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Formic acid (FA) has emerged as a promising candidate for hydrogen energy storage due to its favorable properties such as low toxicity, low flammability, and high volumetric hydrogen storage capacity under ambient conditions. Recent analyses have suggested that FA produced by electrochemical carbon dioxide (CO 2 ) reduction reaction (eCO 2 RR) using low-carbon electricity exhibits lower fugitive hydrogen (H 2 ) emissions and global warming potential (GWP) during the H 2 carrier production, storage and transportation processes compared to those of other alternatives like methanol, methylcyclohexane, and ammonia. eCO 2 RR to FA can enable industrially relevant current densities without the need for high pressures, high temperatures, or auxiliary hydrogen sources. However, the widespread implementation of eCO 2 RR to FA is hindered by the requirement for highly stable and selective catalysts. Herein, the aim is to explore and evaluate the potential of catalyst engineering in designing stable and selective nanostructured catalysts that can facilitate economically viable production of FA., (© 2024 Wiley‐VCH GmbH.)

The highly efficient reductive amination of aldehydes with ammonia (NH 3 ) and hydrogen (H 2 ) to form secondary imines is described, as well as the dehydrogenative homocoupling of benzyl amines. Using an air-stable, well-defined PN 3 -manganese(II) pincer complex as a catalyst precursor, various aldehydes are easily converted directly into secondary imines using NH 3 as a nitrogen source under H 2 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.

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., (© 2022 John Wiley & Sons Ltd.)

Well-defined and air-stable PN 3 -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.

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.

Water oxidation is a primary step in natural as well as artificial photosynthesis to convert renewable solar energy into chemical energy/fuels. Electrocatalytic water oxidation to evolve O 2 , utilizing suitable low-cost catalysts and renewable electricity, is of fundamental importance considering contemporary energy and environmental issues, yet it is kinetically challenging owing to the complex multiproton/electron transfer processes. Herein, we report the first cobalt-based pincer catalyst for catalytic water oxidation at neutral pH with high efficiency under electrochemical conditions. Most importantly, ligand (pseudo)aromaticity is identified to play an important role during electrocatalysis. A significant potential jump (∼300 mV) was achieved toward a lower positive value when the aromatized cobalt complex was transformed into a (pseudo)dearomatized cobalt species. The dearomatized species catalyzes the water oxidation reaction to evolve oxygen at a much lower overpotential (∼340 mV) on the basis of the onset potential (at a current density of 0.5 mA/cm 2 ) of catalysis at pH 10.5, outperforming other Co-based molecular catalysts reported to date. These observations may provide a new strategy for the judicious design of earth-abundant transition-metal-based water oxidation catalysts.

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., (© 2019 S. Karger AG, Basel.)

Competing Interests: There are no conflicts of interest.

A ruthenium(II) complex bearing a naphthyridine-functionalized pyrazole ligand catalyzes oxidant-free and acceptorless selective double dehydrogenation of primary amines to nitriles at moderate temperature. The role of the proton-responsive entity on the ligand scaffold is demonstrated by control experiments, including the use of a N-methylated pyrazole analogue. DFT calculations reveal intricate hydride and proton transfers to achieve the overall elimination of 2 equiv of H 2 .

The Ni II complex 1 containing pyridyl- and hydroxy-functionalized N-heterocyclic carbenes (NHCs) is synthesized and its catalytic utility for the selective nitrile hydration to the corresponding amide under base-free conditions is evaluated. The title compound exploits a hemilabile pyridyl unit to interact with a catalytically relevant water molecule through hydrogen-bonding and promotes a nucleophilic water attack to the nitrile. A wide variety of nitriles is hydrated to the corresponding amides including the pharmaceutical drugs rufinamide, Rifater, and piracetam. Synthetically challenging α-hydroxyamides are accessed from cyanohydrins under neutral conditions. Related catalysts that lack the pyridyl unit (i.e., compounds 2 and 4) are not active whereas those containing both the pyridyl and the hydroxy or only the pyridyl pendant (i.e., compounds 1 and 3) show substantial activity. The linkage isomer 1' where the hydroxy group is bound to the metal instead of the pyridyl group was isolated under different crystallization conditions insinuating a ligand hemilabile behavior. Additional pK a measurements reveal an accessible pyridyl unit under the catalytic conditions. Kinetic studies support a ligand-promoted nucleophilic water addition to a metal-bound nitrile group. This work reports a Ni-based catalyst that exhibits functional hemilability for hydration chemistry., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background and Objectives: Leiomyoma of uterus forms the most common type of benign tumor of uterus and also the most common pelvic tumor in women. The symptomatology continues to be variable. Surgery has for long been the main mode of therapy for the myomas. For women who wish to retain the uterus for future pregnancies or other reasons, myomectomy is preferred. Recent trend has been toward nonsurgical approaches like GnRH hormone analogs/agonists, RU 486, or selective uterine artery embolization, laparoscopic cryoablation, radiofrequency thermal ablation, and MRGUs. This multicentric study was an attempt to analyze the clinicopathological spectrum in cases of leiomyoma of the uterus at Cheluvamba Hospital, Adichunchanagiri Institute of Medical Sciences, and to know regarding the pattern of presentation, pathological correlation, with type of fibroid, and endometrial and ovarian changes., Methods: A clinical study of 100 cases of fibroid uterus was conducted in the Cheluvamba Hospital, attached to Mysore Medical College and Research Institute, Mysore, and Adichunchanagiri Institute of medical sciences, BG Nagara, Mandya from November 2008 to August 2012. The cases are selected by random allocation. On admission, detailed history, clinical examination, and investigations were recorded., Results: Leiomyoma is the most common benign tumor of the uterus and commonly affects the women of child-bearing age, most commonly in the third decade, 55 %. The most common mode of presentation was menstrual disturbances (76 %), among which menorrhagia was seen in 54 % of the cases. Primary infertility was seen in 15 % of the patients. Intramural fibroids were the most common variety occurring in 60 % of the cases. Endometrial pattern was proliferative in 66.3 %. Cystic ovaries were seen in 8 % of the patients, adenomyosis in 16 % indicating hyperestrogenism., Conclusion: Fibromyoma (leiomyoma) is the most common benign tumor of the pelvis. It commonly affects the women of child-bearing age, mostly in the third decade and is most commonly seen in multipara. The most common mode of presentation is menstrual disturbances. Intramural fibroid is the most common variety. The proliferative and hyperplastic endometrium was commonly reported. The presence of proliferative endometrium, adenomyosis, and cystic ovaries all are indicative of hyperestrogenic state associated with development of fibroids., Competing Interests: Maitri Raghavendra Kulkarni, Indranil Dutta, Dilip Kumar Dutta declare that they have no conflicts of interest. Informed consent All procedure followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2008. Informed consent was obtained from all patients for being included in the study.

To find out the safety, effectiveness and tolerability of using desogestrel (75 microg/day), a progesterone only pill on lactating mother, a prospective clinical study was undertaken among 200 lactating women during the period from 1st January 2010 to 13th June 2011 at Gice Clinic, Kalyani, Nadia, West Bengal. The same number of cases were taken as placebo for comparison. Desogestrel was started after six weeks of delivery for six months. Patients were reviewed at 8th, 12th, 16th, 24th weeks and one year. The very interesting results were found from the follow-up study that desogestrel (75 microg/day) did not alter the amount and composition of breast milk, pregnancy was not reported as compared to placebo. The drug had good tolerability, less side-effects and did not affect the growth and development of breastfed babies. Due to the safety, good efficacy, tolerability and less side-effects it is concluded that desogestrel (75 microg/day) was well accepted in majority of women (97.5%) and provided good contraceptive efficacy during the lactating period. This treatment does not have any effect on the growth and development of breastfed baby.

This is a review on the transition from our empirical approach to treat ovarian cancer to a specific treatment based on molecular signature. We have reviewed not only the evidence-based medicine focused on the origin and tumor morphology of ovarian cancer but also the molecular signature era based on molecular phenotyping of the tumor and its microenvironment, which influences the direct targeted therapy. Evidence-based medicine has shown that the targeted therapy studies are mainly biomarker driven, more focused, and hence treat only those patients who have the underlying molecular abnormality. This molecular abnormality is the target of the drug, leading to higher rates of response. These findings will carry important implications for screening, detection, and treatment of ovarian cancer in the future.

In a recent paper in this journal Abasolo and Tsuchiya [Abasolo, I., Tsuchiya, A., 2004. Exploring social welfare functions and violation of monotonicity: an example from inequalities in health. Journal of Health Economics 23, 313-329] have strongly argued for the use of a non-monotonic health related social welfare function. This note discusses both the limitations of the measure proposed by Abasolo and Tsuchiya [Abasolo, I., Tsuchiya, A., 2004. Exploring social welfare functions and violation of monotonicity: an example from inequalities in health. Journal of Health Economics 23, 313-329] and the problems associated with their empirics. We are able to show how non-monotonicity may lead to paradoxical results and policies. Further we examine the empirics of Abasolo and Tsuchiya [Abasolo, I., Tsuchiya, A., 2004. Exploring social welfare functions and violation of monotonicity: an example from inequalities in health. Journal of Health Economics 23, 313-329] and provide an alternative explanation to the observed patterns in the data that do not violate monotonicity. Finally we briefly mention why the Atkinson-Sen framework may be more appropriate as a way forward.