Oxygen reduction reaction (ORR), O2 + 4(H+ + e–) → 2H2O, is one of the most important fundamental reactions occurring on the cathode catalytic surface of hydrogen fuel cells. Developing new catalysts by alloying metals other than the well-known but expensive Pt is the most feasible and economical way to improve the proficiency of fuel cells to a practicable level. In this paper, we employed density functional theory calculations to study the ORR mechanism on a promising and cheaper catalyst of PdCo(111) surface alloy. From the calculated enthalpy of mixing, we found that the alloy is most stable at about 30% Co; hence, the alloying substrates were sampled at this concentration of Co for exploring the ORR intermediates. We discovered on the PdCo substrates a new intermediate OHO that was not seen previously for Pt and Pd resulting in a new reaction pathway. From the detailed analysis on the reaction free energy diagrams, we gauged the ORR efficiency of the alloy versus Pt. The obtained results are in agreement with experiments in which the ORR activity of the alloy was found to be higher than that of Pt. We found that maximizing the number of Co atoms at the second atomic layer underneath a Pd skin provides the highest activity for the ORR.

Background: Dispatch services (DS's) form an integral part of emergency medical service (EMS) systems. The role of a dispatcher has also evolved into a crucial link in patient care delivery, particularly in dispatcher assisted cardiopulmonary resuscitation (DACPR) during out-of-hospital cardiac arrest (OHCA). Yet, there has been a paucity of research into the emerging area of dispatch science in Asia. This paper compares the characteristics of DS's, and state of implementation of DACPR within the Pan-Asian Resuscitation Outcomes (PAROS) network. Methods: A cross-sectional descriptive survey addressing population characteristics, DS structures and levels of service, state of DACPR implementation (including protocols and quality improvement programs) among PAROS DS's. Results: 9 DS's responded, representing a total of 23 dispatch centres from 9 countries that serve over 80 million people. Most PAROS DS's operate a tiered dispatch response, have implemented medical oversight, and tend to be staffed by dispatchers with a predominantly medical background. Almost all PAROS DS's have begun tracking key EMS indicators. 77.8% (n = 7) of PAROS DS's have introduced DACPR. Of the DS's that have rolled out DACPR, 71.4% (n = 5) provided instructions in over one language. All DS's that implemented DACPR and provided feedback to dispatchers offered feedback on missed OHCA recognition. The majority of DS's (83.3%; n = 5) that offered DACPR and provided feedback to dispatchers also implemented corrective feedback, while 66.7% (n = 4) offered positive feedback. Compression-only CPR was the standard instruction for PAROS DS's. OHCA recognition sensitivity varied widely in PAROS DS's, ranging from 32.6% (95% CI: 29.9-35.5%) to 79.2% (95% CI: 72.9-84.4%). Median time to first compression ranged from 120 s to 220 s. Conclusions: We found notable variations in characteristics and state of DACPR implementation between PAROS DS's. These findings will lay the groundwork for future DS and DACPR studies in the PAROS network.

Rationale: Directly comparative data on sepsis epidemiology and sepsis bundle implementation in countries of differing national wealth remain sparse.Objectives: To evaluate across countries/regions of differing income status in Asia 1) the prevalence, causes, and outcomes of sepsis as a reason for ICU admission and 2) sepsis bundle (antibiotic administration, blood culture, and lactate measurement) compliance and its association with hospital mortality.Methods: A prospective point prevalence study was conducted among 386 adult ICUs from 22 Asian countries/regions. Adult ICU participants admitted for sepsis on four separate days (representing the seasons of 2019) were recruited.Measurements and Main Results: The overall prevalence of sepsis in ICUs was 22.4% (20.9%, 24.5%, and 21.3% in lowincome countries/regions [LICs]/lower middle-income countries/ regions [LMICs], upper middle-income countries/regions, and high-income countries/regions [HICs], respectively; P , 0.001).Patients were younger and had lower severity of illness in LICs/ LMICs. Hospital mortality was 32.6% and marginally significantly higher in LICs/LMICs than HICs on multivariable generalized mixed model analysis (adjusted odds ratio, 1.84; 95% confidence interval, 1.00-3.37; P = 0.049). Sepsis bundle compliance was 21.5% at 1 hour (26.0%, 22.1%, and 16.2% in LICs/LMICs, upper middle-income countries/regions, and HICs, respectively; P , 0.001) and 36.6% at 3 hours (39.3%, 32.8%, and 38.5%, respectively; P = 0.001). Delaying antibiotic administration beyond 3 hours was the only element independently associated with increased mortality (adjusted odds ratio, 2.53; 95% confidence interval, 2.07-3.08; P , 0.001).Conclusions: Sepsis is a common cause of admission to Asian ICUs. Mortality remains high and is higher in LICs/LMICs after controlling for confounders. Sepsis bundle compliance remains low. Delaying antibiotic administration beyond 3 hours from diagnosis is associated with increased mortality.Clinical trial registered with www.ctri.nic.in (CTRI/2019/01/016898).

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Improving the slow kinetics of oxygen reduction reaction (ORR) on the cathode of the proton exchange membrane fuel cells to achieve the performance at a practical level is an important task. PdCo alloys appeared as a promising electrocatalyst. Much attention has been devoted to the study of the effects of the Co content on the ORR activity of PdCo films and PdCo/C nanoparticles where the Co atoms can be at the topmost surface layer. While Pdskin/PdCo alloys with the topmost layer formed only by Pd have been proved to provide a very high ORR activity and high durability, no researches are available in the literature for the effects of the Co content on the ORR activity of Pd-skin/PdCo alloys. Hence, the effects of the Co content on the ORR activity of Pd-skin/PdCo alloys are clarified in this work by using the density functional theory calculations and Norskov's thermodynamic model. Our results predicted that the ORR activity increases monotonically with the increase of the Co content. This behavior is particularly different compared to the Volcano behavior previously obtained in the literature for PdCo films and PdCo/C nanoparticles.

We have studied the dissociation process of nitric oxide (NO) on Cu(110) and the influence of the hydrogen bond with water by means of density functional theory calculations. We have found that an upright NO adsorbed at a short-bridge site and a side-on NO at a hollow site connecting two short-bridge sites are the two most stable molecularly adsorbed states, and the latter is the precursor for the dissociation process. Various NO dissociation pathways under the influences of the hydrogen bonds with water have been investigated. We have found that hydrogen bonds efficiently reduce the activation energy of NO dissociation by the introductions of a water dimer to O and water dimers to both sides of the side-on NO, respectively. More importantly, the promoting effect of water molecules on NO dissociation is dominant only when one of water molecules in a water dimer forms a hydrogen bond with O of the side-on NO. Our results provide a physical insight into the promoting effect of hydrogen bonds with water, which may be helpful in improving the catalytic activity as well as designing novel catalysts for NO reduction.

We have studied the adsorption of small nitric oxide (NO) clusters [(NO) n (n = 1−3)] on Cu(111), by means of the van der Waals density functional. We have found that a single NO molecule preferably adsorbs in an upright N-down configuration at the fcc-hollow site, whereas all constituent NO molecules of the NO dimer and trimer adsorb at the fcc-hollow sites, in inclined Ndown geometries. Among three NO clusters, the NO trimer is the most stable regardless of lateral periodicities, in good agreement with the scanning tunneling microscopy experiment. van der Waals interaction dominates the stabilization of the NO dimer, while the hybridization among 2π* orbitals of NO plays an important role in addition to the van der Waals interaction in the formation of the NO trimer. The relatively weak interaction between the NO and Cu substrate is crucial for the stabilization of the NO trimer. Our vibrational analysis has revealed that the N−O stretching mode is blue-shifted from monomer to trimer, and the latter agrees well with the electron energy loss spectroscopy data.

Pressure modifies both electronic and optical properties; however, PEI adsorption only alters the electronic structure of monolayer MoS2.