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Influence of southern hemispheric biomass burning on midtropospheric distributions of nonmethane hydrocarbons and selected halocarbons over the remote South Pacific
Aircraft measurements of nonmethane hydrocarbons (NMHCs) and halocarbons were made over the remote South Pacific Ocean during late August-early October 1996 for NASA's Global Tropospheric Experiment (GTE) Pacific Exploratory Mission-Tropics A (PEM-Tropics A). This paper discusses the large-scale spatial distributions of selected trace gases encountered during PEM-Tropics A. The PEM-Tropics A observations are compared to measurements made over the southwestern pacific in early November 1995 as part of Aerosol Characterization Experiment (ACE 1). Continental pollution in the form of layers containing elevated levels of O3 was observed during a majority of PEM-Tropics flights, as well as during several ACE 1 flights. The chemical composition of these air masses indicates that they were not fresh and were derived from nonurban combustion sources. The substantial impact of biomass burning on the vertical structure of the South Pacific troposphere is discussed. Copyright 1999 by the American Geophysical Union
Planning and implementation of a FIGO postpartum intrauterine device initiative in six countries.
OBJECTIVE: To describe the process of planning and implementing a program of counselling and delivery of postpartum intrauterine devices (PPIUD) in 48 hospitals across six countries in Africa and Asia. METHODS: The process of planning the FIGO PPIUD initiative, selection of countries and hospitals, model of implementation, and lessons for the future are described. RESULTS: Country-level and hospital-based leadership were essential and training-the-trainer models were successful. There was a need for consistency of competency standards allowing for national variations. As the project progressed, additional steps were necessary for steady implementation of the initiative, specifically: establishment of a project steering committee and a data safety monitoring committee, audits of structure and process, and regular feedback of each center's performance to stimulate maintenance and enhancement of activities. Postnatal follow-up was challenging in many countries with fragmented maternity systems. CONCLUSION: The importance of professional leadership and commitment backed by robust data for monitoring and feedback are essential for success
Formation of Super-Earths
Super-Earths are the most abundant planets known to date and are
characterized by having sizes between that of Earth and Neptune, typical
orbital periods of less than 100 days and gaseous envelopes that are often
massive enough to significantly contribute to the planet's overall radius.
Furthermore, super-Earths regularly appear in tightly-packed multiple-planet
systems, but resonant configurations in such systems are rare. This chapters
summarizes current super-Earth formation theories. It starts from the formation
of rocky cores and subsequent accretion of gaseous envelopes. We follow the
thermal evolution of newly formed super-Earths and discuss their atmospheric
mass loss due to disk dispersal, photoevaporation, core-cooling and collisions.
We conclude with a comparison of observations and theoretical predictions,
highlighting that even super-Earths that appear as barren rocky cores today
likely formed with primordial hydrogen and helium envelopes and discuss some
paths forward for the future.Comment: Invited review accepted for publication in the 'Handbook of
Exoplanets,' Planet Formation section, Springer Reference Works, Juan Antonio
Belmonte and Hans Deeg, Ed
Security analysis of mobile edge computing in virtualized small cell networks
Based upon the context of Mobile Edge Computing (MEC) actual research and within the innovative scope of the SESAME EU-funded research project, we propose and assess a framework for security analysis applied in virtualised Small Cell Networks, with the aim of further extending MEC in the broader 5G environment. More specifically, by applying the fundamental concepts of the SESAME original architecture that aims at providing enhanced multi-tenant MEC services through Small Cells coordination and virtualization, we focus on a realistic 5G-oriented scenario enabling the provision of large multi-tenant enterprise services by using MEC. Then we evaluate several security issues by using a formal methodology, known as the Secure Tropos
Long-lived charged Higgs at LHC as a probe of scalar Dark Matter
We study inert charged Higgs boson production and decays at LHC
experiments in the context of constrained scalar dark matter model (CSDMM). In
the CSDMM the inert doublet and singlet scalar's mass spectrum is predicted
from the GUT scale initial conditions via RGE evolution. We compute the cross
sections of processes at the LHC and show that
for light the first one is dominated by top quark mediated 1-loop
diagram with Higgs boson in s-channel. In a significant fraction of the
parameter space are long-lived because their decays to predominantly
singlet scalar dark matter (DM) and next-to-lightest (NL) scalar, are suppressed by the small singlet-doublet mixing
angle and by the moderate mass difference
The experimentally measurable displaced vertex in decays to leptons
and/or jets and missing energy allows one to discover the signal over
the huge background. We propose benchmark points for studies of this
scenario at the LHC. If, however, are short-lived, the subsequent
decays necessarily produce additional
displaced vertices that allow to reconstruct the full decay chain.Comment: 15 pages, 5 figure
Gac two-component system in Pseudomonas syringae pv. tabaci is required for virulence but not for hypersensitive reaction
Pseudomonas syringae pv. tabaci 6605 causes wildfire disease on host tobacco plants. To investigate the regulatory mechanism of the expression of virulence, Gac two-Component system-defective mutants, Delta gacA and Delta gacS, and a double mutant, Delta gacA Delta gacS, were generated. These mutants produced smaller amounts of N-acyl homoserine lactones required for quorum sensing, had lost swarming motility, and had reduced expression of virulence-related hrp genes and the algT gene required for exopolysaccharide production. The ability of the mutants to cause disease symptoms in their host tobacco plant was remarkably reduced, while they retained the ability to induce hypersensitive reaction (HR) in the nonhost plants. These results indicated that the Gac two-component system of P. syringae pv. tabaci 6605 is indispensable for virulence on the host plant, but not for HR induction in the nonhost plants.</p
Response of the mouse lung transcriptome to welding fume: effects of stainless and mild steel fumes on lung gene expression in A/J and C57BL/6J mice
<p>Abstract</p> <p>Background</p> <p>Debate exists as to whether welding fume is carcinogenic, but epidemiological evidence suggests that welders are an at risk population for the development of lung cancer. Recently, we found that exposure to welding fume caused an acutely greater and prolonged lung inflammatory response in lung tumor susceptible A/J versus resistant C57BL/6J (B6) mice and a trend for increased tumor incidence after stainless steel (SS) fume exposure. Here, our objective was to examine potential strain-dependent differences in the regulation and resolution of the lung inflammatory response induced by carcinogenic (Cr and Ni abundant) or non-carcinogenic (iron abundant) metal-containing welding fumes at the transcriptome level.</p> <p>Methods</p> <p>Mice were exposed four times by pharyngeal aspiration to 5 mg/kg iron abundant gas metal arc-mild steel (GMA-MS), Cr and Ni abundant GMA-SS fume or vehicle and were euthanized 4 and 16 weeks after the last exposure. Whole lung microarray using Illumina Mouse Ref-8 expression beadchips was done.</p> <p>Results</p> <p>Overall, we found that tumor susceptibility was associated with a more marked transcriptional response to both GMA-MS and -SS welding fumes. Also, Ingenuity Pathway Analysis revealed that gene regulation and expression in the top molecular networks differed between the strains at both time points post-exposure. Interestingly, a common finding between the strains was that GMA-MS fume exposure altered behavioral gene networks. In contrast, GMA-SS fume exposure chronically upregulated chemotactic and immunomodulatory genes such as <it>CCL3</it>, <it>CCL4</it>, <it>CXCL2</it>, and <it>MMP12 </it>in the A/J strain. In the GMA-SS-exposed B6 mouse, genes that initially downregulated cellular movement, hematological system development/function and immune response were involved at both time points post-exposure. However, at 16 weeks, a transcriptional switch to an upregulation for neutrophil chemotactic genes was found and included genes such as <it>S100A8</it>, <it>S100A9 </it>and <it>MMP9</it>.</p> <p>Conclusions</p> <p>Collectively, our results demonstrate that lung tumor susceptibility may predispose the A/J strain to a prolonged dysregulation of immunomodulatory genes, thereby delaying the recovery from welding fume-induced lung inflammation. Additionally, our results provide unique insight into strain- and welding fume-dependent genetic factors involved in the lung response to welding fume.</p
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