, five different dilutions of each compound derivative and Calix-AgNPs were prepared in acetonitrile (ACN) and deionized (DI) water, respectively. From results, it was revealed that Calix-AgNPs are efficient antimicrobial agents as compared to calix4arene derivative and silver salt. The minimum inhibitory value (MIC) was observed at 0.62 μg/mL against selected microorganisms for Calix-AgNPs.
Graphical abstract
Water pollution caused by the release of organic pollutants is a major environmental concern worldwide. These pollutants can have harmful effects on aquatic ecosystems and the organisms living within ...them, as well as on human health when contaminated water is consumed. It is essential to implement proper treatment and management strategies to prevent and mitigate water pollution. Moreover, the major untreated industrial effluents are synthetic organic compounds especially 2,4,6-trichlorophenol (TCP) which cause several environmental issues and heath related problems in humans. To cope with this problem, an excellent 2D porous material based on p-DMAC4/GO composite has been synthesized as adsorbent material for the effective removal of 2,4,6-trichlorophenol pollutant from wastewater. In this regard, the advanced analytical tools such as Fourier-Transform infrared (FT-IR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray spectroscopy (EDS) were used for its characterization. The results justified the chemical composition, excellent crystalline nature, surface morphology and elemental composition of the synthesized composite material. The synthesized adsorbent material showed 95% adsorption of TCP from wastewater system at optimal conditions i.e., pH (6), adsorbent dosage (30 mg) and shaking time (60 min). The mathematical models such as isotherms, thermodynamics and kinetics studies validate the nature of adsorption process of TCP pollutant. The adsorption data found to be best fitted with Langmuir isotherms (R2 = 0.99); whereas kinetic study suggested the pseudo-second-order nature of reaction with R2 = 0.99. The thermodynamics study confirmed the spontaneous and endothermic nature of the TCP pollutant onto the surface of p-DMAC4/GO material. Moreover, the results of current work were also compared with existing reported adsorbents and data suggested the higher efficiency, feasibility, and reusability of p-DMAC4/GO material to remove the TCP pollutant from the wastewater system.
Neurada procumbens Linn. possesses a wide range of phytochemical and bioactive entities such as flavonoids and polyphenols that decrease the oxidative stress and enhance synaptic plasticity, ...resulting in accelerated healing processes. Almost all parts of the plant have been used in the traditional system of medicine for various disorders including its use as an anticonvulsant, sexual tonic, and anti-rheumatic agent. This study is designed to evaluate the anxiolytic and antidepressant activities of the methanolic crude extract of N. procumbens (Np.Cr) based on its use in traditional medicine and presence of the phytochemical constituents. Aqueous methanolic extract of Np.Cr was prepared under reduced pressure using rotary evaporator, and different chemical constituents were identified by phytochemical screening. Light/dark exploration, elevated plus maze (EPM), and hole board tests were used to assess the anxiolytic activity, while forced swim and tail suspension tests were used to assess the antidepressant potential of the crude extract. Treatment groups treated individually with 3 different doses; i.e., 50, 100, and 200 mg/kg of Np.Cr, showed a dose-dependent increase in time spent in light compartment and in open arms as well as increased number of head poking by the experimental animals. Np.Cr showed significant antidepressant potential (P < .05) as evident from marked decrease in behavioral despair. Findings of the present study assure that N. procumbens possess significant anxiolytic and antidepressant potential with the demands of further investigations to identify the active compound(s) responsible for these pharmacological effects.
Graphical Abstract
The results of meta‐analyses investigating the role of folate on depression are conflicting. The aim of this umbrella meta‐analysis was to obtain an overall effect and give a concise and resolving ...conclusion. International scientific databases including PubMed, Scopus, and Web of Science were searched up to Oct 2023. All observational and interventional meta‐analyses investigating the role of folate in depression were included in the study. Random‐effects model was employed to obtain pooled results. I2 statistics and Cochrane Q test were used to assess the between‐study heterogeneity. The quality of included meta‐analyses was evaluated using the Assessing the Methodological Quality of Systematic Reviews 2 (AMSTAR2) questionnaire. Overall 11 studies were included, of which 8 studies went under quantitative evaluation. The results indicated that folate supplementation significantly relieved depression symptoms (SMD: −0.42; 95% CI: −0.57, −0.27, p < .001; I2 = 0.0%, p‐heterogeneity = 0.554) (WMD: −3.20; 95% CI: −4.00, −2.41, p < .001, I2 = 14.8%, p‐heterogeneity = 0.318) with low levels of heterogeneity. Also, based on observational studies, folate insufficiency significantly increased the odds ratio of depression by 35% (OR:1.35; 95% CI: 1.27, 1.42, p < .001, I2 = 8.7%, p‐heterogeneity = 0.350). The findings support the fact that folate supplementation could be suggested as an efficacious and adjuvant agent in the alleviation of depression symptoms along with routine medications.
Folate supplementation significantly decreased symptoms of depression. The decreasing effect is more robust when supplementation lasts for >10 weeks. Low serum level of folate is significantly associated with odds of depression.
Purpose
The purpose of the paper is to investigate co-movement of major implied volatility indices and economic policy uncertainty (EPU) indices with both the health-based fear index and market-based ...fear index of COVID-19 for the USA and the UK to help investors and portfolio managers in their informed investment decisions during times of infectious disease spread.
Design/methodology/approach
This study uses wavelet coherence approach because it allows to observe lead–lag nonlinear relationship between two time-series variables and captures the heterogeneous perceptions of investors across time and frequency. The daily data used in this study about the USA and the UK covers major implied volatility indices, EPU, health-based fear index and market-based fear index of COVID-19 for both the first and second waves of COVID-19 pandemic over the period from March 3, 2020 to February 12, 2021.
Findings
The results document a strong positive co-movement between implied volatility indices and two proxies of the COVID-19 fear. However, in all the cases, the infectious disease equity market volatility index (IDEMVI), the COVID-19 proxy, is more representative of the stock market and exhibits a stronger positive co-movement with volatility indices than the COVID-19 fear index (C19FI). This study also finds that the UK’s implied volatility index weakly co-moves with the C19FI compared to the USA. The results show that EPU indices of both the USA and the UK exhibit a weak or no correlation with the C19FI. However, this study finds a significant and positive co-movement of EPU indices with IDEMVI over the short horizon and most of the sampling period with the leading effect of IDEMVI. This study’s robustness analysis using partial wavelet coherence provides further strengths to the findings.
Research limitations/implications
The investment decisions and risk management of investors and portfolio managers in financial markets are affected by the new information on volatility and EPU. The findings provide insights to equity investors and portfolio managers to improve their risk management practices by incorporating how health-related risks such as COVID-19 pandemic can contribute to the market volatility and economic risks. The results are beneficial for long-term equity investors, as their investments are affected by contributing factors to the volatility in US and UK’s stock markets.
Originality/value
This study adds following promising values to the existing literature. First, the results complement the existing literature (Rubbaniy et al., 2021c) in documenting that type of COVID-19 proxy matters in explaining the volatility (EPU) relationships in financial markets, where market perceived fear of COVID-19 is appeared to be more pronounced than health-based fear of COVID-19. Second, the use of wavelet coherence approach allows us to observe lead–lag relationship between the selected variables, which captures the heterogeneous perceptions of investors across time and frequency and have important insights for the investors and portfolio managers. Finally, this study uses the improved data of COVID-19, stock market volatility and EPU compared to the existing studies (Sharif et al., 2020), which are too early to capture the effects of exponential spread of COVID-19 in the USA and the UK after March 2020.
Teratogenic and embryotoxic effect of diclofenac sodium (DS) on different developmental stages of the chick-embryos was investigated by examining different parameters such as its mortality rate, ...hatching, morphological measurements, weighing its internal organs and calculation of different indices. Experiment was divided into four trials with different dose (0.1 mL, 0.2 mL, 0.3 mL in groups A, B, and C, respectively and group D received 0.3 mL saline solution (0.9% NaCl) and group E remained un-injected) administration and observation. Results of first and second trial showed statistically (p<0.01) significant difference in bodyweight, body-length, forelimb and hindlimb length between experimental and control groups. In third trial, diclofenac sodium administration showed a statistically (p<0.01) significant difference in the bodyweight, body-length, forelimb, hindlimb length, liver weight, egg weight (EE ratio) and kidney somatic index (KSI). The beak-size, heart weight, kidney weight, cardiac somatic index (CSI) and hepato somatic index (HSI) were not significant (p>0.05) when compared with the control groups. In trial 4, forelimb, hindlimb length, heart weight, CSI and HSI were statistically (p<0.01) significant. Body-length and liver weight were significant (p<0.05). While bodyweight, beak size, kidney weight and KSI were non-significant (p>0.05). The mortality rate was increased with increase dose of DS and also affected the hatching. DS effect on chick embryos can be applied to humans because the early development of mammals and birds are closely related. So, it was concluded that DS should be used with caution during pregnancy especially during first trimester of pregnancy.
Display omitted
•Teratogenic and embryonic effect of diclofenac sodium on different development stages of chick embryo was investigated.•Results of first and second trial showed statistically (p<0.01) significant difference in bodyweight, body-length, forelimb and hindlimb length.•In third trial, DS administration showed a statistically (p<0.01) significant difference in the bodyweight, body-length, forelimb, hindlimb length, liver weight, EE ratio and KSI.•It was concluded that DS should be used with caution during pregnancy.
Renewable energy can be harnessed from wastewater, whether from municipalities or industries, but this potential is often ignored. The world generates over 900 km3 of wastewater annually, which is ...typically treated through energy-consuming processes, despite its potential for energy production. Environmental pollution is a most important and serious issue for all and their adulterations to the aquatic system are very toxic in very low concentrations. Photocatalysis is a prominent approach to eliminating risky elements from the environment. The present study developed Zinc oxide (ZnO), Copper-doped Zinc oxide (CuZnO), and Cobalt-doped Zinc oxide (CoZnO) nanostructures (NSs) by facile hydrothermal route. The crystalline and structural stability of the synthesized nanostructures were evident from XRD and FESEM analysis. Metal, and oxygen bond and their interaction on the surfaces and their valency were explored from XPS spectra. Optical orientations and electron movements were revealed from UV-Visible analysis. After 100 min exposure time with 1 g of catalyst concentration 60%, 70%, and 89% of dye degraded, for dye concentration (5 mg/L to 50 mg/L), the huge variation observed (70% to 22%), (80% to 16%), (94% to 10%). The highest photodegradation rate (55%, 75%, 90%) was observed on pH~12 using ZnO, CoZnO, and CuZnO respectively. Photodegradation of methylene blue confirmed the largest surface area, rate of recombination, photo-excited charge carriers, photo-sensitivity range, and radical generations of ZnO, CuZnO, and CoZnO. The present study, therefore, suggested that CuZnO would be preferred to produce nanomaterials for industrial wastewater treatment like methylene.
An environmentally safe, efficient, and economical microwave-assisted technique was selected for the production of silver nanoparticles (AgNPs). To prepare uniformly disseminated AgNPs, xanthan gum ...(XG) was utilized as both a reducing and capping agent. UV–Vis spectroscopy was used to characterize the formed XG-AgNPs, with the absorption band regulated at 414 nm under optimized parameters. Atomic force microscopy was used to reveal the size and shape of XG-AgNPs. The interactions between the XG capping agent and AgNPs observed using Fourier transform infrared spectroscopy. The XG-AgNPs were placed in between glassy carbon electrode and Nafion® surfaces and then deployed as sensors for voltammetric evaluation of mercury ions (Hg2+) using square-wave voltammetry as an analytical mode. Required Nafion® quantities, electrode behavior, electrolyte characteristics, pH, initial potentials, accumulation potentials, and accumulation durations were all comprehensively investigated. In addition, an electrochemical mechanism for the oxidation of Hg2+ was postulated. With an exceptional limit of detection of 0.18 ppb and an R2 value of 0.981, the sensors’ measured linear response range was 0.0007–0.002 µM Hg2+. Hg2+ evaluations were ultimately unaffected by the presence of many coexisting metal ions (Cd2+, Pb2+, Cr2O4, Co2+,Cu2+, CuSO4). Spiked water samples were tested using the described approach, with Hg2+ recoveries ranging from 97% to 100%.
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