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RuNPs stabilised by amino‐decorated imidazolium‐based polymer immobilized ionic liquids catalyse the dimethylamine borane mediated reduction of quinolines to 1,2‐dihydroquinoline (DHQ) and 1,2,3,4‐tetrahydroquinoline (THQ). Partial reduction of 3‐substituted quinolines to the corresponding 1,2‐dihydroquinoline was achieved with 100 % selectivity in toluene under mild conditions. This is the first report of the selective partial reduction of 3‐substituted quinolines to the corresponding 1,2‐dihydroquinolines with a heterogeneous nanoparticle‐based catalyst. A wide range of substituted quinolines have also been reduced to the corresponding 1,2,3,4‐tetrahydroquinoline with high selectivity and good yields by adjusting the reaction time. The 1,2‐dihydroquinolines readily release dihydrogen in toluene at 60 °C in the absence of catalyst with no evidence for disproportionation and as such are potential organo‐hydride reagents. The initial TOF of 610 mol quinoline converted mol Ru−1 h−1 for the reduction of quinoline is among the highest to be reported for a metal nanoparticle‐based catalyst and the conversion of 96 % obtained after 4 h at 65 °C is significantly higher than its platinum nanoparticle counterpart PtNP@NH2‐PEGPIILS as well as 5 wt/% Ru/C, which only reached 9 % and 11 % conversion, respectively, at the same time. Hot filtration experiments showed that the active species was heterogeneous. [ABSTRACT FROM AUTHOR]

Platinum nanoparticles stabilized by imidazolium‐based phosphine‐decorated Polymer Immobilized Ionic Liquids (PPh2‐PIIL) catalyze the hydrolytic evolution of hydrogen from sodium borohydride with remarkable efficiency, under mild conditions. The composition of the polymer influences efficiency with the catalyst based on a polyethylene glycol modified imidazolium monomer (PtNP@PPh2‐PEGPIILS) more active than its N‐alkylated counterpart (PtNP@PPh2‐N‐decylPIILS). The maximum initial TOF of 169 moleH2.molcat−1.min−1 obtained at 30 °C with a catalyst loading of 0.08 mol% is among the highest to be reported for the aqueous phase hydrolysis of sodium borohydride catalyzed by a PtNP‐based system. Kinetic studies revealed that the apparent activation energy (Ea) of 23.9 kJ mol−1 for the hydrolysis of NaBH4 catalyzed by PtNP@PPh2‐PEGPIILS is significantly lower than that of 35.6 kJ mol−1 for PtNP@PPh2‐N‐decylPIILS. Primary kinetic isotope effects kH/kD of 1.8 and 2.1 obtained with PtNP@PPh2‐PEGPIILS and PtNP@PPh2‐N‐decylPIILS, respectively, for the hydrolysis with D2O support a mechanism involving rate determining oxidative addition or σ‐bond metathesis of the O−H bond. Catalyst stability and reuse studies showed that PtNP@PPh2‐PEGPIILS retained 70 % of its activity across five runs; the gradual drop in conversion appears to be due to poisoning of the catalyst by the accumulated metaborate product as well as the increased viscosity of the reaction mixture. [ABSTRACT FROM AUTHOR]

Controlling the structure sensitivity of catalyzed reactions over metals is central to developing atom‐efficient chemical processes. Approaching the minimum ensemble size, the properties enter a non‐scalable regime in which each atom counts. Almost all trends in this ultra‐small frontier derive from surface science approaches using model systems, because of both synthetic and analytical challenges. Exploiting the unique coordination chemistry of carbon nitride, we discriminate through experiments and simulations the interplay between the geometry, electronic structure, and reactivity of palladium atoms, dimers, and trimers. Catalytic tests evidence application‐dependent requirements of the active ensemble. In the semi‐hydrogenation of alkynes, the nuclearity primarily impacts activity, whereas the selectivity and stability are affected in Suzuki coupling. This powerful approach will provide practical insights into the design of heterogeneous catalysts comprising well‐defined numbers of atoms. [ABSTRACT FROM AUTHOR]

When actions generate negative externalities for third parties, incentives exist to pass these “morally costly” decisions to others. In laboratory experiments, we investigate how market interaction affects allocations when the right to divide a sum of money between oneself and a passive recipient is commoditized. Allocation to recipients is reduced by more than half when determined by subjects who purchase or keep the right to make the division as compared to a control where subjects are directly assigned the right. Sellers report accurate beliefs about recipient allocations and do not report feeling less responsible the more often they sell the allocation right. The market allocates the right to make divisions more frequently to buyers who allocate more to recipients, but sellers who allocate less to recipients tend to sell less often. Selection cannot solely explain the results, suggesting market interaction itself may directly impact behavior. [ABSTRACT FROM AUTHOR]

Objective To evaluate the association of heart rate variability with job strain in first year resident physicians. Methods We performed the study at the 'Manuel Gea González' General Hospital in Mexico City. 54 resident doctors were studied over a period of 24 hr in their first year of specialization. Two questionnaires were administered: the first on general demographics, and the second, the Job Content Questionnaire. Heart rate variability was evaluated through the frequency domain (low-frequency power, high-frequency power, and low-frequency power/high-frequency power ratio) and time domain (SDNN). The doctors wore a Holter monitor over a 24-hr period, which included a workday plus their on-call time. They recorded their activities in a log. Results Compared to physicians in the 'low strain' category, physicians working in the 'passive' category had lower overall peak-to-peak cardiac variability (standard deviation of N-N intervals, SDNN), −9.08% (95% CI −17.97, 0.74), a −25% (95% CI −45.00, 0.22) lower high-frequency power, and −26.95% (95% CI −39.00, −12.53) lower low-frequency power. Physicians working in the 'high strain' category had lower low-frequency power, −17.85% (95%CI −32.34, −0.25), and lower low-frequency/high-frequency ratio −24.29% (95% CI 38.08, 7.42) compared to those in the 'low strain' category. Conclusions High job strain and low job control among medical residents were associated with several indicators of lowered heart rate variability. Thus, analysis of heart rate variability may be an informative marker for evaluating the physiological impacts of workplace stressors. Am. J. Ind. Med. 56:38-48, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background: Despite the epidemiological evidence linking job strain to cardiovascular disease, more insight is needed into the etiologic mechanisms. This, in turn, would help to more precisely identify risk., Methods: We measured Job Strain using the Job Content Questionnaire, 8/day diary reports, and nationally standardized occupational code linkage, as well as autonomic regulation utilizing heart rate variability including spectral-derived components and QT interval variability in 36 healthy mid-aged males with varying strain jobs. The subjects wore Holter-monitors for 48 hr; this included a work and rest day., Results: Job strain (P = 0.02) and low decision latitude (P = 0.004) were associated with a reduction in cardiac vagal control (HFP) persisting throughout the 48 hr. Job strain was also associated with elevations in sympathetic control during working hours (P = 0.003)., Conclusions: The disturbed cardiovascular regulatory pattern associated with job strain may help explain the increased risk of cardiovascular diseases linked with occupational exposure.