This work delves into a methodology of modeling 2D materials and their structural engineering, considering an example of a recently synthesized 2D polyaramid (2DPA-1). A bottom-up approach similar to ...experimental techniques is implemented for modeling, and then its electronic structures and phonon spectrum and the quadratic nature of flexural phonons are analyzed. Furthermore, boron and nitrogen atoms are substituted for the carbon atom of the amide group of 2DPA-1, and their effects on its electronic properties, phonon spectrum, and mechanical properties are compared with those of pristine 2DPA-1 using density functional theory calculations. The ab initio molecular dynamics (AIMD) simulations validate the thermal stability of our system at high temperatures. The spin-polarized electronic structures reveal the transformation of pristine 2DPA-1 from a semiconductor to a half-metal and its magnetic behaviour upon nitrogen substitution. Constraining the quadratic nature of flexural phonons using the Born–Huang criteria significantly enhances the phonon spectra, leading to more accurate and reliable simulations. For modulated 2DPA-1, the elastic modulus varies between 17 and 27 N m −1 , and the absorption peaks shift from ∼5.15 eV to 2.42 eV, enabling the application of polymeric 2D nanomaterials in photocatalysis and sensing, where light absorption in the near-infrared region is important. Finally, validation of our methodology is confirmed, as computed Young's modulus (11.26–11.76 GPa) of 2DPA-1 matches excellently with the experimental value (12.7 ± 3.8 GPa). Overall, this study reveals the modeling of a newly synthesized polymeric 2D material, and tuning its properties results in smaller bandgaps and half-metallic and magnetic behaviours.
A significant increase in the incidence of fungal infections and drug resistance has been observed in the past decades due to limited availability of broad-spectrum antifungal drugs. Nanomedicines ...have shown significant antimicrobial potential against various drug-resistant microbes. Silver nanoparticles (AgNps) are known for their antimicrobial properties and lower host toxicity; however, for clinical applications, evaluation of their impact at cellular and molecular levels is essential. The present study aims to understand the cellular and molecular mechanisms of AgNp-induced toxicity in a common fungal pathogen,
.
AgNps were synthesized by chemical reduction method and characterized using UV-visible spectroscopy, X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy-energy dispersive X-ray spectroscopy, energy dispersive X-ray fluorescence, and zeta potential. The anti-
activity of AgNps was assessed by broth microdilution and spot assays. Effects of AgNps on cellular and molecular targets were assessed by monitoring the intracellular reactive oxygen species (ROS) production in the absence and presence of natural antioxidant, changes in surface morphology, cellular ultrastructure, membrane microenvironment, membrane fluidity, membrane ergosterol, and fatty acids.
Spherical AgNps (10-30 nm) showed minimum inhibitory concentration (minimum concentration required to inhibit the growth of 90% of organisms) at 40 μg/mL. Our results demonstrated that AgNps induced dose-dependent intracellular ROS which exerted antifungal effects; however, even scavenging ROS by antioxidant could not offer protection from AgNp mediated killing. Treatment with AgNps altered surface morphology, cellular ultrastructure, membrane microenvironment, membrane fluidity, ergosterol content, and fatty acid composition, especially oleic acid.
To summarize, AgNps affected multiple cellular targets crucial for drug resistance and pathogenicity in the fungal cells. The study revealed new cellular targets of AgNps which include fatty acids like oleic acid, vital for hyphal morphogenesis (a pathogenic trait of
). Yeast to hypha transition being pivotal for virulence and biofilm formation, targeting virulence might emerge as a new paradigm for developing nano silver-based therapy for clinical applications in fungal therapeutics.
An effort has been made to enhance the flexural fatigue lives of self compacting concrete (SCC) in which half of the natural aggregates (NA) were substituted with recycled concrete aggregates (RCA) ...by means of blended cements. Blended SCC mixes containing either silica fume (SF) or metakaolin (MK) along with cement, and fly ash (FA) was also adopted. Fatigue lives have been evaluated as mean value, design value life and theoretical value. The Weibull distribution parameters were utilized for the valuation of mean and design values of fatigue lives for different considered mixes. It has been observed that adding RCA in SCC causes degradation in the fatigue lives, which can be enhanced by adopting the blended mixture comprising of SF or MK, cement and FA. Both SF and MK established a promising result in improving fatigue lives. Still, the blend of MK in SCC contributed most effectively in enhancing the fatigue life of SCC comprising RCA.
The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2023 recommends a comprehensive multidimensional assessment for patients with chronic obstructive pulmonary disease (COPD) and ...stresses the need for evaluation of their health status and quality of life (QOL). COPD assessment test (CAT), clinical COPD questionnaire (CCQ) and St. George Respiratory questionnaire (SGRQ) are recommended by GOLD for such assessments. However, their correlation with spirometry in the Indian population is not known. Other similar questionnaires like COPD and sleep impact scale (CASIS), functional performance inventory-short form (FPI-SF) and COPD and asthma fatigue scale (CAFS) though used internationally as a research tool, are still in the offspring stage and have never been used in India. A cross-sectional study was hence conducted in the Department of Pulmonary Medicine, Government Medical College, Patiala, Punjab, India on 100 COPD patients. Patients were assessed for health status and QOL by CAT, CCQ, SGRQ, CASIS, FPI-SF and CAFS. The relationship between these questionnaires and airflow limitation was investigated. The majority of the patients were males (n=97) and >50 years of age (n=83), illiterate (n=72), had moderate/severe COPD and belonged to group B (n=66). The mean value of forced expiratory volume in one second (%FeV1) decreased with a deterioration in CAT and CCQ score grouping (p<0.001). Patients with poorer CAT and CCQ scores belonged to higher GOLD grades (kappa=0.33, p<0.001). The correlation of health-related quality of life (HRQL) questionnaires amongst each other, with FEV1 predicted and with GOLD grade was strong to very strong in most of the comparisons (p<0.01 in the majority). On comparison of GOLD grade with mean scores of HRQL questionnaires, it was seen that with the increase in GOLD grading from 1 to 4, the mean value of CAT, CCQ, SGRQ, CASIS, FPI SF and CAFS also deteriorated (p<0.001, p<0.001, p<0.001, p<0.005, p<0.001 and p<0.001, respectively). Various easy-to-use HRQL scores should be routinely used in outpatient departments for a comprehensive assessment of COPD patients. These questionnaires, in combination with clinical features, can help in providing a rough estimate of the severity of the disease at places where lung function assessments are not readily available.
Microbes can serve as mediators for the fabrication of complicated nano-structures, obviating the tedious and time-consuming methods of synthesis. The shape of a nanoparticle has a very prominent ...role in defining the functionality in prospective arenas. So, the flower shaped nanoparticles are in focus nowadays due to their enhanced electrocatalytic and optical properties as compared to the spherical ones. We present the biosynthesis of flower shaped gold nanoparticles by
Bacillus subtilis
RSB64 and process parameters optimization using central composite design. The two well-separated scattering spectra showing absorption peaks at 540 nm and 750 nm indicate the presence of anisotropic gold nanoparticles and the results were corroborated by transmission electron microscopy analysis. The presence of gold nanoparticles was further confirmed by energy dispersive X-ray studies. The functional groups responsible for the stability of gold nanoparticles were predicted by Fourier transform infrared spectroscopy. The gold nanoparticles biosynthesis were collective effects of three experimental process parameters viz pH, temperature and precursor concentration. These three parameters were statistically optimized wherein pH 11.0, substrate concentration 1:1 (v/v) and temperature of 50 °C resulted in the synthesis of stable flower shaped gold nanoparticles of 50 nm size. The results indicated the tailored biosynthesis of gold nanoparticles with a flower like morphology by multi process parameter analysis to finalize robust conditions for the synthesis using
B. subtilis
RSB64. These gold nanoflowers demonstrate increased surface area efficiency/reactivity and could be employed for sustained and controlled delivery of drugs.
Sorghum (
L.) is one of the world's most important cereal crops grown for multiple applications and has been identified as a potential biofuel crop. Despite several decades of study, sorghum has been ...widely considered as a recalcitrant major crop for transformation due to accumulation of phenolic compounds, lack of model genotypes, low regeneration frequency and loss of regeneration potential through sub-cultures. Among different explants used for genetic transformation of sorghum, immature embryos are ideal over other explants. However, the continuous supply of quality immature embryos for transformation is labour intensive and expensive. In addition, transformation efficiencies are also influenced by environmental conditions (light and temperature). Despite these challenges, immature embryos remain the predominant choice because of their success rate and also due to non-availability of other dependable explants without compromising the transformation efficiency.
We report here a robust genetic transformation method for sorghum (Tx430) using differentiating embryogenic calli (DEC) with nodular structures induced from immature embryos and maintained for more than a year without losing regeneration potential on modified MS media. The addition of lipoic acid (LA) to callus induction media along with optimized growth regulators increased callus induction frequency from 61.3 ± 3.2 to 79 ± 6.5% from immature embryos (1.5-2.0 mm in length) isolated 12-15 days after pollination. Similarly, the regeneration efficiency and the number of shoots from DEC tissue was enhanced by LA. The optimized regeneration system in combination with particle bombardment resulted in an average transformation efficiency (TE) of 27.2 or 46.6% based on the selection strategy, 25% to twofold higher TE than published reports in Tx430. Up to 100% putative transgenic shoots were positive for
-
by PCR and 48% of events had < 3 copies of transgenes as determined by digital droplet PCR. Reproducibility of this method was demonstrated by generating ~ 800 transgenic plants using 10 different gene constructs.
This protocol demonstrates significant improvements in both efficiency and ease of use over existing sorghum transformation methods using PDS, also enables quick hypothesis testing in the production of various high value products in sorghum.
The nanoplasmonic impact of chemically synthesized Au nanoparticles (Au NPs) on the performance of GaN nanostructure-based ultraviolet (UV) photodetectors is analyzed. The devices with uniformly ...distributed Au NPs on GaN nanostructures (nanoislands and nanoflowers) prominently respond toward UV illumination (325 nm) in both self-powered as well as photoconductive modes of operation and have shown fast and stable time-correlated response with significant enhancement in the performance parameters. A comprehensive analysis of the device design, laser power, and bias-dependent responsivity and response time is presented. The fabricated Au NP/GaN nanoflower-based device yields the highest photoresponsivity of ∼ 380 mA/W, detectivity of ∼ 1010 jones, reduced noise equivalent power of ∼ 5.5 × 10–13 W Hz–1/2, quantum efficiency of ∼ 145%, and fast response/recovery time of ∼40 ms. The report illustrates the mechanism where light interacts with the chemically synthesized nanoparticles guided by the surface plasmon to effectively enhance the device performance. It is observed that the Au NP-stimulated local surface plasmon resonance effect and reduced channel resistance contribute to the augmented performance of the devices. Further, the decoration of low-dimensional Au NPs on GaN nanostructures acts as a detection enhancer with a fast recovery time and paves the way toward the realization of energy-efficient optoelectronic device applications.
Purpose: Retinopathy of prematurity (ROP) is a leading cause of childhood blindness. Capturing serial daily postnatal weight gain can act as an innovative, low-cost method of risk stratification. We ...aim to study the relation between weight gain in infants and occurrence of ROP. Methods: The prospective, observational study was conducted on 62 infants. ROP screening was done based on the Rashtriya Bal Swasthya Karyakram (RBSK) criteria. Infants were classified into no ROP (n = 28), mild ROP (n = 8), and treatable ROP (n = 26) groups. Average daily postnatal weight gain was measured and its relation to development of ROP was studied. All statistical calculations were done using Statistical Package for the Social Sciences (SPSS) 21 version (SPSS Inc., Chicago, IL, USA) statistical program for Microsoft Windows. Results: Mean rate of weight gain in no ROP group, mild ROP group, and treatable ROP group was 33.12, 27.19, and 15.31 g/day, respectively (P = 0.001). Mean gestational age and birth weight in treatable group (n = 26) were 31.38 weeks and 1572.31 g, respectively. Receiver operating curve analysis revealed a cutoff of 29.33 g/day for ROP and 21.91 g/day for severe ROP. Conclusion: We concluded that, babies with poor weight gain of below 29.33 g/day are at high risk for ROP and babies with wight gain of 21.91 g/day are at high risk for severe ROP. These babies should be followed meticulously. So, the rate of weight gain of a preterm can help us to prioritize babies.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
DNA based nanostructures provide a versatile foundation because they exhibit fascinating luminescent and detection properties. Among such DNA nanostructures, DNA assembled fluorescent metal ...nanoclusters (NCs), such as silver (Ag), gold (Au) and copper (Cu) nanoclusters, as a new class of fluorophore have attracted progressively more attention owing to their unique electronic structures and the subsequent unusual physical and chemical properties. These excellent properties make them ideal luminescent probes for bio-chemical applications. Blending of metal with DNA sequences as a stabilizing agent has generated a large number of biosensors, as well as imaging and catalytic properties. To date, significant efforts have been devoted to the synthesis, properties and application studies of DNA hosted Au, Ag and Cu NCs. In this review article, we focus on summarizing recent advances in controllable synthesis of DNA, nucleotide-templated NCs strategies and emerging applications of metal NCs, including Au, Ag and Cu. Finally, we conclude with the enduring goal of this area of research, which could explore as novel promisingly environmental-benign approaches to construct nano clusters through DNA-based conjugation and modulation.
In this review, we have discussed the emergence of promising environmental-benign DNA assembled fluorescent metal nanoclusters and their unique electronic structures, unusual physical and chemical properties.
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