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In this work, we fabricated a highly efficient and reabsorption-free transparent X-ray imaging scintillator with high performance using an efficient triplet-triplet energy transfer strategy between thermally activated delayed fluorophore (TADF-Br) and iridium organometallic complex (Ir-OMC). Steady-state and ultrafast time-resolved experiments—supported by high-level density functional theory calculations—clearly demonstrate that efficient triplet-triplet energy transfer from TADF-Br with a high X-ray absorption cross-section to emissive Ir-OMC can be achieved. Such high efficiency of interfacial triplet energy transfer and the heavy atoms in both the donor and acceptor led to a remarkable enhancement in triplet-state radioluminescence upon X-ray irradiation. The fabricated X-ray imaging scintillator achieved an X-ray imaging resolution of 19.8 lp mm−1, exceeding the resolution of most reported organic and organometallic scintillation screens.

Sales force compensation models are often constrained by the assumption that salesperson effort is unidimensional. Some models have extended this scenario to multiple products but retain the 'single-effort' assumption. In addition, salesperson efficiency has been ignored. As selling is clearly multidimensional, we present a formulation of an agency model (MIPAM) that incorporates multidimensional sales effort as well as salesperson efficiency. Using the model, we also show that under certain assumptions, we can build the second-order condition of the agent's maximization into the principal-agent problem, instead of assuming it, as has been done in the past., Traditionally, firms have compensated their sales representatives using an individual performance model (e.g., Basu et al. 1985; Rao 1990). In these models, agency-theoretic approaches have been widely used to develop [...]

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 O2, 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/cm2) 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 catalytic utility of [RuL1(CO)2I2] (1), containing an annelated π-conjugated imidazo-naphthyridine-based mesoionic carbene (MIC) ligand (L1), is evaluated for E-selective alkyne semihydrogenation. The precatalyst 1, in combination with 2 equiv of AgBArF, semihydrogenates a broad range of internal alkynes with molecular hydrogen (5 bar) in water. (E)-Alkenes are accessed in high yields, and a number of reducible functional groups are tolerated. A chelate MIC ligand and two ciscarbonyls provide a well-defined platform at the Ru center for hydrogenation and isomerization. The loss of two iodides and the presence of two carbonyls render the Ru center electron deficient and thus the formation of metal vinylidenes with terminal alkynes is avoided. This is leveraged for the semihydrogenation of terminal alkynes by the same catalytic system in isopropyl alcohol. Reaction profile, isomerization, kinetic, and DFT studies reveal initial alkyne hydrogenation to a (Z)-alkene, which further isomerizes to an (E)-alkene via metal-catalyzed Z→ Eisomerization.

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.

This clinical record revisits the classical and pathognomonic features of craniocervical tetanus in a 65-year-old farmer who presented with acute-onset trismus, multiple cranial nerve pareses (III, IX, and X), risus sardonicus, and spasm of the head–neck musculature. This paper explores the relevant literature and presents a brief pictorial analysis of the global epidemiologic data. With most countries successfully adopting the maternal and neonatal tetanus elimination (MNTE) program, the incidence and mortality of tetanus across age groups have sharply reduced in high-income and most middle-income nations. In adults, tetanus is now encountered in specialized situations like waning immunity and incomplete vaccination, in the resource-poor and low-income nations, in countries achieving MNTE recently, and as cluster cases in the aftermath of natural disasters involving human settlements. Therefore, present-day practicing otolaryngologists and residents who have limited exposure to the tell-tale clinical features of craniocervical tetanus should consider it during work-up of acute-onset trismus in adults in susceptible situations and with a conducive background. The clinical spectrum of craniocervical tetanus as depicted in this report, including the demonstration of the pathognomonic positive spatula test, provides valuable learning points for otolaryngologists in this regard.

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 H2.

Alcohols are unreactive and require strong inorganic oxidants to convert to synthetically useful carbonyl compounds. Acceptorless dehydrogenation of alcohol is a green and atom-economic alternative, which provides aldehyde (or ketone) without the use of sacrificial acceptor molecules and the side product is molecular hydrogen. This review provides a brief overview of the initial work followed by recent advances in the field of acceptorless alcohol dehydrogenation. Catalysts that employ metal–ligand cooperation for alcohol activation and dehydrogenation are covered in details. Different mechanisms are examined and clear advantages associated with a bifunctional pathway are outlined. Mechanistic understanding at the molecular level helps to develop new generation dehydrogenation catalysts. Recent works from our group on this area along with literature reports are discussed.

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. 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. 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. 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.

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.