Spectral characterization and severity assessment of rice blast disease using univariate and multivariate models.

Rice is the staple food of more than half of the population of the world and India as well. One of the major constraints in rice production is frequent occurrence of pests and diseases and one of them is rice blast which often causes yield loss varying from 10 to 30%. Conventional approaches for disease assessment are time-consuming, expensive, and not real-time; alternately, sensor-based approach is rapid, non-invasive and can be scaled up in large areas with minimum time and effort.

Specific Human Capital and Skills in Indian Manufacturing: Observed Wage and Tenure Relationships from a Worker Survey.

Successive Indian governments have attempted to increase the growth in employment alongside encouraging skill enhancement. Against this background, we empirically explore issues surrounding the investment in specific capital by workers. In particular, we try to discern the presence of specific human capital investment by investigating whether there is a link between tenure and wages and find that there is indeed such a link evident in India.

Interactive effect of elevated tropospheric ozone and carbon dioxide on radiation utilisation, growth and yield of chickpea (Cicer arietinum L.).

An experiment was conducted in the Free Air Ozone and Carbon dioxide Enrichment (FAOCE) facility to study the impact of elevated O, CO and their interaction on chickpea crop (cv. Pusa-5023) in terms of phenology, biophysical parameters, yield components, radiation interception and use efficiency. The crop was exposed to elevated O (EO:60ppb), CO (EC:550 ppm) and their combined interactive treatment (ECO: EC+EO) during the entire growing season.

Mechanistic Studies on -Heterocyclic Carbene-Catalyzed Umpolung of β,γ-Unsaturated α-Diketones.

The mechanism of -heterocyclic carbene-catalyzed umpolung of β,γ-unsaturated α-diketone was studied using both density functional theory (DFT) calculations and experimental methods. In contrast to the originally proposed mechanism, the calculations revealed a more complicated process involving both nucleophilic -acylated homoenolate and electrophilic α,β-unsaturated acyl azolium intermediates. The experimental studies confirmed the existence of the aforementioned two key intermediates.

Osteochondral Defects Healing Using Extracellular Matrix Mimetic Phosphate/Sulfate Decorated GAGs-Agarose Gel and Quantitative Micro-CT Evaluation.

Tissue engineering has a major emphasis in creating tissue specific extracellular ambiance by altering chemical functionalities of scaffold materials. Heterogeneity of osteochondral tissue necessitates tailorable bone and cartilage specific extracellular environment. Carboxylate- and sulfate-functionalized glycosaminoglycans (GAGs) in cartilage extracellular matrix (ECM) create an acidic ambience to support chondrogenic activity, whereas phosphate-rich environment in bone enables chelation of calcium leading to the formation of mineralized matrix along with an alkaline environment to support osteogenesis.

Copper catalyzed photoredox synthesis of α-keto esters, quinoxaline, and naphthoquinone: controlled oxidation of terminal alkynes to glyoxals.

Herein, we report a facile visible light induced copper catalyzed controlled oxidation of terminal C[triple bond, length as m-dash]C alkynes to α-keto esters and quinoxalines formation of phenylglyoxals as stable intermediates, under mild conditions by using molecular O as a sustainable oxidant. The current copper catalysed photoredox method is simple, highly functional group compatible with a broad range of electron rich and electron poor aromatic alkynes as well as aliphatic alcohols (1°, 2° and 3° alcohols), providing an efficient route for the preparation of α-keto esters (43 examples), quinoxaline and naphthoquinone with higher yields than those in the literature reported thermal processes. Furthermore, the synthetic utility of the products has been demonstrated in the synthesis of two biologically active molecules, an DHPS inhibitor and CFTR activator, using the current photoredox process.

N-Heterocyclic Carbene-Catalyzed Umpolung of β,γ-Unsaturated 1,2-Diketones.

The umpolung of β,γ-unsaturated diketones through N-heterocyclic carbene catalysis is described, which allows access to a variety of highly functionalized bicyclic cyclohexene-β-lactones and 1,3,4-triaryl benzenes. An unprecedented reaction pattern involving the catalytic formation of nucleophilic O-acylated homoenolate intermediate is proposed. A diverse set of transformations on the product further showed the synthetic potential of this protocol.

Enantioselective intermolecular all-carbon [4+2] annulation via N-heterocyclic carbene organocatalysis.

The highly stereoselective intermolecular all-carbon [4+2] annulation between in situ generated acyclic dienolates and α,β-unsaturated acyl azoliums is disclosed. The identification of 2-acyloxy-3-butenones as suitable diene precursors is the key to the success of this transformation. The corresponding highly functionalized cyclohexene products, which are inaccessible from Diels-Alder reactions, were delivered with high levels of diastereo- and enantioselectivities.

Dynamic Kinetic Resolution Enabled by Intramolecular Benzoin Reaction: Synthetic Applications and Mechanistic Insights.

The highly enantio-, diastereo-, and regioselective dynamic kinetic resolution of β-ketoesters and 1,3-diketones was achieved via a chiral N-heterocyclic carbene catalyzed intramolecular cross-benzoin reaction. A variety of tetralone derivatives bearing two contiguous stereocenters and multiple functionalities were liberated in moderate to excellent yields and with high levels of stereoselectivity (>95% ee and >20:1 dr in most cases). In addition, the excellent regioselectivity control for aryl/alkyl 1,3-diketones, and the superior electronic differentiation of 1,3-diarylketones were highlighted.

N-Heterocyclic carbene-catalyzed desymmetrization of functionalized 1,4-dienes via Stetter Reaction.

The asymmetric desymmetrization of 1,4-dienes via chiral N-heterocyclic carbene catalyzed Stetter-type umpolung reaction was demonstrated. A variety of differently substituted dienes were tolerated very well, affording cyclic ketones with two consecutive stereogenic centers (including one quaternary carbon) in moderate to high yields and with high to excellent enantioselectivities. This work expanded both reaction types of catalytic diene desymmetrizations and substrate diversity in NHC catalyzed desymmetric transformations.