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Electrocatalytic hydrogen evolution reaction (eHER) is crucial in addressing the growing global energy demand. Although nickel‐pincer‐based molecular complexes, varying in donor atoms, were studied previously for eHER, the impact of variations in the substituents attached to the donor atoms was not investigated. Herein, three air‐stable R1PN3PR2‐based NiII–pincer complexes [R1=R2=Ph2 (7); R1=R2=tBu2 (9); R1=tBu2, R2=Ph2 (10)], varying solely in P‐substituents, were studied in acetonitrile. While the redox potentials for NiII/I and NiI/0 couples underwent anodic shifts by ~100 mV upon progressively substituting tert‐butyl by phenyl groups on each P‐atom, the corresponding eHER reactivity with organic acids (acetic acid, p‐toluenesulfonic acid and trifluoromethanesulfonic acid) of different strengths followed different trends; likely influenced by the pKa of intermediate metal‐hydride (M–H) species [pKa(M–H9)>pKa(M–H10)>pKa(M–H7)]. Depending on the acid strength, different oxidation states of the metal were activated to promote eHER. The catalytic rates for 9, 10, and 7 were calculated to be 85 s−1, 77 s−1 and 95 s−1 with Faradaic efficiencies of 88.5±2 %, 66.1±1.4 %, and 91.7±1.5 % respectively, in acetic acid. Electrochemical data supported by theoretical results reinforce a significant electronic influence of the anchoring P‐substituents on the activity of these complexes. [ABSTRACT FROM AUTHOR]

The N‐formylation of amines using CO2 hydrogenation, conducted under additive‐free conditions, represents a crucial methodology in organic synthesis. Herein, we demonstrated a highly efficient ruthenium pincer complex for the selective conversion of a wide array of amines into their corresponding formamides under additive‐free condition with a turnover number (TON) of 980,000 within a single‐batch. Controlled studies suggested the initial reduction of CO2 to ammonium formate, followed by dehydration to generate formamide. NMR experiments revealed the potential intermediates and indicated the involvement of metal‐ligand cooperativity of catalyst during substrate activation. In addition, this methodology was examined to establish a carbon neutral hydrogen storage cycle by capitalizing on the reversible transformation of formamides. [ABSTRACT FROM AUTHOR]

The growing emphasis on sustainable chemistry has driven research into utilizing carbon dioxide (CO2) as a nontoxic, abundant, and cost‐effective C1 building block. CO2 offers a promising avenue for direct conversion into valuable chemicals ranging from fuels to pharmaceuticals. This review focuses on the utilization of CO2 for reductive N‐formylation/N‐methylation reactions of various amines, providing advantages over conventional methods involving toxic CO and other methylating reagents. The approach employs readily available reductants such as silane, borane reagents, and hydrogen (H2). The discussion encompasses recent developments in transition metal and organocatalyst systems for these reactions, highlighting mechanistic interpretations and factors influencing product selectivity. [ABSTRACT FROM AUTHOR]

The highly efficient reductive amination of aldehydes with ammonia (NH3) and hydrogen (H2) to form secondary imines is described, as well as the dehydrogenative homocoupling of benzyl amines. Using an air-stable, well-defined PN3-manganese(II) pincer complex as a catalyst precursor, various aldehydes are easily converted directly into secondary imines using NH3 as a nitrogen source under H2 in a one-pot reaction. Importantly, the same catalyst facilitates the dehydrogenative homocoupling of various benzylamines, exclusively forming imine products. These reactions are conducted under very mild conditions, without the addition of any additives, yielding excellent selectivities and high yields of secondary imines in a green manner by minimizing wastes. [ABSTRACT FROM AUTHOR]

This study investigates the phonetic outcome of mixed-language speech in Bengali and Indian English, towards understanding cross-language interaction in highly proficient bilinguals. We compare spectral properties of L2 vowels [æ] (common to L1, L2) and [ʌ] (absent in L1) in code-switched (mixed) vs. nonswitched productions. Results reveal asymmetrical shifts in both vowels during mixed productions, towards related L1 categories. We interpret this as a temporary increase in cross-language phonetic interaction during mixed-language use, leading to a shift towards L1 norms, evidencing transfer effects on L2 vowels. We elicit mixed productions through two tasks: cued picture-naming and code-switching, to assess if experimental paradigm independently influences the behavior under study. Results reveal parallel patterns, but small magnitude differences, across paradigms. We discuss these findings in light of recent proposals about asymmetries in short-term phonetic interaction, postulated discursive factors in code-switching, and the issue of comparability between paradigms in transfer studies. [ABSTRACT FROM AUTHOR]

A wide range of desirable properties has made formic acid (FA) a favored liquid organic hydrogen carrier in recent years. The state-of-the-art homogenous catalysts generally require a base as an additive in a certain solvent to promote FA dehydrogenation. However, it is crucially important to carry out the reaction without the use of a solvent or any volatile additive in order to achieve optimal efficiency in the process. Herein, we report a series of iridium compounds having an azocarboxamide ligand backbone capable of decomposing FA exclusively into H2 and CO2 without the need to use solvents or volatile additives. Under the optimized reaction conditions, a maximum TOF of 12,500 h-1 was achieved with no formation of CO. [ABSTRACT FROM AUTHOR]

Dual practice, where physicians work both in public and private hospitals, is a widely observed phenomenon, particularly in developing countries. This paper studies a multi-stage game where hospitals compete for physicians as well as patients and, the service provided by physicians endogenously depends on the competitive setting in which hospitals operate. Specifically, we examine the impact of allowing dual practice on hospital payoffs, physician's service and societal welfare. We find that dual practice is socially desirable, since it softens the competition for physician's exclusive service while also increasing the amount of their service. However, if the degree of competition between the hospitals is significant, dual practice may not yield the highest payoffs for both public and private hospitals. [ABSTRACT FROM AUTHOR]

Byline: Indranil. Dutta, Guruaribam. Sharma, Khungdombam. Singh Sir, A very few case reports were done in the literature about transsphenoidal encephalocele (TSE) with colpocephaly and corpus callosum agenesis in a [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jhealeco.2006.11.002 Byline: Indranil Dutta (a)(b) Keywords: Health inequality; Non-monotonicity; Social welfare function Abstract: This rejoinder demonstrates that the arguments made in AT (2006) are not robust and the case against non-monotonic HRSWF and their empirics remain overwhelming. Author Affiliation: (a) UNU-WIDER, Helsinki, Finland (b) Department of Economics, University of Sheffield, Sheffield, UK Article History: Received 1 November 2006; Accepted 14 November 2006

The storage and utilization of low‐carbon electricity and decarbonization of transportation are essential components for the future energy transition into a low‐carbon economy. While hydrogen has been identified as a potential energy carrier, the lack of viable technologies for safe and efficient storage and transportation of H2 greatly limits its applications and deployment at scale. Formic acid (FA) is considered one of the promising H2 energy carriers because of its high volumetric H2 storage capacity of 53 g H2/L, and relatively low toxicity and flammability for convenient and low‐cost storage and transportation. FA can be employed to generate electricity either in direct FA fuel cells (FCs) or indirectly as an H2 source for hydrogen FCs. FA can enable large‐scale chemical H2 storage to eliminate energy‐intensive and expensive processes for H2 liquefaction and compression and thus to achieve higher efficiency and broader utilization. This perspective summarizes recent advances in catalyst development for selective dehydrogenation of FA and high‐pressure H2 production. The advantages and limitations of FA‐to‐power options are highlighted. Existing life cycle assessment (LCA) and economic analysis studies are reviewed to discuss the feasibility and future potential of FA as a fuel. [ABSTRACT FROM AUTHOR]

Well-defined and air-stable PN3–pincer manganese(II) complexes were synthesized and used for the hydrogenation of aldehydes into alcohols under mild conditions using MeOH as a solvent. This protocol is applicable for a wide range of aldehydes containing various functional groups. Importantly, α,β-unsaturated aldehydes, including ynals, are hydrogenated with the C＝C double bond/C≡C triple bond intact. Our methodology was demonstrated for the conversion of biomass derived feedstocks such as furfural and 5-formylfurfural to furfuryl alcohol and 5-(hydroxymethyl)furfuryl alcohol respectively. [ABSTRACT FROM AUTHOR]

Background: Maternal Mortality is one of the most important issues in our country. Ectopic Gestation is one of the few reasons which contribute to it. The first successful surgical management of a tubal ruptured ectopic pregnancy occurred in 1883. In those times mortality was approximately 60%. Since then lot of development in management of ectopic pregnancy has taken place which has resulted in reduction of related mortality. But still it remains as one of the important topics as now due to more infections (i.e PID) and resulting ectopic gestations and further operative salphingectomies, there is a reduced chance of patient to conceive naturally afterwards. Hence role of conservative surgeries comes to the front. Aims and Objectives: Role of Conservative Surgical Management of Ectopic pregnancy and its relation to future fertility. Materials and Methods: This Study was undertaken at GICE Clinic, Cure Hospital, Kalyani, West Bengal India from January, 2008 to January 2019. During this period 64 patients were diagnosed and operated for Ectopic pregnancy. Results: Forty (62.5%) cases were in between 20-30 years of age. Forty-four (68.7%) cases had no issue. Forty-eight (75.0%) cases were from low socio-economic group. Sixty patients (93.7%) had the history of amenorrhea. It was also observed that history of induced abortion was in 20 (31.2%) cases, PID in 12 (18.7%) cases, appendectomy -- 6 (9.4%) cases and history of previous IUCD insertion - 4 (6.3%) were found to be common amongst ectopic gestation cases. Twenty-four (37.5%) cases underwent linear salpingostomy, 8 (12.5%) cases had segmental resection with end to end anastomosis whereas 16 (25.0%) cases had salpingectomy and 16 (25.0%) cases had salpingo-opherectomy with tubectomy [opposite tube] were advocated. In 4(6.3%) cases of linear salpingostomy and 4 (6.3%) cases of segmental resection, the cases had to be re-operated again for unstable haemodynamic condition within 24 hours and were subsequently advocated to salpingectomy. Conclusion: Linear Salpingostomy was found to be a better option for women who desire to become future mother, than that of segmental resection and salpingectomy on affected tube (although pregnancy was reported as opposite tube) [ABSTRACT FROM AUTHOR]

Unlike the conventional model of transition metal catalysis, ligands in metal–ligand cooperative (or bifunctional) catalysis are involved in the substrate activations. Such processes have offered unique mechanistic understandings and led to new concepts for the catalyst design. In particular, unprecedented activities were discovered when the ligand could undergo dearomatization–rearomatization reactions during the catalytic cycle. Aromatization can provide an extra driving force to thermodynamics; consequently, it brings a new perspective to ligand platform design for catalysis. While numerous applications were demonstrated, the influences of changing ligand aromatic properties were often overlooked. In this article, representative ligand systems will be highlighted and a comparison between the Milstein and the Huang pincer systems will be discussed to provide theoretical and conceptual insights. [ABSTRACT FROM AUTHOR]

This chapter is a short thematic introduction to the papers that appear in this special volume on the phonetics and phonology of a selective but representative set of languages from the South Asian sprachbund. The volume consists of five papers that engage with a broad set of topics, namely, acoustics of Kalasha affricates, perception of breathiness in Gujarati, syllable structure of Kuki-Chin, syllable structure and incipient vowels in Lamkang, and vowel harmony in Assamese. These papers, we hope, are representative in terms of the choice of theoretical frameworks and methodologies employed in addressing the various linguistic phenomena. [ABSTRACT FROM AUTHOR]

Adequate nutrition is generally regarded as a core dimension in any evaluation of well‐being. In the context of India, a country with a high prevalence of poor nutrition, there is a dearth of nutrition studies with adequate coverage and comparability. Using primary data on food consumption from a village in a poorer state of India, we study the consumption of five key nutrients, namely, calories, protein, carbohydrates, calcium and iron. Among the various determinants of nutrition, we find that expenditure has a significant impact on nutrition and the expenditure elasticity of nutrition is comparatively high for all the key nutrients. By correcting for potential endogeneity, we demonstrate a causal link from expenditure and food subsidy provided by the public distribution system to nutritional intake. There is some evidence that household characteristics such as household size and gender of the household head matter for nutrition; however, they are not robust under various specifications. [ABSTRACT FROM AUTHOR]

The study examines acoustic correlates of the four-way laryngeal contrast in Marathi, focusing on temporal parameters, voice quality, and onset f0. Acoustic correlates of the laryngeal contrast were investigated in the speech of 33 native speakers of Marathi, recorded in Mumbai, India, producing a word list containing six sets of words minimally contrastive in terms of laryngeal specification of word-initial velar stops. Measurements were made for the duration of prevoicing, release, and voicing during release. Fundamental frequency was measured at the onset of voicing following the stop and at 10 additional time points. As measures of voice quality, amplitude differences between the first and second harmonic (H1–H2) and between the first harmonic and the third formant (H1–A3) were calculated. The results demonstrated that laryngeal categories in Marathi are differentiated based on temporal measures, voice quality, and onset f0, although differences in each dimension were unequal in magnitude across different pairs of stop categories. We conclude that a single acoustic correlate, such as voice onset time, is insufficient to differentiate among all the laryngeal categories in languages such as Marathi, characterized by complex four-way laryngeal contrasts. Instead, a joint contribution of several acoustic correlates creates a robust multidimensional contrast. [ABSTRACT FROM AUTHOR]

Byline: Kalpana. Datta, Supratim. Datta, Indranil. Dutta Central pontine myelinolysis (CPM) is an acute demyelination within the central basis pontis. Though exact mechanism is not known it is seen commonly [...]