Computational electrocatalysis beyond conventional hydrogen electrode model: CO2 reduction to C2 species on copper facilitated by dynamically formed solvent halide ions at the solid-liquid interface.

The reduction of CO2 into value-added chemicals and fuels has been actively studied as a promising strategy for mitigating carbon dioxide emissions. However, the dilemma for the experimentalist in choosing an appropriate reaction medium and neglecting the effect of solvent ions when using a simple thermochemical model, normally leads to the disagreement between experimental observations and theoretical calculations. In this work, by considering the effects of both the anion and cation, a more realistic CO2 reduction environment at the solid-liquid interface between copper and solvent ions has been systematically studied by using ab initio molecular dynamics and density functional theory. We revealed that the co-occurrence of alkali ions (K+) and halide ions (F-, Cl-, Br-, and I-) in the electric double layer (EDL) can enhance the adsorption of CO2 by more than 0.45 eV compared to that in pure water, and the calculated energy barrier for CO-CO coupling also decreases 0.32 eV in the presence of I ion on a negatively charged copper electrode. The hydrated ions can modulate the distribution of the charge near the solid-liquid interface, which significantly promotes CO2 reduction and meanwhile impedes the hydrogen evolution reaction. Therefore, our work unveils the significant role of halide ions at the electrode-electrolyte interface for promoting CO2 reduction on copper electrode.

Predicting opinion using deep learning: From burning to sustainable management of organic waste in Indian State of Punjab.

In winter season, the burning of crop residues for ease of sowing the next crop, along with industrial emissions and vehicular pollution leads to settling of a thick layer of smog in northern part of India. Therefore, to understand the opinion of farmers regarding sustainable management of organic waste, the present study was conducted in Ludhiana district of Indian state of Punjab. An ex post facto research design was used and a total of 800 dairy farmers having significant crop area were selected randomly for the study, grouped equally as small and large dairy farmers. Results revealed that majority of farmers had a highly favourable opinion regarding organic waste management due to the fact that they were aware of the ill-effects of undesirable practices like crop residue burning. Further, to predict the farmers' opinion and the effect of independent variables on farmers' opinion, a multi-layer perceptron feed-forward deep neural network was developed with mean squared error of 0.036 and 0.137 for validation and training data sets respectively, marking a novel approach of analysing farmers' behaviour. The neural network highlighted that with increase in the magnitude of input variables, namely, education, experience in dairying, information source utilisation, knowledge regarding organic waste management, etc., the farmers' opinion regarding sustainable waste management increases. The study concluded with the impression that cognitive processes like education, information and knowledge play a significant role in forming the opinion of the farmers. Therefore, efforts focusing on enhancing cognition should be made for sustainable management of organic waste.

Activating Hydrogen Evolution Reaction on Carbon Nanotube via Aryl Functionalisation: The Role of Hybrid sp2-sp3 Interface and Curvature.

The hydrogen evolution reaction (HER) is a remarkable mechanism which yields the production of hydrogen through a process of water electrolysis. However, the evolution of hydrogen requires highly conductive and stable catalysts, such as the noble metal platinum (Pt). However, the problem lies in the limitations that this catalyst and others of its kind present. Due to limited availability, as well as the costs involved in acquiring such catalysts, researchers are challenged to manufacture catalysts that do not present these limitations. Carbon nanotubes (CNTs), which are nanomaterials, are known to have a wide range of applications. However, specifically, the pristine carbon nanotube is not suitable for the HER due to the binding free energy of its positive H-atoms. Hence, for the first time, we demonstrated the use of the proposed aryl-functionalised catalysts, i.e., Aryl-L@SWCNT (L = Br, CCH, Cl, CO2CH3, F, I, NO2, or t-butyl), along with the effect of the sp2-sp3 hybridised interface through the density functional theory (DFT). We performed calculations of single-walled carbon nanotubes with multiple aryl functional groups. By employing the DFT calculations, we proved that the curvature of the nanotubes along with the proposed aryl-functionalised catalysts had a noteworthy effect on the performance of the HER. Our study opens the door to investigating a promising group of catalysts for sustainable hydrogen production.

Applicability of moyer's probability tables in north indian population of 16-18 years old.

AIMS: To determine the applicability of Moyer's probability tables in North Indian population of 16-18 year olds and to formulate a new regression equation for the same group of population. SETTING AND DESIGN: Evaluative Study. METHODS AND MATERIAL: 1000 children aged 16-18 years were selected as sample for the measurement of mesiodistal widths of permanent mandibular incisors, maxillary and mandibular canines and premolars using study models. The recorded values were then subjected to statistical analysis. STATISTICAL ANALYSIS USED: Software Package for Social Sciences (SPSS) software version 22.0. RESULTS: The actual widths of the canine and premolars showed highly significant differences in maxilla and in mandible (P < 0.001), compared to widths predicted by Moyer's probability table at 75th percentile. CONCLUSION: Moyer's mixed dentition analysis was not an accurate method for prediction in North Indian population as it showed overestimation of tooth sizes. Hence, new regression equation has been formulated for the same.

Biosynthesis of Metal Nanoparticles from Leaves of Ficus palmata and Evaluation of Their Anti-inflammatory and Anti-diabetic Activities.

Metal nanoparticles (AgNPs and ZnONPs) were synthesized using a green methodology with the green leaves extract of the Bedu (Ficus palmata) tree as a reducing agent and the support of natural fibers. The synthesized AgNPs and ZnONPs were characterized by several techniques, including ultraviolet-visible spectral analysis, powder X-ray diffraction crystal analysis, scanning electron microscopy, EDAX, transmission electron microscopy, and Fourier transform infrared spectroscopy, which confirmed that the synthesized particles are in the nano range (1-100 nm), i.e., 30 nm for AgNPs with polydispersity and a spherical shape, whereas the average size of synthesized ZnONPs is 34 nm and they seem to exhibit a distorted spherical shape. The results of thermogravimetric analysis confirmed a weight loss of 18.02% for AgNPs under exothermic conditions due to the desorption of water, and ZnONPs show weight loss between 265 and 500 °C. Both synthesized MNPs are highly thermally stable. Anti-inflammatory and anti-diabetic studies of metal NPs have been evaluated. The AgNPs and ZnONPs of F. palmata leaves showed remarkably highly potent activity for respective strains. In vitro anti-diabetic activity was found for inhibition of α-amylases and α-glucosidases by synthesized silver nanoparticles.

Knowledge regarding avulsion, reimplantation and mouthguards in high school children: Organised sports-related orodental injuries.

PURPOSE: To assess knowledge, awareness and attitude of high school children involved in various sports activities regarding avulsion, reimplantation and mouthguard use. MATERIALS AND METHODS: An interview-based study was conducted among high school children in the age group of 8-16 years (n = 1105). A questionnaire was given to children and parents which included questions based on knowledge of children regarding avulsion, reimplantation, consequences of losing teeth, mouthgards and their usage and preferred media for tooth transportation. The research proposal was submitted to the ethics committee and the study design was approved. Data analysis included descriptive statistics and Statistical Package for the Social Sciences (SPSS) software. RESULTS: Only 37.6% of the children knew that their teeth can be completely knocked out with injury and 20.1% knew that a knocked-out tooth can be replanted. The preferred media for tooth transportation were gauze/cotton (27.2%), handkerchief (17.5%), paper (14%), water (13.8%) and cellophane (1.3%), i.e. 81.3% of the children preferred dry transport media. Among the children playing contact sport, 53.8% did not know about mouthguards and the rest 46.2% knew about it, but most of them never used it. CONCLUSION: Considering the lack of awareness among children, as well as the people around them, there appears to be a crucial need for education of public and to determine dental manpower and dentists to increase awareness.

Defective Graphene on the Transition-Metal Surface: Formation of Efficient Bifunctional Catalysts for Oxygen Evolution/Reduction Reactions in Alkaline Media.

Supported single-atom catalysts (SACs) have attracted enormous attention because of their high selectivity, activity, and efficiency, compared to conventional nanoparticles and metal bulk catalysts. However, all of these unique merits rely on the stability of the SAC, as reported by many investigators. To avoid aggregation of single-metal atoms and maintain the high performance of the SAC, various substrates have been tried to support them, particularly on graphene nanosheets. A spontaneous interface phenomenon between graphene and the Co (and Ni) substrate discovered in this work is that the holes in the graphene layer can stimulate metal atoms to pop up from a metal substrate and fill the double vacancy in graphene (DV-G) and stabilize on the graphene surface. The unique structure of the lifted metal atom is expected to be useful for the bifunctional SAC for electrocatalytic oxygen evolution reactions (OERs) and oxygen reduction reactions (ORRs). Our first-principles calculations indicate that the DV-G on the Co(0001) surface can serve as an excellent bifunctional OER/ORR catalyst in alkaline media with extremely low overpotentials of 0.39 V for OER and only 0.36 V for ORR processes, which are even lower than those for previously reported bifunctional catalysts. We believe that the catalytic activity stems from the interface coupling effect between the DV-G and metal substrate, as well as the charge redistribution in the graphitic sheet.

Pediatricians' view on early childhood caries and oral health in a north region of India: A cross-sectional study.

BACKGROUND: The majority of oral diseases in children are preventable. The pediatricians owing to the unique position they occupy in child care are invaluable in achieving standard oral and dental healthcare in children. This study was aimed to assess pediatrician's knowledge, attitude, and awareness toward early childhood caries (ECC), oral health, and treatment needs of their patients. METHODS: A total of 65 pediatricians were randomly selected for the study and were requested to fill out an objective questionnaire pertaining to individual details, approach toward pediatric dentistry, and knowledge level of oral health, without providing any oral health information. RESULTS: About 58.5% of pediatricians acknowledged the importance of pediatric dentistry. About 72.7% of pediatricians perform oral examination regularly. Around 17% of pediatricians have knowledge of the ECC. Only 32.3% of pediatricians acknowledged the cariogenicity of medicated syrups. CONCLUSION: This study shows those pediatricians who were surveyed had poor knowledge regarding ECC, oral health, and dental treatment need in children. Pediatricians need to update themselves on recent recommendations.

Comparative Clinical and Microbial Evaluation of Two Endodontic File Systems and Irrigating Solutions in Pediatric Patients.

AIMS: The purpose of the study was to determine the best combination for chemomechanical preparation in primary teeth using two endo file systems (hand and rotary) along with two different irrigants. MATERIALS AND METHODS: Sixty primary molars indicated for pulpectomy, underwent chemomechanical preparation using endo files (H hand files and rotary Protaper files) and root canal irrigating solutions (Smearclear and QMiX). Samples from root canals were collected before and after the chemomechanical preparation of the canal and were cultured for microbial analysis of Enterococcus faecalis. RESULTS: Endodontic irrigating solutions showed significant differences of effectiveness on the growth inhibition of bacterial strain. The present study confirmed that the in vivo antimicrobial efficacy of QMiX solution was statistically significant when compared to the Smearclear solution. CONCLUSION: Based on the antimicrobial efficacy observed in the present study, it may be concluded that QMiX has a great potential than Smearclear as an intracanal irrigation solution in primary teeth and rotary preparation may be considered as more efficient and time-saving mechanical preparatory technique in primary molars.

A nano silver-xerogel (Ag nps@modified TEOS) as a newly developed nanocatalyst in the synthesis of benzopyranopyrimidines (with secondary and primary amines) and gem-bisamides.

Silver nanoparticles have been prepared from a chemical reduction approach and supported on modified TEOS (tetraethylorthosilicate) xerogels to be studied as a nanocatalyst in the conversions of benzopyranopyrimidines (with primary as well as secondary amines along with the mechanism by trapping the imine intermediate) and also in the synthesis of gem-bisamides. Different conditions for the performance of the nanocatalyst have been screened and tolerance with respect to variable functionalities has been observed, resulting in excellent yields; and confirmation of products synthesized has been done using studies like 1H NMR, 13C NMR and mass analysis. Also, SEM-EDX and TEM of the nanocatalyst have been performed to know the internal and external morphology, size and elemental composition. UV and XRD analysis to confirm the silver nanoparticles' and xerogel's presence, TGA to study the thermal stability and FTIR to study the modification pattern of the nanocatalyst have been undertaken and presented in this work.

Insulin Syringe: A Gimmick in Pediatric Dentistry.

AIM: The management of pain and anxiety in dentistry encompasses a number of procedural issues, including the delivery of anesthetic solution. One of the most important ways to manage the behavior of children is pain control. Trypanophobia is very common among dental patients and the most important goal of guidelines on behavior guidance for pediatric dental patient is to ease fear and anxiety in dental procedures in children. For the stated reasons, the purpose of the present study was to record child's pain sensation both objectively and subjectively while receiving dental local anesthesia using conventional syringes and diabetic needles. MATERIALS AND METHODS: Twenty children of age group 6 to 12 years undergoing routine dental procedures participated in the study. Every child acted as one's own control, while receiving treatment on the opposite side of the same arch. Each patient was randomly assigned to receive the injection either with conventional syringe or diabetic needle for the first visit, while the injection with the other needle was administered during the second visit. Rating scales were used for objective and subjective evaluations. RESULTS: Statistical analysis of the measurements were made using Wilcoxon signed U test and Mann-Whitney U test which showed the mean sound, eye, motor (SEM) score difference using insulin syringe. The outcome was statistically significant when compared using the mean ranks between male and female patients with that of control group. CONCLUSION: It can be concluded that diabetic syringes exhibit clinical advantage and its use in pediatric dentistry for local anesthetics (LA) infiltration can prove beneficial.How to cite this article: Kour G, Masih U, Singh C, Srivastava M, Yadav P, Kushwah J. Insulin Syringe: A Gimmick in Pediatric Dentistry. Int J Clin Pediatr Dent 2017;10(4):319-323.

Iron nanotube-silica composite (ZVI-S-PCAT modified silica composite) preparation, characterization and application as a recyclable catalytic system for 5-membered ring organic transformations.

Iron nanotube silica composite have been synthesized and studied through particle-size analysis, FTIR, SEM-EDX, TEM, XRD, UV, VSM, TGA-DTA and XPS techniques. The application of nanoframeworks as sustainable recyclable catalytic systems has been observed for azole cyclic ring organic transformations. The good reaction yields and characterization through (1)H NMR, (13)C NMR and mass analysis support the performance of the nanoframeworks. We also present here the synthesis of two novel compounds. Also the prepared nanoframework has been observed to show soft magnetism which provides a scope to be used in sensing devices.