Design of XS2 (X = W or Mo)-Decorated VS2 Hybrid Nano-Architectures with Abundant Active Edge Sites for High-Rate Asymmetric Supercapacitors and Hydrogen Evolution Reactions

Two-dimensional layered transition metal dichalcogenides have emerged as promising materials for supercapacitors and hydrogen evolution reaction (HER) applications. Herein, the molybdenum sulfide (MoS₂ )@vanadium sulfide (VS₂ ) and tungsten sulfide (WS₂ )@VS₂  hybrid nano-architectures prepared via a facile one-step hydrothermal approach is reported. Hierarchical hybrids lead to rich exposed active edge sites, tuned porous nanopetals-decorated morphologies, and high intrinsic activity owing to the strong interfacial interaction between the two materials. Fabricated supercapacitors using MoS₂ @VS₂  and WS₂ @VS₂  electrodes exhibit high specific capacitances of 513 and 615 F g^{- 1} , respectively, at an applied current of 2.5 A g^{- 1}  by the three-electrode configuration. The asymmetric device fabricated using WS₂ @VS₂  electrode exhibits a high specific capacitance of 222 F g^{- 1}  at an applied current of 2.5 A g^{- 1}  with the specific energy of 52 Wh kg^{- 1}  at a specific power of 1 kW kg^{- 1} . For HER, the WS₂ @VS₂  catalyst shows noble characteristics with an overpotential of 56 mV to yield 10 mA cm^{- 2} , a Tafel slope of 39 mV dec^-1 , and an exchange current density of 1.73 mA cm^{- 2} . In addition, density functional theory calculations are used to evaluate the durable heterostructure formation and adsorption of hydrogen atom on the various accessible sites of MoS₂ @VS₂  and WS₂ @VS₂  heterostructures.

Decontamination and Reuse of N95 Masks: A Narrative Review

BACKGROUND

The COVID-19 pandemic has presented an unprecedented strain on healthcare supplies. Currently there is a global shortage of personal protective equipment (PPE), especially N95 masks. In order to safeguard healthcare personnel in this critical time and to mitigate shortages of N95 respirators, reuse of N95 respirators has to be considered.

METHODS

Using PubMed and Science Direct, a literature search was conducted to find and synthesize relevant literature on decontamination of N95 respirators for their subsequent reuse. Peer-reviewed publications related to methods of decontamination from January 2007 to April 2020 in the English language are included in this narrative review. Bibliographies of articles for relevant literature were also scrutinized. Findings. A total of 19 studies are included in this narrative review. The appraised methods include ultraviolet germicidal irradiation (UVGI), moist heat incubation (MHI), ethylene oxide (EtO), hydrogen peroxide vapor (HPV), microwave steam bags (MSB), microwave-generated steam (MGS), dry microwave oven irradiation, hydrogen peroxide gas plasma (HPGP), dry heat, liquid hydrogen peroxide, and bleach and alcohol.

CONCLUSION

In light of the COVID-19 pandemic, reuse of N95 respirators, although suboptimal, can be considered. Evidence reveals that UVGI, MHI, and HPV are amongst the safest and efficacious methods for decontamination of N95 masks. More research is needed to establish the safety and effectiveness of MGS, MSB, dry heat, EtO, liquid hydrogen peroxide, and HPGP. Alcohol, microwave irradiation, and bleach are not recommended because they damage N95 respirators.

Knowledge and practices of critical care health professionals related to ventilator associated pneumonia in tertiary care hospitals of Islamabad and Rawalpindi

OBJECTIVE

To assess knowledge and practices of critical care health professionals related to ventilator associated pneumonia.

METHODS

This cross-sectional survey was conducted at eight tertiary care public and private hospitals of Islamabad/Rawalpindi, Pakistan, from September 2015 to March 2016, and comprised healthcare professionals. Stratified random sampling was used. Data was collected using close-ended validated questionnaire. SPSS 22 was used for data analysis.

RESULTS

Of the 153 participants, 45(29.4%) were doctors, 91(59.4%) were nurses and 17(11.1%) were respiratory therapists. The overall mean age was 31±8.14 years. The overall mean knowledge and practice scores regarding prevention of ventilator-associated pneumonia were 11.14±3.12 and 8.83±1.53, respectively. The mean knowledge score was 11.77±3.84 for physicians, 10.84± 2.91 for nurses and 10.82±1.94 for respiratory therapists. However, the best practice scores were seen in the respiratory therapists 9.64±0.78 (p=0.008).

CONCLUSIONS

The majority of the participants had adequate knowledge and even better practices, particularly respiratory therapists.

Recent Progress for the Utilization of Curcuma longa, Piper nigrum and Phoenix dactylifera Seeds against Type 2 Diabetes

Background

Diabetes mellitus is an important human disease afflicting many from various walks of life in different countries. Even though modern medicines contribute a variety of effective treatment options, they can have several unfavourable effects. The intention of this review is to organize and discuss various studies that have been previously conducted on the effectiveness of these herbal plants in diabetes.

Method

By using various electronic search databases, a comprehensive English literature search was conducted. Different search terms were used by combining all the search fields in titles, abstracts and keywords.

Results

Curcuma longa,a spice, is commonly known as turmeric and belongs to the family Zingiberaceae. Piper nigrumis also a spice, commonly called black pepper, and belongs to the family Piperaceae. Phoenix dactylifera, commonly known as date fruit, belongs to the family Arecaceae. From ancient times, they have been traditionally used for the treatment of various diseases. Among various activities, regulation of hyperglycaemia is considered one of their important effects. One of the aetiological factors implicated in the development of diabetes and its complications is the damage induced by free radicals. Antioxidant properties of antidiabetic compounds would be more beneficial. Extracts of these plants have shown hypoglycaemic and hypolipidaemic effects by the involvement of several mechanisms. In the future, further studies are needed to investigate the mechanisms involved in their hypoglycaemic potential and their active constituents as synthetic analogues.

Conclusions

This review focusses on some medicinal plants that have antidiabetic effect, thus contributing to the reduction of risk factors associated with diabetes, and related beneficial effects are compiled.

Effect of inorganic nitrogenous fertilizer on productivity of recently reclaimed saline sodic soils with and without biofertilizer

Saline sodic soils after reclamation become infertile due to leaching of most of the nutrients along with salts from the rooting medium. Microbes can play a vital role in the productivity improvement of such soils. In this study a saline sodic field having EC, 6.5 dS m(-1), pH, 9.1 and gypsum requirement (GR) 3.5 tons acre(-1) was reclaimed by applying gypsum at the rate of 100% GR. Rice and wheat crops were transplanted/sown for three consecutive years. Inorganic nitrogenous fertilizer was used with and without biofertilizers i.e., Biopower (Azospirillum) for rice and diazotroph inoculums for wheat. Nitrogen was applied at the rate of 0, 75% of recommended dose (RD), RD, 125% of RD and 150% of RD. Recommended dose of P without K was applied to all the plots. Biopower significantly improved Paddy and straw yield of rice over inorganic nitrogenous fertilizer. In case of wheat diazotroph inoculum improved grain and straw yield significantly over inorganic nitrogenous fertilizer. Among N fertilizer rates, RD + 25% additional N fertilizer was found to be the best dose for rice and wheat production in recently reclaimed soils. Nitrogen concentration and its uptake by paddy, grain and straw were also increased by biopower and diazotroph inoculum over inorganic nitrogenous fertilizer. Among N fertilizer rates, RD + 25% additional N fertilizer was found to be the best dose for nitrogen concentration and its uptake by paddy, grain and straw. Total soil N, available P and extractable K were increased while salinity/sodicity parameters were decreased with the passage of time. The productivity of the soil was improved more by biofertilizers over inorganic N fertilizers.

Resistance of some cultivated Brassicaceae to infestations by Plutella xylostella (Lepidoptera: Plutellidae)

Selecting insect-resistant plant varieties is a key component of integrated management programs of oligophagous pests such as diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), but rigorous research on important life history parameters of P. xylostella in relation to host plant resistance is rare. We evaluated six conventional brassicaceous species, namely, Brassica napus L. 'Q2', B. rapa L., B. juncea (L.) Czern., B. carinata L., B. oleracea L., and Sinapis alba L., and two herbicide-tolerant cultivars, namely, B. napus 'Liberty' and B. napus 'Conquest' for their resistance against P. xylostella. Brassicaceae species and cultivars varied considerably in their susceptibilities as hosts for P. xylostella. Sinapis alba and B. rapa plants were highly preferred by ovipositing females and trichome density on adaxial and abaxial leaf surfaces had nonsignificant effects on P. xylostella oviposition. Larval survival was similar on the genotypes we tested, but host plants significantly affected larval and pupal developmental time, herbivory, pupal weight, silk weight, adult body weight, forewing area and longevity (without food) of both male and female P. xylostella. Larval and pupal development of females was fastest on B. juncea and S. alba, respectively. Specimens reared on B. napus Liberty and B. oleracea, respectively, produced the lightest female and male pupae. Defoliation by both female and male larvae was highest on B. rapa, whereas least herbivory occurred on S. alba. Females reared on S. alba were heavier and lived longer in the absence of food than their counterparts raised on other tested host plants. Brassica oleracea could not compensate for larval feeding to the level of the other species we evaluated. B. napus Conquest, B. napus Q2, B. carinata, B. rapa, and S. alba produced, respectively, 1.6-, 1.8-, 1.8-, 3.9-, and 5.5-fold heavier root systems when infested than their uninfested counterparts, suggesting that these species were better able to tolerate P. xylostella infestations.