A facile route has been developed to synthesise and isolate sulphur doped fluorescent carbon dots for the first time. Such carbogenic quantum dots exhibit a wide band gap of 4.43 eV with a high open circuit voltage (V OC ) of 617 mV along with a fill factor (FF) as high as 37%, using phenyl-C60-butyric acid methyl ester (PCBM) as the electron transporting layer. Besides the wide band gap, which is useful in the fabrication of solar cells, sulphur modified carbon dots also exhibit a high fluorescence quantum yield of 11.8% without any additional surface passivation, producing a unique fluorescent probe for further applications. In addition, the particles have a strong tendency to interact with the surface of gold nanoparticles and produce a thin fluorescent layer over their surfaces. Moreover, as they are completely biocompatible in nature, the highly fluorescent S-doped carbon dots have a strong potential for use in bioimaging applications. Interestingly, owing to the presence of oxygen and sulphur functionality, the highly negatively charged particles can easily bind with positively charged DNA-PEI complexes, simply by mixing them, and after interaction with DNA, bright blue fluorescence has been observed under an excitation wavelength of 405 nm .

Jute (Corchorus sp.) is one of the most important sources of natural fibre, covering ∼80% of global bast fibre production1. Only Corchorus olitorius and Corchorus capsularis are commercially cultivated, though there are more than 100 Corchorus species2 in the Malvaceae family. Here we describe high-quality draft genomes of these two species and their comparisons at the functional genomics level to support tailor-designed breeding. The assemblies cover 91.6% and 82.2% of the estimated genome sizes for C. olitorius and C. capsularis, respectively. In total, 37,031 C. olitorius and 30,096 C. capsularis genes are identified, and most of the genes are validated by cDNA and RNA-seq data. Analyses of clustered gene families and gene collinearity show that jute underwent shared whole-genome duplication ∼18.66 million years (Myr) ago prior to speciation. RNA expression analysis from isolated fibre cells reveals the key regulatory and structural genes involved in fibre formation. This work expands our understanding of the molecular basis of fibre formation laying the foundation for the genetic improvement of jute.

The isolation and complete characterization of a new bis-azoaromatic ligand, 2,6-bis(phenylazo)pyridine (L), are described, and its coordination to iron(II) is reported. A pseudo-trigonal-bipyramidal mixed-ligand complex of iron(II), FeLCl2 (1), and a homoleptic octahedral iron complex, mer-[Fe(L)2]ClO4 [2]ClO4, have been synthesized from L and FeCl2 or hydrated Fe(ClO4)2, respectively, in boiling methanol. Determination of the X-ray crystallographic structure together with magnetic data (≈ 5.06 μB) and Mössbauer analysis of 1 established a high-spin Fe(II) complex ligated by one neutral 2,6-bis(phenylazo)pyridine ligand. The X-ray crystallographic structure (showing dN-N > 1.30 Å), Mössbauer data, and magnetic susceptibility measurements (≈ 1.65 μB) as well as a nearly isotropic EPR signal with only a small metal contribution at g = 1.968, on the other hand, suggest a low-spin Fe(II) complex with a one-electron-reduced radical ligand coordination in [2]ClO4. The ligand and the metal complexes have well-behaved redox properties, with the ligand(s) functioning as the redox-active site(s) responsible for redox events. The uncoordinated ligand, L, displays a reversible one-electron wave at -1.07 V and a quasi-reversible wave at -1.39 V. The partially reduced ligand L(•-) shows a single-line EPR spectrum at g = 2.001, signifying that L(•-) is a free radical. While complex 1 shows a reversible reduction at -0.08 V and an irreversible cathodic response at -0.98 V, the bis-chelate [2]ClO4 undergoes a reversible one-electron oxidation at 0.54 V and three successive reversible one-electron reductions at -0.18, -0.88, and -1.2 V, all occurring at the ligands without affecting the metal ion oxidation state. The electronic structures of the parent monocationic complex [2](+) and its oxidized and reduced forms, generated by exhaustive electrolyses, have been characterized by using a host of spectroscopic techniques and density functional theory (DFT). It is found that the 2,6-bis(phenylazo)pyridine ligand (L) is truly redox noninnocent and is capable of coordinating transition-metal centers in its neutral ([L](0)), monoanionic monoradical ([L(•)](-)), and dianionic diradical ([L(••)](2-)) forms.

Zinc oxide nanoparticle (ZNP) has been synthesized by microwave-assisted technique with the aid of a buffer solution. ZNP inhibited the growth of bacterial system Escherichia coli, even its multidrug-resistant counterpart as well. Systematic evaluation reveals that bioavailable crystalline ZNP damages the lipopolysaccharide layer from outer membrane (OM) of E. coli, subsequently damages the OM followed by inner membrane, enters within the cell and generates extensive reactive oxygen species-mediated damage. A series of biochemical, biophysical and molecular techniques have been used to reach the conclusion. We believe this work is expected to enlighten the detailed mode of action study in bacterial system.

Mung bean plants were grown under controlled conditions and supplemented with macro- and micronutrients. The objective of this study was to determine the response of manganese nanoparticles (MnNP) in nitrate uptake, assimilation, and metabolism compared with the commercially used manganese salt, manganese sulfate (MS). MnNP was modulated to affect the assimilatory process by enhancing the net flux of nitrogen assimilation through NR-NiR and GS-GOGAT pathways. This study was associated with toxicological investigation on in vitro and in vivo systems to promote MnNP as nanofertilizer and can be used as an alternative to MS. MnNP did not impart any toxicity to the mice brain mitochondria except in the partial inhibition of complex II-III activity in ETC. Therefore, mitochondrial dysfunction and neurotoxicity, which were noted by excess usage of elemental manganese, were prevented. This is the first attempt to highlight the nitrogen uptake, assimilation, and metabolism in a plant system using a nanoparticle to promote a biosafe nanomicronutrient-based crop management.

A series of cobalt complexes of ligands based on the 2-(arylazo)pyridine architecture have been synthesized, and the precise structure and stoichiometry of the complexes depend critically on the identity of substituents in the 2, 4, and 6 positions of the phenyl ring. The 2-(arylazo)pyridine motif can support either Co(II) complexes with neutral ligands, Co(II)Cl2(L(a))2 (1), Co(II)Cl2(L(c))2 (3), [Co(II)Cl(L(b))2]2(PF6)2 (5[PF6]2), or Co(III) complexes of reduced 2-(arylazo)pyridine ligand radical anions, L(•-), Co(III)Cl(L(b•-))2 (2), Co(III)Cl(L(c•-))2 (4), and Co(III)Me(L(b•-))2 (6). All three members of the latter class are based on approximately trigonal-bipyramidal CoX(L(•-))2 architectures [L = 2-(arylazo)pyridine] with two azo nitrogen atoms and the X ligand (X = Cl or Me) in the equatorial plane and two pyridine nitrogen atoms occupying axial positions. Density functional theory suggests that the electronic structure of the Co(III) complexes is also dependent on the identity of X: the strong σ-donor methyl gives a low-spin (S = 0) configuration, while the σ/π-donor chloro gives an intermediate-spin (S = 1) local configuration. In certain cases, one-electron reduction of the Co(II)X2L2 complex leads to the formation of Co(III)X(L(•-))2; i.e., reduction of one ligand induces a further one-electron oxidation of the metal center with concomitant reduction of the second ligand.

Flooding is one of the major constraints for rice production in rainfed lowlands, especially in years and areas of high rainfall. Incorporating the Sub1 (Submergence1) gene into high yielding popular varieties has proven to be the most feasible approach to sustain rice production in submergence-prone areas. Introgression of this QTL into popular varieties has resulted in considerable improvement in yield after flooding. However, its impact under non-flooded conditions or years have not been thoroughly evaluated which is important for the farmers to accept and adopt any new version of their popular varieties. The present study was carried out to evaluate the effect of Sub1 on grain yield of rice in different genetic backgrounds, under non-submergence conditions, over years and locations. The study was carried out using head to head trials in farmer’s fields, which enable the farmers to more accurately compare the performance of Sub1 varieties with their recurrent parents under own management. The data generated from different head to head trials revealed that the grain yield of Sub1 varieties was either statistically similar or higher than their non-Sub1 counterparts under non-submergence conditions. Thus, Sub1 rice varieties show no instance of yield penalty of the introgressed gene.

This work reports the results of our investigation on the aerial oxidation of aromatic amines that are promoted by protic acid. While primary aromatic amines produce substituted phenazines as major products, N-phenyl-o-phenylenediamine produces polycyclic aromatic heterocycles like azaacene and secondary and tertiary amines give exclusively the dyes containing a triphenylmethane moiety. Isolation of the compounds and the effects of substitutions on the aromatic rings have been investigated. In this context, plausible reaction steps that are involved have been discussed. Single-crystal X-ray structure analyses of the representative compounds are solved to authenticate their formation. In almost every case, a high degree of delocalization of electron was noted. The compounds have been characterized thoroughly and show rich spectral properties. For example, the phenazine molecules exhibited absorption peaks between 475 and 605 nm because of the charge-transfer transition from the amine and tricyclopyrazine moiety. Their acidochromic and solvatochromic behaviors, which are supported by theoretical calculations, are investigated. The polycyclic azacene molecule exhibits strong absorption in the visible region and fluoresces with high quantum yield. The phenazine dyes undergo a quasi-reversible reduction at a low cathodic potential that varies linearly as a function of Hammett's constant.