bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microkinetic modeling in homogeneous catalysis
Authors: Besora Maria , Maseras Feliu 
Published: June 2018

Computational homogeneous catalysis has focused traditionally on the calculation of free energy barriers, which are ultimately related to rate constants. Experiments do not focus on rate constants, but on reaction rates, which depend also on concentrations. The increasing efficiency of DFT and other electronic structure techniques has led to the development of models that provide quite accurate rate constants, to the extent that improved agreement with experiment requires the introduction of the role of concentration. Microkinetic modeling, consisting in the construction of explicit kinetic reaction networks merging the rate constants provided by calculation and concentration data supplied by experiment, is a simple and elegant way to introduce concentration effects in the computational description of homogeneous catalysis. It has a long history of application in computational heterogeneous catalysis and experimental biochemistry, but its use in computational homogeneous catalysis is still in an early stage. There are a number of situations in homogeneous catalysis where microkinetics have been shown to be critical, such as systems with complex reaction networks and systems where one key species has a concentration orders of magnitude different from the others. Microkinetic modeling, with its low computational cost, is likely to become a standard tool in computational homogeneous catalysis. It is certainly not necessary for all theoretical studies, but the researcher should always be aware of its existence.This article is categorized under:

Structure and Mechanism > Reaction Mechanisms and Catalysis
Overexpressed maltose transporters in laboratory and lager yeasts: Localization and competition with endogenous transporters
Authors: Vidgren Virve , Londesborough John 
Published: June 2018

AbstractPlain and fluorescently tagged versions of Agt1, Mtt1 and Malx1 maltose transporters were overexpressed in two laboratory yeasts and one lager yeast. The plain and tagged versions of each transporter supported similar transport activities, indicating that they are similarly trafficked and have similar catalytic activities. When they were expressed under the control of the strong constitutive PGK1 promoter only minor proportions of the fluorescent transporters were associated with the plasma membrane, the rest being found in intracellular structures. Transport activity of each tagged transporter in each host was roughly proportional to the plasma membrane‐associated fluorescence. All three transporters were subject to glucose‐triggered inactivation when the medium glucose concentration was abruptly raised. Results also suggest competition between endogenous and overexpressed transporters for access to the plasma membrane.
On a generalized Camassa‐Holm type equation with ()‐degree nonlinearities
Authors: Guo Zhengguang , Li Kunquan , Xu Chongbin 
Published: June 2018

AbstractA detailed asymptotic description for solutions to a generalized Camassa‐Holm type equation with non‐positive compactly supported initial momentum is shown. Moreover, as a by product, we give an estimate of the momentum support which will reveal more information of solutions by estimating the size of this region where solutions are not that well understood.
Out‐of‐Pocket and Catastrophic Expenses Incurred by Seeking Pediatric and Adult Surgical Care at a Public, Tertiary Care Centre in Uganda
Authors: MacKinnon Nathalie , St‐Louis Etienne , Yousef Yasmine , Situma Martin , Poenaru Dan 
Published: June 2018

AbstractBackgroundSurgical care is critical to establish effective healthcare systems in low‐ and middle‐income countries, yet the unmet need for surgical conditions is as high as 65% in Ugandan children. Financial burden and geographical distance are common barriers to help‐seeking in adult populations and are unmeasured in the pediatric population. We thus measured out‐of‐pocket (OOP) expenses and distance traveled for pediatric surgical care in a tertiary hospital in Mbarara, Uganda, as compared to adult surgical and pediatric medical patients.MethodsPatients admitted to pediatric surgical (n = 20), pediatric medical (n = 18) and adult surgical (n = 18) wards were interviewed upon discharge over a period of 3 weeks. Patient and caregiver‐reported expenses incurred for the present illness included prior/future care needed, and travel distance/cost. The prevalence of catastrophic expenses (≥10% of annual income) was calculated and spending patterns compared between wards.ResultsThirty‐five percent of pediatric medical patients, 45% of pediatric surgical patients and 55% of adult surgical patients incurred catastrophic expenses. Pediatric surgical patients paid more for their current treatment (p <  0.01)—specifically medications (p <  0.01) and tests (p <  0.01)—than pediatric medical patients, and comparable costs to adults. Adult patients paid more for treatment prior to the hospital (p = 0.04) and miscellaneous expenses (e.g., food while admitted) (p = 0.02). Patients in all wards traveled comparable distances.ConclusionsSeeking healthcare at a publicly funded hospital is financially catastrophic for almost half of patients. Out‐of‐stock supplies and broken equipment make surgical care particularly vulnerable to OOP expenses because analgesics, anaesthesia and preoperative imaging are prerequisites to care.
CHILEAN TRADE 1880-1930: A COMMENT ON THE SOURCES FOR THE AGE OF EXPORTS
Authors: Badia-Miró Marc , Díaz-Bahamonde José 
Published: June 2018

AbstractThis research note discussesthe accuracyof the main sources used to study the foreign sector during the export-led growth process in Chile. Chilean foreign trade statistics are available for the period under analysis (1850-1930) and offered a good overview of products exported and imported. Bilateral trade data are also available providing information of exports and imports by origin and destiny. Although more research is needed on trade prices, we conclude that Chilean statistics are reliable and provide a way for understanding the export-led growth in Chile and the trade performance of the Chilean partners.
LA BANCA DE EMISIÓN ANDALUZA EN PERSPECTIVA NACIONAL (1856-1914)
Authors: Tedde De Lorca Pedro 
Published: June 2018

ABSTRACTThis article attempts to establish a quantitative revision of issuing banks created in Andalusia in the middle of nineteenth century founded as a result of liberal banking laws in 1856, comparing with those of similar dimension in other Spanish provinces. Possible causes of their soon extinction are discussed, like the financial worldwide crisis in the 1860s, the monopoly issue granted to the Bank of Spain in 1874 and the specific circumstances of regional banking. The article tries also to evaluate the performance of Bank of Spain branches, since 1875 until 1914, in those Andalusian places where issue banks were independent before and in relation to the fluctuations of the regional economy in that period.
A continuity result on quadratic matings with respect to parameters of odd denominator rationals
Authors: MA LIANGANG 
Published: June 2018

AbstractIn this paper we prove a continuity result on matings of quadratic lamination maps sp depending on odd denominator rationals p ∈(0,1). One of the two mating components is fixed in the result. Note that our result has its implication on continuity of matings of quadratic hyperbolic polynomials fc(z)=z2 + c, c ∈ M the Mandelbrot set with respect to the usual parameters c. This is because every quadratic hyperbolic polynomial in M is contained in a bounded hyperbolic component. Its center is Thurston equivalent to some quadratic lamination map sp, and there are bounds on sizes of limbs of M and on sizes of limbs of the mating components on the quadratic parameter slice Perm′(0).
Managing Disaster-Related Health Risk: A Process for Prevention
Authors: Keim Mark 
Published: June 2018

AbstractIn 1994, the first World Conference on Natural Disaster Reduction held in Yokohama, Japan affirmed that “Disaster prevention, mitigation, and preparedness are better than disaster response in achieving the goals and objectives of the decade. Disaster response alone is not sufficient, as it yields only temporary results in a very high cost.” Since then, disaster risk reduction has become the mainstay for international development related to disasters.According to the National Research Council (Washington, DC USA), “Disaster research, which has focused historically on emergency response and recovery, is incomplete without the simultaneous study of the societal hazards and risks associated with disasters, which includes data on the vulnerability of people living in hazard prone areas.” Despite over 25 years of global policy development, the National Academies of Sciences, Engineering, and Medicine (Washington, DC USA) recently noted that, “while some disaster management and public health preparedness programming may be viewed as tangentially related, a multi-sectoral and inter-disciplinary national platform for coordination and policy guidance on involving disaster risk reduction in the United States does not exist.” Today, one of the world’s “seven targets in seven years” as agreed upon in the Sendai Framework for Disaster Risk Reduction is to substantially reduce global mortality by 2030. Significant reductions in health risk (including mortality) have historically required a comprehensive approach for disease management that includes both a preventive and a curative approach. Disaster risk management has arisen as a primary means for the world’s populations to address disaster losses, including those related to health. Prevention has been proven as an effective approach for managing health risk. This report describes the role of disease prevention in managing health risk due to disasters.KeimM. Managing disaster-related health risk: a process for prevention. Prehosp Disaster Med. 2018;33(3):326-334.
Improving the nutrition and screen time environment through self-assessment in family childcare homes in Nebraska
Authors: Dev Dipti A , Williams Natalie , Iruka Iheoma , Garcia Aileen S , Guo Yage , Patwardhan Irina , Cummings Katrina , Rida Zainab , Hulse Emily , Sedani Ami 
Published: June 2018

AbstractObjectiveTo determine if family childcare homes (FCCH) in Nebraska meet best practices for nutrition and screen time, and if focusing on nutrition and screen time policies and practices improves the FCCH environment.DesignA pre–post evaluation was conducted using the Go Nutrition and Physical Activity Self-Assessment for Childcare (Go NAP SACC).SettingFCCH in Nebraska, USA.SubjectsFCCH enrolled in the Child and Adult Care Food Program (CACFP; n 208) participated in a pre–post evaluation using Go NAP SACC.ResultsAt baseline, all FCCH met the minimum childcare standards for fifty-four of fifty-six practices in nutrition and screen time. After the intervention, FCCH demonstrated significant improvement in fourteen of the forty-four Child Nutrition items and eleven of the twelve Screen Time items. However, FCCH providers did not meet best practices at post-intervention. Lowest scores were found in serving meals family-style, promoting visible support for healthy eating, planned nutrition education and written policy on child nutrition. For screen time, lowest scores were reported on the availability of television, offering families education on screen time and having a written policy on screen time.ConclusionsFCCH in Nebraska were able to strengthen their policies and practices after utilizing Go NAP SACC. Continued professional development and participation in targeted interventions may assist programmes in sustaining improved practices and policies. Considering the varying standards and policies surrounding FCCH, future studies comparing the current findings with childcare centres and non-CACFP programmes are warranted.
Chemical Analysis of Materials Exposed to Venus Temperature and Surface Atmosphere
Authors: Lukco D. , Spry D. J. , Harvey R. P. , Costa G. C. C. , Okojie R. S. , Avishai A. , Nakley L. M. , Neudeck P. G. , Hunter G. W. 
Published: June 2018

AbstractPlanetary exploration in the harsh Venus surface environment faces a myriad of technical challenges related to material survivability, durability, and overall reliable systems operation. An understanding of material reactions in Venus relevant atmospheric conditions is core to enabling future successful Venus science missions. This work investigated various candidate materials used in fabricating electronics, sensors, and packaging after exposure to simulated Venus surface atmosphere. The NASA Glenn Extreme Environments Rig is capable of reproducing Venusian temperature, pressure, and atmospheric composition of the Venus surface consisting mostly of CO2and N2as well as traces of SO2, H2O, CO, OCS, HCl, HF, and H2S. The exposed materials were characterized using Auger electron spectroscopy, X‐ray photoelectron spectroscopy, energy dispersive spectroscopy, field emission‐scanning electron microscopy, X‐ray diffraction, and optical imaging. The reactivity of the sulfur gas constituents with several of the exposed materials were found to have adverse effects on the materials, particularly those composed of transition metals. Alloys, brazes, and cladded materials all exhibited extensive reactions. In contrast, compounds of SiC, SiO2, Al2O3, and elemental Au and Ir were found to be chemically inert. The fundamental experimental understanding of material interactions with the simulated Venusian environment gained in this study enables improved selection of materials and hardware designs that would increase the success margin of future long duration science mission on Venus.
Remote Forcing of Shelf Flows by Density Gradients and the Origin of the Annual Mean Flow on the Mid‐Atlantic Bight
Authors: Pringle James M. 
Published: June 2018

AbstractIn the annual mean, a southwestward along‐isobath flow exists in the Mid‐Atlantic Bight. It has been shown to be driven neither by local winds, which are too weak and in the wrong direction to explain the flow, nor by local density gradients, which are too weak to explain the flow. Prior work has established that the mean flow is part of a local alongshore momentum balance between bottom friction and along‐isobath pressure gradient; but that work does not explain the origin of the pressure gradient. A simple model of shelf flows driven by density anomalies elsewhere on the shelf is developed. This model is used to argue that the annual average flow is consistent with remote forcing by density gradients on the shelf along the southern edge of the Laurentian Channel and the Scotian Shelf. These density gradients are largely caused by freshwater input from the Saint Lawrence River, and their effect when integrated over the Laurentian Channel, Scotian Shelf, and Gulf of Maine shows only a weak seasonal signal.
Impact of Moisture Information From Advanced Himawari Imager Measurements on Heavy Precipitation Forecasts in a Regional NWP Model
Authors: Wang Pei , Li Jun , Lu Bing , Schmit Timothy J. , Lu Jiazhen , Lee Yong‐Keun , Li Jinlong , Liu Zhiquan 
Published: June 2018

AbstractInformation about moisture distribution and transportation in the preconvection environment is very important for nowcasting and forecasting severe weather events. The Advanced Himawari Imager (AHI) onboard the Japanese Himawari‐8/‐9 provides high temporal and spatial resolution moisture information useful for weather monitoring and forecasting. Algorithms have been developed for three‐layered precipitable water (LPW: surface to 0.9, 0.9–0.7, and 0.7–0.3 in sigma vertical coordinate) retrievals from AHI infrared band radiances using a Geostationary Operational Environmental Satellite‐R series algorithm working group algorithm. The LPW products from AHI have been validated with in situ measurements. An important application of the AHI LPW product is to improve local severe storm forecasts through assimilating high temporal and spatial resolution moisture information into regional‐ and storm‐scale numerical weather prediction (NWP) models. Assimilation techniques and approaches have been developed; the impact on precipitation forecasts for local severe storm over land from the assimilation of LPWs from AHI shows improvement on heavy precipitation forecasts over those from the assimilation of conventional data. Comparisons between AHI infrared band radiance assimilation and LPW assimilation show overall similar or comparable impact on precipitation forecast. The approaches for assimilating LPW can be applied to the assimilation of data from other advanced imagers such as the Advanced Baseline Imager onboard the U.S. next generation of Geostationary Operational Environmental Satellites‐R series, the Advanced Geosynchronous Radiation Imager onboard the Chinese FengYun‐4 series, and the Flexible Combined Imager onboard the upcoming European Meteosat Third Generation.
Aqueous Processes From Diverse Hydrous Minerals in the Vicinity of Amazonian‐Aged Lyot Crater
Authors: Pan Lu , Ehlmann Bethany L. 
Published: June 2018

AbstractAmazonian‐aged Lyot crater is the best‐preserved and deepest peak‐ring impact crater (diameter, D = 220 km) in the northern lowlands of Mars. Morphological features including scouring channels emanating from its ejecta and small channels within the crater have been examined previously to understand hydrological activity associated with the crater. In this study, we analyze images acquired by the Compact Reconnaissance Imaging Spectrometer for Mars on board the Mars Reconnaissance Orbiter to investigate the mineralogical record in Lyot and its surroundings, which are presently enriched in ground ice, to understand the associated aqueous processes, their relative timing, and a possible role for ground ice in hydrous mineral formation. We find diverse hydrous minerals, including Fe/Mg phyllosilicates, chlorite, illite/muscovite, and prehnite in Lyot crater walls, central peak, and ejecta, as well as in two craters to the west of Lyot. The exposure and distribution of the hydrous minerals suggest that they are related to the impact process, either exposed by the excavation of hydrothermally altered rocks or formed through syn‐depositional hydrothermal alteration immediately after impacts. The Lyot impact induced channel formation to the north, but no mineralogical evidence of aqueous alteration associated with the channels is observed. The sinuous channels within Lyot, diverted by bedrock units with hydrous mineral detections, did not cause mineralization but likely represent the last stage of water activity in Lyot crater. The separate episodes of water activity indicate flow of liquid water on Mars' surface during the Amazonian but limited to no aqueous alteration to generate hydrous minerals.
Statistical Study of the Energetic Proton Environment at Titan's Orbit From the Cassini Spacecraft
Authors: Regoli L. H. , Roussos E. , Dialynas K. , Luhmann J. G. , Sergis N. , Jia X. , Román D. , Azari A. , Krupp N. , Jones G. H. , Coates A. J. , Rae I. J. 
Published: June 2018

AbstractA statistical study of the energetic proton environment at Titan's orbit as captured by the MIMI/LEMMS and MIMI/CHEMS instruments is performed. The data analyzed cover all the dedicated flybys of Titan by Cassini as well as the orbit crossings that happen far from the moon. The energetic environment is found to be highly variable on timescales comparable to that of the duration of a flyby. Analysis of H+ ion fluxes reveals a weak asymmetry in Saturn local time with the highest fluxes occurring in the premidnight sector of the magnetosphere. A correlation between the energetic ion fluxes and the location of Cassini in the magnetosphere with respect to the center of the current sheet can be observed. Finally, an empirical model of proton spectra for energies above 20 keV is derived based on fits to Kappa distribution functions. This model can be used to better understand the interaction of Titan with the magnetosphere and the energy deposition by energetic particles below the main ionospheric peak.
Radium Isotopes Across the Arctic Ocean Show Time Scales of Water Mass Ventilation and Increasing Shelf Inputs
Authors: Rutgers van der Loeff Michiel , Kipp Lauren , Charette Matthew A. , Moore Willard S. , Black Erin , Stimac Ingrid , Charkin Alexander , Bauch Dorothea , Valk Ole , Karcher Michael , Krumpen Thomas , Casacuberta Núria , Smethie William , Rember Robert 
Published: June 2018

AbstractThe first full transarctic section of 228Ra in surface waters measured during GEOTRACES cruises PS94 and HLY1502 (2015) shows a consistent distribution with maximum activities in the transpolar drift. Activities in the central Arctic have increased from 2007 through 2011 to 2015. The increased 228Ra input is attributed to stronger wave action on shelves resulting from a longer ice‐free season. A concomitant decrease in the 228Th/228Ra ratio likely results from more rapid transit of surface waters depleted in 228Th by scavenging over the shelf. The 228Ra activities observed in intermediate waters (<1,500 m) in the Amundsen Basin are explained by ventilation with shelf water on a time scale of about 15–18 years, in good agreement with estimates based on SF6 and 129I/236U. The 228Th excess below the mixed layer up to 1,500 m depth can complement 234Th and 210Po as tracers of export production, after correction for the inherent excess resulting from the similarity of 228Ra and 228Th decay times. We show with a Th/Ra profile model that the 228Th/228Ra ratio below 1,500 m is inappropriate for this purpose because it is a delicate balance between horizontal supply of 228Ra and vertical flux of particulate 228Th. The accumulation of 226Ra in the deep Makarov Basin is not associated with an accumulation of Ba and can therefore be attributed to supply from decay of 230Th in the bottom sediment. We estimate a ventilation time of 480 years for the deep Makarov‐Canada Basin, in good agreement with previous estimates using other tracers.
Formation of Evolved Rocks at Gale Crater by Crystal Fractionation and Implications for Mars Crustal Composition
Authors: Udry Arya , Gazel Esteban , McSween Harry Y. 
Published: June 2018

AbstractThe recent discovery of some ancient evolved rocks in Gale crater by the Curiosity rover has prompted the hypothesis that continental crust formed in early Martian history. Here we present petrological modeling that attempts to explain this lithological diversity by magma fractionation. Using the thermodynamical software MELTS, we model fractional crystallization of different Martian starting compositions that might generate felsic igneous compositions like those analyzed at Gale crater using different variables, such as pressure, oxygen fugacities, and water content. We show that similar chemical and mineralogical compositions observed in Gale crater felsic rocks can readily be obtained through different degrees of fractional crystallization of basaltic compositions measured on the Martian surface. The results suggest that Gale crater rocks may not represent true liquids as they possibly accumulated and/or fractionated feldspars as well as other phases. In terms of major element compositions and mineralogy, we found that the Gale crater felsic compositions are more similar to fractionated magmas produced in Earth's intraplate volcanoes than to terrestrial felsic continental crust as represented by tonalite‐trondhjemite‐granodiorite suites. We conclude that the felsic rocks in Gale crater do not represent continental crust, as it is defined on Earth.