A new chemistry-climate tropospheric and stratospheric model MOCAGE-Climat: evaluation of the present-day climatology and sensitivity to surface processes

International audienceWe present the chemistry-climate configuration of the Météo-France Chemistry and Transport Model, MOCAGE-Climat. MOCAGE-Climat is a state-of-the-art model that simulates the global distribution of ozone and its precursors (82 chemical species) both in the troposphere and the stratosphere, up to the mid-mesosphere (~70 km). Surface processes (emissions, dry deposition), convection, and scavenging are explicitly described in the model that has been driven by the ECMWF operational analyses of the period 2000–2005, on T21 and T42 horizontal grids and 60 hybrid vertical levels, with and without a procedure that reduces calculations in the boundary layer, and with on-line or climatological deposition velocities. Model outputs have been compared to available observations, both from satellites (TOMS, HALOE, SMR, SCIAMACHY, MOPITT) and in-situ instrument measurements (ozone sondes, MOZAIC and aircraft campaigns) at climatological timescales. The distribution of long-lived species is in fair agreement with observations in the stratosphere putting apart shortcomings linked to the large-scale circulation. The variability of the ozone column, both spatially and temporarily, is satisfactory. However, the too fast Brewer-Dobson circulation accumulates too much ozone in the lower to mid-stratosphere at the end of winter. Ozone in the UTLS region does not show any systematic bias. In the troposphere better agreement with ozone sonde measurements is obtained at mid and high latitudes than in the tropics and differences with observations are the lowest in summer. Simulations using a simplified boundary layer lead to ozone differences between the model and the observations up to the mid-troposphere. NOx in the lowest troposphere is in general overestimated, especially in the winter months over the northern hemisphere, which might result from a positive bias in OH. Dry deposition fluxes of O3 and nitrogen species are within the range of values reported by recent inter-comparison model exercises. The use of climatological deposition velocities versus deposition velocities calculated on-line had greatest impact on HNO3 and NO2 in the troposphere

The moderation effect of personal factors on the relationship between performance contracting and service delivery of employees in Huduma Centres in Western Kenya

The Kenyan Government mounted the following efforts to improve service delivery: privatization, voluntary early retirement, and restructuring, but the results were not good, thereby opting for performance contracting using Huduma Centers. The 30,000 customers are served at the centres daily and collected Kshs 12 billion annually as revenue, as shown in a report by Government 2020. Past studies on performance contracting influencug service delivery were mostly case studies and not surveys. There were mixed outcomes from the reviewed literature, a sign of a moderator impact yet to be tested, and there were no evidence for examining personal characteristics to demonstrate their moderation effect. The impact of personal factors on the relationship between performance contracting and service delivery, on the other hand, has not been sufficiently explored. This study aimed to establish the moderation effect of personal factors on the relationship between performance contracting and service delivery. The study utilized an ex-post factor design with quantitative aspects. A questionnaire was used to gather data from a target population of 276. The data analysis was done quantitatively to establish the moderation effect. The results showed that personal factors (R2=0.125; p=0.000) positively and significantly influenced the association by 12.5 %. The study revealed that personal characteristics positively modified the association. The study recommends that managers and policymakers consider personal factors to enhance service delivery. The implication of this study for theory is that it would result in theory refinement by emphasizing the integration of personal factors in the performance contracting framework while opening research fronts for the future by recommending cross-sectoral studies that are qualitative to be carried out to gain insights into the variations of moderations of personal factors

The genetics of diabetes: What we can learn from Drosophila

Diabetes mellitus is a heterogeneous disease characterized by hyperglycemia due to impaired insulin secretion and/or action. All diabetes types have a strong genetic component. The most frequent forms, type 1 diabetes (T1D), type 2 diabetes (T2D) and gestational diabetes mellitus (GDM), are multifactorial syndromes associated with several genes’ effects together with environmental factors. Conversely, rare forms, neonatal diabetes mellitus (NDM) and maturity onset diabetes of the young (MODY), are caused by mutations in single genes. Large scale genome screenings led to the identification of hundreds of putative causative genes for multigenic diabetes, but all the loci identified so far explain only a small proportion of heritability. Nevertheless, several recent studies allowed not only the identification of some genes as causative, but also as putative targets of new drugs. Although monogenic forms of diabetes are the most suited to perform a precision approach and allow an accurate diagnosis, at least 80% of all monogenic cases remain still undiag-nosed. The knowledge acquired so far addresses the future work towards a study more focused on the identification of diabetes causal variants; this aim will be reached only by combining expertise from different areas. In this perspective, model organism research is crucial. This review traces an overview of the genetics of diabetes and mainly focuses on Drosophila as a model system, describing how flies can contribute to diabetes knowledge advancement

Interatomic and Intermolecular Coulombic Decay

Interatomic or intermolecular Coulombic decay (ICD) is a nonlocal electronic decay mechanism occurring in weakly bound matter. In an ICD process, energy released by electronic relaxation of an excited atom or molecule leads to ionization of a neighboring one via Coulombic electron interactions. ICD has been predicted theoretically in the mid nineties of the last century, and its existence has been confirmed experimentally approximately ten years later. Since then, a number of fundamental and applied aspects have been studied in this quickly growing field of research. This review provides an introduction to ICD and draws the connection to related energy transfer and ionization processes. The theoretical approaches for the description of ICD as well as the experimental techniques developed and employed for its investigation are described. The existing body of literature on experimental and theoretical studies of ICD processes in different atomic and molecular systems is reviewed. © 2020 American Chemical Societ

Who is a Student: Completion in Coursera Courses at Duke University

Much of the interest in MOOCs centers on questions about who completes them. Duke’s Coursera-based Massive Open Online Courses (MOOCs) confirm many demographic trends previously delineated by researchers at peer institutions. As found in previous research, this study found individuals who speak English as a first language and who already earned at least a bachelor’s degree are the most likely to complete a Coursera course. MOOC researchers to date have not, however, developed clear operational definitions about who constitutes a learner at the outset of the course. This paper proposes some possible definitions to standardize future research. Further, this study looked at factors that predict different learner participation levels and investigated which activities predict Coursera course completion. Study results indicated that viewing online forums and participation in online discussions are both predictive of course completion. The findings suggest that the socio-demographic composition of the group being investigated will depend on how researchers elect to define what a student is. Thus, while any of the definitions presented in this paper may be appropriate, depending on what is being studied, the decision of which definition to use should be intentional