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The addition of graphene nanoplatelets as a nanofiller on the surface of pristine and oxidized carbon fiber for making reinforced polymer composites has shown improvement in monotonic flexural properties. However, the fatigue response of these laminates under bending loads has not been investigated so far. The current study aims to examine the monotonic and fatigue behavior of the graphene nanoplatelets (GNPs) coated bi‐directional pristine and oxidized carbon fiber epoxy composites under bending loads. Eight layers of fabrics were used to manufacture the laminates through vacuum‐assisted resin transfer molding technique (VARTM). An optimum amount of GNP addition on oxidized fiber leads to ~830‐fold enhanced fatigue life at higher stresses as compared to pristine laminates. However, excessive GNP addition on pristine as well as oxidized fiber leads to a deterioration in fatigue life. In‐situ optical microscopic examination was done to observe the crack initiation and propagation of all the specimens with respect to the number of cycles coupled with post‐mortem SEM images of the fracture surfaces. [ABSTRACT FROM AUTHOR]

Endophytic bacteria reside within the plant cell and are beneficial to it in a number of ways like growth, protection to environmental conditions and sustainability in favor of the hosts. Throughout the ages, Garlic (Allium sativum L.) has legendary therapeutic importance. The important step in endophyte isolation is the removal of plant tissue surface microflora, called as surface sterilization. Endophytes from medicinal plants may mimic the compound produced by the host plant and also plays an important role in production of bioactive compound, so it is necessary to isolate endophytes, not the epiphytic microbes. The present investigation was undertaken with an aim to optimize the sterilization parameters viz: time and concentration of ethanol and sodium hypochlorite for isolation of endophytic bacteria as well as exploring their antibacterial activity from Allium sativum. The results revealed that concentration and exposure time of sterilizing agent caused prominent surface sterilization but have negative effect on isolation of endophytes. Experimental results revealed that 70% ethanol (6 min), 2% sodium hypochlorite (1 min) followed by 70% ethanol (30 sec) is effective for surface sterilization of leaf and 70% ethanol (6 min), 3% sodium hypochlorite (1 min) followed by ethanol (30 sec) for bulb of Allium sativum. A total of 86 bacterial endophytes were recovered and screened for antibacterial activity against Enterococcus faecalis, Bacillus cereus ATCC 11778, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Enterobacter, Klebsiella pneumoniae, Salmonella typhi and Proteus. Out of 86 bacterial endophytes, only (9%) endophytes were found to be inhibiting one or all test human pathogen. The findings of the present study suggest that use of optimized sterilization conditions are effective for removing surface bacterial strains without affecting endophytes as well as the Allium sativum plant of the Jaunpur district represents an excellent reservoir of endophytic bacteria and novel source of bioactive compounds. On the other hand different concentration and time of their exposure to different parts of plant is required for proper surface sterilization of that part and isolation of endophytes. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum is main causative agent behind the most destructive soil-borne plant disease, fusarium wilt, which damages economically significant food crops like bananas, sweet potatoes, tomatoes, legumes and melons. Traditionally, the disease is controlled by physical and chemical methods that affect the environment adversely. One of the ecofriendly approach of plant disease prevention is biological control. Plant growth promoting rhizobacteria and endophytes are now consider as promising agent for disease control. In the present study bulb of Allium sativum plant were used for isolation of endophytes and the endophytes were screened for their bio-control potential. Thirteen bacterial endophytes (ESS01, ESS02, ESS03, ESS06, ESS023, ESS024, ESS025, ESS072, ESS073, ESS074, ESS075, ESS076 and ESS077) exhibited antifungal activity against Fusarium oxysporum f. sp. ciceris. All the isolates inhibited more than 59% mycelial growth on dual-culture assay. However isolate ESS01 and ESS02 exhibited higher antifungal activity (74.81% & 71.48%) against the pathogen Fusarium oxysporum f. sp. ciceris. Only five endophytic isolates (ESS01, ESS02, ESS023, ESS076 & ESS077) out of thirteen endophytes were selected for the pot experiment because of having plant growth promoting attributes and inhibiting more than 70% mycelia growth of Fusarium oxysporum. Biocontrol technique of production of plant against harmful pathogen is now a promising approach for ecofriendly and sustainable agriculture. In this context endophytic isolates were analysed for their antifungal properties especially on Fusarium oxysporum. The endophytic isolates Bacillus aerius ESS02, Bacillus velezensis ESS076, and Bacillus siamensis ESS077 significantly enhanced the plant biomass in chick pea plant even in presence of pathogen and eliminating the harmful effect of Fusarium oxysporum on chick pea plant. Overall, present investigation indicate that Allium sativum harbors various endophytic bacteria that possess excellent antifungal activity and can be used as bio-control agent to control wilt disease of various plants. [ABSTRACT FROM AUTHOR]

An increasing number of traditional nanostructures are being replaced by self-assembled hierarchical nanostructures in terms of their electrochemical, optical, catalytic, and shielding properties. These morphologies exhibit high packing density, tunable porosity, and a large surface area. One of the most effective ways to stabilize hollow nanostructures is to modify the interfacial interactions and subsequent particle assembly that take place at the water-and-oil interface in inverse mini-emulsion. In this study, we present the formation of Ce1–xCuxO2 (0< x < 1.0) hollow structures, which show much higher electrochemical response than either of the end members, viz., CeO2 or CuO/Cu2O. It is established that by controlling the diffusion and reaction kinetics, the dimension of the hollow cavity can be easily tuned. The CeO2 nanostructures are exposed to different VOC gases, at several temperatures, and various concentrations ranging from 1 to 25 ppm. The best performance is found for formaldehyde (HCHO) detection at an activation temperature of 200 °C. Copper doping helps mitigate the poor conductivity issues associated with CeO2. This further opens more avenues for the application of Ce-based oxides in electrochemical devices. [ABSTRACT FROM AUTHOR]

The severe acute respiratory syndrome coronavirus 2 steady mutation lead to the desperate search for effective treatment and preventive measures for coronavirus disease-2019 (COVID-19) globally. Ayurveda describes various medications that have been recognized for their pharmacological properties, particularly immunomodulation and anti-viral properties. Objective: The objective of this study was comparative assessment of Guduchi Ghana Vati and Sudarshana Ghana Vati intake for the prophylaxis of COVID-19, with a control arm of standard prophylactic care in a population in a containment zone. Materials and methods: Communities having at least one confirmed case of COVID-19 were identified in 19 districts of India in 14 states. Twenty thousand healthy participants, irrespective of gender, in the intervention group and 10,000 healthy participantsin the control group were enrolled from these selected communities through the Central Council for Research in Ayurvedic Sciences identified 15 institutes. Two tablets (250 mg each) of Guduchi Ghana Vati were given twice daily with warm water after food or two tablets (500 mg each) of Sudarshana Ghana Vati were given twice daily with warm water after food for 30 days in the intervention group and standard of care issued by central/state/local health authorities as part of standard preventive measure against COVID-19 was followed in the control group. The primary outcome measure of the study was the comparative assessment of the occurrence of COVID-19 infection in clinically stable participants in the community having at least one confirmed case already identified with the control arm of standard prophylactic care. The secondary outcome measures were a comparative assessment of the severity of COVID-19 infection in participants taking Guduchi Ghana Vati or Sudarshana Ghana Vati and the control arm by assessment of participants not requiring hospitalization, the severity of symptoms of hospitalized patients in wards and patients requiring intensive care unit admission/ventilator support, global assessment of overall change as per the investigator and safety assessment by the evaluation of occurrence of adverse event (AE)/serious AE (SAE) due to consumption of Ayurvedic intervention. A P value of < 0.05 was considered as significant. Results: The rate of COVID-19 positivity in the intervention group was 0.07% (n = 14) and in the control group was 0.04% (n = 4).Among 14 participantsin the intervention group who tested COVID-19 positive, only one participant required hospitalization for management of COVID-19. The 4 participants who tested COVID-19 positive in the control group were hospitalized for management of COVID-19. After 30 days of intervention, the mean Immune Status Questionnaire (ISQ) score in the intervention group at baseline was 8.50, which increased to 9.16 on the 30th day (mean difference = 0.66), depicting the better immune status of the participants. Whereas, in the control group, the mean ISQ score at baseline was 8.68, which after 30 days reached 8.91 (mean difference = 0.23). No adverse drug reactions were reported in the study. Conclusion: Guduchi Ghana Vati and Sudarshana Ghana Vati were well tolerated and safe and showed potential benefits in the prophylaxis of COVID-19 in the participants. The study population is limited in representing people affected by COVID-19. Subsequent randomized controlled clinical research on diverse population may be undertaken to substantiate the prophylactic role of trial drugs in varied population. [ABSTRACT FROM AUTHOR]