Search

Present work reports preparation of colloidal single/few layer Ti3C2Tx MXene flakes using minimally intensive layer delamination (MILD) method for rapid electroanalytical screening of carbamate pesticides. Lithium fluoride salt and hydrochloric acid (7.5 M LiF/9M HCl) was used to produce in-situ generated HF as etchant to remove Al successfully from Ti3AlC2 MAX phase. Unlike the clay method (5 M LiF/6M HCl), this methodology simplified Ti3C2Tx synthesis protocol resulting in Li+ ions intercalated Ti3C2Tx which was delaminated without further sonication. The delaminated Ti3C2Tx flakes were found to be single/few layered sheets with mostly –OH and –O terminated surface groups. The characteristic 002 peak observed in X-ray diffraction (XRD) at 2θ = 6.4° with interplaner distance of 1.1137 nm suggested broadening of the peak attributed to the presence of Li+ ions between Ti3C2Tx flakes. Delaminated Ti3C2Tx flakes were utilized as working electrode which demonstrated simultaneous and selective detection of carbamate pesticides methiocarb and diethofencarb by voltammetry. The oxidation peaks of the two pesticides were well separated by a potential difference of 0.35 V in 0.5 M H2SO4 and DPV detection limits were calculated as 0.19 μg mL−1 and 0.46 μg mL−1 for methiocarb and diethofencarb respectively. Ti3C2Tx flakes as electrochemical sensor exhibited long term stability and acceptable recoveries in real sample for environmental applications.

The COVID-19 pandemic has created a situation where wearing personal protective masks is a must for every human being and introduced them as a part of everyday life. This work demonstrates a new functionality embedded in single-use face masks through an embroidered humidity sensor. The design of the face mask humidity sensor is comprised of interdigitated electrodes made of polyamide-based conductive threads and common polyester threads which act as a dielectric sensing layer embroidered between them. Therefore, the embroidered sensor acts as a capacitor, the performance of which was studied in increasing humidity conditions in the frequency range from 1 Hz to 100 kHz. The moisture adsorbed by sensitive hygroscopic polyester threads altered their dielectric and permittivity properties which were detected by the change in capacitance values of the face mask sensors at different relative humidity (RH) levels. The calculated limit of detection (LOD) values for the two proposed sensors at different frequencies (1, 10, and 100 kHz) were found in the range from 11.46% RH-27.41% RH and 29.79% RH-38.65% RH. The tested sensors showed good repeatability and stability under different humidity conditions over a period of 80 min. By employing direct embroidery of silver-coated polyamide conductive threads and moisture-sensitive polyester threads onto the face mask, the present work exploits the application of polymer-based textile materials in developing novel stretchable sensing devices toward e-textile applications.

Reverse breeding is a modern plant breeding method for producing complementing parental lines for any heterozygous plant through achaismatic meiosis (meiosis without crossovers). The achiasmatic meiosis leads to univalent segregation at meiotic metaphase-I and the generation of aneuploid gametes. These gametes are then regenerated as doubled-haploid (DH) plants. Each DH carries combinations of its parental chromosomes, and complementing DH pairs can be crossed to reconstitute the initial hybrid. In reverse breeding, the suppression of meiotic crossovers in a hybrid ensures the transmission of non-recombinant chromosomes to haploid gametes. The PAIR2 gene is required for homologous chromosome synapsis at meiosis-I in plants. An insertional mutation in the rice PAIR2 gene, the ortholog of Arabidopsis thaliana ASY1, results in a defect in homologous chromosome pairing during meiosis, display univalents at metaphase-I. Essentially, reverse breeding follows an approach akin to the generation of a DH population from an F1 hybrid, carrying a dominant-acting transgene that down-regulates the expression of Disrupted Meiotic cDNA1 (DMC1), resulting in inhibition of crossover recombination and thereby enabling intact-chromosome inheritance. In earlier reports on reverse breeding in A. thaliana, a hybrid was constructed of using two of its natural ecotypes (Col-0 and Laer-0), carrying an RNAi transgene targeting the meiotic recombinase (RecA homolog) DMC1 that prevented the formation of meiotic crossover recombination. This method mainly included steps: (i) the generation and selection of RNAi: DMC1 transformed lines; (ii) the generation of achiasmatic hybrids; (iii) the crossing of achiasmatic hybrids to GFP-tailswap to generate haploid chromosome substitution lines (CSLs); (iv) the generation of DHs by spontaneous doubling of haploid CSLs; and (v) the crossing of complementing CSLs to recreate the initial hybrid. The scope of reverse breeding could be envisioned for the improvement of agricultural crops, as it may enable the generation of parental breeding lines for the recreation of hybrid.

In the present study, the experimental validation of Genic-SSR markers developed from transcriptome data of Selaginella bryopteris was done, and their cross-species transferability was examined across genus and species of pteridophytes. Twenty primer pairs were designed to amplify the various repeats of SSR markers, and first validated with complementary DNA (cDNA) of S. bryopteris. Out of twenty primer pair, fourteen primer pairs (70%) could amplify the DNA of S. bryopteris. Among Azolla spp., four SSR markers (SbSSR4, SbSSR12, SbSSR14 and SbSSR18) were found to be 100% transferable, while others SbSSR13 (80%), SbSSR3 and SbSSR20 (50%) and four markers SbSSR6, SbSSR10, SbSSR15 and SbSSR19 (10%). Out of twenty validated primers, 11 primers were found to be polymorphic. The value of polymorphism information content (PIC) ranged from 0.47 to 0.86 with an average of 0.49. The Jaccard’s similarity coefficient ranged from 0.10 to 0.93 which revealed a wide range of genetic identity. The similarity between A. fuliculoids and A. maxicana (0.93), and A. pinnata and A. rubra (0.93) was high and while low similarity coefficient of S. bryopteris with P. vittata (0.18), local fern (0.20) and with Azolla spp. (0.10- 0.25). Two major Clusters formed based on UPGMA i.e. S. bryopteris, P. vittata, local fern in Cluster I and Azolla spp. in Cluster II, a clear divergence between S. bryopteris and other pteridophytes. BAUS1 was found to be more genetically divergent followed by BAUS2, BAUS1 and BAUS3 in comparison to known species of Azolla. The transferability of Genic- SSR markers of S. bryopteris demonstrated the utility for elucidating genetic relationship among selected pteridophytes.

In this present study, eight genotypes of Brassica juncea comprising four tolerant (IC-399802, IC-491089, IC-312545, IC-312553) and four susceptible (IC-385686, IC-264131, IC-426392, Laxmi) genotypes for aphid tolerance were used to generate Sequence Characterized Amplified Region (SCAR) markers through dominant PCR based markers (51 RAPD and 12 ISSR markers). 13 RAPD (Random Amplified Polymorphic DNA) and 8 ISSR (Inter Simple Sequence Repeat) markers were found to be polymorphic but only 3 primers OPE16 (RAPD), UBC 839 (ISSR) and UBC 864 (ISSR) were obtained which could distinguish tolerant genotypes from susceptible ones. OPE16 (RAPD) obtained unique band of size approx. 600 bp in susceptible genotypes while it was absent in the tolerant genotypes. Similarly, UBC 839 (ISSR) yielded ~800 bp unique band in bulk tolerant while UBC 864 (ISSR) yielded three bands of ~1200 bp, ~1000 bp, and ~500 bp in tolerant genotypes which was absent in the susceptible genotypes. These unique bands were excised to generate five sets of SCAR markers. Among the five sets of SCAR marker, only BJSCAR F1 and BJSCAR R1 set yielded the promising result in all for 4 susceptible genotypes as well as bulk susceptible and was absent in all the tolerant genotypes and Brassica fruticulosa (highly tolerant to aphid, used as a control). So, this SCAR marker developed could be successfully used in screening of B.juncea genotypes in future breeding programs.

The present work reports development of advanced nanosensor platform based on hierarchical 3D nanotubes assembled from MoS2 mono layers (3D MoS2NTs) for rapid and selective screening of well known carbamate fungicide, diethofencarb. The assembly of ultrathin MoS2 layers possessed mesopores and large specific surface area which enabled its potential implementation in electrode fabrication. Preparation of 3D MoS2NTs helped to avoid restacking and aggregation during its utilization as sensor material and manifested great sensing abilities towards electro-oxidation of diethofencarb. The LOD and LOQ for diethofencarb at 3D MoS2NTs/GCE were calculated as 0.32 ng μL−1 and 1.09 ng μL−1 in the concentration range of 1–55 ng μL−1 by square wave voltammetry (SWV) and further 0.63 ng μL−1 and 2.11 ng μL−1 in the concentration range of 1–35 ng μL−1 by differential pulse voltammetry (DPV). The developed 3D MoS2NTs nanosensor was successfully used to quantify diethofencarb in river water sample with satisfied recovery of 94.23%–105.46% justifying its analytical utility in pesticide screening. The study drives immense motivation towards sensing of hazardous pesticides using nanomaterials based advanced sensing devices for environmental monitoring.

The present work embodies outward oxygen atom transfer (OAT) reaction from pyridylbenzoxazole (L1) chelated oxorhenium(V) complex of type [ReOCl3(L1)], 1 towards oxophilic PMe2Ph resulting in the formation of reduced Re(III) derivative [Re(OPMe2Ph)Cl3(L1)], 4 containing oxidised phosphine trans to azole nitrogen. Another possible isomer (4a) having oxidised phosphine trans to pyridyl nitrogen has not been isolated. Structural elucidation of 4 reveals meridional disposition of three Cl atoms around the metal featuring distorted octahedral geometry. DFT analysis of isomers of type [Re(OPMe2Ph)Cl3(L1)] (4 and 4a) confirms isoenergetic nature in gas phase, however, stereospecific binding of L1 to Re(III) centre affording 4 as exclusive product is attributed to crystal packing force. 1 → 4 redox transformation has also been attended with the change in singlet → triplet spin state of the metal. Triplet state of 4 is more stable by ca. 15 kcal mol−1 compared to the singlet state in gas phase. Two electron paramagnetic nature (2.13 μB) in solid state affirms triplet ground state characterised with strong orbital coupling. Kinetic data for 1 → 4 transformation suggests associative pathway (ΔS≠ = ∼−36 J/K/mol) with no major structural reorganisation in the primary coordination sphere of the substrate and the reagent (ΔH≠ = ∼+10 kcal mol−1) to reach the transition state. Pyridylbenzthiazole (L2) chelated oxorhenium(V) complex of type [ReOCl3(L2)], 1b also reacts with PMe2Ph in a same manner to from [Re(OPMe2Ph)Cl3(L2)], 4b where the pyridyl nitrogen lies trans to phosphineoxide moiety unlike 4. The second order rate constants of OAT to PMe2Ph for [ReOCl3(L1)] are nearly two times higher than that of [ReOCl3(L2)] at all recorded temperatures due to difference in azole heteroatom electronegativity, ReV O bond length and ReVI/ReV reduction potential.

The present work reports the preparation of advanced functional nanostructures based on cobalt oxide supported mesoporous carbon framework (Co3O4@MCF) for electrochemical biosensing. Co3O4@MCF was synthesized by simple hythrothermal & pyrolysis method and further characterized by various microscopic and spectroscopic techniques. The transmission electron microscopic (TEM) images show the lattice fringes of crystalline Co3O4 with interlayer spacing of 0.24 nm. The characteristic 311 plane in X-ray diffraction (XRD) studies further confirmed the presence of crystalline Co3O4 on carbon frameworks. Reflection of prominent A1g peak along with D and G band in raman spectra confirmed the successful fabrication of Co3O4@MCF nanocomposite. Prepared Co3O4@MCF manifested great porosity, good biocompatibility and large surface area which allowed effective immobilization of glucose oxidase (GOx) onto its surface using chitosan (Chi) as a binder. Thus, a nanocomposite (Co3O4@MCF-Chi-GOx) modified glassy carbon electrode (GCE) was fabricated for highly selective detection of glucose using amperometry and cyclic voltammetry. The Co3O4@MCF-Chi-GOx/GCE electrode exhibited excellent biosensing performance for glucose monitoring with detection limit of (LOD) of 107.70 μM and reproducibility of 4.7% RSD. Moreover, the biosensor holds great promise for its effective implications in point-of-care diagnostics of small biomolecules.

Hydrogels are hydrophilic polymeric networks prepared by physical or chemical cross-linking of gelator molecules under optimum conditions. Being sensitive to external stimuli, hydrogels are integrated into signal transduction systems for generating possible responses upon interaction with target analytes to study various physiochemical/biochemical molecular recognition processes. In recent times, polymer based hydrogel materials have emerged as unique electrode modifying materials providing highly permeable matrix for easy diffusion of analytes and rapid electron transport. Polymeric architectures of hydrogels can accommodate different nanomaterials within its matrix through suitable interactions to form hydrogel nanocomposites. Further, high biocompatibility of hydrogels facilitates facile encapsulation and cross-linking of bioreceptors (eg. nucleic acid, protein) into polymer matrix and helps to retain their bioactivity during practical applications. Polymer hydrogel materials enable easy prototyping of electrodes using novel printing technologies for designing next generation advanced, flexible and portable bioelectronics with excellent sensing performances. The present article focuses on the implication of polymer hydrogels as high performance electrode materials. Taking relevant examples, nanomaterials incorporated polymer hydrogel based chemical sensors and bioreceptors embedded biosensors have been discussed for electrochemical detection of different analytes. Preparation of hydrogel modified electrodes and state-of-the-art sensing mechanisms have been briefly emphasized. Concluding remarks and future prospects regarding fabrication of hydrogel based smart electronics have been provided at the end.

Natural riverine areas mark ecotonal habitats harbouring a characteristically diverse faunal assemblage, especially birds that also use these habitats as pathways crucial for their movement. Increasingly, riverine systems are subjected to large-scale habitat alterations due to climatic fluctuations and anthropogenic changes. Therefore, it is important to understand broad-scale community patterns for conservation planning and prioritisation for these ecotone habitats. The Bhagirathi river is one of the major headwaters of the river Ganges; despite its rich and diverse fauna, little is known about the bird species that inhabit this montane region. This study presents an extensive list of 281 bird species from 59 families, their seasonal distribution and habitat associations as recorded from field surveys along the riverine areas between April 2013 and May 2018. The present communication simultaneously discusses a few noteworthy sightings for the region and provides a baseline for future research on the distribution of birds in the Western Himalaya.

Entropy based k-Nearest Neighbor pattern classification (EbkNN) is a variation of the conventional k-Nearest Neighbor rule of pattern classification, which exclusively optimizes the value of k-neighbors for each test data based on the calculations of entropy. The formula for entropy used in EbkNN is the one that has been defined popularly in information theory for a set of n different types of information (class) attached to a total of m objects (data points) with each object defined by f features. In EbkNN that value of k is chosen for discrimination of given test data for which the entropy is the least non-zero value. Other rules of conventional kNN are retained in EbkNN. It is concluded that EbkNN works best for binary classification. It is computationally prohibitive to use EbkNN for discriminating the data points of the test dataset into number of classes greater than two. The biggest advantage of EbkNN vis-à-vis the conventional kNN is that in one single run of EbkNN algorithm we get optimum classification of test data. But conventional kNN algorithm has to be run separately for each of the selected range of values of k, and then the optimum k to be chosen from amongst them. We also tested our EbkNN method on WDBC (Wisconsin Diagnostic Breast Cancer) dataset. There are 569 instances in this dataset and we made a random choice of first 290 instances as training dataset and the rest 279 instances as test dataset. We got an exceptionally remarkable result with EbkNN method- accuracy close to 100% and better than the ones got by most of the other researchers who worked on WDBC dataset.

Present work reports preparation of colloidal single/few layer Ti

Anterior cross bite is defined as “palatal positioning of the maxillary anterior teeth relative to the mandibularanterior teeth”.Various treatment options available are removable & fixed appliances. This is a case report ontreating a case of single anterior tooth crossbite during the mixed dentition using the “Hawley’s appliancewith posterior bite plane & Z’spring”. The active treatment time was 3 months in total & the treatmentoutcomes were followed up consequently for the next 4 months successfully

BACKGROUND: Community health officers (CHOs) are a newly introduced cadre of mid-level health-care providers who will man the health and wellness centers under Ayushman Bharat Mission in India. Need-based training will help them fulfil their role in early diagnosis, treatment, and referral of tuberculosis (TB) patients. The present study identified the gaps in the awareness about TB in a heterogeneous group of trainees and addressed them through need-based training. MATERIALS AND METHODS: A before and after the study was carried out in 110 trainee CHOs at Rural Medical College, Loni. In-depth interviews were conducted with public health experts and focus group discussion was conducted with trainees to gain the quality inputs. Structured questionnaires based on training objectives specifically pertaining to TB were designed. Training was provided with an emphasis on addressing the gaps identified in the pretest. Posttest evaluation was done at the end of the training to assess its effectiveness. Data were analyzed using the SPSS software version. 17.0 (Inc., Chicago, IL, USA). RESULTS: The mean pretest score was 15.15 (standard deviation [SD] = 3.55) which improved after 6 months training to 24.01 (SD = 1.223), i.e., from 60% to 96%. There was highly significant improvement in overall knowledge score of trainees (t = 28.124, df = 109, P < 0.001). There was a statistically significant improvement in scores of all topics at the end of 6 months training in both Nursing and Ayurved graduates. Except for knowledge regarding the treatment of multidrug-resistant TB (P = 0.004), knowledge about all other topics was comparable in nursing and Ayurved graduates at the end. CONCLUSIONS: Needs assessment proved effective in identifying the gaps in knowledge and skills of interdisciplinary trainee CHOs. Medical colleges with expertise in teaching, training, and health service provision can work with the public health system to provide a model for rapid upgrading and capacity building to meet health-care challenges such as TB.