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The NiII 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 p Ka 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. [ABSTRACT FROM AUTHOR]

The reactivity and catalysis at axial sites of [Ruâ€˵Ru] bonded compounds are described. Effect of axial donor at axial site of a [Ruâ€˵Ru] single bond, having electronic configuration σ2Ï€4δ2δ*2Ï€*4, is examined. It is shown that the stronger donor leads to longer metalâ€˵metal distances. The Câ€˵H bond activation and Câ€˵C bond formation are studied at axial site of a [Ru2(CO)4]2+ core. Metalâ€˵metal and metalâ€˵ligand cooperation is exploited for catalytic alcohol dehydrogenation to aldehyde and subsequent coupling with amine to access imine selectively. Catalytic carbene transfer reactions are discussed for a wide range of diruthenium(I,I) compounds. Catalytic utility of metalâ€˵metal multiply bonded diruthenium(II,III) compounds for Câ€˵H amination reaction is also discussed. [ABSTRACT FROM AUTHOR]

Objective: The present comparative study helps in developing a new approach to conventional hysterectomy procedure so as prevent intra-operative and Post-operative complications during the procedure. Methods: Ligation of uterine and ovarian arteries was performed, prior to abdominal hysterectomy procedures, in Group A (n-1000) and conventional method of abdominal hysterectomy in Group B (n-450) from January 2000 to December 2009. It was a prospective study. Results: In Group A it was noted that traumatic injury to (L) uterine vessel was present in 4 (0.4%) cases and (R) uterine vessel in 3 (0.3%) cases without any noticeable injury to the ovarian vessels, ureters or bladder as compared to in Group B where injury to (L) uterine was noted in 11 (2.4%) cases, ureters in 1 (0.1%) case, bladder in 6(1.5%) cases, hematoma in 10 (2.2%). Post-operative complications were found to be uneventful in Group A. Conclusion: The Present study concludes that ligation of uterine and ovarian arteries, prior to conventional abdominal hysterectomy procedures is found to be extremely safe procedure thereby reducing the risk of intra-operative and post- operative complications. [ABSTRACT FROM AUTHOR]

Background: Uterine atony accounts for 80% of causes of PPH and is one of the important cause of maternal death. Objective: To analyze the efficacy of Dutta's score for early detection and management of uterine atony during emergency LSCS to prevent PPH. Study methods: This study was undertaken at JNM, NSGN, CN at Kalyani, Nadia, West Bengal India from 1st January 2007 to 31st December 2011. Three hundred cases undergoing emergency LSCS were selected for randomized trial. Clinical observations were made after placental expulsion for scoring which includes shape and size of uterus, rugosity, tone, placental localization and time of placental expulsion. Score of 0, 1, 2 were given on each observation. Three groups are created depending on scoring-Group A (130) -8 to 10, Group B (N-100) -5 to 7 and Group C (N-70) - <5 for better management. Management protocols were formulated in the three groups for prevention of PPHGroup A:- Oxytocin 10U (5U IM + 5U IV 40drops/min in Ringer Lactate 500ml) Group B:- Oxytocin 15U (5U IM + 10U IV 40drops/min in Ringer lactate 500 ml) + methyl ergometrine (0.25mg IM) + anterior posterior uterine wall compression Group C:- Oxytocin 20 U- (5U IM plus 15 U IV 40 drops in Ringer Lactate 500 ml) + methyl ergometrine (0.5mg IM) + carboprost (250 mcg IM) + lateral followed by anterior posterior uterine wall compression + compression of isthmic region of uterus + misoprostol 800mg per rectal during post operative period. Results: After adopting Dutta's score and management protocols it was interesting to observe that intra and post operative blood loss within 2hr were found to be significantly reduced in group A-69.3% (<300CC), 84.6%(<200CC) and group B-70%(<300cc), 72%(<200CC). Intra operative blood loss >500cc were also found to be reduce in group A- 7.6%, group B-14%. In group C intra operative blood loss >500cc were seen in 47.1% and post operative -32.9% cases. Hemoglobin level <11gms after 24 hrs of LSCS was found to be minimally reduced (in comparison to preoperative hemoglobin level) in group A (1.5%), group-B (2%) and group C (11.4%). Conclusion: Early diagnosis and management of uterine atony during emergency LSCS after adopting Dutta's score were found to be not only reduce intra and post operative blood loss but also was found to maintain a satisfactory hemoglobin level and hemodynamic status. Maternal mortality was found to be nil. This randomized trial highlighted the importance of prompt treatment in group C to reduce intra and post operative blood loss and maternal morbidity and mortality. [ABSTRACT FROM AUTHOR]

It is well accepted that a country's GDP may not fully reflect its level of well-being. In recent years, happiness has emerged as an alternative indicator of well-being, and research has mainly focused on determining the level of happiness. While it is important to look at the level, the distribution of happiness is also a salient aspect in any evaluation of inequality. There has been a growing interest in the distribution of happiness, although the ordinal nature of the data makes the use of standard inequality measures problematic. Our paper contributes to the literature by exploring the distributions for the U. S. from 1972 to 2010. Based on new methods developed for ordinal data, we are able to overcome the problems associated with ordinality and obtain unambiguous rankings of happiness distributions. We also compute the level of happiness inequality using existing measures based on median centred approaches. Further, we decompose the median based inequality measures of happiness by gender, race, and region. [ABSTRACT FROM AUTHOR]

Formic acid (FA) has been well recognized as one of the most promising hydrogen carriers. The dehydrogenation of the FA could offer an efficient process to on-demand hydrogen generation with a suitable catalyst. Homogeneous catalysts have demonstrated superior activity and selectivity compared to traditional heterogeneous catalysis. However, the latter is preferred for large-scale applications. By incorporating the homogeneous organometallic complex onto an appropriate support, the unique features of both types of catalysts can be combined and utilized effectively. Herein, we synthesized an immobilized PN3P-Ir pincer catalyst (2) supported onto KCC-1, a 3D fibrous silica nanosphere that exhibits a high surface area and contains a tetracoordinate aluminum site. To reduce the use of volatile additives, the choice of cesium formate (CsO 2 CH) was found to be crucial as at 80–90 °C, CsO 2 CH could act as a reaction medium and serve as basic additive. Remarkable reactivities under neat conditions were achieved with a TOF of 13,290 h-1 and a TON of up to 540,000. The comparative study indicates a significant improvement of 2 from its homogenous counterpart, PN3P-IrH 3 (1). Neat Formic Acid Dehydrogenation: The synthesized immobilized PN3P pincer iridium catalyst (2) showed remarkable reactivity under neat conditions to achieve a TOF of 13,290 h-1 and TON up to 540,000 compared to a homogenous PN3P pincer iridium catalyst (1). Cesium formate (CsO 2 CH) was found to act as a molten matrix and serve as both solvent and basic additive in the formic acid dehydrogenation. The overall study revealed that 2 shows superior activity, selectivity, and stability for the neat formic acid dehydrogenation. [Display omitted] • CsO 2 CH acts as both solvent and basic additive. • The larger negative charge on immobilized PN3P-Ir improves the formic acid dehydrogenation activity. [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]

• Copper Nitride Nanowires formation by a simple low cost Spray Pyrolysis Technique. • Revealed low absorption in UV range and enhanced absorption in visible and NIR ranges. • The direct and indirect optical band gaps were found to be 1.75 eV and 1.5 eV respectively. • The light dependent resistance of the fabricated nanowires was tested. • Indicate applicability in using as the light sensing devices. Semiconducting grade copper nitride(Cu 3 N) nanowires have been fabricated using a simple and low-cost method. The standard technique for fabricating Cu 3 N nanowires is physical methods and this is costly due to the involvement of capital equipment and recurring input. In the present method the Cu 3 N nanowires have been fabricated using chemical spray pyrolysis of thiourea and ammonium hydroxide over hot copper (Cu) foil substrate surface. The present process involves meager capital equipment and low recurring input. Studies on the quality of nanowires fabricated by the present method have been conducted using various molar concentration of spray solution and the ambient temperature of Cu substrates. The structural analysis indicated about the formation of cubic Cu 3 N. The optical analysis indicated about the low absorption in UV range and enhanced absorption in visible and NIR ranges with variation of direct and indirect bandgap of nanowire ranging from 1.5 to 1.79 eV. The light dependent resistance of the fabricated nanowires was tested and indicated its applicability in usage as light sensing devices. The result obtained so far is similar with that of Cu 3 N nanowires fabricated by physical deposition method. The present method for fabrication of Cu 3 N nanowires is simple and can be adopted by industries for large scale fabrication of nanowires for various device applications. Detailed fabrication technique and various properties of the nanowires are discussed in the text of the paper. [ABSTRACT FROM AUTHOR]