Child support enforcement for teenage fathers: Problems and prospects

The NLSY data indicate that about 7.3 percent of teenage males become fathers and that very few of these fathers live with their children. Father absence and the concurrent increase in female-headed households are closely associated with the impoverishment of children. Most absent teen fathers never come into contact with the child support enforcement program, and the extent to which they financially support their children informally is not well understood. While the income of absent teen fathers is low in the teen years, it increases over time, as does the potential for collecting child support. Nevertheless, men who were absent teen fathers earn less in early adulthood than men who deferred parenting until age twenty or later and teen fathers who lived with their children. Early establishment of paternity and greater standardization in the treatment of adolescent fathers by the child support enforcement program are recommended. Further, the substantial and persistent income deficit experienced by adolescent fathers who live apart from their children raises an interesting dilemma. While children may benefit financially and psychosocially from living with two parents, the lower income of men who were absent teenage fathers may make them poor marital prospects. This raises doubts about the recent recommendations of some scholars that we should bring back the shotgun wedding.

Aperture synthesis for microwave radiometers in space

A technique is described for obtaining passive microwave measurements from space with high spatial resolution for remote sensing applications. The technique involves measuring the product of the signal from pairs of antennas at many different antenna spacings, thereby mapping the correlation function of antenna voltage. The intensity of radiation at the source can be obtained from the Fourier transform of this correlation function. Theory is presented to show how the technique can be applied to large extended sources such as the Earth when observed from space. Details are presented for a system with uniformly spaced measurements

Bridging the gap between social tagging and semantic annotation: E.D. the Entity Describer

Semantic annotation enables the development of efficient computational methods for analyzing and interacting with information, thus maximizing its value. With the already substantial and constantly expanding data generation capacity of the life sciences as well as the concomitant increase in the knowledge distributed in scientific articles, new ways to produce semantic annotations of this information are crucial. While automated techniques certainly facilitate the process, manual annotation remains the gold standard in most domains. In this manuscript, we describe a prototype mass-collaborative semantic annotation system that, by distributing the annotation workload across the broad community of biomedical researchers, may help to produce the volume of meaningful annotations needed by modern biomedical science. We present E.D., the Entity Describer, a mashup of the Connotea social tagging system, an index of semantic web-accessible controlled vocabularies, and a new public RDF database for storing social semantic annotations

Influences on the fraction of hydrophobic and hydrophilic black carbon in the atmosphere

Black carbon (BC) is a short term climate forcer that directly warms the atmosphere, slows convection, and hinders quantification of the effect of greenhouse gases on climate change. The atmospheric lifetime of BC particles with respect to nucleation scavenging in clouds is controlled by their ability to serve as cloud condensation nuclei (CCN). To serve as CCN under typical conditions, hydrophobic BC particles must acquire hygroscopic coatings. However, the quantitative relationship between coatings and hygroscopic properties for ambient BC particles is not known nor is the time scale for hydrophobic-to-hydrophilic conversion. Here we introduce a method for measuring the hygroscopicity of externally and internally mixed BC particles by coupling a single particle soot photometer with a humidified tandem differential mobility analyzer. We test this technique using uncoated and coated laboratory generated model BC compounds and apply it to characterize the hygroscopicity distribution of ambient BC particles. From these data we derive that the observed number fraction of BC that is CCN active at 0.2% supersaturation is generally low in an urban area near sources and that it varies with the trajectory of the airmass. We anticipate that our method can be combined with measures of air parcel physical and photochemical age to provide the first quantitative estimates for characterizing hydrophobic-to-hydrophilic conversion rates in the atmosphere.Peer reviewe

As-built design specifications of the LANDSAT Imagery Verification and Extraction System (LIVES). Volume 1: Test and appendices

There are no author-identified significant results in this report

Leptonic contribution to the bulk viscosity of nuclear matter

For beta-equilibrated nuclear matter we estimate the contribution to the bulk viscosity from purely leptonic processes, namely the conversion of electrons to and from muons. For oscillation frequencies in the kiloHertz range, we find that this process provides the dominant contribution to the bulk viscosity when the temperature is well below the critical temperature for superconductivity or superfluidity of the nuclear matter.Comment: 15 pages, LaTeX, new appendix and general clarifications in response to referee comment

Spatial Structure of Ion Beams in an Expanding Plasma

We report spatially resolved perpendicular and parallel, to the magnetic field, ion velocity distribution function (IVDF) measurements in an expanding argon helicon plasma. The parallel IVDFs, obtained through laser induced fluorescence (LIF), show an ion beam with v ≈ 8000 m/s flowing downstream and confined to the center of the discharge. The ion beam is measurable for tens of centimeters along the expansion axis before the LIF signal fades, likely a result of metastable quenching of the beam ions. The parallel ion beam velocity slows in agreement with expectations for the measured parallel electric field. The perpendicular IVDFs show an ion population with a radially outward flow that increases with distance from the plasma axis. Structures aligned to the expanding magnetic field appear in the DC electric field, the electron temperature, and the plasma density in the plasma plume. These measurements demonstrate that at least two-dimensional and perhaps fully three-dimensional models are needed to accurately describe the spontaneous acceleration of ion beams in expanding plasmas

Reconnaissance Study of Pleistocene Lake and Fluvial Deposits In and Near Ancestral Yellowstone Lake, Wyoming

Seven sequences of Pleistocene strata, five of them predominantly lacustrine, are described from outcrops north of Yellowstone Lake. These are (1) Turbid Lake sequence, 30–50 feet of white pumiceous claystone and tuff with carbonaceous partings and a distinctive compositional pattern of excesses and deficiencies of many elements; (2) Yellowstone Falls sequence, 75 feet or more of varved white claystone and tuff containing pollen and diatoms, overlain by gray conglomerate and sandstone; (3) Hayden Valley sequence, 200 feet or more of gray and white silt and claystone containing sparse diatoms; (4) Alum Creek sequence, 30 feet or more of bedded sand and gravel with lesser amounts of clay; (5) Mudkettle sequence, 150 feet or more of light gray to white, soft clay and claystone with lesser amounts of sandstone and conglomerate, moderately lithified in part, and containing some pollen and diatoms; (6) Astringent Creek Sand (newly named), a gray, commonly unlithified sand as much as 300 feet thick and containing abundant volcanic debris; and (7) Pelican Valley sequence, 120 feet or more of light gray to white, soft clay, silt, sand, and some pumice pebble conglomerate and shard beds; finer grained beds contain diatoms, pollen, and carbonaceous debris that has a radiocarbon date of 7,550 ±350 years. Other localized deposits with radiocarbon dates and abundant diatoms consist of white carbonaceous tuffaceous clay and sand with an age of 9,440±300 years, in Gibbon Canyon, and a gray and white carbonaceous clay, silt, and sand with an age of 3,750+300 years at Bannock Ford in Yellowstone Canyon. Slight arching of the Upper Basin Member of the Plateau Rhyolite caused the Yellowstone River to develop an antecedent course across it. Uplift of the Pelican Valley area during the last 7,500 years averaged about one foot in 50 years

Reconnaissance Study of Pleistocene Lake and Fluvial Deposits In and Near Ancestral Yellowstone Lake, Wyoming

Seven sequences of Pleistocene strata, five of them predominantly lacustrine, are described from outcrops north of Yellowstone Lake. These are (1) Turbid Lake sequence, 30–50 feet of white pumiceous claystone and tuff with carbonaceous partings and a distinctive compositional pattern of excesses and deficiencies of many elements; (2) Yellowstone Falls sequence, 75 feet or more of varved white claystone and tuff containing pollen and diatoms, overlain by gray conglomerate and sandstone; (3) Hayden Valley sequence, 200 feet or more of gray and white silt and claystone containing sparse diatoms; (4) Alum Creek sequence, 30 feet or more of bedded sand and gravel with lesser amounts of clay; (5) Mudkettle sequence, 150 feet or more of light gray to white, soft clay and claystone with lesser amounts of sandstone and conglomerate, moderately lithified in part, and containing some pollen and diatoms; (6) Astringent Creek Sand (newly named), a gray, commonly unlithified sand as much as 300 feet thick and containing abundant volcanic debris; and (7) Pelican Valley sequence, 120 feet or more of light gray to white, soft clay, silt, sand, and some pumice pebble conglomerate and shard beds; finer grained beds contain diatoms, pollen, and carbonaceous debris that has a radiocarbon date of 7,550 ±350 years. Other localized deposits with radiocarbon dates and abundant diatoms consist of white carbonaceous tuffaceous clay and sand with an age of 9,440±300 years, in Gibbon Canyon, and a gray and white carbonaceous clay, silt, and sand with an age of 3,750+300 years at Bannock Ford in Yellowstone Canyon. Slight arching of the Upper Basin Member of the Plateau Rhyolite caused the Yellowstone River to develop an antecedent course across it. Uplift of the Pelican Valley area during the last 7,500 years averaged about one foot in 50 years