An ion-selective chemiresistive platform as demonstrated for the detection of nitrogen species in water.

The use of ion-selective electrodes (ISE) is a well-established technique for the detection of ions in aqueous solutions but requires the use of a reference electrode. Here, we introduce a platform of ion-selective chemiresistors for the detection of nitrogen species in water as an alternative method without the need for reference electrodes. Chemiresistors have a sensitive surface that is prone to damage during operation in aqueous solutions. By applying a layer of ion-selective membrane to the surface of the chemiresistive device, the surface becomes protected and highly selective. We demonstrate both anion-selective (NO3-, NO2-) and cation-selective (NH4+) membranes. The nitrate sensors are able to measure nitrate ions in a range of 2.2-220 ppm with a detection limit of 0.3 ppm. The nitrite sensors respond between 67 ppb and 67 ppm of nitrite ions (64 ppb detection limit). The ammonium sensors can measure ammonium concentrations in a wide range from 10 ppb to 100 ppm (0.5 ppb detection limit). The fast responses to nitrate and nitrite are due to a mechanism involving electrostatic gating repulsion between negative charge carriers of the film and anions while ammonium detection arises from two mechanisms based on electrostatic gating repulsion and adsorption of ammonium ions at the surface of the p-doped chemiresistive film. The adsorption phenomenon slows down the recovery time of the ammonium sensor. This sensor design is a new platform to continuously monitor ions in industrial, domestic, and environmental water resources by robust chemiresistive devices.

A reagent-free phosphate chemiresistive sensor using carbon nanotubes functionalized with crystal violet.

Phosphate is important for plant and animal growth. Therefore, it is commonly added as a fertilizer in agricultural fields. Phosphorus is typically measured using colorimetric or electrochemical sensors. Colorimetric sensors suffer from a limited measuring range and toxic waste generation while electrochemical sensors suffer from long-term drifts due to reference electrodes. Here, we propose a solid-state, reagent-free and reference electrode-free chemiresistive sensor for measuring phosphate using single-walled carbon nanotubes functionalized with crystal violet. The functionalized sensor exhibited a measuring range from 0.1 mM to 10 mM at pH 8. No significant interference was observed for common interfering anions like nitrates, sulphates, and chlorides. This study showed a proof-of-concept chemiresistive sensor, which can potentially be used to measure phosphate levels in hydroponics and aquaponics systems. The dynamic measuring range further needs to be extended for surface water samples.

Implementation of multiparametric magnetic resonance imaging technology for evaluation of patients with suspicion for prostate cancer in the clinical practice setting.

OBJECTIVES: To investigate the impact of implementing magnetic resonance imaging (MRI) and ultrasonography fusion technology on biopsy and prostate cancer (PCa) detection rates in men presenting with clinical suspicion for PCa in the clinical practice setting. PATIENTS AND METHODS: We performed a review of 1 808 consecutive men referred for elevated prostate-specific antigen (PSA) level between 2011 and 2014. The study population was divided into two groups based on whether MRI was used as a risk stratification tool. Univariable and multivariable analyses of biopsy rates and overall and clinically significant PCa detection rates between groups were performed. RESULTS: The MRI and PSA-only groups consisted of 1 020 and 788 patients, respectively. A total of 465 patients (45.6%) in the MRI group and 442 (56.1%) in the PSA-only group underwent biopsy, corresponding to an 18.7% decrease in the proportion of patients receiving biopsy in the MRI group (P < 0.001). Overall PCa (56.8% vs 40.7%; P < 0.001) and clinically significant PCa detection (47.3% vs 31.0%; P < 0.001) was significantly higher in the MRI vs the PSA-only group. In logistic regression analyses, the odds of overall PCa detection (odds ratio [OR] 1.74, 95% confidence interval [CI] 1.29-2.35; P < 0.001) and clinically significant PCa detection (OR 2.04, 95% CI 1.48-2.80; P < 0.001) were higher in the MRI than in the PSA-only group after adjusting for clinically relevant PCa variables. CONCLUSION: Among men presenting with clinical suspicion for PCa, addition of MRI increases detection of clinically significant cancers while reducing prostate biopsy rates when implemented in a clinical practice setting.

Partial Nephrectomy is Associated with Higher Risk of Relapse Compared with Radical Nephrectomy for Clinical Stage T1 Renal Cell Carcinoma Pathologically Up Staged to T3a.

PURPOSE: We studied recurrence-free survival after partial vs radical nephrectomy for clinical stage T1 renal cell carcinoma in all patients and in those up staged to pathological stage T3a. MATERIALS AND METHODS: We retrospectively reviewed the records of 1,250 patients who underwent partial or radical nephrectomy for clinically localized T1 renal cell carcinoma between 2006 and 2014. Recurrence-free survival was estimated using the Kaplan-Meier method and evaluated as a function of nephrectomy type with the log rank test and Cox models, adjusting for clinical, radiological and pathological characteristics. RESULTS: A total of 86 recurrences (7%) were observed during a median followup of 37 months. No difference in recurrence-free survival between partial and radical nephrectomy was found among all clinical stage T1 renal cell carcinomas. T3a up staging was noted in 140 patients (11%) and recurrent disease was observed in 44 (31.4%) during a median followup of 38 months. Among up staged T3a cases partial nephrectomy was associated with shorter recurrence-free survival compared to radical nephrectomy on univariable analysis (recurrence HR 2.04, 95% CI 1.12-3.68, p = 0.019) and multivariable analysis (recurrence HR 5.39, 95% CI 1.94-14.9, p = 0.001). CONCLUSIONS: In a subgroup of patients clinically staged T1 renal cell carcinoma will be pathologically up staged to T3a. Among these patients those who undergo partial nephrectomy appear to have inferior recurrence-free survival relative to those who undergo radical nephrectomy.

Active surveillance for incidental renal mass in the octogenarian.

OBJECTIVE: To evaluate the oncologic outcomes among a large cohort of octogenarian patients placed on active surveillance for a localized renal mass. METHODS: We retrospectively reviewed patients ≥80 years of age presenting for asymptomatic, incidentally detected clinically localized stage T1 renal mass between 2006 and 2013 who were followed by active surveillance (AS). The primary endpoint was development of metastatic renal cell carcinoma. Secondary outcomes included intervention-free survival, cancer-specific survival, and overall survival. RESULTS: Eighty-nine octogenarians (median age = 83.4 years) were placed on AS for a median 29.9 months. Median Charlson Comorbidity Index and Katz Index of Independence in Activities of Daily Living scores were 2 and 5, respectively. For all comers, median initial tumor size was 2.4 cm with median growth rate of 0.20 cm/year. Eight (9.0%) patients failed AS due to delayed intervention and three (1.1%) due to systemic progression after median follow-up of 27.8 and 39.9 months, respectively. Two (2.2%) patients in the delayed intervention cohort developed metastasis after treatment. Tumor growth rate was significantly higher among those undergoing intervention versus no intervention (0.60 vs. 0.15 cm/year, P = 0.05) and among patients with systemic progression versus no metastasis (1.28 vs. 0.18 cm/year, P = 0.001). Five-year intervention-free, metastasis-free, cancer-specific, and overall survivals were 90.6, 95.6, 95.6, and 85.7%, respectively. CONCLUSION: AS represents an effective management strategy in octogenarians given low overall risk of metastasis. Tumor growth kinetics may identify patients at risk of systemic progression in whom treatment should be considered.

Positive Surgical Margins Increase Risk of Recurrence after Partial Nephrectomy for High Risk Renal Tumors.

PURPOSE: The clinical significance of a positive surgical margin after partial nephrectomy remains controversial. The association between positive margin and risk of disease recurrence in patients with clinically localized renal neoplasms undergoing partial nephrectomy was evaluated. MATERIALS AND METHODS: A retrospective multi-institutional review of 1,240 patients undergoing partial nephrectomy for clinically localized renal cell carcinoma between 2006 and 2013 was performed. Recurrence-free survival was estimated using the Kaplan-Meier method and evaluated as a function of positive surgical margin with the log rank test and Cox models adjusting for tumor size, grade, histology, pathological stage, focality and laterality. The relationship between positive margin and risk of relapse was evaluated independently for pathological high risk (pT2-3a or Fuhrman grades III-IV) and low risk (pT1 and Fuhrman grades I-II) groups. RESULTS: A positive surgical margin was encountered in 97 (7.8%) patients. Recurrence developed in 69 (5.6%) patients during a median followup of 33 months, including 37 (10.3%) with high risk disease (eg pT2-pT3a or Fuhrman grade III-IV). A positive margin was associated with an increased risk of relapse on multivariable analysis (HR 2.08, 95% CI 1.09-3.97, p=0.03) but not with site of recurrence. In a stratified analysis based on pathological features, a positive surgical margin was significantly associated with a higher risk of recurrence in cases considered high risk (HR 7.48, 95% CI 2.75-20.34, p <0.001) but not low risk (HR 0.62, 95% CI 0.08-4.75, p=0.647). CONCLUSIONS: Positive surgical margins after partial nephrectomy increase the risk of disease recurrence, primarily in patients with adverse pathological features.

Distribution of tension wood like gelatinous fibres in the roots of Acacia nilotica (Lam.) Willd.

KEY MESSAGE: The present study unravels the anatomical characteristics and distribution patterns of cell wall polymers in the G-fibres found in the roots of A. nilotica using different microscopy techniques (light, electron and immunofluorescence microscopy). The present study was aimed to investigate the anatomy of reaction xylem in the positively gravitropic roots of Acacia nilotica growing in compact and waterlogged soils. The roots collected from the two different sites showed occurrence of gelatinous fibres throughout xylem radii from a distance of 4 cm from the soil surface. The thickness of gelatinous layer (G-layer) increased in the root collected from the deeper soil. Further, the ultrastructural studies revealed a complete replacement of S2 and S3 layers in G-fibres nearer to root tip region as compared to the root portion close to upper part of the soil surface. In addition, these fibres demonstrated intense lignification in compound middle lamellae region of G-fibre walls. Moreover, the vessel density and their width increased considerably near the root tip region. The immunofluorescence analysis suggested that the ß-1,4-galactans were prevalent in G-layer, whereas the xylan was restricted to only regions of lignified secondary wall. The similarities in distribution pattern and anatomical features of G-fibres in waterlogged and non-waterlogged roots suggest the occurrence of G-fibres as inherent characteristics in the roots of Acacia nilotica.

Outcomes 5 years after response to rituximab therapy in children and adults with immune thrombocytopenia.

Treatments for immune thrombocytopenic purpura (ITP) providing durable platelet responses without continued dosing are limited. Whereas complete responses (CRs) to B-cell depletion in ITP usually last for 1 year in adults, partial responses (PRs) are less durable. Comparable data do not exist for children and 5-year outcomes are unavailable. Patients with ITP treated with rituximab who achieved CRs and PRs (platelets > 150 × 10(9)/L or 50-150 × 10(9)/L, respectively) were selected to be assessed for duration of their response; 72 adults whose response lasted at least 1 year and 66 children with response of any duration were included. Patients had baseline platelet counts < 30 × 10(9)/L; 95% had ITP of > 6 months in duration. Adults and children each had initial overall response rates of 57% and similar 5-year estimates of persisting response (21% and 26%, respectively). Children did not relapse after 2 years from initial treatment whereas adults did. Initial CR and prolonged B-cell depletion predicted sustained responses whereas prior splenectomy, age, sex, and duration of ITP did not. No novel or substantial long-term clinical toxicity was observed. In summary, 21% to 26% of adults and children with chronic ITP treated with standard-dose rituximab maintained a treatment-free response for at least 5 years without major toxicity. These results can inform clinical decision-making.

Synergy of hybridization of bauhinia vahlii and kenaf fiber on mechanical and sliding wear properties of epoxy composites: A Grey Taguchi Optimization Study.

The present research work aims to develop Bauhinia vahlii fibre epoxy composites with incorporation of different weight percentage (wt%) of kenaf fiber as secondary reinforcement to elevate the mechanical and wear properties of prepared composites (through hand layup method). Higher value of mechanical properties like tensile strength-114.85 MPa, flexural strength- 64.64 MPa, and hardness- 57.2 Hv are achieved for bauhina vahlii-epoxy composites. In case of hybrid composites, tensile strength-161.92 MPa; flexural strength- 93.28 MPa; and hardness- 76.0Hv for bauhinia vahlii/kenaf-epoxy composites at 10 wt% of fiber reinforcement. The design of experiment is developed by Taguchi L9 orthogonal array to optimize the experimental run with three control factors; sliding velocity, fiber wt%, and normal load. In order to assess the multiple responses, the fabricated composite is analysed by Grey-Taguchi method with optimal factor setting to improve the output responses i.e. specific wear rate, tensile strength, flexural strength, and hardness. The optimal parameters which highly affect the properties of composites are sliding velocity (2.5 m/s), fiber wt% (10 wt %), and normal load (15 N). In wear mechanism analysis of composites by scanning electron microscopy (SEM), it is demonstrated that the synergy of hybridization of bauhinia vahlii and kenaf fiber improved the mechanical and wear properties of composites.

Theranostic applications of peptide-based nanoformulations for growth factor defective cancers.

Growth factors play a pivotal role in orchestrating cellular growth and division by binding to specific cell surface receptors. Dysregulation of growth factor production or activity can contribute to the uncontrolled cell proliferation observed in cancer. Peptide-based nanoformulations (PNFs) have emerged as promising therapeutic strategies for growth factor-deficient cancers. PNFs offer multifaceted capabilities including targeted delivery, imaging modalities, combination therapies, resistance modulation, and personalized medicine approaches. Nevertheless, several challenges remain, including limited specificity, stability, pharmacokinetics, tissue penetration, toxicity, and immunogenicity. To address these challenges and optimize PNFs for clinical translation, in-depth investigations are warranted. Future research should focus on elucidating the intricate interplay between peptides and nanoparticles, developing robust spectroscopic and computational methodologies, and establishing a comprehensive understanding of the structure-activity relationship governing peptide-nanoparticle interactions. Bridging these knowledge gaps will propel the translation of peptide-nanoparticle therapies from bench to bedside. While a few peptide-nanoparticle drugs have obtained FDA approval for cancer treatment, the integration of nanostructured platforms with peptide-based medications holds tremendous potential to expedite the implementation of innovative anticancer interventions. Therefore, growth factor-deficient cancers present both challenges and opportunities for targeted therapeutic interventions, with peptide-based nanoformulations positioned as a promising avenue. Nonetheless, concerted research and development endeavors are essential to optimize the specificity, stability, and safety profiles of PNFs, thereby advancing the field of peptide-based nanotherapeutics in the realm of oncology research.

Ionogels for flexible conductive substrates and their application in biosensing.

Ionogels are highly conductive gels made from ionic liquids dispersed in a matrix made of organic or inorganic materials. Ionogels are known for high ionic conductivity, flexibility, high thermal and electrochemical stability. These characteristics make them suitable for sensing and biosensing applications. This review discusses about the two main constituents, ionic liquids and matrix, used to make ionogels and effect of these materials on the characteristics of ionogels. Here, the material properties like mechanical, electrochemical and stability are discussed for both polymer matrix and ionic liquid. We have briefly described about the fabrication methods like 3D printing, sol-gel, blade coating, spin coating, aerosol jet printing etc., used to make films or coating of these ionogels. The advantages and disadvantages of each method are also briefly summarized. Finally, the last section provides a few examples of application of flexible ionogels in areas like wearables, human-machine interface, electronic skin and detection of biological molecules.

Wearable sweat chloride sensors: materials, fabrication and their applications.

Chloride is a crucial anion required for multiple functions in the human body including maintaining acid-base balance, fluid balance, electrical neutrality and supporting muscles and nerve cells. Low-chloride levels can cause nausea, diarrhoea, etc. Chloride levels are measured in different body fluids such as urine, serum, sweat and saliva. Sweat chloride measurements are used for multiple applications including disease diagnosis, sports monitoring, and geriatric care. For instance, a sweat chloride test is performed for cystic fibrosis screening. Further, sweat also offers continuous non-invasive access to body fluids for real-time monitoring of chloride that could be used for sports and geriatric care. This review focuses on wearable chloride sensors that are used for periodic and continuous chloride monitoring. The multiple sections in the paper discuss the clinical significance of chloride, detection methods, sensor fabrication methods and their application in cystic fibrosis screening, sports and geriatric care. Finally, the last section discusses the limitation of current sensors and future directions for wearable chloride sensors.

Solid-state, reagent-free and one-step laser-induced synthesis of graphene-supported metal nanocomposites from metal leaves and application to glucose sensing.

The laser-induced method to prepare three-dimensional (3D) porous graphene has been widely used in many fields owing to its low-cost, easy operation, maskless patterning and ease of mass production. Metal nanoparticles are further introduced on the surface of 3D graphene to enhance its property. The existing methods, however, such as laser irradiation and electrodeposition of metal precursor solution, suffer from many shortcomings, including complicated procedure of metal precursor solution preparation, strict experimental control, and poor adhesion of metal nanoparticles. Herein, a solid-state, reagent-free, and one-step laser-induced strategy has been developed for the fabrication of metal nanoparticle modified-3D porous graphene nanocomposites. Commercial transfer metal leaves were covered on a polyimide film followed by direct laser irradiation to produce 3D graphene nanocomposites modified with metal nanoparticles. The proposed method is versatile and applicable to incorporate various metal nanoparticles including gold silver, platinum, palladium, and copper. Furthermore, the 3D graphene nanocomposites modified with AuAg alloy nanoparticles were successfully synthesized in both 21 Karat (K) and 18K gold leaves. Its electrochemical characterization demonstrated that the synthesized 3D graphene-AuAg alloy nanocomposites exhibited excellent electrocatalytic properties. Finally, we fabricated LIG-AuAg alloy nanocomposites as enzyme-free flexible sensors for glucose detection. The LIG-18K electrodes exhibited the superior glucose sensitivity of 1194 µA mM-1 cm-2 and low detection limits of 0.21 µM. The LIG-21K nanocomposite sensors showed two linear ranges from 1 µM to 1 mM and 2 mM-20 mM with good sensitivity. Furthermore, the flexible glucose sensor showed good stability, sensitivity, and ability to sense in blood plasma samples. The proposed one-step fabrication of reagent-free and metal alloy nanoparticles on LIG with excellent electrochemical performance opens up possibilities for diversifying potential applications of sensing, water treatment and electrocatalysis.

Prospective Randomized Trial of Antibiotic Prophylaxis Duration for Percutaneous Nephrolithotomy in Low-Risk Patients.

Introduction and Objective: Postoperative infection and sepsis account for the most common complications following percutaneous nephrolithotomy (PCNL), as high as 14% in low-risk patients. Although the American Urological Association (AUA) recommends perioperative antibiotics for 24 hours or less for PCNL, practice patterns vary regarding duration of antibiotic therapy. We aimed to compare the efficacy of 24-hour antibiotic coverage vs short-course protocol of antibiotic prophylaxis for PCNL. Materials and Methods: Low-risk patients with a sterile preoperative urine culture undergoing PCNL were prospectively randomized to antibiotics for up to 24 hours after procedure (24Hr) or continued until external urinary catheters were removed (CR) study groups. Patients were given a first generation cephalosporin, or ciprofloxacin in patients with penicillin allergy. Exclusion criteria included age <18 years, receiving antibiotics immediately before the procedure, history of urosepsis, presence of indwelling catheter >1 week, multistage procedure, immunosuppression, pregnancy, multiple antibiotic allergies, and patients who are breastfeeding. Results: Ninety-eight patients were randomized to either 24Hr (n = 49) or CR (n = 49). Mean duration of antibiotic administration was 20.6 and 34.0 hours in the 24Hr and CR groups (p = 0.04), respectively. Age, comorbidities, stone size, operative time, number of punctures, dilations, and proportion of "tubeless" procedures were similar between groups. There were no differences in febrile episodes, rates of systemic inflammatory response syndrome, bacteremia, or culture-proven postoperative urinary tract infection between the 24Hr and CR groups. Overall complication rates were similar between groups. In a subgroup analysis which excluded "tubeless" patients (24 and 29 patients in 24Hr and CR groups, respectively), no differences were seen in postoperative outcomes. Conclusions: In a randomized, prospective study, we found that a 24-hour protocol for antibiotic prophylaxis is not associated with increased risk of infection-related events compared to giving antibiotics until external catheters are removed in patients with low infectious risk undergoing PCNL. Clinicaltrials.gov: NCT02579161.

Which clinical research questions are the most important? Development and preliminary validation of the Australia & New Zealand Musculoskeletal (ANZMUSC) Clinical Trials Network Research Question Importance Tool (ANZMUSC-RQIT).

BACKGROUND AND AIMS: High quality clinical research that addresses important questions requires significant resources. In resource-constrained environments, projects will therefore need to be prioritized. The Australia and New Zealand Musculoskeletal (ANZMUSC) Clinical Trials Network aimed to develop a stakeholder-based, transparent, easily implementable tool that provides a score for the 'importance' of a research question which could be used to rank research projects in order of importance. METHODS: Using a mixed-methods, multi-stage approach that included a Delphi survey, consensus workshop, inter-rater reliability testing, validity testing and calibration using a discrete-choice methodology, the Research Question Importance Tool (ANZMUSC-RQIT) was developed. The tool incorporated broad stakeholder opinion, including consumers, at each stage and is designed for scoring by committee consensus. RESULTS: The ANZMUSC-RQIT tool consists of 5 dimensions (compared to 6 dimensions for an earlier version of RQIT): (1) extent of stakeholder consensus, (2) social burden of health condition, (3) patient burden of health condition, (4) anticipated effectiveness of proposed intervention, and (5) extent to which health equity is addressed by the research. Each dimension is assessed by defining ordered levels of a relevant attribute and by assigning a score to each level. The scores for the dimensions are then summed to obtain an overall ANZMUSC-RQIT score, which represents the importance of the research question. The result is a score on an interval scale with an arbitrary unit, ranging from 0 (minimal importance) to 1000. The ANZMUSC-RQIT dimensions can be reliably ordered by committee consensus (ICC 0.73-0.93) and the overall score is positively associated with citation count (standardised regression coefficient 0.33, p<0.001) and journal impact factor group (OR 6.78, 95% CI 3.17 to 14.50 for 3rd tertile compared to 1st tertile of ANZMUSC-RQIT scores) for 200 published musculoskeletal clinical trials. CONCLUSION: We propose that the ANZMUSC-RQIT is a useful tool for prioritising the importance of a research question.

MyD88-dependent production of IL-17F is modulated by the anaphylatoxin C5a via the Akt signaling pathway.

The interleukin-17 (IL-17) family of cytokines plays important roles in innate immune defenses against bacterial and fungal pathogens. While much is known about IL-17A, much less information is available about the IL-17F isoform. Here, we investigated gene expression and release of IL-17F and its regulation by the complement system. IL-17F was produced in mouse peritoneal elicited macrophages after TLR4 activation by LPS, peaking after 12 h. This effect was completely dependent on the presence of the adaptor protein MyD88. The copresence of the complement activation product, C5a (EC(50)=10 nM), amplified IL-17F production via the receptor C5aR. In vitro signaling studies indicated that LPS or C5a, or the combination, caused phosphorylation of Akt occurring at threonine 308 but not at serine 473. Treatment of macrophages with pharmacologic inhibitors of PI3K-Akt greatly reduced production of IL-17F as well as mRNA for IL-17F. In endotoxemia, C5a levels peaked at 6 h, while IL-17F levels peaked between 6-12 h. Full in vivo production of IL-17F during endotoxemia required C5a. A similar result was found in the cecal ligation and puncture sepsis model. These data suggest that maximal production of IL-17F requires complement activation and presence of C5a.

Significance of Educational Literature and Diabetes Log Sheet on Hemoglobin A1c.

Diabetes mellitus (DM) is a major cause of morbidity worldwide. The prevalence of DM has doubled over the last 35 years and is escalating. Various complications and manifestations of diabetes have caused numerous deaths worldwide, with numbers increasing every year. There have been many advances and breakthroughs over the past decade in the management of DM. The major focus of many research studies has been to evaluate effective medication combinations, preventative measures, and the way to control such morbid conditions. Our focus in this review is to discuss specific secondary prevention techniques with the diabetes log sheet and educational literature on its effectiveness in controlling diabetes. Hemoglobin A1c (HbA1c) has been accepted as a diabetes control measure in many resources worldwide. Here, we have assessed articles on the effectiveness of the diabetes log sheet and educational literature on HbA1c levels. We will begin with a few key points to acknowledge diabetes initially, followed by discussing the effectiveness of the diabetes log sheet and literature on HbA1c.

Facile fabrication of conductive MoS2 thin films by sonication in hot water and evaluation of their electrocatalytic performance in the hydrogen evolution reaction.

Molybdenum disulfide (MoS2) has long been used in catalysis and is a promising material for energy conversion devices. In order to utilize MoS2 in electrocatalytic applications, it needs to be sufficiently conductive. Even though a metallic 1T phase of MoS2 exists, its exfoliation process is expensive and difficult to scale because it involves hazardous materials and procedures, limiting its practical applications. We have previously reported an efficient and environmentally friendly procedure to exfoliate conductive MoS2 via sonication in very dilute aqueous hydrogen peroxide. Here, we report a new way of exfoliating heavily doped conductive MoS2 by sonication in pure water at 60 °C without additives. Conductivity measurements, Raman spectroscopy and X-ray photoelectron spectroscopy demonstrate that controlling the sonication time and temperature lead to the generation of small quantities of hydrogen peroxide in the water that interact with MoS2 to form a small amount of sub-stoichiometric MoO3-y . This impurity acts as a dopant and is responsible for the increase in conductivity of the MoS2 films without compromising their structural integrity. We also evaluate the performance of the doped MoS2 films as electrocatalysts in the hydrogen evolution reaction. We elucidate the mechanistic origin of the catalytic properties of these materials which may be of future use to develop a family of electrocatalysts based on doped MoS2.

Physical and Mechanical Properties of Natural Leaf Fiber-Reinforced Epoxy Polyester Composites.

In recent times, demand for light weight and high strength materials fabricated from natural fibres has increased tremendously. The use of natural fibres has rapidly increased due to their high availability, low density, and renewable capability over synthetic fibre. Natural leaf fibres are easy to extract from the plant (retting process is easy), which offers high stiffness, less energy consumption, less health risk, environment friendly, and better insulation property than the synthetic fibre-based composite. Natural leaf fibre composites have low machining wear with low cost and excellent performance in engineering applications, and hence established as superior reinforcing materials compared to other plant fibres. In this review, the physical and mechanical properties of different natural leaf fibre-based composites are addressed. The influences of fibre loading and fibre length on mechanical properties are discussed for different matrices-based composite materials. The surface modifications of natural fibre also play a crucial role in improving physical and mechanical properties regarding composite materials due to improved fibre/matrix adhesion. Additionally, the present review also deals with the effect of silane-treated leaf fibre-reinforced thermoset composite, which play an important role in enhancing the mechanical and physical properties of the composites.

Molecular Combustion Properties of Nanoscale Aluminum and Its Energetic Composites: A Short Review.

Remarkable progress has been established in the field of nanoenergetic materials (mixture of nanoscale fuel and oxidizer) since the advent of nanotechnology. Combustion of nanoenergetic materials depends on many key factors like synthesis route, equivalence ratio, morphology of constituents, and arrangements and handling of materials. For tailoring and tuning of the combustion properties of nanoenergetics, sound knowledge of the reaction mechanism is needed; in this review article a schematic study on the reaction mechanism is presented. By employing various routes and strategies in synthesizing and nanoengineering of the fuel or/and oxidizer to realize a significant evolution from normal physical mixing of nanopowders to the formulation of core/shell nanostructures, the nanoenergetic materials achieved the best ever combustion properties in terms of combustion reactivity, ignition sensitivity, energy density, etc. Overall, in this article, a critical state-of-the-art review of the existing literatures has been conducted to feature the main developments in the molecular combustion modeling of melting, oxidation, and core-shell reaction/diffusion of nanoaluminum and the molecular modeling of combustion reactivity and ignition sensitivity of nanoenergetic materials.