Stability of the Submillimeter Brightness of the Atmosphere Above Mauna Kea, Chajnantor and the South Pole

The summit of Mauna Kea in Hawaii, the area near Cerro Chajnantor in Chile, and the South Pole are sites of large millimeter or submillimeter wavelength telescopes. We have placed 860 GHz sky brightness monitors at all three sites and present a comparative study of the measured submillimeter brightness due to atmospheric thermal emission. We report the stability of that quantity at each site.Comment: 6 figure

The wintertime South Pole tropospheric water vapor column: Comparisons of radiosonde and recent terahertz radiometry, use of the saturated column as a proxy measurement, and inference of decadal trends

We use a fifty-year record of wintertime radiosonde observations at the South Pole to estimate the precipitable water vapor column (PWV) over the entire period. Humidity data from older radiosondes is of limited reliability; however, we think an estimation of PWV is possible using temperature data because the wintertime lower troposphere is very close to saturated. From temperature data we derived PWV_SAT which is the PWV if the troposphere was saturated over the entire column. Comparisons to recent radiosonde humidity data indicate that PWV ≃ 0.88PWV_SAT. Since 1998 a CMU/NRAO 860 GHz atmospheric radiometer has been operating at the South Pole producing zenith opacity data, τo. It is expected that τo ∝ PWV, and also τ_o ∝ PWV_SAT, since the lower atmospheric column is near to saturation. We compare trends in τo, PWV_SAT, and PWV. PWV and PWV_SAT showed little trend in the last fifty years, 1961 to 2010, except perhaps in the last two decades, when PWVSAT was below average, followed by an increasing trend to above average. This increasing trend in the last decade was also observed in τo, except for the final two years when it appears that something changed in the instrument response. PWV_SAT is a useful metric for estimating PWV in the earlier years of wintertime South Pole radiosonde, and it is generally useful for evaluating the wintertime performance of radiosonde humidity and atmospheric opacity instrumentation

A simple approach to estimating three-dimensional supercavitating flow fields

A simple method is formulated for predicting three-dimensional supercavitating flow behind cavitators subject to gravitational acceleration and motion of the cavitator. The method applies slenderbody theory in the context of matched asymptotic expansions to pose an inner problem for the cavity evolution downstream from the locus of cavity detachment. This inner problem is solved by means of a coupled set of equations for the Fourier coefficients characterizing the cavity radius and the velocity potential as a function of downstream location and circumferential location, thus resulting in a two-dimensional multipole solution at each station. For the lowestorder term in the Fourier expansion, it is necessary to match the parabolic inner solution to a fully elliptic outer solution. This step allows the application of any one of a number of methods to solve the axisymmetric problem, which serves as the base solution that is perturbed by the three-dimensional effects. The method is an attempt to formalize the Logvinovich principle of independent cavity section evolution. Results flow past a circular disk cavitator are presented for severalvalues of the cavity Froude number.http://deepblue.lib.umich.edu/bitstream/2027.42/84318/1/CAV2009-final145.pd

Self help programs: A description of their characteristics and their members

User-run programs have proliferated in the past 10 years, yet there are few empirically-based studies about them. A survey of self-help programs was undertaken to increase our understanding about the users of such programs, their demographics, and their perceptions of how such programs have affected the quality of their lives. Respondents were also asked about their satisfaction with user-run programs. The study was conducted using a Participatory Action Research paradigm (Whyte, 1991), using an advisory committee of persons who have used such pro­grams, and with the intention of developing an evaluation methodology that could be replicated in future studies of user-run programs. Despite limitations in representativeness, these survey results are useful in understanding the perceptions of self-help members. Results of the survey and the methodology are discussed

Privacy Rights Versus FOIA Disclosure Policy: The Uses and Effects Double Standard in Access to Personally-Identifiable Information in Government Records

The U.S. government maintains a vast amount of personally-identifiable information on millions of American citizens. Much of this information is contained in electronic databases maintained by federal agencies. Various Freedom of Information Act (FOIA) requesters, such as journalists, marketers, and union organizers seek this information for different purposes including investigative reporting and targeted solicitations. These kinds of uses are known as derivative uses because this government-compiled information is requested for purposes other than the official purposes for which the information was originally gathered. These and other derivative uses of personally-identifiable information often implicate privacy concerns. Conversely, restrictions on public access to federal agency records can pose negative public policy implications. This article explores the continuing conflict between protecting personal privacy rights and safeguarding public access rights to personally-identifiable information under FOIA

Methionine Adenosyltransferase I/III Deficiency in Portugal: High Frequency of a Dominantly Inherited Form in a Small Area of Douro High Lands

Methionine adenosyltransferase deficienc(MAT I/III deficiency) is an inborn error of metabolism resulting in isolated hypermethioninemia, and usually inherited as an autosomal recessive trait, although a dominant form has been reported in several families. During the last 6 years, approximately 520,000 newborns were screened in the Portuguese Newborn Screening Laboratory by MS/MS, and 21 cases of persistent hypermethioninemia were found. One case was confirmed to be a deficiency of cystathionine b-synthase and 20 cases were confirmed by MAT1A gene analysis to have an elevation of methionine due to MAT I/III deficiency, which indicates an incidence for this condition of 1/26,000. Twelve of the MAT I/III deficient newborns, belonging to 11 families, were identified in the northern region of Portugal and sent to the same treatment center, where they are under follow-up. Clinical, biochemical, and genetic characteristics of individuals from these 11 families are presented. Plasma methionine and homocysteine concentrations were found to be moderately increased in all newborns, and molecular analysis revealed that they all were heterozygous for R264H mutation. Normal growth,development, and neurological examination were observed in all cases, and cerebral MRI performed in six cases revealed myelination abnormalities in one case. Plasma methionine concentration for all 12 cases was always below 300 mM, and they are all on a normal diet for their age

An Experiment on Innovation and Collusion

This paper examines the relationship between product innovation and the success of price collusion using novel laboratory experiments. Average market prices in low innovation (LO) experiments are significantly higher than those in high innovation, but otherwise identical experiments. This price difference is attributed to LO experimental subjects\u27 greater common market experience. The data illustrate how collusion can be perceived as the only way to make it in LO markets where product innovation is not a viable strategy for increasing profits. They suggest that product homogeneity can be a proximate cause, and product innovation an ultimate cause, of collusion