Dissipative Scaling Functions in Navier-Stokes Turbulence: Experimental Tests

A recent theoretical development in the understanding of the small-scale structure of Navier-Stokes turbulence has been the proposition that the scales $\eta_n(R)$ that separate inertial from viscous behavior of many-point correlation functions depend on the order $n$ and on the typical separations $R$ of points in the correlation. This is a proposal of fundamental significance in itself but it also has implications for the inertial range scaling behaviour of various correlation functions. This dependence has never been observed directly in laboratory experiments. In order to observe it, turbulence data which both display a well-developed scaling range with clean scaling behaviour and are well-resolved in the small scales to well within the viscous range is required. We have analysed the data of the experiments performed in the laboratory of P. Tabeling of Navier-Stokes turbulence in a helium cell with counter-rotating disks, and find that this data satisfies these criteria. We have been able to find strong evidence for the existence of the predicted scaling of the viscous scale.Comment: PRL, submitted, REVTeX, 4 pages, 4 figures, included. Online (HTML) and PS versions of this and related papers available at http://lvov.weizmann.ac.il/onlinelist.htm

A CASE STUDY OF THE RESPONSE OF NEWSROOM MANAGERS TO THE PSYCHOLOGICAL AFFECTS ON NEWSROOM EMPLOYEES OF THE COVERAGE OF A TRAUMATIC NEWS STORY

Journalists are exposed to traumatic situations every day. Some studies have been done on the lasting effects of the trauma caused by large scale events, such as 9/11 or Hurricane Katrina, but few studies have been conducted on the effects of everyday trauma, such as murder or any other violent crime. Therefore, little is done from a newsroom management standpoint to help address any psychological needs journalists may have following the coverage of a traumatic event. This study examines the Amish school shooting in Nickel Mines, Pennsylvania, on October 2, 2006 and the effect it had on employees in the WGAL-TV newsroom. In that shooting, five little girls were killed and another five were wounded. WGAL is the NBC affiliate for the market and is the only station in the market to be based in Lancaster County, where the shooting happened. Because of that, WGAL was first on the air with the story and was the first media outlet on the scene to begin coverage, arriving just moments after emergency personnel. WGAL is known in the broadcast news industry and in the community for its skilled ability to cover breaking news well. The coverage of the Amish school shooting was no different, except that it seemed to impact employees differently from the coverage of most stories. Newsroom employees participated in the study by responding to a questionnaire, describing their feelings during the coverage and following the coverage. They also were asked to discuss how they felt their emotional needs during the coverage and afterward were v addressed by managers in the newsroom. For the most part, employees felt managers were sensitive to the fact that employees might be struggling emotionally with the story. However, many made suggestions about how managers, both in the WGAL newsroom and in newsrooms around the country, could better address the emotional needs of newsroom employees during coverage of a traumatic event. This study focuses primarily on Acute Stress Disorder, as distinct from Posttraumatic Stress Disorder (a disorder which is usually associated with exposure to a long-term stressful situation such as a war, and the symptoms of which tend to develop over a relatively longer period of time than those of ASD), mainly because of the length of time employees indicated their feelings lasted. Again, very little study has been done on Acute Stress Disorder in journalists. Continued exposure to one traumatic story, or a series of traumatic stories can lead to Acute Stress Disorder and it’s important for newsroom managers to be able to recognize the warning signs and be able to help the employees address the problem

Summary of Workshop to Review an OMB Report on Regulatory Risk Assessment and Management

Summary of the results of an invitational workshop conducted to peer review the 1990 OMB report, CURRENT REGULATORY ISSUES IN Risk ASSESSMENT AND Risk MANAGENMENTIN REGULATORY PROGRAM OF THE UNITED STATES GOVERNMENT, APRIL 1, 1990 - MARCH 31, 1991

High-Resolution X-ray Spectroscopy of the Interstellar Medium: Structure at the Oxygen Absorption Edge

(Abbrev.) We present high-resolution spectroscopy of the oxygen K-shell interstellar absorption edge in 7 X-ray binaries using the HETGS onboard Chandra. Using the brightest sources as templates, we found a best-fit model of 2 absorption edges and 5 Gaussian absorption lines. All of these features can be explained by the recent predictions of K-shell absorption from neutral and ionized atomic oxygen. We identify the K alpha and K beta absorption lines from neutral oxygen, as well as the S=3/2 absorption edge. The expected S=1/2 edge is not detected in these data due to overlap with instrumental features. We also identify the K alpha absorption lines from singly and doubly ionized oxygen. The OI K alpha absorption line is used as a benchmark with which to adjust the absolute wavelength scale for theoretical predictions of the absorption cross-sections. We find that shifts of 30-50 mA are required, consistent with differences previously noticed from comparisons of the theory with laboratory measurements. Significant oxygen features from dust or molecular components, as suggested in previous studies, are not required by our HETGS spectra. With these spectra, we can begin to measure the large-scale properties of the ISM. We place a limit on the velocity dispersion of the neutral lines of <200 km s^{-1}, consistent with measurements at other wavelengths. We also make the first measurement of the oxygen ionization fractions in the ISM. We constrain the interstellar ratio of OII/OI to ~0.1 and the ratio of OIII/OI to <0.1.Comment: 12 pages, 8 figures, accepted for publication in the Astrophysical Journal (Vol. 612, September 1 issue

Genome-Wide Association to Body Mass Index and Waist Circumference: The Framingham Heart Study 100K Project

BACKGROUND: Obesity is related to multiple cardiovascular disease (CVD) risk factors as well as CVD and has a strong familial component. We tested for association between SNPs on the Affymetrix 100K SNP GeneChip and measures of adiposity in the Framingham Heart Study. METHODS: A total of 1341 Framingham Heart Study participants in 310 families genotyped with the Affymetrix 100K SNP GeneChip had adiposity traits measured over 30 years of follow up. Body mass index (BMI), waist circumference (WC), weight change, height, and radiographic measures of adiposity (subcutaneous adipose tissue, visceral adipose tissue, waist circumference, sagittal height) were measured at multiple examination cycles. Multivariable-adjusted residuals, adjusting for age, age-squared, sex, smoking, and menopausal status, were evaluated in association with the genotype data using additive Generalized Estimating Equations (GEE) and Family Based Association Test (FBAT) models. We prioritized mean BMI over offspring examinations (1–7) and cohort examinations (10, 16, 18, 20, 22, 24, 26) and mean WC over offspring examinations (4–7) for presentation. We evaluated associations with 70,987 SNPs on autosomes with minor allele frequencies of at least 0.10, Hardy-Weinberg equilibrium p ≥ 0.001, and call rates of at least 80%. RESULTS: The top SNPs to be associated with mean BMI and mean WC by GEE were rs110683 (p-value 1.22*10-7) and rs4471028 (p-values 1.96*10-7). Please see for the complete set of results. We were able to validate SNPs in known genes that have been related to BMI or other adiposity traits, including the ESR1 Xba1 SNP, PPARG, and ADIPOQ. CONCLUSION: Adiposity traits are associated with SNPs on the Affymetrix 100K SNP GeneChip. Replication of these initial findings is necessary. These data will serve as a resource for replication as more genes become identified with BMI and WC.National Heart, Lung, and Blood Institute's Framingham Heart Study (N01-HC-25195); Atwood (R01 DK066241); National Institutes of Health National Center for Research Resources Shared Instrumentation grant (1S10RR163736-01A1