Origins of the Ambient Solar Wind: Implications for Space Weather

The Sun's outer atmosphere is heated to temperatures of millions of degrees, and solar plasma flows out into interplanetary space at supersonic speeds. This paper reviews our current understanding of these interrelated problems: coronal heating and the acceleration of the ambient solar wind. We also discuss where the community stands in its ability to forecast how variations in the solar wind (i.e., fast and slow wind streams) impact the Earth. Although the last few decades have seen significant progress in observations and modeling, we still do not have a complete understanding of the relevant physical processes, nor do we have a quantitatively precise census of which coronal structures contribute to specific types of solar wind. Fast streams are known to be connected to the central regions of large coronal holes. Slow streams, however, appear to come from a wide range of sources, including streamers, pseudostreamers, coronal loops, active regions, and coronal hole boundaries. Complicating our understanding even more is the fact that processes such as turbulence, stream-stream interactions, and Coulomb collisions can make it difficult to unambiguously map a parcel measured at 1 AU back down to its coronal source. We also review recent progress -- in theoretical modeling, observational data analysis, and forecasting techniques that sit at the interface between data and theory -- that gives us hope that the above problems are indeed solvable.Comment: Accepted for publication in Space Science Reviews. Special issue connected with a 2016 ISSI workshop on "The Scientific Foundations of Space Weather." 44 pages, 9 figure

A phase 2, double-blind, multicenter, randomized, placebo-controlled, dose‑ranging study of the efficacy and safety of Astodrimer Gel for the treatment of bacterial vaginosis

Background Astodrimer Gel contains a novel dendrimer intended to treat and prevent bacterial vaginosis. We assessed the efficacy and safety of Astodrimer Gel for treatment of bacterial vaginosis. Methods 132 women with bacterial vaginosis were randomized 1:1:1:1 to Astodrimer 0.5% (N = 34), 1% (N = 33), or 3% (N = 32) Gel or hydroxyethyl cellulose placebo gel (N = 33) at a dose of 5 g vaginally once daily for 7 days at 6 centers in the United States. The primary endpoint was clinical cure (no bacterial vaginosis vaginal discharge and no more than one of 1) vaginal pH ≥4.5; 2) ≥20% clue cells; or 3) positive whiff test) at study days 21–30. Secondary analyses included clinical cure at study days 9–12, patient-reported symptoms, acceptability and adverse events. Results The Astodrimer 1% Gel dose was superior to placebo for the primary and selected secondary efficacy measures in the modified intent-to-treat population. Clinical cure rates at day 9–12 were superior to placebo for the Astodrimer 3%, 1% and 0.5% Gel groups (62.5% [15/24; P = .002], 74.1% [20/27; P < .001], and 55.2% [16/29; P = .001], respectively, vs. 22.2% [6/27]). At day 21–30, clinical cure rates were 46.2% (12/26) for the 1% dose vs. 11.5% for placebo (3/26; P = .006). A greater proportion of patients reported absence of vaginal discharge and vaginal odor at day 9–12 and day 21–30 for Astodrimer Gel groups compared with placebo. Adverse events considered potentially treatment-related occurred in only 25% of Astodrimer Gel-treated patients vs. 22% of placebo patients. Conclusion Astodrimer Gel once daily for 7 days was superior to placebo for treatment of bacterial vaginosis and was well-tolerated. The 1% dose consistently showed the strongest efficacy across endpoints. These results support a role for Astodrimer Gel, 1%, as an effective treatment for bacterial vaginosis

Aberrant cryptic responsiveness of the pCAT®3- and pGL3-promoter reporter vectors

Transfection analyses are an informative method to assess the activity of specific promoter or enhancer elements in mammalian cells. Commercially available reporter vectors can be extremely useful investigative tools for such studies. This study reports that the pCAT®3- and pGL3-promoter vectors display cryptic responsiveness to androgens when they contain a DNA insert, while the empty vector, a commonly used negative control, is nonresponsive. Our studies initially aimed to characterize novel androgen-responsive DNA sequences in human genomic DNA through transactivational analyses. An isolated DNA fragment, designated ARC-3, contained three putative androgen response element “half-sites” and was androgen-responsive when cloned into the pCAT3-promoter vector. While we originally believed this to be a novel enhancer element, subsequent analyses of this clone revealed that this vector displays cryptic activity in the presence of an androgen. This was confirmed by cloning several unrelated DNA fragments that did not contain any known classic response elements into the pCAT3-promoter vector, all of which were found to be responsive. The empty vector (negative control) was again nonresponsive. The ARC-3 DNA fragment was also weakly responsive to stimulation when cloned into the pGL3-promotor vector, which is identical to the pCAT3-promoter vector, with the exception of an intron located 5′ of the chloramphenicol acetyltransferase gene, and the reporter genes. This work demonstrates that both the pCAT3- and pGL3-promoter vectors are inappropriate to assess androgen-responsive enhancers and emphasizes the importance of the careful selection of reporter vectors and controls when conducting transactivational analysis